Role of plant growth regulators and a saprobic fungus in enhancement of metal phytoextraction potential and stress alleviation in pearl millet.

Science.gov (United States)

Firdaus-e-Bareen; Shafiq, Muhammad; Jamil, Sidra

2012-10-30

"Assisted phytoextraction" involving application of chemical additives such as plant growth regulators (PGRs) has become a trend in phytoremediation technology. This study identifies a cost-effective, naturally available crude PGR (PGR1) that produces the same effects as the commercial PGR (PGR2), increasing metal uptake by plants and the reduction of metal stress. Assisted phytoextraction by pearl millet (Pennisetum glaucum) from a multi-metal (Cd, Cr, Cu, Fe, Na and Zn) contaminated soil medium with tannery solid waste (TSW) soil amendments of 5 and 10%, was evaluated in a full-factorial pot trial with PGR1, PGR2 and Trichoderma pseudokoningii as factors. The effects of these phytoextraction assistants were measured through dry biomass production, heavy metal uptake, stress tolerance enzymes catalase (CAT) and superoxide dismutase (SOD), soluble protein content of plant, and phytoextraction efficiency. Dry biomass and multi-metal accumulation were the highest in the soil treatments with a combined application of PGR1, PGR2 and T. pseudokoningii and the lowest in the control. The soluble protein contents and the SOD and CAT values were the highest in the 10% TSW treatment provided with PGR2+T. pseudokoningii, while the lowest were in the control. Thus, application of crude PGR in combination with other phytoextraction assistants can increase biomass production as well as multi-metal accumulation in plants. However, the biochemical properties of the plant depend on the level of TSW stress in the soil treatment as well as the type of phytoextraction assistants. Copyright © 2012 Elsevier B.V. All rights reserved.

Ethylenediamine disuccinic acid enhanced phytoextraction of nickel from contaminated soils using Coronopus didymus (L.) Sm.

Science.gov (United States)

Sidhu, Gagan Preet Singh; Bali, Aditi Shreeya; Singh, Harminder Pal; Batish, Daizy R; Kohli, Ravinder Kumar

2018-04-18

In a screenhouse, the applicability of biodegradable chelant ethylenediamine disuccinic acid (EDDS) to enhance Ni-phytoextraction by Coronopus didymus was tested for the first time. This study assayed the hypothesis based upon the role of EDDS on physiological and biochemical alterations and ameliorating phytoextraction capacity of C. didymus under nickel (Ni) stress. Pot experiments were conducted for 6 weeks and C. didymus plants were cultivated in soil artificially contaminated with 30, 50, and 70 mg kg -1 Ni treatments. Soil was amended with EDDS (2 mmol kg -1 ). Plants were harvested, 1 week after EDDS application. At 70 mg kg -1 Ni level, EDDS application dramatically enhanced the root and shoot Ni concentration from 665 and 644 to 1339 and 1338 mg kg -1 , respectively. Combination of Ni + EDDS induced alterations in biochemical parameters of plants. EDDS addition posed pessimistic effects on growth, biomass, photosynthetic activity and protein content of the plants. Besides, application of EDDS stimulated the generation of superoxide anion, H 2 O 2 content and MDA level. However, EDDS assisted mount in antioxidant activities (superoxide dismutase, catalase and glutathione peroxidase) considerably neutralised the toxicity induced by reactive oxygen species in plant tissues. The results revealed EDDS efficacy to ameliorate the performance of antioxidant enzymes and improved Ni translocation in plant tissues, thus strongly marked its affinity to be used together with C. didymus for Ni-phytoextraction. Copyright © 2018 Elsevier Ltd. All rights reserved.

STUDY ON PHYTOEXTRACTION BALANCE OF ZN, CD, PB FROM MINE-WASTE POLLUTED SOILS BY USING MEDICAGO SATIVA AND TRIFOLIUM PRATENSE SPECIES

Directory of Open Access Journals (Sweden)

B. LIXANDRU

2009-05-01

Full Text Available For a term of two years was studied phytoextractive potential of Zn, Cd and Pb using successive culture of alfalfa (Medicago sativa and red clover (Trifolium pratense. In the experimental plot was incorporated a quantity of 20 kg mine waste per square meter, providing in soil 1209 mg Zn/kg d.s., 4.70 mg Cd/kg d.s. and 188.2 mg Pb/kg d.s. The metals content accumulated in plants was determined at the two moments of biomass harvesting, and through balance calculations we could establish the phytoextraction efficiency of the two forage-grasses species. The obtained results indicate that both perennial forage-legumes species have a good phytoextractive capacity and tolerance for Zn and Pb, especially Trifolium pratense specie. By using this species as phytoextractors on soil polluted with 3.76 times more Pb and 4.03 times more Zn, is provided the reduction of metallic ions concentration in soil to limits admitted by laws in a period of 3, respectively, 4 years.

Feasibility of labile Zn phytoextraction using enhanced tobacco and sunflower: results of five- and one-year field-scale experiments in Switzerland.

Science.gov (United States)

Herzig, Rolf; Nehnevajova, Erika; Pfistner, Charlotte; Schwitzguebel, Jean-Paul; Ricci, Arturo; Keller, Charles

2014-01-01

Phytoextraction with somaclonal variants of tobacco and sunflower mutant lines (non-GMs) with enhanced metal uptake and tolerance can be a sustainable alternative to conventional destructive decontamination methods, especially for stripping bioavailable zinc excess in topsoil. The overall results of a 5-year time series experiment at field scale in north-eastern Switzerland confirm that the labile Zn pool in soil can be lowered by 45-70%, whereas subplots without phytoextraction treatment maintained labile Zn concentrations. In 2011, the phytoextraction experiment site was enlarged by a factor of 3, and the labile 0.1 M NaNO3 extractable Zn concentration in the soil was reduced up to 58% one period after harvest. A Mass Balance Analysis confirmed soil Zn decontamination in line with plant Zn uptake. The plants partially take Zn from the non-labile pool of the totaL The sustainability of Zn phytoextraction in subplots that no longer exceed the Swiss trigger value is now assessed over time. In contrary to the phytoextraction of total soil Zn which needs a long cleaning up time, the bioavailable Zn stripping is feasible within a few years period.

Feasibility of Using Phytoextraction to Remediate a Compost-Based Soil Contaminated with Cadmium.

Science.gov (United States)

Parisien, Michele A; Rutter, Allison; Zeeb, Barbara A

2015-01-01

Greenhouse and in-situ field experiments were used to determine the potential for phytoextraction to remediate soil contaminated with Cd from municipal solid waste (MSW) and sewage sludge (SS) compost application at a Peterborough (Canada) site. For the greenhouse experiment, one native (Chenopodium album) and three naturalized (Poa compressa, Brassica juncea, Helianthus annuus) plant species were planted in soil containing no detectable Cd (phytoextraction is therefore not feasible at this site. Though low Cd bioavailability has negative implications for Cd phytoextraction from MSW/SS compost-based soils, it may limit receptor exposure to Cd sufficiently to eliminate the potential for risk at this site.

Non-enhanced phytoextraction of cadmium, zinc, and lead by high-yielding crops.

Science.gov (United States)

Mayerová, Markéta; Petrová, Šárka; Madaras, Mikuláš; Lipavský, Jan; Šimon, Tomáš; Vaněk, Tomáš

2017-06-01

Heavy metal soil contamination from mining and smelting has been reported in several regions around the world, and phytoextraction, using plants to accumulate risk elements in aboveground harvestable organs, is a useful method of substantially reducing this contamination. In our 3-year experiment, we tested the hypothesis that phytoextraction can be successful in local soil conditions without external fertilizer input. The phytoextraction efficiency of 15 high-yielding crop species was assessed in a field experiment performed at the Litavka River alluvium in the Příbram region of Czechia. This area is heavily polluted by Cd, Zn, and Pb from smelter installations which also polluted the river water and flood sediments. Heavy metal concentrations were analyzed in the herbaceous plants' aboveground and belowground biomass and in woody plants' leaves and branches. The highest Cd and Zn mean concentrations in the aboveground biomass were recorded in Salix x fragilis L. (10.14 and 343 mg kg -1 in twigs and 16.74 and 1188 mg kg -1 in leaves, respectively). The heavy metal content in woody plants was significantly higher in leaves than in twigs. In addition, Malva verticillata L. had the highest Cd, Pb, and Zn concentrations in herbaceous species (6.26, 12.44, and 207 mg kg -1 , respectively). The calculated heavy metal removal capacities in this study proved high phytoextraction efficiency in woody species; especially for Salix × fragilis L. In other tested plants, Sorghum bicolor L., Helianthus tuberosus L., Miscanthus sinensis Andersson, and Phalaris arundinacea L. species are also recommended for phytoextraction.

Screening of chelating ligands to enhance mercury accumulation from historically mercury-contaminated soils for phytoextraction.

Science.gov (United States)

Wang, Jianxu; Xia, Jicheng; Feng, Xinbin

2017-01-15

Screening of optimal chelating ligands which not only have high capacities to enhance plant uptake of mercury (Hg) from soil but also can decrease bioavailable Hg concentration in soil is necessary to establish a viable chemically-assisted phytoextraction. Therefore, Brassica juncea was exposed to historically Hg-contaminated soil (total Hg, 90 mg kg -1 ) to investigate the efficiency of seven chelating agents [ammonium thiosulphate, sodium thiosulphate, ammonium sulfate, ammonium chloride, sodium nitrate, ethylenediaminetetraacetic acid (EDTA), and sodium sulfite] at enhancing Hg phytoextraction; the leaching of bioavailable Hg caused by these chelating agents was also investigated. The Hg concentration in control (treated with double-distilled water) plant tissues was below 1 mg kg -1 . The remarkably higher Hg concentration was found in plants receiving ammonium thiosulphate and sodium sulfite treatments. The bioaccumulation factors and translocation factors of ammonium thiosulphate and sodium sulfite treatments were significantly higher than those of the other treatments. The more efficient uptake of Hg by plants upon treatment with ammonium thiosulphate and sodium sulfite compared to the other treatments might be explained by the formation of special Hg-thiosulphate complexes that could be preferentially taken up by the roots and transported in plant tissues. The application of sulfite significantly increased bioavailable Hg concentration in soil compared with that in initial soil and control soil, whereas ammonium thiosulphate significantly decreased bioavailable Hg concentration. The apparent decrease of bioavailable Hg in ammonium thiosulphate-treated soil compared with that in sodium sulfite-treated soil might be attributable to the unstable Hg-thiosulphate complexes formed between thiosulphate and Hg; they could react to produce less bioavailable Hg in the soil. The results of this study indicate that ammonium thiosulphate may be an optimal chelating

Enhancing phytoextraction: the effect of chemical soil manipulation on mobility, plant accumulation, and leaching of heavy metals.

Science.gov (United States)

Schmidt, Ulrich

2003-01-01

For heavy metal-contaminated agricultural land, low-cost, plant-based phytoextraction measures can be a key element for a new land management strategy. When agents are applied into the soil, the solubility of heavy metals and their subsequent accumulation by plants can be increased, and, therefore, phytoextraction enhanced. An overview is given of the state of the art of enhancing heavy metal solubility in soils, increasing the heavy metal accumulation of several high-biomass-yielding and metal-tolerant plants, and the effect of these measures on the risk of heavy metal leaching. Several organic as well as inorganic agents can effectively and specifically increase solubility and, therefore, accumulation of heavy metals by several plant species. Crops like willow (Salix viminalis L.), Indian mustard [Brassica juncea (L.) Czern.], corn (Zea mays L.), and sunflower (Helianthus annuus L.) show high tolerance to heavy metals and are, therefore, to a certain extent able to use the surpluses that originate from soil manipulation. More than 100-fold increases of lead concentrations in the biomass of crops were reported, when ethylenediaminetetraacetic acid (EDTA) was applied to contaminated soils. Uranium concentrations could be strongly increased when citric acid was applied. Cadmium and zinc concentrations could be enhanced by inorganic agents like elemental sulfur or ammonium sulfate. However, leaching of heavy metals due to increased mobility in soils cannot be excluded. Thus, implementation on the field scale must consider measures to minimize leaching. So, the application of more than 1 g EDTA kg(-1) becomes inefficient as lead concentration in crops is not enhanced and leaching rate increases. Moreover, for large-scale applications, agricultural measures as placement of agents, dosage splitting, the kind and amount of agents applied, and the soil properties are important factors governing plant growth, heavy metal concentrations, and leaching rates. Effective

Molasses melanoidin-like products enhance phytoextraction of lead through three Brassica species.

Science.gov (United States)

Hatano, Ken-Ichi; Yamatsu, Takeshi

2018-05-12

Previously, it has been suggested that melanoidin-like products (MLP) from sugarcane molasses may accelerate copper phytoextraction. In this study, we evaluated the facilitatory effect of MLP on phytoextraction in a medium including cadmium or lead, the concentrations of which were adjusted around the regulation values of the Soil Contamination Countermeasures Act in Japan. Three Brassica species were tested based on their fast growth, high biomass productivity, and high heavy metal absorption. Both biomass and lead uptake in the nutrient medium with 1 mM lead nitrate were significantly increased by the addition of MLP, and almost all of the lead was accumulated in the root tissue. Therefore, MLP were able both to detoxify lead ions and to improve their bioavailability in Brassica species. In contrast, only these species with MLP or citric acid survived in the nutrient medium with 1 mM cadmium sulfate. The phytoextraction of cadmium using these species was therefore impractical under the Act.

Use of woods at continual phytoextraction

International Nuclear Information System (INIS)

Maruskova, A.

2007-01-01

Phytoextraction that used natural hyper-accumulators for cleaning polluted soil has more advantages than induced phytoextraction. After all, using the tree species as hypo-accumulators is very rarely. This paper notes about few characteristics of tree species, especially birch (Betula pendula), which should encourage the research and next, their using in the process of phytoextraction. (author)

The role of plant-associated bacteria in the mobilization and phytoextraction of trace elements in contaminated soils.

Science.gov (United States)

Sessitsch, Angela; Kuffner, Melanie; Kidd, Petra; Vangronsveld, Jaco; Wenzel, Walter W; Fallmann, Katharina; Puschenreiter, Markus

2013-05-01

Phytoextraction makes use of trace element-accumulating plants that concentrate the pollutants in their tissues. Pollutants can be then removed by harvesting plants. The success of phytoextraction depends on trace element availability to the roots and the ability of the plant to intercept, take up, and accumulate trace elements in shoots. Current phytoextraction practises either employ hyperaccumulators or fast-growing high biomass plants; the phytoextraction process may be enhanced by soil amendments that increase trace element availability in the soil. This review will focus on the role of plant-associated bacteria to enhance trace element availability in the rhizosphere. We report on the kind of bacteria typically found in association with trace element - tolerating or - accumulating plants and discuss how they can contribute to improve trace element uptake by plants and thus the efficiency and rate of phytoextraction. This enhanced trace element uptake can be attributed to a microbial modification of the absorptive properties of the roots such as increasing the root length and surface area and numbers of root hairs, or by increasing the plant availability of trace elements in the rhizosphere and the subsequent translocation to shoots via beneficial effects on plant growth, trace element complexation and alleviation of phytotoxicity. An analysis of data from literature shows that effects of bacterial inoculation on phytoextraction efficiency are currently inconsistent. Some key processes in plant-bacteria interactions and colonization by inoculated strains still need to be unravelled more in detail to allow full-scale application of bacteria assisted phytoremediation of trace element contaminated soils.

Enhanced phytoextraction: II. Effect of EDTA and citric acid on heavy metal uptake by Helianthus annuus from a calcareous soil.

Science.gov (United States)

Lesage, E; Meers, E; Vervaeke, P; Lamsal, S; Hopgood, M; Tack, F M G; Verloo, M G

2005-01-01

High biomass producing plant species, such as Helianthus annuus, have potential for removing large amounts of trace metals by harvesting the aboveground biomass if sufficient metal concentrations in their biomass can be achieved However, the low bioavailability of heavy metals in soils and the limited translocation of heavy metals to the shoots by most high biomass producing plant species limit the efficiency of the phytoextraction process. Amendment of a contaminated soil with ethylene diamine tetraacetic acid (EDTA) or citric acid increases soluble heavy metal concentrations, potentially rendering them more available for plant uptake. This article discusses the effects of EDTA and citric acid on the uptake of heavy metals and translocation to aboveground harvestable plant parts in Helianthus annuus. EDTA was included in the research for comparison purposes in our quest for less persistent alternatives, suitable for enhanced phytoextraction. Plants were grown in a calcareous soil moderately contaminated with Cu, Pb, Zn, and Cd and treated with increasing concentrations of EDTA (0.1, 1, 3, 5, 7, and 10 mmol kg(-1) soil) or citric acid (0.01, 0.05, 0.25, 0.442, and 0.5 mol kg(-1) soil). Heavy metal concentrations in harvested shoots increased with EDTA concentration but the actual amount of phytoextracted heavy metals decreased at high EDTA concentrations, due to severe growth depression. Helianthus annuus suffered heavy metal stress due to the significantly increased bioavailable metal fraction in the soil. The rapid mineralization of citric acid and the high buffering capacity of the soil made citric acid inefficient in increasing the phytoextracted amounts of heavy metals. Treatments that did not exceed the buffering capacity of the soil (heavy metal concentrations. Treatments with high concentrations resulted in a dissolution of the carbonates and compaction of the soil. These physicochemical changes caused growth depression of Helianthus annuus. EDTA and citric

Comparison of natural organic acids and synthetic chelates at enhancing phytoextraction of metals from a multi-metal contaminated soil

International Nuclear Information System (INIS)

Clistenes do Nascimento, Williams A.; Amarasiriwardena, Dula; Xing, Baoshan

2006-01-01

Chemically assisted phytoremediation has been developing to induce accumulation of metals by high biomass plants. Synthetic chelates have shown high effectiveness to reach such a goal, but they pose serious drawbacks in field application due to the excessive amount of metals solubilized. We compared the performance of synthetic chelates with naturally occurring low molecular weight organic acids (LMWOA) in enhancing phytoextraction of metals by Indian mustard (Brassica juncea) from multi-metal contaminated soils. Gallic and citric acids were able to induce removal of Cd, Zn, Cu, and Ni from soil without increasing the leaching risk. Net removal of these metals caused by LMWOA can be as much as synthetic chelates. A major reason for this is the lower phytotoxicity of LMWOA. Furthermore, supplying appropriate mineral nutrients increased biomass and metal removal. - Organic acids can be as efficient as synthetic chelates for use in phytoextraction of multi-metal contaminated soils

The use of a biodegradable chelator for enhanced phytoextraction of heavy metals by Festuca arundinacea from municipal solid waste compost and associated heavy metal leaching.

Science.gov (United States)

Zhao, Shulan; Jia, Lina; Duo, Lian

2013-02-01

In a column experiment with horizontal permeable barriers, the effects of a biodegradable chelator-nitrilotriacetic acid (NTA) on the uptake of heavy metals from municipal solid waste (MSW) compost by Festuca arundinacea and metal leaching were investigated. The use of NTA was effective in increasing Cu, Pb, and Zn uptakes in shoots of two crops of F. arundinacea. In columns with barriers and treated with 20 mmol NTA per kg MSW compost, metal uptakes by the first and second crop of F. arundinacea were, respectively, 3.8 and 4.0 times for Pb, and 1.8 and 1.7 times for Zn greater with the added NTA than without it. Though NTA application mobilized metals, it caused only slight leaching of metals from MSW compost. Permeable barriers positioned between compost and soil effectively reduced metal leaching. NTA-assisted phytoextraction by turfgrass with permeable barriers to cleanup heavy metal contaminated MSW compost should be environmentally safe. Copyright © 2012 Elsevier Ltd. All rights reserved.

Comparison of synthetic chelators and low molecular weight organic acids in enhancing phytoextraction of heavy metals by two ecotypes of Sedum alfredii Hance.

Science.gov (United States)

Liu, Dan; Islam, Ejazul; Li, Tingqiang; Yang, Xiaoe; Jin, Xiaofen; Mahmood, Qaisar

2008-05-01

Lab scale and pot experiments were conducted to compare the effects of synthetic chelators and low molecular weight organic acids (LMWOA) on the phytoextraction of multi-contaminated soils by two ecotypes of Sedum alfredii Hance. Through lab scale experiments, the treatment dosage of 5 and 10 mM for synthetic chelators and LMWOA, respectively, and the treatment time of 10 days were selected for pot experiment. In pot experiment, the hyperaccumulating ecotype (HE) was found more tolerant to the metal toxicity compared with the non-hyperaccumulating ecotype (NHE). EDTA for Pb, EDDS for Cu, and DTPA for Cu and Cd were found more effective to enhance heavy metal accumulation in the shoots of S. alfredii Hance. Compared with synthetic chelators, the phytoextraction ability of LMWOA was lesser. Considering the strong post-harvest effects of synthetic chelators, it is suggested that higher dosage of LMWOA could be practiced during phytoextraction, and some additional measures could also be taken to lower the potential environmental risks of synthetic chelators in the future studies.

The use of poplar during a two-year induced phytoextraction of metals from contaminated agricultural soils

Energy Technology Data Exchange (ETDEWEB)

Komarek, Michael [Department of Agrochemistry and Plant Nutrition, Czech University of Agriculture in Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic)], E-mail: komarek@af.czu.cz; Tlustos, Pavel [Department of Agrochemistry and Plant Nutrition, Czech University of Agriculture in Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic)], E-mail: tlustos@af.czu.cz; Szakova, Jirina [Department of Agrochemistry and Plant Nutrition, Czech University of Agriculture in Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic)], E-mail: szakova@af.czu.cz; Chrastny, Vladislav [Department of Applied Chemistry and Chemistry Teaching, University of South Bohemia, Studentska 13, 370 05, Ceske Budejovice (Czech Republic)], E-mail: vladislavchrastny@seznam.cz

2008-01-15

The efficiency of poplar (Populus nigra L. x Populus maximowiczii Henry.) was assessed during a two-year chemically enhanced phytoextraction of metals from contaminated soils. The tested metal mobilizing agents were EDTA (ethylenediaminetetraacetic acid) and NH{sub 4}Cl. EDTA was more efficient than chlorides in solubilizing metals (especially Pb) from the soil matrix. The application of chlorides only increased the solubility of Cd and Zn. However, the increased uptake of metals after the application of higher concentrations of mobilizing agents was associated with low biomass yields of the poplar plants and the extraction efficiencies after the two vegetation periods were thus comparable to the untreated plants. Additionally, the application of mobilizing agents led to phytotoxicity effects and increased mobility of metals. Higher phytoextraction efficiencies were observed for Cd and Zn compared to Pb and Cu. Poplars are therefore not suitable for chemically enhanced phytoextraction of metals from severely contaminated agricultural soils. - Application of mobilizing agents is not optimal during a two-year phytoextraction of metals from severely contaminated soils using poplars.

The use of poplar during a two-year induced phytoextraction of metals from contaminated agricultural soils

International Nuclear Information System (INIS)

Komarek, Michael; Tlustos, Pavel; Szakova, Jirina; Chrastny, Vladislav

2008-01-01

The efficiency of poplar (Populus nigra L. x Populus maximowiczii Henry.) was assessed during a two-year chemically enhanced phytoextraction of metals from contaminated soils. The tested metal mobilizing agents were EDTA (ethylenediaminetetraacetic acid) and NH 4 Cl. EDTA was more efficient than chlorides in solubilizing metals (especially Pb) from the soil matrix. The application of chlorides only increased the solubility of Cd and Zn. However, the increased uptake of metals after the application of higher concentrations of mobilizing agents was associated with low biomass yields of the poplar plants and the extraction efficiencies after the two vegetation periods were thus comparable to the untreated plants. Additionally, the application of mobilizing agents led to phytotoxicity effects and increased mobility of metals. Higher phytoextraction efficiencies were observed for Cd and Zn compared to Pb and Cu. Poplars are therefore not suitable for chemically enhanced phytoextraction of metals from severely contaminated agricultural soils. - Application of mobilizing agents is not optimal during a two-year phytoextraction of metals from severely contaminated soils using poplars

Phytoextraction of rhenium by lucerne (Medicago sativa) and erect milkvetch (Astragalus adsurgens) from alkaline soils amended with coal fly ash.

Science.gov (United States)

He, Honghua; Dong, Zhigang; Pang, Jiayin; Wu, Gao-Lin; Zheng, Jiyong; Zhang, Xingchang

2018-07-15

Coal fly ash (CFA) is an industrial waste generated in huge amounts worldwide, and the management of CFA has become an environmental concern. Recovery of valuable metals from CFA is one of the beneficial reuse options of CFA. Rhenium (Re) is one of the rarest metals in the Earth's crust and one of the most expensive metals of strategic significance in the world market. A CFA at the Jungar Thermal Power Plant, Inner Mongolia, China, contains more Re than two alkaline soils in the surrounding region. Pot experiments were undertaken to grow lucerne (Medicago sativa) and erect milkvetch (Astragalus adsurgens) in a loessial soil and an aeolian sandy soil amended with different rates (5%, 10%, 20%, and 40%) of CFA. The results show that plant growth was considerably enhanced and Re concentration in plants was significantly increased when CFA was applied to the alkaline soils at rates of ≤20%; while in some cases plant growth was also markedly enhanced by the 40% CFA treatment, which increased plant Re concentration the most of all treatments. Both lucerne and erect milkvetch showed potential for phytoextracting Re from CFA-amended alkaline soils. Using CFA for soil amendment not only offers a potential solution for the waste disposal problem of CFA, but the phytoextraction of Re by both lucerne and erect milkvetch may also bring an economic profit in the future. Copyright © 2018 Elsevier B.V. All rights reserved.

Phytoremediation of mixed-contaminated soil using the hyperaccumulator plant Alyssum lesbiacum: Evidence of histidine as a measure of phytoextractable nickel

International Nuclear Information System (INIS)

Singer, Andrew C.; Bell, Thomas; Heywood, Chloe A.; Smith, J.A.C.; Thompson, Ian P.

2007-01-01

In this study we examine the effects of polycyclic aromatic hydrocarbons (PAHs) on the ability of the hyperaccumulator plant Alyssum lesbiacum to phytoextract nickel from co-contaminated soil. Planted and unplanted mesocosms containing the contaminated soils were repeatedly amended with sorbitan trioleate, salicylic acid and histidine in various combinations to enhance the degradation of two PAHs (phenanthrene and chrysene) and increase nickel phytoextraction. Plant growth was negatively affected by PAHs; however, there was no significant effect on the phytoextraction of Ni per unit biomass of shoot. Exogenous histidine did not increase nickel phytoextraction, but the histidine-extractable fraction of soil nickel showed a high correlation with phytoextractable nickel. These results indicate that Alyssum lesbiacum might be effective in phytoextracting nickel from marginally PAH-contaminated soils. In addition, we provide evidence for the broader applicability of histidine for quantifying and predicting Ni phytoavailability in soils. - Alyssum lesbiacum was shown to phytoextract nickel from PAH-contaminated soils from which the pool of nickel accessed for phytoextraction is closely modelled by a histidine-soil extract

Phytoremediation of mixed-contaminated soil using the hyperaccumulator plant Alyssum lesbiacum: Evidence of histidine as a measure of phytoextractable nickel

Energy Technology Data Exchange (ETDEWEB)

Singer, Andrew C. [Centre for Ecology and Hydrology-Oxford, Mansfield Road, Oxford OX1 3SR (United Kingdom)]. E-mail: acsi@ceh.ac.uk; Bell, Thomas [Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS (United Kingdom); Heywood, Chloe A. [Centre for Ecology and Hydrology-Oxford, Mansfield Road, Oxford OX1 3SR (United Kingdom); Smith, J.A.C. [Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB (United Kingdom); Thompson, Ian P. [Centre for Ecology and Hydrology-Oxford, Mansfield Road, Oxford OX1 3SR (United Kingdom)

2007-05-15

In this study we examine the effects of polycyclic aromatic hydrocarbons (PAHs) on the ability of the hyperaccumulator plant Alyssum lesbiacum to phytoextract nickel from co-contaminated soil. Planted and unplanted mesocosms containing the contaminated soils were repeatedly amended with sorbitan trioleate, salicylic acid and histidine in various combinations to enhance the degradation of two PAHs (phenanthrene and chrysene) and increase nickel phytoextraction. Plant growth was negatively affected by PAHs; however, there was no significant effect on the phytoextraction of Ni per unit biomass of shoot. Exogenous histidine did not increase nickel phytoextraction, but the histidine-extractable fraction of soil nickel showed a high correlation with phytoextractable nickel. These results indicate that Alyssum lesbiacum might be effective in phytoextracting nickel from marginally PAH-contaminated soils. In addition, we provide evidence for the broader applicability of histidine for quantifying and predicting Ni phytoavailability in soils. - Alyssum lesbiacum was shown to phytoextract nickel from PAH-contaminated soils from which the pool of nickel accessed for phytoextraction is closely modelled by a histidine-soil extract.

Enhanced bioavailable contaminant stripping (EBCS): metal bioavailability for evaluation of phytoextraction success

OpenAIRE

Petruzzelli, Gianniantonio; Pedron, Francesca; Gorini, Francesca; Pezzarossa, Beatrice; Tassi, Eliana; Barbafieri, Meri

2013-01-01

Phytoextraction may be applied at field scale when the removal of bioavailable metals is the specific target of the technology. Residual metals in soil can be considered substantially inert or to be evaluated by site specific risk analysis.

The Effect of Pollination on Cd Phytoextraction From Soil by Maize (Zea mays L.).

Science.gov (United States)

Xu, Wending; Lu, Guining; Wang, Rui; Guo, Chuling; Liao, Changjun; Yi, Xiaoyun; Dang, Zhi

2015-01-01

A pot experiment was conducted to investigate the effects of pollination on cadmium (Cd) phytoextraction from soil by mature maize plants. The results showed that the unpollinated maize plants accumulated 50% more Cd than that of the pollinated plants, even though the dry weight of the former plants was 15% less than that of the latter plants. The Cd accumulation in root and leaf of the unpollinated maize plant was 0.47 and 0.89 times higher than that of the pollinated plant, respectively. The Cd concentration in the cob was significantly decreased because of pollination. Preventing pollination is a promising approach for enhancing the effectiveness of phytoextraction in Cd-contaminated soils by maize. This study suggested that in low Cd-contaminated soil pollination should be encouraged because accumulation of Cd in maize grains is very little and maize seeds can bring farmers economic benefits, while in high Cd-contaminated soil, inhibition of pollination can be applied to enhance phytoextraction of Cd from soil by maize plant.

Enhancement of metal(loid)s phytoextraction by Cannabis sativa L

Czech Academy of Sciences Publication Activity Database

Petrová, Šárka; Benešová, Dagmar; Soudek, Petr; Vaněk, Tomáš

2012-01-01

Roč. 10, č. 1 (2012), s. 631-641 ISSN 1459-0255 R&D Projects: GA MŠk 2B08058 Institutional research plan: CEZ:AV0Z50380511 Keywords : phytoextraction * chelate * glutathione * Cannabis sativa L. * metal Subject RIV: DK - Soil Contamination ; De-contamination incl. Pesticides Impact factor: 0.435, year: 2012 http://www.isfae.org/scientficjournal/2012/issue1/pdf/environment/e0.pdf

Enhanced Bioavailable Contaminant Stripping (EBCS: metal bioavailability for evaluation of phytoextraction success

Directory of Open Access Journals (Sweden)

Petruzzelli G.

2013-04-01

Full Text Available Phytoextraction may be applied at field scale when the removal of bioavailable metals is the specific target of the technology. Residual metals in soil can be considered substantially inert or to be evaluated by site specific risk analysis.

Enhanced phyto-extraction of cadmium and zinc using rapeseed

Energy Technology Data Exchange (ETDEWEB)

Ghani, M.; Slycken, S.V.; Meers, E.; Tack, F.M.G. [Laboratory of Analytical Chemistry and Applied Ecochemistry, Ghent University, Ghent (Belgium); Naz, F. [National Insect Museum, National Agricultural Research Centre, Islamabad (Pakistan); Ali, S. [Agriculture Department, University of Haripur, Haripur (Pakistan)

2013-07-01

In a green house pot experiment, the effects of three amendments, sulphur (S), ammonium sulphate ((NH{sub 4}){sub 2}SO{sub 4}) and ethylenediaminetetracetic acid (EDTA) were tested for phyto-extraction of Cd and Zn by rapeseed (Brassica napus L.). Elemental sulphur was applied as 20.00, 60.00, and 120.00 mg.kg{sup -1} soil. EDTA was tested at a dose of 585.00 mg.kg{sup -1} soil, and (NH{sub 4}){sub 2}SO{sub 4}) at a rate of 0.23 mg.kg{sup -1} soil. All treatments received a base fertilization (Hogland) before sowing. Plants were harvested after 51 days of growth and shoot dry matter and soil samples were analysed for metal contents. All amendments caused a significant increase in Cd and Zn contents in plant shoots of all treatments than control treatment. Further, EDTA was most effective for extraction metals concentrations in shoot biomass but the plants showed significant signs of toxicity and yield were severely depressed. The addition of sulfur favorably influenced plant biomass production. The fertilized ammonium sulfate treatment resulted in the highest phyto-extraction of Cd and Zn and the amounts of these metals accumulated in plant shoot exceeded by a factor of 4 and 3 respectively. Finally, Brassica napus could be used for soil remediation keeping its other uses which will make the contaminated site income generating source for the farmers. (authors)

Phytoextraction of potentially toxic elements by Indian mustard, rapeseed, and sunflower from a contaminated riparian soil.

Science.gov (United States)

Shaheen, Sabry M; Rinklebe, Jörg

2015-12-01

The objective of this study was to quantify the phytoextraction of the potentially toxic elements Al, As, Cd, Co, Cr, Cu, Mo, Ni, Pb, Se, V, and Zn by Indian mustard, rapeseed, and sunflower from a contaminated riparian soil. To achieve this goal, a greenhouse pot experiment was established using a highly contaminated grassland soil collected at the Wupper River (Germany). The impact of ethylene-diamine-tetra-acetic acid (EDTA), humate (HK), and phosphate potassium (PK) on the mobility and uptake of the elements by rapeseed also was investigated. Indian mustard showed the highest efficiency for phytoextraction of Al, Cr, Mo, Se, and V; sunflower for Cd, Ni, Pb, and Zn, and rapeseed for Cu. The bioconcentration ratios were higher than 1 for the elements (except As and Cu), indicating the suitability of the studied plants for phytoextraction. Application of EDTA to the soil increased significantly the solubility of Cd, Co, Cr, Ni, and Pb and decreased the solubility of Al, As, Se, V, and Mo. Humate potassium decreased significantly the concentrations of Al and As in rapeseed but increased the concentrations of Cu, Se, and Zn. We may conclude that HK can be used for immobilization of Al and As, while it can be used for enhancing the phytoextraction of Cu, Se, and Zn by rapeseed. Phosphate potassium immobilized Al, Cd, Pb, and Zn, but enhanced phytoextraction of As, Cr, Mo, and Se by rapeseed.

EDTA-induced phytoextraction of lead and barium by brachiaria (B. decumbens cv. Basilisk in soil contaminated by oil exploration drilling waste

Directory of Open Access Journals (Sweden)

André Fernão Martins de Andrade

2014-08-01

Full Text Available The phytoextraction of heavy metals using chelating agents has been widely studied for the remediation of contaminated soils. To evaluate the efficiency of EDTA-induced phytoextraction of Ba and Pb using Brachiaria decumbens for the remediation of soil contaminated by oil well drilling and exploration waste, an experiment was conducted by applying a single dose (6 mmol EDTA kg-1 soil and split doses of EDTA (three applications of 2 mmol EDTA kg-1 soil. The samples were subjected to sequential extractions using the method proposed by Ure et al. (1993 as modified by Rauret et al. (1999.The application of EDTA did not influence the distribution of Ba in various chemical fractions of the soil. The dry matter production did not differ significantly between the treatments and the control, thereby demonstrating the tolerance of plants to the experimental conditions. The absorption of Pb by plants was influenced by the application of EDTA. The application of a single dose of EDTA influenced the absorption of Pb and its translocation to the aerial plant parts. The application of split doses favoured higher accumulation of Pb in roots. Because of its tolerance to heavy metals and EDTA, B. decumbens has the potential to be used in phytostabilisation.

EDTA-assisted phytoextraction of heavy metals by turfgrass from municipal solid waste compost using permeable barriers and associated potential leaching risk.

Science.gov (United States)

Zhao, Shulan; Lian, Fei; Duo, Lian

2011-01-01

A column experiment with horizontal permeable barriers was conducted to investigate phytoextraction of heavy metals by Lolium perenne L. from municipal solid waste compost following EDTA application, as well as to study the effects of L. perenne and permeable barriers on preventing metal from leaching. In columns with barriers, EDTA addition yielded maximum concentrations of Cu, Zn and Pb of 155, 541 and 33.5 mg kg(-1) in shoot, respectively. This led to 4.2, 2.1 and 7.4 times higher concentrations of Cu, Zn and Pb compared to treatment with no chelating agent, respectively. In treatments with 10 mmol kg(-1) EDTA, the barriers reduced leaching of Cu, Zn and Pb by approximately three times, respectively, resulting in leaching of total initial Cu, Zn and Pb by 27.3%, 25.2% and 28.8%, respectively, after four times' irrigation. These results indicate that L. perenne and permeable barriers are effective to reduce leaching of heavy metals and minimize the risk of contaminating groundwater in EDTA-enhanced phytoremediation. Thus these findings highlight that turfgrass and permeable barriers can effectively prevent metal leaching. Copyright © 2010 Elsevier Ltd. All rights reserved.

Role of microbial inoculation and chitosan in phytoextraction of Cu, Zn, Pb and Cd by Elsholtzia splendens - a field case

Energy Technology Data Exchange (ETDEWEB)

Wang Fayuan [Agricultural College, Henan University of Science and Technology, 70 Tianjin Road, Luoyang, Henan Province 471003 (China) and Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu Province 210008 (China)]. E-mail: wfy1975@163.com; Lin Xiangui [Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu Province 210008 (China); Yin Rui [Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu Province 210008 (China)

2007-05-15

A field experiment was carried out to study the effect of microbial inoculation on heavy metal phytoextraction by Elsholtzia splendens and whether chitosan could have a synergistic effect with the microbial inocula. The microbial inocula consisted of a consortium of arbuscular mycorrhizal fungi and two Penicillium fungi. Three treatments were included: the control, inoculation with microbial inocula, and the inoculation combined with chitosan. Microbial inoculation increased plant biomass especially shoot dry weight, enhanced shoot Cu, Zn and Pb concentrations but did not affect Cd, leading to higher shoot Cu, Zn, Pb and Cd uptake. Compared with microbial inoculation alone, chitosan application did not affect plant growth but increased shoot Zn, Pb and Cd concentrations except Cu, which led to higher phytoextraction efficiencies and partitioning to shoots of Zn, Pb and Cd. These results indicated synergistic effects between microbial inocula and chitosan on Zn, Pb and Cd phytoextraction. - Co-application of microbial inocula and chitosan enhanced heavy metal phytoextraction by E. splendens.

Role of microbial inoculation and chitosan in phytoextraction of Cu, Zn, Pb and Cd by Elsholtzia splendens - a field case

International Nuclear Information System (INIS)

Wang Fayuan; Lin Xiangui; Yin Rui

2007-01-01

A field experiment was carried out to study the effect of microbial inoculation on heavy metal phytoextraction by Elsholtzia splendens and whether chitosan could have a synergistic effect with the microbial inocula. The microbial inocula consisted of a consortium of arbuscular mycorrhizal fungi and two Penicillium fungi. Three treatments were included: the control, inoculation with microbial inocula, and the inoculation combined with chitosan. Microbial inoculation increased plant biomass especially shoot dry weight, enhanced shoot Cu, Zn and Pb concentrations but did not affect Cd, leading to higher shoot Cu, Zn, Pb and Cd uptake. Compared with microbial inoculation alone, chitosan application did not affect plant growth but increased shoot Zn, Pb and Cd concentrations except Cu, which led to higher phytoextraction efficiencies and partitioning to shoots of Zn, Pb and Cd. These results indicated synergistic effects between microbial inocula and chitosan on Zn, Pb and Cd phytoextraction. - Co-application of microbial inocula and chitosan enhanced heavy metal phytoextraction by E. splendens

Phytoextraction of Cd-Contaminated Soils: Current Status and Future Challenges.

Science.gov (United States)

Li, Jin-Tian; Baker, Alan J M; Ye, Zhi-Hong; Wang, Hong-Bin; Shu, Wen-Sheng

2012-10-01

Cadmium (Cd) is one of the most toxic and widely distributed pollutants in the environment. Cadmium contamination of soils has posed a serious threat to safe food production in many parts of the world. The authors present a comprehensive review of present status of phytoextraction technology for cleaning up Cd-contaminated soils, based primarily on the data resulting from both laboratory and field-scale studies that have been conducted to assess or improve the Cd phytoextraction potential of various plant species in the past decade. The encouraging results of field-scale studies have provided a fundamental basis to usher phytoextraction technology into practical use to remediate slightly to moderately Cd-contaminated soils in Europe and Asia, although this technology is not yet ready for widespread application. Chelators and microorganisms tested so far seem not to contribute to the applicability of Cd phytoextraction. The major challenges for the large-scale application of Cd phytoextraction are (a) how to further improve the efficiency of Cd phytoextraction, (b) how to cut the overall costs of Cd phytoextraction, and (c) how to get greater stakeholders' acceptance of Cd phytoextraction as a reliable option.

Phytoextraction of mine wastes - Options and impossibilities. Chemie der Erde - Geochemie der Erde.

NARCIS (Netherlands)

Ernst, W.H.O.

2005-01-01

Phytoextraction is a green in situ technology which aims to diminish the concentration of the chemical element(s) (often synonymous with heavy metals) of contaminated soils to such a level that the soil can be used without danger for agriculture, horticulture, forestry or amenity. To a chieve this

Phytoextraction of heavy metals from contaminated soil by co-cropping with chelator application and assessment of associated leaching risk.

Science.gov (United States)

Wei, Z B; Guo, X F; Wu, Q T; Long, X X; Penn, C J

2011-08-01

Phytoextraction using hyperaccumulating plants is generally time-consuming and requires the cessation of agriculture. We coupled chelators and a co-cropping system to enhance phytoextraction rates, while allowing for agricultural production. An experiment on I m3 lysimeter beds was conducted with a co-cropping system consisting of the hyperaccumulator Sedum alfredii and low-accumulating corn (Zea Mays, cv. Huidan-4), with addition ofa mixture of chelators (MC), to assess the efficiency of chelator enhanced co-crop phytoextraction and the leaching risk caused by the chelator. The results showed that the addition of MC promoted the growth of S. alfredii in the first crop (spring-summer season) and significantly increased the metal phytoextraction. The DTPA-extractable and total metal concentrations in the topsoil were also reduced more significantly with the addition of MC compared with the control treatments. However, mono-cropped S. alfredii without MC was more suitable for maximizing S. alfredii growth and therefore phytoextraction of Zn and Cd during the autumn-winter seasons. No adverse impact to groundwater due to MC application was observed during the experiments with three crops and three MC applications. But elevated total Cd and Pb concentrations among subsoils compared to the initial subsoil concentrations were found for the co-crop + MC treatment after the third crop.

Determining soil enzyme activities for the assessment of fungi and citric acid-assisted phytoextraction under cadmium and lead contamination.

Science.gov (United States)

Mao, Liang; Tang, Dong; Feng, Haiwei; Gao, Yang; Zhou, Pei; Xu, Lurong; Wang, Lumei

2015-12-01

Microorganism or chelate-assisted phytoextraction is an effective remediation tool for heavy metal polluted soil, but investigations into its impact on soil microbial activity are rarely reported. Consequently, cadmium (Cd)- and lead (Pb)-resistant fungi and citric acid (CA) were introduced to enhance phytoextraction by Solanum nigrum L. under varied Cd and Pb pollution levels in a greenhouse pot experiment. We then determined accumulation of Cd and Pb in S. nigrum and the soil enzyme activities of dehydrogenase, phosphatase, urease, catalase, sucrase, and amylase. Detrended canonical correspondence analysis (DCCA) was applied to assess the interactions between remediation strategies and soil enzyme activities. Results indicated that the addition of fungi, CA, or their combination enhanced the root biomass of S. nigrum, especially at the high-pollution level. The combined treatment of CA and fungi enhanced accumulation of Cd about 22-47 % and of Pb about 13-105 % in S. nigrum compared with the phytoextraction alone. However, S. nigrum was not shown to be a hyperaccumulator for Pb. Most enzyme activities were enhanced after remediation. The DCCA ordination graph showed increasing enzyme activity improvement by remediation in the order of phosphatase, amylase, catalase, dehydrogenase, and urease. Responses of soil enzyme activities were similar for both the addition of fungi and that of CA. In summary, results suggest that fungi and CA-assisted phytoextraction is a promising approach to restoring heavy metal polluted soil.

Enhancement of Cd phytoextraction by hyperaccumulator Sedum alfredii using electrical field and organic amendments.

Science.gov (United States)

Xiao, Wendan; Li, Dan; Ye, Xuezhu; Xu, Haizhou; Yao, Guihua; Wang, Jingwen; Zhang, Qi; Hu, Jing; Gao, Na

2017-02-01

The combined use of organic amendment-assisted phytoextraction and electrokinetic remediation to decontaminate Cd-polluted soil was demonstrated in a laboratory-scale experiment. The plant species selected was the hyperaccumulator Sedum alfredii. Prior to the pot experiment, the loamy soil was treated with 15 g kg -1 of pig manure compost, 10 g kg -1 of humic acid, or 5 mmol kg -1 of EDTA, and untreated soil without application of any amendment was the control. Two conditions were applied to each treatment: no voltage (without an electrical field) and a direct current (DC) electrical field (1 V cm -1 with switching polarity every day). Results indicated that Cd concentrations in S. alfredii were significantly (p phytoextraction by hyperaccumulator S. alfredii.

EDDS and EDTA-enhanced phytoextraction of metals from artificially contaminated soil and residual effects of chelant compounds

Energy Technology Data Exchange (ETDEWEB)

Luo Chunling [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); Shen Zhenguo [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Lou Laiqing [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Li Xiangdong [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)]. E-mail: cexdli@polyu.edu.hk

2006-12-15

The potential of 18 different plants to be used in the chemically enhanced phytoextraction of Cu, Pb, Zn and Cd was assessed using pot experiments. Chrysanthemum coronarium L. was the species most sensitive to the application of EDTA, and had the highest enhancement of Cu and Pb concentrations in its shoots. Compared with EDTA, EDDS was more effective in enhancing the concentration of Cu in the shoots of Chrysanthemum coronarium L. and Zea mays L. grown on multi-metal contaminated soils. The EDTA-treated soil still had a significant ability to enhance the concentrations of Cu and Pb in the shoots of Zea mays L. six months after the chelant treatment. However, the EDDS-treated soil did not have any effect in enhancing the concentrations of metals in the shoots of Zea mays L. in the second crop test. The results may indicate that EDDS biodegrades more rapidly than EDTA in soil and is better in limiting potential metal leaching. - Chrysanthemum coronarium L. was the most sensitive species to the application of chelants, and EDDS biodegrades much more rapidly than EDTA in soil.

EDDS and EDTA-enhanced phytoextraction of metals from artificially contaminated soil and residual effects of chelant compounds

International Nuclear Information System (INIS)

Luo Chunling; Shen Zhenguo; Lou Laiqing; Li Xiangdong

2006-01-01

The potential of 18 different plants to be used in the chemically enhanced phytoextraction of Cu, Pb, Zn and Cd was assessed using pot experiments. Chrysanthemum coronarium L. was the species most sensitive to the application of EDTA, and had the highest enhancement of Cu and Pb concentrations in its shoots. Compared with EDTA, EDDS was more effective in enhancing the concentration of Cu in the shoots of Chrysanthemum coronarium L. and Zea mays L. grown on multi-metal contaminated soils. The EDTA-treated soil still had a significant ability to enhance the concentrations of Cu and Pb in the shoots of Zea mays L. six months after the chelant treatment. However, the EDDS-treated soil did not have any effect in enhancing the concentrations of metals in the shoots of Zea mays L. in the second crop test. The results may indicate that EDDS biodegrades more rapidly than EDTA in soil and is better in limiting potential metal leaching. - Chrysanthemum coronarium L. was the most sensitive species to the application of chelants, and EDDS biodegrades much more rapidly than EDTA in soil

Sulfur-aided phytoextraction of Cd and Zn by Salix smithiana combined with in situ metal immobilization by gravel sludge and red mud

International Nuclear Information System (INIS)

Iqbal, Muhammad; Puschenreiter, Markus; Oburger, Eva; Santner, Jakob; Wenzel, Walter W.

2012-01-01

As phytoextraction implementation may be limited by metal toxicity and leaching, we investigated the idea of in situ metal immobilization in bulk soil, while increasing metal bioavailability in the rhizosphere. Salix smithiana was grown in a pot experiment on two Cd/Zn polluted soils. Treatments with or without willows included: no additives; gravel sludge + red mud kg −1 ; acidification with S to pH 3.5; and metal immobilization combined with soil acidification. Salix smithiana removed up to 0.78 ± 0.06% total Cd and 0.34% (±0.02) total Zn from the non-treated soils. The phytoextraction efficiency in the S treatments was enhanced by up to ∼50% in response to metal solubility that was magnified by reductive co-dissolution from Mn (IV) and Fe(III) (oxy)hydroxides during microbial S oxidation in the willow rhizosphere. The proposed technique proved to enhance phytoextraction efficiency while controlling the risk of metal leaching from the root zone and phytotoxicity. - Highlights: ► Phytoextraction of Cd and Zn using willow (Salix smithiana) was enhanced by elemental sulfur. ► Reductive metals dissolution by microbial S oxidation was magnified in the willow rhizosphere. ► Thus metal bioavailability was high at the location of uptake in the phytoextraction crop. ► Concurrent immobilization by soil amendments can reduce metal leaching from the bulk soil. - Magnified Cd and Zn availability in S-amended rhizosphere of Salix smithiana enhances shoot Cd/Zn removal while metal leaching from the root zone can be reduced by immobilizing soil amendments.

Phytoextraction and assisted phytoextraction of metals from agriculture used soil

Czech Academy of Sciences Publication Activity Database

Trakal, L.; Neuberg, M.; Száková, J.; Vohník, Martin; Tejnecký, V.; Drábek, O.; Tlustoš, P.

2013-01-01

Roč. 44, č. 12 (2013), s. 1862-1872 ISSN 0010-3624 Grant - others:Norwegian Financial Mechanism(CZ) EEA Grants CZ0092 Institutional support: RVO:67985939 Keywords : phytoextraction * heavy metals * agriculture soil Subject RIV: EF - Botanics Impact factor: 0.423, year: 2013

Ethylenediaminedisuccinic acid (EDDS) enhances phytoextraction of lead by vetiver grass from contaminated residential soils in a panel study in the field.

Science.gov (United States)

Attinti, Ramesh; Barrett, Kirk R; Datta, Rupali; Sarkar, Dibyendu

2017-06-01

Phytoextraction is a green remediation technology for cleaning contaminated soils. Application of chelating agents increases metal solubility and enhances phytoextraction. Following a successful greenhouse experiment, a panel study under field weather elucidated the efficiency of the chelating agent ethylenediaminedisuccinic acid (EDDS) on phytoextraction of lead (Pb) by vetiver grass, a hyperaccumulator of Pb, and a nonaccumulator fescue grass from residential soils contaminated with Pb-based paint from Baltimore, MD and San Antonio, TX. Three soils from each city with Pb content between 1000 and 2400 mg kg -1 were chosen for the panel study. Sequential extraction revealed that Fe-Mn oxide (60-63%) and carbonate (25-33%) fractions of Pb dominated in Baltimore soils, whereas in San Antonio soils, Pb was primarily bound to the organic fraction (64-70%) because organic content was greater and, secondarily, to the Fe-Mn oxide (15-20%) fraction. Vetiver and fescue grasses were transplanted and grown on wood panels in the field with EDDS applied after 3 months and 13 months. Soil and leachate results indicated that EDDS applications increased Pb solubility in soils. Plant tissues results indicated enhanced the uptake of Pb by vetiver and showed that EDDS application promoted translocation of Pb from root to shoot. Average Pb concentration increased by 53% and 203% in shoots and by 73% and 84% in roots of vetiver after the first and second applications of EDDS, respectively. Concentrations in roots and shoots increased in all tested soils, regardless of soil pH or clay content. After the second application, average Pb concentrations in vetiver were higher than those in fescue by 3.6x in shoots and 8.3x in roots. Visual phytotoxic symptoms from increased bioavailable Pb from EDSS applications were observed in fescue but not in vetiver. This study demonstrated the potential of a chemically-catalyzed phytoremediation system as a cleanup method for lead-contaminated soils

Heating treatment schemes for enhancing chelant-assisted phytoextraction of heavy metals from contaminated soils.

Science.gov (United States)

Chen, Yahua; Wang, Chunchun; Wang, Guiping; Luo, Chunling; Mao, Ying; Shen, Zhenguo; Li, Xiangdong

2008-04-01

Recent research has shown that chelant-assisted phytoextraction approaches often require a high dosage of chelant applied to soil. The present study focused on optimization of phytoremediation processes to increase the phytoextraction efficiency of metals at reduced chelant applications. Pot experiments were carried out to investigate the effects of increased soil temperature on shoot uptake of heavy metals by corn (Zea mays L.) and mung bean (Vigna radiat L. Wilczek) from heavy metal-contaminated soils. After the application of S,S-ethylenediaminedisuccinic acid or ethylenediaminetetra-acetic acid, soils were exposed to high temperatures (50 or 80 degrees C) for 3 h, which significantly increased the concentration of heavy metals in shoots. The heating treatment 2 d after the chelant addition resulted in higher concentrations of metals compared with those treatments 2 d before or simultaneously with the chelant application. Irrigation with 100 degrees C water 2 d after the chelant addition, or irrigation with 100 degrees C chelant solutions directly, also resulted in significantly higher phytoextraction of metals in the two crops compared with 25 degrees C chelant solutions. In addition, a novel application method to increase soil temperature using underground polyvinyl chloride tubes would increase the chelant-assisted extraction efficiency of Cu approximately 10- to 14-fold in corn and fivefold in mung bean compared with those nonheating treatments. In a field experiment, increasing soil temperature 2 d after chelant addition also increased the shoot Cu uptake approximately fivefold compared with those nonheating treatments. This new technique may represent a potential, engineering-oriented approach for phytoremediation of metal-polluted soils.

Phytoextraction of contaminated urban soils by Panicum virgatum L. enhanced with application of a plant growth regulator (BAP) and citric acid.

Science.gov (United States)

Aderholt, Matthew; Vogelien, Dale L; Koether, Marina; Greipsson, Sigurdur

2017-05-01

Lead (Pb) contamination in soil represents a threat to human health. Phytoextraction has gained attention as a potential alternative to traditional remediation methods because of lower cost and minimal soil disruption. The North American native switchgrass (Panicum virgatum L.) was targeted due to its ability to produce high biomass and grow across a variety of ecozones. In this study switchgrass was chemically enhanced with applications of the soil-fungicide benomyl, chelates (EDTA and citric acid), and PGR to optimize phytoextraction of Pb and zinc (Zn) from contaminated urban soils in Atlanta, GA. Exogenous application of two plant hormones was compared in multiple concentrations to determine effects on switchgrass growth: indole-3-acetic acid (IAA), and Gibberellic Acid (GA 3 ), and one PGR benzylaminopurine (BAP), The PGR BAP (1.0 μM) was found to generate a 48% increase in biomass compared to Control plants. Chemical application of citric acid, EDTA, benomyl, and BAP were tested separately and in combination in a pot experiment in an environmentally controlled greenhouse to determine the efficacy of phtyoextraction by switchgrass. Soil acidification by citric acid application resulted in highest level of aluminum (Al) and iron (Fe) in plants foliage resulting in severe phytotoxic effects. Total Pb phytoextraction was significantly highest in plants treated with combined chemical application of B + C and B + C + H. Suppression of AMF activities by benomyl application significantly increased concentrations of Al and Fe in roots. Application of benomyl reduced AMF colonization but was also shown to dramatically increase levels of septa fungi infection as compared to Control plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Non-enhanced phytoextraction of cadmium, zinc, and lead by high-yielding crops

Czech Academy of Sciences Publication Activity Database

Mayerová, M.; Petrová, Šárka; Madaras, M.; Lipavský, J.; Šimon, T.; Vaněk, Tomáš

2017-01-01

Roč. 24, č. 17 (2017), s. 14706-14716 ISSN 0944-1344 R&D Projects: GA MŠk 2B08058; GA MŠk(CZ) LD14106; GA MŠk(CZ) LD14107 Institutional support: RVO:61389030 Keywords : Field trial * Heavy metals * Minimum inputs * Phytoextraction * Soil contamination Subject RIV: DK - Soil Contamination ; De-contamination incl. Pesticides OBOR OECD: Bioremediation, diagnostic biotechnologies (DNA chips and biosensing devices) in environmental management Impact factor: 2.741, year: 2016

Chelate-assisted phytoextraction: effect of EDTA and EDDS on copper uptake by Brassica napus L.

Directory of Open Access Journals (Sweden)

TIJANA M. ZEREMSKI-ŠKORIĆ

2010-09-01

Full Text Available Chelate-assisted phytoextraction is proposed as an effective approach for the removal of heavy metals from contaminated soil through the use of high biomass plants. The aim of the present study was to compare the efficiency of the two chelators: EDTA and biodegradable EDDS in enhancing Cu uptake and translocation by Brassica napus L. grown on moderately contaminated soil and treated with increasing concentrations of EDTA or EDDS. Increasing amounts of EDDS caused serious growth suppression of B. napus and an increase in shoot metal concentrations. Growth suppression limited the actual amount of phytoextracted Cu at high concentrations of EDDS. The maximum amount of extracted Cu was achieved by the application of 8.0 and 4.0+4.0 mmol kg-1 EDDS. The shoot Cu concentrations after EDTA application were much lower than with EDDS at the same doses. According to these experiments, EDTA does not appear to be an efficient amendment if Cu phytoextraction with B. napus is considered but EDDS is.

Assessment of the phytoextraction potential of high biomass crop plants

Energy Technology Data Exchange (ETDEWEB)

Hernandez-Allica, Javier [NEIKER-tecnalia, Basque Institute of Agricultural Research and Development, c/Berreaga 1, E-48160 Derio (Spain); Becerril, Jose M. [Department of Plant Biology and Ecology, University of the Basque Country, P.O. Box 644, E-48080 Bilbao (Spain); Garbisu, Carlos [NEIKER-tecnalia, Basque Institute of Agricultural Research and Development, c/Berreaga 1, E-48160 Derio (Spain)], E-mail: cgarbisu@neiker.net

2008-03-15

A hydroponic screening method was used to identify high biomass crop plants with the ability to accumulate metals. Highest values of shoot accumulation were found in maize cv. Ranchero, rapeseed cv. Karat, and cardoon cv. Peralta for Pb (18 753 mg kg{sup -1}), Zn (10 916 mg kg{sup -1}), and Cd (242 mg kg{sup -1}), respectively. Subsequently, we tested the potential of these three cultivars for the phytoextraction of a metal spiked compost, finding out that, in cardoon and maize plants, increasing Zn and Cd concentrations led to lower values of root and shoot DW. By contrast, rapeseed shoot growth was not significantly affected by Cd concentration. Finally, a metal polluted soil was used to check these cultivars' phytoextraction capacity. Although the soil was phytotoxic enough to prevent the growth of cardoon and rapeseed plants, maize plants phytoextracted 3.7 mg Zn pot{sup -1}. We concluded that the phytoextraction performance of cultivars varies depending on the screening method used. - The phytoextraction performance of cultivars varies significantly depending on the screening method used.

Assessment of the phytoextraction potential of high biomass crop plants

International Nuclear Information System (INIS)

Hernandez-Allica, Javier; Becerril, Jose M.; Garbisu, Carlos

2008-01-01

A hydroponic screening method was used to identify high biomass crop plants with the ability to accumulate metals. Highest values of shoot accumulation were found in maize cv. Ranchero, rapeseed cv. Karat, and cardoon cv. Peralta for Pb (18 753 mg kg -1 ), Zn (10 916 mg kg -1 ), and Cd (242 mg kg -1 ), respectively. Subsequently, we tested the potential of these three cultivars for the phytoextraction of a metal spiked compost, finding out that, in cardoon and maize plants, increasing Zn and Cd concentrations led to lower values of root and shoot DW. By contrast, rapeseed shoot growth was not significantly affected by Cd concentration. Finally, a metal polluted soil was used to check these cultivars' phytoextraction capacity. Although the soil was phytotoxic enough to prevent the growth of cardoon and rapeseed plants, maize plants phytoextracted 3.7 mg Zn pot -1 . We concluded that the phytoextraction performance of cultivars varies depending on the screening method used. - The phytoextraction performance of cultivars varies significantly depending on the screening method used

A feasibility test to estimate the duration of phytoextraction of heavy metals from polluted soils

NARCIS (Netherlands)

Japenga, J.; Koopmans, G.F.; Song, J.; Romkens, P.F.A.M.

2007-01-01

The practical applicability of heavy metal (HM) phytoextraction depends heavily on its duration. Phytoextraction duration is the main cost factor for phytoextraction, both referring to recurring economic costs during phytoextraction and to the cost of the soil having no economic value during

Combined endophytic inoculants enhance nickel phytoextraction from serpentine soil in the hyperaccumulator Noccaea caerulescens

Directory of Open Access Journals (Sweden)

Giovanna eVisioli

2015-08-01

Full Text Available This study assesses the effects of specific bacterial endophytes on the phytoextraction capacity of the Ni-hyperaccumulator Noccaea caerulescens, spontaneously growing in a serpentine soil environment. Five metal-tolerant endophytes had already been selected for their high Ni tolerance (6 mM and plant growth promoting ability. Here we demonstrate that individual bacterial inoculation is ineffective in enhancing Ni translocation and growth of N. caerulescens in serpentine soil, except for specific strains Ncr-1 and Ncr-8, belonging to the Arthrobacter and Microbacterium genera, which showed the highest IAA production and ACC-deaminase activity. Ncr-1 and Ncr-8 co-inoculation was even more efficient in promoting plant growth, soil Ni removal and translocation of Ni, together with that of Fe, Co and Cu. Bacteria of both strains densely colonised the root surfaces and intercellular spaces of leaf epidermal tissue. These two bacterial strains also turned out to stimulate root length, shoot biomass and Ni uptake in Arabidopsis thaliana grown in MS agar medium supplemented with Ni. It is concluded that adaptation of N. caerulescens in highly Ni-contaminated serpentine soil can be enhanced by an integrated community of bacterial endophytes rather than by single strains; of the former, Arthrobacter and Microbacterium may be useful candidates for future phytoremediation trials

Phytoextraction of Heavy Metals from Soil Polluted with Waste Mining by Using Forage Plants in Successive Cultures

Directory of Open Access Journals (Sweden)

Anca Pricop

2010-10-01

Full Text Available During two years, was studied the phytoextraction potential of some perennial species (Medicago sativa and Trifolium pretense, Festuca arundinacea and Lolium perenne, for Zn, Cd, and Pb from soils polluted with waste mining. The experiment was done on kernozem soil with adding of 20 kg waste mining/m2 and 8 kg biosolid/m2. The results showed that in all experiments, rye-grass is a good extractor for Zn and Cd, and leguminous species for Pb. Both leguminous species, especially M. sativa, presented a high tolerance for lead toxicity, even with 3-4 times greater values than maximum allowable level from actual legislation. In all cases, regardless of the experimental variant, raygrass (Lolium perenne is a good accumulator of Zn and Cd, and red clover (Trifolium pratense of Pb. The values of metal bioaccumulation increase gradually with their concentration in soil. Quality of very good extractor of Pb displayed by Trifolium pratense species are kept even in case of excessive pollution with Pb, when it exceed 3.4 times the maximum permissible norms. This proves, as Medicago sativa species, a good tolerance and resistance to toxicity of this metal. In case of addition of natural zeolite-volcanic tuff there was no increase in the rate of Zn bioaccumulation. Only in case of Cd at Lolium perenne and Pb at Trifolium pratense appear the favourable effect of metallic ions bioavailability in soil for plants.

Phytoextraction of metals from soils: How far from practice?

International Nuclear Information System (INIS)

Nevel, Lotte van; Mertens, Jan; Oorts, Koen; Verheyen, Kris

2007-01-01

For most trace elements, the technique of phytoextraction needs significant improvements to become practically feasible. Calculations for Cd revealed that the amount of Cd taken up by Thlaspi caerulescens or Salix spp. needs at least to be the double of the present amount to slightly decrease the Cd concentration in the upper 0.5 m of the soil within a period of 10 years. Additionally, metals taken up by the plants might pose an important risk. Alternatives as bioavailable contaminant stripping and phytostabilization might be more appropriate. - Phytoextraction efficiency should be improved and associated risks need more attention before phytoextraction can be established as a commercial technology

Phytoextraction of metals from soils: How far from practice?

Energy Technology Data Exchange (ETDEWEB)

Nevel, Lotte van [Laboratory of Forestry, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, B-9090 Melle (Belgium)], E-mail: lotte.vannevel@ugent.be; Mertens, Jan [Laboratory of Forestry, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, B-9090 Melle (Belgium); Oorts, Koen [European Center for Risk Assessment Euras, Kortrijksesteenweg 302, B-9000 Ghent (Belgium); Verheyen, Kris [Laboratory of Forestry, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, B-9090 Melle (Belgium)

2007-11-15

For most trace elements, the technique of phytoextraction needs significant improvements to become practically feasible. Calculations for Cd revealed that the amount of Cd taken up by Thlaspi caerulescens or Salix spp. needs at least to be the double of the present amount to slightly decrease the Cd concentration in the upper 0.5 m of the soil within a period of 10 years. Additionally, metals taken up by the plants might pose an important risk. Alternatives as bioavailable contaminant stripping and phytostabilization might be more appropriate. - Phytoextraction efficiency should be improved and associated risks need more attention before phytoextraction can be established as a commercial technology.

Citric acid improves lead (pb) phytoextraction in brassica napus L. by mitigating pb-induced morphological and biochemical damages.

Science.gov (United States)

Shakoor, Muhammad Bilal; Ali, Shafaqat; Hameed, Amjad; Farid, Mujahid; Hussain, Sabir; Yasmeen, Tahira; Najeeb, Ullah; Bharwana, Saima Aslam; Abbasi, Ghulam Hasan

2014-11-01

Phytoextraction is an environmentally friendly and a cost-effective strategy for remediation of heavy metal contaminated soils. However, lower bioavailability of some of the metals in polluted environments e.g. lead (Pb) is a major constraint of phytoextraction process that could be overcome by applying organic chelators. We conducted a glasshouse experiment to evaluate the role of citric acid (CA) in enhancing Pb phytoextraction. Brassica napus L. seedlings were grown in hydroponic media and exposed to various treatments of Pb (50 and 100 μM) as alone or in combination with CA (2.5mM) for six weeks. Pb-induced damage in B. napus toxicity was evident from elevated levels of malondialdehyde (MDA) and H2O2 that significantly inhibited plant growth, biomass accumulation, leaf chlorophyll contents and gas exchange parameters. Alternatively, CA application to Pb-stressed B. napus plants arrested lipid membrane damage by limiting MDA and H2O2 production and by improving antioxidant enzyme activities. In addition, CA significantly increased the Pb accumulation in B. napus plants. The study concludes that CA has a potential to improve Pb phytoextraction without damaging plant growth. Copyright © 2014 Elsevier Inc. All rights reserved.

Willow trees from heavy metals phytoextraction as energy crops

International Nuclear Information System (INIS)

Šyc, Michal; Pohořelý, Michael; Kameníková, Petra; Habart, Jan; Svoboda, Karel; Punčochář, Miroslav

2012-01-01

Phytoextraction ability of some fast growing plant species leads to the idea of connecting biomass production with soil remediation of contaminated industrial zones and regions. This biomass will contain significant amount of heavy metals and its energetic utilization has to be considered carefully to minimize negative environmental impacts. This study was focused on potential disposal methods of willow trees contaminated by heavy metals (Cd, Cu, Pb, Zn) with the emphasis on energetic utilization of biomass. Composting seems to be suitable pre-treatment method resulting in decrease of heavy metals leachability and biomass weight reduction. The possibility of willow trees application for energetic purposes was investigated and consequently incineration tests of willow trees samples in fluidized bed reactor were realized. Distribution of selected heavy metals in different ash fractions and treatment methods of produced ashes were studied as well. -- Highlights: ► Composting is an appropriate pre-treatment method for phytoextraction crops. ► Fluidized bed combustion is suitable disposal method of phytoextraction crops. ► Ashes from phytoextraction crops combustion cannot be used as fertilizers.

Fresh organic matter of municipal solid waste enhances phytoextraction of heavy metals from contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Salati, S.; Quadri, G.; Tambone, F. [Dipartimento di Produzione Vegetale, Universita degli Studi di Milano, Via Celoria 2, 20133 Milano (Italy); Adani, F., E-mail: fabrizio.adani@unimi.i [Dipartimento di Produzione Vegetale, Universita degli Studi di Milano, Via Celoria 2, 20133 Milano (Italy)

2010-05-15

In this study, the ability of the organic fraction of municipal solid wastes (OFMSW) to enhance heavy metal uptake of maize shoots compared with ethylenediamine disuccinic acid (EDDS) was tested on soil contaminated with heavy metals. Soils treated with OFMSW and EDDS significantly increased the concentration of heavy metals in maize shoots (increments of 302%, 66%, 184%, 169%, and 23% for Cr, Cu, Ni, Zn, and Pb with respect to the control and increments of 933%, 482%, 928%, 428%, and 5551% for soils treated with OFMSW and EDDS, respectively). In soil treated with OFMSW, metal uptake was favored because of the high presence of dissolved organic matter (DOM) (41.6x than soil control) that exhibited ligand properties because of the high presence of carboxylic acids. Because of the toxic effect of EDDS on maize plants, soil treated with OFMSW achieved the highest extraction of total heavy metals. - Organic fraction of MSW affects the bioavailability of heavy metals in soil.

Fresh organic matter of municipal solid waste enhances phytoextraction of heavy metals from contaminated soil.

Science.gov (United States)

Salati, S; Quadri, G; Tambone, F; Adani, F

2010-05-01

In this study, the ability of the organic fraction of municipal solid wastes (OFMSW) to enhance heavy metal uptake of maize shoots compared with ethylenediamine disuccinic acid (EDDS) was tested on soil contaminated with heavy metals. Soils treated with OFMSW and EDDS significantly increased the concentration of heavy metals in maize shoots (increments of 302%, 66%, 184%, 169%, and 23% for Cr, Cu, Ni, Zn, and Pb with respect to the control and increments of 933%, 482%, 928%, 428%, and 5551% for soils treated with OFMSW and EDDS, respectively). In soil treated with OFMSW, metal uptake was favored because of the high presence of dissolved organic matter (DOM) (41.6x than soil control) that exhibited ligand properties because of the high presence of carboxylic acids. Because of the toxic effect of EDDS on maize plants, soil treated with OFMSW achieved the highest extraction of total heavy metals. Copyright 2009 Elsevier Ltd. All rights reserved.

Fresh organic matter of municipal solid waste enhances phytoextraction of heavy metals from contaminated soil

International Nuclear Information System (INIS)

Salati, S.; Quadri, G.; Tambone, F.; Adani, F.

2010-01-01

In this study, the ability of the organic fraction of municipal solid wastes (OFMSW) to enhance heavy metal uptake of maize shoots compared with ethylenediamine disuccinic acid (EDDS) was tested on soil contaminated with heavy metals. Soils treated with OFMSW and EDDS significantly increased the concentration of heavy metals in maize shoots (increments of 302%, 66%, 184%, 169%, and 23% for Cr, Cu, Ni, Zn, and Pb with respect to the control and increments of 933%, 482%, 928%, 428%, and 5551% for soils treated with OFMSW and EDDS, respectively). In soil treated with OFMSW, metal uptake was favored because of the high presence of dissolved organic matter (DOM) (41.6x than soil control) that exhibited ligand properties because of the high presence of carboxylic acids. Because of the toxic effect of EDDS on maize plants, soil treated with OFMSW achieved the highest extraction of total heavy metals. - Organic fraction of MSW affects the bioavailability of heavy metals in soil.

A feasibility test to estimate the duration of phytoextraction of heavy metals from polluted soils.

Science.gov (United States)

Japenga, J; Koopmans, G F; Song, J; Römkens, P F A M

2007-01-01

The practical applicability of heavy metal (HM) phytoextraction depends heavily on its duration. Phytoextraction duration is the main cost factorfor phytoextraction, both referring to recurring economic costs during phytoextraction and to the cost of the soil having no economic value during phytoextraction. An experiment is described here, which is meant as a preliminary feasibility test before starting a phytoextraction scheme in practice, to obtain a more realistic estimate of the phytoextraction duration of a specific HM-polluted soil. In the experiment, HM-polluted soil is mixed at different ratios with unpolluted soil of comparable composition to mimic the gradual decrease of the HM content in the target HM-polluted soil during phytoextraction. After equilibrating the soil mixtures, one cropping cycle is carried out with the plant species of interest. At harvest, the adsorbed HM contents in the soil and the HM contents in the plant shoots are determined. The adsorbed HM contents in the soil are then related to the HM contents in the plant shoots by a log-log linear relationship that can then be used to estimate the phytoextraction duration of a specific HM-polluted soil. This article describes and evaluates the merits of such a feasibility experiment. Potential drawbacks regarding the accuracy of the described approach are discussed and a greenhouse-field extrapolation procedure is proposed.

Combined endophytic inoculants enhance nickel phytoextraction from serpentine soil in the hyperaccumulator Noccaea caerulescens.

Science.gov (United States)

Visioli, Giovanna; Vamerali, Teofilo; Mattarozzi, Monica; Dramis, Lucia; Sanangelantoni, Anna M

2015-01-01

This study assesses the effects of specific bacterial endophytes on the phytoextraction capacity of the Ni-hyperaccumulator Noccaea caerulescens, spontaneously growing in a serpentine soil environment. Five metal-tolerant endophytes had already been selected for their high Ni tolerance (6 mM) and plant growth promoting ability. Here we demonstrate that individual bacterial inoculation is ineffective in enhancing Ni translocation and growth of N. caerulescens in serpentine soil, except for specific strains Ncr-1 and Ncr-8, belonging to the Arthrobacter and Microbacterium genera, which showed the highest indole acetic acid production and 1-aminocyclopropane-1-carboxylic acid-deaminase activity. Ncr-1 and Ncr-8 co-inoculation was even more efficient in promoting plant growth, soil Ni removal, and translocation of Ni, together with that of Fe, Co, and Cu. Bacteria of both strains densely colonized the root surfaces and intercellular spaces of leaf epidermal tissue. These two bacterial strains also turned out to stimulate root length, shoot biomass, and Ni uptake in Arabidopsis thaliana grown in MS agar medium supplemented with Ni. It is concluded that adaptation of N. caerulescens in highly Ni-contaminated serpentine soil can be enhanced by an integrated community of bacterial endophytes rather than by single strains; of the former, Arthrobacter and Microbacterium may be useful candidates for future phytoremediation trials in multiple metal-contaminated sites, with possible extension to non-hyperaccumulator plants.

Efficiency of biodegradable EDDS, NTA and APAM on enhancing the phytoextraction of cadmium by Siegesbeckia orientalis L. grown in Cd-contaminated soils.

Science.gov (United States)

Lan, Jichuan; Zhang, Shirong; Lin, Haichuan; Li, Ting; Xu, Xiaoxun; Li, Yun; Jia, Yongxia; Gong, Guoshu

2013-05-01

Chelant assisted phytoextraction has been proposed to enhance the efficiency of remediation. This study evaluated the effects of biodegradable ethylene diamine tetraacetate (EDDS), nitrilotriacetic (NTA) and anionic polyacrylamide (APAM) on the tolerance and uptake of Siegesbeckia orientalis L. at 10 and 100 mg kg(-1) Cd-contaminated soils. On the 80th and 90th days of transplanting, pots were treated with EDDS and NTA at 0 (control), 1 and 2 mmol kg(-1) soils, and APAM at 0 (control), 0.07 and 0.14 g kg(-1). Generally, the root and shoot biomass of S. orientalis in all treatments reduced not significantly compared with the control, and the activities of peroxidase and catalase in leaves generally increased by the application of chelants (P<0.05). The concentrations of Cd in the shoots were increased significantly by addition of all chelants. As a result, the Cd accumulation of S. orientalis under treatments with higher dosages of the three chelants on the 80th day were 1.40-2.10-fold and 1.12-1.25-fold compared to control at 10 and 100 mg kg(-1) Cd, respectively. Under the addition of 2 mmol kg(-1) NTA on the 80th day, the highest metal extraction ratio reached 1.2% and 0.4% at 10 and 100 mg kg(-1) Cd soils, respectively. Therefore, the applications of EDDS, NTA and APAM may provide more efficient choices in chemical-enhanced phytoextraction. Copyright © 2013 Elsevier Ltd. All rights reserved.

Phytoextraction of toxic metals: a central role for glutathione.

Science.gov (United States)

Seth, C S; Remans, T; Keunen, E; Jozefczak, M; Gielen, H; Opdenakker, K; Weyens, N; Vangronsveld, J; Cuypers, A

2012-02-01

Phytoextraction has a promising potential as an environmentally friendly clean-up method for soils contaminated with toxic metals. To improve the development of efficient phytoextraction strategies, better knowledge regarding metal uptake, translocation and detoxification in planta is a prerequisite. This review highlights our current understanding on these mechanisms, and their impact on plant growth and health. Special attention is paid to the central role of glutathione (GSH) in this process. Because of the high affinity of metals to thiols and as a precursor for phytochelatins (PCs), GSH is an essential metal chelator. Being an important antioxidant, a direct link between metal detoxification and the oxidative challenge in plants growing on contaminated soils is observed, where GSH could be a key player. In addition, as redox couple, oxidized and reduced GSH transmits specific information, in this way tuning cellular signalling pathways under environmental stress conditions. Possible improvements of phytoextraction could be achieved by using transgenic plants or plant-associated microorganisms. Joined efforts should be made to cope with the challenges faced with phytoextraction in order to successfully implement this technique in the field. © 2011 Blackwell Publishing Ltd.

Remediation of cadmium by Indian mustard (Brassica juncea L. from cadmium contaminated soil: a phytoextraction study

Directory of Open Access Journals (Sweden)

Rajeev Kumar Bhadkariya

2014-05-01

Full Text Available Cadmium is a toxic metal for living organisms and an environmental contaminant. Soils in many parts of the world are slightly too moderately contaminated by Cd due to long term use and disposal of Cd-contaminated wastes. Cost effective technologies are needed to remove cadmium from the contaminated sites. Soil phytoextraction is engineering based, low cost and socially accepted developing technology that uses plants to clean up contaminants in soils. This technology can be adopted as a remediation of cadmium from Cd-contaminated soils with the help of Brassica juncea plant. The objective of this work was to evaluate the cadmium (Cd accumulate and the tolerance of Brassica juncea. The Cd accumulates in all parts of plants (roots, stems and leaves. It was found that accumulating efficiency increased with the increase in the concentration of applied cadmium metal solution. Maximum accumulation of cadmium was found in roots than stem and leaves. Phytoextraction coefficient and translocation factor were highest to show the validity of the Brassica juncea species for hyperaccumulation of the Cd metal. These results suggested that Brassica juncea has a high ability to tolerate and accumulate Cd, so it might be a promising plant to be used for phytoextraction of Cd contaminated soil. DOI: http://dx.doi.org/10.3126/ije.v3i2.10533 International Journal of the Environment Vol.3(2 2014: 229-237

Rhizospheric Bacterial Strain Brevibacterium casei MH8a Colonizes Plant Tissues and Enhances Cd, Zn, Cu Phytoextraction by White Mustard.

Science.gov (United States)

Płociniczak, Tomasz; Sinkkonen, Aki; Romantschuk, Martin; Sułowicz, Sławomir; Piotrowska-Seget, Zofia

2016-01-01

Environmental pollution by heavy metals has become a serious problem in the world. Phytoextraction, which is one of the plant-based technologies, has attracted the most attention for the bioremediation of soils polluted with these contaminants. The aim of this study was to determine whether the multiple-tolerant bacterium, Brevibacterium casei MH8a isolated from the heavy metal-contaminated rhizosphere soil of Sinapis alba L., is able to promote plant growth and enhance Cd, Zn, and Cu uptake by white mustard under laboratory conditions. Additionally, the ability of the rifampicin-resistant spontaneous mutant of MH8a to colonize plant tissues and its mechanisms of plant growth promotion were also examined. In order to assess the ecological consequences of bioaugmentation on autochthonous bacteria, the phospholipid fatty acid (PLFA) analysis was used. The MH8a strain exhibited the ability to produce ammonia, 1-amino-cyclopropane-1-carboxylic acid deaminase, indole 3-acetic acid and HCN but was not able to solubilize inorganic phosphate and produce siderophores. Introduction of MH8a into soil significantly increased S. alba biomass and the accumulation of Cd (208%), Zn (86%), and Cu (39%) in plant shoots in comparison with those grown in non-inoculated soil. Introduced into the soil, MH8a was able to enter the plant and was found in the roots and leaves of inoculated plants thus indicating its endophytic features. PLFA analysis revealed that the MH8a that was introduced into soil had a temporary influence on the structure of the autochthonous bacterial communities. The plant growth-promoting features of the MH8a strain and its ability to enhance the metal uptake by white mustard and its long-term survival in soil as well as its temporary impact on autochthonous microorganisms make the strain a suitable candidate for the promotion of plant growth and the efficiency of phytoextraction.

Performance of bioaugmentation-assisted phytoextraction applied to metal contaminated soils: A review

Energy Technology Data Exchange (ETDEWEB)

Lebeau, Thierry [Equipe Depollution Biologique des Sols (EDBS), University of Haute-Alsace, 28, rue de Herrlisheim, BP 50 568, 68 008 Colmar Cedex (France)], E-mail: thierry.lebeau@uha.fr; Braud, Armelle; Jezequel, Karine [Equipe Depollution Biologique des Sols (EDBS), University of Haute-Alsace, 28, rue de Herrlisheim, BP 50 568, 68 008 Colmar Cedex (France)

2008-06-15

Bioaugmentation-assisted phytoextraction is a promising method for the cleaning-up of soils contaminated by metals. Bacteria mainly Plant Growth Promoting Rhizobacteria (PGPR) and fungi mainly Arbuscular Mycorrhizal Fungi (AMF) associated with hyperaccumulating or non-hyperaccumulating plants were analyzed on the basis of a bioprocess engineering approach (concentration and amount of metals extracted by plants, translocation and bioconcentration factor, and plant biomass). In average bioaugmentation increased metals accumulated by shoots by a factor of about 2 (metal concentration) and 5 (amount) without any obvious differences between bacteria and fungi. To optimize this process, new relevant microorganism-plant associations and field scale experiments are needed along with a common methodology for the comparison of all experiments on the same basis. Recommendations were suggested concerning both the microbial-plant selection and the implementation of bioaugmentation to enhance the microbial survival. The use of microbial consortia associated with plant was discussed notably for multi-contaminated soils. - Bioaugmentation-assisted plant improves the phytoextraction performances for soils contaminated by metals.

Performance of bioaugmentation-assisted phytoextraction applied to metal contaminated soils: A review

International Nuclear Information System (INIS)

Lebeau, Thierry; Braud, Armelle; Jezequel, Karine

2008-01-01

Bioaugmentation-assisted phytoextraction is a promising method for the cleaning-up of soils contaminated by metals. Bacteria mainly Plant Growth Promoting Rhizobacteria (PGPR) and fungi mainly Arbuscular Mycorrhizal Fungi (AMF) associated with hyperaccumulating or non-hyperaccumulating plants were analyzed on the basis of a bioprocess engineering approach (concentration and amount of metals extracted by plants, translocation and bioconcentration factor, and plant biomass). In average bioaugmentation increased metals accumulated by shoots by a factor of about 2 (metal concentration) and 5 (amount) without any obvious differences between bacteria and fungi. To optimize this process, new relevant microorganism-plant associations and field scale experiments are needed along with a common methodology for the comparison of all experiments on the same basis. Recommendations were suggested concerning both the microbial-plant selection and the implementation of bioaugmentation to enhance the microbial survival. The use of microbial consortia associated with plant was discussed notably for multi-contaminated soils. - Bioaugmentation-assisted plant improves the phytoextraction performances for soils contaminated by metals

Phytoextraction studies for removal of 239Pu using Vetiveria zizanoides plants

International Nuclear Information System (INIS)

Singh, Shraddha; Fulzele, D.P.; Kaushik, C.P.

2015-01-01

The potential of Vetiveria zizanoides, a plant used for environmental conservation was tested for remediation of radionuclide plutonium ( 239 Pu). While the plant could remediate high levels of 239 Pu (65%) from solutions, remediation of radionuclides from soil was limited. Addition of chelating agents such as citric acid (CA) and diethylenetriaminepentaacetic acid (DTPA) enhanced phytoremediation of 239 Pu from soil. Translocation of 239 Pu to the shoot biomass showed an enhancement in the presence of chelating agents. The present studies have shown that V. zizanoides is a suitable candidate plant for remediation of 239 Pu and addition of DTPA enhanced translocation of radionuclide to shoot which may further lead to phytoextraction. (author)

Remediation of cadmium by Indian mustard (Brassica juncea L.) from cadmium contaminated soil: a phytoextraction study

OpenAIRE

Rajeev Kumar Bhadkariya; VK Jain; GPS Chak; SK Gupta

2014-01-01

Cadmium is a toxic metal for living organisms and an environmental contaminant. Soils in many parts of the world are slightly too moderately contaminated by Cd due to long term use and disposal of Cd-contaminated wastes. Cost effective technologies are needed to remove cadmium from the contaminated sites. Soil phytoextraction is engineering based, low cost and socially accepted developing technology that uses plants to clean up contaminants in soils. This technology can be adopted as a remedi...

Impact of chelator-induced phytoextraction of cadmium on yield and ionic uptake of maize.

Science.gov (United States)

Anwar, Sumera; Khan, Shahbaz; Ashraf, M Yasin; Noman, Ali; Zafar, Sara; Liu, Lijun; Ullah, Sana; Fahad, Shah

2017-06-03

Enhanced phytoextraction uses soil chelators to increase the bioavailability of heavy metals. This study tested the effectiveness of ethylenediaminetetraacetic acid (EDTA) and citric acid in enhancing cadmium (Cd) phytoextraction and their effects on the growth, yield, and ionic uptake of maize (Zea mays). Maize seeds of two cultivars were sown in pots treated with 15 (Cd 15 ) or 30 mg Cd kg -1 soil (Cd 30 ). EDTA and citric acid at 0.5 g kg -1 each were applied 2 weeks after germination. Results demonstrated that the growth, yield per plant, and total grain weight were reduced by exposure to Cd. EDTA increased the uptake of Cd in shoots, roots, and grains of both maize varieties. Citric acid did not enhance the uptake of Cd, rather it ameliorated the toxicity of Cd, as shown by increased shoot and root length and biomass. Cadmium toxicity reduced the number of grains, rather than the grain size. The maize cultivar Sahiwal-2002 extracted 1.6% and 3.6% of Cd from soil in both Cd+ EDTA treatments. Hence, our study implies that maize can be used to successfully phytoremediate Cd from soil using EDTA, without reducing plant biomass or yield.

Phytoextraction of excess soil phosphorus

International Nuclear Information System (INIS)

Sharma, Nilesh C.; Starnes, Daniel L.; Sahi, Shivendra V.

2007-01-01

In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils

Phytoextraction of excess soil phosphorus

Energy Technology Data Exchange (ETDEWEB)

Sharma, Nilesh C. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Starnes, Daniel L. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Sahi, Shivendra V. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States)]. E-mail: shiv.sahi@wku.edu

2007-03-15

In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils.

Repeated phytoextraction of four metal-contaminated soils using the cadmium/zinc hyperaccumulator Sedum plumbizincicola.

Science.gov (United States)

Li, Zhu; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Zhang, Hao; Christie, Peter

2014-06-01

A cadmium/zinc hyperaccumulator extracted metals from four contaminated soils over three years in a glasshouse experiment. Changes in plant metal uptake and soil total (aqua regia-extractable) and available metals were investigated. Plant Cd concentrations in a high-Cd acid soil and plant Zn concentrations in two acid soils decreased during repeated phytoextraction and were predicted by soil available metal concentrations. However, on repeated phytoextraction, plant Cd concentrations remained constant in lightly Cd-polluted acid soils, as did plant Cd and Zn in alkaline soils, although soil available metal concentrations decreased markedly. After phytoextraction acid soils showed much higher total metal removal efficiencies, indicating possible suitability of phytoextraction for acid soils. However, DGT-testing, which takes soil metal re-supply into consideration, showed substantial removal of available metal and distinct decreases in metal supply capacity in alkaline soils after phytoextraction, suggesting that a strategy based on lowering the bioavailable contaminant might be feasible. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of plant growth regulators to increase nickel phytoextraction by Alyssum species.

Science.gov (United States)

Cabello-Conejo, M I; Centofanti, T; Kidd, P S; Prieto-Fernández, A; Chaney, R L

2013-01-01

Recent studies have shown that application of phytohormones to shoots of Alyssum murale increased biomass production but did not increase Ni shoot concentration. Increased biomass and Ni phytoextraction efficiency is useful to achieve economically viable phytomining. The objective of this study was to evaluate the effect of two types of phytohormones on the Ni phytoextraction capacity of four Alyssum species. Two different commercially available phytohormones (Cytokin and Promalin) based on cytokinins and/or gibberellins were applied on shoot biomass of four Ni hyperaccumulating Alyssum species (A. corsicum, A. malacitanum, A. murale, and A. pintodasilvae). Cytokin was applied in two concentrations and promalin in one concentration. The application of phytohormones had no clear positive effect on biomass production, Ni accumulation and Ni phytoextraction efficiency in the studied Alyssum species. A. malacitanum was the only species in which a significantly negative effect of these treatments was observed (in Ni uptake). A slightly positive response to promalin treatment was observed in the biomass production and Ni phytoextraction efficiency of A. corsicum. Although this effect was not significant it does indicate a potential application of these approaches to improve phytoextraction ability. Further studies will be needed to identify the most adequate phytohormone treatment as well as the appropriate concentrations and application times.

Effect of mycorrhizal fungi on the phytoextraction of weathered p,p-DDE by Cucurbita pepo.

Science.gov (United States)

White, Jason C; Ross, Daniel W; Gent, Martin P N; Eitzer, Brian D; Mattina, Maryjane Incorvia

2006-10-11

Field experiments were conducted to assess the impact of inoculation with mycorrhizal fungi on the accumulation of weathered p,p'-DDE from soil by three cultivars of zucchini (Cucurbita pepo spp. pepo cv Costata Romanesco, Goldrush, Raven). Three commercially available mycorrhizal products (BioVam, Myco-Vam, INVAM) were inoculated into the root system of the zucchini seedlings at planting. In agreement with our previous findings, plants not inoculated with fungi accumulated large but variable amounts of contaminant, with root bioconcentration factors (BCFs, ratio of p,p'-DDE, on a dry weight basis, in the root to that in the soil) ranging from 10 to 48 and stem BCFs ranging from 5.5 to 11. The total amount of contaminant phytoextracted during the 62 day growing season ranged from 0.72-2.9%. The effect of fungal inoculation on the release of weathered p,p'-DDE from soil and on the subsequent uptake of the parent compound by zucchini appeared to vary at the cultivar level. For Goldrush, fungal inoculation generally decreased tissue BCFs but because of slightly larger biomass, did not significantly impact the percent contaminant phytoextracted. Alternatively, for Costata, BioVam and Myco-Vam generally enhanced p,p'-DDE accumulation from soil, and increased the amount of contaminant phytoextracted by up to 34%. For Raven, BioVam reduced contaminant uptake whereas Myco-Vam and INVAM increased contaminant phytoextraction by 53 and 60%, respectively. The data show that fungal inoculation may significantly increase the remedial potential of C. pepo ssp. pepo. The apparent cultivar specific response to mycorrhizal inoculation is unexpected and the subject of ongoing investigation.

Rhizospheric bacterial strain Brevibacterium casei MH8a colonizes plant tissues and enhances Cd, Zn, Cu phytoextraction by white mustard

Directory of Open Access Journals (Sweden)

Tomasz ePłociniczak

2016-02-01

Full Text Available Environmental pollution by heavy metals has become a serious problem in the world. Phytoextraction, which is one of the plant-based technologies, has attracted the most attention for the bioremediation of soils polluted with these contaminants.The aim of this study was to determine whether the multiple-tolerant bacterium, Brevibacterium casei MH8a isolated from the heavy metal-contaminated rhizosphere soil of Sinapis alba L., is able to promote plant growth and enhance Cd, Zn and Cu uptake by white mustard under laboratory conditions. Additionally, the ability of the rifampicin-resistant spontaneous mutant of MH8a to colonize plant tissues and its mechanisms of plant growth promotion were also examined. In order to assess the ecological consequences of bioaugmentation on autochthonous bacteria, the phospholipid fatty acid (PLFA analysis was used. The MH8a strain exhibited the ability to produce ammonia, 1-amino-cyclopropane-1-carboxylic acid deaminase, indole 3-acetic acid and HCN but was not able to solubilize inorganic phosphate and produce siderophores. Introduction of MH8a into soil significantly increased S. alba biomass and the accumulation of Cd (208%, Zn (86% and Cu (39% in plant shoots in comparison with those grown in non-inoculated soil. Introduced into the soil, MH8a was able to enter the plant and was found in the roots and leaves of inoculated plants thus indicating its endophytic features. PLFA analysis revealed that the MH8a that was introduced into soil had a temporary influence on the structure of the autochthonous bacterial communities. The plant growth-promoting features of the MH8a strain and its ability to enhance the metal uptake by white mustard and its long-term survival in soil as well as its temporary impact on autochthonous microorganisms make the strain a suitable candidate for the promotion of plant growth and the efficiency of phytoextraction.

Inheritance of p,p'-DDE phytoextraction ability in hybridized Cucurbita pepo cultivars.

Science.gov (United States)

White, Jason C

2010-07-01

Cucurbita pepo ssp pepo (zucchini) has been shown to uniquely phytoextract percent level amounts of dichlorodiphenyldichloroethylene (DDE) and other organic contaminants from soil. Since C. pepo ssp ovifera (squash) does not have this ability, a three-year field trial was conducted to follow the inheritance pattern of DDE accumulation for cross pollinated C. pepo cultivars. Parental zucchini and squash cultivars (3 each) had stem-to-soil bioconcentration factors (BCF, contaminant ratio of stem to soil) of 16 and 1.7, respectively, and phytoextracted 1.8 and 0.18% of the DDE from soil. The 18 possible first filial (F1) hybrids of zucchini and squash accumulated significantly different DDE levels than the respective parents. The zucchini F1 hybrid (zucchini pollinated with squash) stem BCFs and percent phytoextraction values were 10 and 0.96, respectively, or 36% and 47% less than the parental zucchini. The squash F1 hybrid (squash pollinated with zucchini) stem BCFs and percent phytoextraction values were 8.3 and 0.68, respectively, or 490% and 370% greater than the parental squash. When backcrossed (BC) with the original parent, the nine zucchini F1 BC cultivars did not regain the capability to take up DDE; stem BCFs and percent phytoextraction values were equivalent to those of the F1 generation. However, the nine squash F1 BC cultivars lost much of the DDE uptake capability of the F1 generation; stem BCFs and percent phytoextraction values were intermediate but closer to those of the parental squash. The inheritance patterns suggest single locus control for persistent organic pollutant (POP) uptake ability in C. pepo ssp pepo.

Chemically assisted phytoextraction: a review of potential soil amendments for increasing plant uptake of heavy metals.

Science.gov (United States)

Meers, E; Tack, F M G; Van Slycken, S; Ruttens, A; Du Laing, G; Vangronsveld, J; Verloo, M G

2008-01-01

The contamination of soils by trace metals has been an unfortunate sideeffect of industrialization. Some of these contaminants can interfere with vulnerable enduses of soil, such as agriculture or nature, already at relatively low levels of contamination. Reversely, conventional civil-technical soil-remediation techniques are too expensive to remediate extended areas of moderately contaminated soil. Phytoextraction has been proposed as a more economic complementary approach to deal with this specific niche of soil contamination. However, phytoextraction has been shown to be a slow-working process due to the low amounts of metals that can be annually removed from the soil under normal agronomic conditions. Therefore, extensive research has been conducted on process optimization by means of chemically improving plant availability and the uptake of heavy metals. A wide range of potential amendments has been proposed in the literature, with considerable attention being spent on aminopolycarboxylic acids such as ethylenediaminetetraacetic acid (EDTA). However, these compounds have received increasing criticism due to their environmental persistence and associated risks for leaching. This review presents an overview of potential soil amendments that can be employed for enhancing metal uptake by phytoextraction crops, with a distinct focus on more degradable alternatives to persistent compounds such as EDTA.

Applicability of Phytoextraction with Arabidopsis halleri ssp. gemmifera to Remediate Cd-contaminated Andisols

Science.gov (United States)

Kameyama, Koji; Tani, Shigeru; Sugawara, Reiko; Ishikawa, Yuichi

The objective of this study was to investigate the applicability of phytoextraction with a Cd-hyperaccumulator plant (Arabidopsis halleri ssp. gemmifera) to remediate Cd-contaminated Andisols. Cd absorption potentials of this plant for Andisols were examined in pot experiments. Sequentially, phytoextraction durations for remediation of Cd-contaminated Andisols were calculated from the experimental data. The results were as follows: (1) Cd concentrations in the plant shoots ranged from 170-750 mgṡkg-1. (2) Cd absorption of the plant for Andisols with ALC (Autoclaved Lightweight aerated Concrete) was less than for Andisols without ALC. However, the plants absorbed the same amount of soil Cd extracted by 0.01 M HCl with or without ALC. (3) Calculations suggest that the applicability of phytoextraction with this plant is high for slightly contaminated Andisols. Therefore, phytoextraction with Arabidopsis halleri ssp. gemmifera may be a viable option for the remediation of Cd-contaminated Andisols.

Phytoextraction of Cd-Contaminated Soils: Current Status and Future Challenges

OpenAIRE

Li, Jin-Tian; Baker, Alan J. M.; Ye, Zhi-Hong; Wang, Hong-Bin; Shu, Wen-Sheng

2012-01-01

Cadmium (Cd) is one of the most toxic and widely distributed pollutants in the environment. Cadmium contamination of soils has posed a serious threat to safe food production in many parts of the world. The authors present a comprehensive review of present status of phytoextraction technology for cleaning up Cd-contaminated soils, based primarily on the data resulting from both laboratory and field-scale studies that have been conducted to assess or improve the Cd phytoextraction potential of ...

Heavy metal phytoextraction by Sedum alfredii is affected by continual clipping and phosphorus fertilization amendment.

Science.gov (United States)

Huang, Huagang; Li, Tingqiang; Gupta, D K; He, Zhenli; Yang, Xiao-E; Ni, Bingnan; Li, Mao

2012-01-01

Improving the efficacy of phytoextraction is critical for its successful application in metal contaminated soils. Mineral nutrition affects plant growth and metal absorption and subsequently the accumulation of heavy metal through hyper-accumulator plants. This study assessed the effects of di-hydrogen phosphates (KH2PO4, Ca(H2PO4)2, NaH2PO4 and NH4H2PO4) application at three levels (22, 88 and 352 mg P/kg soil) on Sedum alfredii growth and metal uptake by three consecutive harvests on aged and Zn/Cd combined contaminated paddy soil. The addition of phosphates (P) significantly increased the amount of Zn taken up by S. alfredii due to increased shoot Zn concentration and dry matter yield (DMY) (P phytoextraction of Zn and Cd was observed in KH2PO4 and NH4H2PO4 treatment at 352 mg P/kg soil. The amount of Zn removed by phytoextraction increased in the order of 1st clipping < 2nd clipping < 3rd clipping, and for Cd extraction the order was 2nd clipping < 1st clipping < 3rd clipping. These results indicate that the application of P fertilizers coupled with multiple cuttings can enhance the removal of Zn and Cd from contaminated soils by S. alfredii, thus shortening the time needed for accomplishing remediation goals.

Phytoextraction of heavy metals by potential native plants and their microscopic observation of root growing on stabilised distillery sludge as a prospective tool for in situ phytoremediation of industrial waste.

Science.gov (United States)

Chandra, Ram; Kumar, Vineet

2017-01-01

The safe disposal of post-methanated distillery sludge (PMDS) in the environment is challenging due to high concentrations of heavy metals along with other complex organic pollutants. The study has revealed that PMDS contained high amounts of Fe (2403), Zn (210), Mn (126), Cu (73.62), Cr (21.825), Pb (16.33) and Ni (13.425 mg kg -1 ) along with melanoidins and other co-pollutants. The phytoextraction pattern in 15 potential native plants growing on sludge showed that the Blumea lacera, Parthenium hysterophorous, Setaria viridis, Chenopodium album, Cannabis sativa, Basella alba, Tricosanthes dioica, Amaranthus spinosus L., Achyranthes sp., Dhatura stramonium, Sacchrum munja and Croton bonplandianum were noted as root accumulator for Fe, Zn and Mn, while S. munja, P. hysterophorous, C. sativa, C. album, T. dioica, D. stramonium, B. lacera, B. alba, Kalanchoe pinnata and Achyranthes sp. were found as shoot accumulator for Fe. In addition, A. spinosus L. was found as shoot accumulator for Zn and Mn. Similarly, all plants found as leaf accumulator for Fe, Zn and Mn except A. spinosus L. and Ricinus communis. Further, the BCF of all tested plants were noted 1. This revealed that metal bioavailability to plant is poor due to strong complexation of heavy metals with organic pollutants. This gives a strong evidence of hyperaccumulation for the tested metals from complex distillery waste. Furthermore, the TEM observations of root of P. hysterophorous, C. sativa, Solanum nigrum and R. communis showed formation of multi-nucleolus, multi-vacuoles and deposition of metal granules in cellular component of roots as a plant adaptation mechanism for phytoextraction of heavy metal-rich polluted site. Hence, these native plants may be used as a tool for in situ phytoremediation and eco-restoration of industrial waste-contaminated site.

Feasibility of phytoextraction to remediate cadmium and zinc contaminated soils

International Nuclear Information System (INIS)

Koopmans, G.F.; Roemkens, P.F.A.M.; Fokkema, M.J.; Song, J.; Luo, Y.M.; Japenga, J.; Zhao, F.J.

2008-01-01

A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and Zn exceeded the decrease of the soluble metal concentrations by several orders of magnitude. Hence, desorption of metals must have occurred to maintain the soil solution concentrations. A coupled regression model was developed to describe the transfer of metals from soil to solution and plant shoots. This model was applied to estimate the phytoextraction duration required to decrease the soil Cd concentration from 10 to 0.5 mg kg -1 . A biomass production of 1 and 5 t dm ha -1 yr -1 yields a duration of 42 and 11 yr, respectively. Successful phytoextraction operations based on T. caerulescens require an increased biomass production. - An experimental method is presented to be used to estimate the phytoextraction duration of a metal contaminated soil

Use of non-hyperaccumulator plant species for the phytoextraction of heavy metals using chelating agents

Directory of Open Access Journals (Sweden)

Lucas Anjos Souza

2013-08-01

Full Text Available Soil contamination by heavy metals is a challenge faced by many countries, and engineering technologies to solve this problem are expensive and can cause negative impacts on the environment. One way to minimise the levels of heavy metals in the soil is to use plants that can absorb and accumulate heavy metals into harvestable parts, a process called phytoextraction. Typical plant species used in research involving phytoextraction are heavy metal hyperaccumulators, but plants from this group are not good biomass producers and grow more slowly than most species; thus, they have an important role in helping scientists understand the mechanisms involved in accumulating high amounts of heavy metals without developing symptoms or dying. However, because of their slow growth, it is not practical to use these species for phytoextraction. An alternative approach is to use non-hyperaccumulator plants assisted by chelating agents, which may improve the ability of plants to accumulate more heavy metals than they would naturally. Chelating agents can be synthetic or organic acids, and the advantages and disadvantages of their use in improving the phytoextraction potential of non-hyperaccumulator plants are discussed in this article. We hope to draw attention to ways to improve the phytoextraction potential of non-hyperaccumulator plants that produce a large amount of biomass and to stimulate more research on phytoextraction-inducing substances.

The use of chelating agents in the remediation of metal-contaminated soils: A review

Energy Technology Data Exchange (ETDEWEB)

Lestan, Domen [Agronomy Department, Centre for Soil and Environmental Science, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana (Slovenia); Luo Chunling [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Li Xiangdong [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)], E-mail: cexdli@polyu.edu.hk

2008-05-15

This paper reviews current remediation technologies that use chelating agents for the mobilization and removal of potentially toxic metals from contaminated soils. These processes can be done in situ as enhanced phytoextraction, chelant enhanced electrokinetic extraction and soil flushing, or ex situ as the extraction of soil slurry and soil heap/column leaching. Current proposals on how to treat and recycle waste washing solutions after soil is washed are discussed. The major controlling factors in phytoextraction and possible strategies for reducing the leaching of metals associated with the application of chelants are also reviewed. Finally, the possible impact of abiotic and biotic soil factors on the toxicity of metals left after the washing of soil and enhanced phytoextraction are briefly addressed. - The use of synthetic chelants for soil washing and enhanced phytoextraction by plants has been well studied for the remediation of metal-contaminated soils in the last two decades.

The use of chelating agents in the remediation of metal-contaminated soils: A review

International Nuclear Information System (INIS)

Lestan, Domen; Luo Chunling; Li Xiangdong

2008-01-01

This paper reviews current remediation technologies that use chelating agents for the mobilization and removal of potentially toxic metals from contaminated soils. These processes can be done in situ as enhanced phytoextraction, chelant enhanced electrokinetic extraction and soil flushing, or ex situ as the extraction of soil slurry and soil heap/column leaching. Current proposals on how to treat and recycle waste washing solutions after soil is washed are discussed. The major controlling factors in phytoextraction and possible strategies for reducing the leaching of metals associated with the application of chelants are also reviewed. Finally, the possible impact of abiotic and biotic soil factors on the toxicity of metals left after the washing of soil and enhanced phytoextraction are briefly addressed. - The use of synthetic chelants for soil washing and enhanced phytoextraction by plants has been well studied for the remediation of metal-contaminated soils in the last two decades

Long-term field metal extraction by Pelargonium: phytoextraction efficiency in relation to plant maturity.

Science.gov (United States)

Shahid, Muhammad; Arshad, Muhammad; Kaemmerer, Michel; Pinelli, Eric; Probst, Anne; Baque, David; Pradere, Philippe; Dumat, Camille

2012-01-01

The long length of periods required for effective soil remediation via phytoextraction constitutes a weak point that reduces its industrial use. However, these calculated periods are mainly based on short-term and/or hydroponic controlled experiments. Moreover, only a few studies concern more than one metal, although soils are scarcely polluted by only one element. In this scientific context, the phytoextraction of metals and metalloids (Pb, Cd, Zn, Cu, and As) by Pelargonium was measured after a long-term field experiment. Both bulk and rhizosphere soils were analyzed in order to determine the mechanisms involved in soil-root transfer. First, a strong increase in lead phytoextraction was observed with plant maturity, significantly reducing the length of the period required for remediation. Rhizosphere Pb, Zn, Cu, Cd, and As accumulation was observed (compared to bulk soil), indicating metal mobilization by the plant, perhaps in relation to root activity. Moreover, metal phytoextraction and translocation were found to be a function of the metals' nature. These results, taken altogether, suggest that Pelargonium could be used as a multi-metal hyperaccumulator under multi-metal soil contamination conditions, and they also provide an interesting insight for improving field phytoextraction remediation in terms of the length of time required, promoting this biological technique.

Phytoextraction of uranium and thorium by native trees in a contaminated wetland

International Nuclear Information System (INIS)

Hinton, T.G.; Sharitz, R.

2005-01-01

The phytoremediation potential of native trees in a U and Th contaminated wetland was examined. Based on measurements of the annual biomass of leaves and their contaminant concentrations, we estimated the reduction in soil contamination over time. Significant differences among tree species were found, with tupelo (Nyssa sylvatica) and sweetgum (Liquidambar styraciflua) having a significantly greater capacity to remove U and Th from the soil than the other tree species. More U was phytoextracted than Th from the site. Phytoextraction rate constants were developed and revealed that although U and Th phytoextraction was exceptionally high at the site, an order of magnitude greater than predicted, the community of native trees would lower the soil inventory of 238 U and 232 Th by only 1% over the next 100 years. (author)

Feasibility of phytoextraction to remediate cadmium and zinc contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Koopmans, G.F. [Department of Soil Quality, Wageningen University, Wageningen University and Research Centre (WUR), P.O. Box 47, 6700 AA, Wageningen (Netherlands)], E-mail: gerwin.koopmans@wur.nl; Roemkens, P.F.A.M.; Fokkema, M.J. [Alterra, WUR, P.O. Box 47, 6700 AA, Wageningen (Netherlands); Song, J.; Luo, Y.M. [Soil and Environmental Bioremediation Research Centre, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Japenga, J. [Alterra, WUR, P.O. Box 47, 6700 AA, Wageningen (Netherlands); Zhao, F.J. [Soil Science Department, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom)

2008-12-15

A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and Zn exceeded the decrease of the soluble metal concentrations by several orders of magnitude. Hence, desorption of metals must have occurred to maintain the soil solution concentrations. A coupled regression model was developed to describe the transfer of metals from soil to solution and plant shoots. This model was applied to estimate the phytoextraction duration required to decrease the soil Cd concentration from 10 to 0.5 mg kg{sup -1}. A biomass production of 1 and 5 t dm ha{sup -1} yr{sup -1} yields a duration of 42 and 11 yr, respectively. Successful phytoextraction operations based on T. caerulescens require an increased biomass production. - An experimental method is presented to be used to estimate the phytoextraction duration of a metal contaminated soil.

Modeling phytoextraction of heavy metals at multiply contaminated soils with hyperaccumulator plants

OpenAIRE

Khodaverdiloo, Habib

2009-01-01

Soils and waters contaminated with heavy metals pose a major environmental and human health problem that needs an effective and affordable technological solution. Phytoextraction offers a reasonable technology which uses plants to extract the heavy metals from soils. However, the effectiveness of this new method needs to be demonstrated by means of mathematical modeling. The phytoextraction models also are needed to manage the contaminated soils. A thorough literature review indic...

Phytoextraction from mine spoils: insights from New Caledonia.

Science.gov (United States)

Losfeld, Guillaume; Mathieu, Romain; L'Huillier, Laurent; Fogliani, Bruno; Jaffré, Tanguy; Grison, Claude

2015-04-01

Increasing pressure on mineral resources has drawn research efforts into innovative supply and recycling. Metal-rich biomass produced in phytoextraction recently proved an interesting starting material for green chemistry. It allows the production of new catalysts, referred to as ecocatalysts. Ecocatalysts provide increased yields in chemical production and increased regio- and chemo-selectivity, which result in high added value. This new approach to using metal-rich biomass could spur the development of phytoextraction, a technique considered promising for long, yet without credible economic outlets. In this regard, metallophyte biodiversity hotspots, such as New Caledonia, are of particular interest for biomass supply. Potential phytoextraction from mine spoils using two species endemic to New Caledonia is discussed here. Geissois pruinosa, a hypernickelophore, and Grevillea exul, a Mn accumulator, were selected for these original experiments. The results presented here 20 months after plantation of young trees from a nursery show the interest of the approach. Mean Ni concentrations of up to 1513 mg kg(-1) are reported in G. pruinosa, as well as 2000 mg kg(-1) Mn in G. exul. Concentrations of Ni and Mn in the leaves of each species appear to be correlated with leaf age. Plantation of these species may also ensure mine reclamation, and experiments were conducted with the principles of ecological restoration in mind adding a further dimension to the approach.

"Towards practical cadmium phytoextraction with Thlaspi caerulescens"

Science.gov (United States)

During 2005-2007, a series of field trials were conducted to investigate the potential of Thlapsi caerulescens ecotypes derived from southern France to phytoextract localized Cd/Zn contamination in Thailand. Soil treatments included pH variation and fertilization level. T. caerulescens ecotypes w...

Potassium solubilizing bacteria-assisted phytoextraction of radiocesium on pechay plants grown in cesium contaminated Fukushima Soils

International Nuclear Information System (INIS)

Rallos, R.V.; Yokoyama, T.

2015-01-01

Increasing the efficiency of metal uptake by plants is important to achieve successful phytoremediation of metal-polluted soils. The presence of potassium solubilizing bacteria (KSB) increases the solubilization of K-containing minerals thereby enhancing the availability of potassium (K+) and other cations including radicesium (137Cs+) for plant uptake. In this study, five KSB isolates were obtained from soybean rhizosphere in Fukushima radiocesium contaminated soils. Based on biochemical and 16S rRNA gene sequence analysis, the bacteria were identified as Bacillus megaterium, Pseudomonas putida, P. frederiksbergensis, Burkholderia sabiae, and P. mandelii. The KSB isolates were evaluated for plant growth promotion, potassium (K) uptake and radiocesium phytoextraction of pechay in three different cesium-contaminated Fukushima soils. Inoculation with KSB showed beneficial effects on plant growth and increased the phytoextraction of radiocesium, with much greater magnitude in roots than in shoots. The results indicated that KSB inoculation may be essential in managing radiocesium-contaminated soils and manipulating the transfer from soils to plants.(author)

A comparative study of cadmium phytoextraction by accumulator and weed species

International Nuclear Information System (INIS)

Ghosh, Moyukh; Singh, S.P.

2005-01-01

Phytoextraction has shown great potential as an alternative technique for the remediation of metal contaminated soils. The objective of this study was to investigate cadmium (Cd) phytoextraction ability of high biomass producing weeds in comparison to indicator plant species. The pot study conducted with 10 to 200 mg Cd kg -1 soil indicated that Ipomoea carnea was more effective in removing Cd from soil than Brassica juncea. Among the five species, B. juncea accumulated maximum Cd, but I. carnea followed by Dhatura innoxia and Phragmytes karka were the most suitable species for phytoextraction of cadmium from soil, if the whole plant or above ground biomass is harvested. In the relatively short time of this experiment, I. carnea produced more than 5 times more biomass in comparison to B. juncea. There were significant differences (p < 0.05) between the shoot length and shoot mass of control and treated plants. - Ipomoea carnea was more effective in extracting cadmium than was Brassica juncea

Modeling of phytoextraction efficiency of microbially stimulated Salix dasyclados L. in the soils with different speciation of heavy metals.

Science.gov (United States)

Złoch, Michał; Kowalkowski, Tomasz; Tyburski, Jarosław; Hrynkiewicz, Katarzyna

2017-12-02

Bioaugmentation of soils with selected microorganisms during phytoextraction can be the key solution for successful bioremediation and should be accurately calculated for different physicochemical soil properties and heavy metal availability to guarantee the universality of this method. Equally important is the development of an accurate prediction tool to manage phytoremediation process. The main objective of this study was to evaluate the role of three metallotolerant siderophore-producing Streptomyces sp. B1-B3 strains in the phytoremediation of heavy metals with the use of S. dasyclados L. growing in four metalliferrous soils as well as modeling the efficiency of this process based on physicochemical and microbiological properties of the soils using artificial neural network (ANN) analysis. The bacterial inoculation of plants significantly stimulated plant biomass and reduced oxidative stress. Moreover, the bacteria affected the speciation of heavy metals and finally their mobility, thereby enhancing the uptake and bioaccumulation of Zn, Cd, and Pb in the biomass. The best capacity for phytoextraction was noted for strain B1, which had the highest siderophore secretion ability. Finally, ANN model permitted to predict efficiency of phytoextraction based on both the physicochemical properties of the soils and the activity of the soil microbiota with high precision.

Phytoextraction of heavy metals by canola (Brassica napus) and radish (Raphanus sativus) grown on multicontaminated soil.

Science.gov (United States)

Marchiol, L; Assolari, S; Sacco, P; Zerbi, G

2004-11-01

Phytoextraction can provide an effective in situ technique for removing heavy metals from polluted soils. The experiment reported in this paper was undertaken to study the basic potential of phytoextraction of Brassica napus (canola) and Raphanus sativus (radish) grown on a multi-metal contaminated soil in the framework of a pot-experiment. Chlorophyll contents and gas exchanges were measured during the experiment; the heavy metal phytoextraction efficiency of canola and radish were also determined and the phytoextraction coefficient for each metal calculated. Data indicated that both species are moderately tolerant to heavy metals and that radish is more so than canola. These species showed relatively low phytoremediation potential of multicontaminated soils. They could possibly be used with success in marginally polluted soils where their growth would not be impaired and the extraction of heavy metals could be maintained at satisfying levels.

Phytoextraction of heavy metals by canola (Brassica napus) and radish (Raphanus sativus) grown on multicontaminated soil

International Nuclear Information System (INIS)

Marchiol, L.; Assolari, S.; Sacco, P.; Zerbi, G.

2004-01-01

Phytoextraction can provide an effective in situ technique for removing heavy metals from polluted soils. The experiment reported in this paper was undertaken to study the basic potential of phytoextraction of Brassica napus (canola) and Raphanus sativus (radish) grown on a multi-metal contaminated soil in the framework of a pot-experiment. Chlorophyll contents and gas exchanges were measured during the experiment; the heavy metal phytoextraction efficiency of canola and radish were also determined and the phytoextraction coefficient for each metal calculated. Data indicated that both species are moderately tolerant to heavy metals and that radish is more so than canola. These species showed relatively low phytoremediation potential of multicontaminated soils. They could possibly be used with success in marginally polluted soils where their growth would not be impaired and the extraction of heavy metals could be maintained at satisfying levels

Phytoextraction of heavy metals by canola (Brassica napus) and radish (Raphanus sativus) grown on multicontaminated soil

Energy Technology Data Exchange (ETDEWEB)

Marchiol, L.; Assolari, S.; Sacco, P.; Zerbi, G

2004-11-01

Phytoextraction can provide an effective in situ technique for removing heavy metals from polluted soils. The experiment reported in this paper was undertaken to study the basic potential of phytoextraction of Brassica napus (canola) and Raphanus sativus (radish) grown on a multi-metal contaminated soil in the framework of a pot-experiment. Chlorophyll contents and gas exchanges were measured during the experiment; the heavy metal phytoextraction efficiency of canola and radish were also determined and the phytoextraction coefficient for each metal calculated. Data indicated that both species are moderately tolerant to heavy metals and that radish is more so than canola. These species showed relatively low phytoremediation potential of multicontaminated soils. They could possibly be used with success in marginally polluted soils where their growth would not be impaired and the extraction of heavy metals could be maintained at satisfying levels.

Repeated phytoextraction of four metal-contaminated soils using the cadmium/zinc hyperaccumulator Sedum plumbizincicola

International Nuclear Information System (INIS)

Li, Zhu; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Zhang, Hao; Christie, Peter

2014-01-01

A cadmium/zinc hyperaccumulator extracted metals from four contaminated soils over three years in a glasshouse experiment. Changes in plant metal uptake and soil total (aqua regia-extractable) and available metals were investigated. Plant Cd concentrations in a high-Cd acid soil and plant Zn concentrations in two acid soils decreased during repeated phytoextraction and were predicted by soil available metal concentrations. However, on repeated phytoextraction, plant Cd concentrations remained constant in lightly Cd-polluted acid soils, as did plant Cd and Zn in alkaline soils, although soil available metal concentrations decreased markedly. After phytoextraction acid soils showed much higher total metal removal efficiencies, indicating possible suitability of phytoextraction for acid soils. However, DGT-testing, which takes soil metal re-supply into consideration, showed substantial removal of available metal and distinct decreases in metal supply capacity in alkaline soils after phytoextraction, suggesting that a strategy based on lowering the bioavailable contaminant might be feasible. - Highlights: • Plant shoot Cd decreased in high-Cd acid soil and also plant Zn did in two acid soils. • Plant shoot Cd remained constant in low-Cd acid soil and also plant Zn did in alkaline soils. • Acidic soils showed much higher total metal removal efficiency than the alkaline soils. - Acid soil has high total metal phytoremediation efficiency while a strategy based on stripping of the bioavailable contaminant might be feasible for alkaline soil phytoremediation

In situ phytoremediation of arsenic- and metal-polluted pyrite waste with field crops: effects of soil management.

Science.gov (United States)

Vamerali, Teofilo; Bandiera, Marianna; Mosca, Giuliano

2011-05-01

Sunflower, alfalfa, fodder radish and Italian ryegrass were cultivated in severely As-Cd-Co-Cu-Pb-Zn-contaminated pyrite waste discharged in the past and capped with 0.15m of unpolluted soil at Torviscosa (Italy). Plant growth and trace element uptake were compared under ploughing and subsoiling tillages (0.3m depth), the former yielding higher contamination (∼30%) in top soil. Tillage choice was not critical for phytoextraction, but subsoiling enhanced above-ground productivity, whereas ploughing increased trace element concentrations in plants. Fodder radish and sunflower had the greatest aerial biomass, and fodder radish the best trace element uptake, perhaps due to its lower root sensitivity to pollution. Above-ground removals were generally poor (maximum of 33mgm(-2) of various trace elements), with Zn (62%) and Cu (18%) as main harvested contaminants. The most significant finding was of fine roots proliferation in shallow layers that represented a huge sink for trace element phytostabilisation. It is concluded that phytoextraction is generally far from being an efficient management option in pyrite waste. Sustainable remediation requires significant improvements of the vegetation cover to stabilise the site mechanically and chemically, and provide precise quantification of root turnover. Copyright © 2011 Elsevier Ltd. All rights reserved.

Fertilizer amendment for improving the phytoextraction of cadmium by a hyperaccumulator Rorippa globosa (Turcz.) Thell

Energy Technology Data Exchange (ETDEWEB)

Wei, Shuhe; Zhou, Qixing X. [Chinese Academy of Sciences, Shenyang (China). Key Laboratory of Pollution Ecology and Environmental Engineering; Zhu, Jiangong [Chinese Academy of Sciences, Shenyang (China). Key Laboratory of Pollution Ecology and Environmental Engineering; Chinese Academy of Sciences, Beijing (China). Graduate School; Zhan, Jie [Institute of Liaoning Basic Medicine, Shenyang (China)

2011-09-15

Purpose: Two main pathways of phytoremediation of heavy metal-contaminated soils are phytostabilization and phytoextraction. Some soil amendments can strengthen phytostabilization or phytoextraction through either reducing heavy metal bioavailability in soil or increasing the heavy metal accumulation capacity of the hyperaccumulator (enhancing heavy metal concentration or shoot biomass of the hyperaccumulator). Urea and chicken manure are often used as fertilizers. This research will explore their effects on a newly found hyperaccumulator, Rorippa globosa (Turcz.) Thell., phytoremediating cadmium (Cd). Materials and methods: Pot culture experiment was conducted to study the accumulation characteristics of R. globosa at different Cd contamination concentrations under one fertilizer level (1 g kg{sup -1} for urea and 100 g kg{sup -1} for chicken manure), as well as the same Cd dose (20 mg kg{sup -1}) under different fertilizer doses. Cd was artificially spiked at 2.5, 5, 10, and 20 mg kg{sup -1}. Urea was amended at 0.5, 1, and 2 g kg{sup -1}, while chicken manure was supplemented at 50, 100, and 200 g kg{sup -1}. The heavy metal concentration in soil and plant samples was determined using an atomic absorption spectrophotometer. pH, N, P, K, and so on in soil samples were determined by normal method. Results and discussion: The results showed that urea application did not affect the Cd concentrations in root, stem, leaf, inflorescence, and shoot of R. globosa, but chicken manure significantly decreased (p < 0.05) them by 28.4%, 29.3%, 30.8%, 24.9%, and 28.3%, respectively, owing to decreased extractable Cd in soil. Thus, strengthening the capacity (Cd accumulation in plant shoot, micrograms per pot) of urea was higher than that of chicken manure, though both shoot biomasses increased by one to threefold. Furthermore, the addition of urea and chicken manure increased the organic material, nitrogen, phosphorus and potassium, the microorganism count, urease, and the

Phytoextraction of risk elements by willow and poplar trees.

Science.gov (United States)

Kacálková, Lada; Tlustoš, Pavel; Száková, Jiřina

2015-01-01

To characterize the phytoextraction efficiency of two clones of willow trees (Salix x smithiana Willd., Salix rubens) and two clones of poplar trees (Populus nigra x maximowiczii, Populus nigra Wolterson) were planted in contaminated soil (0.4-2.0 mg Cd.kg(-1), 78-313 mg Zn.kg(-1), 21.3-118 mg Cu.kg(-1)). Field experiment was carried out in Czech Republic. The study investigated their ability to accumulate heavy metals (Cd, Zn, and Cu) in harvestable plant parts. The poplars produced higher amount of biomass than willows. Both Salix clones accumulated higher amount of Cd, Zn and Cu in their biomass (maximum 6.8 mg Cd.kg(-1), 909 mg Zn.kg(-1), and 17.7 mg Cu.kg(-1)) compared to Populus clones (maximum 2.06 mg Cd.kg(-1), 463 mg Zn.kg(-1), and 11.8 mg Cu.kg(-1)). There were no significant differences between clones of individual species. BCs for Cd and Zn were greater than 1 (the highest in willow leaves). BCs values of Cu were very low. These results indicate that Salix is more suitable plant for phytoextraction of Cd and Zn than Populus. The Cu phytoextraction potential of Salix and Populus trees was not confirmed in this experiment due to low soil availability of this element.

Potential of Taraxacum mongolicum Hand-Mazz for accelerating phytoextraction of cadmium in combination with eco-friendly amendments

Energy Technology Data Exchange (ETDEWEB)

Wei Shuhe, E-mail: shuhewei@yahoo.com.cn [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Wang Shanshan [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Zhou Qixing, E-mail: zhouqx523@yahoo.com.cn [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Zhan Jie [Department of Biotechnology, Liaoning University of Traditional Chinese Medicine, Shenyang 110101 (China); Ma Lihui [Huayou Industrial Company, Liaohe Petroleum Exploration Bureau, Panjin 124010 (China); Wu Zhijie; Sun Tieheng [Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Prasad, M.N.V. [Department of Plant Sciences, University of Hyderabad, Hyderabad 500046 (India)

2010-09-15

Phytoextraction and phytostabilization are well-established sub-processes of phytoremediation that are being followed for in situ remediation of soils contaminated with toxic metals. Taraxacum mongolicum Hand-Mazz, a newly reported Cd accumulator has shown considerable potential for phytoextracting Cd. This paper investigated the effects of urea and chicken manure on T. mongolicum phytoextracting Cd from soil using pot culture experiments. The results showed that urea application did not affect the Cd concentrations in root, leaf, inflorescence and shoot of T. mongolicum, but chicken manure significantly decreased them (p < 0.05) by 23.5%, 31.5%, 24.8% and 30.4% owing to decreased extractable Cd. Urea and chicken manure significantly increased (p < 0.05) the phytoextraction capacities ({mu}g pot{sup -1}) of T. mongolicum to Cd by 3-5-fold due to the increase in shoot biomass (increased 4-7 folds). Further, addition of urea and chicken manure increased organic matter, nitrogen, phosphorus and potassium, the microorganism count, urease and phosphatase activities of soil indicating their eco-friendly function. Urea is ideal for optimizing phytoextraction of T. mongolicum to Cd, while chicken manure is appropriate for phytostabilization.

Molasses melanoidin promotes copper uptake for radish sprouts: the potential for an accelerator of phytoextraction.

Science.gov (United States)

Hatano, Ken-Ichi; Kanazawa, Kazuki; Tomura, Hiroki; Yamatsu, Takeshi; Tsunoda, Kin-Ichi; Kubota, Kenji

2016-09-01

Phytoextraction has been proposed as an alternative remediation technology for heavy metal contamination, and it is well known that chelators may alter the toxicity of heavy metals and the bioavailability in plants. Our previous work demonstrated that an adsorbent-column chromatography can effectively separate melanoidin-like product (MLP) from sugarcane molasses. The aim of this study was to examine the chelating property of MLP and to evaluate the facilitatory influence on the phytoextraction efficiency of Japanese radish. The result showed that MLP binds to all the metal ions examined and the binding capacity of MLP toward Cu(2+) seems to be the highest among them. The metal detoxification by MLP followed the order of Pb(2+) > Zn(2+) > Ni(2+) > Cu(2+) > Fe(2+) > Cd(2+) > Co(2+). Furthermore, in the phytoextraction experiment using copper sulfate, the application of MLP accelerated the detoxification of copper and the bioavailability in radish sprouts. Thus, these results suggest that MLP possesses the potential for an accelerator of phytoextraction in the copper-contaminated media.

Field evaluation of Cd and Zn phytoextraction potential by the hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri

International Nuclear Information System (INIS)

McGrath, S.P.; Lombi, E.; Gray, C.W.; Caille, N.; Dunham, S.J.; Zhao, F.J.

2006-01-01

Field trials were undertaken to investigate the effect of the application of metal mobilizing agents, different sowing strategies and length of growing season on the extraction of Cd and Zn from soils by Thlaspi caerulescens and Arabidopsis halleri. None of the mobilizing agents used enhanced metal accumulation by T. caerulescens. Between 1998 and 2000, on average across plots where Cd or Zn exceeded allowable limits, T. caerulescens removed 1.3 and 0.3% of the total soil Cd and Zn. In one season when T. caerulescens was grown for 14 months, 21.7 and 4.4% of the total soil Cd and Zn was removed. This was larger than values found when T. caerulescens was grown for 4 months. A. halleri accumulated similar concentrations of Zn, but lower Cd concentrations than T. caerulescens. The results indicate that metal phytoextraction using T. caerulescens can be used to clean up soils moderately contaminated by Cd. - The hyperaccumulator Thlaspi caerulescens (the Ganges ecotype) is more efficient at phytoextracting Cd than Zn from contaminated soil

Use of Energy Crop (Ricinus communis L.) for Phytoextraction of Heavy Metals Assisted with Citric Acid.

Science.gov (United States)

Zhang, Hui; Chen, Xueping; He, Chiquan; Liang, Xia; Oh, Kokyo; Liu, Xiaoyan; Lei, Yanru

2015-01-01

Ricinus communis L. is a bioenergetic crop with high-biomass production and tolerance to cadmium (Cd) and lead (Pb), thus, the plant is a candidate crop for phytoremediation. Pot experiments were performed to study the effects of citric acid in enhancing phytoextraction of Cd/Pb by Ricinus communis L. Citric acid increased Cd and Pb contents in plant shoots in all treatments by about 78% and 18-45%, respectively, at the dosage of 10 mM kg(-1) soil without affecting aboveground biomass production. Addition of citric acid reduced CEC, weakened soil adsorption of heavy metals and activated Cd and Pb in soil solutions. The acid-exchangeable fraction (BCR-1) of Pb remained lower than 7% and significantly increased with citric acid amendment. Respective increases in soil evaluation index induces by 14% and 19% under the Cd1Pb50 and Cd1Pb250 treatments upon addition of citric acid resulted in soil quality improvement. Ricinus communis L. has great potential in citric acid-assisted phytoextraction for Cd and Pb remediation.

Field evaluation of Cd and Zn phytoextraction potential by the hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri

Energy Technology Data Exchange (ETDEWEB)

McGrath, S.P. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom)]. E-mail: steve.mcgrath@bbsrc.ac.uk; Lombi, E. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Gray, C.W. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Caille, N. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Dunham, S.J. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Zhao, F.J. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom)

2006-05-15

Field trials were undertaken to investigate the effect of the application of metal mobilizing agents, different sowing strategies and length of growing season on the extraction of Cd and Zn from soils by Thlaspi caerulescens and Arabidopsis halleri. None of the mobilizing agents used enhanced metal accumulation by T. caerulescens. Between 1998 and 2000, on average across plots where Cd or Zn exceeded allowable limits, T. caerulescens removed 1.3 and 0.3% of the total soil Cd and Zn. In one season when T. caerulescens was grown for 14 months, 21.7 and 4.4% of the total soil Cd and Zn was removed. This was larger than values found when T. caerulescens was grown for 4 months. A. halleri accumulated similar concentrations of Zn, but lower Cd concentrations than T. caerulescens. The results indicate that metal phytoextraction using T. caerulescens can be used to clean up soils moderately contaminated by Cd. - The hyperaccumulator Thlaspi caerulescens (the Ganges ecotype) is more efficient at phytoextracting Cd than Zn from contaminated soil.

Photosynthetic pigments and peroxidase activity of Lepidium sativum L. during assisted Hg phytoextraction.

Science.gov (United States)

Smolinska, Beata; Leszczynska, Joanna

2017-05-01

The study was conducted to evaluate metabolic answer of Lepidium sativum L. on Hg, compost, and citric acid during assisted phytoextraction. The chlorophyll a and b contents, total carotenoids, and activity of peroxidase were determined in plants exposed to Hg and soil amendments. Hg accumulation in plant shoots was also investigated. The pot experiments were provided in soil artificially contaminated by Hg and/or supplemented with compost and citric acid. Hg concentration in plant shoots and soil substrates was determined by cold vapor atomic absorption spectroscopy (CV-AAS) method after acid mineralization. The plant photosynthetic pigments and peroxidase activity were measured by standard spectrophotometric methods. The study shows that L. sativum L. accumulated Hg in its aerial tissues. An increase in Hg accumulation was noticed when soil was supplemented with compost and citric acid. Increasing Hg concentration in plant shoots was correlated with enhanced activation of peroxidase activity and changes in total carotenoid concentration. Combined use of compost and citric acid also decreased the chlorophyll a and b contents in plant leaves. Presented study reveals that L. sativum L. is capable of tolerating Hg and its use during phytoextraction assisted by combined use of compost and citric acid lead to decreasing soil contamination by Hg.

Cadmium phytoextraction potential of different Alyssum species

International Nuclear Information System (INIS)

Barzanti, R.; Colzi, I.; Arnetoli, M.; Gallo, A.; Pignattelli, S.; Gabbrielli, R.; Gonnelli, C.

2011-01-01

Highlights: ► The possibility of using serpentine plants for phytoextraction of Cd was investigated. ► Variation in Cd tolerance, accumulation and translocation in three Alyssum plants with different phenotypes were found. ► Alyssum montanum showed higher Cd tolerance and accumulation than the Ni hyperaccumulator Alyssum bertolonii. ► As for the kinetic parameters of the Cd uptake system, A. montanum presented a low apparent K m value. ► The V max values were not significantly different among the plants. - Abstract: This work was planned for providing useful information about the possibility of using serpentine adapted plants for phytoextraction of cadmium, element scarcely represented in such metalliferous environment. To this aim, we investigated variation in cadmium tolerance, accumulation and translocation in three Alyssum plants with different phenotypes: Alyssum bertolonii, that is a serpentine endemic nickel hyperaccumulator, and two populations of Alyssum montanum, one adapted and one not adapted to serpentine soils. Plants were hydroponically cultivated in presence of increasing concentrations of CdSO 4 for two weeks. For the metal concentration used in the experiments, the three different Alyssum populations showed variation in cadmium tolerance, accumulation and content. The serpentine adapted population of A. montanum showed statistically higher cadmium tolerance and accumulation than A. bertolonii and the population of A. montanum not adapted to serpentine soil thus deserving to be investigated for phytoextraction purposes. Furthermore, as for the kinetic parameters of the cadmium uptake system, A. montanum serpentine population presented a low apparent K m value, suggesting a high affinity for this metal of its uptake system, whereas the V max values were not significantly different among the plants. Present data revealed metallicolous plants are also suitable for the phytoremediation of metals underrepresented in the environment of their

Chelator induced phytoextraction and in situ soil washing of Cu

International Nuclear Information System (INIS)

Kos, Bostjan; Lestan, Domen

2004-01-01

In a soil column experiment, we investigated the effect of 5 mmol kg -1 soil addition of citric acid, ethylenediamine tetraacetate (EDTA), diethylenetriamine-pentaacetate (DTPA) and [S,S]-stereoisomer of ethylenediamine-disuccinate (EDDS) on phytoextraction of Cu from a vineyard soil with 162.6 mg kg -1 Cu, into the test plant Brassica rapa var. pekinensis. We also examined the use of a horizontal permeable barrier, composed of layers of nutrient enriched sawdust and apatite, for reduction of chelator induced Cu leaching. The addition of all chelators, except citric acid, enhanced Cu mobility and caused leaching of 19.5-23% of initial total Cu from the soil column. However, Cu plant uptake did not increase accordingly; the most effective was the EDDS treatment, in which plant Cu concentration reached 37.8±1.3 mg kg -1 Cu and increased by 3.3-times over the control treatment. The addition of none of the chelators in the concentration range from 5 to 15 mmol kg -1 exerted any toxic effect on respiratory soil microorganisms. When EDDS was applied into the columns with horizontal permeable barriers, only 0.53±0.32% of the initial total Cu was leached. Cu (36.7%) was washed from the 18 cm soil layer above the barrier and accumulated in the barrier. Our results indicate that rather than for a reduction of Cu leaching during rather ineffective chelate induced Cu phytoextraction, horizontal permeable barriers could be more effective in a new remediation technique of controlled in situ soil washing of Cu with biodegradable chelates

Effects of phytoextraction on heavy metal concentrations and pH of pore-water of biosolids determined using an in situ sampling technique

Energy Technology Data Exchange (ETDEWEB)

Huynh, T.T. [Applied Ecology Research Group, School of Botany, University of Melbourne, Parkville, VIC 3010 (Australia)], E-mail: t.huynh11@pgrad.unimelb.edu.au; Laidlaw, W.S. [Applied Ecology Research Group, School of Botany, University of Melbourne, Parkville, VIC 3010 (Australia); Singh, B. [Faculty of Agriculture, Food and Natural Resources, University of Sydney, Sydney, NSW 2006 (Australia); Gregory, D. [Research and Technology Division, Melbourne Water, Melbourne, VIC 3001 (Australia); Baker, A.J.M. [Applied Ecology Research Group, School of Botany, University of Melbourne, Parkville, VIC 3010 (Australia)

2008-12-15

Heavy metal concentrations and pH of pore-water in contaminated substrates are important factors in controlling metal uptake by plants. We investigated the effects of phytoextraction on these properties in the solution phase of biosolids and diluted biosolids in a 12-month phytoextraction column experiment. Phytoextraction using Salix and Populus spp. temporarily decreased pore-water pH of the substrates over the experimental period followed by a return to initial pH conditions. Salix x reichardtii and Populus balsamifera effectively extracted Ni, Zn and Cd and actively mobilized these metals from the solid to the solution phase. S. x reichardtii had the stronger effect on mobilization of metals due to its larger root system. Phytoextraction did not affect Cu in the solution phase of the biosolids. Heavy metals were leached down to lower depths of the columns during the phytoextraction process. - Salix x reichardtii and Populus balsamifera extracted Ni, Zn and Cd and mobilized these metals in biosolids during phytoextraction.

Effects of phytoextraction on heavy metal concentrations and pH of pore-water of biosolids determined using an in situ sampling technique

International Nuclear Information System (INIS)

Huynh, T.T.; Laidlaw, W.S.; Singh, B.; Gregory, D.; Baker, A.J.M.

2008-01-01

Heavy metal concentrations and pH of pore-water in contaminated substrates are important factors in controlling metal uptake by plants. We investigated the effects of phytoextraction on these properties in the solution phase of biosolids and diluted biosolids in a 12-month phytoextraction column experiment. Phytoextraction using Salix and Populus spp. temporarily decreased pore-water pH of the substrates over the experimental period followed by a return to initial pH conditions. Salix x reichardtii and Populus balsamifera effectively extracted Ni, Zn and Cd and actively mobilized these metals from the solid to the solution phase. S. x reichardtii had the stronger effect on mobilization of metals due to its larger root system. Phytoextraction did not affect Cu in the solution phase of the biosolids. Heavy metals were leached down to lower depths of the columns during the phytoextraction process. - Salix x reichardtii and Populus balsamifera extracted Ni, Zn and Cd and mobilized these metals in biosolids during phytoextraction

[Enhanced phytoextraction of heavy metal contaminated soil by chelating agents and auxin indole-3-acetic acid].

Science.gov (United States)

Zhou, Jian-min; Dang, Zhi; Chen, Neng-chang; Xu, Sheng-guang; Xie, Zhi-yi

2007-09-01

The environmental risk of chelating agents such as EDTA application to the heavy metals polluted soils and the stress on plant roots due to the abrupt increase metals concentration limit the wide commercial use of chelate-induced phytoextraction. Chelating agent ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) and auxin indole-3-acetic acid (IAA) were used for enhancing heavy metals uptake from soils by Zea mays L. (corn) in pot experiments. The metals content in plant tissues was quantified using an inductively coupled plasma mass spectrometer (ICP-MS). The results showed that the combination of IAA and EDTA increased the biomass by about 40.0% and the contents of Cu, Zn, Cd and Pb in corn shoots by 27.0%, 26.8%, 27.5% and 32.8% respectively, as compared to those in EDTA treatment. While NTA&IAA treatment increased the biomass by about 29.9% and the contents of Cu, Zn, Cd and Pb in corn shoots by 31.8%, 27.6%, 17.0% and 26.9% respectively, as compared to those in NTA treatment. These results indicated that corn growth was promoted, and the biomass and the accumulation of heavy metals in plant shoots were increased significantly with the addition of IAA, which probably helps to change the cell membrane properties and the biomass distribution, resulting in the alleviation of the phytotoxicity of metals and the chelating agents.

Phytoextraction of heavy metals from municipal sewage sludge by Rosa multiflora and Sida hermaphrodita.

Science.gov (United States)

Antonkiewicz, Jacek; Kołodziej, Barbara; Bielińska, Elżbieta Jolanta

2017-04-03

The aim of the study was to evaluate the efficacy of the multiflora rose var. "Jatar" (Rosa multiflora Thunb. ex Murray) and the Virginia fanpetals (Sida hermaphrodita Rusby) to phytoextract heavy metals from municipal sewage sludge. The 6-year field experiment involved four levels of fertilization with sewage sludge at doses of 0, 10, 20, 40, and 60 Mg DM (Dry Mass) sludge ha -1 . The increasing doses of sewage sludge were found to significantly increase the yield of multiflora rose and Virginia fanpetals biomass. They also significantly increased the content of heavy metals in these plants. The highest uptake of heavy metals by the multiflora rose and Virginia fanpetals crops was recorded at the fertilization dose of 60 Mg DM ⋅ ha -1 . Our investigations show that the Virginia fanpetals was more efficient in the phytoextraction of Cr, Ni, Cu, Zn, and Cd from the sewage sludge than the multiflora rose, due to the greater yields and higher heavy metal uptake by the former plant. In turn, the multiflora rose phytoextracted greater amounts of Pb from the sewage sludge. The analyses indicate that the Virginia fanpetals can be used for phytoremediation (phytoextraction) of heavy metals contained in sewage sludge.

Model evaluation of the phytoextraction potential of heavy metal hyperaccumulators and non-hyperaccumulators

Energy Technology Data Exchange (ETDEWEB)

Liang, H.-M. [Agricultural Biotechnology Research Center, Academia Sinica, 128 Section 2, Academia Road, Taipei, Taiwan 11529, Taiwan (China); Lin, T.-H. [Department of Statistics, National Taipei University, Taiwan (China); Chiou, J.-M. [Institute of Statistical Science, Academia Sinica, Taiwan (China); Yeh, K.-C., E-mail: kcyeh@gate.sinica.edu.t [Agricultural Biotechnology Research Center, Academia Sinica, 128 Section 2, Academia Road, Taipei, Taiwan 11529, Taiwan (China)

2009-06-15

Evaluation of the remediation ability of zinc/cadmium in hyper- and non-hyperaccumulator plant species through greenhouse studies is limited. To bridge the gap between greenhouse studies and field applications for phytoextraction, we used published data to examine the partitioning of heavy metals between plants and soil (defined as the bioconcentration factor). We compared the remediation ability of the Zn/Cd hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri and the non-hyperaccumulators Nicotiana tabacum and Brassica juncea using a hierarchical linear model (HLM). A recursive algorithm was then used to evaluate how many harvest cycles were required to clean a contaminated site to meet Taiwan Environmental Protection Agency regulations. Despite the high bioconcentration factor of both hyperaccumulators, metal removal was still limited because of the plants' small biomass. Simulation with N. tabacum and the Cadmium model suggests further study and development of plants with high biomass and improved phytoextraction potential for use in environmental cleanup. - A quantitative solution enables the evaluation of Zn/Cd phytoextraction.

Model evaluation of the phytoextraction potential of heavy metal hyperaccumulators and non-hyperaccumulators

International Nuclear Information System (INIS)

Liang, H.-M.; Lin, T.-H.; Chiou, J.-M.; Yeh, K.-C.

2009-01-01

Evaluation of the remediation ability of zinc/cadmium in hyper- and non-hyperaccumulator plant species through greenhouse studies is limited. To bridge the gap between greenhouse studies and field applications for phytoextraction, we used published data to examine the partitioning of heavy metals between plants and soil (defined as the bioconcentration factor). We compared the remediation ability of the Zn/Cd hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri and the non-hyperaccumulators Nicotiana tabacum and Brassica juncea using a hierarchical linear model (HLM). A recursive algorithm was then used to evaluate how many harvest cycles were required to clean a contaminated site to meet Taiwan Environmental Protection Agency regulations. Despite the high bioconcentration factor of both hyperaccumulators, metal removal was still limited because of the plants' small biomass. Simulation with N. tabacum and the Cadmium model suggests further study and development of plants with high biomass and improved phytoextraction potential for use in environmental cleanup. - A quantitative solution enables the evaluation of Zn/Cd phytoextraction.

Potential of Taraxacum mongolicum Hand-Mazz for accelerating phytoextraction of cadmium in combination with eco-friendly amendments

International Nuclear Information System (INIS)

Wei Shuhe; Wang Shanshan; Zhou Qixing; Zhan Jie; Ma Lihui; Wu Zhijie; Sun Tieheng; Prasad, M.N.V.

2010-01-01

Phytoextraction and phytostabilization are well-established sub-processes of phytoremediation that are being followed for in situ remediation of soils contaminated with toxic metals. Taraxacum mongolicum Hand-Mazz, a newly reported Cd accumulator has shown considerable potential for phytoextracting Cd. This paper investigated the effects of urea and chicken manure on T. mongolicum phytoextracting Cd from soil using pot culture experiments. The results showed that urea application did not affect the Cd concentrations in root, leaf, inflorescence and shoot of T. mongolicum, but chicken manure significantly decreased them (p -1 ) of T. mongolicum to Cd by 3-5-fold due to the increase in shoot biomass (increased 4-7 folds). Further, addition of urea and chicken manure increased organic matter, nitrogen, phosphorus and potassium, the microorganism count, urease and phosphatase activities of soil indicating their eco-friendly function. Urea is ideal for optimizing phytoextraction of T. mongolicum to Cd, while chicken manure is appropriate for phytostabilization.

Nodulation by Sinorhizobium meliloti originated from a mining soil alleviates Cd toxicity and increases Cd-phytoextraction in Medicago sativa L.

Science.gov (United States)

Ghnaya, Tahar; Mnassri, Majda; Ghabriche, Rim; Wali, Mariem; Poschenrieder, Charlotte; Lutts, Stanley; Abdelly, Chedly

2015-01-01

Besides their role in nitrogen supply to the host plants as a result of symbiotic N fixation, the association between legumes and Rhizobium could be useful for the rehabilitation of metal-contaminated soils by phytoextraction. A major limitation presents the metal-sensitivity of the bacterial strains. The aim of this work was to explore the usefulness of Sinorhizobium meliloti originated from a mining site for Cd phytoextraction by Medicago sativa. Inoculated and non-inoculated plants were cultivated for 60 d on soils containing 50 and/or 100 mg Cd kg(-1) soil. The inoculation hindered the occurrence of Cd- induced toxicity symptoms that appeared in the shoots of non-inoculated plants. This positive effect of S. meliloti colonization was accompanied by an increase in biomass production and improved nutrient acquisition comparatively to non-inoculated plants. Nodulation enhanced Cd absorption by the roots and Cd translocation to the shoots. The increase of plant biomass concomitantly with the increase of Cd shoot concentration in inoculated plants led to higher potential of Cd-phytoextraction in these plants. In the presence of 50 mg Cd kg(-1) in the soil, the amounts of Cd extracted in the shoots were 58 and 178 μg plant(-1) in non-inoculated and inoculated plants, respectively. This study demonstrates that this association M. sativa-S. meliloti may be an efficient biological system to extract Cd from contaminated soils.

Changes in metal availability, desorption kinetics and speciation in contaminated soils during repeated phytoextraction with the Zn/Cd hyperaccumulator Sedum plumbizincicola

International Nuclear Information System (INIS)

Li, Zhu; Jia, Mingyun; Wu, Longhua; Christie, Peter; Luo, Yongming

2016-01-01

Phytoextraction is one of the most promising technologies for the remediation of metal contaminated soils. Changes in soil metal availability during phytoremediation have direct effects on removal efficiency and can also illustrate the interactive mechanisms between hyperaccumulators and metal contaminated soils. In the present study the changes in metal availability, desorption kinetics and speciation in four metal-contaminated soils during repeated phytoextraction by the zinc/cadmium hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) over three years were investigated by chemical extraction and the DGT-induced fluxes in soils (DIFS) model. The available metal fractions (i.e. metal in the soil solution extracted by CaCl_2 and by EDTA) decreased greatly by >84% after phytoextraction in acid soils and the deceases were dramatic at the initial stages of phytoextraction. However, the decreases in metal extractable by CaCl_2 and EDTA in calcareous soils were not significant or quite low. Large decreases in metal desorption rate constants evaluated by DIFS were found in calcareous soils. Sequential extraction indicated that the acid-soluble metal fraction was easily removed by S. plumbizincicola from acid soils but not from calcareous soils. Reducible and oxidisable metal fractions showed discernible decreases in acid and calcareous soils, indicating that S. plumbizincicola can mobilize non-labile metal for uptake but the residual metal cannot be removed. The results indicate that phytoextraction significantly decreases metal availability by reducing metal pool sizes and/or desorption rates and that S. plumbizincicola plays an important role in the mobilization of less active metal fractions during repeated phytoextraction. - Highlights: • Metal availability, desorption, and speciation were tested during phytoextraction. • Metal availability showed an initial sharp decline then a slight change in acid soils. • Metal availability changed little during

Effect of edta on arsenic phytoextraction by arundo donax

International Nuclear Information System (INIS)

Mirza, N.; Pervez, A.; Mahmood, Q.; Shah, M.M.; Farooq, U.

2014-01-01

Ligand assisted metal uptake by plants is recent trend in environmental clean-up. Arundo donax L. has been demonstrated as a suitable bioresource for the phytoextraction of arsenic recently. A. donax L. plants were grown in arsenic contaminated soil with doses (5 and 10 mg kg/sup -1/) of Ethylene Diamine Tetra Acetic Acid (EDTA) to investigate chelator-assisted phytoextraction. The arsenic treatments included control (no metal) and five doses of arsenic, i.e., 50, 100, 300, 600 and 1000 micro g kg/sup -1/ . The arsenic concentrations linearly increased in parts of plant with the increasing arsenic and EDTA in growth medium. Ligand addition also resulted in the increased arsenic accumulation in the shoot over its control plants. EDTA additionat the rate 5 mg kg/sup -1/ to the treatment system may effectively increase the arsenic uptake by A. donax without severe growth suppression. (author)

Effects of phytoextraction on heavy metal concentrations and pH of pore-water of biosolids determined using an in situ sampling technique.

Science.gov (United States)

Huynh, T T; Laidlaw, W S; Singh, B; Gregory, D; Baker, A J M

2008-12-01

Heavy metal concentrations and pH of pore-water in contaminated substrates are important factors in controlling metal uptake by plants. We investigated the effects of phytoextraction on these properties in the solution phase of biosolids and diluted biosolids in a 12-month phytoextraction column experiment. Phytoextraction using Salix and Populus spp. temporarily decreased pore-water pH of the substrates over the experimental period followed by a return to initial pH conditions. Salixxreichardtii and Populus balsamifera effectively extracted Ni, Zn and Cd and actively mobilized these metals from the solid to the solution phase. S.xreichardtii had the stronger effect on mobilization of metals due to its larger root system. Phytoextraction did not affect Cu in the solution phase of the biosolids. Heavy metals were leached down to lower depths of the columns during the phytoextraction process.

Trace element phytoextraction from contaminated soil: a case study under Mediterranean climate.

Science.gov (United States)

Guidi Nissim, Werther; Palm, Emily; Mancuso, Stefano; Azzarello, Elisa

2018-03-01

The current field study aims to assess the suitability of four different plant species (i.e. poplar, willow, hemp and alfalfa) to be used for trace element (TE) (i.e. Cd, Cu, Ni, Pb and Zn) phytoextraction under hot-arid Mediterranean climate conditions. Plants were grown for two consecutive years on a moderate TE contaminated soil, supplied with water and mineral nutrients. The growth and physiological parameters were assessed throughout the trial to compare the response of plants to the environmental pollution, and TE uptake rates were measured for aboveground plant tissues. The phytoextraction rate for each species was expressed as a function of aboveground biomass yield and the TE uptake and translocation within the plant. Alfalfa played a significant role in reducing extractable Ni (60.6%) and Zn (46%) in the soil, whereas hemp reduced 32% of extractable Cd and 46% of extractable Pb; poplar decreased extractable Cd (37%), Ni (49%), Pb (46%) and Zn (63%); and willow reduced the extractable Zn (73%) compared to the beginning of the trial. No change in total TE content was observed; however, poplar and willow were able to extract and accumulate the highest amount of Zn (3200 and 5200 g ha -1  year -1 respectively) and Cu (182 and 116 g ha -1  year -1 ), whereas hemp, with 36 g ha -1  year -1 , showed the best phytoextraction potential for Pb. Overall, we found a positive correlation between the phytoextraction rate and biomass yield, extractable TE concentration and translocation factor (TF) and a negative relationship with Ca concentration in the soil.

Cadmium phytoextraction potential of different Alyssum species

Energy Technology Data Exchange (ETDEWEB)

Barzanti, R., E-mail: rbarzanti@supereva.it [Department of Evolutionary Biology, Universita di Firenze, via Micheli 1, 50121 Firenze (Italy); Colzi, I., E-mail: ilariacolzi@hotmail.it [Department of Evolutionary Biology, Universita di Firenze, via Micheli 1, 50121 Firenze (Italy); Arnetoli, M., E-mail: miluscia@gmail.com [Department of Evolutionary Biology, Universita di Firenze, via Micheli 1, 50121 Firenze (Italy); Gallo, A., E-mail: galloalessia@hotmail.com [Department of Evolutionary Biology, Universita di Firenze, via Micheli 1, 50121 Firenze (Italy); Pignattelli, S., E-mail: sara.pignattelli@gmail.com [Department of Evolutionary Biology, Universita di Firenze, via Micheli 1, 50121 Firenze (Italy); Gabbrielli, R., E-mail: gabbrielli@unifi.it [Department of Evolutionary Biology, Universita di Firenze, via Micheli 1, 50121 Firenze (Italy); Gonnelli, C., E-mail: cristina.gonnelli@unifi.it [Department of Evolutionary Biology, Universita di Firenze, via Micheli 1, 50121 Firenze (Italy)

2011-11-30

Highlights: Black-Right-Pointing-Pointer The possibility of using serpentine plants for phytoextraction of Cd was investigated. Black-Right-Pointing-Pointer Variation in Cd tolerance, accumulation and translocation in three Alyssum plants with different phenotypes were found. Black-Right-Pointing-Pointer Alyssum montanum showed higher Cd tolerance and accumulation than the Ni hyperaccumulator Alyssum bertolonii. Black-Right-Pointing-Pointer As for the kinetic parameters of the Cd uptake system, A. montanum presented a low apparent K{sub m} value. Black-Right-Pointing-Pointer The V{sub max} values were not significantly different among the plants. - Abstract: This work was planned for providing useful information about the possibility of using serpentine adapted plants for phytoextraction of cadmium, element scarcely represented in such metalliferous environment. To this aim, we investigated variation in cadmium tolerance, accumulation and translocation in three Alyssum plants with different phenotypes: Alyssum bertolonii, that is a serpentine endemic nickel hyperaccumulator, and two populations of Alyssum montanum, one adapted and one not adapted to serpentine soils. Plants were hydroponically cultivated in presence of increasing concentrations of CdSO{sub 4} for two weeks. For the metal concentration used in the experiments, the three different Alyssum populations showed variation in cadmium tolerance, accumulation and content. The serpentine adapted population of A. montanum showed statistically higher cadmium tolerance and accumulation than A. bertolonii and the population of A. montanum not adapted to serpentine soil thus deserving to be investigated for phytoextraction purposes. Furthermore, as for the kinetic parameters of the cadmium uptake system, A. montanum serpentine population presented a low apparent K{sub m} value, suggesting a high affinity for this metal of its uptake system, whereas the V{sub max} values were not significantly different among the

Naturally-assisted metal phytoextraction by Brassica carinata: Role ofroot exudates

Energy Technology Data Exchange (ETDEWEB)

Quartacci, Mike F., E-mail: mfquart@agr.unipi.i [Dipartimento di Chimica e Biotecnologie Agrarie, Universita di Pisa, Via del Borghetto 80, 56124 Pisa (Italy); Irtelli, Barbara [Dipartimento di Chimica e Biotecnologie Agrarie, Universita di Pisa, Via del Borghetto 80, 56124 Pisa (Italy); Gonnelli, Cristina; Gabbrielli, Roberto [Dipartimento di Biologia Vegetale, Sezione di Ecologia e Fisiologia Vegetale, Universita di Firenze, Via Micheli 1, 50121 Firenze (Italy); Navari-Izzo, Flavia [Dipartimento di Chimica e Biotecnologie Agrarie, Universita di Pisa, Via del Borghetto 80, 56124 Pisa (Italy)

2009-10-15

Due to relatively high chelant dosages and potential environmental risks it is necessary to explore different approaches in the remediation of metal-contaminated soils. The present study focussed on the removal of metals (As, Cd, Cu, Pb and Zn) from a multiple metal-contaminated soil by growing Brassica carinata plants in succession to spontaneous metallicolous populations of Pinus pinaster, Plantago lanceolata and Silene paradoxa. The results showed that the growth of the metallicolous populations increased the extractable metal levels in the soil, which resulted in a higher accumulation of metals in the above-ground parts of B. carinata. Root exudates of the three metallicolous species were analysed to elucidate their possible role in the enhanced metal availability. The presence of metals stimulated the exudation of organic and phenolic acids as well as flavonoids. It was suggested that root exudates played an important role in solubilising metals in soil and in favouring their uptake by roots. - Phytoextraction of metals is enhanced in Brassica carinata grown in succession to metallicolous populations of spontaneous species.

Naturally-assisted metal phytoextraction by Brassica carinata: Role ofroot exudates

International Nuclear Information System (INIS)

Quartacci, Mike F.; Irtelli, Barbara; Gonnelli, Cristina; Gabbrielli, Roberto; Navari-Izzo, Flavia

2009-01-01

Due to relatively high chelant dosages and potential environmental risks it is necessary to explore different approaches in the remediation of metal-contaminated soils. The present study focussed on the removal of metals (As, Cd, Cu, Pb and Zn) from a multiple metal-contaminated soil by growing Brassica carinata plants in succession to spontaneous metallicolous populations of Pinus pinaster, Plantago lanceolata and Silene paradoxa. The results showed that the growth of the metallicolous populations increased the extractable metal levels in the soil, which resulted in a higher accumulation of metals in the above-ground parts of B. carinata. Root exudates of the three metallicolous species were analysed to elucidate their possible role in the enhanced metal availability. The presence of metals stimulated the exudation of organic and phenolic acids as well as flavonoids. It was suggested that root exudates played an important role in solubilising metals in soil and in favouring their uptake by roots. - Phytoextraction of metals is enhanced in Brassica carinata grown in succession to metallicolous populations of spontaneous species.

Phytoextraction of Pb and Cu contaminated soil with maize and microencapsulated EDTA.

Science.gov (United States)

Xie, Zhiyi; Wu, Longhua; Chen, Nengchang; Liu, Chengshuai; Zheng, Yuji; Xu, Shengguang; Li, Fangbai; Xu, Yanling

2012-09-01

Chelate-assisted phytoextraction using agricultural crops has been widely investigated as a remediation technique for soils contaminated with low mobility potentially toxic elements. Here, we report the use of a controlled-release microencapsulated EDTA (Cap-EDTA) by emulsion solvent evaporation to phytoremediate soil contaminated with Pb and Cu. Incubation experiments were carried out to assess the effect of Cap- and non-microencapsulated EDTA (Ncap-EDTA) on the mobility of soil metals. Results showed EDTA effectively increased the mobility of Pb and Cu in the soil solution and Cap-EDTA application provided lower and more constant water-soluble concentrations of Pb and Cu in comparison with. Phytotoxicity may be alleviated and plant uptake of Pb and Cu may be increased after the incorporation of Cap-EDTA. In addition phytoextraction efficiencies of maize after Cap- and Ncap-EDTA application were tested in a pot experiment. Maize shoot concentrations of Pb and Cu were lower with Cap-EDTA application than with Ncap-EDTA. However, shoot dry weight was significantly higher with Cap-EDTA application. Consequently, the Pb and Cu phytoextraction potential of maize significantly increased with Cap-EDTA application compared with the control and Ncap-EDTA application.

Agronomy towards the Green Economy. Optimization of metal phytoextraction

Directory of Open Access Journals (Sweden)

Luca Marchiol

2011-09-01

Full Text Available Traditional techniques for remediation of polluted soils are based on a physical-chemical approach; such techniques are expensive, have adverse effects on soil quality and are often highly expensive. In the scenario of the Green Economy, low cost and impact technologies should be promoted. Phytotechnologies are remediation technologies that use plants for the containment, degradation or removal of contaminants from polluted matrices for the restoration of degraded ecosystems. The process of phytoextraction is substantially based on plant-soil interactions that involves the mass transfer of an inorganic pollutant from the bulk soil to the plant biomass. This implies that the management of the two elements of the system (plant and soil should have effects on the efficiency of the process. As phytoremediation is essentially an agronomic approach, its success depends ultimately on standard agronomic practices. The present paper aims give an overview on the role of agronomy in the optimization of metal phytoextraction is focused.

Phytoextraction trials of cadmium and lead contaminated soil using ...

African Journals Online (AJOL)

Study on the phytoextraction of cadmium (Cd) and lead (Pb) artificially contaminated soil using 3 weed species (Ageratum conyzoides, Syndrella nodiflora and Cleome rutidosperma) was carried out at the Centre for Ecological Studies, University of Port Harcourt. A Randomized Complete Block Design consisting of 2 sets of ...

ROLE OF SOME CHEMICAL MATERIALS ON THE PHYTO-EXTRACTION OF HEAVY METALS FROM CONTAMINATED SOILS WITH SUNFLOWER PLANTS (HELIANTHUS ANNUUS)

International Nuclear Information System (INIS)

ABD EL-BARY, S.A.; EL-NAKA, E.A.; RIZK, M.A.; LOTFY, S.M.

2009-01-01

Chelation and complexation of heavy metals were evaluated as practical ways to solubilize, detoxify and enhance heavy metals accumulation by plants. Sunflower (Helianthus annuus) was selected as potential heavy metals accumulator for metals phyto-extraction in two selected soils (clayey and sandy). To enhance metals phyto-extraction, ammonium nitrate and organic chelates such as EDTA and citric acid were added to soils at the rates from 0 to 20 mmol/kg soil as extracting solutions and applied to the soil by mixing thoroughly before planting. Dry matter production and metals concentrations in shoots and roots and soil pH were measured after 60 days.Plant dry matter production and metals accumulation were varied with soil contamination, chelate / organic acid form and rate, and soil type. The highest metals concentration was obtained in plants grown on clayey soil, however, the lowest content was observed in case of sandy soil. Addition of citric acid increased metals accumulation and translocation to the shoots significantly. Addition of 20 mmol/kg of citric acid to clayey soils increased metals concentration in shoots several folds of magnitude, but addition of ammonium nitrate had little effect on metal translocation to shoots. Citric acid was the most effective chelate in plant accumulation of tested metals.

Phytoextraction with Salix viminalis in a moderately to strongly contaminated area.

Science.gov (United States)

Tőzsér, Dávid; Harangi, Sándor; Baranyai, Edina; Lakatos, Gyula; Fülöp, Zoltán; Tóthmérész, Béla; Simon, Edina

2018-02-01

We tested the suitability of Salix viminalis for phytoextraction with the analysis of selected elements in soil, root, and leaf, and by visual tree condition assessment in an area with varying levels of contamination. Bioconcentration factor (BCF) and translocation factor (TF) were used to assess the phytoextraction potential of willows. The middle part of the study area was strongly contaminated, while the northern and southern parts were moderately contaminated. We found increasing element concentrations toward deeper layers. Mean concentrations of elements in roots were similar among the three parts, while in leaves the highest concentrations were found in the strongly contaminated part of the study area. Tree condition scores were the lowest in the strongly contaminated part of the study area, which was caused by Al, Ca, K, Mg, Ni, Sr, and Zn concentration. These elements induced leaf disease and leaf feeders. The highest BCF values were found for Cu, Fe, Mn, and Zn in root, and for Cd and Zn in leaves, indicating that S. viminalis had high accumulation potential of these elements. Furthermore, TF values were high for Cd, Mn, Sr, and Zn. Our results also demonstrated that soil element composition has major influence on the condition of S. viminalis individuals. Furthermore, visual condition assessment was found to be a useful tool to assess the phytoextraction potential of trees.

Coastal structures, waste materials and fishery enhancement

Energy Technology Data Exchange (ETDEWEB)

Collins, K.J.; Jensen, A.C.; Lockwood, A.P.M.; Lockwood, S.J. [University of Southampton, Southampton (United Kingdom). Dept. of Oceanography

1994-09-01

Current UK practice relating to the disposal of material at sea is reviewed. The use of stabilization technology relating to bulk waste materials, coal ash, oil ash and incinerator ash is discussed. The extension of this technology to inert minestone waste and tailings, contaminated dredged sediments and phosphogypsum is explored. Uses of stabilized wastes are considered in the areas of habitat restoration, coastal defense and fishery enhancement. It is suggested that rehabilitation of marine dump sites receiving loose waste such as pulverized fuel ash (PFA) could be enhanced by the continued dumping of the material but in a stabilized block form, so creating new habitat diversity. Global warming predictions include sea level rise and increased storm frequency. This is of particular concern along the southern and eastern coasts of the UK. The emphasis of coastal defense is changing from hard seawalls to soft options which include offshore barriers to reduce wave energy reaching the coast. Stabilized waste materials could be included in these and other marine constructions with possible economic benefit. Ministry of Agriculture, Fisheries and Food (MAFF), the regulatory authority in England and Wales for marine disposal/construction, policy regarding marine structures and fishery enhancement is outlined. A case is made for the inclusion of fishery enhancement features in future coastal structures. Examples of the productivity of man-made structures are given. Slight modification of planned structures and inclusion of suitable habitat niches could allow for the cultivation of kelp, molluscs, crustacea and fish.

Towards practical cadmium phytoextraction with Noccaea caerulescens.

Science.gov (United States)

Simmons, R W; Chaney, R L; Angle, J S; Kruatrachue, M; Klinphoklap, S; Reeves, R D; Bellamy, P

2015-01-01

A series of field trials were conducted to investigate the potential of Noccaea caerulescens F.K. Mey [syn. Thlaspi caerulescens J &C Presl. (see Koch and Al-Shehbaz 2004)] populations (genotypes) derived from southern France to phytoextract localized Cd/Zn contamination in Thailand. Soil treatments included pH variation and fertilization level and application of fungicide. N. caerulescens populations were transplanted to the field plots three months after germination and harvested in May, prior to the onset of seasonal rains. During this period growth was rapid with shoot biomass ranging from 0.93-2.2 g plant(-1) (280-650 kg ha(-1)) DW. Shoot Cd and Zn concentrations for the four populations evaluated ranged from 460-600 and 2600-2900 mg kg(-1) DW respectively. Cadmium and Zn Translocation Factors (shoot/root) for the populations tested ranged from 0.91-1.0 and 1.7-2.1 and Bioaccumulation Factors ranged from 12-15 and 1.2-1.3. We conclude that optimizing the use of fungicidal sprays, acidic soil pH, planting density and increasing the effective cropping period will increase rates of Cd and Zn removal enough to facilitate practical Cd phytoextraction from rice paddy soils in Thailand.

Phytoextraction of heavy metal from sewage sludge by plants

Directory of Open Access Journals (Sweden)

Jaroslava Bartlová

2010-01-01

Full Text Available In 2008 and 2009, studies made contents of cadmium and lead in the soil and their uptake by non-traditional plants were studied in a small-plot trial. At the same time also the effect of bio-algeen preparations on phytoextraction of heavy metals by these plants was investigated. Experimental plots were established on the reclaimed land after closing down mining operations in the town of Žacléř (North-East Bohemia where a layer of sewage sludge from a wastewater treatment plant 0.6–0.8 m thick was subsequently applied. The locality is situated in the altitude of 612 m, its average annual temperature is about 6.8 °C and the mean annual precipitations are 857 mm. Analyses revealed higher concentrations of heavy metals in the applied sewage sludge. The average concentrations of lead and cadmium were 180 mg . kg−1 and 6.89 mg . kg−1, respectively. The experiment had two variants: Variant 1 – sewage sludge without any other substances, and Variant 2 – sewage sludge + bio-algeen preparations (B. A. S-90 or B. A. Root Concentrate. To find the most suitable plant species for the phytoextraction of cadmium and lead, the following non-traditional plants were cultivated in both variants: fodder mallow (Malva verticillata L., rye (Secale cereale L. var. multicaule METZG. ex ALEF. and white sweet clover (Melilotus alba MEDIC.. The highest accumulation of cadmium and lead in the aboveground biomass was found out in rye, viz 14.89 mg . kg−1 DM and 14.89 mg . kg−1 DM of Cd and Pb, respectively., As compared with other plants under study, white sweet clover exhibited the significantly lowest capability to extract both heavy metals from soil (viz 0.22 and 3.20 mg . kg−1 DM of Cd and Pb, respectively. A positive effect of bio-algeen on phytoextraction of cadmium and lead was evident in all plants. The highest yield of aboveground biomass was recorded on the plot with white sweet clover with added

The use of NTA for lead phytoextraction from soil from a battery recycling site.

Science.gov (United States)

Freitas, Eriberto Vagner de Souza; do Nascimento, Clístenes Williams Araújo

2009-11-15

The application of synthetic aminopolycarboxylic acids to soil increases metal solubility, and therefore enhances phytoextraction. However, synthetic chelants degrade poorly in soil, and metal leaching threatens human and animal health. The aim of this study is to assess the use of a biodegradable chelant (NTA) for Pb phytoextraction from a soil contaminated by battery-casing disposal. EDTA was also included in the experiment to assess the behavior of a non-degradable chelant. Each synthetic chelant was applied to soil pots cultivated with maize plants at rates of 0, 2, 5, 10, and 20 mmol kg(-1). Soil samples were extracted with CaCl(2) and by sequential extraction for Pb. In addition, a soil column experiment was set up to study the leaching of Pb from the chelant-amended soil. The results showed that both NTA and EDTA were highly effective in solubilizing Pb from soil. The Pb distribution into soil fractions after chelant addition followed the sequence: Ex (exchangeable)>OM (organic matter)>AFeOx (amorphous iron oxides)>CFeOx (crystalline iron oxides). The 5 mmol kg(-1) dose of EDTA increased the Pb concentration in maize shoots to 1.1%, but it promoted unacceptable Pb leaching rates. On the other hand, the results showed that phytoremediating the site using 5 mmol kg(-1) NTA could be feasible with no environmental effects due to Pb leaching over a five-year period.

Feasibility of phytoextraction to remediate cadmium and zinc contaminated soils.

Science.gov (United States)

Koopmans, G F; Römkens, P F A M; Fokkema, M J; Song, J; Luo, Y M; Japenga, J; Zhao, F J

2008-12-01

A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and Zn exceeded the decrease of the soluble metal concentrations by several orders of magnitude. Hence, desorption of metals must have occurred to maintain the soil solution concentrations. A coupled regression model was developed to describe the transfer of metals from soil to solution and plant shoots. This model was applied to estimate the phytoextraction duration required to decrease the soil Cd concentration from 10 to 0.5 mg kg(-1). A biomass production of 1 and 5 t dm ha(-1) yr(-1) yields a duration of 42 and 11 yr, respectively. Successful phytoextraction operations based on T. caerulescens require an increased biomass production.

Chelant-assisted phytoextraction and accumulation of Zn by Zea mays.

Science.gov (United States)

Gheju, M; Stelescu, I

2013-10-15

Zea mays plants were exposed to soils with concentrations of Zn ranging from 64 to 1800 mg kg(-1) dw, and the efficiency of three selected chelating agents (trisodium citrate (CI), disodium oxalate (OX) and disodium dihydrogen ethylene-diamine-tetraacetate (EDTA)) in enhancing metal phytoextraction was compared. Zn concentration in plant tissues increased in conjunction with the metal concentration of the soil. EDTA was found to be the most efficient chelating amendment, increasing concentrations of Zn in shoots from 88 mg kg(-1) dw, at 64 mg kg(-1) dw soil, to 8026 mg kg(-1) dw at 1800 mg kg(-1) dw soil. The overall orders of BCFs and TFs which resulted from this study are: EDTA > H2O > OX > CI, and EDTANa2 > OX > CI > H2O, respectively. The more effective uptake of Zn by plants for the control treatment (distilled water only) than for CI and OX was attributed to the neutral or slightly alkaline pH of the two chelant irrigation solutions. Instead, EDTA had a favorable effect on Zn uptake from soil due to its additive chelating and acidifying properties. Among the three chelants, only EDTA significantly increased the Zn phytoextraction potential of Z. mays, while CI and OX induced a low metal uptake from soil by plants. Although Z. mays has a lower Zn accumulation capacity than the hyperaccumulator Thlaspi caerulescens, it could be considered as a potential phytoremediator of soils with elevated Zn concentrations, especially when metal pollution extends to depths greater than 20 cm. Copyright © 2013 Elsevier Ltd. All rights reserved.

Willow Trees from Heavy Metals Phytoextraction as Energy Crops

Czech Academy of Sciences Publication Activity Database

Šyc, Michal; Pohořelý, Michael; Kameníková, Petra; Habart, J.; Svoboda, Karel; Punčochář, Miroslav

2012-01-01

Roč. 37, - (2012), s. 106-113 ISSN 0961-9534 R&D Projects: GA ČR(CZ) GA104/07/0977; GA MŠk 2B08048 Institutional research plan: CEZ:AV0Z40720504 Keywords : phytoextraction * heavy metal * incineration Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.975, year: 2012

Selection of ectomycorrhizal willow genotype in phytoextraction of heavy metals.

Science.gov (United States)

Hrynkiewicz, Katarzyna; Baum, Christel

2013-01-01

Willow clones are used for the phytoextraction of heavy metals from contaminated soils and are usually mycorrhizal. The receptiveness of willow clones for mycorrhizal inoculum varies specific to genotype; however, it is unknown if this might have a significant impact on their efficiency in phytoextraction of heavy metals. Therefore, a model system with mycorrhizal and non-mycorrhizal willows of two different genotypes--one with usually stronger natural mycorrhizal colonization (Salix dasyclados), and one with lower natural mycorrhizal colonization (S. viminalis)--was investigated for its efficiency of phytoextraction of heavy metals (Cd, Pb, Cu, Zn) from contaminated soil. Inoculation with the ectomycorrhizal fungus Amanita muscaria significantly decreased the biomass of leaves of both inoculated willow clones, and increased or had no effect on the biomass of trunks and roots of S. dasyclados and S. viminalis, respectively. The concentrations of heavy metals in the biomass of S. dasyclados were in general higher than in S. viminalis irrespective of inoculation with the ectomycorrhizal fungus. Inoculation with A. muscaria significantly decreased the concentration of Cu in the trunks of both Salix taxa, but did not affected the concentrations of other heavy metals in the biomass. In conclusion, stronger receptiveness of willow clones for mycorrhizal inoculum was correlated with an increased total extraction of heavy metals from contaminated soils. Therefore, this seems to be a suitable criterion for effective willow clone selection for phytoremediation. Increased biomass production with relatively constant metal concentrations seems to be a major advantage of mycorrhizal formation of willows in phytoremediation of contaminated soils.

Selenite resistant rhizobacteria stimulate SeO(3) (2-) phytoextraction by Brassica juncea in bioaugmented water-filtering artificial beds.

Science.gov (United States)

Lampis, Silvia; Ferrari, Anita; Cunha-Queda, A Cristina F; Alvarenga, Paula; Di Gregorio, Simona; Vallini, Giovanni

2009-09-01

putative ability of reducing Se(IV) to organo-Se compounds significantly enhanced either selenium absorption by the plants or active metalloid translocation to epigeous parts. Bioaugmentation with the bacterial strain S. malthophila SeITE02 is suggested to elicit selenite phytoextraction efficiency in B. juncea. Manipulation of synergistic interactions between plants having phytoextraction capabilities and their associated rhizobacteria may enhance already consolidated treatment processes aimed to detoxify selenite laden wastewater.

Phytoextraction crop disposal--an unsolved problem

International Nuclear Information System (INIS)

Sas-Nowosielska, A.; Kucharski, R.; Malkowski, E.; Pogrzeba, M.; Kuperberg, J.M.; Krynski, K.

2004-01-01

Several methods of contaminated crop disposal after phytoextraction process (composting, compaction, incineration, ashing, pyrolysis, direct disposal, liquid extraction) have been described. Advantages and disadvantages of methods are presented and discussed. Composting, compaction and pyrolysis are the pretreatment steps, since significant amount of contaminated biomass will still exist after each of the process. Four methods of final disposal were distinguished: incineration, direct disposal, ashing and liquid extraction. Among them, incineration (smelting) is proposed as the most feasible, economically acceptable and environmentally sound. - Methods of contaminated crop disposal are described and evaluated

Modeling the potential role of a forest ecosystem in phytostabilization and phytoextraction of 90Sr at a contaminated watershed

International Nuclear Information System (INIS)

Garten, C.T. Jr.

1999-01-01

The behavior of 90 Sr at forest sites in the White Oak Creek watershed, near Oak Ridge, Tennessee, was simulated with a simple, site-specific, multicompartment model that linked biomass and element cycling dynamics. The model was used to predict the role of forest cover in mitigating hydrologic losses of 90 Sr from contaminated soils (i.e. phytostabilization) under conditions where contaminant transport is governed mainly by shallow subsurface flow. The model was also used to predict the removal of 90 Sr from soil (i.e. phytoextraction) through the growth and harvest of short rotation woody crops over a period of 30 years. Simulations with the model indicated that (1) forest preservation on the watershed is a form of phytostabilization because forest cover helps to minimize hydrologic losses of 90 Sr and (2) an attempt to significantly reduce amounts of 90 Sr in soil through phytoextraction would be unsuccessful. Over a period of 30 years, and under various management strategies, the model predicted that 90 Sr initially present in soil at a contaminated site was lost through hydrologic transport and <53% was lost by radioactive decay. Phytostabilization may be important in the management of radioactive land when issues like waste minimization and pollution prevention affect the selection of technologies to be used in environmental restoration. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Predicting the phytoextraction duration to remediate heavy metal contaminated soils

NARCIS (Netherlands)

Koopmans, G.F.; Römkens, P.F.A.M.; Song, J.; Temminghoff, E.J.M.; Japenga, J.

2007-01-01

The applicability of phytoextraction to remediate soils contaminated with heavy metals (HMs) depends on, amongst others, the duration before remediation is completed. The impact of changes in the HM content in soil occurring during remediation on plant uptake has to be considered in order to obtain

Phytoextraction of initial cutting of Salix matsudana for Cd and Cu.

Science.gov (United States)

Wang, Wen-Wen; Cheng, Liu Ke; Hao, Jie Wei; Guan, Xin; Tian, Xing-Jun

2016-06-27

Salix species are widely used as vegetation filters because of their flourishing root system and fast growth rate. However, studies have yet to determine whether the root system functions in vegetable filters with mixed heavy metal (HM) pollution or whether initial cutting participates in the phytoextraction of HMs. This study aims to determine the function of the root system and initial cutting as vegetation filters in the absorption and accumulation of Cd and Cu. Thick (>1 cm in diameter) and fine (phytoextraction capacity of plants. The initial cuttings could also absorb and accumulate HMs in the early growth stages of willow without roots. Cu inhibited the plant absorption and accumulation of Cd and promoted Cd transport to shoots. Cd inhibited the Cu absorption of the root system. Our study provided essential data regarding woody species as vegetation filters of HM pollution.

Influence of Rapeseed Cake on Heavy Metal Uptake by a Subsequent Rice Crop After Phytoextraction Using Sedum plumbizincicola.

Science.gov (United States)

Zhou, Liqiang; Wu, Longhua; Li, Zhu; Yang, Bingfan; Yin, Bin; Luo, Yongming; Christie, Peter

2015-01-01

A glasshouse pot experiment was conducted to study the effects of phytoextraction by Sedum plumbizincicola and application of rapeseed cake (RSC) on heavy metal accumulation by a subsequent rice (Oryza sativa L.) crop in a contaminated paddy soil collected from east China. After phytoextraction by S. plumbizincicola the soil and brown rice Cd concentrations effectively declined. After phytoextraction, RSC application reduced brown rice Cd concentrations in the subsequent rice crop to 0.23-0.28 mg kg(-1), almost down to the standard limit (0.2 mg kg(-1)). After phytoextraction and then application of RSC, the soil solution pH, dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) concentrations increased during early stages of rice growth resulting directly and indirectly in lowering the bioavailability of the heavy metals. Thus the grain yield of the subsequent rice crop increased and the heavy metals in the brown rice declined significantly. In this contaminated acid soil, growing the hyperaccumulator S. plumbizincicola and rice in rotation together with RSC application may therefore be regarded as a viable strategy for safe grain production and bioremediation.

Findings on the phytoextraction and phytostabilization of soils contaminated with heavy metals.

Science.gov (United States)

Cheraghi, M; Lorestani, B; Khorasani, N; Yousefi, N; Karami, M

2011-12-01

As a result of human activities such as mining, metal pollution has become one of the most serious environmental problems today. Phytoremediation, an emerging cost-effective, non-intrusive, and aesthetically pleasing technology that uses the remarkable ability of plants to concentrate elements can be potentially used to remediate metal-contaminated sites. The aim of this work was to assess the extent of metal accumulation by plants found in a mining area in Hamedan province with the ultimate goal of finding suitable plants for phytoextraction and phytostabilization (two processes of phytoremediation). To this purpose, shoots and roots of the 12 plant species and the associated soil samples were collected and analyzed by measurement of total concentrations of some elements (Fe, Mn, Zn, and Cu) using atomic absorption spectrophotometer and then biological absorption coefficient, bioconcentration factor, and translocation factor parameters calculated for each element. Our results showed that none of the plants were suitable for phytoextraction and phytostabilization of Fe, Zn, and Cu, while Chenopodium botrys, Stipa barbata, Cousinia bijarensis, Scariola orientalis, Chondrila juncea, and Verbascum speciosum, with a high biological absorption coefficient for Mn, were suitable for phytoextraction of Mn, and C. bijarensis, C. juncea, V. speciosum, S. orientalis, C. botrys, and S. barbata, with a high bioconcentration factor and low translocation factor for Mn, had the potential for the phytostabilization of this element.

Enhanced phytoextraction of germanium and rare earth elements - a rhizosphere-based approach

Science.gov (United States)

Wiche, Oliver

2016-04-01

Germanium (Ge) and rare earth elements (REEs) are economically valuable raw materials that have become an integral part of our modern high tech society. While most of these elements are not actually rare in terms of general amounts in the earth's crust, they are rarely found in sufficient abundances in single locations for their mining to be economically viable. The average concentration of Ge in soils is estimated at 1.6 μg g-1. The REEs comprise a group of 16 elements including La, the group of lanthanides and Y that are abundant in the earth crust with concentrations varying from 35 μg g-1 (La), 40 μg g-1 (Nd), 6 μg g-1 (Gd) and 3.5 μg g-1 (Er) to 0.5 μg g-1 in Tm. Thus, a promising chance to improve supply of these elements could be phytomining. Unfortunately, bioavailability of Ge and REEs in soils appears to be low, in particular in neutral or alkaline soils. A sequential dissolution analysis of 120 soil samples taken from the A-horizons of soils in the area of Freiberg (Saxony, Germany) revealed that only 0.2% of total Ge and about 0.5% of La, Nd, Gd and Er of bulk concentrations were easily accessible by leaching with NH4-acetate (pH 7). Most of the investigated elements were bound to Fe-/Mn-oxides and silicates and were therefore only poorly available for plant uptake. Here we report an environmentally friendly approach for enhanced phytoextraction of Ge and REEs from soils using mixed cultures of plant species with efficient mechanisms for the acquisition of nutrients in the rhizosphere. The rhizosphere is characterized as the zone in soil sourrounding a plant root that consists of a gradient in chemical, physical and biological soil properties driven by rhizodeposits like carboxylates and protons. Some species like white lupin (Lupinus albus) are able to excrete large amounts of organic acid anions(predominantly citrate and malate) and show a particularly high potential for the acidification of the rhizosphere. In our experiments, mixed cultures

Changes in metal availability, desorption kinetics and speciation in contaminated soils during repeated phytoextraction with the Zn/Cd hyperaccumulator Sedum plumbizincicola.

Science.gov (United States)

Li, Zhu; Jia, Mingyun; Wu, Longhua; Christie, Peter; Luo, Yongming

2016-02-01

Phytoextraction is one of the most promising technologies for the remediation of metal contaminated soils. Changes in soil metal availability during phytoremediation have direct effects on removal efficiency and can also illustrate the interactive mechanisms between hyperaccumulators and metal contaminated soils. In the present study the changes in metal availability, desorption kinetics and speciation in four metal-contaminated soils during repeated phytoextraction by the zinc/cadmium hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) over three years were investigated by chemical extraction and the DGT-induced fluxes in soils (DIFS) model. The available metal fractions (i.e. metal in the soil solution extracted by CaCl2 and by EDTA) decreased greatly by >84% after phytoextraction in acid soils and the deceases were dramatic at the initial stages of phytoextraction. However, the decreases in metal extractable by CaCl2 and EDTA in calcareous soils were not significant or quite low. Large decreases in metal desorption rate constants evaluated by DIFS were found in calcareous soils. Sequential extraction indicated that the acid-soluble metal fraction was easily removed by S. plumbizincicola from acid soils but not from calcareous soils. Reducible and oxidisable metal fractions showed discernible decreases in acid and calcareous soils, indicating that S. plumbizincicola can mobilize non-labile metal for uptake but the residual metal cannot be removed. The results indicate that phytoextraction significantly decreases metal availability by reducing metal pool sizes and/or desorption rates and that S. plumbizincicola plays an important role in the mobilization of less active metal fractions during repeated phytoextraction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Long-term field phytoextraction of zinc/cadmium contaminated soil by Sedum plumbizincicola under different agronomic strategies.

Science.gov (United States)

Deng, Lin; Li, Zhu; Wang, Jie; Liu, Hongyan; Li, Na; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Christie, Peter

2016-01-01

In two long-term field experiments the zinc (Zn)/cadmium (Cd) hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) was examined to optimize the phytoextraction of metal contaminated soil by two agronomic strategies of intercropping with maize (Zea mays) and plant densities. Soil total Zn and Cd concentrations decreased markedly after long-term phytoextraction. But shoot biomass and Cd and Zn concentrations showed no significant difference with increasing remediation time. In the intercropping experiment the phytoremediation efficiency in the treatment "S. plumbizincicola intercropped with maize" was higher than in S. plumbizincicola monocropping, and Cd concentrations of corn were below the maximum national limit. In the plant density experiment the phytoremediation efficiency increased with increasing plant density and 440,000 plants ha(-1) gave the maximum rate. These results indicated that S. plumbizincicola at an appropriate planting density and intercropped with maize can achieve high remediation efficiency to contaminated soil without affecting the cereal crop productivity. This cropping system combines adequate agricultural production with soil heavy metal phytoextraction.

Clonal variation in heavy metal accumulation and biomass production in a poplar coppice culture. II. Vertical distribution and phytoextraction potential

International Nuclear Information System (INIS)

Laureysens, I.; Temmerman, L. de; Hastir, T.; Gysel, M. van; Ceulemans, R.

2005-01-01

Short rotation coppice cultures (SRC) are intensively managed, high-density plantations of multi-shoot trees. In April 1996, an SRC field trial with 17 different poplar clones was established in Boom (Belgium) on a former waste disposal site. In December 1996 and January 2001, all shoots were cut back to a height of 5 cm to create a coppice culture. For six clones, wood and bark were sampled at the bottom, middle and top of a shoot in August and November 2002. No significant height effect of metal concentration was found, but for wood, metal concentrations generally increased toward the top of the shoot in August, and decreased toward the top of the shoot in November. Phytoextraction potential of a clone was primarily determined by metal concentration and by biomass production. Shoot size and number of shoots per stool were less important, as a high biomass production could be achieved by producing a few large shoots or many smaller shoots. Clone Fritzi Pauley accumulated 1.4 kg ha -1 of Al over two years; Wolterson and Balsam Spire showed a relatively high accumulation of Cd and Zn, i.e. averaging, respectively 47 and 57 g ha -1 for Cd and 2.4 and 2.0 kg ha -1 for Zn over two years. - Poplar shows potential for phytoextraction of Al, Cd and Zn on slightly contaminated soils

Clonal variation in heavy metal accumulation and biomass production in a poplar coppice culture. II. Vertical distribution and phytoextraction potential

Energy Technology Data Exchange (ETDEWEB)

Laureysens, I. [University of Antwerp, Campus Drie Eiken, Department of Biology, Universiteitsplein 1, B-2610 Wilrijk (Belgium)]. E-mail: ilse.laureysens@ua.ac.be; Temmerman, L. de [Veterinary and Agrochemical Research Centre (VAR), Leuvensesteenweg 17, B-3080 Tervuren (Belgium); Hastir, T. [University of Antwerp, Campus Drie Eiken, Department of Biology, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Gysel, M. van [University of Antwerp, Campus Drie Eiken, Department of Chemistry, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Ceulemans, R. [University of Antwerp, Campus Drie Eiken, Department of Biology, Universiteitsplein 1, B-2610 Wilrijk (Belgium)

2005-02-01

Short rotation coppice cultures (SRC) are intensively managed, high-density plantations of multi-shoot trees. In April 1996, an SRC field trial with 17 different poplar clones was established in Boom (Belgium) on a former waste disposal site. In December 1996 and January 2001, all shoots were cut back to a height of 5 cm to create a coppice culture. For six clones, wood and bark were sampled at the bottom, middle and top of a shoot in August and November 2002. No significant height effect of metal concentration was found, but for wood, metal concentrations generally increased toward the top of the shoot in August, and decreased toward the top of the shoot in November. Phytoextraction potential of a clone was primarily determined by metal concentration and by biomass production. Shoot size and number of shoots per stool were less important, as a high biomass production could be achieved by producing a few large shoots or many smaller shoots. Clone Fritzi Pauley accumulated 1.4 kg ha{sup -1} of Al over two years; Wolterson and Balsam Spire showed a relatively high accumulation of Cd and Zn, i.e. averaging, respectively 47 and 57 g ha{sup -1} for Cd and 2.4 and 2.0 kg ha{sup -1} for Zn over two years. - Poplar shows potential for phytoextraction of Al, Cd and Zn on slightly contaminated soils.

Leaching variations of heavy metals in chelator-assisted phytoextraction by Zea mays L. exposed to acid rainfall.

Science.gov (United States)

Lu, Yayin; Luo, Dinggui; Liu, Lirong; Tan, Zicong; Lai, An; Liu, Guowei; Li, Junhui; Long, Jianyou; Huang, Xuexia; Chen, Yongheng

2017-11-01

Chelant-enhanced phytoextraction method has been put forward as an effective soil remediation method, whereas the heavy metal leaching could not be ignored. In this study, a cropping-leaching experiment, using soil columns, was applied to study the metal leaching variations during assisted phytoextraction of Cd- and Pb-polluted soils, using seedlings of Zea mays, applying three different chelators (EDTA, EDDS, and rhamnolipid), and artificial rainfall (acid rainfall or normal rainfall). It showed that artificial rainfall, especially artificial acid rain, after chelator application led to the increase of heavy metals in the leaching solution. EDTA increased both Cd and Pb concentrations in the leaching solution, obviously, whereas EDDS and rhamnolipid increased Cd concentration but not Pb. The amount of Cd and Pb decreased as the leaching solution increased, the patterns as well matched LRMs (linear regression models), with R-square (R 2 ) higher than 90 and 82% for Cd and Pb, respectively. The maximum cumulative Cd and Pb in the leaching solutions were 18.44 and 16.68%, respectively, which was amended by EDTA and acid rainwater (pH 4.5), and followed by EDDS (pH 4.5), EDDS (pH 6.5), rhamnolipid (0.5 g kg -1 soil, pH 4.5), and rhamnolipid (pH 6.5).

Phytoextraction of cadmium and zinc from arable soils amended with sewage sludge using Thlaspi caerulescens: Development of a predictive model

Energy Technology Data Exchange (ETDEWEB)

Maxted, A.P. [School of Biosciences, University of Nottingham, Biology Building, University Park, Nottingham NG7 2RD (United Kingdom); Black, C.R. [School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD (United Kingdom); West, H.M.; Crout, N.M.J. [School of Biosciences, University of Nottingham, Biology Building, University Park, Nottingham NG7 2RD (United Kingdom); McGrath, S.P. [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Young, S.D. [School of Biosciences, University of Nottingham, Biology Building, University Park, Nottingham NG7 2RD (United Kingdom)], E-mail: scott.young@nottingham.ac.uk

2007-12-15

The objectives of this study were to assess the potential for using Thlaspi caerulescens as a phytoextraction plant and develop a user-advice model, which can predict the frequency of phytoextraction operation required under prescribed conditions. Pot and field trials were conducted using soil collected from a dedicated sewage sludge disposal facility. Soil amendments (sulphuric acid, potassium chloride and EDTA) intended to increase Cd solubility were also tested. Predictive models of Cd and Zn uptake were developed which were able to reproduce the observed pH-dependence of Cd uptake with an apparent maximum around pH 6. Chemical treatments did not significantly increase the uptake of Cd. The periodic use of phytoextraction with T. caerulescens to maintain soils below statutory metal concentration limits, when modern sewage sludges are repeatedly applied, seems very attractive given the non-intrusive and cost-effective nature of the process. The major limitations lie with the large-scale husbandry of T. caerulescens. - A predictive model of Cd and Zn uptake by Thlaspi caerulescens is presented as a management tool in the phytoextraction of arable soils receiving sewage sludge.

Phytoextraction of cadmium and zinc from arable soils amended with sewage sludge using Thlaspi caerulescens: Development of a predictive model

International Nuclear Information System (INIS)

Maxted, A.P.; Black, C.R.; West, H.M.; Crout, N.M.J.; McGrath, S.P.; Young, S.D.

2007-01-01

The objectives of this study were to assess the potential for using Thlaspi caerulescens as a phytoextraction plant and develop a user-advice model, which can predict the frequency of phytoextraction operation required under prescribed conditions. Pot and field trials were conducted using soil collected from a dedicated sewage sludge disposal facility. Soil amendments (sulphuric acid, potassium chloride and EDTA) intended to increase Cd solubility were also tested. Predictive models of Cd and Zn uptake were developed which were able to reproduce the observed pH-dependence of Cd uptake with an apparent maximum around pH 6. Chemical treatments did not significantly increase the uptake of Cd. The periodic use of phytoextraction with T. caerulescens to maintain soils below statutory metal concentration limits, when modern sewage sludges are repeatedly applied, seems very attractive given the non-intrusive and cost-effective nature of the process. The major limitations lie with the large-scale husbandry of T. caerulescens. - A predictive model of Cd and Zn uptake by Thlaspi caerulescens is presented as a management tool in the phytoextraction of arable soils receiving sewage sludge

Succulent species differ substantially in their tolerance and phytoextraction potential when grown in the presence of Cd, Cr, Cu, Mn, Ni, Pb, and Zn.

Science.gov (United States)

Zhang, Chengjun; Sale, Peter W G; Clark, Gary J; Liu, Wuxing; Doronila, Augustine I; Kolev, Spas D; Tang, Caixian

2015-12-01

Plants for the phytoextraction of heavy metals should have the ability to accumulate high concentrations of such metals and exhibit multiple tolerance traits to cope with adverse conditions such as coexistence of multiple heavy metals, high salinity, and drought which are the characteristics of many contaminated soils. This study compared 14 succulent species for their phytoextraction potential of Cd, Cr, Cu, Mn, Ni, Pb, and Zn. There were species variations in metal tolerance and accumulation. Among the 14 succulent species, an Australian native halophyte Carpobrotus rossii exhibited the highest relative growth rate (20.6-26.6 mg plant(-1) day(-1)) and highest tolerance index (78-93%), whilst Sedum "Autumn Joy" had the lowest relative growth rate (8.3-13.6 mg plant(-1) day(-1)), and Crassula multicava showed the lowest tolerance indices (phytoextraction of these heavy metals than other species. These findings suggest that Carpobrotus rossii is a promising candidate for phytoextraction of multiple heavy metals, and the aquatic or semiterrestrial Crassula helmsii is suitable for phytoextraction of Cd and Zn from polluted waters or wetlands.

Development of a model to select plants with optimum metal phytoextraction potential.

Science.gov (United States)

Guala, Sebastián D; Vega, Flora A; Covelo, Emma F

2011-07-01

The aim of the present study is to propose a nonlinear model which provides an indicator for the maximum phytoextraction of metals to help in the decision-making process. Research into different species and strategies plays an important role in the application of phytoextraction techniques to the remediation of contaminated soil. Also, the convenience of species according to their biomass and pollutant accumulation capacities has gained important space in discussions regarding remediation strategies, whether to choose species with low accumulation capacities and high biomass or high accumulation capacities with low biomass. The effects of heavy metals in soil on plant growth are studied by means of a nonlinear interaction model which relates the dynamics of the uptake of heavy metals by plants to heavy metal deposed in soil. The model, presented theoretically, provides an indicator for the maximum phytoextraction of metals which depends on adjustable parameters of both the plant and the environmental conditions. Finally, in order to clarify its applicability, a series of experimental results found in the literature are presented to show how the model performs consistently with real data. The inhibition of plant growth due to heavy metal concentration can be predicted by a simple kinetic model. The model proposed in this study makes it possible to characterize the nonlinear behaviour of the soil-plant interaction with heavy metal pollution in order to establish maximum uptake values for heavy metals in the harvestable part of plants.

Chelate-assisted phytoextraction of lead from contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Cooper, E.M.; Sims, J.T.; Cunningham, S.D.; Huang, J.W.; Berti, W.R.

1999-12-01

Phytoextraction, a remediation strategy for lead (Pb)-contaminated soils that removes soil Pb through plant uptake and harvest, may be enhanced by use of synthetic chelates. The authors evaluated Pb desorption from four contaminated soils by seven chelates (CDTA, DTPA, EDDHA, EFTA, HEDTA, HEIDA, and NTA) at three rates. The three most effective chelates (CDTA, DTPA, and HEDTA) were used in greenhouse studies with an uncontaminated soil and a Pb-contaminated soil to determine the effect of chelate type and rate on growth, Pb uptake, and plant elemental composition. Lead desorption varied with chelate and soil and increased with chelate rate, averaging 948 mg Pb kg{sup {minus}1} at the 20 mmol kg{sup {minus}1} rate vs. 28 mg Pb kg{sup {minus}1} by the control. The general ranking of chelate effectiveness, based on total Pb desorbed, was HEDTA > CDTA > DTPA > EGTA > HEIDA > EDDHA {approximately} NTA. Plant uptake of Pb from the contaminated soil was enhanced by CDTA, DTPA, and HEDTA, but with even the most effective treatment (corn, high CDTA rate), the amount of Pb extracted by plants was rather low. Lead extractable by the Toxicity Characteristic Leaching Procedure (TCLP) was increased from 9 mg L{sup {minus}1} in the control to from 47 to 174 mg L{sup {minus}1} in soils treated with 20 mmol kg{sup {minus}1} CDTA or DTPA and chelates generally caused a shift in Pb from resistant to more soluble chemical fractions.

Citric acid enhances the phytoextraction of manganese and plant growth by alleviating the ultrastructural damages in Juncus effusus L

Energy Technology Data Exchange (ETDEWEB)

Najeeb, U.; Xu, L.; Ali, Shafaqat [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Jilani, Ghulam, E-mail: jilani@uaar.edu.pk [Department of Soil Science, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Punjab 46300 (Pakistan); Gong, H.J. [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Shen, W.Q. [The University of Nottingham at Ningbo, Ningbo 315100 (China); Zhou, W.J., E-mail: wjzhou@zju.edu.cn [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China)

2009-10-30

Chelate-assisted phytoextraction by high biomass producing plant species enhances the removal of heavy metals from polluted environments. In this regard, Juncus effusus a wetland plant has great potential. This study evaluated the effects of elevated levels of manganese (Mn) on the vegetative growth, Mn uptake and antioxidant enzymes in J. effusus. We also studied the role of citric acid and EDTA on improving metal accumulation, plant growth and Mn toxicity stress alleviation. Three-week-old plantlets of J. effusus were subjected to various treatments in the hydroponics as: Mn (50, 100 and 500 {mu}M) alone, Mn (500 {mu}M) + citric acid (5 mM), and Mn (500 {mu}M) + EDTA (5 mM). After 2 weeks of treatment, higher Mn concentrations significantly reduced the plant biomass and height. Both citric acid and EDTA restored the plant height as it was reduced at the highest Mn level. Only the citric acid (but not EDTA) was able to recover the plant biomass weight, which was also obvious from the microscopic visualization of mesophyll cells. There was a concentration dependent increase in Mn uptake in J. effusus plants, and relatively more deposition in roots compared to aerial parts. Although both EDTA and citric acid caused significant increase in Mn accumulation; however, the Mn translocation was enhanced markedly by EDTA. Elevated levels of Mn augmented the oxidative stress, which was evident from changes in the activities of antioxidative enzymes in plant shoots. Raised levels of lipid peroxidation and variable changes in the activities of antioxidant enzymes were recorded under Mn stress. Electron microscopic images revealed several modifications in the plants at cellular and sub-cellular level due to the oxidative damage induced by Mn. Changes in cell shape and size, chloroplast swelling, increased number of plastoglobuli and disruption of thylakoid were noticed. However, these plants showed a high degree of tolerance against Mn toxicity stress, and it removed

Citric acid enhances the phytoextraction of manganese and plant growth by alleviating the ultrastructural damages in Juncus effusus L

International Nuclear Information System (INIS)

Najeeb, U.; Xu, L.; Ali, Shafaqat; Jilani, Ghulam; Gong, H.J.; Shen, W.Q.; Zhou, W.J.

2009-01-01

Chelate-assisted phytoextraction by high biomass producing plant species enhances the removal of heavy metals from polluted environments. In this regard, Juncus effusus a wetland plant has great potential. This study evaluated the effects of elevated levels of manganese (Mn) on the vegetative growth, Mn uptake and antioxidant enzymes in J. effusus. We also studied the role of citric acid and EDTA on improving metal accumulation, plant growth and Mn toxicity stress alleviation. Three-week-old plantlets of J. effusus were subjected to various treatments in the hydroponics as: Mn (50, 100 and 500 μM) alone, Mn (500 μM) + citric acid (5 mM), and Mn (500 μM) + EDTA (5 mM). After 2 weeks of treatment, higher Mn concentrations significantly reduced the plant biomass and height. Both citric acid and EDTA restored the plant height as it was reduced at the highest Mn level. Only the citric acid (but not EDTA) was able to recover the plant biomass weight, which was also obvious from the microscopic visualization of mesophyll cells. There was a concentration dependent increase in Mn uptake in J. effusus plants, and relatively more deposition in roots compared to aerial parts. Although both EDTA and citric acid caused significant increase in Mn accumulation; however, the Mn translocation was enhanced markedly by EDTA. Elevated levels of Mn augmented the oxidative stress, which was evident from changes in the activities of antioxidative enzymes in plant shoots. Raised levels of lipid peroxidation and variable changes in the activities of antioxidant enzymes were recorded under Mn stress. Electron microscopic images revealed several modifications in the plants at cellular and sub-cellular level due to the oxidative damage induced by Mn. Changes in cell shape and size, chloroplast swelling, increased number of plastoglobuli and disruption of thylakoid were noticed. However, these plants showed a high degree of tolerance against Mn toxicity stress, and it removed substantial

Phytoextraction of lead from firing range soils with Vetiver grass

Science.gov (United States)

E. W. Wilde; R. L. Brigmon; D. L. Dunn; M. A. Heitkamp; D. C. Dagnan

2007-01-01

Vetiver grass (Vetiveria zizanoides) along with soil amendments were evaluated for phytoextraction of lead and other metals (zinc, copper, and iron) from the soil of an active firing range at the Savannah River Site, SC. Lead-contaminated soil (300-4,500 ppm/kg) was collected, dried, placed in pots, fertilized, and used as a medium for growing...

Novel Field Data on Phytoextraction: Pre-Cultivation With Salix Reduces Cadmium in Wheat Grains.

Science.gov (United States)

Greger, Maria; Landberg, Tommy

2015-01-01

Cadmium (Cd) is a health hazard, and up to 43% of human Cd intake comes from wheat products, since Cd accumulates in wheat grains. Salix spp. are high-accumulators of Cd and is suggested for Cd phytoextraction from agricultural soils. We demonstrate, in field, that Salix viminalis can remove Cd from agricultural soils and thereby reduce Cd accumulation in grains of wheat subsequently grown in a Salix-treated field. Four years of Salix cultivation reduce Cd concentration in the soil by up to 27% and in grains of the post-cultivated wheat by up to 33%. The higher the plant density of the Salix, the greater the Cd removal from the soil and the lower the Cd concentration in the grains of post-cultivated wheat, the Cd reduction remaining stable several years after Salix cultivation. The effect occurred in both sandy and clayey soil and in winter and spring bread wheat cultivars. Already one year of Salix cultivation significantly decrease Cd in post grown wheat grains. With this field experiment we have demonstrated that phytoextraction can reduce accumulation of a pollutant in post-cultivated wheat and that phytoextraction has no other observed effect on post-cultivated crops than reduced uptake of the removed pollutant.

Use and abuse of trace metal concentrations in plant tissue for biomonitoring and phytoextraction

International Nuclear Information System (INIS)

Mertens, Jan; Luyssaert, Sebastiaan; Verheyen, Kris

2005-01-01

Some plant species accumulate trace metals from the soil in their aboveground biomass. Therefore, some scientists have concluded that these species are suitable for biomonitoring trace metal concentrations in the soil or for removing excessive trace metals from the soil by means of phytoextraction. A significant correlation between the chemical composition of foliage and soil is not a sufficient condition for using the chemical composition of foliage as a biomonitor for the quality of the soil. The chemical composition of foliage can, however, provide additional information to the traditional soil samples. The phytoextraction potential of a plant species cannot solely be evaluated on the basis of the trace metal concentrations in the plant and soil tissue. Data on the depth of the rooting zone, the density of the soil and the harvestable biomass should also be taken into account. Although plant tissue analysis is a useful tool in a wide range of studies and applications, trace metal concentrations in plant tissue cannot be viewed in isolation. Instead it should be analysed and interpreted in relation to other information such as soil concentrations, rooted zone, biomass production, etc. - Plants that accumulate soil metals in their aboveground biomass are often incorrectly considered to be suitable for monitoring soil pollution or for phytoextraction purposes

Phytoextraction of cadmium by Ipomoea aquatica (water spinach) in hydroponic solution: effects of cadmium speciation.

Science.gov (United States)

Wang, Kai-Sung; Huang, Lung-Chiu; Lee, Hong-Shen; Chen, Pai-Ye; Chang, Shih-Hsien

2008-06-01

Phytoextraction is a promising technique to remediate heavy metals from contaminated wastewater. However, the interactions of multi-contaminants are not fully clear. This study employed cadmium, Triton X-100 (TX-100), and EDTA to investigate their interactions on phytotoxicity and Cd phytoextraction of Ipomoea aquatica (water spinach) in simulated wastewater. The Cd speciation was estimated by a chemical equilibrium model and MINEQL+. Statistic regression was applied to evaluate Cd speciation on Cd uptake in shoots and stems of I. aquatica. Results indicated that the root length was a more sensitive parameter than root weight and shoot weight. Root elongation was affected by Cd in the Cd-EDTA solution and TX-100 in the Cd-TX-100 solution. Both the root length and the root biomass were negatively correlated with the total soluble Cd ions. In contrast, Cd phytoextraction of I. aquatic was correlated with the aqueous Cd ions in the free and complex forms rather than in the chelating form. Additionally, the high Cd bioconcentration factors of I. aquatica (375-2227 l kg(-1) for roots, 45-144 l kg(-1) for shoots) imply that I. aquatica is a potential aquatic plant to remediate Cd-contaminated wastewater.

Heavy metal uptake and leaching from polluted soil using permeable barrier in DTPA-assisted phytoextraction.

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Zhao, Shulan; Shen, Zhiping; Duo, Lian

2015-04-01

Application of sewage sludge (SS) in agriculture is an alternative technique of disposing this waste. But unreasonable application of SS leads to excessive accumulation of heavy metals in soils. A column experiment was conducted to test the availability of heavy metals to Lolium perenne grown in SS-treated soils following diethylene triamine penta acetic acid (DTPA) application at rates of 0, 10 and 20 mmol kg(-1) soil. In order to prevent metal leaching in DTPA-assisted phytoextraction process, a horizontal permeable barrier was placed below the treated soil, and its effectiveness was also assessed. Results showed that DTPA addition significantly increased metal uptake by L. perenne shoots and metal leaching. Permeable barriers increased metal concentrations in plant shoots and effectively decreased metal leaching from the treated soil. Heavy metals in SS-treated soils could be gradually removed by harvesting L. perenne many times in 1 year and adding low dosage of DTPA days before each harvest.

Phytoextraction of Cd-contaminated soil by carambola (Averrhoa carambola) in field trials.

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Li, J T; Liao, B; Dai, Z Y; Zhu, R; Shu, W S

2009-08-01

Use of metal-accumulating woody species to extract metals from heavy metal contaminated soil has received more attention. While considerable studies have focused on the phytoextraction potential of willow (Salix spp.) and poplar (Populus spp.), similar information is rare for other woody species. Carambola (Averrhoa carambola) is a high-biomass tree and has been identified as a new Cd-accumulating species. The present study aimed to evaluate the Cd phytoextraction potential of carambola under field condition. After growing in a slightly Cd-contaminated site for about 170 d, the carambola stand initiated by seed-seedling with high planting density (encoded with "HD-1yr") attained a high shoot biomass yield of 18.6 t ha(-1) and extracted 213 g Cdha(-1), resulting in a 1.6-fold higher Cd removal efficiency than that of a contrasting stand established by grafted-seedling with low planting density (5.3% vs. 2%). That is, "HD-1yr" would remove 50% of the total soil Cd with 13yr, assuming that the Cd removal efficiency would not change over time. Further, one crop of "HD-1yr" significantly decreased (63-69%) the Cd uptake by subsequent vegetables. Among the four carambola stands established using grafted-seedling, the 2-yr-old stand exhibited the highest annual Cd removal efficiency (3.7%), which was yet lower than that of "HD-1yr". These results suggested that phytoextraction of Cd by carambola (especially for "HD-1yr" stand) presented a feasible option to clean up agricultural soils slightly contaminated by Cd.

Phytoextraction: a review on enhanced metal availability and plant accumulation Fitoextração: uma revisão sobre disponibilidade induzida e acumulação de metais em plantas

Directory of Open Access Journals (Sweden)

Clístenes Williams Araújo do Nascimento

2006-06-01

Full Text Available Phytoextraction has emerged as a novel approach to clean up metal-polluted soils in which plants are used to transfer toxic metals from soils to shoots. This review provides a synthesis of current knowledge on phytoextraction of metals from soils and their accumulation in plants. The objective is to integrate soil-related (root exudates and chemical amendments and biological advances to suggest research needs and future directions. As far as can be deduced from the literature, it will be some time before phytoextraction may be established as a commercial technology. For chemically-assisted phytoextraction, research has not shown easily biodegradable compounds to overcome the risks associated with the use of EDTA for poorly available metals in soils. On the other hand, significant progress has been made on the physiological and molecular aspects regarding tolerance and phytoaccumulation of metals in plants. A multidisciplinary approach is warranted to make phytoextraction a feasible commercial technology to remediate metal-polluted soils.A fitoextração é uma tecnologia emergente para despoluição de solos contaminados por metais pesados que usa plantas para transferir metais do solo para a parte aérea, a qual pode ser removida da área poluída. Esta revisão apresenta uma síntese do atual conhecimento sobre fitoextração de metais pesados do solo e sua acumulação em plantas. O objetivo é integrar em uma mesma discussão os avanços relacionados à química do solo (exsudação radicular e adição de agentes quelantes para aumentar a absorção e à biologia (tolerância a metais e melhoramento genético visando sugerir futuras pesquisas na área. Embora promissor, o atual estado de desenvolvimento da fitoextração ainda não permite estabelecê-la como uma tecnologia comercial. A pesquisa ainda não encontrou agentes quelantes facilmente biodegradáveis que possam substituir o EDTA na solubilização de metais pouco disponíveis em

Leaching characteristics of EDTA-enhanced phytoextraction of Cd and Pb by Zea mays L. in different particle-size fractions of soil aggregates exposed to artificial rain.

Science.gov (United States)

Lu, Yayin; Luo, Dinggui; Lai, An; Liu, Guowei; Liu, Lirong; Long, Jianyou; Zhang, Hongguo; Chen, Yongheng

2017-01-01

Chelator-assisted phytoextraction is an alternative and effective technique for the remediation of heavy metal-contaminated soils, but the potential for heavy metal leaching needs to be assessed. In the present study, a soil column cultivation-leaching experiment was conducted to investigate the Cd and Pb leaching characteristics during assisted phytoextraction of metal-contaminated soils containing different particle-size soil aggregates. The columns were planted with Zea mays "Zhengdan 958" seedlings and treated with combined applications of EDTA and simulated rainfall (pH 4.5 or 6.5). The results were as follows: (1) The greatest uptake of Cd and Pb by Z. mays was observed after treatment with EDTA (2.5 mmol kg -1 soil) and soil aggregates of  EDTA 2.5-1 (pH 6.5) > EDTA 2.5-2 (pH 4.5) > EDTA 2.5-4 (pH 4.5) > EDTA 2.5-2 (pH 6.5) > EDTA 2.5-4 (pH 6.5).

Comparison of EDTA- and citric acid-enhanced phytoextraction of heavy metals in artificially metal contaminated soil by Typha angustifolia.

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Muhammad, Dawood; Chen, Fei; Zhao, Jing; Zhang, Guoping; Wu, Feibo

2009-08-01

A pot experiment was conducted to study the performance of EDTA and citric acid (CA) addition in improving phytoextraction of Cd, Cu, Pb, and Cr from artificially contaminated soil by T. angustifolia. T. angustifolia showed the remarkable resistance to heavy metal toxicity with no visual toxic symptom including chlorosis and necrosis when exposed to metal stress. EDTA-addition significantly reduced plant height and biomass, compared with the control, and stunted plant growth, while 2.5 and 5 mM CA addition induced significant increases in root dry weight. EDTA, and 5 and 10 mM CA significantly increased shoot Cd, Pb, and Cr concentrations compared with the control, with EDTA being more effective. At final harvest, the highest shoot Cd, Cr, and Pb concentrations were recorded in the treatment of 5 mM EDTA addition, while maximal root Pb concentration was found at the 2.5 mM CA treatment. However, shoot Cd accumulation in the 10 mM CA treatment was 36.9% higher than that in 2.5 mM EDTA, and similar with that in 10 mM EDTA. Shoot Pb accumulation was lower in 10 mM CA than that in EDTA treatments. Further, root Cd, Cu, and Pb accumulation of CA treatments and shoot Cr accumulation in 5 or 10 mM CA treatments were markedly higher than that of control and EDTA treatments. The results also showed that EDTA dramatically increased the dissolution of Cu, Cr, Pb, and Cd in soil, while CA addition had less effect on water-soluble Cu, Cr, and Cd, and no effect on Pb levels. It is suggested that CA can be a good chelator candidate for T. angustifolia used for environmentally safe phytoextraction of Cd and Cr in soils.

Screening of sunflower cultivars for metal phytoextraction in a contaminated field prior to mutagenesis.

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Nehnevajova, Erika; Herzig, Rolf; Federer, Guido; Erismann, Karl-Hans; Schwitzguébel, Jean-Paul

2005-01-01

Sunflower can be used for the remediation of metal-contaminated soils. Its high biomass production makes this plant species interestingfor phytoextraction and using sunflower oil for a technical purpose may improve the economic balance of phytoremediation. The aim of the present field study was to screen 15 commercial cultivars of Helianthus annuus L. grown on metal-contaminated soil, to find out the variety with the highest metal extraction, which can be further improved by mutation or in vitro breeding procedures. Two different fertilizers (ammonium sulphate and ammonium nitrate) were also used to enhance the bioavailability of metals in soil Highly significant differences were observed within tested varieties for metal accumulation and extraction efficiency. Furthermore, ammonium nitrate increased cadmium extraction, whereas ammonium sulphate enhanced zinc and lead uptake in most tested cultivars. In this field-based sunflower screening, we found enhanced cumulative Cd, Zn, and Pb extraction efficiency by a factor 4.4 for Salut cultivar. We therefore emphasize that prior to any classical breeding or genetic engineering enhancing metal uptake potential, a careful screening of various genotypes should be done to select the cultivar with the naturally highest metal uptake and to start the genetic improvement with the best available plant material.

Limitations for phytoextraction management on metal-polluted soils with poplar short rotation coppice-evidence from a 6-year field trial.

Science.gov (United States)

Michels, E; Annicaerta, B; De Moor, S; Van Nevel, L; De Fraeye, M; Meiresonne, L; Vangronsveld, J; Tack, F M G; Ok, Y S; Meers, Erik

2018-01-02

Poplar clones were studied for their phytoextraction capacity in the second growth cycle (6-year growth) on a site in the Belgian Campine region, which is contaminated with Cd and Zn via historic atmospheric deposition of nearby zinc smelter activities. The field trial revealed regrowth problems for some clones that could not be predicted in the first growth cycle. Four allometric relations were assessed for their capacity to predict biomass yield in the second growth cycle. A power function based on the shoot diameter best estimates the biomass production of poplar with R 2 values between 0.94 and 0.98. The woody biomass yield ranged from 2.1 to 4.8 ton woody Dry Mass (DM) ha -1 y -1 . The primary goal was to reduce soil concentrations of metals caused by phytoextraction. Nevertheless, increased metal concentrations were determined in the topsoil. This increase can partially be explained by the input of metals from deeper soil layers in the top soil through litterfall. The phytoextraction option with poplar short rotation coppice in this setup did not lead to the intended soil remediation in a reasonable time span. Therefore, harvest of the leaf biomass is put forward as a crucial part of the strategy for soil remediation through Cd/Zn phytoextraction.

Potential for Phytoextraction of Cu by Sesamum indicum L. and Cyamopsis tetragonoloba L.: A Green Solution to Decontaminate Soil

Science.gov (United States)

Amin, Hira; Arain, Basir Ahmed; Abbasi, Muhammad Sadiq; Jahangir, Taj Muhammad; Amin, Farah

2018-02-01

Phytoextraction is a plant based-technique for removing toxic heavy metals from polluted soil. The experiment reported in this paper was undertaken to study the basic Cu phytoextraction potential of Sesamum indicum in comparison with Cyamopsis tetragonoloba for remediation of Cu contaminated soil in the framework of a pot-experiment. Plants were subjected to seven Cu concentrations (0, 25, 50, 100, 150, 200, and 300 mg kg-1 soil) for 12 weeks. The morphological (i.e. growth) and biochemical (i.e. chlorophyll) parameters of both the plant species were observed throughout the experimental period; the phytoextraction efficiency of S. indicum and C. tetragonoloba were also determined. Most growth parameters were reduced under high Cu stress. Our results shows that at low concentration (25 mg Cu kg-1) all the growth and biochemical parameters were increased but at elevated Cu concentrations, root length, shoot length, and biomass (fresh and dry) were all significantly decreased (p 1, bioaccumulation coefficient (BAC) > 1 and translocation factor (TF) > 1 established C. tetragonoloba as a potential candidate plant for the decontamination of slightly Cu-polluted soil where the growth of plants would not be impaired and the extraction of Cu could be maintained at satisfying levels. Therefore, the present study suggested that C. tetragonoloba could possibly be used as a viable tool for phytoextraction.

[Continuous remediation of heavy metal contaminated soil by co-cropping system enhanced with chelator].

Science.gov (United States)

Wei, Ze-Bin; Guo, Xiao-Fang; Wu, Qi-Tang; Long, Xin-Xian

2014-11-01

In order to elucidate the continuous effectiveness of co-cropping system coupling with chelator enhancement in remediating heavy metal contaminated soils and its environmental risk towards underground water, soil lysimeter (0.9 m x 0.9 m x 0.9 m) experiments were conducted using a paddy soil affected by Pb and Zn mining in Lechang district of Guangdong Province, 7 successive crops were conducted for about 2.5 years. The treatments included mono-crop of Sedum alfredii Hance (Zn and Cd hyperaccumulator), mono-crop of corn (Zea mays, cv. Yunshi-5, a low-accumulating cultivar), co-crop of S. alfredii and corn, and co-crop + MC (Mixture of Chelators, comprised of citric acid, monosodium glutamate waste liquid, EDTA and KCI with molar ratio of 10: 1:2:3 at the concentration of 5 mmol x kg(-1) soil). The changes of heavy metal concentrations in plants, soil and underground water were monitored. Results showed that the co-cropping system was suitable only in spring-summer seasons and significantly increased Zn and Cd phytoextraction. In autumn-winter seasons, the growth of S. alfredii and its phytoextraction of Zn and Cd were reduced by co-cropping and MC application. In total, the mono-crops of S. alfredii recorded a highest phytoextraction of Zn and Cd. However, the greatest reduction of soil Zn, Cd and Pb was observed with the co-crop + MC treatment, the reduction rates were 28%, 50%, and 22%, respectively, relative to the initial soil metal content. The reduction of this treatment was mainly attributed to the downwards leaching of metals to the subsoil caused by MC application. The continuous monitoring of leachates during 2. 5 year's experiment also revealed that the addition of MC increased heavy metal concentrations in the leaching water, but they did not significantly exceed the III grade limits of the underground water standard of China.

Growth and Cadmium Phytoextraction by Swiss Chard, Maize, Rice, Noccaea caerulescens, and Alyssum murale in Ph Adjusted Biosolids Amended Soils.

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Broadhurst, C Leigh; Chaney, Rufus L; Davis, Allen P; Cox, Albert; Kumar, Kuldip; Reeves, Roger D; Green, Carrie E

2015-01-01

Past applications of biosolids to soils at some locations added higher Cd levels than presently permitted. Cadmium phytoextraction would alleviate current land use constraints. Unamended farm soil, and biosolids amended farm and mine soils were obtained from a Fulton Co., IL biosolids management facility. Soils contained 0.16, 22.8, 45.3 mg Cd kg(-1) and 43.1, 482, 812 mg Zn kg(-1) respectively with initial pH 6.0, 6.1, 6.4. In greenhouse studies, Swiss chard (Beta vulgaris var. cicla), a Cd-accumulator maize (inbred B37 Zea mays) and a southern France Cd-hyperaccumulator genotype of Noccaea caerulescens were tested for Cd accumulation and phytoextraction. Soil pH was adjusted from ∼5.5-7.0. Additionally 100 rice (Oryza sativa) genotypes and the Ni-hyperaccumulator Alyssum murale were screened for potential phytoextraction use. Chard suffered phytotoxicity at low pH and accumulated up to 90 mg Cd kg(-1) on the biosolids amended mine soil. The maize inbred accumulated up to 45 mg Cd kg(-1) with only mild phytotoxicity symptoms during early growth at pH>6.0. N. caerulescens did not exhibit phytotoxicity symptoms at any pH, and accumulated up to 235 mg Cd kg(-1) in 3 months. Reharvested N. caerulescens accumulated up to 900 mg Cd kg(-1) after 10 months. Neither Alyssum nor 90% of rice genotypes survived acceptably. Both N. caerulescens and B37 maize show promise for Cd phytoextraction in IL and require field evaluation; both plants could be utilized for nearly continuous Cd removal. Other maize inbreds may offer higher Cd phytoextraction at lower pH, and mono-cross hybrids higher shoot biomass yields. Further, maize grown only for biomass Cd maximum removal could be double-cropped.

Potential of Brassic rapa, Cannabis sativa, Helianthus annuus and Zea mays for phytoextraction of heavy metals from calcareous dredged sediment derived soils.

Science.gov (United States)

Meers, E; Ruttens, A; Hopgood, M; Lesage, E; Tack, F M G

2005-10-01

Remediation of soil pollution is one of the many current environmental challenges. Anthropogenic activity has resulted in the contamination of extended areas of land, the remediation of which is both invasive and expensive by conventional means. Phytoextraction of heavy metals from contaminated soils has the prospect of being a more economic in situ alternative. In addition, phytoextraction targets ecotoxicologically the most relevant soil fraction of these metals, i.e. the bioavailable fraction. Greenhouse experiments were carried out to evaluate the potential of four high biomass crop species in their potential for phytoextraction of heavy metals, with or without with the use of soil amendments (EDTA or EDDS). A calcareous dredged sediment derived surface soil, with high organic matter and clay content and moderate levels of heavy metal pollution, was used in the experiments. No growth depression was observed in EDTA or EDDS treated pots in comparison to untreated controls. Metal accumulation was considered to be low for phytoextraction purposes, despite the use of chelating agents. The low observed shoot concentrations of heavy metals were attributed to the low phytoavailability of heavy metals in this particular soil substrate. The mobilising effects induced by EDTA in the soil were found to be too long-lived for application as a soil amendment in phytoextraction. Although EDDS was found to be more biodegradable, higher effect half lives were observed than reported in literature or observed in previous experiments. These findings caution against the use of any amendment, biodegradable or otherwise, without proper investigation of its effects and the longevity thereof.

Phytoextraction of toxic trace elements by Sorghum bicolor inoculated with Streptomyces pactum (Act12) in contaminated soils.

Science.gov (United States)

Ali, Amjad; Guo, Di; Mahar, Amanullah; Wang, Ping; Ma, Fang; Shen, Feng; Li, Ronghua; Zhang, Zengqiang

2017-05-01

The increasing industrial, mining and agricultural activities have intensified the release of potential toxic trace elements (PTEs), which are of great concern to human health and environment. The alarming increase in PTEs concentration, stress the need for biotechnological remediation approaches. In order to assist phytoextraction of PTEs, different combinations of Streptomyces pactum (Act12) with biochar were applied to mining and industrial polluted soils of Shaanxi and Hunan Provinces of China, respectively. Act12 affected soil physico-chemical properties in both soils. Bioavailable Zn and Pb increased due to microbial activities, while Cd decreased by adsorption on biochar surface. Phytoextraction of Zn and Pb occurred in TG and CZ soil, while Cd uptake decreased in iron rich CZ soil by conflicting effect of siderophores. Cd in sorghum shoot was below detection level, but uptake increased in the roots due to minimum available fraction in TG soil. Biochar reduced the shoot and root uptake of Cd. Sorghum shoot, root dry weight and chlorophyll significantly increased after Act12 and biochar application. β-glucosidase, alkaline phosphatase and urease activities were significantly enhanced by Act12. Antioxidant enzymatic activities (POD, PAL and PPO) and lipid peroxidation (MDA) were decreased after the application of Act12 and biochar by reduced PTEs stress. Act12 and biochar can be used for different crops to enumerate the transfer rate of PTEs into the food chain. Copyright © 2017 Elsevier Inc. All rights reserved.

Induced Phytoextraction of Lead Through Chemical Manipulation of Switchgrass and Corn; Role of Iron Supplement.

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Johnson, Deayne M; Deocampo, Daniel M; El-Mayas, Hanan; Greipsson, Sigurdur

2015-01-01

The effects of combined chemical application of benomyl, ethylenedianinetetraacetate (EDTA), and iron (Fe) (foliar and root) on lead (Pb) phytoextraction by switchgrass (Panicum virgatum) and corn (Zea mays) was examined. Switchgrass was grown in Pb-contaminated urban topsoil with the following treatments: (C) Control, (B) benomyl, (E) EDTA, (F) foliar-Fe, (BE) benomyl + EDTA, (BF) benomyl + foliar-Fe, (FE) foliar-Fe + EDTA, (BFE) benomyl + foliar-Fe + EDTA. Corn was grown in sand-culture supplemented with Pb (500 mg kg(-1)) with the following treatments: (C) control, (B) benomyl, (E) EDTA, (F) root-Fe, (BE) benomyl + EDTA, (BF) benomyl + root-Fe, (FE) root-iron + EDTA, and, (BFE) benomyl + root-Fe + EDTA. All treatments were replicated three times and pots were arranged in a completely randomized design. Plants were analyzed for element concentration (Fe, Zn, P, and Pb) using either inductively coupled plasma (argon) atomic emission spectroscopy (ICP-AES) or graphite furnace atomic absorption spectrometer. Iron supplementation (foliar and root) affected Pb-translocation in plants. Foliar-Fe treatment increased translocation ratio of Pb (TF-Pb) significantly compared to other treatments with the exception of plants treated with benomyl and BF. Root-Fe treatment in combination with EDTA (FE) increased TF-Pb significantly compared to other treatments. Phytoextraction was improved by the combined chemical application; plants treated with BFE treatment increased Pb-total-phytoextraction by 424% compared to Control plants.

Solid Waste Biodegradation Enhancements and the Evaluation of Analytical Methods Used to Predict Waste Stability

OpenAIRE

Kelly, Ryan J.

2002-01-01

Conventional landfills are built to dispose of the increasing amount of municipal solid waste (MSW) generated each year. A relatively new type of landfill, called a bioreactor landfill, is designed to optimize the biodegradation of the contained waste to stabilized products. Landfills with stabilized waste pose little threat to the environment from ozone depleting gases and groundwater contamination. Limited research has been done to determine the importance of biodegradation enhancement tech...

Model evaluation of the phytoextraction potential of heavy metal hyperaccumulators and non-hyperaccumulators.

Science.gov (United States)

Liang, Hong-Ming; Lin, Ting-Hsiang; Chiou, Jeng-Min; Yeh, Kuo-Chen

2009-06-01

Evaluation of the remediation ability of zinc/cadmium in hyper- and non-hyperaccumulator plant species through greenhouse studies is limited. To bridge the gap between greenhouse studies and field applications for phytoextraction, we used published data to examine the partitioning of heavy metals between plants and soil (defined as the bioconcentration factor). We compared the remediation ability of the Zn/Cd hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri and the non-hyperaccumulators Nicotiana tabacum and Brassica juncea using a hierarchical linear model (HLM). A recursive algorithm was then used to evaluate how many harvest cycles were required to clean a contaminated site to meet Taiwan Environmental Protection Agency regulations. Despite the high bioconcentration factor of both hyperaccumulators, metal removal was still limited because of the plants' small biomass. Simulation with N. tabacum and the Cadmium model suggests further study and development of plants with high biomass and improved phytoextraction potential for use in environmental cleanup.

Phytoextraction potential of sunflower and white mustard plants in zinc-contaminated soil

Directory of Open Access Journals (Sweden)

Marta Zalewska

2014-12-01

Full Text Available Phytoextraction relies on plants with a high capacity to absorb heavy metals and remove them from the soil. The objective of this study was to analyze the potential of sunflower (Helianthus annuus L. and white mustard (Sinapis alba L. for phytoextraction of Zn-contaminated soil. Research was based on a strict pot experiment conducted in a greenhouse. Seven treatments were established with increasing Zn concentrations: 0, 25, 50, 100, 200, 400, and 600 mg Zn kg-1 air-dry soil. The first tested plant was fodder sunflower. In the following year, white mustard was sown in the same pots. Plants were harvested at the end of the flowering stage. The toxic effect of Zn on sunflower yields occurred at the contamination level of 200 mg Zn kg-1 soil. In the second year of the experiment, a significant decrease in mustard biomass took place in response to 400 mg Zn kg-1 soil. The contamination level of 600 mg Zn kg-1 soil resulted in complete plant death. Plant growth was not inhibited even at high tissue Zn concentrations of 515 mg Zn kg-1 sunflower DM and 422 mg Zn kg-1 mustard DM. The 2-yr cropping system did not contribute to a significant decrease in soil Zn content. Despite high concentrations of Zn in sunflower and mustard plants, total Zn uptake accounted for only 1% to 8% of the Zn rate introduced into the soil. However, in the long run, the growing of crops could reduce Zn contamination levels in the soil. The relatively high tolerance of sunflower and white mustard for Zn contamination and rapid growth of these species are possible alternatives for phytoextraction and phytostabilization of Zn-contaminated soil.

Indução da fitoextração de chumbo por ácido cítrico em solo contaminado por baterias automotivas Citric acid enhances lead phytoextraction from a soil contaminated by automotive batteries

Directory of Open Access Journals (Sweden)

Eriberto Vagner de Souza Freitas

2009-04-01

to their biodegradability. The study aimed at evaluating the performance of single and split applications of citric acid on enhancing Pb extraction by maize plants (Zea mays grown in soil samples from an area contaminated with Pb from battery wastes. The citric acid was applied at concentrations of 0, 20, 40, 60, and 80 mmol kg-1, either in a single dose on the30th day of growth or split in two, on the 30th and 34th day. Soil samples were subjected to chemical extraction by CaCl2 and fractionation. Results showed that splitting the citric acid doses did not improve the effectiveness of phytoextraction. A single application is therefore more suitable for Pb accumulation in plants. Enhanced phytoextraction using citric acid is feasible in a relatively short term and with no secondary problems due to Pb leaching. Citric acid amendment mobilized Pb from the least soluble fractions (bound to organic matter and iron oxides into the exchangeable form. The distribution pattern of Pb in soil fractions treated with citric acid followed the order: exchangeable > organic matter > crystalline iron oxide > amorphous iron oxide.

Application of phytoextraction for uranium contaminated soil in korea

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Ryu, Y.; Han, Y.; Lee, M.

2013-12-01

The soils having high concentration of uranium, sampled from Goesan Deokpyungri area in Korea, were identified with the uranium removal efficiency of phytoextraction by using several plants. According to the results of physicochemical properties, uranium concentration from soil was 28.85mg/kg, pH 5.43 and soil texture was "Sand". Results of SEP(Sequential Extraction Procedure) test, uranium concentrations ratio of soil in the status of exchangeable/carbonate was 13.4%. Five plants such as Lettuce (Lactuca sativa L.), Chinese cabbage (Brassica campestris L.), Sweet potato (Ipomoea batatas (L.) Lam), Radish (Raphanus sativus), Sesame (Perilla frutescens var. japonica) were cultivated during 56 days in phytotron. All the cultivation processes were conducted in a growth chamber at 25 degrees celsius, 70% relative humidity, 4000 Lux illumination (16 hours/day) and CO2 concentration of 600 ppm. Four times at intervals of 2 weeks leaves and roots collected were analyzed for uranium concentration. Ranges of uranium concentration of the roots and leaves from the five plants were measured to 206.81-721.22μg/kg and 3.45-10.21μg/kg respectively. The majority of uranium was found to accumulate in the roots. Uranium concentration in the leaves, regardless of the type of plants were presented below standard of drinking water(30μg/l) by U.S EPA. Phytoextraction pot experiments with citric acid were conducted. Citric acid as chelating agent was applied to soil to enhance uranium accumulation in five crop plants. 6 days before harvest crops, Each citric acid 25mM and 50mM was injected into the soil by 300ml. After injecting citric acid 25mM , pH of the soil was reduced to 4.95. Uranium concentration of leaves and roots collected from five plants was increased to 2-4times and 7-30times compared to control soil. Injected with citric acid 50mM , pH of the soil was reduced to 4.79. Uranium concentration of leaves and roots collected from five plants was increased to 3-10times and 10

Use and abuse of trace metal concentrations in plant tissue for biomonitoring and phytoextraction

NARCIS (Netherlands)

Mertens, Jan; Luyssaert, Sebastiaan; Verheyen, Kris

2005-01-01

Some plant species accumulate trace metals from the soil in their aboveground biomass. Therefore, some scientists have concluded that these species are suitable for biomonitoring trace metal concentrations in the soil or for removing excessive trace metals from the soil by means of phytoextraction.

Feasibility of Pb phytoextraction using nano-materials assisted ryegrass: Results of a one-year field-scale experiment.

Science.gov (United States)

Liang, Shu-Xuan; Jin, Yu; Liu, Wei; Li, Xiliang; Shen, Shi-Gang; Ding, Ling

2017-04-01

The effect of the combined application of nano-hydroxyapatite (NHAP) or nano-carbon black (NCB) on the phytoextraction of Pb by ryegrass was investigated as an enhanced remediation technique for soils by field-scale experiment. After the addition of 0.2% NHAP or NCB to the soil, temporal variation of the uptake of Pb in aboveground parts and roots were observed. Ryegrass shoot concentrations of Pb were lower with nano-materials application than without nano-materials for the first month. However, the shoot concentrations of Pb were significantly increased with nano-materials application, in particular NHAP groups. The ryegrass root concentrations of Pb were lower with nano-materials application for the first month. These results indicated that nano-materials had significant effects on stabilization of lead, especially at the beginning of the experiment. Along with the experimental proceeding, phytotoxicity was alleviated after the incorporation of nano-materials. The ryegrass biomass was significantly higher with nano-materials application. Consequently, the Pb phytoextraction potential of ryegrass significantly increased with nano-materials application compared to the gounps without nano-materials application. The total removal rates of soil Pb were higher after combined application of NHAP than NCB. NHAP is more suitable than NCB for in-situ remediation of Pb-contaminated soils. The ryegrass translocation factor exhibited a marked increase with time. It was thought that the major role of NHP and NBA might be to alleviate the Pb phytotoxicity and increase biomass of plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Saponification of fatty slaughterhouse wastes for enhancing anaerobic biodegradability.

Science.gov (United States)

Battimelli, Audrey; Carrère, Hélène; Delgenès, Jean-Philippe

2009-08-01

The thermochemical pretreatment by saponification of two kinds of fatty slaughterhouse waste--aeroflotation fats and flesh fats from animal carcasses--was studied in order to improve the waste's anaerobic degradation. The effect of an easily biodegradable compound, ethanol, on raw waste biodegradation was also examined. The aims of the study were to enhance the methanisation of fatty waste and also to show a link between biodegradability and bio-availability. The anaerobic digestion of raw waste, saponified waste and waste with a co-substrate was carried out in batch mode under mesophilic and thermophilic conditions. The results showed little increase in the total volume of biogas, indicating a good biodegradability of the raw wastes. Mean biogas volume reached 1200 mL/g VS which represented more than 90% of the maximal theoretical biogas potential. Raw fatty wastes were slowly biodegraded whereas pretreated wastes showed improved initial reaction kinetics, indicating a better initial bio-availability, particularly for mesophilic runs. The effects observed for raw wastes with ethanol as co-substrate depended on the process temperature: in mesophilic conditions, an initial improvement was observed whereas in thermophilic conditions a significant decrease in biodegradability was observed.

Phytoextraction potential of water fern (Azolla pinnata) in the removal of a hazardous dye, methyl violet 2B: Artificial neural network modelling.

Science.gov (United States)

Kooh, Muhammad Raziq Rahimi; Lim, Linda B L; Lim, Lee-Hoon; Malik, Owais Ahmed

2018-04-16

This study investigated the potential of Azolla pinnata (AP) in the removal of toxic methyl violet 2B (MV) dye wastewater using the phytoextraction approach with the inclusion of an Artificial Neural Network (ANN) modelling. Parameters examined included the effects of dye concentration, pH and plant dosage. The highest removal efficiency was 93% which was achieved at a plant dosage of 0.8 g (dye volume = 200 mL, initial pH = 6.0, initial dye concentration = 10 mg L -1 ). A significant decrease in relative frond number (RFN), a growth rate estimator, observed at a dye concentration of 20 mg L -1 MV indicated some toxicity, which coincided with the plant pigments studies where the chlorophyll a content was lower than the control. There were little differences in the plant pigment contents between the control and those in the presence of dye (5 to 15 mg L -1 ) indicating the tolerance of AP to MV at lower concentrations. A three-layer ANN model was optimized (6 neurons in the hidden layer) and successfully predicted the phytoextraction of MV (R = 0.9989, RMSE = 0.0098). In conclusion, AP proved to be a suitable plant that could be used for the phytoextraction of MV while the ANN modelling has shown to be a reliable method for the modelling of phytoextraction of MV using AP.

Comparison of willow and sunflower for uranium phytoextraction induced by citric acid

International Nuclear Information System (INIS)

Jan Mihalik; National Radiation Protection Institute, Prague; CZU, FAPPZ, Prague; Pavel Tlustos; Jirina Szakova

2010-01-01

This study deals with an efficiency of a low dose of citric acid soil application on phytoextraction of uranium. Willow (Salix spp.) and sunflower (Helianthus annus L.) were tested in this experiment with contaminated soil. The enhancing of uranium bioaccumulation was confirmed, but in contrast to previous studies, the highest quantity of uranium was accumulated in leaves. After 5 weeks of citric acid treatment, willow was more efficient in the uptake and translocation of uranium than sunflower. The transfer coefficient calculated for leaves increased from 0.033 (control) to 0.74, or 0.56 after five doses of 5 mmol of citric acid per 1 kg of soil for willow or sunflower, respectively. The uptake characterized by the total U content achieved 88 and 108 mg kg -1 in relation to the above ground parts of sunflower and willow, respectively. Even though both plants accumulated U in their above ground parts in significant rate, they employed diverse ways to achieve it. At the end of the treatment, the physiological condition of the plants enabled us to continue this method. (author)

Hyperaccumulator straw improves the cadmium phytoextraction efficiency of emergent plant Nasturtium officinale.

Science.gov (United States)

Li, Keqiang; Lin, Lijin; Wang, Jin; Xia, Hui; Liang, Dong; Wang, Xun; Liao, Ming'an; Wang, Li; Liu, Li; Chen, Cheng; Tang, Yi

2017-08-01

With the development of economy, the heavy metal contamination has become an increasingly serious problem, especially the cadmium (Cd) contamination. The emergent plant Nasturtium officinale R. Br. is a Cd-accumulator with low phytoremediation ability. To improve Cd phytoextraction efficiency of N. officinale, the straw from Cd-hyperaccumulator plants Youngia erythrocarpa, Galinsoga parviflora, Siegesbeckia orientalis, and Bidens pilosa was applied to Cd-contaminated soil and N. officinale was then planted; the study assessed the effect of hyperaccumulator straw on the growth and Cd accumulation of N. officinale. The results showed that application of hyperaccumulator species straws increased the biomass and photosynthetic pigment content and reduced the root/shoot ratio of N. officinale. All straw treatments significantly increased Cd content in roots, but significantly decreased Cd content in shoots of N. officinale. Applying hyperaccumulator straw significantly increased the total Cd accumulation in the roots, shoots, and whole plants of N. officinale. Therefore, application of straw from four hyperaccumulator species promoted the growth of N. officinale and improved the phytoextraction efficiency of N. officinale in Cd-contaminated paddy field soil; the straw of Y. erythrocarpa provided the most improvement.

Enhancing e-waste estimates: Improving data quality by multivariate Input–Output Analysis

Energy Technology Data Exchange (ETDEWEB)

Wang, Feng, E-mail: fwang@unu.edu [Institute for Sustainability and Peace, United Nations University, Hermann-Ehler-Str. 10, 53113 Bonn (Germany); Design for Sustainability Lab, Faculty of Industrial Design Engineering, Delft University of Technology, Landbergstraat 15, 2628CE Delft (Netherlands); Huisman, Jaco [Institute for Sustainability and Peace, United Nations University, Hermann-Ehler-Str. 10, 53113 Bonn (Germany); Design for Sustainability Lab, Faculty of Industrial Design Engineering, Delft University of Technology, Landbergstraat 15, 2628CE Delft (Netherlands); Stevels, Ab [Design for Sustainability Lab, Faculty of Industrial Design Engineering, Delft University of Technology, Landbergstraat 15, 2628CE Delft (Netherlands); Baldé, Cornelis Peter [Institute for Sustainability and Peace, United Nations University, Hermann-Ehler-Str. 10, 53113 Bonn (Germany); Statistics Netherlands, Henri Faasdreef 312, 2492 JP Den Haag (Netherlands)

2013-11-15

Highlights: • A multivariate Input–Output Analysis method for e-waste estimates is proposed. • Applying multivariate analysis to consolidate data can enhance e-waste estimates. • We examine the influence of model selection and data quality on e-waste estimates. • Datasets of all e-waste related variables in a Dutch case study have been provided. • Accurate modeling of time-variant lifespan distributions is critical for estimate. - Abstract: Waste electrical and electronic equipment (or e-waste) is one of the fastest growing waste streams, which encompasses a wide and increasing spectrum of products. Accurate estimation of e-waste generation is difficult, mainly due to lack of high quality data referred to market and socio-economic dynamics. This paper addresses how to enhance e-waste estimates by providing techniques to increase data quality. An advanced, flexible and multivariate Input–Output Analysis (IOA) method is proposed. It links all three pillars in IOA (product sales, stock and lifespan profiles) to construct mathematical relationships between various data points. By applying this method, the data consolidation steps can generate more accurate time-series datasets from available data pool. This can consequently increase the reliability of e-waste estimates compared to the approach without data processing. A case study in the Netherlands is used to apply the advanced IOA model. As a result, for the first time ever, complete datasets of all three variables for estimating all types of e-waste have been obtained. The result of this study also demonstrates significant disparity between various estimation models, arising from the use of data under different conditions. It shows the importance of applying multivariate approach and multiple sources to improve data quality for modelling, specifically using appropriate time-varying lifespan parameters. Following the case study, a roadmap with a procedural guideline is provided to enhance e-waste

Enhancing e-waste estimates: Improving data quality by multivariate Input–Output Analysis

International Nuclear Information System (INIS)

Wang, Feng; Huisman, Jaco; Stevels, Ab; Baldé, Cornelis Peter

2013-01-01

Highlights: • A multivariate Input–Output Analysis method for e-waste estimates is proposed. • Applying multivariate analysis to consolidate data can enhance e-waste estimates. • We examine the influence of model selection and data quality on e-waste estimates. • Datasets of all e-waste related variables in a Dutch case study have been provided. • Accurate modeling of time-variant lifespan distributions is critical for estimate. - Abstract: Waste electrical and electronic equipment (or e-waste) is one of the fastest growing waste streams, which encompasses a wide and increasing spectrum of products. Accurate estimation of e-waste generation is difficult, mainly due to lack of high quality data referred to market and socio-economic dynamics. This paper addresses how to enhance e-waste estimates by providing techniques to increase data quality. An advanced, flexible and multivariate Input–Output Analysis (IOA) method is proposed. It links all three pillars in IOA (product sales, stock and lifespan profiles) to construct mathematical relationships between various data points. By applying this method, the data consolidation steps can generate more accurate time-series datasets from available data pool. This can consequently increase the reliability of e-waste estimates compared to the approach without data processing. A case study in the Netherlands is used to apply the advanced IOA model. As a result, for the first time ever, complete datasets of all three variables for estimating all types of e-waste have been obtained. The result of this study also demonstrates significant disparity between various estimation models, arising from the use of data under different conditions. It shows the importance of applying multivariate approach and multiple sources to improve data quality for modelling, specifically using appropriate time-varying lifespan parameters. Following the case study, a roadmap with a procedural guideline is provided to enhance e-waste

Phytoextraction of chloride from a cement kiln dust (CKD) contaminated landfill with Phragmites australis.

Science.gov (United States)

McSorley, Kaitlin; Rutter, Allison; Cumming, Robert; Zeeb, Barbara A

2016-05-01

Cement kiln dust (CKD) is a globally produced by-product from cement manufacturing that is stockpiled or landfilled. Elevated concentrations of chloride pose toxic threats to plants and aquatic communities, as the anion is highly mobile in water and can leach into surrounding water sources. Re-vegetation and in situ phytoextraction of chloride from a CKD landfill in Bath, ON, Canada, was investigated with the resident invasive species Phragmites australis (haplotype M). Existing stands of P. australis were transplanted from the perimeter of the site into the highest areas of contamination (5.9×10(3)μg/g). Accumulation in the shoots of P. australis was quantified over one growing season by collecting samples from the site on a bi-weekly basis and analyzing for chloride. Concentrations decreased significantly from early May (24±2.2×10(3)μg/g) until mid-June (15±2.5×10(3)μg/g), and then remained stable from June to August. Shoot chloride accumulation was not significantly affected by water level fluctuations at the site, however elevated potassium concentrations in the soil may have contributed to uptake. Based on shoot chloride accumulation and total biomass, it was determined that phytoextraction from the CKD landfill can remove 65±4kg/km(2) of chloride per season. Based on this extraction rate, removal of chloride present in the highly contaminated top 10cm of soil can be achieved in 3-9years. This is the first study to apply phytotechnologies at a CKD landfill, and to successfully demonstrate in situ phytoextraction of chloride. Copyright © 2015 Elsevier Ltd. All rights reserved.

Enhancement of Biogas Production from Bakery Waste by Pseudomonas aeruginosa

OpenAIRE

S. Potivichayanon; T. Sungmon; W. Chaikongmao; S. Kamvanin

2011-01-01

Production of biogas from bakery waste was enhanced by additional bacterial cell. This study was divided into 2 steps. First step, grease waste from bakery industry-s grease trap was initially degraded by Pseudomonas aeruginosa. The concentration of byproduct, especially glycerol, was determined and found that glycerol concentration increased from 12.83% to 48.10%. Secondary step, 3 biodigesters were set up in 3 different substrates: non-degraded waste as substrate in fir...

Survival of introduced phosphate-solubilizing bacteria (PSB) and their impact on microbial community structure during the phytoextraction of Cd-contaminated soil.

Science.gov (United States)

Jeong, Seulki; Moon, Hee Sun; Shin, Doyun; Nam, Kyoungphile

2013-12-15

This study was conducted to investigate whether or not phosphate-solubilizing bacteria (PSB) as a kind of plant growth promoting rhizobacteria enhance the uptake of Cd by plants. In addition, the effect of PSB augmentation during phytoextraction on the microbial community of indigenous soil bacteria was also studied. In the initial Cd-contaminated soil, the major phyla were Proteobacteria (35%), Actinobacteria (38%) and Firmicutes (8%). While Proteobacteria were dominant at the second and sixth week (41 and 54%, respectively) in inoculated soil, Firmicutes (mainly belonging to the Bacilli class-61%), dramatically increased in the eight-week soil. For the uninoculated soil, the proportion of α-Proteobacteria increased after eight weeks (32%). Interestingly, Actinobacteria class, which was originally present in the soil (37%), seemed to disappear during phytoremediation, irrespective of whether PSB was inoculated or not. Cluster analysis and Principal Component Analysis revealed that the microbial community of eight-week inoculated soil was completely separated from the other soil samples, due to the dramatic increase of Bacillus aryabhattai. These findings revealed that it took at least eight weeks for the inoculated Bacillus sp. to functionally adapt to the introduced soil, against competition with indigenous microorganisms in soil. An ecological understanding of interaction among augmented bacteria, plant and indigenous soil bacteria is needed, for proper management of phytoextraction. Copyright © 2013 Elsevier B.V. All rights reserved.

Citric acid enhanced the antioxidant defense system and chromium uptake by Lemna minor L. grown in hydroponics under Cr stress.

Science.gov (United States)

Sallah-Ud-Din, Rasham; Farid, Mujahid; Saeed, Rashid; Ali, Shafaqat; Rizwan, Muhammad; Tauqeer, Hafiz Muhammad; Bukhari, Syed Asad Hussain

2017-07-01

Phytoextraction is a cost-effective and eco-friendly technique for the removal of pollutants, mainly heavy metal(loids) especially from polluted water and metal-contaminated soils. The phytoextraction of heavy metals is, in general, limited due to the low availability of heavy metals in the growth medium. Organic chelators can help to improve the phytoextraction by increasing metal mobility and solubility in the growth medium. The present research was carried out to examine the possibility of citric acid (CA) in improving chromium (Cr) phytoextraction by Lemna minor (duckweed). For this purpose, healthy plants were collected from nearby marsh and grown in hydroponics under controlled conditions. Initial metal contents of both marsh water and plant were measured along with physico-chemical properties of the marsh water. Different concentrations of Cr and CA were applied in the hydroponics in different combinations after defined intervals. Continuous aeration was supplied and pH maintained at 6.5 ± 0.1. Results showed that increasing concentration of Cr significantly decreased the plant biomass, photosynthetic pigments, leaf area, and antioxidant enzyme activities (like catalase, ascorbate peroxidase, superoxide dismutase, peroxidase). Furthermore, Cr stress increased the Cr concentrations, electrolyte leakage, hydrogen peroxide, and malondialdehyde contents in plants. The addition of CA alleviated the Cr-induced toxicity in plants and further enhanced the Cr uptake and its accumulation in L. minor. The addition of CA enhanced the Cr concentration in L. minor by 6.10, 26.5, 20.5, and 20.2% at 0, 10, 100, and 200 μM Cr treatments, respectively, compared to the respective Cr treatments without CA. Overall, the results of the present study showed that CA addition may enhance the Cr accumulation and tolerance in L. minor by enhancing the plant growth and activities of antioxidant enzymes.

The EDTA effect on phytoextraction of single and combined metals-contaminated soils using rainbow pink (Dianthus chinensis).

Science.gov (United States)

Lai, Hung-Yu; Chen, Zueng-Sang

2005-08-01

rainbow pink shoots. The proposed method worked especially well for Pb (p<0.05). The application of 2 mmol EDTA kg(-1) might too low to enhance the phytoextraction effect when used in silty clay soils.

Potential for phytoextraction of copper, lead, and zinc by rice (Oryza sativa L.), soybean (Glycine max [L.] Merr.), and maize (Zea mays L.).

Science.gov (United States)

Murakami, Masaharu; Ae, Noriharu

2009-03-15

Phytoextraction by hyperaccumulators has been proposed for decreasing toxic-metal concentrations of contaminated soils. However, hyperaccumulators have several shortcomings to introduce these species into Asian Monsoon's agricultural fields contaminated with low to moderate toxic-metals. To evaluate the phytoextraction potential, maize (Gold Dent), soybean (Enrei and Suzuyutaka), and rice (Nipponbare and Milyang 23) were pot-grown under aerobic soil conditions for 60d on the Andosol or Fluvisol with low to moderate copper (Cu), lead (Pb), and zinc (Zn) contamination. After 2 months cultivation, the Gold Dent maize and Milyang 23 rice shoots took up 20.2-29.5% and 18.5-20.2% of the 0.1molL(-1) HCl-extractable Cu, 10.0-37.3% and 8.5-34.3% of the DTPA-extractable Cu, and 2.4-6.5% and 2.1-5.9% of the total Cu, respectively, in the two soils. Suzuyutaka soybean shoot took up 23.0-29.4% of the 0.1molL(-1) HCl-extractable Zn, 35.1-52.6% of the DTPA-extractable Zn, and 3.8-5.3% of the total Zn in the two soils. Therefore, there is a great potential for Cu phytoextraction by the Gold Dent maize and the Milyang 23 rice and for Zn phytoextraction by the Suzuyutaka soybean from paddy soils with low to moderate contamination under aerobic soil conditions.

Environmental assessment: Solid waste retrieval complex, enhanced radioactive and mixed waste storage facility, infrastructure upgrades, and central waste support complex, Hanford Site, Richland, Washington

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

The U.S. Department of Energy (DOE) needs to take action to: retrieve transuranic (TRU) waste because interim storage waste containers have exceeded their 20-year design life and could fail causing a radioactive release to the environment provide storage capacity for retrieved and newly generated TRU, Greater-than-Category 3 (GTC3), and mixed waste before treatment and/or shipment to the Waste Isolation Pilot Project (WIPP); and upgrade the infrastructure network in the 200 West Area to enhance operational efficiencies and reduce the cost of operating the Solid Waste Operations Complex. This proposed action would initiate the retrieval activities (Retrieval) from Trench 4C-T04 in the 200 West Area including the construction of support facilities necessary to carry out the retrieval operations. In addition, the proposed action includes the construction and operation of a facility (Enhanced Radioactive Mixed Waste Storage Facility) in the 200 West Area to store newly generated and the retrieved waste while it awaits shipment to a final disposal site. Also, Infrastructure Upgrades and a Central Waste Support Complex are necessary to support the Hanford Site`s centralized waste management area in the 200 West Area. The proposed action also includes mitigation for the loss of priority shrub-steppe habitat resulting from construction. The estimated total cost of the proposed action is $66 million.

Environmental assessment: Solid waste retrieval complex, enhanced radioactive and mixed waste storage facility, infrastructure upgrades, and central waste support complex, Hanford Site, Richland, Washington

International Nuclear Information System (INIS)

1995-09-01

The U.S. Department of Energy (DOE) needs to take action to: retrieve transuranic (TRU) waste because interim storage waste containers have exceeded their 20-year design life and could fail causing a radioactive release to the environment provide storage capacity for retrieved and newly generated TRU, Greater-than-Category 3 (GTC3), and mixed waste before treatment and/or shipment to the Waste Isolation Pilot Project (WIPP); and upgrade the infrastructure network in the 200 West Area to enhance operational efficiencies and reduce the cost of operating the Solid Waste Operations Complex. This proposed action would initiate the retrieval activities (Retrieval) from Trench 4C-T04 in the 200 West Area including the construction of support facilities necessary to carry out the retrieval operations. In addition, the proposed action includes the construction and operation of a facility (Enhanced Radioactive Mixed Waste Storage Facility) in the 200 West Area to store newly generated and the retrieved waste while it awaits shipment to a final disposal site. Also, Infrastructure Upgrades and a Central Waste Support Complex are necessary to support the Hanford Site's centralized waste management area in the 200 West Area. The proposed action also includes mitigation for the loss of priority shrub-steppe habitat resulting from construction. The estimated total cost of the proposed action is $66 million

Phytoextraction with Brassica napus L.: A tool for sustainable management of heavy metal contaminated soils.

NARCIS (Netherlands)

Grispen, V.M.J.; Nelissen, H.J.M.; Verkleij, J.A.C.

2006-01-01

Phytoextraction is a promising tool to extract metals from contaminated soils and Brassica napus L. seems to be a possible candidate species for this purpose. To select accessions with the ability to accumulate cadmium, hydroponically grown 21 day old seedlings of 77 B. napus L. accessions were

Evaluation of phytoextracting cadmium and lead by sunflower, ricinus, alfalfa and mustard in hydroponic culture.

Science.gov (United States)

Zhi-xin, Niu; Sun, Li-na; Sun, Tie-heng; Li, Yu-shuang; Wang, Hong

2007-01-01

Soil contaminated with heavy metals cadmium (Cd) and lead (Pb) is hard to be remediated. Phytoremediation may be a feasible method to remove toxic metals from soil, but there are few suitable plants which can hyperaccumulate metals. In this study, Cd and Pb accumulation by four plants including sunflower (Helianthus annuus L.), mustard (Brassica juncea L.), alfalfa (Medicago sativa L.), ricinus (Ricinus communis L.) in hydroponic cultures was compared. Results showed that these plants could phytoextract heavy metals, the ability of accumulation differed with species, concentrations and categories of heavy metals. Values of BCF (bioconcentration factor) and TF (translocation factor) indicated that four species had dissimilar abilities of phytoextraction and transportation of heavy metals. Changes on the biomass of plants, pH and Eh at different treatments revealed that these four plants had distinct responses to Cd and Pb in cultures. Measurements should be taken to improve the phytoremediation of sites contaminated with heavy metals, such as pH and Eh regulations, and so forth.

Phytoextraction of 55-year-old wastewater-irrigated soil in a Zn-Pb mine district: effect of plant species and chelators.

Science.gov (United States)

Tai, YiPing; Yang, YuFen; Li, ZhiAn; Yang, Yang; Wang, JiaXi; Zhuang, Ping; Zou, Bi

2017-07-16

Untreated water from mining sites spreads heavy metal contamination. The present study assessed the phytoextraction performance of heavy metal-accumulating plants and the effects of chemical chelators on cadmium (Cd), lead (Pb), zinc (Zn), and copper (Cu) removal from paddy fields that have been continuously irrigated with mining wastewater from mines for 55 years. Outdoor pot experiments showed that the total Pb, Zn, and Cd content was lower in the rhizosphere soil of Amaranthus hypochondriacus than in that of Sedum alfredii, Solanum nigrum, and Sorghum bicolor. The aboveground biomass (dry weight) and relative growth rate of A. hypochondriacus were significantly higher than that of the other three species (P phytoextraction effect.

Phytoscreening and phytoextraction of heavy metals at Danish polluted sites using willow and poplar trees

DEFF Research Database (Denmark)

Nielsen, Mette Algreen; Trapp, Stefan; Rein, Arno

2014-01-01

The main purpose of this study was to determine typical concentrations of heavy metals (HM) in wood from willows and poplars, in order to test the feasibility of phytoscreening and phytoextraction of HM. Samples were taken from one strongly, one moderately, and one slightly polluted site and from...

Effect of sugarcane vinasse and EDTA on cadmium phytoextraction by two saltbush plants.

Science.gov (United States)

Eissa, Mamdouh A

2016-05-01

Although the use of saltbush plants in metal phytoremediation is well known, there is little information about the impact of sugarcane vinasse (SCV) and EDTA on metal uptake. Heavily cadmium-polluted soil (38 mg kg(-1) Cd) was used in pot and incubation experiments to investigate the Cd phytoextraction potential of wavy saltbush (Atriplex undulata) and quail saltbush (Atriplex lentiformis). EDTA at rates of 3, 6, and 10 mM kg(-1) soil and SCV at rates of 7, 15, and 30 mL kg(-1) soil were added to the polluted soil. The application of EDTA significantly (P = 0.002) reduced the growth of saltbush plants; on the other hand, SCV improved the growth. Both EDTA and SCV increased the availability and root-to-shoot transfer of Cd. The plants of A. lentiformis grown on the soil amended with the highest rate of SCV were able to remove 20.4 % of the total soil Cd during a period of 9 months. Based on the obtained results, it may be concluded that A. lentiformis and sugarcane vinasse could be more effective in the phytoextraction of Cd from the polluted soils.

Phytoextraction with Brassica napus L.: A tool for sustainable management of heavy metal contaminated soils

International Nuclear Information System (INIS)

Grispen, Veerle M.J.; Nelissen, Hans J.M.; Verkleij, Jos A.C.

2006-01-01

Phytoextraction is a promising tool to extract metals from contaminated soils and Brassica napus L. seems to be a possible candidate species for this purpose. To select accessions with the ability to accumulate cadmium, hydroponically grown 21 day old seedlings of 77 B. napus L. accessions were exposed to 0.2 μM CdSO 4 for an additional 10 days. The effects of Cd on several parameters were quantified i.e.; shoot Cd concentration ([Cd] shoot ), total amount of Cd in shoots (Total Cd) and the shoot to root Cd concentration ratio (S/R ratio). Though generally natural variation was low for [Cd] shoot , Total Cd and S/R ratio, a number of accessions could be selected. Our results indicated that Total Cd and S/R ratio are independent parameters for Cd accumulation and translocation. The selected varieties were then tested in field experiments on two locations nearby metal smelters. The two locations differed in extractable soil Cd, Zn, Ca concentration and pH levels. On both locations B. napus L. accessions showed significant differences in [Cd] shoot and Total Cd. Furthermore we found significant correlations between Cd and Zn accumulation in shoots. There were site-specific effects with respect to Cd accumulation in the B. napus L. accessions, however, two accessions seem to perform equally well on both sites. The results of the field experiment suggest that certain B. napus L. accessions are suitable for phytoextraction of moderately heavy metal contaminated soils. - A screening for natural variation in Cd accumulated by 77 Brassica napus L. yielded candidate phytoextraction accessions for agricultural practice

Phytoextraction with Brassica napus L.: A tool for sustainable management of heavy metal contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Grispen, Veerle M.J. [Department of Ecology and Physiology of Plants, Vrije Universiteit, De Boelelaan 1085, NL-1081 HV Amsterdam (Netherlands); Nelissen, Hans J.M. [Department of Ecology and Physiology of Plants, Vrije Universiteit, De Boelelaan 1085, NL-1081 HV Amsterdam (Netherlands); Verkleij, Jos A.C. [Department of Ecology and Physiology of Plants, Vrije Universiteit, De Boelelaan 1085, NL-1081 HV Amsterdam (Netherlands)]. E-mail: jos.verkleij@falw.vu.nl

2006-11-15

Phytoextraction is a promising tool to extract metals from contaminated soils and Brassica napus L. seems to be a possible candidate species for this purpose. To select accessions with the ability to accumulate cadmium, hydroponically grown 21 day old seedlings of 77 B. napus L. accessions were exposed to 0.2 {mu}M CdSO{sub 4} for an additional 10 days. The effects of Cd on several parameters were quantified i.e.; shoot Cd concentration ([Cd]{sub shoot}), total amount of Cd in shoots (Total Cd) and the shoot to root Cd concentration ratio (S/R ratio). Though generally natural variation was low for [Cd]{sub shoot}, Total Cd and S/R ratio, a number of accessions could be selected. Our results indicated that Total Cd and S/R ratio are independent parameters for Cd accumulation and translocation. The selected varieties were then tested in field experiments on two locations nearby metal smelters. The two locations differed in extractable soil Cd, Zn, Ca concentration and pH levels. On both locations B. napus L. accessions showed significant differences in [Cd]{sub shoot} and Total Cd. Furthermore we found significant correlations between Cd and Zn accumulation in shoots. There were site-specific effects with respect to Cd accumulation in the B. napus L. accessions, however, two accessions seem to perform equally well on both sites. The results of the field experiment suggest that certain B. napus L. accessions are suitable for phytoextraction of moderately heavy metal contaminated soils. - A screening for natural variation in Cd accumulated by 77 Brassica napus L. yielded candidate phytoextraction accessions for agricultural practice.

Moessbauer, TEM/SAED and XRD investigation on waste dumps of the Valea lui Stan gold mines

Energy Technology Data Exchange (ETDEWEB)

Constantinescu, Serban Grigore, E-mail: sconst@infim.ro [National Institute of Materials Physics, Bucharest-Magurele (Romania); Udubasa, Sorin S.; Udubasa, Gheorghe [University of Bucharest, Fac. of Geology and Geophysics (Romania); Kuncser, Victor; Popescu-Pogrion, Nicoleta; Mercioniu, Ionel; Feder, Marcel [National Institute of Materials Physics, Bucharest-Magurele (Romania)

2012-03-15

The complementary investigation techniques, Moessbauer spectroscopy, transmission electron microscopy with selected area electron diffraction (TEM/SAED), X-ray diffraction (XRD) have been used to investigate the fate of the Valea lui Stan, Romania, gold-ore nanoscale-minerals during the long time of residence in the waste dumps. The preliminary investigations showed such waste dumps to contain significant amount of metals which cannot be identified by conventional methods. An intense research activity started up in order to evaluate the possibilities to recycle Valea lui Stan waste dumps and to recover metals by chemical or phytoextraction procedures. The waste dumps naturally show different mineral constituents with clay minerals as major phases, observed by XRD-technique. Although the waste dumps materials have whitish-yellowish colours, MOeSSBAUER technique evidences the presence of the finely dispersed iron bearing minerals. The authors are focusing to inspect and analyze Fe-compounds in the samples collected from Valea lui Stan's waste dumps in order to identify the magnetic phases by Moessbauer technique.

Detoxification of wood preserving waste under ambient, enhanced and chemical pretreatment conditions

Energy Technology Data Exchange (ETDEWEB)

Hong, M.S.; Brown, K.W.; Dale, B.E.; Donnelly, K.C.; He, L.Y.; Markiewicz, K.V. [Texas A and M Univ., College Station, TX (United States)

1994-12-31

Detoxification of pentachlorophenol-containing wood preserving waste was monitored under ambient, enhanced and chemical pretreatment conditions for genotoxicity and parent compound removal. Samples were collected throughout the treatment periods and sequentially extracted with dichloromethane and methanol with the Tecator Soxtec apparatus. The organic extracts were analyzed on GC/ECD and GC/MS. The extract mutagenic and genotoxic potentials were evaluated with and without metabolic activation with the Salmonella Microsomal and E. coli Prophage Induction assays. The Salmonella mutagenic responses of extracts from Weswood soil amended with wood preserving waste and treated under ambient conditions were 2.0, 34.6 and 2.4 times greater than the solvent control on days 0, 540 and 1,200 respectively. Organic extracts of soil amended with wood preserving waste and treated under enhanced conditions in a solid-phase rotating drum bioreactor had mutagenic potentials of 3.4, 4.9 and 3.5 on days 0, 14 and 30, respectively. Extracts from wood preserving waste sludge treated with potassium polyethylene glycol were shown to have mutagenic potentials of 2.8, 6.1 and 3.8 at 0, 10 and 30 minutes. The results indicate that the initial products of the wood preserving waste detoxification under all treatment conditions appear to have greater genotoxic potentials than the starting material. The results also suggest that a more rapid detoxification occurs under enhanced and chemical pretreatment conditions.

Laboratory tests for the phytoextraction of heavy metals from polluted harbor sediments using aquatic plants.

Science.gov (United States)

Mânzatu, Carmen; Nagy, Boldizsár; Ceccarini, Alessio; Iannelli, Renato; Giannarelli, Stefania; Majdik, Cornelia

2015-12-30

The aim of this study was to investigate the concentrations and pollution levels of heavy metals, organochlorine pesticides, and polycyclic aromatic hydrocarbons in marine sediments from the Leghorn Harbor (Italy) on the Mediterranean Sea. The phytoextraction capacity of three aquatic plants Salvinia natans, Vallisneria spiralis, and Cabomba aquatica was also tested in the removal of lead and copper, present in high concentration in these sediments. The average detectable concentrations of metals accumulated by the plants in the studied area were as follows: >3.328 ± 0.032 mg/kg dry weight (DW) of Pb and 2.641 ± 0.014 mg/kg DW of Cu for S. natans, >3.107 ± 0.034 g/kg DW for V. spiralis, and >2.400 ± 0.029 mg/kg DW for C. aquatica. The occurrence of pesticides was also analyzed in the sediment sample by gas chromatography coupled with mass spectrometry (GC/MS). Due to its metal and organic compound accumulation patterns, S. natans is a potential candidate in phytoextraction strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Enhanced bioleaching efficiency of metals from E-wastes driven by biochar

Energy Technology Data Exchange (ETDEWEB)

Wang, Shuhua; Zheng, Yue; Yan, Weifu; Chen, Lixiang [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China); University of Chinese Academy of Sciences, Beijing, 100049 (China); Dummi Mahadevan, Gurumurthy [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China); Zhao, Feng, E-mail: fzhao@iue.ac.cn [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China)

2016-12-15

Electronic wastes (E-wastes) contain a huge amount of valuable metals that are worth recovering. Bioleaching has attracted widespread attention as an environment-friendly and low-cost technology for the recycling of E-wastes. To avoid the disadvantages of being time-consuming or having a relatively low efficiency, biochar with redox activity was used to enhance bioleaching efficiency of metals from a basic E-waste (i.e., printed circuit boards in this study). The role of biochar was examined through three basic processes: Carbon-mediated, Sulfur-mediated and Iron-mediated bioleaching pathways. Although no obvious enhancement of bioleaching performance was observed in the C-mediated and S-mediated systems, Fe-mediated bioleaching was significantly promoted by the participation of biochar, and its leaching time was decreased by one-third compared with that of a biochar-free system. By mapping the dynamic concentration of Fe(II) and Cu(II), biochar was proved to facilitate the redox action between Fe(II) to Fe(III), which resulted in effective leaching of Cu. Two dominant functional species consisting of Alicyclobacillus spp. and Sulfobacillus spp. may cooperate in the Fe-mediated bioleaching system, and the ratio of these two species was regulated by biochar for enhancing the efficiency of bioleaching. Hence, this work provides a method to improve bioleaching efficiency with low-cost solid redox media.

Enhanced bioleaching efficiency of metals from E-wastes driven by biochar

International Nuclear Information System (INIS)

Wang, Shuhua; Zheng, Yue; Yan, Weifu; Chen, Lixiang; Dummi Mahadevan, Gurumurthy; Zhao, Feng

2016-01-01

Electronic wastes (E-wastes) contain a huge amount of valuable metals that are worth recovering. Bioleaching has attracted widespread attention as an environment-friendly and low-cost technology for the recycling of E-wastes. To avoid the disadvantages of being time-consuming or having a relatively low efficiency, biochar with redox activity was used to enhance bioleaching efficiency of metals from a basic E-waste (i.e., printed circuit boards in this study). The role of biochar was examined through three basic processes: Carbon-mediated, Sulfur-mediated and Iron-mediated bioleaching pathways. Although no obvious enhancement of bioleaching performance was observed in the C-mediated and S-mediated systems, Fe-mediated bioleaching was significantly promoted by the participation of biochar, and its leaching time was decreased by one-third compared with that of a biochar-free system. By mapping the dynamic concentration of Fe(II) and Cu(II), biochar was proved to facilitate the redox action between Fe(II) to Fe(III), which resulted in effective leaching of Cu. Two dominant functional species consisting of Alicyclobacillus spp. and Sulfobacillus spp. may cooperate in the Fe-mediated bioleaching system, and the ratio of these two species was regulated by biochar for enhancing the efficiency of bioleaching. Hence, this work provides a method to improve bioleaching efficiency with low-cost solid redox media.

Enhanced bioleaching efficiency of metals from E-wastes driven by biochar.

Science.gov (United States)

Wang, Shuhua; Zheng, Yue; Yan, Weifu; Chen, Lixiang; Dummi Mahadevan, Gurumurthy; Zhao, Feng

2016-12-15

Electronic wastes (E-wastes) contain a huge amount of valuable metals that are worth recovering. Bioleaching has attracted widespread attention as an environment-friendly and low-cost technology for the recycling of E-wastes. To avoid the disadvantages of being time-consuming or having a relatively low efficiency, biochar with redox activity was used to enhance bioleaching efficiency of metals from a basic E-waste (i.e., printed circuit boards in this study). The role of biochar was examined through three basic processes: Carbon-mediated, Sulfur-mediated and Iron-mediated bioleaching pathways. Although no obvious enhancement of bioleaching performance was observed in the C-mediated and S-mediated systems, Fe-mediated bioleaching was significantly promoted by the participation of biochar, and its leaching time was decreased by one-third compared with that of a biochar-free system. By mapping the dynamic concentration of Fe(II) and Cu(II), biochar was proved to facilitate the redox action between Fe(II) to Fe(III), which resulted in effective leaching of Cu. Two dominant functional species consisting of Alicyclobacillus spp. and Sulfobacillus spp. may cooperate in the Fe-mediated bioleaching system, and the ratio of these two species was regulated by biochar for enhancing the efficiency of bioleaching. Hence, this work provides a method to improve bioleaching efficiency with low-cost solid redox media. Copyright © 2016 Elsevier B.V. All rights reserved.

The hyperaccumulator Sedum plumbizincicola harbors metal-resistant endophytic bacteria that improve its phytoextraction capacity in multi-metal contaminated soil.

Science.gov (United States)

Ma, Ying; Oliveira, Rui S; Nai, Fengjiao; Rajkumar, Mani; Luo, Yongming; Rocha, Inês; Freitas, Helena

2015-06-01

Bacillus sp. E1S2 significantly enhanced the accumulation of Zn (18%) in plants compared with non-inoculated controls. The inoculated strains also showed high levels of colonization in rhizosphere and plant tissues. Results demonstrate the potential to improve phytoextraction of soils contaminated with multiple heavy metals by inoculating metal hyperaccumulating plants with their own selected functional endophytic bacterial strains. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phytoextraction potential of poplar (Populus alba L. var. pyramidalis Bunge) from calcareous agricultural soils contaminated by cadmium.

Science.gov (United States)

Hu, Yahu; Nan, Zhongren; Jin, Cheng; Wang, Ning; Luo, Huanzhang

2014-01-01

To investigate the phytoextraction potential of Populus alba L. var. pyramidalis Bunge for cadmium (Cd) contaminated calcareous soils, a concentration gradient experiment and a field sampling experiment (involving poplars of different ages) were conducted. The translocation factors for all experiments and treatments were greater than 1. The bioconcentration factor decreased from 2.37 to 0.25 with increasing soil Cd concentration in the concentration gradient experiment and generally decreased with stand age under field conditions. The Cd concentrations in P. pyramidalis organs decreased in the order of leaves > stems > roots. The shoot biomass production in the concentration gradient experiment was not significantly reduced with soil Cd concentrations up to or slightly over 50 mg kg(-1). The results show that the phytoextraction efficiency of P. pyramidalis depends on both the soil Cd concentration and the tree age. Populus pyramidalis is most suitable for remediation of slightly Cd contaminated calcareous soils through the combined harvest of stems and leaves under actual field conditions.

Phytoextraction and estimating optimal time for remediation of Cd-contaminated soils by Spinach

OpenAIRE

Somayyeh Eisazadeh Lazarjan; safoora asadi kapourchal; Mehdi Homaee

2016-01-01

The so-called phytoextraction in which hyperaccumulator plants are used to remediate the contaminated soils is proven to be an efficient method. The objective of this study was to investigate the capability of Spinach for phytoremediation of cadmium from Cd-contaminated soils and determine the efficiency extent of spinach for phytoremediation. For this purpose, a randomized block experimental design whit five treatments including 0, 15, 30, 60 and 120 mg Cd/ kg soil and three replications was...

Effects of Metal Phytoextraction Practices on the Indigenous Community of Arbuscular Mycorrhizal Fungi at a Metal-Contaminated Landfill

Science.gov (United States)

Pawlowska, Teresa E.; Chaney, Rufus L.; Chin, Mel; Charvat, Iris

2000-01-01

Phytoextraction involves use of plants to remove toxic metals from soil. We examined the effects of phytoextraction practices with three plant species (Silene vulgaris, Thlaspi caerulescens, and Zea mays) and a factorial variation of soil amendments (either an ammonium or nitrate source of nitrogen and the presence or absence of an elemental sulfur supplement) on arbuscular mycorrhizal (AM) fungi (Glomales, Zygomycetes) at a moderately metal-contaminated landfill located in St. Paul, Minn. Specifically, we tested whether the applied treatments affected the density of glomalean spores and AM root colonization in maize. Glomalean fungi from the landfill were grouped into two morphotypes characterized by either light-colored spores (LCS) or dark-colored spores (DCS). Dominant species of the LCS morphotype were Glomus mosseae and an unidentified Glomus sp., whereas the DCS morphotype was dominated by Glomus constrictum. The density of spores of the LCS morphotype from the phytoremediated area was lower than the density of these spores in the untreated landfill soil. Within the experimental area, spore density of the LCS morphotype in the rhizosphere of mycorrhizal maize was significantly higher than in rhizospheres of nonmycorrhizal S. vulgaris or T. caerulescens. Sulfur supplement increased vesicular root colonization in maize and exerted a negative effect on spore density in maize rhizosphere. We conclude that phytoextraction practices, e.g., the choice of plant species and soil amendments, may have a great impact on the quantity and species composition of glomalean propagules as well as on mycorrhiza functioning during long-term metal-remediation treatments. PMID:10831433

Combining phytoextraction and biochar addition improves soil biochemical properties in a soil contaminated with Cd.

Science.gov (United States)

Lu, Huanping; Li, Zhian; Fu, Shenglei; Méndez, Ana; Gascó, Gabriel; Paz-Ferreiro, Jorge

2015-01-01

The main goal of phytoremediation is to improve ecosystem functioning. Soil biochemical properties are considered as effective indicators of soil quality and are sensitive to various environmental stresses, including heavy metal contamination. The biochemical response in a soil contaminated with cadmium was tested after several treatments aimed to reduce heavy metal availability including liming, biochar addition and phytoextraction using Amaranthus tricolor L. Two biochars were added to the soil: eucalyptus pyrolysed at 600 °C (EB) and poultry litter at 400 °C (PLB). Two liming treatments were chosen with the aim of bringing soil pH to the same values as in the treatments EB and PLB. The properties studied included soil microbial biomass C, soil respiration and the activities of invertase, β-glucosidase, β-glucosaminidase, urease and phosphomonoesterase. Both phytoremediation and biochar addition improved soil biochemical properties, although results were enzyme specific. For biochar addition these changes were partly, but not exclusively, mediated by alterations in soil pH. A careful choice of biochar must be undertaken to optimize the remediation process from the point of view of metal phytoextraction and soil biological activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of heavy metal and edta application on plant growth and phyto-extraction potential of sorghum (sorghum bicolor)

International Nuclear Information System (INIS)

Bacaha, N.; Shamas, R.; Bakht, J.; Rafi, A.; Farhatullah, M.; Gillani, S.

2015-01-01

Pot experiment was conducted to evaluate the phyto-extraction capacity of heavy metals by Sorghum. Sorghum bicolor was grown in soil artificially contaminated with different concentrations of lead (300, 350 and 400 mg/kg), chromium (50, 100 and 150 mg/kg) and cadmium (100, 150 and 200 mg/kg). Five mM EDTA was applied, as chelating agent to the plants after 4 weeks of sowing. Plants were grown for a total of two months and fresh weight and dry weight of shoot and heavy metal accumulation were analyzed at six and eight weeks after sowing. The results revealed that application of cadmium, chromium and lead and EDTA adversely affected shoot length, fresh weight and dry weight of S. bicolor at both time intervals. Heavy metals uptake increased with the increment of heavy metal by S. bicolor species. Application of 5mM EDTA enhanced the uptake of heavy metal. (author)

PRISM [Power Reactor Inherently Safe Module] design concept enhances waste management

International Nuclear Information System (INIS)

Thompson, M.L.; Berglund, R.C.

1989-01-01

PRISM, a modular advanced liquid metal reactor (ALMR), has been designed conceptually by GE under the US Department of Energy sponsorship. The concept design and analyses have been primarily focused on passive safety and improved construction and operating costs. Significantly, the unique design of multiple modules and features of PRISM enhance waste management over conventional reactor systems. This paper provides an overview of PRISM of these enhancements. Inherent to the ALMR's, the sodium coolant precludes crud buildup on reactor surfaces and in components and waste for disposal. Preliminary evaluations indicate this fundamental feature results in factors of 2-4 less waste volume and 2-3 orders of magnitude less curies per megawatt-electric for ultimate disposal. For example, the tap designed for sodium cleanup is expected to be exchanged only once every thirty years. Also, inherent to ALMR's, burning waste actinides and selected fission products to preclude their accumulation and burial is very attractive. The hard neutron spectrum of ALMR burns the actinides efficiently and is not poisoned by the actinides and fission products. The modular design of PRISM components (and the fuel cycle equipment) permit replacement without expensive and potentially hazardous volume reduction. For example, the functional components of the reference electromagnetic pump and IHK can be removed intact for waste disposal. Although development of the reference metal fuel is not completed, it is estimated that (low-level) waste from recycle of the fuel will result in significantly less volume than would be generated by aqueous recycle of oxide fuel. 6 refs., 10 figs

The Effects of EDTA and H2SO4 on Phyto-extraction of Pb from contaminated Soils by Radish

Directory of Open Access Journals (Sweden)

T. Mansouri

2016-10-01

Full Text Available Introduction: Soil contamination by heavy metals is one of the most important environmental concerns in many parts of the world. The remediation of soil contaminated with heavy metals is necessary to prevent the entry of these metals into the human food chain. Phyto-extraction is an effective, cheap and environmental friendly method which uses plants for cleaning contaminated soils. The plants are used for phytoremediation should have high potential for heavy metals uptake and produce enormous amount of biomass. A major problem facing phyto-extraction method is the immobility of heavy metals in soils. Chemical phyto-extraction is a method in which different acids and chelating substances are used to enhance the mobility of heavy metals in soil and their uptake by plants. The aims of this study were: (a to determine the potential of radish to extract Pb from contaminated soils and (b to assess the effects of different soil amendment (EDTA and H2SO4 to enhance plant uptake of the heavy metal and (c to study the effects of different levels of soil Pb on radish growth and Pb concentrations of above and below ground parts of this plant. Materials and Methods: Soil samples were air dried and passed through a 2 mm sieve and analysed for some physico-chemical properties and then artificially contaminated with seven levels of lead (0, 200, 400, 600, 800 and 1000 mg/kg using Pb(NO32 salt and then planted radish. During the growth period of radish and after the initiation of root growth, the plants were treated with three levels of sulfuric acid (0, 750 and 1500 mg/kg or three levels of EDTA (0, 10 and 20 mg/kg through irrigation water. At the end of growth period, the above and below ground parts of the plants were harvested, washed, dried and digested using a mixture of HNO3, HCl, and H2O2. The concentrations of Pb, N, P and K in plant extracts were measured. Statistical analysis of data was performed using MSTATC software and comparison of means was

Potential for Phytoextraction of Cu by Sesamum indicum L. and Cyamopsis tetragonoloba L.: A Green Solution to Decontaminate Soil

Science.gov (United States)

Amin, Hira; Arain, Basir Ahmed; Abbasi, Muhammad Sadiq; Jahangir, Taj Muhammad; Amin, Farah

2018-05-01

Phytoextraction is a plant based-technique for removing toxic heavy metals from polluted soil. The experiment reported in this paper was undertaken to study the basic Cu phytoextraction potential of Sesamum indicum in comparison with Cyamopsis tetragonoloba for remediation of Cu contaminated soil in the framework of a pot-experiment. Plants were subjected to seven Cu concentrations (0, 25, 50, 100, 150, 200, and 300 mg kg-1 soil) for 12 weeks. The morphological (i.e. growth) and biochemical (i.e. chlorophyll) parameters of both the plant species were observed throughout the experimental period; the phytoextraction efficiency of S. indicum and C. tetragonoloba were also determined. Most growth parameters were reduced under high Cu stress. Our results shows that at low concentration (25 mg Cu kg-1) all the growth and biochemical parameters were increased but at elevated Cu concentrations, root length, shoot length, and biomass (fresh and dry) were all significantly decreased ( p soil was noted for all tested treatments. In this study, both plant species showed quite high Cu tolerance and accumulation efficiency, even though C. tetragonoloba have higher Cu accumulation and tolerance indices than that of S . indicum. At 300 mg Cu kg-1, the highest Cu concentration was found in the root (282.08 mg Cu kg-1) followed by leaf (105.78 mg Cu kg-1), stem (65.30 mg Cu kg-1), and pod (8.13 mg Cu kg-1) of S. indicum. In contrast, C. tetragonoloba had highest Cu concentration primarily in the root (158.45 mg Cu kg-1) followed by the stem (154.73 mg Cu kg-1), leaf (152.32 mg Cu kg-1), and pod (8.13 mg Cu kg-1). Considering rapid growth, high biomass, tolerance, accumulation efficiency, bioconcentration factor (BCF) > 1, bioaccumulation coefficient (BAC) > 1 and translocation factor (TF) > 1 established C. tetragonoloba as a potential candidate plant for the decontamination of slightly Cu-polluted soil where the growth of plants would not be impaired and the extraction of Cu could

Enhancing gold recovery from electronic waste via lixiviant metabolic engineering in Chromobacterium violaceum

Science.gov (United States)

Tay, Song Buck; Natarajan, Gayathri; Rahim, Muhammad Nadjad bin Abdul; Tan, Hwee Tong; Chung, Maxey Ching Ming; Ting, Yen Peng; Yew, Wen Shan

2013-01-01

Conventional leaching (extraction) methods for gold recovery from electronic waste involve the use of strong acids and pose considerable threat to the environment. The alternative use of bioleaching microbes for gold recovery is non-pollutive and relies on the secretion of a lixiviant or (bio)chemical such as cyanide for extraction of gold from electronic waste. However, widespread industrial use of bioleaching microbes has been constrained by the limited cyanogenic capabilities of lixiviant-producing microorganisms such as Chromobacterium violaceum. Here we show the construction of a metabolically-engineered strain of Chromobacterium violaceum that produces more (70%) cyanide lixiviant and recovers more than twice as much gold from electronic waste compared to wild-type bacteria. Comparative proteome analyses suggested the possibility of further enhancement in cyanogenesis through subsequent metabolic engineering. Our results demonstrated the utility of lixiviant metabolic engineering in the construction of enhanced bioleaching microbes for the bioleaching of precious metals from electronic waste. PMID:23868689

The application of biotechnology on the enhancing of biogas production from lignocellulosic waste.

Science.gov (United States)

Wei, Suzhen

2016-12-01

Anaerobic digestion of lignocellulosic waste is considered to be an efficient way to answer present-day energy crisis and environmental challenges. However, the recalcitrance of lignocellulosic material forms a major obstacle for obtaining maximum biogas production. The use of biological pretreatment and bioaugmentation for enhancing the performance of anaerobic digestion is quite recent and still needs to be investigated. This paper reviews the status and perspectives of recent studies on biotechnology concept and investigates its possible use for enhancing biogas production from lignocellulosic waste with main emphases on biological pretreatment and bioaugmentation techniques.

Validation of enhanced stabilization of municipal solid waste under controlled leachate recirculation using FTIR and XRD.

Science.gov (United States)

Sethi, Sapna; Kothiyal, N C; Nema, Arvind K

2012-07-01

Leachate recirculation at neutral PH accompanied with buffer/nutrients addition has been used successfully in earlier stabilization of municipal solid waste in bioreactor landfills. In the present study, efforts were made to enhance the stabilization rate of municipal solid waste (MSW) and organic solid waste (OSW) in simulated landfill bioreactors by controlling the pH of recirculated leachate towards slightly alkaline side in absence of additional buffer and nutrients addition. Enhanced stabilization in waste samples was monitored with the help of analytical tools like Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD). Predominance of bands assigned to inorganic compounds and comparatively lower intensities of bands for organic compounds in the FTIR spectra of waste samples degraded with leachate recirculation under controlled pH confirmed higher rate of biodegradation and mineralization of waste than the samples degraded without controlled leachate recirculation. XRD spectra also confirmed to a greater extent of mineralization in the waste samples degraded under leachate recirculation with controlled pH. Comparison of XRD spectra of two types of wastes pointed out higher degree of mineralization in organic solid waste as compared to municipal solid waste.

Heavy metal phytoextraction-natural and EDTA-assisted remediation of contaminated calcareous soils by sorghum and oat.

Science.gov (United States)

Mahmood-Ul-Hassan, Muhammad; Suthar, Vishandas; Ahmad, Rizwan; Yousra, Munazza

2017-10-30

The abilities of sorghum (Sorghum bicolor L.) and oat (Avena sativa L.) to take up heavy metals from soils amended with ethylenediaminetetraacetic acid (EDTA) were assessed under greenhouse conditions. Both plants were grown in two soils contaminated with heavy metals (Gujranwala-silty loam and Pacca-clay loam). The soils were treated with 0, 0.625, 1.25, and 2.5 mM EDTA kg -1 soil applied at both 45 and 60 days after sowing (DAS); the experiment was terminated at 75 DAS. Addition of EDTA significantly increased concentrations of Cd, Cr, and Pb in roots and shoots, and bio-concentration factors and phytoextraction rates were also increased. Post-harvest soil analysis showed that soluble fractions of metals were also increased significantly. The increase in Cd was ≈ 3-fold and Pb was ≈ 15-fold at the highest addition of EDTA in Gujranwala soil; in the Pacca soil, the increase was less. Similarly, other phytoremediation factors, such as metal translocation, bio-concentration factor, and phytoextraction, efficiency were also maximum when soils were treated with 2.5 mM EDTA kg -1 soil. The study demonstrated that sorghum was better than oat for phytoremediation.

Phytoscreening and phytoextraction of heavy metals at Danish polluted sites using willow and poplar trees.

Science.gov (United States)

Algreen, Mette; Trapp, Stefan; Rein, Arno

2014-01-01

The main purpose of this study was to determine typical concentrations of heavy metals (HM) in wood from willows and poplars, in order to test the feasibility of phytoscreening and phytoextraction of HM. Samples were taken from one strongly, one moderately, and one slightly polluted site and from three reference sites. Wood from both tree species had similar background concentrations at 0.5 mg kg(-1) for cadmium (Cd), 1.6 mg kg(-1) for copper (Cu), 0.3 mg kg(-1) for nickel (Ni), and 25 mg kg(-1) for zinc (Zn). Concentrations of chromium (Cr) and lead (Pb) were below or close to detection limit. Concentrations in wood from the highly polluted site were significantly elevated, compared to references, in particular for willow. The conclusion from these results is that tree coring could be used successfully to identify strongly heavy metal-polluted soil for Cd, Cu, Ni, Zn, and that willow trees were superior to poplars, except when screening for Ni. Phytoextraction of HMs was quantified from measured concentration in wood at the most polluted site. Extraction efficiencies were best for willows and Cd, but below 0.5% over 10 years, and below 1‰ in 10 years for all other HMs.

Electromagnetic field pretreatment of Sinapis alba seeds improved cadmium phytoextraction.

Science.gov (United States)

Bulak, Piotr; Lata, Lesia; Plak, Andrzej; Wiącek, Dariusz; Strobel, Wacław; Walkiewicz, Anna; Pietruszewski, Stanisław; Bieganowski, Andrzej

2018-03-21

It was hypothesized that electromagnetic field (EMF) pretreatment of white mustard (Sinapis alba L.) seeds could increase the accumulation of non-essential, pollutant heavy metals such as cadmium (Cd) in shoots. Seeds of white mustard were treated with either 60 or 120 mT of alternating EMF (50 Hz) for 1 minute and then grown in a Petri dish in the presence of Cd, in comparison to the control (seeds grown without EMF pretreatment). Biomass production and content of calcium (Ca) and Cd in seedling shoots were measured. The Cd content in shoots from the EMF-treated seeds was higher in both variants than in the control (by 73% and 78%, respectively; p phytoextraction, but more research is needed.

Retrieval process development and enhancements waste simulant compositions and defensibility

International Nuclear Information System (INIS)

Powell, M.R.; Golcar, G.R.; Geeting, J.G.H.

1997-09-01

The purpose of this report is to document the physical waste simulant development efforts of the EM-50 Tanks Focus Area at the Hanford Site. Waste simulants are used in the testing and development of waste treatment and handling processes because performing such tests using actual tank waste is hazardous and prohibitively expensive. This document addresses the simulant development work that supports the testing of waste retrieval processes using simulants that mimic certain key physical properties of the tank waste. Development and testing of chemical simulants are described elsewhere. This work was funded through the EM-50 Tanks Focus Area as part of the Retrieval Process Development and Enhancements (RPD ampersand E) Project at the Pacific Northwest National Laboratory (PNNL). The mission of RPD ampersand E is to understand retrieval processes, including emerging and existing processes, gather performance data on those processes, and relate the data to specific tank problems to provide end users with the requisite technical bases to make retrieval and closure decisions. Physical simulants are prepared using relatively nonhazardous and inexpensive materials rather than the chemicals known to be in tank waste. Consequently, only some of the waste properties are matched by the simulant. Deciding which properties need to be matched and which do not requires a detailed knowledge of the physics of the process to be tested using the simulant. Developing this knowledge requires reviews of available literature, consultation with experts, and parametric tests. Once the relevant properties are identified, waste characterization data are reviewed to establish the target ranges for each property. Simulants are then developed that possess the desired ranges of properties

Remediation of sediment and water contaminated by copper in small-scaled constructed wetlands: effect of bioaugmentation and phytoextraction.

Science.gov (United States)

Huguenot, D; Bois, P; Cornu, J Y; Jezequel, K; Lollier, M; Lebeau, T

2015-01-01

The use of plants and microorganisms to mitigate sediment contaminated by copper was studied in microcosms that mimic the functioning of a stormwater basin (SWB) connected to vineyard watershed. The impact of phytoremediation and bioaugmentation with siderophore-producing bacteria on the fate of Cu was studied in two contrasted (batch vs. semi-continuous) hydraulic regimes. The fate of copper was characterised following its discharge at the outlet of the microcosms, its pore water concentration in the sediment, the assessment of its bioaccessible fraction in the rhizosphere and the measurement of its content in plant tissues. Physico-chemical (pH, redox potential) and biological parameters (total heterotrophic bacteria) were also monitored. As expected, the results showed a clear impact of the hydraulic regime on the redox potential and thus on the pore water concentration of Cu. Copper in pore water was also dependent on the frequency of Cu-polluted water discharges. Repeated bioaugmentation increased the total heterotrophic microflora as well as the Cu bioaccessibility in the rhizosphere and increased the amount of Cu extracted by Phragmites australis by a factor of ~2. Sugar beet pulp, used as a filter to avoid copper flushing, retained 20% of outcoming Cu and led to an overall retention of Cu higher than 94% when arranged at the outlet of microcosms. Bioaugmentation clearly improved the phytoextraction rate of Cu in a small-scaled SWB designed to mimic the functioning of a full-size SWB connected to vineyard watershed. Highlights: Cu phytoextraction in constructed wetlands much depends on the hydraulic regime and on the frequency of Cu-polluted water discharges. Cu phytoextraction increases with time and plant density. Cu bioaccessibility can be increased by bioaugmentation with siderophore-producing bacteria.

Phytoextraction of cadmium by rice (Oryza sativa L.), soybean (Glycine max (L.) Merr.), and maize (Zea mays L.)

Energy Technology Data Exchange (ETDEWEB)

Murakami, M. [Department of Environmental Chemistry, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan)]. E-mail: simple@affrc.go.jp; Ae, N. [Department of Environmental Chemistry, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan)]. E-mail: aenoriha@kobe-u.ac.jp; Ishikawa, S. [Department of Environmental Chemistry, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan)]. E-mail: isatoru@niaes.affrc.go.jp

2007-01-15

Selecting a phytoextraction plant with high Cd-accumulating ability based on the plant's compatibility with mechanized cultivation techniques may yield more immediately practical results than selection based on high tolerance to Cd. Rice (Oryza sativa L., cv. Nipponbare and Milyang 23), soybean (Glycine max [L.] Merr., cv. Enrei and Suzuyutaka), and maize (Zea mays L., cv. Gold Dent) were grown on one Andosol and two Fluvisols with low concentration of Cd contamination ranging from 0.83 to 4.29 mg Cd kg{sup -1}, during 60 days in pots (550 mL) placed in a greenhouse. Shoot Cd uptake was as follows: Gold Dent < Enrei and Nipponbare < Suzuyutaka and Milyang 23. Several soil Cd fractions after Milyang 23 harvesting decreased most. Milyang 23 accumulated 10-15% of the total soil Cd in its shoot. The Milyang 23 rice is thus promising for phytoextraction of Cd from paddy soils with low contamination level. - Milyang 23 rice (Oryza sativa L.) accumulated 10-15% of the total soil Cd in its shoot.

Phytoextraction of cadmium by rice (Oryza sativa L.), soybean (Glycine max (L.) Merr.), and maize (Zea mays L.)

International Nuclear Information System (INIS)

Murakami, M.; Ae, N.; Ishikawa, S.

2007-01-01

Selecting a phytoextraction plant with high Cd-accumulating ability based on the plant's compatibility with mechanized cultivation techniques may yield more immediately practical results than selection based on high tolerance to Cd. Rice (Oryza sativa L., cv. Nipponbare and Milyang 23), soybean (Glycine max [L.] Merr., cv. Enrei and Suzuyutaka), and maize (Zea mays L., cv. Gold Dent) were grown on one Andosol and two Fluvisols with low concentration of Cd contamination ranging from 0.83 to 4.29 mg Cd kg -1 , during 60 days in pots (550 mL) placed in a greenhouse. Shoot Cd uptake was as follows: Gold Dent < Enrei and Nipponbare < Suzuyutaka and Milyang 23. Several soil Cd fractions after Milyang 23 harvesting decreased most. Milyang 23 accumulated 10-15% of the total soil Cd in its shoot. The Milyang 23 rice is thus promising for phytoextraction of Cd from paddy soils with low contamination level. - Milyang 23 rice (Oryza sativa L.) accumulated 10-15% of the total soil Cd in its shoot

Collection of low-grade waste heat for enhanced energy harvesting

Energy Technology Data Exchange (ETDEWEB)

Dede, Ercan M., E-mail: eric.dede@tema.toyota.com; Schmalenberg, Paul; Wang, Chi-Ming; Zhou, Feng [Toyota Research Institute, Toyota Motor Engineering & Manufacturing North America, Ann Arbor, Michigan 48105 (United States); Nomura, Tsuyoshi [Toyota Central Research and Development Laboratories, Inc., Nagakute 480-1192 (Japan)

2016-05-15

Enhanced energy harvesting through the collection of low-grade waste heat is experimentally demonstrated. A structural optimization technique is exploited in the design of a thermal-composite substrate to guide and gather the heat emanating from multiple sources to a predetermined location. A thermoelectric generator is then applied at the selected focusing region to convert the resulting low-grade waste heat to electrical power. The thermal characteristics of the device are experimentally verified by direct temperature measurements of the system and numerically validated via heat conduction simulations. Electrical performance under natural and forced convection is measured, and in both cases, the device with optimized heat flow control plus energy harvesting demonstrates increased power generation when compared with a baseline waste heat recovery system. Electronics applications include energy scavenging for autonomously powered sensor networks or self-actuated devices.

Collection of low-grade waste heat for enhanced energy harvesting

International Nuclear Information System (INIS)

Dede, Ercan M.; Schmalenberg, Paul; Wang, Chi-Ming; Zhou, Feng; Nomura, Tsuyoshi

2016-01-01

Enhanced energy harvesting through the collection of low-grade waste heat is experimentally demonstrated. A structural optimization technique is exploited in the design of a thermal-composite substrate to guide and gather the heat emanating from multiple sources to a predetermined location. A thermoelectric generator is then applied at the selected focusing region to convert the resulting low-grade waste heat to electrical power. The thermal characteristics of the device are experimentally verified by direct temperature measurements of the system and numerically validated via heat conduction simulations. Electrical performance under natural and forced convection is measured, and in both cases, the device with optimized heat flow control plus energy harvesting demonstrates increased power generation when compared with a baseline waste heat recovery system. Electronics applications include energy scavenging for autonomously powered sensor networks or self-actuated devices.

Study on mechanisms of biosurfactant-enhanced composting technology for waste management

Energy Technology Data Exchange (ETDEWEB)

Zhang, B.Y.; Huang, G.H.; Chen, B.; Xi, B.D.; Maqsood, I. [Regina Univ., SK (Canada)

2003-07-01

Composting is increasingly being used for solid waste treatment. The efficiency of solid waste composting might be enhanced using biosurfactants produced by microbial activities. This study was conducted to characterize the effect of biosurfactant on solid waste biodegradation throughout the composting process. The method employed involves shredding solid waste, followed by a treatment in an 8-litre (L) batch reactor. Biosurfactant production was monitored daily along with characteristics and maturity degree. Surface tension and emulsification capacity were of particular concern. The measurement of indices such as humic acid carbon (CHA) and fulvic acid carbon (CFA) were used to evaluate the maturity degree. The results indicated that the highest level of biosurfactant concentration was achieved on the third day, and within two days, related emulsification capacity reached its peak. This study confirmed the presence of biosurfactants and their function during the composting process. 16 refs., 2 tabs., 4 figs.

Chemically assisted phytoextraction: A review of potential soil amendments for increasing plant uptake of heavy metals

OpenAIRE

Meers, Erik; Tack, Filip M. G.; Van Slycken, Stijn; Ruttens, Ann; Du Laing, Gijs; Vangronsveld, Jaco; Verloo, Marc G.

2008-01-01

The contamination of soils by trace metals has been an unfortunate sideeffect of industrialization. Some of these contaminants can interfere with vulnerable enduses of soil, such as agriculture or nature, already at relatively low levels of contamination. Reversely, conventional civil-technical soil-remediation techniques are too expensive to remediate extended areas of moderately contaminated soil. Phytoextraction has been proposed as a more economic complementary approach to deal with this ...

Aseptic hydroponics to assess rhamnolipid-Cd and rhamnolipid-Zn bioavailability for sunflower (Helianthus annuus): a phytoextraction mechanism study.

Science.gov (United States)

Wen, Jia; McLaughlin, Mike J; Stacey, Samuel P; Kirby, Jason K

2016-11-01

The availability of cadmium (Cd) and zinc (Zn) to sunflower (Helianthus annuus) was investigated in rhamnolipid- and ethylenediaminetetraacetic acid (EDTA)-buffered solutions in order to evaluate the influence of aqueous speciation of the metals on their uptake by the plant, in relation to predictions of uptake by the free ion activity model (FIAM). Free metal ion activity was estimated using the chemical equilibrium program MINTEQ or measured by Donnan dialysis. The uptake of Cd followed the FIAM for the EDTA-buffered solution at EDTA concentrations below 0.4 μM; for the rhamnolipid-buffered solution, the uptake of both metals in roots was not markedly affected by increasing rhamnolipid concentrations in solution. This suggests rhamnolipid enhanced metal accumulation in plant roots (per unit free metal in solution) possibly through formation and uptake of lipophilic complexes. The addition of normal Ca concentrations (low millimetre range) to the rhamnolipid uptake solutions reduced Cd accumulation in shoots by inhibiting Cd translocation, whereas it significantly increased Zn accumulation in shoots. This study confirms that although rhamnolipid could enhance accumulation of Cd in plants roots at low Ca supply, it is not suitable for Cd phytoextraction in contaminated soil environments where Ca concentrations in soil solution are orders of magnitude greater than those of Cd.

Enhancement of LNG plant propane cycle through waste heat powered absorption cooling

International Nuclear Information System (INIS)

Rodgers, P.; Mortazavi, A.; Eveloy, V.; Al-Hashimi, S.; Hwang, Y.; Radermacher, R.

2012-01-01

In liquefied natural gas (LNG) plants utilizing sea water for process cooling, both the efficiency and production capacity of the propane cycle decrease with increasing sea water temperature. To address this issue, several propane cycle enhancement approaches are investigated in this study, which require minimal modification of the existing plant configuration. These approaches rely on the use of gas turbine waste heat powered water/lithium bromide absorption cooling to either (i) subcool propane after the propane cycle condenser, or (ii) reduce propane cycle condensing pressure through pre-cooling of condenser cooling water. In the second approach, two alternative methods of pre-cooling condenser cooling water are considered, which consist of an open sea water loop, and a closed fresh water loop. In addition for all cases, three candidate absorption chiller configurations are evaluated, namely single-effect, double-effect, and cascaded double- and single-effect chillers. The thermodynamic performance of each propane cycle enhancement scheme, integrated in an actual LNG plant in the Persian Gulf, is evaluated using actual plant operating data. Subcooling propane after the propane cycle condenser is found to improve propane cycle total coefficient of performance (COP T ) and cooling capacity by 13% and 23%, respectively. The necessary cooling load could be provided by either a single-effect, double-effect or cascaded and single- and double-effect absorption refrigeration cycle recovering waste heat from a single gas turbine operated at full load. Reducing propane condensing pressure using a closed fresh water condenser cooling loop is found result in propane cycle COP T and cooling capacity enhancements of 63% and 22%, respectively, but would require substantially higher capital investment than for propane subcooling, due to higher cooling load and thus higher waste heat requirements. Considering the present trend of short process enhancement payback periods in the

Assessment of repeated harvests on mercury and arsenic phytoextraction in a multi-contaminated industrial soil

Directory of Open Access Journals (Sweden)

Martina Grifoni

2017-02-01

Full Text Available Mercury is widely distributed throughout the environment. In many contaminated soils other contaminants are present along with mercury; of these, arsenic is one of the most frequently found metals. In the presence of mixed contamination of this kind, remediation technologies must overcome many difficulties due to the different chemical characteristics of the various contaminants. In this study, repeated assisted phytoextraction cycles with Brassica juncea, were conducted on a laboratory scale to evaluate the removal efficiency of mercury and arsenic from a multi-contaminated industrial soil. The possibility of using only one additive, ammonium thiosulphate, to remove mercury and arsenic from co-contaminated soil simultaneously was also investigated. The thiosulfate addition greatly promoted the plant uptake of both contaminants, with an efficiency comparable to that of phosphate specifically used to mobilize specifically arsenic. Repeated additions of mobilizing agents increased metal availability in soil, promoted plant uptake and consequently increased the removal of contaminants in the studied soil. Repeated treatments with thiosulfate increased the concentration of mercury and arsenic in the Brassica juncea aerial part, but due to toxic effects of mercury that reduce biomass production, the total accumulation of both metals in plants tended to decrease at each subsequent re-growth.The use of a single additive to remove both contaminants simultaneously offers several new advantages to phytoextraction technology in terms of reducing cost and time.

Improvement of phytoextraction and antioxidative defense in Solanum nigrum L. under cadmium stress by application of cadmium-resistant strain and citric acid

Energy Technology Data Exchange (ETDEWEB)

Gao Yang, E-mail: gaoyang0898@sjtu.edu.cn [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai, 200240 (China); Key Laboratory of Soil and Water Conservation and Desertification Control, College of Soil and Water Conservation, Beijing Forestry University, Beijing 100083 (China); Miao Chiyuan [Department of Environmental Engineering, Peking University, Beijing, 100871 (China); Mao Liang [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai, 200240 (China); School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai, 200240 (China); Zhou Pei [School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai, 200240 (China); Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, Shanghai 200240 (China); Jin Zhiguo; Shi Wanjun [School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai, 200240 (China)

2010-09-15

Remediation of plant-microorganism-chelates synergy has been proposed as an effective remediation method for enhancing the removal efficiency of heavy metal. Manipulation of the antioxidative system increases plant tolerance, thereby potentially enhancing the uptake capacity to heavy metal. In this study, we investigated the possibility of improving the phytoextraction of Cd and the antioxidative defense of Solanum nigrum L. by application of a new isolated strain (Paecilomyces lilacinus NH1) (PLNH1) and citric acid (CA). The results showed that application of CA or PLNH1 significantly promoted S. nigrum's growth under Cd stress, but the synergistic effect of CA and PLNH1 on S. nigrum's growth was more obvious. The coexistence of CA and PLNH1 could enhance about 30% of Cd accumulation in different organs of S. nigrum compared to the treatment without the addition of CA and PLNH1, whereas single CA or PLNH1 added treatment only enhanced about 10-15% of Cd accumulation in different organs of S. nigrum. The antioxidative defense in S. nigrum under Cd stress was significantly improved as result of application of CA and PLNH1. The responses of antioxidative enzymes to Cd stress significantly decreased following application of CA and PLNH1, and the oxidative stress experienced by the plant due to Cd in the soil was significantly alleviated.

Improvement of phytoextraction and antioxidative defense in Solanum nigrum L. under cadmium stress by application of cadmium-resistant strain and citric acid

International Nuclear Information System (INIS)

Gao Yang; Miao Chiyuan; Mao Liang; Zhou Pei; Jin Zhiguo; Shi Wanjun

2010-01-01

Remediation of plant-microorganism-chelates synergy has been proposed as an effective remediation method for enhancing the removal efficiency of heavy metal. Manipulation of the antioxidative system increases plant tolerance, thereby potentially enhancing the uptake capacity to heavy metal. In this study, we investigated the possibility of improving the phytoextraction of Cd and the antioxidative defense of Solanum nigrum L. by application of a new isolated strain (Paecilomyces lilacinus NH1) (PLNH1) and citric acid (CA). The results showed that application of CA or PLNH1 significantly promoted S. nigrum's growth under Cd stress, but the synergistic effect of CA and PLNH1 on S. nigrum's growth was more obvious. The coexistence of CA and PLNH1 could enhance about 30% of Cd accumulation in different organs of S. nigrum compared to the treatment without the addition of CA and PLNH1, whereas single CA or PLNH1 added treatment only enhanced about 10-15% of Cd accumulation in different organs of S. nigrum. The antioxidative defense in S. nigrum under Cd stress was significantly improved as result of application of CA and PLNH1. The responses of antioxidative enzymes to Cd stress significantly decreased following application of CA and PLNH1, and the oxidative stress experienced by the plant due to Cd in the soil was significantly alleviated.

Enhanced biogas yield by thermo-alkali solubilization followed by co-digestion of intestine waste from slaughterhouse with food waste.

Science.gov (United States)

Porselvam, S; Soundara Vishal, N; Srinivasan, S V

2017-10-01

Intestine waste generated from slaughterhouse (IWS) is difficult to degrade in anaerobic process due to the presence of high protein and lipid contents. However, anaerobic co-digestion helps to increase the degradation of IWS by the addition of carbon-rich food waste (FW). To increase the biogas yield, thermo-alkali pretreatment may be more viable method for the anaerobic digestion of protein and lipid rich wastes. In the present study, Thermo-alkali pretreatment of intestine waste from slaughterhouse and food waste alone and mixing of IWS and FW with different ratios (1:1-1:3) on VS basis have been studied. To study the effect of Thermo-alkali pretreatment on solubilization of substrate, the substrate was mixed with alkali solutions (NaOH and KOH) at different concentrations of 1, 2, 3, 4 and 5% solutions. The results revealed that the maximum solubilization was observed to be 94.7% and 90.1% at KOH (1:3 and 5%) and NaOH (1:3 and 5%), respectively. Based on the study, enhancement in biogas yield by 16% (IWS), 11.5% (FW), 12.2% (1:1), 18.11% (1:2) and 22.5% (1:3) in KOH pretreated waste when compared with NaOH pretreated waste.

Evaluating phytoextraction efficiency of two high-biomass crops after soil amendment and inoculation with rhizobacterial strains.

Science.gov (United States)

Vanessa, Álvarez-López; Ángeles, Prieto-Fernández; Sergio, Roiloa; Beatriz, Rodríguez-Garrido; Rolf, Herzig; Markus, Puschenreiter; Susan, Kidd Petra

2017-03-01

We evaluated the effect of compost amendment and/or bacterial inoculants on the growth and metal accumulation of Salix caprea (clone BOKU 01 AT-004) and Nicotiana tabacum (in vitro-bred clone NBCu10-8). Soil was collected from an abandoned Pb/Zn mine and rhizobacterial inoculants were previously isolated from plants growing at the same site. Plants were grown in untreated or compost-amended (5% w/w) soil and were inoculated with five rhizobacterial strains. Non-inoculated plants were also established as a control. Compost addition increased the shoot DW yield of N. tabacum but not S. caprea, while it decreased soil metal availability and lowered shoot Cd/Zn concentrations in tobacco plants. Compost amendment enhanced the shoot Cd/Zn removal due to the growth promotion of N. tabacum or to the increase in metal concentration in S. caprea leaves. Bacterial inoculants increased photosynthetic efficiency (particularly in N. tabacum) and sometimes modified soil metal availability, but this did not lead to a significant increase in Cd/Zn removal. Compost amendment was more effective in improving the Cd and Zn phytoextraction efficiency than bioaugmentation.

Performance benefits of telerobotics and teleoperation - enhancements for an arm-based tank waste retrieval system

International Nuclear Information System (INIS)

Horschel, D.S.; Gibbons, P.W.; Draper, J.V.

1995-06-01

This report evaluates telerobotic and teleoperational arm-based retrieval systems that require advanced robotic controls. These systems will be deployed in waste retrieval activities in Hanford's Single Shell Tanks (SSTs). The report assumes that arm-based, retrieval systems will combine a teleoperational arm and control system enhanced by a number of advanced and telerobotic controls. The report describes many possible enhancements, spanning the full range of the control spectrum with the potential for technical maturation. The enhancements considered present a variety of choices and factors including: the enhancements to be included in the actual control system, safety, detailed task analyses, human factors, cost-benefit ratios, and availability and maturity of technology. Because the actual system will be designed by an offsite vendor, the procurement specifications must have the flexibility to allow bidders to propose a broad range of ideas, yet build in enough restrictions to filter out infeasible and undesirable approaches. At the same time they must allow selection of a technically promising proposal. Based on a preliminary analysis of the waste retrieval task, and considering factors such as operator limitations and the current state of robotics technology, the authors recommend a set of enhancements that will (1) allow the system to complete its waste retrieval mission, and (2) enable future upgrades in response to changing mission needs and technological advances

Performance benefits of telerobotics and teleoperation - enhancements for an arm-based tank waste retrieval system

Energy Technology Data Exchange (ETDEWEB)

Horschel, D.S. [Sandia National Labs., Albuquerque, NM (United States); Gibbons, P.W. [Westinghouse Hanford Co., Richland, WA (United States); Draper, J.V. [Oak Ridge National Lab., TN (United States)] [and others

1995-06-01

This report evaluates telerobotic and teleoperational arm-based retrieval systems that require advanced robotic controls. These systems will be deployed in waste retrieval activities in Hanford`s Single Shell Tanks (SSTs). The report assumes that arm-based, retrieval systems will combine a teleoperational arm and control system enhanced by a number of advanced and telerobotic controls. The report describes many possible enhancements, spanning the full range of the control spectrum with the potential for technical maturation. The enhancements considered present a variety of choices and factors including: the enhancements to be included in the actual control system, safety, detailed task analyses, human factors, cost-benefit ratios, and availability and maturity of technology. Because the actual system will be designed by an offsite vendor, the procurement specifications must have the flexibility to allow bidders to propose a broad range of ideas, yet build in enough restrictions to filter out infeasible and undesirable approaches. At the same time they must allow selection of a technically promising proposal. Based on a preliminary analysis of the waste retrieval task, and considering factors such as operator limitations and the current state of robotics technology, the authors recommend a set of enhancements that will (1) allow the system to complete its waste retrieval mission, and (2) enable future upgrades in response to changing mission needs and technological advances.

Enhancing anaerobic digestion performance of crude lipid in food waste by enzymatic pretreatment.

Science.gov (United States)

Meng, Ying; Luan, Fubo; Yuan, Hairong; Chen, Xue; Li, Xiujin

2017-01-01

Three lipases were applied to hydrolyze the floatable grease (FG) in the food waste for eliminating FG inhibition and enhancing digestion performance in anaerobic process. Lipase-I, Lipase-II, and Lipase-III obtained from different sources were used. Animal fat (AF) and vegetable oil (VO) are major crude lipids in Chinese food waste, therefore, applied as substrates for anaerobic digestion tests. The results showed that Lipase-I and Lipase-II were capable of obviously releasing long chain fatty acid in AF, VO, and FG when hydrolyzed in the conditions of 24h, 1000-1500μL and 40-50°C. Compared to the untreated controls, the biomethane production rate were increased by 80.8-157.7%, 26.9-53.8%, and 37.0-40.7% for AF, VO, and FG, respectively, and the digestion time was shortened by 10-40d. The finding suggests that pretreating lipids with appropriate lipase could be one of effective methods for enhancing anaerobic digestion of food waste rich in crude lipid. Copyright © 2016. Published by Elsevier Ltd.

Enhanced fermentable sugar production from kitchen waste using various pretreatments.

Science.gov (United States)

Hafid, Halimatun Saadiah; Rahman, Nor'Aini Abdul; Md Shah, Umi Kalsom; Baharudin, Azhari Samsu

2015-06-01

The kitchen waste fraction in municipal solid waste contains high organic matter particularly carbohydrate that can contribute to fermentable sugar production for subsequent conversion to bioethanol. This study was carried out to evaluate the influence of single and combination pretreatments of kitchen waste by liquid hot water, mild acid pretreatment of hydrochloric acid (HCl) and sulphuric acid (H2SO4) and enzymatic hydrolysis (glucoamylase). The maximum total fermentable sugar produced after combination pretreatment by 1.5% HCl and glucoamylase consisted of 93.25 g/L glucose, 0.542 g/L sucrose, 0.348 g/L maltose, and 0.321 g/L fructose. The glucose released by the combination pretreatment method was 0.79 g glucose/g KW equivalent to 79% of glucose conversion. The effects of the pre-treatment on kitchen waste indicated that the highest solubilization was 40% by the combination method of 1.5% HCl and glucoamylase. The best combination pre-treatment gave concentrations of lactic acid, acetic acid, and propionic acid of 11.74 g/L, 6.77 g/L, and 1.02 g/L, respectively. The decrease of aliphatic absorbance bands of polysaccharides at 2851 and 2923 cm(-1) and the increase on structures of carbonyl absorbance bands at 1600 cm(-1) reflects the progress of the kitchen waste hydrolysis to fermentable sugars. Overall, 1.5% HCl and glucoamylase treatment was the most profitable process as the minimum selling price of glucose was USD 0.101/g kitchen waste. Therefore, the combination pretreatment method was proposed to enhance the production of fermentable sugar, particularly glucose from kitchen waste as the feedstock for bioethanol production. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pretreatment of grass waste using combined ionizing radiation-acid treatment for enhancing fermentative hydrogen production.

Science.gov (United States)

Yang, Guang; Wang, Jianlong

2018-05-01

In this study, the combined ionizing radiation-acid pretreatment process was firstly applied to enhance hydrogen fermentation of grass waste. Results showed that the combined pretreatment synergistically enhanced hydrogen fermentation of grass waste. The SCOD and soluble polysaccharide contents of grass waste increased by 1.6 and 2.91 times after the combined pretreatment, respectively. SEM observation and crystallinity test showed the combined pretreatment effectively disrupted the grass structure. Owing to the more favorable substrate conditions, the hydrogen yield achieved 68 mL/g-dry grass added after the combined pretreatment, which was 161.5%, 112.5% and 28.3% higher than those from raw, ionizing radiation pretreated and acid pretreated grass waste, respectively. The VS removal also increased from 13.9% to 25.6% by the combined pretreatment. Microbial community analysis showed that the abundance of dominant hydrogen producing genus Clostridium sensu stricto 1 increased from 37.9% to 69.4% after the combined pretreatment, which contributed to more efficient hydrogen fermentation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluation the Efficiency of Six Sunflower Cultivars in Phytoextraction of Lead from a Pb-bearing Soil for Long Term

Directory of Open Access Journals (Sweden)

M.R. Naderi

2014-11-01

Full Text Available The right selection of an appropriate cultivar, which can be adapted with a particular pollutant and environmental conditions, is a crucial factor for a successful phytoremediation technology. Sunflower might be a suitable plant to remove the toxic metals from soil of polluted sites due to its rapid growth and high biomass production. In order to evaluate the efficiency of six sunflower cultivars in lead (Pb phytoextraction from a contaminated soil, an experiment was carried out using a completely randomized design with three replications in Research Station of Shahrekord University. Sunflower cultivars used in this experiment were Alestar, Serena, Sanburu, Hysun 33, Record and Euroflor. Results showed that there was a significant difference in shoot lead concentration, translocation factor and total lead harvested by shoot among sunflower cultivars at 1% probability level. Generally, due to translocation factor of all cultivars was less than 1, this can be stated that none of cultivars had the proper efficiency for extraction of lead from contaminated soil. However, high root lead concentration and low translocation factor of these cultivars show that efficiency of them for use in phytostabilization technique is more than phytoextraction technique.

Enhancement of glycerol production by zygosaccharomyces ruxii using strawberry wastes

International Nuclear Information System (INIS)

Meleigy, S.A; Taha, S.M.A.

2010-01-01

Glycerol is important industrial product that can be produced using osmophilic yeasts. In this study a local isolate of osmophilic yeast, zygosaccharomyces ruxii, was used for glycerol production from strawberry waste. The effects of some important parameters including glucose and urea concentrations, incubation temperature, initial ph and gamma irradiation were investigated. The optimum conditions for maximum glycerol production (126.8 g/l)by z. ruxii were occurred at 31 degree C and initial ph 5 in the presence of 250 g/l glucose and 3 g/l urea in the production medium . Under these optimizing fermentation parameters, enhancement of glycerol production (130 g/l) were recorded when the inoculum of z. ruxii was exposed to 0.25 kGy. also, the present results showed reduction in BOD 5 levels of fermented strawberry waste.

Assisted phytoextraction of heavy metals: compost and Trichoderma effects on giant reed (Arundo donax L. uptake and soil N-cycle microflora

Directory of Open Access Journals (Sweden)

Nunzio Fiorentino

2013-12-01

Full Text Available Little information is available as to the real effectiveness of the phytoextraction remediation technique, since laboratory experiments are still the most common way in which this is measured. Given this, an experiment on a cadmium-polluted soil was carried out in open field conditions in Southern Italy with the aim of assessing the growth and the phytoextraction potential of giant reed (Arundo donax L. Compost fertilisation and Trichoderma harzianum A6 inoculations were used to verify the possibility of increasing the metal uptake of the crop. Biomass yield of giant reed in the first growth season (average 12.8 Mg ha–1 was not affected by the Cd concentration in the soil and this increased significantly with compost fertilisation (13.8 Mg ha–1. Both compost fertilisation and T. harzianum inoculation increased cadmium uptake and translocation in leaves. Nitrifying bacteria was shown to be a useful tool to biomonitor soil quality. These results proved the suitability of the giant reed for assisted-phytoremedation with the use of compost fertilisation and T. harzianum.

Enhanced Waste Tank Level Model

Energy Technology Data Exchange (ETDEWEB)

Duignan, M.R.

1999-06-24

'With the increased sensitivity of waste-level measurements in the H-Area Tanks and with periods of isolation, when no mass transfer occurred for certain tanks, waste-level changes have been recorded with are unexplained.'

Phytoextraction, phytotransformation and rhizodegradation of ibuprofen associated with Typha angustifolia in a horizontal subsurface flow constructed wetland.

Science.gov (United States)

Li, Yifei; Zhang, Jiefeng; Zhu, Guibing; Liu, Yu; Wu, Bing; Ng, Wun Jern; Appan, Adhityan; Tan, Soon Keat

2016-10-01

Widespread occurrence of trace pharmaceutical residues in aquatic environments is of great concerns due to the potential chronic toxicity of certain pharmaceuticals including ibuprofen on aquatic organisms even at environmental levels. In this study, the phytoextraction, phytotransformation and rhizodegradation of ibuprofen associated with Typha angustifolia were investigated in a horizontal subsurface flow constructed wetland system. The experimental wetland system consisted of a planted bed with Typha angustifolia and an unplanted bed (control) to treat ibuprofen-loaded wastewater (∼107.2 μg L(-1)). Over a period of 342 days, ibuprofen was accumulated in leaf sheath and lamina tissues at a mean concentration of 160.7 ng g(-1), indicating the occurrence of the phytoextraction of ibuprofen. Root-uptake ibuprofen was partially transformed to ibuprofen carboxylic acid, 2-hydroxy ibuprofen and 1-hydroxy ibuprofen which were found to be 1374.9, 235.6 and 301.5 ng g(-1) in the sheath, respectively, while they were 1051.1, 693.6 and 178.7 ng g(-1) in the lamina. The findings from pyrosequencing analysis of the rhizosphere bacteria suggest that the Dechloromonas sp., the Clostridium sp. (e.g. Clostridium saccharobutylicum), the order Sphingobacteriales, and the Cytophaga sp. in the order Cytophagales were most probably responsible for the rhizodegradation of ibuprofen. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phytoextraction of potentially toxic elements by six tree species growing on hazardous mining sludge.

Science.gov (United States)

Mleczek, Mirosław; Goliński, Piotr; Krzesłowska, Magdalena; Gąsecka, Monika; Magdziak, Zuzanna; Rutkowski, Paweł; Budzyńska, Sylwia; Waliszewska, Bogusława; Kozubik, Tomisław; Karolewski, Zbigniew; Niedzielski, Przemysław

2017-10-01

The aim of the study was to compare the phytoextraction abilities of six tree species (Acer platanoides L., Acer pseudoplatanus L., Betula pendula Roth, Quercus robur L., Tilia cordata Miller, Ulmus laevis Pall.), cultivated on mining sludge contaminated with arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), thallium (Tl), and zinc (Zn). All six tree species were able to survive on such an unpromising substrate. However, A. platanoides and T. cordata seedlings grown on the polluted substrate showed significantly lower biomass than control plants (55.5 and 45.6%, respectively). As, Cd, Cu, Pb, and Tl predominantly accumulated in the roots of all the analyzed tree species with the following highest contents: 1616, 268, 2432, 547, and 856 mg kg -1 , respectively. Zn was predominantly localized in shoots with the highest content of 5801 and 5732 mg kg -1 for U. laevis and A. platanoides, respectively. A. platanoides was the most effective in Zn phytoextaction, with a bioconcentration factor (BCF) of 8.99 and a translocation factor (TF) of 1.5. Furthermore, with the exception of A. pseudoplatanus, the analyzed tree species showed a BCF > 1 for Tl, with the highest value for A. platanoides (1.41). However, the TF for this metal was lower than 1 in all the analyzed tree species. A. platanoides showed the highest BCF and a low TF and could, therefore, be a promising species for Tl phytostabilization. In the case of the other analyzed tree species, their potential for effective phytoextraction was markedly lower. Further studies on the use of A. platanoides in phytoremediation would be worth conducting.

Phytoextraction and phytostabilization potential of plants grown in the vicinity of heavy metal-contaminated soils: a case study at an industrial town site.

Science.gov (United States)

Lorestani, B; Yousefi, N; Cheraghi, M; Farmany, A

2013-12-01

With the development of urbanization and industrialization, soils have become increasingly polluted by heavy metals. Phytoremediation, an emerging cost-effective, nonintrusive, and aesthetically pleasing technology that uses the remarkable ability of plants to concentrate elements, can be potentially used to remediate metal-contaminated sites. In this research, two processes of phytoremediation (phytoextraction and phytostabilization) were surveyed in some plant species around an industrial town in the Hamedan Province in the central-western part of Iran. To this purpose, shoots and roots of the seven plant species and the associated soil samples were collected and analyzed by measuring Pb, Fe, Mn, Cu, and Zn concentrations using ICP-AES and then calculating the biological absorption coefficient, bioconcentration factor, and translocation factor parameters for each element. The obtained results showed that among the collected plants, Salsola soda is the most effective species for phytoextraction and phytostabilization and Cirsium arvense has the potential for phytostabilization of the measured heavy metals.

Significance of treated agrowaste residue and autochthonous inoculates (Arbuscular mycorrhizal fungi and Bacillus cereus) on bacterial community structure and phytoextraction to remediate soils contaminated with heavy metals.

Science.gov (United States)

Azcón, Rosario; Medina, Almudena; Roldán, Antonio; Biró, Borbála; Vivas, Astrid

2009-04-01

In this study, we analyzed the impact of treatments such as Aspergillus niger-treated sugar beet waste (SB), PO4(3-) fertilization and autochthonous inoculants [arbuscular mycorrhizal (AM) fungi and Bacillus cereus], on the bacterial community structure in a soils contaminated with heavy metals as well as, the effectiveness on plant growth (Trifolium repens). The inoculation with AM fungi in SB amended soil, increased plant growth similarly to PO4(3-) addition, and both treatments matched in P acquisition but bacterial biodiversity estimated by denaturing gradient gel electrophoresis of amplified 16S rDNA sequences, was more stimulated by the presence of the AM fungus than by PO4(3-) fertilization. The SB amendment plus AM inoculation increased the microbial diversity by 233% and also changed (by 215%) the structure of the bacterial community. The microbial inoculants and amendment used favoured plant growth and the phytoextraction process and concomitantly modified bacterial community in the rhizosphere; thus they can be used for remediation. Therefore, the understanding of such microbial ecological aspects is important for phytoremediation and the recovery of contaminated soils.

The impact of auxins used in assisted phytoextraction of metals from the contaminated environment on the alterations caused by lead(II) ions in the organization of model lipid membranes.

Science.gov (United States)

Hąc-Wydro, Katarzyna; Sroka, Aleksandra; Jabłońska, Klaudia

2016-07-01

Auxins are successfully used to improve phytoextraction efficiency of metal ions from the contaminated environment, however, the mechanism of their activity in this field is not explained. Auxins are known to exert various biochemical alterations in the plant membranes and cells, but their activity involves also direct interactions with lipids leading to changes in membrane organization. Following the suggestion that the auxins-induced modifications in membrane properties alleviate toxic effect of metal ions in this paper we have undertaken the comparative studies on the effect of metal ions and metal ions/auxins mixtures on model membrane systems. The experiments were done on lipid monolayers differing in their composition spread on water subphase and on Pb(2+), Indole-3-acetic acid (IAA), 1-Naphthaleneacetic acid (NAA) and Pb(2+)/IAA and Pb(2+)/NAA water solutions. The analysis of the collected data suggests that metal ions and auxins can change fluidity of the lipid systems and weaken the interactions between monolayer components. This manifested in the increase of the mean area per molecule and the excess area per molecule values for the films on Pb(2+), auxins as well as Pb(2+)/auxin solutions as compared to the values on pure water subphase. However, the presence of auxin in the mixture with lead(II) ions makes the alterations induced by sole metal ions weaker. This effect was more pronounced for the membranes of a higher packing. Thus it was proposed that auxins may enhance phytoextraction of metal ions by weakening their destabilizing effect on membrane. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of summer and winter harvesting on element phytoextraction efficiency of Salix and Populus clones planted on contaminated soil.

Science.gov (United States)

Kubátová, Pavla; Száková, Jiřina; Břendová, Kateřina; Kroulíková-Vondráčková, Stanislava; Mercl, Filip; Tlustoš, Pavel

2018-04-16

The clones of fast-growing trees (FGTs) were investigated for phytoextraction of soil contaminated with risk elements (REs), especially Cd, Pb, and Zn. As a main experimental factor, the potential effect of biomass harvesting time was assessed. The field experiment with two Salix clones (S1 - (Salix schwerinii × Salix viminalis) × S. viminalis, S2 - S. × smithiana) and two Populus clones (P1 - Populus maximowiczii × Populus nigra, P2 - P. nigra) was established in April 2009. Shoots of all clones were first harvested in February 2012. After two further growing seasons, the first half of the trees was harvested in September 2013 before leaf fall (summer harvest) and the second half in February 2014 (winter harvest). Remediation factors (RFs) for all clones and all REs (except Pb for clone S1) were higher in the summer harvest. The highest annual RFs for Cd and for Zn (1.34 and 0.67%, respectively) were found for clone S2 and were significantly higher than other clones. Although no increased mortality of trees harvested in the summer was detected in the following season, the effect of summer harvesting on the phytoextraction potential of FGTs clones should be investigated in long-term studies.

Valorisation of blueberry waste and use of compression to manufacture sustainable starch films with enhanced properties.

Science.gov (United States)

Luchese, Cláudia Leites; Uranga, Jone; Spada, Jordana Corralo; Tessaro, Isabel Cristina; de la Caba, Koro

2018-08-01

Blueberry waste from juice processing was valorised to develop starch films by compression moulding. The compression process resulted in hydrophobic films with water contact angles even higher than 100° for the films prepared with the highest blueberry waste content. Additionally, the film solubility was reduced by the incorporation of blueberry waste, regardless of the solution pH. These films also exhibited good barrier properties against UV light due to the aromatic compounds present in the blueberry waste. Furthermore, films showed a homogenous surface, although some pores appeared in the cross-section for the films with the highest blueberry waste content. Results highlighted the use of thermo-mechanical processes such as compression to manufacture sustainable films with enhanced properties through waste valorisation by the techniques actually employed at industrial scale. Copyright © 2018 Elsevier B.V. All rights reserved.

Cover crops influence soil microorganisms and phytoextraction of copper from a moderately contaminated vineyard.

Science.gov (United States)

Mackie, K A; Schmidt, H P; Müller, T; Kandeler, E

2014-12-01

We investigated the ability of summer (Avena sativa [oat], Trifolium incarnatum [crimson clover], Chenopodium [goosefoot]) and winter (Vicia villosa [hairy vetch], Secale Cereale L. [Rye], Brassica napus L. partim [rape]) cover crops, including a mixed species treatment, to extract copper from an organic vineyard soil in situ and the microbial communities that may support it. Clover had the highest copper content (14.3mgCukg(-1) DM). However, it was the amount of total biomass production that determined which species was most effective at overall copper removal per hectare. The winter crop rye produced significantly higher amounts of biomass (3532kgDMha(-1)) and, therefore, removed significantly higher amounts of copper (14,920mgCuha(-1)), despite less accumulation of copper in plant shoots. The maximum annual removal rate, a summation of best performing summer and winter crops, would be 0.033kgCuha(-1)y(-1). Due to this low annual extraction efficiency, which is less than the 6kgCuha(-1)y(-1) permitted for application, phytoextraction cannot be recommended as a general method of copper extraction from vineyards. Copper concentration did not influence aboveground or belowground properties, as indicated by sampling at two distances from the grapevine row with different soil copper concentrations. Soil microorganisms may have become tolerant to the copper levels at this site. Microbial biomass and soil enzyme activities (arylsulfatase and phosphatase) were instead driven by seasonal fluxes of resource pools. Gram+ bacteria were associated with high soil moisture, while fungi seemed to be driven by extractable carbon, which was linked to high plant biomass. There was no microbial group associated with the increased phytoextraction of copper. Moreover, treatment did not influence the abundance, activity or community structure of soil microorganisms. Copyright © 2014 Elsevier B.V. All rights reserved.

Distance-dependent varieties of microbial community structure and metabolic functions in the rhizosphere of Sedum alfredii Hance during phytoextraction of a cadmium-contaminated soil.

Science.gov (United States)

Yang, Wenhao; Zhang, Taoxiang; Lin, Sen; Ni, Wuzhong

2017-06-01

The recovery of microbial community and activities is crucial to the remediation of contaminated soils. Distance-dependent variations of microbial community composition and metabolic characteristics in the rhizospheric soil of hyperaccumulator during phytoextraction are poorly understood. A 12-month phytoextraction experiment with Sedum alfredii in a Cd-contaminated soil was conducted. A pre-stratified rhizobox was used for separating sub-layer rhizospheric (0-2, 2-4, 4-6, 6-8, 8-10 mm from the root mat)/bulk soils. Soil microbial structure and function were analyzed by phospholipid fatty acid (PLFA) and MicroResp™ methods. The concentrations of total and specified PLFA biomarkers and the utilization rates for the 14 substrates (organic carbon) in the 0-2-mm sub-layer rhizospheric soil were significantly increased, as well as decreased with the increase in the distance from the root mat. Microbial structure measured by the ratios of different groups of PLFAs such as fungal/bacterial, monounsaturated/saturated, ratios of Gram-positive to Gram-negative (GP/GN) bacterial, and cyclopropyl/monoenoic precursors and 19:0 cyclo/18:1ω7c were significantly changed in the 0-2-mm soil. The PLFA contents and substrate utilization rates were negatively correlated with pH and total, acid-soluble, and reducible fractions of Cd, while positively correlated with labile carbon. The dynamics of microbial community were likely due to root exudates and Cd uptake by S. alfredii. This study revealed the stimulations and gradient changes of rhizosphere microbial community through phytoextraction, as reduced Cd concentration, pH, and increased labile carbons are due to the microbial community responses.

Bacterially Induced Weathering of Ultramafic Rock and Its Implications for Phytoextraction

Science.gov (United States)

Kidd, Petra; Kuffner, Melanie; Prieto-Fernández, Ángeles; Hann, Stephan; Monterroso, Carmela; Sessitsch, Angela; Wenzel, Walter; Puschenreiter, Markus

2013-01-01

The bioavailability of metals in soil is often cited as a limiting factor of phytoextraction (or phytomining). Bacterial metabolites, such as organic acids, siderophores, or biosurfactants, have been shown to mobilize metals, and their use to improve metal extraction has been proposed. In this study, the weathering capacities of, and Ni mobilization by, bacterial strains were evaluated. Minimal medium containing ground ultramafic rock was inoculated with either of two Arthrobacter strains: LA44 (indole acetic acid [IAA] producer) or SBA82 (siderophore producer, PO4 solubilizer, and IAA producer). Trace elements and organic compounds were determined in aliquots taken at different time intervals after inoculation. Trace metal fractionation was carried out on the remaining rock at the end of the experiment. The results suggest that the strains act upon different mineral phases. LA44 is a more efficient Ni mobilizer, apparently solubilizing Ni associated with Mn oxides, and this appeared to be related to oxalate production. SBA82 also leads to release of Ni and Mn, albeit to a much lower extent. In this case, the concurrent mobilization of Fe and Si indicates preferential weathering of Fe oxides and serpentine minerals, possibly related to the siderophore production capacity of the strain. The same bacterial strains were tested in a soil-plant system: the Ni hyperaccumulator Alyssum serpyllifolium subsp. malacitanum was grown in ultramafic soil in a rhizobox system and inoculated with each bacterial strain. At harvest, biomass production and shoot Ni concentrations were higher in plants from inoculated pots than from noninoculated pots. Ni yield was significantly enhanced in plants inoculated with LA44. These results suggest that Ni-mobilizing inoculants could be useful for improving Ni uptake by hyperaccumulator plants. PMID:23793627

Enhanced On-Site Waste Management of Plasterboard in Construction Works: A Case Study in Spain

Directory of Open Access Journals (Sweden)

Ana Jiménez-Rivero

2017-03-01

Full Text Available On-site management of construction waste commonly determines its destination. In the case of plasterboard (PB, on-site segregation becomes crucial for closed-loop recycling. However, PB is commonly mixed with other wastes in Spain. In this context, the involvement of stakeholders that can contribute to reversing this current situation is needed. This paper analyzes on-site waste management of PB in Spain through a pilot study of a construction site, with the main objective of identifying best practices to increase waste prevention, waste minimization, and the recyclability of the waste. On-site visits and structured interviews were conducted. The results show five management stages: PB distribution (I; PB installation (II; Construction waste storage at the installation area (III; PB waste segregation at the installation area (IV and PB waste transfer to the PB container and storage (V. The proposed practices refer to each stage and include the merging of Stages III and IV. This measure would avoid the mixing of waste fractions in Stage III, maximizing the recyclability of PB. In addition, two requisites for achieving enhanced management are analyzed: ‘Training and commitment’ and ‘fulfilling the requirements established by the current regulation’. The results show that foremen adopted a more pessimistic attitude than installers towards a joint commitment for waste management. Moreover, not all supervisors valued the importance of a site waste management plan, regulated by the Royal Decree 105/2008 in Spain.

Lymphocytes from wasted mice express enhanced spontaneous and {gamma}-ray-induced apoptosis

Energy Technology Data Exchange (ETDEWEB)

Woloschak, G.E. [Argonne National Lab., IL (United States)]|[Loyola Univ. Medical Center, Maywood, IL (United States); Chang-Liu, Chin-Mei [Argonne National Lab., IL (United States); Chung, Jen; Libertin, C.R. [Loyola Univ. Medical Center, Maywood, IL (United States)

1993-09-01

Mice bearing the autosomal recessive mutation wasted (wst/wst) display a disease pattern including faulty repair of DNA damage in lymphocytes after radiation exposure, neurologic abnormalities, and immunodeficiency. Many of the features of this mouse model have suggested a premature or increased spontaneous frequency of apoptosis in thymocytes; past work has shown an inability to establish cultured T cell lines, an abnormally high death rate of stimulated T cells in culture, and an increased sensitivity of T cells to the killing effects of ionizing radiations in wst/wst mice relative to controls. The experiments reported here were designed to examine splenic and thymic lymphocytes from wasted and control mice for signs of early apoptosis. Our results revealed enhanced expression of Rp-8 mRNA (associated with apoptosis) in thymic lymphocytes and reduced expression in splenic lymphocytes of wst/wst mice relative to controls; expression of Rp-2 and Td-30 mRNA (induced during apoptosis) were not detectable in spleen or thymus. Higher spontaneous DNA fragmentation was observed in wasted mice than in controls; however, {gamma}-ray-induced DNA fragmentation peaked at a lower dose and occurred to a greater extent in wasted mice relative to controls. These results provide evidence for high spontaneous and {gamma}-ray-induced apoptosis in T cells of wasted mice as a mechanism underlying the observed lymphocyte and DNA repair abnormalities.

Carbon capture and biogas enhancement by carbon dioxide enrichment of anaerobic digesters treating sewage sludge or food waste.

Science.gov (United States)

Bajón Fernández, Y; Soares, A; Villa, R; Vale, P; Cartmell, E

2014-05-01

The increasing concentration of carbon dioxide (CO2) in the atmosphere and the stringent greenhouse gases (GHG) reduction targets, require the development of CO2 sequestration technologies applicable for the waste and wastewater sector. This study addressed the reduction of CO2 emissions and enhancement of biogas production associated with CO2 enrichment of anaerobic digesters (ADs). The benefits of CO2 enrichment were examined by injecting CO2 at 0, 0.3, 0.6 and 0.9 M fractions into batch ADs treating food waste or sewage sludge. Daily specific methane (CH4) production increased 11-16% for food waste and 96-138% for sewage sludge over the first 24h. Potential CO2 reductions of 8-34% for sewage sludge and 3-11% for food waste were estimated. The capacity of ADs to utilise additional CO2 was demonstrated, which could provide a potential solution for onsite sequestration of CO2 streams while enhancing renewable energy production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Phytoremediation modelling - phytoextraction of 137Cs, 133Ba, and 90Sr from liquid media and artificially contaminated soil

International Nuclear Information System (INIS)

Smrcek, S.; Masnerova, G.

2002-01-01

The phytoremediation model based on experiments with plants cultivated in vitro in media supplemented with radionuclide salts was investigated. The plant species Brassica napus, Sinapis alba, Helianthus annuus, Zea mays and Pisum sativum were cultivated on the Murashige-Skoog basal salt mixture enriched with salts of 137 Cs, 133 Ba, and 90 Sr in aseptic conditions. The time-dependent radioactivity decrease in the medium was determined using LSC, and the phytoextraction curves were plotted. Radioactivity in the plant roots and shoots was measured and the efficiency of phytoextraction and the distribution between the roots and shoots as a measure of radionuclide transport in the plant tissues were calculated for each of the plants used. Cultivation experiments were also performed on artificially contaminated soil. Seeds of the plants were placed into contaminated soil and cultivated for 2 months in conditions similar to those of the in vitro experiments. The extracted radioactivity and distribution between roots and shoots were determined. The in vitro experiments simulated extraction of the radionuclide salt from solution analogously to real extraction from the soil solution, while the processes occurring in the rhizosphere were eliminated. The phytoextraction efficiency in terms of the percentage of the starting radioactivity ranged from 12 to 31 % for 90 Sr, 8 to 24% for 137 Cs, and 12 to 17 % for 133 Ba in a cultivation cycle. The root/shoot radioactivity ratios demonstrate that the plant species used may be suitable for real phytoremediation. The experiments in which the plants were cultivated from seeds in artificial contaminated substrate showed that the ability of roots to extract radionuclide salts from their environment remains unchanged. The relative efficiency values were lower than for the extraction from solutions (3 to 11.5 % for 90 Sr, 1.5 to 4 % for 137 Cs, and 1 to 6.2 %, for 133 Ba), but in this process, the equilibrium between the soil particles

Solid Waste Information Tracking System (SWITS), Backlog Waste Modifications, Software Requirements Specification (SRS)

International Nuclear Information System (INIS)

Clark, R.E.

1995-01-01

Purpose of this document is to define the system requirements necessary to improve computer support for the WHC backlog waste business process through enhancements to the backlog waste function of the SWITS system. This SRS document covers enhancements to the SWITS system to support changes to the existing Backlog Waste screens including new data elements, label changes, and new pop-up screens. The pop-ups will allow the user to flag the processes that a waste container must have performed on it, and will provide history tracking of changes to data. A new screen will also be provided allowing Acceptable Services to perform mass updates to specific data in Backlog Waste table. The SWITS Backlog Waste enhancements in this document will support the project goals in WHC-SD-WM-003 and its Revision 1 (Radioactive Solid Waste Tracking System Conceptual Definition) for the control, tracing, and inventory management of waste as the packages are generated and moved through final disposal (cradle-to-grave)

Developing a Sustainability Assessment Model to Analyze China’s Municipal Solid Waste Management Enhancement Strategy

Directory of Open Access Journals (Sweden)

Hua Li

2015-01-01

Full Text Available This study develops a sustainability assessment model for analysis and decision-making of the impact of China’s municipal solid waste management enhancement strategy options based on three waste treatment scenarios: landfill disposal, waste-to-energy incineration, and a combination of a material recovery facility and composting. The model employs life cycle assessment, health risk assessment, and full cost accounting to evaluate the treatment scenarios regarding safeguarding public health, protecting the environment and conserving resources, and economic feasibility. The model then uses an analytic hierarchy process for an overall appraisal of sustainability. Results suggest that a combination of material recovery and composting is the most efficient option. The study results clarify sustainable attributes, suitable predications, evaluation modeling, and stakeholder involvement issues in solid waste management. The demonstration of the use of sustainability assessment model (SAM provides flexibility by allowing assessment for a municipal solid waste management (MSWM strategy on a case-by-case basis, taking into account site-specific factors, therefore it has the potential for flexible applications in different communities/regions.

Enhancement of biogas production at the municipal wastewater treatment plant by co-digestion with poultry industry waste

International Nuclear Information System (INIS)

Budych-Gorzna, Magdalena; Smoczynski, Marcin; Oleskowicz-Popiel, Piotr

2016-01-01

Highlights: • Laboratory and full-scale trials on co-digestion of sludge and poultry waste were performed. • Successful scaling-up of the results from laboratory to full-scale was accomplished. • Incremental addition of poultry waste to the full-scale anaerobic digesters did not cause any inhibition of the process. • WWTP energy dependency can be reduced significantly by co-digestion of sludge and external source of waste. - Abstract: Municipal wastewater treatment plants (WWTPs) are energy-intensive and thus cost-intensive facilities; therefore, it is crucial to increase energy production directly at the WWTP. Enhancement of biogas production by addition of external substrates is one of the solutions to increase energy self-sufficiency of the WWTPs with an additional benefit of cutting down the greenhouse gas emission. The main aim of the work was to investigate full utilization of the capacity of full-scale digesters at the municipal WWTP by addition of poultry industry waste. At first, laboratory trials were conducted in order to identify the most suitable dose for co-digestion with primary and waste activated sludge and finally, based on the achieved laboratory results, full-scale trials were carried out directly at the municipal WWTP. Poultry industrial waste yielded between 0.39 and 0.88 m 3 of methane per kg of volatile solids during laboratory trials, depending on the added concentration. During full-scale investigation yield of 0.81 m 3 /kg VS was achieved. Enhanced biogas production improved WWTP energy self-sufficiency bringing closer to the aim of increasing the share of self-produced energy up to 80%.

AFLP analysis and improved phytoextraction capacity of transgenic gshI-poplar clones (Populus x canescens L.) for copper in vitro

Energy Technology Data Exchange (ETDEWEB)

Gyulai, G. [St. Stephanus Univ., Dept. of Genetics and PB (Hungary); HAS-SIU Research Group for Molecular Plant Breeding (Hungary); IGER, Plas Gogerddan, Aberystwyth (United Kingdom); Humphreys, M.; Skoet, K.; Skoet, L.; Heywood, S.; Lovatt, A.; Roderick, H.; Abberton, M. [IGER, Plas Gogerddan, Aberystwyth (United Kingdom); Bittsanszky, A.; Kiss, J.; Szabo, Z. [St. Stephanus Univ., Dept. of Genetics and PB (Hungary); Gullner, G.; Koemives, T. [Plant Protection Inst., Hungarian Academy of Sciences, Budapest (Hungary); Radimszky, L. [Soil Science Inst., Hungarian Academy of Sciences, Budapest (Hungary); Rennenberg, H. [Albert-Ludwigs-Univ., Inst. fuer Forstbotanik und Baumphysiologie, Freiburg (Germany); Heszky, L. [St. Stephanus Univ., Dept. of Genetics and PB (Hungary); HAS-SIU Research Group for Molecular Plant Breeding (Hungary)

2005-04-01

Clone stability and in vitro phytoextraction capacity of vegetative clones of P. x canescens (2n = 4x = 38) including two transgenic clones (ggs11 and lgl6) were studied as in vitro leaf disc cultures. Presence of the gshI-transgene in the transformed clones was detected in PCR reactions using gshI-specific primers. Clone stability was determined by fAFLP (fluorescent amplified DNA fragment length polymorphism) analysis. In total, 682 AFLP fragments were identified generated by twelve selective primer pairs after EcoRI-MseI digestion. Four fragments generated by EcoAGT-MseCCC were different (99.4% genetic similarity) which proves an unexpectedly low bud mutation frequency in P. x canescens. For the study of phytoextraction capacity leaf discs (8 mm) were exposed to a concentration series of ZnSO{sub 4} (10{sup -1} to 10{sup -5} M) incubated for 21 days on aseptic tissue culture media WPM containing 1 {mu}M Cu. ZN{sup 2+} caused phytotoxicity only at high concentrations (10{sup -1} to 10{sup -2} M). The transgenic poplar cyt-ECS (ggs11) clone, as stimulated by the presence of Zn, showed elevated heavy metal (Cu) uptake as compared to the non-transformed clone. These results suggest that gshI-transgenic poplars may be suitable for phytoremediation of soils contaminated with zinc and copper. (orig.)

The influence of EDDS and EDTA on the uptake of heavy metals of Cd and Cu from soil with tobacco Nicotiana tabacum.

Science.gov (United States)

Evangelou, Michael W H; Bauer, Uwe; Ebel, Mathias; Schaeffer, Andreas

2007-06-01

Phytoextraction, the use of plants to extract contaminants from soils and groundwater, is a promising approach for cleaning up soils contaminated with heavy metals. In order to enhance phytoextraction the use of chelating agents has been proposed. This study aims to assess whether ethylene diamine disuccinate (EDDS), a biodegradable chelator, can be used for enhanced phytoextraction purposed, as an alternative to ethylene diamine tetraacetate (EDTA). EDDS revealed a higher toxicity to tobacco (Nicotiana tabacum) in comparison to EDTA, but no toxicity to microorganisms. The uptake of Cu was increased by the addition of EDTA and EDDS, while no increase was observed in the uptake of Cd. Both chelating agents showed a very low root to shoot translocation capability and the translocation factor was lower than the one of the control. Heavy metals where significantly more phytoavailable than in the control, even after harvesting, resulting in a high heavy metal leaching possibility, probably owing to a low biodegradation rate of EDDS. New seedlings which were transplanted into the EDDS treated pots 7d after the phytoextraction experiment, showed signs of necrosis and chlorosis, which resulted in a significantly lower biomass in comparison to the control. The seedlings on the EDTA treated pots showed no toxicity signs. Contrary to previous opinions the results of this study revealed the chelating agents EDTA and EDDS as unsuitable for enhanced phytoextraction using tobacco.

ENHANCED ANAEROBIC DIGESTION OF FOOD WASTE BY SUPPLEMENTING TRACE ELEMENTS: ROLE OF SELENIUM (VI AND IRON (II

Directory of Open Access Journals (Sweden)

Javkhlan eAriunbaatar

2016-02-01

Full Text Available This paper discusses the potential to enhance the anaerobic digestion of food waste FW by supplementing trace elements (Fe, Co, Ni, Zn, Mn, Cu, Se, and Mo individually as well as in cocktails. A series of batch experiments on the biomethane potential of synthetic food waste were performed with low (FW-A and high (FW-B trace element background concentrations prepared in, respectively, Delft (The Netherlands and Tampa (Florida, USA. The most effective trace elements for FW-A were Fe with an increase of 39.2 (± 0.6 % of biomethane production, followed by Se (34.1 ± 5.6 % increase, Ni (26.4 ± 0.2 % increase and Co (23.8 ± 0.2 % increase. For FW-B supplementing these trace elements did not result in enhancement of the biomethane production, except for Se. FW-B had a Se concentration of 1.3 (± 0. 5 µg/gTS, while it was below the detection limit for FW-A. Regardless of the FW source, Se resulted in 30 – 35% increase of biomethane production at a concentration range of 25-50 µg/L (0.32 – 0.63 µM. Volatile fatty acids analysis revealed that TE supplementation enhances their consumption, thus yielding a higher biomethane production. Moreover, additional experiments on sulfide inhibition showed the enhancing effects of trace elements on the anaerobic digestion of food waste were not related with sulfide toxicity, but with the enzymatic reactions and/or microbial biomass aggregation.

Phytoextraction of metals and rhizoremediation of PAHs in co-contaminated soil by co-planting of Sedum alfredii with ryegrass (Lolium perenne) or castor (Ricinus communis).

Science.gov (United States)

Wang, Kai; Huang, Huagang; Zhu, Zhiqiang; Li, Tingqiang; He, Zhenli; Yang, Xiaoe; Alva, Ashok

2013-01-01

A pot experiment was conducted to investigate the potential for phytoextraction of heavy metals and rhizoremediation of polycyclic aromatic hydrocarbons (PAHs) in co-contaminated soil by co-planting a cadmium/zinc (Cd/Zn) hyperaccumulator and lead (Pb) accumulator Sedum alfredii with ryegrass (Lolium perenne) or castor (Ricinus communis). Co-planting with castor decreased the shoot biomass of S. alfredii as compared to that in monoculture. Cadmium concentration in S. alfredii shoot significantly decreased when grown with ryegrass or castor as compared to that in monoculture. However, no reduction of Zn or Pb concentration in S. alfredii shoot was detected in co-planting treatments. Total removal of either Cd, Zn, or Pb by plants was similar across S. alfredii monoculture or co-planting with ryegrass or castor, except enhanced Pb removal in S. alfredii and ryegrass co-planting treatment. Co-planting of S. alfredii with ryegrass or castor significantly enhanced the pyrene and anthracene dissipation as compared to that in the bare soil or S. alfredii monoculture. This appears to be due to the increased soil microbial population and activities in both co-planting treatments. Co-planting of S. alfredii with ryegrass or castor provides a promising strategy to mitigate both metal and PAH contaminants from co-contaminated soils.

Heavy Metals Phytoextraction from the Polluted Soils of Zakamensk (Russia)

Science.gov (United States)

Ubugunov, V.; Dorzhonova, V.; Ubugunov, L.

2012-04-01

Mining and ore-dressing are one of the most serious causes of environment pollution. Last century in days of active industrialization in Russia a considerable quantity of mineral deposits has been developed. It was not given sufficient attention for ecological safety at that time. After an economic crisis connected with disorder of the USSR and a planned economy, a number of the enterprises became bankrupts and have stopped the activity. As a result the broken landscapes have not been recultivated everywhere, there were numerous wastes. The negative consequences were especially strongly manifested in areas with severe climatic conditions where environmental self-renewal occurred is slowed rather down. The degree of a waste toxicity also acted as the important factor. One of such situations has arisen in Zakamensk - an administrative center of Zakamensky area of Buryat Republic (Russia). Environmental problems of the town have arisen in connection with activity of town-forming enterprise - Dzhidinsky tungsten-molybdenum industrial complex. The enterprise has been organized in 1934 and functioned within 63 years till 1997. During enterprise operating time 3 deposits have been exploited and is created 2 large (more than 40 million tons) tails depository of technogenic sands (TS), located in immediate proximity (less than 1-2 km) from a town residential zone.Sand of tails are rather toxic, the average maintenance of heavy metals in them is (mg/kg): Cd - 42, Pb - 7500, Zn - 3160, Cu - 620, Ni - 34, Co - 44, Mn - 121, Cr - 70, Hg - 0,01, As - 13, Mo - 90. Due to the lack of knowledges on the toxicity of TS in the past century, they were actively used in the road and house construction, during the erection of dams. After scientific studies they were recommended for using as fertilizers. Besides anthropogenic sands movement, there was intensive dispersion of sand by means of water and wind erosion. As a result of natural migration sands got to the subordinated elements of

Potential for phytoextraction of PCBs from contaminated soils using weeds.

Science.gov (United States)

Ficko, Sarah A; Rutter, Allison; Zeeb, Barbara A

2010-07-15

A comprehensive investigation of the potential of twenty-seven different species of weeds to phytoextract polychlorinated biphenyls (PCBs) from contaminated soil was conducted at two field sites (Etobicoke and Lindsay) in southern Ontario, Canada. Soil concentrations were 31 microg/g and 4.7 microg/g at each site respectively. All species accumulated PCBs in their root and shoot tissues. Mean shoot concentrations at the two sites ranged from 0.42 microg/g for Chenopodium album to 35 microg/g for Vicia cracca (dry weight). Bioaccumulation factors (BAF=[PCB](plant tissue)/[PCB](mean soil)) at the two sites ranged from 0.08 for Cirsium vulgare to 1.1 for V. cracca. Maximum shoot extractions were 420 microg for Solidago canadensis at the Etobicoke site, and 120 microg for Chrysanthemum leucanthemum at the Lindsay site. When plant density was taken into account with a theoretical density value, seventeen species appeared to be able to extract a similar or greater quantity of PCBs into the shoot tissue than pumpkins (Curcurbita pepo ssp. pepo) which are known PCB accumulators. Therefore, some of these weed species are promising candidates for future phytoremediation studies. Crown Copyright 2010. Published by Elsevier B.V. All rights reserved.

The possibility of using 5-aminolevulinic acid in lead phytoextraction process

Directory of Open Access Journals (Sweden)

Zbigniew Jarosz

2013-04-01

Full Text Available Studies conducted in the greenhouse involving a sunflower (Helianthus annuus L. grown in medium containing 200 mg Pb ∙ dm -3 which were designed to evaluate the impact of foliar nutrition with 5-aminolevulinic acid (5-ALA on the chemical composition of sunflower in reference to possible use of this plant in the process of induced phytoextraction. The study revealed from 4.8% to 34.1% increase in aboveground matter of sunflower which was sprayed by 5-ALA solution at concentrations of 0.01-0.1 ppm in comparison with plants grown in a medium containing 200 mg Pb ∙ dm -3 with no 5-ALA spraying. The sunflower leaves sprayed by 5-ALA solution contained from 3.78% to 27.1% more lead in comparison to plants not sprayed by this agent. As well as remarkable decrease in lead content from 17.4 to 33.4% was recorded in the roots of sunflower sprayed by 5-ALA solution. The lead content in plant shoots was independent from foliar application of 5-aminolevulinic acid

Thermophilic anaerobic co-digestion of organic fraction of municipal solid waste (OFMSW) with food waste (FW): Enhancement of bio-hydrogen production.

Science.gov (United States)

Angeriz-Campoy, Rubén; Álvarez-Gallego, Carlos J; Romero-García, Luis I

2015-10-01

Bio-hydrogen production from dry thermophilic anaerobic co-digestion (55°C and 20% total solids) of organic fraction of municipal solid waste (OFMSW) and food waste (FW) was studied. OFMSW coming from mechanical-biological treatment plants (MBT plants) presents a low organic matter concentration. However, FW has a high organic matter content but several problems by accumulation of volatile fatty acids (VFAs) and system acidification. Tests were conducted using a mixture ratio of 80:20 (OFSMW:FW), to avoid the aforementioned problems. Different solid retention times (SRTs) - 6.6, 4.4, 2.4 and 1.9 days - were tested. It was noted that addition of food waste enhances the hydrogen production in all the SRTs tested. Best results were obtained at 1.9-day SRT. It was observed an increase from 0.64 to 2.51 L H2/L(reactor) day in hydrogen productivity when SRTs decrease from 6.6 to 1.9 days. However, the hydrogen yield increases slightly from 33.7 to 38 mL H2/gVS(added). Copyright © 2015 Elsevier Ltd. All rights reserved.

Economic assessment of flash co-pyrolysis of short rotation coppice and biopolymer waste streams.

Science.gov (United States)

Kuppens, T; Cornelissen, T; Carleer, R; Yperman, J; Schreurs, S; Jans, M; Thewys, T

2010-12-01

The disposal problem associated with phytoextraction of farmland polluted with heavy metals by means of willow requires a biomass conversion technique which meets both ecological and economical needs. Combustion and gasification of willow require special and costly flue gas treatment to avoid re-emission of the metals in the atmosphere, whereas flash pyrolysis mainly results in the production of (almost) metal free bio-oil with a relatively high water content. Flash co-pyrolysis of biomass and waste of biopolymers synergistically improves the characteristics of the pyrolysis process: e.g. reduction of the water content of the bio-oil, more bio-oil and less char production and an increase of the HHV of the oil. This research paper investigates the economic consequences of the synergistic effects of flash co-pyrolysis of 1:1 w/w ratio blends of willow and different biopolymer waste streams via cost-benefit analysis and Monte Carlo simulations taking into account uncertainties. In all cases economic opportunities of flash co-pyrolysis of biomass with biopolymer waste are improved compared to flash pyrolysis of pure willow. Of all the biopolymers under investigation, polyhydroxybutyrate (PHB) is the most promising, followed by Eastar, Biopearls, potato starch, polylactic acid (PLA), corn starch and Solanyl in order of decreasing profits. Taking into account uncertainties, flash co-pyrolysis is expected to be cheaper than composting biopolymer waste streams, except for corn starch. If uncertainty increases, composting also becomes more interesting than flash co-pyrolysis for waste of Solanyl. If the investment expenditure is 15% higher in practice than estimated, the preference for flash co-pyrolysis compared to composting biopolymer waste becomes less clear. Only when the system of green current certificates is dismissed, composting clearly is a much cheaper processing technique for disposing of biopolymer waste. Copyright © 2010 Elsevier Ltd. All rights reserved.

FURTHER EVALUATIONS OF RADIONUCLIDE PHYTOEXTRACTION FEASIBILITY USING SOILS FROM THE U.S. DEPARTMENT OF ENERGY COMPLEX

Energy Technology Data Exchange (ETDEWEB)

Jay Cornish

1999-01-01

Fiscal Year 98 (FY98) radionuclide phytoextraction studies involved resumption of the radiocesium-137 ({sup 137}Cs) investigations at Brookhaven National Laboratory (BNL) and the total uranium (U{sub t}) investigations at the Fernald Environmental Management Project (FEMP) site. This project was a collaborative effort involving scientists and engineers from MSE Technology Applications, Inc.; the US Department of Agriculture (USDA) Plant Growth Laboratory at Cornell University; Phytotech, Inc.; BNL; and FEMP. In both cases, the essential goal was to improve bioavailability, uptake, and transport of these contaminants from soil to leaf-and-stalk biomass (LSB). In particular, the practical goal was to demonstrate that about half the radionuclide contaminant mass present in near surface [{le}30 centimeters (cm) below ground surface (bgs)] soils could be transferred into LSB in approximately 5 years. Based on previous (1996) study results, it would require concentration ratios (CRs) of at 5-to-10 to achieve this goal. In addition, the rate of {sup 137}Cs removal must be {ge} 2.3% per year{sup -1} [i.e., (0.693/30.2) {center_dot} 100] to equal or exceed the loss of this radionuclide through natural decay. This report first presents and discusses the results from greenhouse and field evaluations of {sup 137}Cs uptake from rooting zone soils (0-15 cm bgs) located near the Medical/Biological Research Building (No. 490) at BNL. Contamination of this site resulted from the use of near surface soils originating at the former Hazardous Waste Management Facility (HWMF), which served as a source of landscaping materials for erosion control, etc. Project personnel from USDA evaluated various combinations of nonradioactive solutions of cesium chloride (CsCl) and rubidium chloride, ammonium nitrate solution (NH{sub 4}NO{sub 3}), and humic acid suspensions to enhance and sustain {sup 137}Cs levels in soil solution. Of the plants grown in such amended soils, the highest CRs occurred

REVIEW OF ALTERNATIVE ENHANCED CHEMICAL CLEANING OPTIONS FOR SRS WASTE TANKS

Energy Technology Data Exchange (ETDEWEB)

Hay, M.; Koopman, D.

2009-08-01

A literature review was conducted to support the Task Technical and Quality Assurance Plan for Alternative Enhanced Chemical Cleaning (AECC) for sludge heel removal funded as part of the EM-21 Engineering and Technology program. The goal was to identify potential technologies or enhancements to the baseline oxalic acid cleaning process for chemically dissolving or mobilizing Savannah River Site (SRS) sludge heels. The issues with the potentially large volume of oxalate solids generated from the baseline process have driven an effort to find an improved or enhanced chemical cleaning technology for the tank heels. This literature review builds on a previous review conducted in 2003. A team was charged with evaluating the information in these reviews and developing recommendations of alternative technologies to pursue. The new information in this report supports the conclusion of the previous review that oxalic acid remains the chemical cleaning agent of choice for dissolving the metal oxides and hydroxides found in sludge heels in carbon steel tanks. The potential negative impact of large volumes of sodium oxalate on downstream processes indicates that the amount of oxalic acid used for chemical cleaning needs to be minimized as much as possible or the oxalic acid must be destroyed prior to pH adjustment in the receipt tank. The most straightforward way of minimizing the volume of oxalic acid needed for chemical cleaning is through more effective mechanical cleaning. Using a mineral acid to adjust the pH of the sludge prior to adding oxalic acid may also help to minimize the volume of oxalic acid used in chemical cleaning. If minimization of oxalic acid proves insufficient in reducing the volume of oxalate salts, several methods were found that could be used for oxalic acid destruction. For some waste tank heels, another acid or even caustic treatment (or pretreatment) might be more appropriate than the baseline oxalic acid cleaning process. Caustic treatment of high

Development of autochthonous microbial consortia for enhanced phytoremediation of salt-marsh sediments contaminated with cadmium

International Nuclear Information System (INIS)

Teixeira, Catarina; Almeida, C. Marisa R.; Nunes da Silva, Marta; Bordalo, Adriano A.; Mucha, Ana P.

2014-01-01

Microbial assisted phytoremediation is a promising, though yet poorly explored, new remediation technique. The aim of this study was to develop autochthonous microbial consortia resistant to cadmium that could enhance phytoremediation of salt-marsh sediments contaminated with this metal. The microbial consortia were selectively enriched from rhizosediments colonized by Juncus maritimus and Phragmites australis. The obtained consortia presented similar microbial abundance but a fairly different community structure, showing that the microbial community was a function of the sediment from which the consortia were enriched. The effect of the bioaugmentation with the developed consortia on cadmium uptake, and the microbial community structure associated to the different sediments were assessed using a microcosm experiment. Our results showed that the addition of the cadmium resistant microbial consortia increased J. maritimus metal phytostabilization capacity. On the other hand, in P. australis, microbial consortia amendment promoted metal phytoextraction. The addition of the consortia did not alter the bacterial structure present in the sediments at the end of the experiments. This study provides new evidences that the development of autochthonous microbial consortia for enhanced phytoremediation of salt-marsh sediments contaminated with cadmium might be a simple, efficient, and environmental friendly remediation procedure. Capsule abstract: Development of autochthonous microbial consortia resistant to cadmium that enhanced phytoremediation by salt-marsh plants, without a long term effect on sediment bacterial diversity. - Highlights: • Cd resistant microbial consortia were developed and applied to salt-marsh sediments. • In Phragmites australis the consortia amendment promoted metal phytoextraction. • The consortia addition increased Juncus maritimus phytostabilization capacity. • No long term changes on the rhizosediment bacterial structure were observed

Development of autochthonous microbial consortia for enhanced phytoremediation of salt-marsh sediments contaminated with cadmium

Energy Technology Data Exchange (ETDEWEB)

Teixeira, Catarina [Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Universidade do Porto, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Laboratório de Hidrobiologia e Ecologia, Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto (Portugal); Almeida, C. Marisa R.; Nunes da Silva, Marta [Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Universidade do Porto, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Bordalo, Adriano A. [Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Universidade do Porto, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Laboratório de Hidrobiologia e Ecologia, Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto (Portugal); Mucha, Ana P., E-mail: amucha@ciimar.up.pt [Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Universidade do Porto, Rua dos Bragas, 289, 4050-123 Porto (Portugal)

2014-09-15

Microbial assisted phytoremediation is a promising, though yet poorly explored, new remediation technique. The aim of this study was to develop autochthonous microbial consortia resistant to cadmium that could enhance phytoremediation of salt-marsh sediments contaminated with this metal. The microbial consortia were selectively enriched from rhizosediments colonized by Juncus maritimus and Phragmites australis. The obtained consortia presented similar microbial abundance but a fairly different community structure, showing that the microbial community was a function of the sediment from which the consortia were enriched. The effect of the bioaugmentation with the developed consortia on cadmium uptake, and the microbial community structure associated to the different sediments were assessed using a microcosm experiment. Our results showed that the addition of the cadmium resistant microbial consortia increased J. maritimus metal phytostabilization capacity. On the other hand, in P. australis, microbial consortia amendment promoted metal phytoextraction. The addition of the consortia did not alter the bacterial structure present in the sediments at the end of the experiments. This study provides new evidences that the development of autochthonous microbial consortia for enhanced phytoremediation of salt-marsh sediments contaminated with cadmium might be a simple, efficient, and environmental friendly remediation procedure. Capsule abstract: Development of autochthonous microbial consortia resistant to cadmium that enhanced phytoremediation by salt-marsh plants, without a long term effect on sediment bacterial diversity. - Highlights: • Cd resistant microbial consortia were developed and applied to salt-marsh sediments. • In Phragmites australis the consortia amendment promoted metal phytoextraction. • The consortia addition increased Juncus maritimus phytostabilization capacity. • No long term changes on the rhizosediment bacterial structure were observed.

Phytoextraction and accumulation of mercury in three plant species: Indian mustard (Brassica juncea), beard grass (Polypogon monospeliensis), and Chinese brake fern (Pteris vittata).

Science.gov (United States)

Su, Yi; Han, Fengxiang X; Chen, Jian; Sridhar, B B Maruthi; Monts, David L

2008-01-01

The objective of this research was to screen and search for suitable plant species to phytoextract mercury-contaminated soil. Our effort focused on using some of the known metal-accumulating wild-type plants since no natural plant species with mercury-hyperaccumulat ing properties has yet been identified. Three plant species were evaluated for their uptake efficiency for mercury: Indian mustard (Brassica juncea), beard grass (Polypogon monospeliensis), and Chinese brake fern (Pteris vittata). Four sets of experiments were conducted to evaluate the phytoremediation potential of these three plant species: a pot study with potting mix where mercury was provided daily as HgCl2 solution; experiments with freshly mercury-spiked soil; and a study with aged soils contaminated with different mercury sources (HgCl2, Hg(NO3)2, and HgS). Homemade sunlit chambers were also used to study foliar uptake of Hg from ambient air. Among the three plant species, Chinese brake fern showed the least stress symptoms resulting from mercury exposure and had the highest mercury accumulation. Our results indicate that Chinese brake fern may be a potential candidate for mercury phytoextraction. We found that mercury contamination is biologically available for plant uptake and accumulation, even if the original and predominating mercury form is HgS, and also after multiple phytoremediation cycles.

DOE's Phytoremediation Program

International Nuclear Information System (INIS)

Levine, R.S.

1996-01-01

This presentation contains an outline of the US DOE's phytoremediation program. A brief overview of the goals, infrastructure, and results of the program is presented. Environmental contaminants addressed include chlorinated hydrocarbons, metals, radionuclides, inorganic wastes, and mixed hazardous and radioactive wastes. Studies of soil remediation using phytoextraction and water remediation using rhizofiltration are briefly described

Utilizing waste materials to enhance mechanical and durability characteristics of concrete incorporated with silica fume

Directory of Open Access Journals (Sweden)

Hamza Ali

2017-01-01

Full Text Available Construction and demolition wastes are increasing significantly due to augmented boom of modern construction. Although the partial cement replacement materials do promote the idea of sustainable construction, the use of construction and demolition waste can also be considered to be viable option to advance the sustainability in modern construction practices. This paper investigates the use of industrial waste materials namely marble dust and crushed bricks as replacement of natural fine aggregates along with the use of silica fume as a partial cement replacement on the mechanical properties and durability characteristics of concrete. Partial replacement levels of waste materials were 10 and 20 percent by volume while the partial replacement level of silica fume was kept to 20 percent at all concrete samples. The results reported in this paper show that the use of marble dust as a replacement material to the natural fine aggregates resulted in an increase in the mechanical properties of concrete. However, the use of crushed bricks did not substantially contribute in the development of strength. Water permeability of concrete incorporated with both silica fume and waste materials (marble dust and crushed bricks decreased significantly. The decrease in water permeability of concrete was attributed to the pozzolanic reaction of silica fume with calcium hydroxide of cement and the filler effect of the waste materials of marble dust and crushed bricks. The use of waste materials also enhance the freeze and thaw resistance of concrete. Authors strongly suggest that the pozzolanic reaction and the development of the microstructure of the concrete through the use of waste materials are largely responsible from the advances in the durability of concrete.

Model evaluation of plant metal content and biomass yield for the phytoextraction of heavy metals by switchgrass.

Science.gov (United States)

Chen, Bo-Ching; Lai, Hung-Yu; Juang, Kai-Wei

2012-06-01

To better understand the ability of switchgrass (Panicum virgatum L.), a perennial grass often relegated to marginal agricultural areas with minimal inputs, to remove cadmium, chromium, and zinc by phytoextraction from contaminated sites, the relationship between plant metal content and biomass yield is expressed in different models to predict the amount of metals switchgrass can extract. These models are reliable in assessing the use of switchgrass for phytoremediation of heavy-metal-contaminated sites. In the present study, linear and exponential decay models are more suitable for presenting the relationship between plant cadmium and dry weight. The maximum extractions of cadmium using switchgrass, as predicted by the linear and exponential decay models, approached 40 and 34 μg pot(-1), respectively. The log normal model was superior in predicting the relationship between plant chromium and dry weight. The predicted maximum extraction of chromium by switchgrass was about 56 μg pot(-1). In addition, the exponential decay and log normal models were better than the linear model in predicting the relationship between plant zinc and dry weight. The maximum extractions of zinc by switchgrass, as predicted by the exponential decay and log normal models, were about 358 and 254 μg pot(-1), respectively. To meet the maximum removal of Cd, Cr, and Zn, one can adopt the optimal timing of harvest as plant Cd, Cr, and Zn approach 450 and 526 mg kg(-1), 266 mg kg(-1), and 3022 and 5000 mg kg(-1), respectively. Due to the well-known agronomic characteristics of cultivation and the high biomass production of switchgrass, it is practicable to use switchgrass for the phytoextraction of heavy metals in situ. Copyright © 2012 Elsevier Inc. All rights reserved.

Phytoextraction and phytoexcretion of Cd by the leaves of Tamarix smyrnensis growing on contaminated non-saline and saline soils

International Nuclear Information System (INIS)

Manousaki, Eleni; Kadukova, Jana; Papadantonakis, Nikolaos; Kalogerakis, Nicolas

2008-01-01

Phytoremediation and more specifically phytoextraction, is an alternative restoration strategy for the clean up of heavy metal contaminated soils. Phytoextraction can only be successful if suitable plant species colonize the contaminated area, extract the toxic substances and accumulate them in their above ground tissues. In this study, the salt cedar Tamarix smyrnensis that is a widespread salt-tolerant plant in the Mediterranean region has been investigated. A pot experiment is conducted with T. smyrnensis grown in polluted soil with 16 ppm of cadmium and at three different salt concentrations (0.0, 0.5, 3.0% NaCl) for a 10-week period. It took place in an open-air area with natural light, at ambient temperature and humidity in an effort to keep the plants under conditions as similar as possible to those in the field. However, care was taken not to let them be rained on. Temperature ranged from 19 to 50 deg. C with 33 and 21 deg. C being the average day and night temperature, respectively. Humidity ranged from 28% to 87% with a 13-14 h photoperiod. The specific aims of this work are to investigate the accumulation of cadmium via root uptake at different saline conditions and cadmium excretion through salt glands on the surface of the leaves as a probable detoxification mechanism of the plant. Furthermore, measurements of chlorophyll content, biomass, and shoot length are used to evaluate the potential of the plant for the removal of cadmium from contaminated saline and non-saline soils. The experimental data suggest that increased soil salinity results in an increase of the cadmium uptake by T. smyrnensis. Analysis of white salt crystals taken from glandular tissue confirmed the fact that this plant excretes cadmium through its salt glands on the surface of the leaves as a possible detoxification mechanism in order to resist metal toxicity. Excreted cadmium is again released into the environment and it is redeposited on the top soil. Furthermore, increased

Anaerobic co-digestion of the organic fraction of municipal solid waste with FOG waste from a sewage treatment plant: Recovering a wasted methane potential and enhancing the biogas yield

International Nuclear Information System (INIS)

Martin-Gonzalez, L.; Colturato, L.F.; Font, X.; Vicent, T.

2010-01-01

Anaerobic digestion is applied widely to treat the source collected organic fraction of municipal solid wastes (SC-OFMSW). Lipid-rich wastes are a valuable substrate for anaerobic digestion due to their high theoretical methane potential. Nevertheless, although fat, oil and grease waste from sewage treatment plants (STP-FOGW) are commonly disposed of in landfill, European legislation is aimed at encouraging more effective forms of treatment. Co-digestion of the above wastes may enhance valorisation of STP-FOGW and lead to a higher biogas yield throughout the anaerobic digestion process. In the present study, STP-FOGW was evaluated as a co-substrate in wet anaerobic digestion of SC-OFMSW under mesophilic conditions (37 o C). Batch experiments carried out at different co-digestion ratios showed an improvement in methane production related to STP-FOGW addition. A 1:7 (VS/VS) STP-FOGW:SC-OFMSW feed ratio was selected for use in performing further lab-scale studies in a 5 L continuous reactor. Biogas yield increased from 0.38 ± 0.02 L g VS feed -1 to 0.55 ± 0.05 L g VS feed -1 as a result of adding STP-FOGW to reactor feed. Both VS reduction values and biogas methane content were maintained and inhibition produced by long chain fatty acid (LCFA) accumulation was not observed. Recovery of a currently wasted methane potential from STP-FOGW was achieved in a co-digestion process with SC-OFMSW.

Effective dialogue: Enhanced public engagement as a legitimising tool for municipal waste management decision-making

International Nuclear Information System (INIS)

Garnett, Kenisha; Cooper, Tim

2014-01-01

Highlights: • A review of public engagement in waste management decision-making is undertaken. • Enhanced public engagement is explored as a means to legitimise waste decisions. • Analytical–deliberative processes are explored as a tool for effective dialogue. • Considerations for integrating public values with technical analysis are outlined. • Insights into the design of appropriate public engagement processes are provided. - Abstract: The complexity of municipal waste management decision-making has increased in recent years, accompanied by growing scrutiny from stakeholders, including local communities. This complexity reflects a socio-technical framing of the risks and social impacts associated with selecting technologies and sites for waste treatment and disposal facilities. Consequently there is growing pressure on local authorities for stakeholders (including communities) to be given an early opportunity to shape local waste policy in order to encourage swift planning, development and acceptance of the technologies needed to meet statutory targets to divert waste from landfill. This paper presents findings from a research project that explored the use of analytical–deliberative processes as a legitimising tool for waste management decision-making. Adopting a mixed methods approach, the study revealed that communicating the practical benefits of more inclusive forms of engagement is proving difficult even though planning and policy delays are hindering development and implementation of waste management infrastructure. Adopting analytical–deliberative processes at a more strategic level will require local authorities and practitioners to demonstrate how expert-citizen deliberations may foster progress in resolving controversial issues, through change in individuals, communities and institutions. The findings suggest that a significant shift in culture will be necessary for local authorities to realise the potential of more inclusive decision

Effective dialogue: Enhanced public engagement as a legitimising tool for municipal waste management decision-making

Energy Technology Data Exchange (ETDEWEB)

Garnett, Kenisha, E-mail: k.garnett@cranfield.ac.uk [Institute for Environment, Health, Risks and Futures, School of Environment, Energy and Agri-food, Cranfield University, Cranfield MK43 0AL (United Kingdom); Cooper, Tim, E-mail: t.h.cooper@ntu.ac.uk [School of Architecture Design and the Built Environment, Nottingham Trent University, Burton Street, Nottingham NG1 4BU (United Kingdom)

2014-12-15

Highlights: • A review of public engagement in waste management decision-making is undertaken. • Enhanced public engagement is explored as a means to legitimise waste decisions. • Analytical–deliberative processes are explored as a tool for effective dialogue. • Considerations for integrating public values with technical analysis are outlined. • Insights into the design of appropriate public engagement processes are provided. - Abstract: The complexity of municipal waste management decision-making has increased in recent years, accompanied by growing scrutiny from stakeholders, including local communities. This complexity reflects a socio-technical framing of the risks and social impacts associated with selecting technologies and sites for waste treatment and disposal facilities. Consequently there is growing pressure on local authorities for stakeholders (including communities) to be given an early opportunity to shape local waste policy in order to encourage swift planning, development and acceptance of the technologies needed to meet statutory targets to divert waste from landfill. This paper presents findings from a research project that explored the use of analytical–deliberative processes as a legitimising tool for waste management decision-making. Adopting a mixed methods approach, the study revealed that communicating the practical benefits of more inclusive forms of engagement is proving difficult even though planning and policy delays are hindering development and implementation of waste management infrastructure. Adopting analytical–deliberative processes at a more strategic level will require local authorities and practitioners to demonstrate how expert-citizen deliberations may foster progress in resolving controversial issues, through change in individuals, communities and institutions. The findings suggest that a significant shift in culture will be necessary for local authorities to realise the potential of more inclusive decision

Performance Enhancements to the Hanford Waste Treatment and Immobilization Plant Low-Activity Waste Vitrification System

International Nuclear Information System (INIS)

Hamel, W. F.; Gerdes, K.; Holton, L. K.; Pegg, I.L.; Bowan, B.W.

2006-01-01

The U.S Department of Energy Office of River Protection (DOE-ORP) is constructing a Waste Treatment and Immobilization Plant (WTP) for the treatment and vitrification of underground tank wastes stored at the Hanford Site in Washington State. The WTP comprises four major facilities: a pretreatment facility to separate the tank waste into high level waste (HLW) and low-activity waste (LAW) process streams, a HLW vitrification facility to immobilize the HLW fraction; a LAW vitrification facility to immobilize the LAW fraction, and an analytical laboratory to support the operations of all four treatment facilities. DOE has established strategic objectives to optimize the performance of the WTP facilities and the LAW and HLW waste forms to reduce the overall schedule and cost for treatment and vitrification of the Hanford tank wastes. This strategy has been implemented by establishing performance expectations in the WTP contract for the facilities and waste forms. In addition, DOE, as owner-operator of the WTP facilities, continues to evaluate 1) the design, to determine the potential for performance above the requirements specified in the WTP contract; and 2) improvements in production of the LAW and HLW waste forms. This paper reports recent progress directed at improving production of the LAW waste form. DOE's initial assessment, which is based on the work reported in this paper, is that the treatment rate of the WTP LAW vitrification facility can be increased by a factor of 2 to 4 with a combination of revised glass formulations, modest increases in melter glass operating temperatures, and a second-generation LAW melter with a larger surface area. Implementing these improvements in the LAW waste immobilization capability can benefit the LAW treatment mission by reducing the cost of waste treatment. (authors)

Uptake of heavy metals and As by Brassica juncea grown in a contaminated soil in Aznalcollar (Spain): The effect of soil amendments

International Nuclear Information System (INIS)

Clemente, Rafael; Walker, David J.; Bernal, M. Pilar

2005-01-01

Two crops of Brassica juncea (L.) Czern. were grown in a field experiment, at the site affected by the toxic spillage of acidic, metal-rich waste in Aznalcollar (Seville, Spain), to study its metal accumulation and the feasibility of its use for metal phytoextraction. The effects of organic soil amendments (cow manure and mature compost) and lime on biomass production and plant survival were also assessed; plots without organic amendment and without lime were used as controls. Plots, with or without organic amendment, having pH -1 , respectively). The total uptake of heavy metals in the plants was relatively low, emphasising the problems faced when attempting to employ phytoextraction for clean-up of pluri-contaminated sites. - Although organic amendments improved soil conditions and plant growth, the phytoextraction capacity of Brassica juncea (cv. Z1) is too low for efficient soil remediation

Aged refuse enhances anaerobic digestion of waste activated sludge.

Science.gov (United States)

Zhao, Jianwei; Gui, Lin; Wang, Qilin; Liu, Yiwen; Wang, Dongbo; Ni, Bing-Jie; Li, Xiaoming; Xu, Rui; Zeng, Guangming; Yang, Qi

2017-10-15

In this work, a low-cost alternative approach (i.e., adding aged refuse (AR) into waste activated sludge) to significantly enhance anaerobic digestion of sludge was reported. Experimental results showed that with the addition dosage of AR increasing from 0 to 400 mg/g dry sludge soluble chemical oxygen demand (COD) increased from 1150 to 5240 mg/L at the digestion time of 5 d, while the maximal production of volatile fatty acids (VFA) increased from 82.6 to 183.9 mg COD/g volatile suspended solids. Although further increase of AR addition decreased the concentrations of both soluble COD and VFA, their contents in these systems with AR addition at any concentration investigated were still higher than those in the blank, which resulted in higher methane yields in these systems. Mechanism studies revealed that pertinent addition of AR promoted solubilization, hydrolysis, and acidogenesis processes and did not affect methanogenesis significantly. It was found that varieties of enzymes and anaerobes in AR were primary reason for the enhancement of anaerobic digestion. Humic substances in AR benefited hydrolysis and acidogenesis but inhibited methanogenesis. The effect of heavy metals in AR on sludge anaerobic digestion was dosage dependent. Sludge anaerobic digestion was enhanced by appropriate amounts of heavy metals but inhibited by excessive amounts of heavy metals. The relative abundances of microorganisms responsible for sludge hydrolysis and acidogenesis were also observed to be improved in the system with AR addition, which was consistent with the performance of anaerobic digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of arbuscular mycorrhizal fungi on the potential of three wild plant species for phytoextraction of mercury from small-scale gold mine tailings

Directory of Open Access Journals (Sweden)

A. Fiqri

2016-04-01

Full Text Available A study that was aimed to explore the effects of arbuscular mycorrhizal (AM fungi inoculation on the potential of wild plant species (Paspalum conjugatum, Cyperus kyllingia, and Lindernia crustacea for phytoextraction of mercury from small-scale gold mine tailings was conducted in a glasshouse. Each of the plant seedlings was planted in a plastic pot containing 10 kg of planting medium (mixture of tailings and compost; 50%: 50% by weight. Treatments tested were three plant species and doses of AM fungi inoculation, i.e. 0 and 30 spores/plant. At harvest of 63 days, plant shoot and root were analyzed for mercury concentration. The remaining planting media in the pots were used for growing maize for 84 days. The results showed that the most potential plant species for phytoextraction of mercury was Paspalum conjugatum, while the most mercury tolerant plant was Cyperus kyllingia. Without AM fungi inoculation, the highest accumulation of mercury (44.87 mg/kg was found in the root of Paspalum conjugatum. If AM fungi were inoculated, the highest accumulation of mercury (56.30 mg/kg was also found in the shoot of Paspalum conjugatum. Results of the second experiment proved that the growth and biomass production of maize after mycophytoextraction by the plant species were higher than those of maize grown on media without mycophytoextraction of mercury.

Enhanced phytoremediation of arsenic contaminated land.

Science.gov (United States)

Jankong, P; Visoottiviseth, P; Khokiattiwong, S

2007-08-01

In an attempt to clean up arsenic (As) contaminated soil, the effects of phosphorus (P) fertilizer and rhizosphere microbes on arsenic accumulation by the silverback fern, Pityrogramma calomelanos, were investigated in both greenhouse and field experiments. Field experiments were conducted in Ron Phibun District, an As-contaminated area in Thailand. Soil (136-269 microg As g(-1)) was collected there and used in the greenhouse experiment. Rhizosphere microbes (bacteria and fungi) were isolated from roots of P. calomelanos growing in Ron Phibun District. The results showed that P-fertilizer significantly increased plant biomass and As accumulation of the experimental P. calomelanos. Rhizobacteria increased significantly the biomass and As content of the test plants. Thus, P-fertilizer and rhizosphere bacteria enhanced As-phytoextraction. In contrast, rhizofungi reduced significantly As concentration in plants but increased plant biomass. Therefore, rhizosphere fungi exerted their effects on phytostabilization.

Correlates of domestic waste management and related health outcomes in Sunyani, Ghana: a protocol towards enhancing policy.

Science.gov (United States)

Addo, Henry O; Dun-Dery, Elvis J; Afoakwa, Eugenia; Elizabeth, Addai; Ellen, Amposah; Rebecca, Mwinfaug

2017-07-03

.99), were all significant predictors of waste management practice. Cholera which is a hygiene related disease was three times more likely to determine households' waste management practice (AOR 3.22; Cl 1.33, 7.84). Considering the low waste management practice among households, there is the need for improved policy and enhanced education on proper waste management practice among households.

Soil availability, plant uptake and soil to plant transfer of 99Tc-- A review

International Nuclear Information System (INIS)

Bennett, Roy; Willey, Neil

2003-01-01

The fission yield of 99 Tc from 239 Pu and 235 U is similar to that of 137 Cs or 90 Sr and it is therefore an important component of nuclear weapons fall-out, nuclear waste and releases from nuclear facilities. There is particular current interest in 99 Tc transfer from soil to plants for: (a) environmental impact assessments for terrestrial nuclear waste repositories, and (b) assessments of the potential for phytoextraction of radionuclides from contaminated effluent and soil. Vascular plants have high 99 Tc uptake capacity, a strong tendency to transport it to shoot material and accumulate it in vegetative rather than reproductive structures. The mechanisms that control 99 Tc entry to plants have not been identified and there has been little discussion of the potential for phytoextraction of 99 Tc contaminated effluents or soil. Here we review soil availability, plant uptake mechanisms and soil to plant transfer of 99 Tc in the light of recent advances in soil science, plant molecular biology and phytoextraction technologies. We conclude that 99 Tc might not be highly available in the long term from up to 50% of soils worldwide, and that no single mechanism that might be easily targeted by recombinant DNA technologies controls 99 Tc uptake by plants. Overall, we suggest that Tc might be less available in terrestrial ecosystems than is often assumed but that nevertheless the potential of phytoextraction as a decontamination strategy is probably greater for 99 Tc than for any other nuclide of radioecological interest

enhancing pineaple waste utilization as animalfeed through nutrient

African Journals Online (AJOL)

Rose

2013-10-23

Oct 23, 2013 ... that fermentation of pineapple waste by solid state fermentation using the fungi A. niger and T. viride significantly (P < 0.05) ... The conventional commercial feeds ... waste management, biomass energy conservation and.

SECONDARY WASTE MANAGEMENT STRATEGY FOR EARLY LOW ACTIVITY WASTE TREATMENT

Energy Technology Data Exchange (ETDEWEB)

TW, CRAWFORD

2008-07-17

This study evaluates parameters relevant to River Protection Project secondary waste streams generated during Early Low Activity Waste operations and recommends a strategy for secondary waste management that considers groundwater impact, cost, and programmatic risk. The recommended strategy for managing River Protection Project secondary waste is focused on improvements in the Effiuent Treatment Facility. Baseline plans to build a Solidification Treatment Unit adjacent to Effluent Treatment Facility should be enhanced to improve solid waste performance and mitigate corrosion of tanks and piping supporting the Effiuent Treatment Facility evaporator. This approach provides a life-cycle benefit to solid waste performance and reduction of groundwater contaminants.

Enhanced accumulation of copper and lead in amaranth (Amaranthus paniculatus), Indian mustard (Brassica juncea) and sunflower (Helianthus annuus).

Science.gov (United States)

Rahman, Motior M; Azirun, Sofian M; Boyce, Amru N

2013-01-01

Soil contamination by copper (Cu) and lead (Pb) is a widespread environmental problem. For phytoextraction to be successful and viable in environmental remediation, strategies that can improve plant uptake must be identified. In the present study we investigated the use of nitrogen (N) fertilizer as an efficient way to enhance accumulation of Cu and Pb from contaminated industrial soils into amaranth, Indian mustard and sunflower. Plants were grown in a greenhouse and fertilized with N fertilizer at rates of 0, 190 and 380 mg kg⁻¹ soil. Shoots, roots and total accumulation of Cu and Pb, transfer factor (TF), translocation index were assessed to evaluate the transport and translocation ability of tested plants. Addition of N fertilizer acidified the industrial soil and caused the pH to decrease to 5.5 from an initial pH of 6.9. Industrial soil amended with N fertilizer resulted in the highest accumulation of Pb and Cu (for Pb 10.1-15.5 mg kg⁻¹, for Cu 11.6-16.8 mg kg⁻¹) in the shoots, which was two to four folds higher relative to the concentration in roots in all the three plants used. Sunflower removed significantly higher Pb (50-54%) and Cu (34-38%) followed by amaranth and Indian mustard from industrial soils with the application of N fertilizer. The TF was Sunflower is the best plant species to carry out phytoextraction of Pb and Cu. In contrast, Pb and Cu removal by Indian mustard and amaranth shows great potential as quick and short duration vegetable crops. The results suggest that the application of N fertilizer in contaminated industrial soil is an effective amendment for the phytoextraction of Pb and Cu from contaminated industrial soils.

Phytoextraction for clean-up of low-level uranium contaminated soil evaluated

International Nuclear Information System (INIS)

Vandenhove, H.; Hees, M. van

2004-01-01

Spills in the nuclear fuel cycle have led to soil contamination with uranium. In case of small contamination just above release levels, low-cost yet sufficiently efficient remedial measures are recommended. This study was executed to test if low-level U contaminated sandy soil from a nuclear fuel processing site could be phytoextracted in order to attain the required release limits. Two soils were tested: a control soil (317 Bq 238 U kg -1 ) and the same soil washed with bicarbonate (69 Bq 238 U kg -1 ). Ryegrass (Lolium perenne cv. Melvina) and Indian mustard (Brassica juncea cv. Vitasso) were used as test plants. The annual removal of soil activity by the biomass was less than 0.1%. The addition of citric acid (25 mmol kg -1 ) 1 week before the harvest increased U uptake up to 500-fold. With a ryegrass and mustard yield of 15,000 and 10,000 kg ha -1 , respectively, up to 3.5% and 4.6% of the soil activity could be removed annually by the biomass. With a desired activity reduction level of 1.5 and 5 for the bicarbonate-washed and control soil, respectively, it would take 10-50 years to attain the release limit. However, citric acid addition resulted in a decreased dry weight production

Effect of Pseudomonas fluorescens and pyoverdine on the phytoextraction of cesium by red clover in soil pots and hydroponics.

Science.gov (United States)

Hazotte, Alice; Péron, Olivier; Gaudin, Pierre; Abdelouas, Abdesselam; Lebeau, Thierry

2018-05-12

With the aim of improving the phytoextraction rate of cesium (Cs), the effect of Pseudomonas fluorescens ATCC 17400 and its siderophore pyoverdine (PVD) on the uptake of Cs by red clover was studied in soil pots. This work also provides a mechanistic understanding of the Cs-bacteria (or PVD)-illite-plant interactions by using a simplified experimental design, i.e., hydroponics with either Cs in solution or Cs-spiked illite in suspension. For soil spiked with 11.2 mmol kg -1 (1480 mg kg -1 ) of Cs, 0.43% of total Cs was taken up by red clover in 12 days (119 μmol g -1 (16 mg g -1 ) of Cs dry matter in roots and 40 μmol g -1 (5 mg g -1 ) in shoots). In hydroponics with Cs in solution (0.1 mmol L -1 or 13 mg L -1 ), 75% of Cs was taken up vs. only 0.86% with Cs-spiked illite suspension. P. fluorescens and PVD did not increase Cs concentrations in aboveground parts and roots of red clover and even decreased them. The damaging effect of PVD on red clover growth was demonstrated with the biomass yielding 66% of the control in soil pots (and 100% mortality after 12 days of exposition) and only 56% in hydroponics (78% with illite in suspension). Nonetheless, PVD and, to a lesser extent, P. fluorescens increased the translocation factor up to a factor of 2.8. This study clearly showed a direct damaging effect of PVD and to a lower extent the retention of Cs by biofilm covering both the roots and illite, both resulting in the lower phytoextraction efficiency.

Enhanced high-solids anaerobic digestion of waste activated sludge by the addition of scrap iron.

Science.gov (United States)

Zhang, Yaobin; Feng, Yinghong; Yu, Qilin; Xu, Zibin; Quan, Xie

2014-05-01

Anaerobic digestion of waste activated sludge usually requires pretreatment procedure to improve the bioavailability of sludge, which involves considerable energy and high expenditures. This study proposes a cost-effective method for enhanced anaerobic digestion of sludge without a pretreatment by directly adding iron into the digester. The results showed that addition of Fe(0) powder could enhance 14.46% methane yield, and Fe scrap (clean scrap) could further enhance methane yield (improving rate 21.28%) because the scrap has better mass transfer efficiency with sludge and liquid than Fe(0) powder. The scrap of Fe with rust (rusty scrap) could induce microbial Fe(III) reduction, which resulted in achieving the highest methane yield (improving rate 29.51%), and the reduction rate of volatile suspended solids (VSS) was also highest (48.27%) among Fe powder, clean scrap and rusty scrap. PCR-DGGE proved that the addition of rusty scrap could enhance diversity of acetobacteria and enrich iron-reducing bacteria to enhance degradation of complex substrates. Copyright © 2014 Elsevier Ltd. All rights reserved.

Phytoextraction. A new pilot-plant project for the soil decontamination; Fitodecontaminazione. Un sistema pilota per la fito-decontaminazione di suoli inquinati da piombo

Energy Technology Data Exchange (ETDEWEB)

Bregante, M.; Paganetto, A.; Magistrelli, P.; Martella, L.; Gambale, F. [Consiglio Nazionale delle Ricerche, Istituto di Cibernetica e Biofisica, Genoa (Italy); Sacchi, G.A.; Rivetta, A.; Cocucci, R. [Milan Univ., Milan (Italy). Dipt. di Produzione Vegetale

2001-12-01

The environmental pollution is continuously increasing owing to anthropic activity. High concentrations of heavy metals may have drastic consequences on human health, particularly on children development. Conventional approaches have high economical and environmental costs that do not allow soil decontamination unless sites are particularly valuable. Phytoextraction uses plants producing biomass to transfer metals from the soil to the aerial parts of the plants at the expenses of solar energy. This work illustrates the activity performed within a Life-Environment european project in order to verify whether phytoremediation can be transferred from the laboratory scale to the field scale. [Italian] L'inquinamento del suolo dovuto all'accumulo di metalli come conseguenza delle attivita' umane sta continuamente e drammaticamente aumentando. Principali cause di contaminazione sono l'accumulo di rifiuti urbani, l'utilizzo di fertilizzanti, il traffico motorizzato, gli inceneritori, le centrali termoelettriche, le emissiioni industriali nocive, lo sfruttamento e dismissione di miniere. La decontaminazione di suoli inquinati da metalli e' un problema estremamente difficile da trattare. La bonifica di suoli inquinati da metalli mediante l'utilizzo di piante metallofite e/o agronomiche (fitoestrazione) emerge quindi come una tecnica estremamente interessante. Viene percio' illustrato il progetto PhyLeS (Phytoextraction of Lead from Soil), un progetto pilota finanziato dal programma Europeo Life/Ambiente (DG XI), che si propone di verficare i potenziali vantaggi e la trasferibilita' della metodica di fitoestrazione assistita dalla scala di laboratorio a quella di campo.

Enhanced sludge washing evaluation plan

Energy Technology Data Exchange (ETDEWEB)

Jensen, R.D.

1994-09-01

The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices.

Enhanced sludge washing evaluation plan

International Nuclear Information System (INIS)

Jensen, R.D.

1994-09-01

The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices

Using solar heat to enhance waste-heat use; Solarthermische Abwaermenutzung; Aufwertung von Abwaerme mittels Solarthermie zur Erzeugung hochwertiger Prozessenergie - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Mueller, R. [BMG Engineering AG, Schlieren (Switzerland); Luzzi, A.; Marty, H. [HSR, Hochschule fuer Technik, SPF Institut fuer Solartechnik, Rapperswil (Switzerland)

2008-12-15

This final report for Swiss Federal Office of Energy (SFOE) presents the work done in a project involving the use of solar heat to enhance the use of waste heat at a chemical plant in Nyon, Switzerland. On the basis of a study carried out in 2006/2007, which looked at the reduction of process energy demand of a production site where an agent is produced in batch operation, possibilities for the recovery of waste heat were identified. The relatively low temperatures of the existing waste heat flows have, however, complicated its efficient use. This reflects a problem with waste heat use in industrial processes that can often be observed. Due to the sunny location in Nyon, a concept using solar energy to increase the temperature level of this waste heat has been developed. The objective of this analysis was the technical and economical assessment of such an installation and its transferability to other sites. Variants are presented and their economic viability is discussed.

Phytoextraction and fractionation of heavy metals in soil after multiple applications of natural chelants Fitoextração e fracionamento de metais pesados em solo após múltiplas aplicações de ácidos orgânicos

Directory of Open Access Journals (Sweden)

Évio Eduardo Chaves de Melo

2008-02-01

Full Text Available Chelate-assisted phytoextraction of heavy metals is a promising approach to clean up polluted soils. However, the most successful chelants tested so far are synthetic agents that barely degrade in soil, increasing the metal leaching risks. Natural organic acids have been proposed to enhance phytoextraction due to their higher biodegradability, but they can also be a drawback for efficient phytoextraction. This work was carried out to compare the effectiveness of multiple applications of citric and gallic acids on the availability in soil and accumulation of Cd, Pb, Cu, and Zn by velvet bean (Stizolobium aterrimum plants. The organic acids were added as follows: 5 mmol kg-1 in the 28th cultivation day; two doses of 5 mmol kg-1 at the 28th and 31st day; and three applications at the same rate at the 28th, 31st, and 34th day of velvet bean cultivation. Soil samples were sequentially extracted and soil solution metal concentrations assessed. Neither citric acid nor gallic acid was efficient for metals phytoextraction. In general, low molecular weight organic acids (LMWOA application increased the metal concentrations in the water soluble and exchangeable fractions. Zinc and Cu were retained mostly in the organic matter fraction. Zn was remobilized from the organic matter fraction through LMWOA application into the water soluble and exchangeable fractions. LMWOA mobilized Pb and Cu from iron oxides, but such an increase in solubility was not high enough to affect phytoextraction.Fitoextração de metais induzida por quelantes é uma técnica promissora para despoluição de solos. Entretanto, os quelantes mais eficientes são sintéticos e apresentam baixa taxa de biodegradação, o que aumenta o risco de lixiviação de metais. Ácidos orgânicos têm sido propostos para auxiliar na fitoextração, mas a sua rápida degradação pode ser limitante para a eficiência desta técnica. O objetivo do trabalho foi comparar a eficiência de aplica

Variation in copper and zinc tolerance and accumulation in 12 willow clones: implications for phytoextraction*

Science.gov (United States)

Yang, Wei-dong; Wang, Yu-yan; Zhao, Feng-liang; Ding, Zhe-li; Zhang, Xin-cheng; Zhu, Zhi-qiang; Yang, Xiao-e

2014-01-01

Willows (Salix spp.) have shown high potential for the phytoextraction of heavy metals. This study compares variations in copper (Cu) and zinc (Zn) tolerance and accumulation potential among 12 willow clones grown in a nutrient solution treated with 50 μmol/L of Cu or Zn, respectively. The results showed differences in the tolerance and accumulation of Cu and Zn with respect to different species/clones. The biomass variation among clones in response to Cu or Zn exposure ranged from the stimulation of growth to inhibition, and all of the clones tested showed higher tolerance to Cu than to Zn. The clones exhibited less variation in Cu accumulation but larger variation in Zn accumulation. Based on translocation factors, it was found that most of the Cu was retained in the roots and that Zn was more mobile than Cu for all clones. It is concluded that most willow clones are good accumulators of Zn and Cu. PMID:25183033

Bioaugmentation-assisted phytoextraction of Co, Pb and Zn: an assessment with a phosphate-solubilizing bacterium isolated from metal-contaminated mines of Boryeong Area in South Korea

Directory of Open Access Journals (Sweden)

Arunakumara, KKIU.

2015-01-01

Full Text Available Description of the subject. Make use of microbes having remarkable metal tolerance and plant growth-promoting abilities to remediate metal-contaminated soils. Objectives. The objectives were to isolate phosphate solubilizing bacterial strain, assess metal (Co, Pb and Zn mobilization potential of the strain and to evaluate the effects of the strain on growth and uptake of metals by Helianthus annuus. Method. A phosphate solubilizing bacterium was isolated from metal-contaminated soils. Heavy metal (Co, Pb and Zn tolerance of the strain was assessed using the agar dilution method. Bacterial-assisted growth promotion and metal uptake by H. annuus was evaluated in a pot experiment. The impact of bacterial inoculation on the mobility of metals in soil was investigated in a batch experiment. Results. The strain showed close proximity with Klebsiella oxytoca JCM1665, according to 16S rRNA sequence analysis. The strain was efficient in solubilizing phosphate, both in the presence and absence of metals. Inoculation of the strain enhanced the growth of H. annuus (49, 22 and 39% respectively in Co, Pb and Zn contaminated soils compared to non-inoculated plants. Accumulation and translocation of Co, Pb and Zn from roots to shoots were also enhanced by the strain. Water soluble fraction of Co, Pb and Zn in soil was increased by 51, 24 and 76% respectively in inoculated soils with regard to those of non-inoculated soils. Conclusions. Taking the plant growth promotion and metal mobilizing potential of the strain into account, practical application of the strain in enhancing phytoextraction of Co, Pb and Zn from contaminated soils could be recommended.

Enhancement of cemented waste forms by supercritical CO2 carbonation of standard portland cements

International Nuclear Information System (INIS)

Rubin, J.B.; Carey, J.; Taylor, C.M.V.

1997-01-01

We are conducting experiments on an innovative transformation concept, using a traditional immobilization technique, that may significantly reduce the volume of hazardous or radioactive waste requiring transport and long-term storage. The standard practice for the stabilization of radioactive salts and residues is to mix them with cements, which may include additives to enhance immobilization. Many of these wastes do not qualify for underground disposition, however, because they do not meet disposal requirements for free liquids, decay heat, head-space gas analysis, and/or leachability. The treatment method alters the bulk properties of a cemented waste form by greatly accelerating the natural cement-aging reactions, producing a chemically stable form having reduced free liquids, as well as reduced porosity, permeability and pH. These structural and chemical changes should allow for greater actinide loading, as well as the reduced mobility of the anions, cations, and radionuclides in aboveground and underground repositories. Simultaneously, the treatment process removes a majority of the hydrogenous material from the cement. The treatment method allows for on-line process monitoring of leachates and can be transported into the field. We will describe the general features of supercritical fluids, as well as the application of these fluids to the treatment of solid and semi-solid waste forms. some of the issues concerning the economic feasibility of industrial scale-up will be addressed, with particular attention to the engineering requirements for the establishment of on-site processing facilities. Finally, the initial results of physical property measurements made on portland cements before and after supercritical fluid processing will be presented

Efficiency of repeated phytoextraction of cadmium and zinc from an agricultural soil contaminated with sewage sludge.

Science.gov (United States)

Luo, Kai; Ma, Tingting; Liu, Hongyan; Wu, Longhua; Ren, Jing; Nai, Fengjiao; Li, Rui; Chen, Like; Luo, Yongming; Christie, Peter

2015-01-01

Long-term application of sewage sludge resulted in soil cadmium (Cd) and zinc (Zn) contamination in a pot experiment conducted to phytoextract Cd/Zn repeatedly using Sedum plumbizincicola and Apium graceolens in monoculture or intercropping mode eight times. Shoot yields and soil physicochemical properties changed markedly with increasing number of remediation crops when the two plant species were intercropped compared with the unplanted control soil and the two monoculture treatments. Changes in soil microbial indices such as average well colour development, soil enzyme activity and soil microbial counts were also significantly affected by the growth of the remediation plants, especially intercropping with S. plumbizincicola and A. graveolens. The higher yields and amounts of Cd taken up indicated that intercropping of the hyperaccumulator and the vegetable species may be suitable for simultaneous agricultural production and soil remediation, with larger crop yields and higher phytoremediation efficiencies than under monoculture conditions.

Growth Conditions and Gamma-Irradiation as Enhancers of Cellulase Production by Bacillus subtilis Using Solid State Fermentation of Banana Wastes

International Nuclear Information System (INIS)

EI Shafey, H.M.

2008-01-01

In the present investigation trials have been carried out to study the effect of growth conditions and y-irradiation on the enhancement of cellulases using banana wastes. Bacterial strains were isolated from degraded banana wastes. Using the plate screening medium, a hypercelIulolytic isolate was selected on the basis of the diameter of the hydrolysis zone surrounding the colonies, and identified as Bacillus subtilis. Three method of pretreatment or the substrate were applied and compared in order to increase the susceptibility of the substrate to biodegradation. The methods used were autoclaving at 121 degree C for 60 min, acid hydrolysis using 2 N HCI, and alkali hydrolysis using 2 M NaOH. Pretreatment of the substrate (banana wastes) by autoclaving at 121 degree C for 60 minutes yielded the highest carboxymethyl cellulase (CMCase) and filter paper cellulase (FPase) enzyme activities in comparing with other methods. Production of CMCase and FPase was followed during changes of the growth conditions using solid state fermentation. Results showed that the two enzymes share the same growth factors for the maximum enzymatic production including 36 degree C incubation temperature, 72 hours incubation period, 60% moisture content, 20% v/w inoculum size, and initial ph 7.0. A gamma irradiation dose of 1.5 kGy was found to have an enhancing effect on the two enzymes production. Production of FPase enzyme was enhanced by 3.43 and 2.28% in pseudo stems and leaves, respectively. On the other hand, production of CMCase enzyme was slightly enhanced by 0.91 and 0.72% using pseudo stems and leaves respectively. Results also showed that banana leaves yielded higher CMCase and FPase enzymes than pseudo stems

Cadmium phytoextraction from loam soil in tropical southern China by Sorghum bicolor.

Science.gov (United States)

Wang, Xu; Chen, Can; Wang, Jianlong

2017-06-03

The cadmium (Cd) uptake characteristics by Sorghum bicolor cv. Nengsi 2# and Cowley from the acidic sandy loam soil (pH = 6.1) during the entire growth period (100 days) were investigated in pot outdoors in a tropical district of southern China, Hainan Island. The Cd-spiked levels in soil were set as 3 and 15 mg/kg. Correspondingly, the available Cd levels in soil extracted by Mehlich III solution were 2.71 and 9.41 mg/kg, respectively. Basically, two varieties in a full growth period (100 days) did not show a significant difference in their growth and Cd uptake. Under high Cd stress, the plant growth was inhibited and its biomass weight and height decreased by 38.7-51.5% and 27.6-28.5%, respectively. However, S. bicolor showed higher bioaccumulation capability of Cd from soil to plant [bioconcentration factor (BCF)>4], and higher transfer capability of Cd from roots to shoots [translocation factor (TF)>1] under high Cd stress; Cd contents in the roots, stems, and leaves of S. bicolor reached 43.79-46.07, 63.28-70.60, and 63.10-66.06 mg/kg, respectively. S. bicolor exhibited the potential phytoextraction capability for low or moderate Cd-contamination in acidic sandy loam soil.

Phytoextraction of heavy metals by willows growing in biosolids under field conditions.

Science.gov (United States)

Laidlaw, W S; Arndt, S K; Huynh, T T; Gregory, D; Baker, A J M

2012-01-01

Biosolids produced by sewage treatment facilities can exceed guideline thresholds for contaminant elements. Phytoextraction is one technique with the potential to reduce these elements allowing reuse of the biosolids as a soil amendment. In this field trial, cuttings of seven species/cultivars of Salix(willows) were planted directly into soil and into biosolids to identify their suitability for decontaminating biosolids. Trees were irrigated and harvested each year for three consecutive years. Harvested biomass was weighed and analyzed for the contaminant elements: As, Cd, Cu, Cr, Hg, Pb, Ni, and Zn. All Salix cultivars, except S. chilensis, growing in soils produced 10 to 20 t ha(-1) of biomass, whereas most Salix cultivars growing in biosolids produced significantly less biomass (metals from biosolids, driven by superior biomass increases and not high tissue concentrations. The willows were effectual in extracting the most soluble/exchangeable metals (Cd, 0.18; Ni, 0.40; and Zn, 11.66 kg ha(-1)), whereas Cr and Cu were extracted to a lesser degree (0.02 and 0.11 kg ha(-1)). Low bioavailable elements, As, Hg, and Pb, were not detectable in any of the aboveground biomass of the willows. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Enhanced HLW glass formulations for the waste treatment and immobilization plant

Energy Technology Data Exchange (ETDEWEB)

Kruger, Albert A. [DOE-WTP Project Office, US Department of Energy, Richland, Washington (United States)

2013-07-01

Current estimates and glass formulation efforts are conservative vis-a-vis achievable waste loadings. These formulations have been specified to ensure that glasses are homogenous, contain essentially no crystalline phases, are processable in joule-heated, ceramic-lined melters and meet WTP Contract terms. The WTP's overall mission will require the immobilization of tank waste compositions that are dominated by mixtures of aluminum, chromium, bismuth, iron, phosphorous, zirconium, and sulfur compounds as waste-limiting components. Glass compositions for these waste mixtures have been developed based upon previous experience and current glass property models. DOE has a testing program to develop and characterize HLW glasses with higher waste loadings. This work has demonstrated the feasibility of increases in waste loading from 25 wt% to 33-50 wt% (based on oxide loading) in the glass depending on the waste stream. It is expected these higher waste loading glasses will reduce the HLW canister production requirement by 25% or more. (authors)

Waste segregation procedures and benefits

International Nuclear Information System (INIS)

Fish, J.D.; Massey, C.D.; Ward, S.J.

1990-01-01

Segregation is a critical first step in handling hazardous and radioactive materials to minimize the generation of regulated wastes. In addition, segregation can significantly reduce the complexity and the total cost of managing waste. Procedures at Sandia National Laboratories, Albuquerque require that wastes be segregated, first, by waste type (acids, solvents, low level radioactive, mixed, classified, etc.). Higher level segregation requirements, currently under development, are aimed at enhancing the possibilities for recovery, recycle and reapplication; reducing waste volumes; reducing waste disposal costs, and facilitating packaging storage, shipping and disposal. 2 tabs

Integrated waste management - Looking beyond the solid waste horizon

International Nuclear Information System (INIS)

Seadon, J.K.

2006-01-01

Waste as a management issue has been evident for over four millennia. Disposal of waste to the biosphere has given way to thinking about, and trying to implement, an integrated waste management approach. In 1996 the United Nations Environmental Programme (UNEP) defined 'integrated waste management' as 'a framework of reference for designing and implementing new waste management systems and for analysing and optimising existing systems'. In this paper the concept of integrated waste management as defined by UNEP is considered, along with the parameters that constitute integrated waste management. The examples used are put into four categories: (1) integration within a single medium (solid, aqueous or atmospheric wastes) by considering alternative waste management options (2) multi-media integration (solid, aqueous, atmospheric and energy wastes) by considering waste management options that can be applied to more than one medium (3) tools (regulatory, economic, voluntary and informational) and (4) agents (governmental bodies (local and national), businesses and the community). This evaluation allows guidelines for enhancing success: (1) as experience increases, it is possible to deal with a greater complexity; and (2) integrated waste management requires a holistic approach, which encompasses a life cycle understanding of products and services. This in turn requires different specialisms to be involved in the instigation and analysis of an integrated waste management system. Taken together these advance the path to sustainability

The evaluation of growth and phytoextraction potential of Miscanthus x giganteus and Sida hermaphrodita on soil contaminated simultaneously with Cd, Cu, Ni, Pb, and Zn.

Science.gov (United States)

Kocoń, Anna; Jurga, Beata

2017-02-01

One of the cheapest, environmentally friendly methods for cleaning an environment polluted by heavy metals is phytoextraction. It builds on the uptake of pollutants from the soil by the plants, which are able to grow under conditions of high concentrations of toxic metals. The aim of this work was to assess the possibility of growing and phytoextraction potential of Miscanthus x giganteus and Sida hermaphrodita cultivated on two different soils contaminated with five heavy metals simultaneously: Cd, Cu, Ni, Pb, and Zn. A 3-year microplot experiment with two perennial energy crops, M. x giganteus and S. hermaphrodita, was conducted in the experimental station of IUNG-PIB in Poland (5° 25' N, 21° 58 'E), in the years of 2008-2010. Miscanthus was found more tolerant to concomitant soil contamination with heavy metals and produced almost double biomass than Sida in all three tested years, independent of soil type. Miscanthus collected greater amount of heavy metals (except for cadmium) in the biomass than Sida. Both energy crops absorb high levels of zinc, lower levels of lead, copper, and nickel, and absorbed cadmium at least, generally more metals were taken from the sandy soil, where plants also yielded better. Photosynthesis net rate of Miscanthus was on average 40% higher compared to Sida. Obtained results indicate that M. x giganteus and S. hermaphrodita can successfully be grown on moderately contaminated soil with heavy metals.

Revised cost savings estimate with uncertainty for enhanced sludge washing of underground storage tank waste

International Nuclear Information System (INIS)

DeMuth, S.

1998-01-01

Enhanced Sludge Washing (ESW) has been selected to reduce the amount of sludge-based underground storage tank (UST) high-level waste at the Hanford site. During the past several years, studies have been conducted to determine the cost savings derived from the implementation of ESW. The tank waste inventory and ESW performance continues to be revised as characterization and development efforts advance. This study provides a new cost savings estimate based upon the most recent inventory and ESW performance revisions, and includes an estimate of the associated cost uncertainty. Whereas the author's previous cost savings estimates for ESW were compared against no sludge washing, this study assumes the baseline to be simple water washing which more accurately reflects the retrieval activity along. The revised ESW cost savings estimate for all UST waste at Hanford is $6.1 B ± $1.3 B within 95% confidence. This is based upon capital and operating cost savings, but does not include development costs. The development costs are assumed negligible since they should be at least an order of magnitude less than the savings. The overall cost savings uncertainty was derived from process performance uncertainties and baseline remediation cost uncertainties, as determined by the author's engineering judgment

Unique Rhizosphere Micro-characteristics Facilitate Phytoextraction of Multiple Metals in Soil by the Hyperaccumulating Plant Sedum alfredii.

Science.gov (United States)

Hou, Dandi; Wang, Kai; Liu, Ting; Wang, Haixin; Lin, Zhi; Qian, Jie; Lu, Lingli; Tian, Shengke

2017-05-16

Understanding the strategies that the roots of hyperaccumulating plants use to extract heavy metals from soils is important for optimizing phytoremediation. The rhizosphere characteristics of Sedum alfredii, a hyperaccumulator, were investigated 6 months after it had been planted in weathered field soils contaminated with 5.8 μg of Cd g -1 , 1985.1 μg of Zn g -1 , 667.5 μg of Pb g -1 , and 698.8 μg of Cu g -1 . In contrast with the non-hyperaccumulating ecotype (NHE), the hyperaccumulating ecotype (HE) of S. alfredii was more tolerant to the metals, and higher levels of Cd and Zn accumulated. The HE was characterized by a unique rhizosphere, including extensive root systems, a reduced soil pH, a higher metal bioavailability, and increased rhizomicrobial activity. The bioavailability of metals was significantly correlated with the HE's unique bacterial communities (P heavy metal phytoextraction.

Synergistic effect of co-digestion to enhance anaerobic degradation of catering waste and orange peel for biogas production.

Science.gov (United States)

Anjum, Muzammil; Khalid, Azeem; Qadeer, Samia; Miandad, Rashid

2017-09-01

Catering waste and orange peel were co-digested using an anaerobic digestion process. Orange peel is difficult to degrade anaerobically due to the presence of antimicrobial agents such as limonene. The present study aimed to examine the feasibility of anaerobic co-digestion of catering waste with orange peel to provide the optimum nutrient balance with reduced inhibitory effects of orange peel. Batch experiments were conducted using catering waste as a potential substrate mixed in varying ratios (20-50%) with orange peel. Similar ratios were followed using green vegetable waste as co-substrate. The results showed that the highest organic matter degradation (49%) was achieved with co-digestion of catering waste and orange peel at a 50% mixing ratio (CF4). Similarly, the soluble chemical oxygen demand (sCOD) was increased by 51% and reached its maximum value (9040 mg l -1 ) due to conversion of organic matter from insoluble to soluble form. Biogas production was increased by 1.5 times in CF4 where accumulative biogas was 89.61 m 3 t -1 substrate compared with 57.35 m 3 t -1 substrate in the control after 80 days. The main reason behind the improved biogas production and degradation is the dilution of inhibitory factors (limonene), with subsequent provision of balanced nutrients in the co-digestion system. The tCOD of the final digestate was decreased by 79.9% in CF4, which was quite high as compared with 68.3% for the control. Overall, this study revealed that orange peel waste is a highly feasible co-substrate for anaerobic digestion with catering waste for enhanced biogas production.

Control of waste well casing vent gas from a thermal enhanced oil recovery operation

International Nuclear Information System (INIS)

Peavy, M.A.; Braun, J.E.

1991-01-01

This paper presents an overview of a waste gas treatment system designed to control emissions from thermally enhanced oil recovery wells. This case study discusses the need, design, installation and operations of the system. Oryx Energy Company (Oryx) operates approximately 940 wells in the Midway-Sunset (MWSS) field under casing vapor recovery systems. The emissions collected from well casing vent gas cotaining hydrocarbons and hydrogen sulfide that are collected and processed through casing vapor recovery skids. These skids are composed of condensers, compressors, and pumps that separate fluids from the waste gas stream. The non-condensible gas is then disposed of in incinerators that reduce the hydrocarbon and sulfur emissions into the atmosphere. Approximately 91,000 lbs/day of hydrocarbon and 10,116 lbs/day of sulfur dioxide are removed from the atmosphere from wells contained within these systems operated by Oryx. These hydrocarbons yield approximately 550 barrels of oil per day (BOPD). The system helps manage the pressure differential from the reservoir into each wellbore and contributes to improved ambient air quality in Kern County, California

Effective Strategies for Enhancing Waste Management at University Campuses

Science.gov (United States)

Ebrahimi, Kianoosh; North, Leslie A.

2017-01-01

Purpose: The purpose of this study is to identify and assess the waste management strategies that should be priorities for higher education institutions. The role of policy instruments (i.e. purchasing policies and recycling initiatives) in implementing sustainable zero-waste management programs at higher education institutions was investigated…

Evaluation of the cadmium and lead phytoextraction by castor bean (Ricinus communis L.) in hydroponics

Science.gov (United States)

Niu, Z. X.; Sun, L. N.

2017-06-01

Phytoextraction has been considered as an innovative method to remove toxic metals from soil; higher biomass plants such as castor bean (Ricinus communis L.) have already been considered as a hyperaccumulating candidate. In the present study, castor bean was used to accumulate the cadmium and lead in hydroponic culture, and the root exudates and biomass changes were analyzed. Results demonstrated that ratios of aerial biomass/ root biomass (AW/RW) in treatments declined with concentrations of Cd or Pb. Optical density (OD) at 190 nm and 280 nm of root exudates observed in Cd and Pb treatments were lower than the control. In single Cd or Pb treatments, bioconcentration factors (BCF) of Cd or Pb increased with time and decreased with concentrations, the highest BCFs appeared in Cd5 (14.36) and Pb50 (6.48), respectively. Cd-BCF or Pb-BCF showed positive correlations with AW/RW ratios and OD values, and they were negative correlated with Cd and Pb concentration. Results in this study may supply useful information for phytoremediation of soil contaminated with cadmium and lead in situ.

utilising agricultural waste to enhance food security and conserve

African Journals Online (AJOL)

Sabiiti

becoming increasingly critical to the African farmer, in the wake of evolving ... amounts of agricultural wastes, both at farmer, municipality and city levels. The bulk .... result of the rising interest in organic products such as goat and maize production ... waste burning pollution observed in the town of Vitoria (northern Spain).

Enhancement mechanisms of short-time aerobic digestion for waste activated sludge in the presence of cocoamidopropyl betaine.

Science.gov (United States)

Xia, Siqing; Zhou, Yun; Eustance, Everett; Zhang, Zhiqiang

2017-10-18

Cocoamidopropyl betaine (CAPB), which is a biodegradable ampholytic surfactant, has recently been found to dramatically enhance the aerobic digestion of waste activated sludge (WAS) in short-time aerobic digestion (STAD) systems. Therefore, it is important to understand the mechanisms in which CAPB enhances WAS aerobic digestion performance. Results showed that CAPB could dramatically enhance the solubilization of soluble proteins (PN), polysaccharides (PS), nucleic acids (NA) and humic-like substances (HS) in the STAD system within the initial 2 h. Then PN, PS and NA gradually decreased, while HS showed only minor decease. In addition, CAPB increased the proportion of low MW fractions (biodegradable. Specific oxygen uptake rates and dehydrogenase enzyme activity results indicated that CAPB markedly improved the aerobic microorganism activities. Microbial community analyses and principle coordinate analyses (PCoA) revealed that CAPB increased the proportion of some functional microorganisms, including Proteobacteria, Planctomycetales, Acinetobacter, Pseudomonas and Aeromonas. The changes driven by CAPB could explain the enhanced performance of the STAD system for WAS aerobic treatment.

Enhanced Materials from Nature: Nanocellulose from Citrus Waste

Directory of Open Access Journals (Sweden)

Mayra Mariño

2015-04-01

Full Text Available Nanocellulose is a relatively inexpensive, highly versatile bio-based renewable material with advantageous properties, including biodegradability and nontoxicity. Numerous potential applications of nanocellulose, such as its use for the preparation of high-performance composites, have attracted much attention from industry. Owing to the low energy consumption and the addition of significant value, nanocellulose extraction from agricultural waste is one of the best alternatives for waste treatment. Different techniques for the isolation and purification of nanocellulose have been reported, and combining these techniques influences the morphology of the resultant fibers. Herein, some of the extraction routes for obtaining nanocellulose from citrus waste are addressed. The morphology of nanocellulose was determined by Scanning Electron Microscopy (SEM and Field Emission Scanning Electron Microscopy (FESEM, while cellulose crystallinity indexes (CI from lyophilized samples were determined using solid-state Nuclear Magnetic Resonance (NMR and X-Ray Diffraction (XRD measurements. The resultant nanofibers had 55% crystallinity, an average diameter of 10 nm and a length of 458 nm.

Enhanced materials from nature: nanocellulose from citrus waste.

Science.gov (United States)

Mariño, Mayra; Lopes da Silva, Lucimara; Durán, Nelson; Tasic, Ljubica

2015-04-03

Nanocellulose is a relatively inexpensive, highly versatile bio-based renewable material with advantageous properties, including biodegradability and nontoxicity. Numerous potential applications of nanocellulose, such as its use for the preparation of high-performance composites, have attracted much attention from industry. Owing to the low energy consumption and the addition of significant value, nanocellulose extraction from agricultural waste is one of the best alternatives for waste treatment. Different techniques for the isolation and purification of nanocellulose have been reported, and combining these techniques influences the morphology of the resultant fibers. Herein, some of the extraction routes for obtaining nanocellulose from citrus waste are addressed. The morphology of nanocellulose was determined by Scanning Electron Microscopy (SEM) and Field Emission Scanning Electron Microscopy (FESEM), while cellulose crystallinity indexes (CI) from lyophilized samples were determined using solid-state Nuclear Magnetic Resonance (NMR) and X-Ray Diffraction (XRD) measurements. The resultant nanofibers had 55% crystallinity, an average diameter of 10 nm and a length of 458 nm.

Effective Phytoextraction of Cadmium (Cd) with Increasing Concentration of Total Phenolics and Free Proline in Cannabis sativa (L) Plant Under Various Treatments of Fertilizers, Plant Growth Regulators and Sodium Salt.

Science.gov (United States)

Ahmad, Ayaz; Hadi, Fazal; Ali, Nasir

2015-01-01

The comparative effect of fertilizers (NPK), plant growth regulators (GA3, IAA, Zeatin) and sodium chloride (NaCl) on Cd phytoaccumulation, proline and phenolics production in Cannabis sativa was evaluated. Proline and phenolices were correlated with Cd contents in plant. Cd significantly reduced the plant growth. Fertilizers application (in combination) most significantly increased the growth (19 cm root and 47 cm shoot) on Cd contaminated soil. All treatments increased the Cd contents in plant tissues. This increase was highly significant in fertilizers treated plants (1101, 121 and 544 ppm in roots, stem and leaves respectively). Significantly positive correlation was found between Cd concentration and dry biomass of root (R2=0.7511) and leaves (R2=0.5524). All treatments significantly increased the proline and total phenolics and maximum was recorded in NaCl treated plants followed by fertilizers. Proline was higher in roots while phenolics in leaves. The correlation between proline and phenolics was positive in leaf (R2=0.8439) and root (R2=0.5191). Proline and phenolics showed positive correlation with Cd concentration in plant. Conclusively, fertilizers in combination seem to be the better option for Cd phytoextraction. Further investigation is suggested to study the role of phenolics and proline in Cd phytoextraction.

Enhancement of sludge reduction and methane production by removing extracellular polymeric substances from waste activated sludge.

Science.gov (United States)

Nguyen, Minh Tuan; Mohd Yasin, Nazlina Haiza; Miyazaki, Toshiki; Maeda, Toshinari

2014-12-01

The management of waste activated sludge (WAS) recycling is a concern that affects the development of the future low-carbon society, particularly sludge reduction and biomass utilization. In this study, we investigated the effect of removing extracellular polymeric substances (EPS), which play important roles in the adhesion and flocculation of WAS, on increased sludge disintegration, thereby enhancing sludge reduction and methane production by anaerobic digestion. EPS removal from WAS by ethylenediaminetetraacetic acid (EDTA) significantly enhanced sludge reduction, i.e., 49 ± 5% compared with 27 ± 1% of the control at the end the digestion process. Methane production was also improved in WAS without EPS by 8881 ± 109 CH4 μmol g(-1) dry-weight of sludge. Microbial activity was determined by denaturing gradient gel electrophoresis and real-time polymerase chain reaction, which showed that the hydrolysis and acetogenesis stages were enhanced by pretreatment with 2% EDTA, with a larger methanogenic community and better methane production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Modelling chelate-Induced phytoextraction: functional models predicting bioavailability of metals in soil, metal uptake and shoot biomass

Directory of Open Access Journals (Sweden)

Pasqualina Sacco

2006-06-01

Full Text Available Chelate-induced phytoextraction of heavy metals from contaminated soils requires special care to determine, a priori, the best method of chelate application, in terms of both dose and timing. In fact, the chelate dose must assure the bioavailability of the metal to the plant without increasing leaching risk and giving toxic effects. Three mathematical models are here proposed for usefully interpreting the processes taking place: a increased soil bioavailability of metals by chelants; b metal uptake by plants; c variation in plant biomass. The models are implemented and validated using data from pot and lysimeter trials. Both the chelate dose and the time elapsed since its application affected metal bioavailability and plant response. Contrariwise, the distribution strategy (single vs. split application seems to produce significant differences both in plant growth and metal uptake, but not in soil metal bioavailability. The proposed models may help to understand and predict the chelate dose – effect relationship with less experimental work.

Modelling chelate-Induced phytoextraction: functional models predicting bioavailability of metals in soil, metal uptake and shoot biomass

Directory of Open Access Journals (Sweden)

Pasqualina Sacco

Full Text Available Chelate-induced phytoextraction of heavy metals from contaminated soils requires special care to determine, a priori, the best method of chelate application, in terms of both dose and timing. In fact, the chelate dose must assure the bioavailability of the metal to the plant without increasing leaching risk and giving toxic effects. Three mathematical models are here proposed for usefully interpreting the processes taking place: a increased soil bioavailability of metals by chelants; b metal uptake by plants; c variation in plant biomass. The models are implemented and validated using data from pot and lysimeter trials. Both the chelate dose and the time elapsed since its application affected metal bioavailability and plant response. Contrariwise, the distribution strategy (single vs. split application seems to produce significant differences both in plant growth and metal uptake, but not in soil metal bioavailability. The proposed models may help to understand and predict the chelate dose – effect relationship with less experimental work.

Case studies of corrosion of mixed waste and transuranic waste drums

International Nuclear Information System (INIS)

Kosiewicz, S.T.

1993-01-01

This paper presents three case studies of corrosion of waste drums at the Los Alamos National Laboratory (LANL). Corrosion was not anticipated by the waste generators, but occurred because of subtle chemical or physical mechanisms. In one case, drums of a cemented transuranic (TRU) sludge experienced general and pitting corrosion. In the second instance, a chemical from a commercial paint stripper migrated from its primary containment drums to chemically attack overpack drums made of mild carbon steel. In the third case, drums of mixed low level waste (MLLW) soil corroded drum packaging even though the waste appeared to be dry when it was placed in the drums. These case studies are jointly discussed as ''lessons learned'' to enhance awareness of subtle mechanisms that can contribute to the corrosion of radioactive waste drums during interim storage

Enhancement of the recycling of waste Ni-Cd and Ni-MH batteries by mechanical treatment.

Science.gov (United States)

Huang, Kui; Li, Jia; Xu, Zhenming

2011-06-01

A serious environmental problem was presented by waste batteries resulting from lack of relevant regulations and effective recycling technologies in China. The present work considered the enhancement of waste Ni-Cd and Ni-MH batteries recycling by mechanical treatment. In the process of characterization, two types of waste batteries (Ni-Cd and Ni-MH batteries) were selected and their components were characterized in relation to their elemental chemical compositions. In the process of mechanical separation and recycling, waste Ni-Cd and Ni-MH batteries were processed by a recycling technology without a negative impact on the environment. The technology contained mechanical crushing, size classification, gravity separation, and magnetic separation. The results obtained demonstrated that: (1) Mechanical crushing was an effective process to strip the metallic parts from separators and pastes. High liberation efficiency of the metallic parts from separators and pastes was attained in the crushing process until the fractions reached particle sizes smaller than 2mm. (2) The classified materials mainly consisted of the fractions with the size of particles between 0.5 and 2mm after size classification. (3) The metallic concentrates of the samples were improved from around 75% to 90% by gravity separation. More than 90% of the metallic materials were separated into heavy fractions when the particle sizes were larger than 0.5mm. (4) The size of particles between 0.5 and 2mm and the rotational speed of the separator between 30 and 60 rpm were suitable for magnetic separation during industrial application, with the recycling efficiency exceeding 95%. Copyright © 2011 Elsevier Ltd. All rights reserved.

Comparing two enhancing methods for improving kitchen waste anaerobic digestion: bentonite addition and autoclaved de-oiling pretreatment

DEFF Research Database (Denmark)

Zhang, Duojiao; Duan, Na; Tian, Hailin

2018-01-01

The effects of different enhancement methods, including adding bentonite (1.25%, w/w, wet substrate) and autoclaved de-oiling pretreatment (121 °C, 30 minutes), on the anaerobic digestion of kitchen waste (KW) were comparably studied. Mesophilic continuous stirred tank reactors were used under...... different organic loading rates (OLRs) of 1.11 to 1.84 gVS (volatile solid)L−1d−1 and two different hydraulic retention times (HRTs) (20 d and 25 d). In this study, two enhancement methods and extending HRT could prevent volatile fatty acids (VFA) accumulation and obtain a high methane production at low OLR...... design and process evaluation of a CSTR biogas plant treating with KW based on the laboratory experiment was stated....

The Importance of Building and Enhancing Worldwide Industry Cooperation in the Areas of Radiological Protection, Waste Management and Decommissioning

International Nuclear Information System (INIS)

Saint-Pierre, S.

2006-01-01

The slow or stagnant rate of nuclear power generation development in many developed countries over the last two decades has resulted in a significant shortage in the population of mid-career nuclear industry professionals. This shortage is even more pronounced in some specific areas of expertise such as radiological protection, waste management and decommissioning. This situation has occurred at a time when the renaissance of nuclear power and the globalization of the nuclear industry are steadily gaining momentum and when the industry's involvement in international and national debates in these three fields of expertise (and the industry's impact on these debates) is of vital importance. This paper presents the World Nuclear Association (WNA) approach to building and enhancing worldwide industry cooperation in radiological protection, waste management and decommissioning, which is manifested through the activities of the two WNA working groups on radiological protection (RPWG) and on waste management and decommissioning (WM and DWG). This paper also briefly describes the WNA's participatory role, as of summer 2005, in the International Atomic Energy Agency (IAEA) standard development committees on radiation safety (RASSC), waste safety (WASSC) and nuclear safety (NUSSC). This participation provides the worldwide nuclear industry with an opportunity to be part of IAEA's discussions on shaping changes to the control regime of IAEA safety standards. The review (and the prospect of a revision) of IAEA safety standards, which began in October 2005, makes this WNA participation and the industry ' s involvement at the national level timely and important. All of this excellent industry cooperation and team effort is done through 'collegial' exchanges between key industry experts, which help tackle important issues more effectively. The WNA is continuously looking to enhance its worldwide industry representation in these fields of expertise through the RPWG and WM and DWG

The importance of building and enhancing worldwide industry cooperation in the areas of radiological protection, waste management and decommissioning

International Nuclear Information System (INIS)

Saint-Pierre, S.

2006-01-01

The slow or stagnant rate of nuclear power generation development in many developed countries over the last two decades has resulted in a significant shortage in the population of mid-career nuclear industry professionals. This shortage is even more pronounced in some specific areas of expertise such as radiological protection, waste management and decommissioning. This situation has occurred at a time when the renaissance of nuclear power and the globalization of the nuclear industry are steadily gaining momentum and when the industry's involvement in international and national debates in these three fields of expertise (and the industry's impact on these debates) is of vital importance. This paper presents the World Nuclear Association (WNA) approach to building and enhancing worldwide industry cooperation in radiological protection, waste management and decommissioning, which is manifested through the activities of the two WNA working groups on radiological protection (RPWG) and on waste management and decommissioning (WM and DWG). This paper also briefly describes the WNA's participatory role, as of Summer 2005, in the International Atomic Energy Agency (IAEA) standard development committees on radiation safety (RASSC), waste safety (WASSC) and nuclear safety (NUSSC). This participation provides the worldwide nuclear industry with an opportunity to be part of IAEA's discussions on shaping changes to the control regime of IAEA safety standards. The review (and the prospect of a revision) of IAEA safety standards, which began in October 2005, makes this WNA participation and the industry's involvement at the national level timely and important. All of this excellent industry cooperation and team effort is done through 'collegial' exchanges between key industry experts, which help tackle important issues more effectively. The WNA is continuously looking to enhance its worldwide industry representation in these fields of expertise through the RPWG and WM and DWG

Mobile/Modular Deployment Project-Enhancing Efficiencies within the National Transuranic Waste Program

International Nuclear Information System (INIS)

Triay, I.R.; Basabilvazo, G.B.; Countiss, S.; Moody, D.C.; Behrens, R.G.; Lott, S.A.

2002-01-01

In 1999, the National Transuranic (TRU) Waste Program (NTP) achieved two significant milestones. First, the Waste Isolation Plant (WIPP) opened in March for the permanent disposal of TRU waste generated by, and temporarily stored at, various sites supporting the nation's defense programs. Second, the Hazardous Waste Facility Permit, issued by the New Mexico Environment Department, for WIPP became effective in November. While the opening of WIPP brought to closure a number of scientific, engineering, regulatory, and political challenges, achieving this major milestone led to a new set of challenges-how to achieve the Department of Energy's (DOE's) NTP end-state vision: All TRU waste from DOE sites scheduled for closure is removed All legacy TRU waste from DOE sites with an ongoing nuclear mission is disposed 0 All newly generated TRU waste is disposed as it is generated The goal is to operate the national TRU waste program safely, cost effectively, in compliance with applicable regulations and agreements, and at full capacity in a fully integrated mode. The existing schedule for TRU waste disposition would achieve the NTP vision in 2034 at an estimated life-cycle cost of $16B. The DOE's Carlsbad Field Office (CBFO) seeks to achieve this vision early-by at least 10 years- while saving the nation an estimated $48 to $6B. CBFO's approach is to optimize, or to make as functional as possible, TRU waste disposition. That is, to remove barriers that impede waste disposition, and increase the rate and cost efficiency of waste disposal at WIPP, while maintaining safety. The Mobile/Modular Deployment Project (MMDP) is the principal vehicle for implementing DOE's new commercial model of using best business practices of national authorization basis, standardization, and economies of scale to accelerate the completion of WIPP's mission. The MMDP is one of the cornerstones of the National TRU Waste System Optimization Project (1). The objective of the MMDP is to increase TRU

Hazardous waste database: Waste management policy implications for the US Department of Energy's Environmental Restoration and Waste Management Programmatic Environmental Impact Statement

International Nuclear Information System (INIS)

Lazaro, M.A.; Policastro, A.J.; Antonopoulos, A.A.; Hartmann, H.M.; Koebnick, B.; Dovel, M.; Stoll, P.W.

1994-01-01

The hazardous waste risk assessment modeling (HaWRAM) database is being developed to analyze the risk from treatment technology operations and potential transportation accidents associated with the hazardous waste management alternatives. These alternatives are being assessed in the Department of Energy's Environmental Restoration and Waste Management Programmatic Environmental Impact Statement (EM PEIS). To support the risk analysis, the current database contains complexwide detailed information on hazardous waste shipments from 45 Department of Energy installations during FY 1992. The database is currently being supplemented with newly acquired data. This enhancement will improve database information on operational hazardous waste generation rates, and the level and type of current on-site treatment at Department of Energy installations

Improving radioactive waste management: an overview of the Environmental Protection Agency's low-activity waste effort.

Science.gov (United States)

Schultheisz, Daniel J; Czyscinski, Kenneth S; Klinger, Adam D

2006-11-01

Radioactive waste disposal in the United States is marked by a fragmented regulatory system, with requirements that often focus on the origin or statutory definition of the waste, rather than the hazard of the material in question. It may be possible to enhance public protection by moving toward a system that provides disposal options appropriate for the hazard presented by the waste in question. This paper summarizes aspects of an approach focusing on the potential use, with appropriate conditions, of Resource Conservation and Recovery Act Subtitle-C hazardous waste landfills for disposal of "low-activity" wastes and public comments on the suggested approach.

Solidification of highly active wastes

International Nuclear Information System (INIS)

Morris, J.B.

1984-11-01

Final reports are presented on work on the following topics: glass technology; enhancement of off-gas aerosol collection; formation and trapping of volatile ruthenium; volatilisation of caesium, technetium and tellurium in high-level waste vitrification; deposition of ruthenium; and calcination of high-level waste liquors. (author)

Advanced air/flue gas staging based on CFD modelling for enhanced combustion and burnout in a waste-wood fired boiler

DEFF Research Database (Denmark)

Rajh, Boštjan; Yin, Chungen; Samec, Niko

2017-01-01

The paper presents the impacts of the jet momentum, position and orientation of air and Recycled Flue Gas (RFG) streams on the performance of a grate-fired boiler burning waste wood via a comprehensive CFD-based parametric study. It is found that the air and RFG jets can be optimized to enhance m...

Determination of Intrinsic Permeability for Packed Waste of Indonesian Solid Waste

Directory of Open Access Journals (Sweden)

Benno Rahardyan

2010-11-01

Full Text Available Gas permeability and intrinsic permeability are the major parameters to promote aeration for packed waste. The objectives of this research are to identify physical parameters of gas transfer from a various type of packed wastes and examine ventilation design theory for landfill to enhance waste stabilization. Method to determine value of gas permeability and intrinsic permeability for packed waste is by flushing the packed column containing various type and physical characteristics of wastes with an air pump. Permeability was calculated by measuring pressure gradient on sampling points of the column using inclined manometer at distance 10 cm, 23 cm, 46 cm, 69 cm, 92 cm and 115 cm from origin. Gas permeability is specifically relied on physical parameters of wastes as follows, density, moisture content, particle size and gas velocity on the surface of compacted waste layer. Compost has finer pore structure and smaller pore size than leaves as well as mixed organic (65% and inorganic wastes (35%. The experiment found the intrinsic permeability of leaves waste are in the order of 10-11 to 10-8 m2, 10-11 to 10-9 m2 for compost and 10-9 m2 for mixed organic (65% and inorganic wastes (35%.

Toward integrated design of waste management technologies

International Nuclear Information System (INIS)

Carnes, S.A.; Wolfe, A.K.

1994-01-01

Implementation of waste management technologies has been hindered by the intervention of diverse interests. Relying on a perceived history of inadequate and improper management, operations, and technological design, critics have stymied the implementation of scientifically and governmentally approved technologies and facilities, leading to a critical shortage of hazardous, mixed, and radioactive waste management capacity. The research and development (R ampersand D) required to identify technologies that are simultaneously (1) scientifically valid, (2) economically sound, and (3) publicly acceptable must necessarily address, in an integrated and interdisciplinary manner, these three criteria and how best to achieve the integration of stakeholders early in the technology implementation process (i.e., R ampersand D, demonstration, and commercialization). The goal of this paper is to initiate an identification of factors likely to render radioactive and hazardous waste management technologies publicly acceptable and to provide guidance on how technological R ampersand D might be revised to enhance the acceptability of alternative waste management technologies. Principal among these factors are the equitable distribution of costs, risks, and benefits of waste management policies and technologies, the equitable distribution of authority for making waste management policy and selecting technologies for implementation, and the equitable distribution of responsibility for resolving waste management problems. Stakeholder participation in assessing the likely distribution of these factors and mitigative mechanisms to enhance their equitable distribution, together with stakeholder participation in policy and technology R ampersand D, as informed by stakeholder assessments, should enhance the identification of acceptable policies and technologies

Effect of EDTA and Citric Acid on Phytoextraction of Copper and Zinc from a Naturally Contaminated Soil by Maize (Zea mays L. Cultivars

Directory of Open Access Journals (Sweden)

A. Taheripur

2016-09-01

Full Text Available Introduction: Mining and smelting activities have contributed to increasing levels of copper (Cu and zinc (Zn in soils around of Sarcheshmeh copper mine (Kerman, Iran. Soil chemical analysis showed that the available of Cu and Zn (extracted with DTPA-TEA were 260.1 and 9.2 mg kg-1 soil, respectively. Phytoextraction is one of the most popular and useful phytoremediation techniques for removal of heavy metals from polluted soils. For chemically-assisted phytoextraction, different chelating agents such as EDTA and citric acid are applied to soil to increase the availability of heavy metals in soil for uptake by plants. A pot experiment was conducted to elucidate the performance of chelating agents addition in improving phytoextraction of Cu and zinc Zn from a naturally contaminated soil by maize (Zea mays L. cultivars. Materials and Methods: A factorial experiment in a completely randomized design was carried out bythree factors of chelate type, chelate concentrations and maize cultivars with three replications in 2012 at ShahreKord University. Chelating agents were Ethylene Diamine Tetra Acetic Acid (EDTA and citric acid (CA. They were applied in concentration levels of 0, 0.75 and 1.5 mmole kg-1 soil with irrigation water. The three maize cultivars used were single cross 704 (SC-704, three v cross 647 (TVC-647, and single cross 677 (SC-677. The pots were 23 cm in diameter and 23 cm deep, and were filled with 4 kg of a silty loam, calcareous soil taken from the surface layer of Sarcheshmeh copper mine area. Maize plant s was grown under greenhouse conditions over 90 days. After the harvest, soil available Cu and Zn contents (extracted with DTPA-TEA were determined by atomic absorption spectrophotometry (AAS. Plant samples (shoot and root were dried for 48 h at 70ºC to determine their dry matter content (yield. Total Cu and Zn concentrations in root and shoot of maize were measured after digestion plant samples by AAS method. The shoot and root

Thiosulphate assisted phytoextraction of mercury contaminated soils at the Wanshan Mercury Mining District, Southwest China

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J. Wang

2013-10-01

Full Text Available Wanshan, known as the “Mercury Capital” of China, is located in the Southwest of China. Due to the extensive mining and smelting works in the Wanshan area, the local ecosystem has been serious contaminated with mercury. In the present study, a number of soil samples were taken from the Wanshan mercury mining area and the mercury fractionations in soils were analyzed using sequential extraction procedure technique. The obtained results showed that the dominate mercury fractions (represent 95% of total mercury were residual and organic bound mercury. A field trial was conducted in a mercury polluted farmland at the Wanshan mercury mine. Four plant species Brassica juncea Czern. et Coss.var. ASKYC (ASKYC, Brassica juncea Czern. et Coss.var.DPDH (DPDH, Brassica juncea Czern. et Coss.var.CHBD(CHBD, Brassica juncea Czern. et Coss.var.LDZY (LDZY were tested their ability to extract mercury from soil with thiosulphate amendment. The results indicated that the mercury concentration in the roots and shoots of the four plants were significantly increased with thiosulphate treatment. The mercury phytoextraction yield of ASKYC, DPDH, CHBD and LDZY were 92, 526, 294 and 129 g/ha, respectively

Thiosulphate assisted phytoextraction of mercury contaminated soils at the Wanshan Mercury Mining District, Southwest China

Directory of Open Access Journals (Sweden)

J Wang

2013-10-01

Full Text Available Wanshan, known as the “Mercury Capital” of China, is located in the Southwest of China. Due to the extensive mining and smelting works in the Wanshan area, the local ecosystem has been serious contaminated with mercury. In the present study, a number of soil samples were taken from the Wanshan mercury mining area and the mercury fractionations in soils were analyzed using sequential extraction procedure technique. The obtained results showed that the dominate mercury fractions (represent 95% of total mercury were residual and organic bound mercury. A field trial was conducted in a mercury polluted farmland at the Wanshan mercury mine. Four plant species Brassica juncea Czern. et Coss.var. ASKYC (ASKYC, Brassica juncea Czern. et Coss.var.DPDH (DPDH, Brassica juncea Czern. et Coss.var.CHBD(CHBD, Brassica juncea Czern. et Coss.var.LDZY (LDZY were tested their ability to extract mercury from soil with thiosulphate amendment. The results indicated that the mercury concentration in the roots and shoots of the four plants were significantly increased with thiosulphate treatment. The mercury phytoextraction yield of ASKYC, DPDH, CHBD and LDZY were 92, 526, 294 and 129 g/ha, respectively.

Solidification of highly active wastes

International Nuclear Information System (INIS)

Morris, J.B.

1986-07-01

This document contains the annual reports for the contracts: (A) Glass Technology; (B) Calcination of Highly Active Waste Liquors; (C) Formation and Trapping of Volatile Ruthenium; (D) Deposition of Ruthenium; (E) Enhancement of Off-Gas Aerosol Collection; (F) Volatilisation of Cs, Tc and Te in High Level Waste Vitrification. (author)

Anti-Aging Potential of Phytoextract Loaded-Pharmaceutical Creams for Human Skin Cell Longetivity

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Saima Jadoon

2015-01-01

Full Text Available The exposure to ultraviolet radiations (UVR is the key source of skin sunburn; it may produce harmful entities, reactive oxygen species (ROS, leading to aging. The skin can be treated and protected from the injurious effects of ROS by using various pharmaceutical formulations, such as cream. Cream can be loaded with antioxidants to quench ROS leading to photo-protective effects. Moreover, modern medicines depend on ethnobotanicals for protection or treatment of human diseases. This review article summarizes various in vivo antioxidant studies on herbal creams loaded with phyto-extracts. These formulations may serve as cosmeceuticals to protect skin against injurious effects of UVR. The botanicals studied for dermatologic use in cream form include Acacia nilotica, Benincasa hispida, Calendula officinalis, Camellia sinensis, Camellia sinensis, Nelumbo nucifera, Capparis decidua, Castanea sativa, Coffea arabica, Crocus sativus, Emblica officinalis Gaertn, Foeniculum vulgare, Hippophae rhamnoides, Lithospermum erythrorhizon, Malus domestica, Matricaria chamomilla L., Moringa oleifera, Morus alba, Ocimum basilicum, Oryza sativa, Polygonum minus, Punica granatum, Silybum marianum, Tagetes erecta Linn., Terminalia chebula, Trigonella foenum-graecum, and Vitis vinifera. The observed anti-aging effects of cream formulations could be an outcome of a coordinating action of multiple constituents. Of numerous botanicals, the phenolic acids and flavonoids appear effective against UVR-induced damage; however the evidence-based studies for their anti-aging effects are still needed.

Phytoextraction of rare earth elements in herbaceous plant species growing close to roads.

Science.gov (United States)

Mikołajczak, Patrycja; Borowiak, Klaudia; Niedzielski, Przemysław

2017-06-01

The aim of study was to determine the phytoextraction of rare earth elements (REEs) to roots, stems and leaves of five herbaceous plant species (Achillea millefolium L., Artemisia vulgaris L., Papaver rhoeas L., Taraxacum officinale AND Tripleurospermum inodorum), growing in four areas located in close proximity to a road with varied traffic intensity. Additionally, the relationship between road traffic intensity, REE concentration in soil and the content of these elements in plant organs was estimated. A. vulgaris and P. rhoeas were able to effectively transport REEs in their leaves, independently of area collection. The highest content of REEs was observed in P. rhoeas leaves and T. inodorum roots. Generally, HREEs were accumulated in P. rhoeas roots and leaves and also in the stems of T. inodorum and T. officinale, whereas LREEs were accumulated in T. inodorum roots and T. officinale stems. It is worth underlining that there was a clear relationship between road traffic intensity and REE, HREE and LREE concentration in soil. No positive correlation was found between the concentration of these elements in soil and their content in plants, with the exception of T. officinale. An effective transport of REEs from the root system to leaves was observed, what points to the possible ability of some of the tested plant species to remove REEs from soils near roads.

Towards a sustainable paradigm of waste-to-energy process: Enhanced anaerobic digestion of sludge with woody biochar

Energy Technology Data Exchange (ETDEWEB)

Shen, Yanwen; Linville, Jessica L.; Ignacio-de Leon, Patricia Anne A.; Schoene, Robin P.; Urgun-Demirtas, Meltem

2016-11-01

This study presents an integrated waste-to-energy process, using two waste streams, sludge generated from the municipal wastewater treatment plants (WWTPs) and biochar generated from the biomass gasification systems, to produce fungible biomethane and nutrient-rich digestate with fertilizer value. Two woody biochar, namely pinewood (PBC) and white oak biochar (WOBC) were used as additives during anaerobic digestion (AD) of WWTP sludge to enhance methane production at mesophilic and thermophilic temperatures. The PBC and WOBC have porous structure, large surface area and desirable chemical properties to be used as AD amendment material to sequester CO2 from biogas in the digester. The biochar-amended digesters achieved average methane content in biogas of up to 92.3% and 79.0%, corresponding to CO2 sequestration by up to 66.2% and 32.4% during mesophilic and thermophilic AD, respectively. Biochar addition enhanced process stability by increasing the alkalinity, but inhibitory effects were observed at high dosage. It also alleviated free ammonia inhibition by up to 10.5%. The biochar-amended digesters generated digestate rich in macro- and micronutrients including K (up to 300 m/L), Ca (up to 750 mg/L), Mg (up to 1800 mg/L) and Fe (up to 390 mg/L), making biochar-amended digestate a potential alternative used as agricultural lime fertilizer.

The Importance of Enhancing Worldwide Industry Cooperation in Radiological Protection, Waste Management and Decommissioning - Views from the Global Nuclear Industry

International Nuclear Information System (INIS)

Saint-Pierre, S.

2008-01-01

The slow or stagnant rate of nuclear power generation development in many developed countries over the last two decades has resulted in a significant shortage in the population of mid-career nuclear industry professionals. This shortage is even more pronounced in some specific areas of expertise such as radiological protection, waste management and decommissioning. This situation has occurred at a time when the renaissance of nuclear power and the globalization of the nuclear industry are steadily gaining momentum and when the industry's involvement in international and national debates in these three fields of expertise (and the industry's impact on these debates) is of great relevance.This paper presents the World Nuclear Association (WNA) approach to building and enhancing worldwide industry cooperation in radiological protection, waste management and decommissioning, which is manifested through the activities of the two WNA working groups on radiological protection (RPWG) and on waste management and decommissioning (WM and DWG). This paper also briefly describes the WNA's participatory role, as of Summer 2005, in the International Atomic Energy Agency (IAEA) standard development committees on radiation safety (RASSC), waste safety (WASSC) and nuclear safety (NUSSC). This participation provides the worldwide nuclear industry with an opportunity to be part of IAEA's discussions on shaping changes to the control regime of IAEA safety standards. The review (and the prospect of a revision) of IAEA safety standards, which began in October 2005, makes this WNA participation and the industry's involvement at the national level timely and important. All of this excellent industry cooperation and team effort is done through 'collegial' exchanges between key industry experts, which help tackle important issues more effectively. The WNA is continuously looking to enhance its worldwide industry representation in these fields of expertise through the RPWG and WM and DWG

Enhancement of insulating properties of brick clay by renewable agricultural wastes

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Viktor Bánhidi

2008-12-01

Full Text Available The use of agricultural wastes (byproducts in various segments of brick and tile industry is increasing continuously. These additives, which are previously mixed into the raw or compound clay, start to ignite during the firing process, providing extra thermal energy inside the product and decreasing the required external energy need. Besides this effect, the combustion of additives increases the porosity of the final product resulting in enhanced thermal insulation properties. In this paper the effect of some common agricultural wastes (sawdust, rice-peel and seed-shell on the thermal properties of brick clay products was investigated. The brick samples were prepared from the mixture of the yellow and gray clay in the ratio of 4:1, water content was between 15.57-16.67 wt.% and the pore-forming additives in concentrations 0, 4 and 7 wt.%. To measure the steady state thermal conductivity of the clay mixtures, samples with dimensions of 300×300×50 mm were prepared. Drying and firing were performed using the industrial partner’s standard procedures. Precise thermal conductivity data was measured, using a RAPID‑K type static thermal conductivity instrument. The results showed that increasing the quantity of agricultural byproducts in the clay mixture significantly decreases the thermal conductivity of the final products, while only a minor reduction in the mechanical strength was observed. It was found that the most efficient byproduct additive was the sunflower seed‑shell. With the addition of only 7 wt.% seed‑shell to the basic clay the thermal conductivity decreased from 0,27 W/m·K to 0,17 W/m·K (i.e. ~36%.

Development of a Curriculum Management Process by Applying Lean Concept for Waste Elimination to Enhance Curriculum Implementation of Primary School Teacher

Science.gov (United States)

Chitrangsan, Nadrudee; Sawekngam, Wichai; Thongthew, Sumlee

2015-01-01

This research aims to study and develop a curriculum management process by applying Lean concept for waste elimination to enhance curriculum implementation of primary school teacher. This study was conducted with a focus on qualitative data collection by dividing into 2 phases, including (1) analyze and synthesize relevant notions, theories,…

Effects of Cd, Pb, Zn, Cu-resistant endophytic Enterobacter sr CBSB1 and Rhodotorula sp. CBSB79 on the growth and phytoextraction of Brassica plants in multimetal contaminated soils.

Science.gov (United States)

Wang, Wenfeng; Deng, Zujun; Tan, Hongming; Cao, Lixiang

2013-01-01

To survey the effects of endophytic Enterobacter sp. CBSB1 and Rhodotorula sp. CBSB79 resistant to Cd2+, Pb2+, Zn2+, and Cu2+ on the growth and phytoextraction of Brassica, the endophytes were isolated by surface- sterilized methods and characterized. The CBSB1 significantly increased 44.2% of the dry weight of Brassica napus in the multimetal contaminated soil (P Rhodotorula sp CBSB79 showed higher potentials to improve extraction efficacy of Cd, Pb, Zn, and Cu by Brassica seedlings in the field.

Enhanced Bio-Ethanol Production from Industrial Potato Waste by Statistical Medium Optimization

OpenAIRE

Izmirlioglu, Gulten; Demirci, Ali

2015-01-01

Industrial wastes are of great interest as a substrate in production of value-added products to reduce cost, while managing the waste economically and environmentally. Bio-ethanol production from industrial wastes has gained attention because of its abundance, availability, and rich carbon and nitrogen content. In this study, industrial potato waste was used as a carbon source and a medium was optimized for ethanol production by using statistical designs. The effect of various medium componen...

An innovative treatment method for an aqueous waste from the enhanced oil recovery process

International Nuclear Information System (INIS)

Alimahmoodi, M.; Mulligan, C.N.

2009-01-01

Anaerobic treatment was evaluated to determine its effectiveness in treating a waste stream from the process of Enhanced Oil Recovery (EOR) to remove solubilized CO 2 (98%) and petroleum hydrocarbons (83%) using formate (2 g/L) and sucrose (2.5 g/L) as electron donors in two consecutive reactors. The method of evolutionary operation (EVOP) factorial design was applied to optimize the system and the net energy ratio (NER) of 3.7 was calculated for the system which showed a sustainable biogas production. This method is less complex than other competitive methods, and in addition to its low energy requirements, it can produce CH 4 from CO 2 as a clean source of energy. (author)

Assessing green waste route by using Network Analysis

Science.gov (United States)

Hasmantika, I. H.; Maryono, M.

2018-02-01

Green waste, such as waste from park need treat proper. One of the main problems of green waste management is how to design optimum collection. This research aims to determine the optimum green waste collection by determining optimum route among park. The route optimum was assessed by using network analysis method. And the region five of Semarang city’s park within 20 parks in chose as case study. To enhancing recycle of green waste, three scenarios of treatment are proposed. Scenario 1 used one integrated treatment facility as terminal for enhancing recycle of green waste, Scenario 2 used two sites and scenario 3 used three sites. According to the assessment, the length of route of scenario 1 is 36.126 km and the time for collection estimated is 46 minutes. In scenario 2, the length of route is 36.471 km with a travel time is 47 minutes. The length of scenario three is 46.934 km and the time of collection is 60 minutes.

Organic destruction to enhance the separation of strontium in radioactive wastes

International Nuclear Information System (INIS)

Schmidt, A.J.; Elmore, M.R.; Orth, R.J.; Jones, E.O.; Zacher, A.H.; Hart, T.R.; Neuenschwander, G.G.; Poshusta, J.C.

1994-01-01

A low-temperature (300 C to 375 C) hydrothermal organic destruction process is being evaluated to help facilitate the removal of complexed radioactive species from bulk liquid components in hanford tank waste. The work focuses on hydrothermal processing to destroy organic compounds that contribute to waste safety issues and organic complexants that promote the solubility of radioactive constituents such as 90 Sr and 241 Am. For the studies discussed here, testing was conducted using a nonradioactive Hanford tank waste simulant. The relative destruction rates of a variety of organic compounds known to be present in Hanford tank waste were evaluated. In addition, the tendency for these organic compounds to complex strontium and the effect of hydrothermal treatment on strontium removal were investigated

Organic destruction to enhance the separation of strontium in radioactive wastes

International Nuclear Information System (INIS)

Schmidt, A.J.; Elmore, M.R.; Orth, R.J.; Jones, E.O.; Zacher, A.H.; Hart, T.R.; Neuenschwander, G.G.; Poshusta, J.C.

1994-10-01

A low-temperature (300 C to 375 C) hydrothermal organic destruction process is being evaluated to help facilitate the removal of complexed radioactive species from bulk liquid components in Hanford tank waste. The work focuses on hydrothermal processing to destroy organic compounds that contribute to waste safety issues and organic complexants that promote the solubility of radioactive constituents such as 9O Sr and 241 Am. For the studies discussed here, testing was conducted using a nonradioactive Hanford tank waste simulant. The relative destruction rates of a variety of organic compounds known to be present in Hanford tank waste were evaluated. In addition, the tendency for these organic compounds to complex strontium and the effect of hydrothermal treatment on strontium removal were investigated

Innovative hazardous waste treatment technology

International Nuclear Information System (INIS)

Freeman, H.M.; Sferra, P.R.

1990-01-01

This book contains 21 various biodegradation techniques for hazardous waste treatment. Topics include: cyclic vertical water table movement for enhancement of in situ biodegradation of diesel fuel; enhanced biodegradation of petroleum hydrocarbons; and evaluation of aeration methods to bioremediate fuel-contaminated soils

US DOE Initiated Performance Enhancements to the Hanford Waste Treatment and Immobilization Plant (WTP) Low-activity Waste Vitrification (LAW) System

International Nuclear Information System (INIS)

Hamel, William F.; Gerdes, Kurt D.; Holton, Langdon K.; Pegg, Ian L.; Bowen, Brad W.

2006-01-01

The U.S Department of Energy Office of River Protection (DOE-ORP) is constructing a Waste Treatment and Immobilization Plant (WTP) for the treatment and vitrification of underground tank wastes stored at the Hanford Site in Washington State. The WTP comprises four major facilities: a pretreatment facility to separate the tank waste into high level waste (HLW) and low-activity waste (LAW) process streams, a HLW vitrification facility to immobilize the HLW fraction; a LAW vitrification facility to immobilize the LAW fraction, and an analytical laboratory to support the operations of all four treatment facilities. DOE has established strategic objectives to optimize the performance of the WTP facilities and the LAW and HLW waste forms to reduce the overall schedule and cost for treatment and vitrification of the Hanford tank wastes. This strategy has been implemented by establishing performance expectations in the WTP contract for the facilities and waste forms. In addition, DOE, as owner-operator of the WTP facilities, continues to evaluate (1) the design, to determine the potential for performance above the requirements specified in the WTP contract; and (2) improvements in production of the LAW and HLW waste forms. This paper reports recent progress directed at improving production of the LAW waste form. DOE's initial assessment, which is based on the work reported in this paper, is that the capacity of the WTP LAW vitrification facility can be increased by a factor of 2 to 4 with a combination of revised glass formulations, modest increases in melter glass operating temperatures, and a second-generation LAW melter with a larger surface area. Implementing these improvements in the LAW waste immobilization capability can benefit the LAW treatment mission by reducing both processing time and cost

Optimal design of advanced distillation configuration for enhanced energy efficiency of waste solvent recovery process in semiconductor industry

International Nuclear Information System (INIS)

Chaniago, Yus Donald; Minh, Le Quang; Khan, Mohd Shariq; Koo, Kee-Kahb; Bahadori, Alireza; Lee, Moonyong

2015-01-01

Highlights: • Thermally coupled distillation process is proposed for waste solvent recovery. • A systematic optimization procedure is used to optimize distillation columns. • Response surface methodology is applied to optimal design of distillation column. • Proposed advanced distillation allows energy efficient waste solvent recovery. - Abstract: The semiconductor industry is one of the largest industries in the world. On the other hand, the huge amount of solvent used in the industry results in high production cost and potential environmental damage because most of the valuable chemicals discharged from the process are incinerated at high temperatures. A distillation process is used to recover waste solvent, reduce the production-related costs and protect the environment from the semiconductor industrial waste. Therefore, in this study, a distillation process was used to recover the valuable chemicals from semiconductor industry discharge, which otherwise would have been lost to the environment. The conventional sequence of distillation columns, which was optimized using the Box and sequential quadratic programming method for minimum energy objectives, was used. The energy demands of a distillation problem may have a substantial influence on the profitability of a process. A thermally coupled distillation and heat pump-assisted distillation sequence was implemented to further improve the distillation performance. Finally, a comparison was made between the conventional and advanced distillation sequences, and the optimal conditions for enhancing recovery were determined. The proposed advanced distillation configuration achieved a significant energy saving of 40.5% compared to the conventional column sequence

Organic waste treatment with organically modified clays

International Nuclear Information System (INIS)

Evans, J.C.; Pancoski, S.E.; Alther, G.

1989-01-01

The use of organically modified clays in hazardous waste management applications offers a significant new and untapped potential. These clays may be used in the stabilization of organic wastes and organically contaminated soils, for waste water treatment, for oil spill control, for liner systems beneath fuel oil storage tanks, and as a component within liner systems of hazardous waste storage treatment and disposal facilities. Organically modified clays (organophilic clays) may be employed in each of these systems to adsorb organic waste constituents, enhancing the performance of the applications

Enhanced removal of nitrate from water using amine-grafted agricultural wastes

Energy Technology Data Exchange (ETDEWEB)

Kalaruban, Mahatheva; Loganathan, Paripurnanda [Faculty of Engineering, University of Technology Sydney (UTS), P.O. Box 123, Broadway, NSW 2007 (Australia); Shim, W.G. [Faculty of Engineering, University of Technology Sydney (UTS), P.O. Box 123, Broadway, NSW 2007 (Australia); Department of Polymer Science and Engineering, Sunchon National University, 255 Jungang-ro, Suncheon, Jeollanam-do (Korea, Republic of); Kandasamy, Jaya; Ngo, H.H. [Faculty of Engineering, University of Technology Sydney (UTS), P.O. Box 123, Broadway, NSW 2007 (Australia); Vigneswaran, Saravanamuthu, E-mail: s.vigneswaran@uts.edu.au [Faculty of Engineering, University of Technology Sydney (UTS), P.O. Box 123, Broadway, NSW 2007 (Australia)

2016-09-15

Adsorption using low-cost adsorbents is a favourable water treatment method for the removal of water contaminants. In this study the enhanced removal of nitrate, a contaminant at elevated concentration affecting human health and causing eutrophication of water, was tested using chemically modified agricultural wastes as adsorbents. Batch and fixed-bed adsorption studies were performed on corn cob and coconut copra that were surface modified by amine-grafting to increase the surface positive charges. The Langmuir nitrate adsorption capacities (mg N/g) were 49.9 and 59.0 for the amine-grafted (AG) corn cob and coconut copra, respectively at pH 6.5 and ionic strength 1 × 10{sup −3} M NaCl. These values are higher than those of many commercially available anion exchange resins. Fixed-bed (15-cm height) adsorption capacities (mg N/g) calculated from the breakthrough curves were 15.3 and 18.6 for AG corn cob and AG coconut copra, respectively, for an influent nitrate concentration 20 mg N/L at a flow velocity 5 m/h. Nitrate adsorption decreased in the presence of sulphate, phosphate and chloride, with sulphate being the most competitive anion. The Thomas model fitted well to the fixed-bed adsorption data from four repeated adsorption/desorption cycles. Plug-flow model fitted well to the data from only the first cycle. - Highlights: • Ground coconut copra and corn cob particles surfaces are readily amine-grafted. • Amine-grafting reversed the particles' surface charge from negative to positive. • Amine-grafting of the waste particles increased nitrate adsorption capacity. • Nitrate adsorption capacity reduced by co-ions; sulphate > chloride > phosphate. • Fixed-bed nitrate adsorption data fitted well to Thomas and plug-flow models.

Enhanced removal of nitrate from water using amine-grafted agricultural wastes

International Nuclear Information System (INIS)

Kalaruban, Mahatheva; Loganathan, Paripurnanda; Shim, W.G.; Kandasamy, Jaya; Ngo, H.H.; Vigneswaran, Saravanamuthu

2016-01-01

Adsorption using low-cost adsorbents is a favourable water treatment method for the removal of water contaminants. In this study the enhanced removal of nitrate, a contaminant at elevated concentration affecting human health and causing eutrophication of water, was tested using chemically modified agricultural wastes as adsorbents. Batch and fixed-bed adsorption studies were performed on corn cob and coconut copra that were surface modified by amine-grafting to increase the surface positive charges. The Langmuir nitrate adsorption capacities (mg N/g) were 49.9 and 59.0 for the amine-grafted (AG) corn cob and coconut copra, respectively at pH 6.5 and ionic strength 1 × 10"−"3 M NaCl. These values are higher than those of many commercially available anion exchange resins. Fixed-bed (15-cm height) adsorption capacities (mg N/g) calculated from the breakthrough curves were 15.3 and 18.6 for AG corn cob and AG coconut copra, respectively, for an influent nitrate concentration 20 mg N/L at a flow velocity 5 m/h. Nitrate adsorption decreased in the presence of sulphate, phosphate and chloride, with sulphate being the most competitive anion. The Thomas model fitted well to the fixed-bed adsorption data from four repeated adsorption/desorption cycles. Plug-flow model fitted well to the data from only the first cycle. - Highlights: • Ground coconut copra and corn cob particles surfaces are readily amine-grafted. • Amine-grafting reversed the particles' surface charge from negative to positive. • Amine-grafting of the waste particles increased nitrate adsorption capacity. • Nitrate adsorption capacity reduced by co-ions; sulphate > chloride > phosphate. • Fixed-bed nitrate adsorption data fitted well to Thomas and plug-flow models.

Evaluation of zinc accumulation, allocation, and tolerance in Zea mays L. seedlings: implication for zinc phytoextraction.

Science.gov (United States)

Bashmakov, Dmitry I; Lukatkin, Alexander S; Anjum, Naser A; Ahmad, Iqbal; Pereira, Eduarda

2015-10-01

This work investigated the accumulation, allocation, and impact of zinc (Zn; 1.0 μM-10 mM) in maize (Zea mays L.) seedlings under simulated laboratory conditions. Z. mays exhibited no significant change in its habitus (the physical characteristics of plants) up to 10-1000 μM of Zn (vs 5-10 mM Zn). Zn tolerance evaluation, based on the root test, indicated a high tolerance of Z. mays to both low and intermediate (or relatively high) concentrations of Zn, whereas this plant failed to tolerate 10 mM Zn and exhibited a 5-fold decrease in its Zn tolerance. Contingent to Zn treatment levels, Zn hampered the growth of axial organs and brought decreases in the leaf area, water regime, and biomass accumulation. Nevertheless, at elevated levels of Zn (10 mM), Zn(2+) was stored in the root cytoplasm and inhibited both axial organ growth and water regime. However, accumulation and allocation of Zn in Z. mays roots, studied herein employing X-ray fluorimeter and histochemical methods, were close to Zn accumulator plants. Overall, the study outcomes revealed Zn tolerance of Z. mays, and also implicate its potential role in Zn phytoextraction.

Long-Term Safety Analysis of Baldone Radioactive Waste Repository and Updating of Waste Acceptance Criteria

International Nuclear Information System (INIS)

2001-12-01

The main objective of the project was to provide advice to the Latvian authorities on the safety enhancements and waste acceptance criteria for near surface radioactive waste disposal facilities of the Baldone repository. The project included the following main activities: Analysis of the current status of the management of radioactive waste in Latvia in general and, at the Baldone repository in particular Development of the short and long-term safety analysis of the Baldone repository, including: the planned increasing of capacity for disposal and long term storage, the radiological analysis for the post-closure period Development of the Environment Impact Statement, for the new foreseen installations, considering the non radiological components Proposal of recommendations for future updating of radioactive waste acceptance criteria Proposal of recommendations for safety upgrades to the facility. The work programme has been developed in phases and main tasks as follows. Phase 0: Project inception, Phase 1: Establishment of current status, plans and practices (Legislation, regulation and standards, Radioactive waste management, Waste acceptance criteria), Phase 2: Development of future strategies for long-term safety management and recommendations for safety enhancements. The project team found the general approach use at the installation, the basic design and the operating practices appropriate to international standards. Nevertheless, a number of items subject to potential improvements were also identified. These upgrading recommendations deal with general aspects of the management (mainly storage versus disposal of long-lived sources), site and environmental surveillance, packaging (qualification of containers, waste characterization requirements), the design of an engineered cap and strategies for capping. (author)

Preliminary study on enhancing waste management best practice model in Malaysia construction industry

Science.gov (United States)

Jamaludin, Amril Hadri; Karim, Nurulzatushima Abdul; Noor, Raja Nor Husna Raja Mohd; Othman, Nurulhidayah; Malik, Sulaiman Abdul

2017-08-01

Construction waste management (CWM) is the practice of minimizing and diverting construction waste, demolition debris, and land-clearing debris from disposal and redirecting recyclable resources back into the construction process. Best practice model means best choice from the collection of other practices that was built for purpose of construction waste management. The practice model can help the contractors in minimizing waste before the construction activities will be started. The importance of minimizing wastage will have direct impact on time, cost and quality of a construction project. This paper is focusing on the preliminary study to determine the factors of waste generation in the construction sites and identify the effectiveness of existing construction waste management practice conducted in Malaysia. The paper will also include the preliminary works of planned research location, data collection method, and analysis to be done by using the Analytical Hierarchy Process (AHP) to help in developing suitable waste management best practice model that can be used in the country.

Phytohormones enabled endophytic fungal symbiosis improve aluminum phytoextraction in tolerant Solanum lycopersicum: An examples of Penicillium janthinellum LK5 and comparison with exogenous GA3.

Science.gov (United States)

Khan, Abdul Latif; Waqas, Muhammad; Hussain, Javid; Al-Harrasi, Ahmed; Hamayun, Muhammad; Lee, In-Jung

2015-09-15

This work investigates the potentials of fungal-endophyte Penicillium janthinellum LK5 (PjLK5) and its inherent gibberellic acid (GA3) as reference to enhance aluminum (Al) induced toxicity in tolerant tomato (Solanum lycopersicum) plants. Initial screening showed significantly higher uptake of Al by PjLK5. Aluminum stress (100 μM) significantly retarted plant growth in control plants. Conversely PjLK5 and GA3 application significantly increased morphological attributes of Al-tolerant tomato plants with or without Al-stress. PjLK5 inoculation with and without Al-stress maintained the plant growth whilst extracting and translocating higher Al in shoot (∼ 1 92 mg/kg) and root (∼ 296 mg/kg). This was almost similar in GA3 treatments as well. In addition, PjLK5 inoculation extended protective effects to tomato plants by maintaining reduced cellular superoxide anions in Al stress. Al-induced oxidative stress was further reduced due to significantly higher activity of metal-responsive reduced glutathione. The functional membrane was less damaged in PjLK5 and GA3 treatments because the plants synthesized reduced levels of malondialdhyde, lenolenic and linoleic acids. Defense-related endogenous phytohormone salicylic acid was significantly up-regulated to counteract the adverse effects of Al-stress. In conclusion, the PjLK5 possess a similar bio-prospective potential as of GA3. Application of such biochemically active endophyte could increase metal phytoextraction whilst maintaining crop physiological homeostasis. Copyright © 2015 Elsevier B.V. All rights reserved.

Biological diversity of Salix taxa in Cu, Pb and Zn phytoextraction from soil.

Science.gov (United States)

Mleczek, Mirosław; Rutkowski, Paweł; Goliński, Piotr; Kaczmarek, Zygmunt; Szentner, Kinga; Waliszewska, Bogusława; Stolarski, Mariusz; Szczukowski, Stefan

2017-02-01

The aim of the study was to estimate the efficiency of copper (Cu), lead (Pb) and zinc (Zn) phytoextraction by 145 Salix taxa cultivated in an area affected by industrial activity. Survivability and biomass of plants were also analyzed. The highest Cu, Pb and Zn content in shoots was 33.38 ± 2.91 (S. purpurea × viminalis 8), 24.64 ± 1.97 (S. fragilis 1) and 58.99 ± 4.30 (S. eriocephala 7) mg kg -1 dry weight, respectively. In the case of unwashed leaves, the highest content of these metals was 135.06 ± 8.14 (S. purpurea 26), 67.98 ± 5.27 (S. purpurea 45) and 142.56 ± 12.69 (S. alba × triandra 2) mg kg -1 dw, while in washed leaves it was 106.02 ± 11.12 (S. purpurea 45), 55.06 ± 5.75 (S. purpurea 45) and 122.87 ± 12.33 (S. alba × triandra 2) mg kg -1 dw, respectively. The differences between the highest and lowest values for Cu, Pb and Zn were 545%, 20500% and 535% in shoots; 2692%, 2560% and 7500% in unwashed leaves; and 3286%, 2221% and 6950% in washed leaves, respectively. S. acutifolia was able to effectively accumulate all three metals jointly, producing shoots that were well developed in both length and diameter when compared with the other tested willows-an ability that would suggest its high suitability for practical application.

Copper phytoextraction in tandem with oilseed production using commercial cultivars and mutant lines of sunflower.

Science.gov (United States)

Kolbas, A; Mench, M; Herzig, R; Nehnevajova, E; Bes, C M

2011-01-01

Use of sunflower (Helianthus annuus L.) for Cu phytoextraction and oilseed production on Cu-contaminated topsoils was investigated in afield trial at a former wood preservation site. Six commercial cultivars and two mutant lines were cultivated in plots with and without the addition of compost (5% w/w) and dolomitic limestone (0.2% w/w). Total soil Cu ranged from 163 to 1170 mg kg(-1). In soil solutions, Cu concentration varied between 0.16-0.93 mg L(-1). The amendment increased soil pH, reduced Cu exposure and promoted sunflower growth. Stem length, shoot and capitulum biomasses, seed yield, and shoot and leaf Cu concentrations were measured. At low total soil Cu, shoot Cu mineralomass was higher in commercial cultivars, Le., Salut, Energic, and Countri, whereas competition and shading affected morphological traits of mutants. Based on shoot yield (7 Mg DW ha(-1)) and Cu concentration, the highest removal was 59 g Cu ha(-1). At high total soil Cu, shoot Cu mineralomass peaked for mutants (e.g., 52 g Cu ha(-1) for Mutant 1 line) and cultivars Energic and Countri. Energic seed yield (3.9 Mg air-DW ha(-1)) would be sufficient to produce oil Phenotype traits and shoot Cu removal depended on sunflower types and Cu exposure.

Enhanced hydrolysis and methane yield by applying microaeration pretreatment to the anaerobic co-digestion of brown water and food waste

International Nuclear Information System (INIS)

Lim, Jun Wei; Wang, Jing-Yuan

2013-01-01

Highlights: ► Microaeration pretreatment was effective for brown water and food waste mixture. ► The added oxygen was consumed fully by facultative microorganisms. ► Enhanced solubilization, acidification and breakdown of SCFAs to acetate. ► Microaeration pretreatment improved methane yield by 10–21%. ► Nature of inoculum influenced the effects of microaeration. - Abstract: Microaeration has been used conventionally for the desulphurization of biogas, and recently it was shown to be an alternative pretreatment to enhance hydrolysis of the anaerobic digestion (AD) process. Previous studies on microaeration pretreatment were limited to the study of substrates with complex organic matter, while little has been reported on its effect on substrates with higher biodegradability such as brown water and food waste. Due to the lack of consistent microaeration intensities, previous studies were not comparable and thus inconclusive in proving the effectiveness of microaeration to the overall AD process. In this study, the role of microaeration pretreatment in the anaerobic co-digestion of brown water and food waste was evaluated in batch-tests. After a 4-day pretreatment with 37.5 mL-O 2 /L R -d added to the liquid phase of the reactor, the methane production of substrates were monitored in anaerobic conditions over the next 40 days. The added oxygen was consumed fully by facultative microorganisms and a reducing environment for organic matter degradation was maintained. Other than higher COD solubilization, microaeration pretreatment led to greater VFA accumulation and the conversion of other short chain fatty acids to acetate. This could be due to enhanced activities of hydrolytic and acidogenic bacteria and the degradation of slowly biodegradable compounds under microaerobic conditions. This study also found that the nature of inoculum influenced the effects of microaeration as a 21% and 10% increase in methane yield was observed when pretreatment was applied

Enhanced hydrolysis and methane yield by applying microaeration pretreatment to the anaerobic co-digestion of brown water and food waste

Energy Technology Data Exchange (ETDEWEB)

Lim, Jun Wei [Residues and Resource Reclamation Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 06-08 CleanTech One, 1 Cleantech Loop, Singapore 637141 (Singapore); School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Wang, Jing-Yuan, E-mail: jywang@ntu.edu.sg [Residues and Resource Reclamation Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 06-08 CleanTech One, 1 Cleantech Loop, Singapore 637141 (Singapore); School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

2013-04-15

Highlights: ► Microaeration pretreatment was effective for brown water and food waste mixture. ► The added oxygen was consumed fully by facultative microorganisms. ► Enhanced solubilization, acidification and breakdown of SCFAs to acetate. ► Microaeration pretreatment improved methane yield by 10–21%. ► Nature of inoculum influenced the effects of microaeration. - Abstract: Microaeration has been used conventionally for the desulphurization of biogas, and recently it was shown to be an alternative pretreatment to enhance hydrolysis of the anaerobic digestion (AD) process. Previous studies on microaeration pretreatment were limited to the study of substrates with complex organic matter, while little has been reported on its effect on substrates with higher biodegradability such as brown water and food waste. Due to the lack of consistent microaeration intensities, previous studies were not comparable and thus inconclusive in proving the effectiveness of microaeration to the overall AD process. In this study, the role of microaeration pretreatment in the anaerobic co-digestion of brown water and food waste was evaluated in batch-tests. After a 4-day pretreatment with 37.5 mL-O{sub 2}/L{sub R}-d added to the liquid phase of the reactor, the methane production of substrates were monitored in anaerobic conditions over the next 40 days. The added oxygen was consumed fully by facultative microorganisms and a reducing environment for organic matter degradation was maintained. Other than higher COD solubilization, microaeration pretreatment led to greater VFA accumulation and the conversion of other short chain fatty acids to acetate. This could be due to enhanced activities of hydrolytic and acidogenic bacteria and the degradation of slowly biodegradable compounds under microaerobic conditions. This study also found that the nature of inoculum influenced the effects of microaeration as a 21% and 10% increase in methane yield was observed when pretreatment was

Waste transmutation and public acceptance

International Nuclear Information System (INIS)

Pigford, T.H.

1991-01-01

The concept of transmuting radioactive wastes with reactors or accelerators is appealing. It has the potential of simplifying or eliminating problems of disposing of nuclear waste. The transmutation concept has been renewed vigorously at a time when national projects to dispose of high-level and transuranic waste are seriously delayed. In this period of tightening federal funds and program curtailments, skilled technical staffs are available at US Department of Energy (DOE) national laboratories and contractors to work on waste transmutation. If the claims of transmutation can be shown to be realistic, economically feasible, and capable of being implemented within the US institutional infrastructure, public acceptance of nuclear waste disposal may be enhanced. If the claims for transmutation are not substantiated, however, there will result a serious loss of credibility and an unjust exacerbation of public concerns about nuclear waste. The paper discusses the following topics: how public acceptance is achieved; the technical community and waste disposal; transmutation and technical communication; transmutation issues; technical fixes and public perception

Remediation of toxic ad hazardous wastes: plants as biological agents to mitigate heavy metal pollution

International Nuclear Information System (INIS)

Cadiz, Nina M.; Principe, Eduardo B.

2005-01-01

This papers introduced the plants as biological agents to control heavy metal pollution and the process used the green plants to clean contaminated soils or to render the toxic ions harmless is a new technology called phytoremediation with two levels, the phytostabilization and phytoextraction

Remote automated material handling of radioactive waste containers

International Nuclear Information System (INIS)

Greager, T.M.

1994-09-01

To enhance personnel safety, improve productivity, and reduce costs, the design team incorporated a remote, automated stacker/retriever, automatic inspection, and automated guidance vehicle for material handling at the Enhanced Radioactive and Mixed Waste Storage Facility - Phase V (Phase V Storage Facility) on the Hanford Site in south-central Washington State. The Phase V Storage Facility, scheduled to begin operation in mid-1997, is the first low-cost facility of its kind to use this technology for handling drums. Since 1970, the Hanford Site's suspect transuranic (TRU) wastes and, more recently, mixed wastes (both low-level and TRU) have been accumulating in storage awaiting treatment and disposal. Currently, the Hanford Site is only capable of onsite disposal of radioactive low-level waste (LLW). Nonradioactive hazardous wastes must be shipped off site for treatment. The Waste Receiving and Processing (WRAP) facilities will provide the primary treatment capability for solid-waste storage at the Hanford Site. The Phase V Storage Facility, which accommodates 27,000 drum equivalents of contact-handled waste, will provide the following critical functions for the efficient operation of the WRAP facilities: (1) Shipping/Receiving; (2) Head Space Gas Sampling; (3) Inventory Control; (4) Storage; (5) Automated/Manual Material Handling

ENHANCED DOE HIGH LEVEL WASTE MELTER THROUGHPUT STUDIES: SRNL GLASS SELECTION STRATEGY

Energy Technology Data Exchange (ETDEWEB)

Raszewski, F; Tommy Edwards, T; David Peeler, D

2008-01-23

The Department of Energy has authorized a team of glass formulation and processing experts at the Savannah River National Laboratory (SRNL), the Pacific Northwest National Laboratory (PNNL), and the Vitreous State Laboratory (VSL) at Catholic University of America to develop a systematic approach to increase high level waste melter throughput (by increasing waste loading with minimal or positive impacts on melt rate). This task is aimed at proof-of-principle testing and the development of tools to improve waste loading and melt rate, which will lead to higher waste throughput. Four specific tasks have been proposed to meet these objectives (for details, see WSRC-STI-2007-00483): (1) Integration and Oversight, (2) Crystal Accumulation Modeling (led by PNNL)/Higher Waste Loading Glasses (led by SRNL), (3) Melt Rate Evaluation and Modeling, and (4) Melter Scale Demonstrations. Task 2, Crystal Accumulation Modeling/Higher Waste Loading Glasses is the focus of this report. The objective of this study is to provide supplemental data to support the possible use of alternative melter technologies and/or implementation of alternative process control models or strategies to target higher waste loadings (WLs) for the Defense Waste Processing Facility (DWPF)--ultimately leading to higher waste throughputs and a reduced mission life. The glass selection strategy discussed in this report was developed to gain insight into specific technical issues that could limit or compromise the ability of glass formulation efforts to target higher WLs for future sludge batches at the Savannah River Site (SRS). These technical issues include Al-dissolution, higher TiO{sub 2} limits and homogeneity issues for coupled-operations, Al{sub 2}O{sub 3} solubility, and nepheline formation. To address these technical issues, a test matrix of 28 glass compositions has been developed based on 5 different sludge projections for future processing. The glasses will be fabricated and characterized based on

100-N Area Strontium-90 Treatability Demonstration Project: Phytoextraction Along the 100-N Columbia River Riparian Zone – Field Treatability Study

Energy Technology Data Exchange (ETDEWEB)

Fellows, Robert J.; Fruchter, Jonathan S.; Driver, Crystal J.; Ainsworth, Calvin C.

2010-01-11

Strontium-90 (90Sr) is present both in the aquifer near the river and in the vadose and riparian zones of the river’s shore at 100-NR-2. Phytoextraction of 90Sr is being considered as a potential remediation system along the riparian zone of the Columbia River. Phytoextraction would employ coyote willow (Salix exigua). Past studies have shown that willow roots share uptake mechanisms for Sr with Ca, a plant macronutrient as well as no discrimination between Sr and 90Sr. Willow 90Sr concentration ratios [CR’s; (pCi 90Sr/g dry wt. of new growth tissue)/(pCi 90Sr/g soil porewater)] were consistently greater than 65 with three-quarters of the assimilated label partitioned into the above ground shoot. Insect herbivore experiments also demonstrated no significant potential for bioaccumulation or food chain transfer from their natural activities. The objectives of this field study were three-fold: (1) to demonstrate that a viable, “managed” plot of coyote willows can be established on the shoreline of the Columbia River that would survive the same microenvironment to be encountered at the 100-NR-2 shoreline; (2) to show through engineered barriers that large and small animal herbivores can be prevented from feeding on these plants; and (3) to show that once established, the plants will provide sufficient biomass annually to support the phytoextraction technology. A field treatability demonstration plot was established on the Columbia River shoreline alongside the 100-K West water intake at the end of January 2007. The plot was delimited by a 3.05 m high chain-link fence and was approximately 10 x 25 m in size. A layer of fine mesh metal small animal screening was placed around the plot at the base of the fencing to a depth of 45 cm. A total of sixty plants were placed in six slightly staggered rows with 1-m spacing between plants. The actual plot size was 0.00461 hectare (ha). At the time of planting (March 12, 2007), the plot was located about 10 m from the

Waste-to-energy: Dehalogenation of plastic-containing wastes.

Science.gov (United States)

Shen, Yafei; Zhao, Rong; Wang, Junfeng; Chen, Xingming; Ge, Xinlei; Chen, Mindong

2016-03-01

The dehalogenation measurements could be carried out with the decomposition of plastic wastes simultaneously or successively. This paper reviewed the progresses in dehalogenation followed by thermochemical conversion of plastic-containing wastes for clean energy production. The pre-treatment method of MCT or HTT can eliminate the halogen in plastic wastes. The additives such as alkali-based metal oxides (e.g., CaO, NaOH), iron powders and minerals (e.g., quartz) can work as reaction mediums and accelerators with the objective of enhancing the mechanochemical reaction. The dehalogenation of waste plastics could be achieved by co-grinding with sustainable additives such as bio-wastes (e.g., rice husk), recyclable minerals (e.g., red mud) via MCT for solid fuels production. Interestingly, the solid fuel properties (e.g., particle size) could be significantly improved by HTT in addition with lignocellulosic biomass. Furthermore, the halogenated compounds in downstream thermal process could be eliminated by using catalysts and adsorbents. Most dehalogenation of plastic wastes primarily focuses on the transformation of organic halogen into inorganic halogen in terms of halogen hydrides or salts. The integrated process of MCT or HTT with the catalytic thermal decomposition is a promising way for clean energy production. The low-cost additives (e.g., red mud) used in the pre-treatment by MCT or HTT lead to a considerable synergistic effects including catalytic effect contributing to the follow-up thermal decomposition. Copyright © 2015 Elsevier Ltd. All rights reserved.

An LCA model for waste incineration enhanced with new technologies for metal recovery and application to the case of Switzerland

Energy Technology Data Exchange (ETDEWEB)

Boesch, Michael E. [Aveny GmbH, Schwandenholzstr. 212, CH-8046 Zürich (Switzerland); Vadenbo, Carl, E-mail: vadenbo@ifu.baug.ethz.ch [ETH Zurich, Institute of Environmental Engineering, Schafmattstrasse 6, CH-8093 Zurich (Switzerland); Saner, Dominik [Swiss Post, Communications, Politics and Social Responsibility, Viktoriastrasse 21, P.O. Box, CH-3030 Berne (Switzerland); Huter, Christoph [City of Zürich, ERZ Entsorgung - Recycling Zürich, Hagenholzstrasse 110, P.O. Box, CH-8050 Zürich (Switzerland); Hellweg, Stefanie [ETH Zurich, Institute of Environmental Engineering, Schafmattstrasse 6, CH-8093 Zurich (Switzerland)

2014-02-15

Highlights: • An enhanced process-based LCA model for MSWI is featured and applied in case study. • LCA modeling of recent technological developments for metal recovery from fly ash. • Net release from Swiss MSWI 133 kg CO{sub 2}-eq/tonne waste from attributional LCA perspective. • Net savings from a consequential LCA perspective reach up to 303 kg CO{sub 2}-eq/tonne waste. • Impacts according to ReCiPe and CExD show similar pattern to climate change. - Abstract: A process model of municipal solid waste incinerators (MSWIs) and new technologies for metal recovery from combustion residues was developed. The environmental impact is modeled as a function of waste composition as well as waste treatment and material recovery technologies. The model includes combustion with a grate incinerator, several flue gas treatment technologies, electricity and steam production from waste heat recovery, metal recovery from slag and fly ash, and landfilling of residues and can be tailored to specific plants and sites (software tools can be downloaded free of charge). Application of the model to Switzerland shows that the treatment of one tonne of municipal solid waste results on average in 425 kg CO{sub 2}-eq. generated in the incineration process, and 54 kg CO{sub 2}-eq. accrue in upstream processes such as waste transport and the production of operating materials. Downstream processes, i.e. residue disposal, generates 5 kg CO{sub 2}-eq. Savings from energy recovery are in the range of 67 to 752 kg CO{sub 2}-eq. depending on the assumptions regarding the substituted energy production, while the recovery of metals from slag and fly ash currently results in a net saving of approximately 35 kg CO{sub 2}-eq. A similar impact pattern is observed when assessing the MSWI model for aggregated environmental impacts (ReCiPe) and for non-renewable resource consumption (cumulative exergy demand), except that direct emissions have less and no relevance, respectively, on the total

An LCA model for waste incineration enhanced with new technologies for metal recovery and application to the case of Switzerland

International Nuclear Information System (INIS)

Boesch, Michael E.; Vadenbo, Carl; Saner, Dominik; Huter, Christoph; Hellweg, Stefanie

2014-01-01

Highlights: • An enhanced process-based LCA model for MSWI is featured and applied in case study. • LCA modeling of recent technological developments for metal recovery from fly ash. • Net release from Swiss MSWI 133 kg CO 2 -eq/tonne waste from attributional LCA perspective. • Net savings from a consequential LCA perspective reach up to 303 kg CO 2 -eq/tonne waste. • Impacts according to ReCiPe and CExD show similar pattern to climate change. - Abstract: A process model of municipal solid waste incinerators (MSWIs) and new technologies for metal recovery from combustion residues was developed. The environmental impact is modeled as a function of waste composition as well as waste treatment and material recovery technologies. The model includes combustion with a grate incinerator, several flue gas treatment technologies, electricity and steam production from waste heat recovery, metal recovery from slag and fly ash, and landfilling of residues and can be tailored to specific plants and sites (software tools can be downloaded free of charge). Application of the model to Switzerland shows that the treatment of one tonne of municipal solid waste results on average in 425 kg CO 2 -eq. generated in the incineration process, and 54 kg CO 2 -eq. accrue in upstream processes such as waste transport and the production of operating materials. Downstream processes, i.e. residue disposal, generates 5 kg CO 2 -eq. Savings from energy recovery are in the range of 67 to 752 kg CO 2 -eq. depending on the assumptions regarding the substituted energy production, while the recovery of metals from slag and fly ash currently results in a net saving of approximately 35 kg CO 2 -eq. A similar impact pattern is observed when assessing the MSWI model for aggregated environmental impacts (ReCiPe) and for non-renewable resource consumption (cumulative exergy demand), except that direct emissions have less and no relevance, respectively, on the total score. The study illustrates

Biological considerations in nuclear decommissioning, and radioactive waste management

International Nuclear Information System (INIS)

Rees, J.F.

1991-01-01

The importance of natural processes such as microbial action in waste management has recently been recognised. Although it is often difficult to predict the effects because the interactive processes are complex, human intervention can optimize the process. This paper highlights some of the fundamental stages in the management of low- and intermediate-level radioactive wastes where particular uncertainties exist and which might benefit from controlled microbial intervention. The areas considered are the use of biodegradable surfactants for cleaning surfaces before disposal, microbial adsorption and concentration of intermediate-level wastes from solution, microbial transformation of intermediate-level wastes organic fractions, enhancement of radionuclide transfer to the atmosphere, enhancement of transfer into vadose zone and ground water and the microbial treatment of any oily residues. (UK)

Alternative disposal options for transuranic waste

International Nuclear Information System (INIS)

Loomis, G.G.

1994-01-01

Three alternative concepts are proposed for the final disposal of stored and retrieved buried transuranic waste. These proposed options answer criticisms of the existing U.S. Department of Energy strategy of directly disposing of stored transuranic waste in deep, geological salt formations at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, New Mexico. The first option involves enhanced stabilization of stored waste by thermal treatment followed by convoy transportation and internment in the existing WIPP facility. This concept could also be extended to retrieved buried waste with proper permitting. The second option involves in-state, in situ internment using an encapsulating lens around the waste. This concept applies only to previously buried transuranic waste. The third option involves sending stored and retrieved waste to the Nevada Test Site and configuring the waste around a thermonuclear device from the U.S. or Russian arsenal in a specially designed underground chamber. The thermonuclear explosion would transmute plutonium and disassociate hazardous materials while entombing the waste in a national sacrifice area

Melter Throughput Enhancements for High-Iron HLW

Energy Technology Data Exchange (ETDEWEB)

Kruger, A. A. [Department of Energy, Office of River Protection, Richland, Washington (United States); Gan, Hoa [The Catholic University of America, Washington, DC (United States); Joseph, Innocent [The Catholic University of America, Washington, DC (United States); Pegg, Ian L. [The Catholic University of America, Washington, DC (United States); Matlack, Keith S. [The Catholic University of America, Washington, DC (United States); Chaudhuri, Malabika [The Catholic University of America, Washington, DC (United States); Kot, Wing [The Catholic University of America, Washington, DC (United States)

2012-12-26

This report describes work performed to develop and test new glass and feed formulations in order to increase glass melting rates in high waste loading glass formulations for HLW with high concentrations of iron. Testing was designed to identify glass and melter feed formulations that optimize waste loading and waste processing rate while meeting all processing and product quality requirements. The work included preparation and characterization of crucible melts to assess melt rate using a vertical gradient furnace system and to develop new formulations with enhanced melt rate. Testing evaluated the effects of waste loading on glass properties and the maximum waste loading that can be achieved. The results from crucible-scale testing supported subsequent DuraMelter 100 (DM100) tests designed to examine the effects of enhanced glass and feed formulations on waste processing rate and product quality. The DM100 was selected as the platform for these tests due to its extensive previous use in processing rate determination for various HLW streams and glass compositions.

Enhanced phytoremediation potential of polychlorinated biphenyl contaminated soil from e-waste recycling area in the presence of randomly methylated-β-cyclodextrins

International Nuclear Information System (INIS)

Shen Chaofeng; Tang Xianjin; Cheema, Sardar Alam; Zhang Congkai; Khan, Muhammad Imran; Liang Fang; Chen Xincai; Zhu Youfeng; Lin Qi; Chen, Yingxu

2009-01-01

The crude recycling of electronic and electric waste (e-waste) is now creating soil pollution problems with organic compounds such as polychlorinated biphenyls (PCBs). The present study aimed to compare the phytoremediation potential of four plant species (rice, alfalfa, ryegrass and tall fescue) for PCBs contaminated soil from Taizhou city, one of the largest e-waste recycling centers in China. In addition, the enhanced effects of randomly methylated-β-cyclodextrins (RAMEB) on PCBs phytoremediation potential were evaluated. Higher PCBs removal percentages of 25.6-28.5% in rhizosphere soil were observed after 120 days, compared with those of the non-rhizosphere (10.4-16.9%) and unplanted controls (7.3%). The average PCBs removal percentages of four plant species increased from 26.9% to 37.1% in the rhizosphere soil with addition of RAMEB. Meanwhile, relatively high microbial counts and dehydrogenase activity were detected in planted soils and a stimulatory effect by RAMEB addition was found. The present study indicated that all the plant candidates were feasible for phytoremediation of PCBs contaminated soil from the e-waste recycling area, and tall fescue with RAMEB amendment seemed as a promising remediation strategy. High PCBs removal percentage was due to the increased PCBs bioavailability as well as biostimulation of microbial communities after plantation and RAMEB addition.

Enhanced phytoremediation potential of polychlorinated biphenyl contaminated soil from e-waste recycling area in the presence of randomly methylated-{beta}-cyclodextrins

Energy Technology Data Exchange (ETDEWEB)

Shen Chaofeng [Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029 (China); MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Hangzhou 310029 (China); Tang Xianjin; Cheema, Sardar Alam; Zhang Congkai; Khan, Muhammad Imran; Liang Fang; Chen Xincai; Zhu Youfeng [Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029 (China); Lin Qi, E-mail: linqi@zju.edu.cn [Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029 (China); Chen, Yingxu [Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029 (China)

2009-12-30

The crude recycling of electronic and electric waste (e-waste) is now creating soil pollution problems with organic compounds such as polychlorinated biphenyls (PCBs). The present study aimed to compare the phytoremediation potential of four plant species (rice, alfalfa, ryegrass and tall fescue) for PCBs contaminated soil from Taizhou city, one of the largest e-waste recycling centers in China. In addition, the enhanced effects of randomly methylated-{beta}-cyclodextrins (RAMEB) on PCBs phytoremediation potential were evaluated. Higher PCBs removal percentages of 25.6-28.5% in rhizosphere soil were observed after 120 days, compared with those of the non-rhizosphere (10.4-16.9%) and unplanted controls (7.3%). The average PCBs removal percentages of four plant species increased from 26.9% to 37.1% in the rhizosphere soil with addition of RAMEB. Meanwhile, relatively high microbial counts and dehydrogenase activity were detected in planted soils and a stimulatory effect by RAMEB addition was found. The present study indicated that all the plant candidates were feasible for phytoremediation of PCBs contaminated soil from the e-waste recycling area, and tall fescue with RAMEB amendment seemed as a promising remediation strategy. High PCBs removal percentage was due to the increased PCBs bioavailability as well as biostimulation of microbial communities after plantation and RAMEB addition.

Thermal conductivity of multibarrier waste form components

International Nuclear Information System (INIS)

Lokken, R.O.

1981-01-01

The multiple barrier concept of radioactive waste immobilization under investigation at Pacific Northwest Laboratory (PNL) uses composite waste forms which exhibit enhanced inertness through improvements in thermal stability, mechanical strength, and leachability by the use of coatings and metal matrices. Since excessive heat may be generated by radioactive decay of the waste, the thermal conductivity of the various barriers, and more importantly of the composite, becomes an important parameter in design criteria. This report presents results of thermal conductivity measurements on 21 various glass, ceramic, metal and composite materials used in multibarrier waste forms development

Two-step sequential pretreatment for the enhanced enzymatic hydrolysis of coffee spent waste.

Science.gov (United States)

Ravindran, Rajeev; Jaiswal, Swarna; Abu-Ghannam, Nissreen; Jaiswal, Amit K

2017-09-01

In the present study, eight different pretreatments of varying nature (physical, chemical and physico-chemical) followed by a sequential, combinatorial pretreatment strategy was applied to spent coffee waste to attain maximum sugar yield. Pretreated samples were analysed for total reducing sugar, individual sugars and generation of inhibitory compounds such as furfural and hydroxymethyl furfural (HMF) which can hinder microbial growth and enzyme activity. Native spent coffee waste was high in hemicellulose content. Galactose was found to be the predominant sugar in spent coffee waste. Results showed that sequential pretreatment yielded 350.12mg of reducing sugar/g of substrate, which was 1.7-fold higher than in native spent coffee waste (203.4mg/g of substrate). Furthermore, extensive delignification was achieved using sequential pretreatment strategy. XRD, FTIR, and DSC profiles of the pretreated substrates were studied to analyse the various changes incurred in sequentially pretreated spent coffee waste as opposed to native spent coffee waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

Plastic solidification method for radioactive waste

International Nuclear Information System (INIS)

Tomita, Toshihide; Inakuma, Masahiko.

1992-01-01

Condensed liquid wastes in radioactive wastes are formed by mixing and condensing several kinds of liquid wastes such as liquid wastes upon regeneration of ion exchange resins, floor draining liquid wastes and equipment draining liquid wastes. Accordingly, various materials are contained, and it is found that polymerization reaction of plastics is inhibited especially when reductive material, such as sodium nitrite is present. Then, in the present invention, upon mixing thermosetting resins to radioactive wastes containing reducing materials, an alkaline material is admixed to an unstaturated polyester resin. This can inactivate the terminal groups of unsaturated polyester chain, to prevent the dissociation of the reducing agent such as sodium nitrite. Further, if an unsaturated polyester resin of low acid value and a polymerization initiator for high temperature are used in addition to the alkaline material, the effect is further enhanced, thereby enabling to obtain a strong plastic solidification products. (T.M.)

Enhanced volatile fatty acids production from anaerobic fermentation of food waste: A mini-review focusing on acidogenic metabolic pathways.

Science.gov (United States)

Zhou, Miaomiao; Yan, Binghua; Wong, Jonathan W C; Zhang, Yang

2018-01-01

Recently, efficient disposal of food waste (FW) with potential resource recovery has attracted great attentions. Due to its easily biodegradable nature, rich nutrient availability and high moisture content, FW is regarded as favorable substrate for anaerobic digestion (AD). Both waste disposal and energy recovery can be fulfilled during AD of FW. Volatile fatty acids (VFAs) which are the products of the first-two stages of AD, are widely applied in chemical industry as platform chemicals recently. Concentration and distribution of VFAs is the result of acidogenic metabolic pathways, which can be affected by the micro-environment (e.g. pH) in the digester. Hence, the clear elucidation of the acidogenic metabolic pathways is essential for optimization of acidogenic process for efficient product recovery. This review summarizes major acidogenic metabolic pathways and regulating strategies for enhancing VFAs recovery during acidogenic fermentation of FW. Copyright © 2017 Elsevier Ltd. All rights reserved.

FY 2001 Hanford Waste Management Strategic Plan

International Nuclear Information System (INIS)

COLLINS, M.S.

2001-01-01

We are pleased to present the 2001 Hanford Waste Management Program Strategic Plan. This plan supports the newly developed U. S. Department of Energy Site outcomes strategy. The 2001 Plan reflects current and projected needs for Waste Management Program services in support of Hanford Site cleanup, and updates the objectives and actions using new waste stream oriented logic for the strategic goals: (1) waste treatment/processing, storage, and disposal; (2) interfaces; and (3) program excellence. Overall direction for the Program is provided by the Waste Management Division, Office of the Assistant Manager for Environmental Restoration and Waste Management, U. S. Department of Energy, Richland Operations Office. Fluor Hanford, Inc. is the operating contractor for the program. This Plan documents proactive strategies for planning and budgeting, with a major focus on helping meet regulatory commitments in a timely and efficient manner and concurrently assisting us in completing programs cheaper, better and quicker. Newly developed waste stream oriented logic was incorporated to clarify Site outcomes. External drivers, technology inputs, treatment/processing, storage and disposal strategies, and stream specific strategies are included for the six major waste types addressed in this Plan (low-level waste, mixed low-level waste, contact-handled transuranic waste, remote-handled transuranic waste, liquid waste, and cesium/strontium capsules). The key elements of the strategy are identification and quantification of the needs for waste management services, assessment of capabilities, and development of cost-effective actions to meet the needs and to continuously improve performance. Accomplishment of specific actions as set forth in the Plan depends on continued availability of the required resources and funding. The primary objectives of Plan are: (1) enhance the Waste Management Program to improve flexibility, become more holistic especially by implementing new

What to do with radioactive wastes?

International Nuclear Information System (INIS)

2006-01-01

This power point presentation (82 slides) gives information on what is a radioactive waste, radioactivity and historical review of radioactivity, radioactive period, natural radioactivity (with examples of data), the three main radiation types (α, β, γ), the origin of radioactive wastes (nuclear power, research, defense, other), the proportion of radioactive wastes in the total of industrial wastes in France, the classification of nuclear wastes according to their activity and period, the quantities and their storage means, the 1991 december 30 law (France) related to the radioactive waste management, the situation in other countries (Germany, Belgium, Canada, USA, Finland, Japan, Netherlands, Sweden, Switzerland), volume figures and previsions for the various waste types in 2004, 2010 and 2020, the storage perspectives, the French national debate on radioactive waste management and the objective of perpetuated solutions, the enhancement of the public information, the 15 June 2006 law on a sustainable management of radioactive materials and wastes with three main axis (deep separation and transmutation, deep storage, waste conditioning and long term surface storage), and the development of a nuclear safety and waste culture that could be extended to other types of industry

TESTING OF ENHANCED CHEMICAL CLEANING OF SRS ACTUAL WASTE TANK 5F AND TANK 12H SLUDGES

Energy Technology Data Exchange (ETDEWEB)

Martino, C.; King, W.

2011-08-22

Forty three of the High Level Waste (HLW) tanks at the Savannah River Site (SRS) have internal structures that hinder removal of the last approximately five thousand gallons of waste sludge solely by mechanical means. Chemical cleaning can be utilized to dissolve the sludge heel with oxalic acid (OA) and pump the material to a separate waste tank in preparation for final disposition. This dissolved sludge material is pH adjusted downstream of the dissolution process, precipitating the sludge components along with sodium oxalate solids. The large quantities of sodium oxalate and other metal oxalates formed impact downstream processes by requiring additional washing during sludge batch preparation and increase the amount of material that must be processed in the tank farm evaporator systems and the Saltstone Processing Facility. Enhanced Chemical Cleaning (ECC) was identified as a potential method for greatly reducing the impact of oxalate additions to the SRS Tank Farms without adding additional components to the waste that would extend processing or increase waste form volumes. In support of Savannah River Site (SRS) tank closure efforts, the Savannah River National Laboratory (SRNL) conducted Real Waste Testing (RWT) to evaluate an alternative to the baseline 8 wt. % OA chemical cleaning technology for tank sludge heel removal. The baseline OA technology results in the addition of significant volumes of oxalate salts to the SRS tank farm and there is insufficient space to accommodate the neutralized streams resulting from the treatment of the multiple remaining waste tanks requiring closure. ECC is a promising alternative to bulk OA cleaning, which utilizes a more dilute OA (nominally 2 wt. % at a pH of around 2) and an oxalate destruction technology. The technology is being adapted by AREVA from their decontamination technology for Nuclear Power Plant secondary side scale removal. This report contains results from the SRNL small scale testing of the ECC process

Appliance of geochemical engineering in radioactive waste disposal

International Nuclear Information System (INIS)

Li Shuang; Zhang Chengjiang; Ni Shijun; Li Kuanliang

2008-01-01

The basic foundation of applying geochemical engineering to control environment, common engineering models of disposal radioactive waste and the functions of the engineering barriers are introduced in this paper. The authors take the geochemical engineering barrier materiel research of a radioactive waste repository as an example to explain the appliance of geochemical engineering in the disposal of radioactive waste. And the results show that it can enhance the security of the nuclear waste repository if we use geochemical engineering barrier. (authors)

Enhanced waste activated sludge digestion using a submerged anaerobic dynamic membrane bioreactor: performance, sludge characteristics and microbial community

Science.gov (United States)

Yu, Hongguang; Wang, Zhiwei; Wu, Zhichao; Zhu, Chaowei

2016-02-01

Anaerobic digestion (AD) plays an important role in waste activated sludge (WAS) treatment; however, conventional AD (CAD) process needs substantial improvements, especially for the treatment of WAS with low solids content and poor anaerobic biodegradability. Herein, we propose a submerged anaerobic dynamic membrane bioreactor (AnDMBR) for simultaneous WAS thickening and digestion without any pretreatment. During the long-term operation, the AnDMBR exhibited an enhanced sludge reduction and improved methane production over CAD process. Moreover, the biogas generated in the AnDMBR contained higher methane content than CAD process. Stable carbon isotopic signatures elucidated the occurrence of combined methanogenic pathways in the AnDMBR process, in which hydrogenotrophic methanogenic pathway made a larger contribution to the total methane production. It was also found that organic matter degradation was enhanced in the AnDMBR, thus providing more favorable substrates for microorganisms. Pyrosequencing revealed that Proteobacteria and Bacteroidetes were abundant in bacterial communities and Methanosarcina and Methanosaeta in archaeal communities, which played an important role in the AnDMBR system. This study shed light on the enhanced digestion of WAS using AnDMBR technology.

Microbial Insight into a Pilot-Scale Enhanced Two-Stage High-Solid Anaerobic Digestion System Treating Waste Activated Sludge.

Science.gov (United States)

Wu, Jing; Cao, Zhiping; Hu, Yuying; Wang, Xiaolu; Wang, Guangqi; Zuo, Jiane; Wang, Kaijun; Qian, Yi

2017-11-30

High solid anaerobic digestion (HSAD) is a rapidly developed anaerobic digestion technique for treating municipal sludge, and has been widely used in Europe and Asia. Recently, the enhanced HSAD process with thermal treatment showed its advantages in both methane production and VS reduction. However, the understanding of the microbial community is still poor. This study investigated microbial communities in a pilot enhanced two-stage HSAD system that degraded waste activated sludge at 9% solid content. The system employed process "thermal pre-treatment (TPT) at 70 °C, thermophilic anaerobic digestion (TAD), and mesophilic anaerobic digestion (MAD)". Hydrogenotrophic methanogens Methanothermobacter spp. dominated the system with relative abundance up to about 100% in both TAD and MAD. Syntrophic acetate oxidation (SAO) bacteria were discovered in TAD, and they converted acetate into H₂ and CO₂ to support hydrogenotrophic methanogenesis. The microbial composition and conversion route of this system are derived from the high solid content and protein content in raw sludge, as well as the operational conditions. This study could facilitate the understanding of the enhanced HSAD process, and is of academic and industrial importance.

Distribution of P, K, Ca, Mg, Cd, Cu, Fe, Mn, Pb and Zn in wood and bark age classes of willows and poplars used for phytoextraction on soils contaminated by risk elements.

Science.gov (United States)

Zárubová, Pavla; Hejcman, Michal; Vondráčková, Stanislava; Mrnka, Libor; Száková, Jiřina; Tlustoš, Pavel

2015-12-01

Fast-growing clones of Salix and Populus have been studied for remediation of soils contaminated by risk elements (RE) using short-rotation coppice plantations. Our aim was to assess biomass yield and distributions of elements in wood and bark of highly productive willow (S1--[Salix schwerinii × Salix viminalis] × S. viminalis, S2--Salix × smithiana clone S-218) and poplar (P1--Populus maximowiczii × Populus nigra, P2--P. nigra) clones with respect to aging. The field experiment was established in April 2008 on moderately Cd-, Pb- and Zn- contaminated soil. Shoots were harvested after four seasons (February 2012) and separated into annual classes of wood and bark. All tested clones grew on contaminated soils, with highest biomass production and lowest mortality exhibited by P1 and S2. Concentrations of elements, with exception of Ca and Pb, decreased with age and were higher in bark than in wood. The Salix clones were characterised by higher removal of Cd, Mn and Zn compared to the Populus clones. Despite generally higher RE content in young shoots, partly due to lower wood/bark ratios and higher RE concentrations in bark, the overall removal of RE was higher in older wood classes due to higher biomass yield. Thus, longer rotations seem to be more effective when phytoextraction strategy is considered. Of the four selected clones, S1 exhibited the best removal of Cd and Zn and is a good candidate for phytoextraction.

Phytoextraction and estimating optimal time for remediation of Cd-contaminated soils by Spinach

Directory of Open Access Journals (Sweden)

Somayyeh Eisazadeh Lazarjan

2016-05-01

Full Text Available The so-called phytoextraction in which hyperaccumulator plants are used to remediate the contaminated soils is proven to be an efficient method. The objective of this study was to investigate the capability of Spinach for phytoremediation of cadmium from Cd-contaminated soils and determine the efficiency extent of spinach for phytoremediation. For this purpose, a randomized block experimental design whit five treatments including 0, 15, 30, 60 and 120 mg Cd/ kg soil and three replications was established in the greenhouse. After contamination the soils with different levels of cadmium, spinach seeds were planted. When plants were fully developed, plants were harvested and their cadmium contents in shoot and roots as well as the soil-cadmium were measured. The results indicated that by increasing Cd concentration in soil, the major Cd accumulation was occurred in the roots rather than shoots. Maximum cadmium concentration within the shoots and roots was 73.7 and 75.86 mg/kg soil, respectively. According to Spinach ability to absorb high concentration of cadmium in the root zone and its high biomass and capability of Cadmium accumulation in shoots, Spinach can be used as hyperaccumulator plant to remediate cadmium from Cd-contaminated soils. But, according to minimum remediation time and maximum dry matter for the 30 mg Cd/ kg soil, maximum Cd extracted by shoots in hectare/year was in 30 mg Cd/ kg soil. It can be concluded that Spinach is a suitable plant for phytoremediation of slightly and to moderately cadmium contaminated soils.

Factors influencing chemical durability of nuclear waste glasses

International Nuclear Information System (INIS)

Feng, Xiangdong; Bates, J.K.

1993-01-01

A short summary is given of our studies on the major factors that affect the chemical durability of nuclear waste glasses. These factors include glass composition, solution composition, SA/V (ratio of glass surface area to the volume of solution), radiation, and colloidal formation. These investigations have enabled us to gain a better understanding of the chemical durability of nuclear waste glasses and to accumulate.a data base for modeling the long-term durability of waste glass, which will be used in the risk assessment of nuclear waste disposal. This knowledge gained also enhances our ability to formulate optimal waste glass compositions

PLUGGING AND UNPLUGGING OF WASTE TRANSFER PIPELINES

International Nuclear Information System (INIS)

Ebadian, M.A.

1999-01-01

This project, which began in FY97, involves both the flow loop research on plugging and unplugging of waste transfer pipelines, and the large-scale industrial equipment test of plugging locating and unplugging technologies. In FY98, the related work was performed under the project name ''Mixing, Settling, and Pipe Unplugging of Waste Transfer Lines.'' The mixing, settling, and pipeline plugging and unplugging are critical to the design and maintenance of a waste transfer pipeline system, especially for the High-Level Waste (HLW) pipeline transfer. The major objective of this work is to recreate pipeline plugging conditions for equipment testing of plug locating and removal and to provide systematic operating data for modification of equipment design and enhancement of performance of waste transfer lines used at DOE sites. As the waste tank clean-out and decommissioning program becomes active at the DOE sites, there is an increasing potential that the waste slurry transfer lines will become plugged and unable to transport waste slurry from one tank to another or from the mixing tank to processing facilities. Transfer systems may potentially become plugged if the solids concentration of the material being transferred increases beyond the capability of the prime mover or if upstream mixing is inadequately performed. Plugging can occur due to the solids' settling in either the mixing tank, the pumping system, or the transfer lines. In order to enhance and optimize the slurry's removal and transfer, refined and reliable data on the mixing, sampling, and pipe unplugging systems must be obtained based on both laboratory-scale and simulated in-situ operating conditions

Carbon dioxide assisted sustainability enhancement of pyrolysis of waste biomass: A case study with spent coffee ground.

Science.gov (United States)

Cho, Dong-Wan; Cho, Seong-Heon; Song, Hocheol; Kwon, Eilhann E

2015-01-01

This work mainly presents the influence of CO2 as a reaction medium in the thermo-chemical process (pyrolysis) of waste biomass. Our experimental work mechanistically validated two key roles of CO2 in pyrolysis of biomass. For example, CO2 expedited the thermal cracking of volatile organic compounds (VOCs) evolved from the thermal degradation of spent coffee ground (SCG) and reacted with VOCs. This enhanced thermal cracking behavior and reaction triggered by CO2 directly led to the enhanced generation of CO (∼ 3000%) in the presence of CO2. As a result, this identified influence of CO2 also directly led to the substantial decrease (∼ 40-60%) of the condensable hydrocarbons (tar). Finally, the morphologic change of biochar was distinctive in the presence of CO2. Therefore, a series of the adsorption experiments with dye were conducted to preliminary explore the physico-chemical properties of biochar induced by CO2. Copyright © 2015 Elsevier Ltd. All rights reserved.

The potential of different lime tree (Tilia spp genotypes for phytoextraction of heavy metals

Directory of Open Access Journals (Sweden)

Šijačić-Nikolić Mirjana

2012-01-01

Full Text Available The research of heavy metals contents (Pb, Mn, Zn, Ni, Fe in soil in the area of the National Park „Fruška gora”, along the highway M21 shows lower values for manganese, zinc and iron than the maximum allowed quantity prescribed by law. For nickel and lead it shows higher values than maximum allowed quantity. The heavy metals contents in leaves of lime tree in 12 analyzed genotypes are far below average values in accordance with ECCE with all genotypes except genotype 7 for lead and genotypes 7 and 8 for iron. The results of analysis of variance components show that out of four components (locality, genotype, locality x genotype and error only the interaction between locality and genotype does not contribute to variance. The contents of Pb, Mn, Fe and Zn in leaves is primarily influenced by genotype while Ni contents may be considered a consequence of locality. The selection of genotypes which is able to uptake greater quantities of heavy metals than other genotypes may serve as a solid basis for phytoextraction of heavy metals as a technology by which heavy metals, metalloids and radionuclides are extracted from environment through usage of suitable species and plant genotypes able to uptake and accumulate the given pollutants in parts of plant tissue. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Studying climate change and its influence on the environment: Impacts, adaptation and mitigation

Direct oxidation of strong waste waters, simulating combined wastes in extended-mission space cabins

Science.gov (United States)

Ross, L. W.

1973-01-01

The applications of modern technology to the resolution of the problem of solid wastes in space cabin environments was studied with emphasis on the exploration of operating conditions that would permit lowering of process temperatures in wet oxidation of combined human wastes. It was found that the ultimate degree of degradation is not enhanced by use of a catalyst. However, the rate of oxidation is increased, and the temperature of oxidation is reduced to 400 F.

Enhanced integrated nonthermal treatment system study

International Nuclear Information System (INIS)

Biagi, C.; Schwinkendorf, B.; Teheranian, B.

1997-02-01

The purpose of the Enhanced Nonthermal Treatment Systems (ENTS) study is to evaluate alternative configurations of one of the five systems evaluated in the Integrated Nonthermal Treatment Systems (INTS) study. Five alternative configurations are evaluated. Each is designed to enhance the final waste form performance by replacing grout with improved stabilization technologies, or to improve system performance by improving the destruction efficiency for organic contaminants. AU enhanced systems are alternative configurations of System NT-5, which has the following characteristics: Nonthermal System NT-5: (1) catalytic wet oxidation (CWO) to treat organic material including organic liquids, sludges, and soft (or combustible) debris, (2) thermal desorption of inorganic sludge and process residue, (3) washing of soil and inorganic debris with treatment by CWO of removed organic material, (4) metal decontamination by abrasive blasting, (5) stabilization of treated sludge, soil, debris, and untreated debris with entrained contamination in grout, and (6) stabilization of inorganic sludge, salts and secondary waste in polymer. System NT-5 was chosen because it was designed to treat combustible debris thereby minimizing the final waste form volume, and because it uses grout for primary stabilization. The enhanced nonthermal systems were studied to determine the cost and performance impact of replacing grout (a commonly used stabilization agent in the DOE complex) with improved waste stabilization methods such as vitrification and polymer

Laser Monitoring Of Phytoextraction Enhancement Of Lead Contaminated Soil Adopting EDTA And EDDS

Science.gov (United States)

Hassan, M.; Abdelhamied, M.; Hanafy, A. H.; Fantoni, R.; Harith, M. A.

2011-09-01

Removal of heavy metals (HMs) such as Pb from soil, wastewater, and air is essential for environment and human health. Phytoremediation is a well established technology based on the use of certain green plants for contaminants removal from soil, wastewater as well as air. Scented geranium, Pelargonium zonal, is a flowering plant recently used in HMs removal from contaminated soil. In the present work, EDTA (ethylenediaminetetraacetic acid) and EDDS (S, S-ethylenediaminedisuccinic acid) were used as chemical assistants providing higher Pb availability for extraction by plant roots. Lead was artificially added to the planting media, peatmoss, at different concentrations. Laser induced breakdown spectroscopy (LIBS) was used to follow up Pb relative concentrations in peatmoss as well as plant shoots, at different sampling times during the experiment period. Laser induced chlorophyll fluorescence (LICF), has been also used to evaluate chlorophyll formation and photosynthetic apparatus status in geranium plants. Such measurements were performed on geranium plants grown under various Pb levels, as well as EDTA and EDDS combinations. The combined effect of EDTA and EDDS was found to enhance Pb extraction with time. Good correlation was found between LICF results and chlorophyll (a) (Chl.a) concentrations in plant tissues extracted by chemical analysis.

Phytoextraction based on Indian mustard (Brassica juncea arawali planted on spiked soil by aliquot amount of Lead and Nickel

Directory of Open Access Journals (Sweden)

Leela Kaur

2015-12-01

Full Text Available Phytoextraction is one of the mechanisms of phytoremediation for removal of heavy metals from contaminated soils. The objective of the present study was to investigate the effect of metal chelants, ethelyne diamine tetraacetic acid (EDTA and salicylic acid (SA, on the accumulation of lead and nickel by Indian mustard (Brassica juncea arawali plants in contaminated soil. Plants were treated with Pb and Ni, each at concentrations of 800 mg/l. EDTA and SA were amended at 0.1 M and 1.0 mM respectively. Plants were harvested and oven-dried. Pb and Ni content were estimated using ICP-OES (Varian Vista-MPX CCD Simultaneous ICP-OES. The samples thus prepared were investigated for metals distribution and morphology in different tissues (root, stem and leaf using energy dispersive X-ray analysis (EDAX spectrometer attached to the scanning electron microscope (SEM. Metal distribution study in different tissues (root, stem, leaf was done by SEM/EDS. The results showed that EDTA increased Pb and Ni uptake as compared to SA.

Treatment of organic solid waste for reuse: a step towards zero waste

International Nuclear Information System (INIS)

Ali, M.; Khan, Z.M.; Raja, I.A.

2013-01-01

Large amounts of organic solid wastes are being generated from municipal, industrial and agricultural activities. After necessary processing, the organic solid waste can be reused for agriculture not only as a nutrient supplement for plant growth, but also as a conditioner for seedbed soil. Processed organic wastes may improve soil structure and enhance water and nutrient-holding capacity of the soil, as well as increase the microbial activity within the soil, thereby increasing soil fertility. In this study, problems like undesirably high moisture contents and large volumes per unit weight of the processed organic solid wastes have been addressed through pelletization. Physical properties like durability, percent of fines content, and bulk and particle density of the processed and pelletized organic waste have been investigated, and the optimum values for storage, handling and transportation of the pelletized organic waste have been determined. Three different sizes of extruding sieve (4.35, 6.35 and 7.9 mm) and three different waste-mixing ratios (1:1:2, 1:2:2 and 1:3:3) of farmyard waste, wastewater sludge and sugar industry press mud were used respectively for the production of bio-solid pellets. The physical properties of the palletes show that durability increases by increasing the amount of sewage sludge while fines content, bulk density and unit density decrease. The large sieve size has more durability and less fine content. The results showed that the pelletization technique can be efficiently used by the farmers and appears to be a good option for sustainable management and re-use of organic solid wastes. (author)

Characterization of mixed CH-TRU waste at Argonne-West

International Nuclear Information System (INIS)

Dwight, C.C.; Guay, K.P.; Courtney, J.C.; Higgins, P.J.

1993-01-01

Argonne National Laboratory is participating in the Department of Energy's Waste Isolation Pilot Plant (WIPP) Experimental Test Program by characterizing and repackaging mixed contact-handled transuranic waste. Argonne's initial activities in the Program were described last year at Waste Management '92. Since then, additional waste has been characterized and repackaged, resulting in six bins ready for shipment to WIPP upon the initiation of the bin tests. Lessons learned from these operations are being factored in the design and installation of a new characterization facility, the Enhanced Waste Characterization Facility (EWCF). The objectives of the WIPP Experimental Test Program have also undergone change since last year leading to an accelerated effort to factor sludge sampling capability into the EWCF. Consequently, the initiation of non-sludge operations in the waste characterization chamber has been delayed to Summer 1993 while the sludge sampling modifications are incorporated into the facility. Benefits in operational flexibility, effectiveness, and efficiency and reductions in potential facility and personnel contamination and exposure are expected from the enhanced waste characterization facility within the Hot Fuel Examination Facility at Argonne-West. This paper summarizes results and lessons learned from recent characterization and repackaging efforts and future plans for characterization. It also describes design features and status of the EWCF

Optimization of fly ash incorporation into cow dung-waste paper mixtures for enhanced vermidegradation and nutrient release.

Science.gov (United States)

Mupambwa, Hupenyu A; Mnkeni, Pearson N S

2015-05-01

This study was conducted to establish an appropriate mixture ratio of fly ash (F) to optimized cow dung-waste paper mixtures (CP) to develop a high-quality vermicompost using earthworms (). Fly ash was mixed with cow dung-waste paper mixtures at ratios of (F:CP) 1:1, 1:2, 1:3, 2:1, and 3:1 or CP alone and composted for 14 wk. Olsen P, inorganic N (NO, NO, and NH), C:N ratio, ash content, microbial biomass C, and humification parameters were measured together with scanning electron micrograph images to determine compost maturity. Based on C:N ratio, the extent of vermidegradation of the waste mixtures followed the decreasing order (F:CP) of 1:3 > 1:2 > 1:1 > CP alone > 2:1 > 3:1. Similarly, Olsen P was significantly higher ( percentage increase in extractable P was in the order CP alone > 1:2 > 1:3 > 1:1 > 2:1 > 3:1, with earthworm addition almost doubling P release across the 1:1, 1:2, and CP alone treatments. Fly ash incorporation enhanced conversion of organic N to the plant-available inorganic forms, with the 1:3 treatment resulting in the highest conversion. Scanning electron micrograph images confirmed the extent of vermidegradation reflected by the various humification parameters determined. Fly ash incorporation at the 1:2 ratio proved to be the most appropriate because it allows processing of more fly ash while giving a vermicompost with desirable maturity and nutritional properties. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Assessment of the Efficacy of Chelate-Assisted Phytoextraction of Lead by Coffeeweed (Sesbania exaltata Raf.

Directory of Open Access Journals (Sweden)

Gloria Miller

2008-12-01

Full Text Available Lead (Pb, depending upon the reactant surface, pH, redox potential and other factors can bind tightly to the soil with a retention time of many centuries. Soil-metal interactions by sorption, precipitation and complexation processes, and differences between plant species in metal uptake efficiency, transport, and susceptibility make a general prediction of soil metal bioavailability and risks of plant metal toxicity difficult. Moreover, the tight binding characteristic of Pb to soils and plant materials make a significant portion of Pb unavailable for uptake by plants. This experiment was conducted to determine whether the addition of ethylenediaminetetraacetic acid (EDTA, ethylene glycol tetraacetic acid (EGTA, or acetic acid (HAc can enhance the phytoextraction of Pb by making the Pb soluble and more bioavailable for uptake by coffeeweed (Sesbania exaltata Raf.. Also we wanted to assess the efficacy of chelates in facilitating translocation of the metal into the above-ground biomass of this plant. To test the effect of chelates on Pb solubility, 2 g of Pb-spiked soil (1000 mg Pb/kg dry soil were added to each 15 mL centrifuge tube. Chelates (EDTA, EGTA, HAc in a 1:1 ratio with the metal, or distilled deionized water were then added. Samples were shaken on a platform shaker then centrifuged at the end of several time periods. Supernatants were filtered with a 0.45 μm filter and quantified by inductively coupled plasma-optical emission spectrometry (ICP-OES to determine soluble Pb concentrations. Results revealed that EDTA was the most effective in bringing Pb into solution, and that maximum solubility was reached 6 days after chelate amendment. Additionally, a greenhouse experiment was conducted by planting Sesbania seeds in plastic tubes containing top soil and peat (2:1, v:v spiked with various levels (0, 1000, 2000 mg Pb/kg dry soil of lead nitrate. At six weeks after emergence, aqueous solutions of EDTA and/or HAc (in a 1:1 ratio

Hanford enhanced waste glass characterization. Influence of composition on chemical durability

International Nuclear Information System (INIS)

Fox, K. M.; Edwards, T. B.

2016-01-01

This report provides a review of the complete high-level waste (HLW) and low-activity waste (LAW) data sets for the glasses recently fabricated at Pacific Northwest National Laboratory and characterized at Savannah River National Laboratory (SRNL). The review is from the perspective of relating the chemical durability performance to the compositions of these study glasses, since the characterization work at SRNL focused on chemical analysis and ASTM Product Consistency Test (PCT) performance.

Plume and Dose Modeling Performed to Assess Waste Management Enhancements Associated with Envirocare's Decision to Purchase of an Engineered Rail Rollover Facility Enclosure

International Nuclear Information System (INIS)

Rogers, T.; Clayman, B.

2003-01-01

This paper describes the modeling performed on a proposed enclosure for the existing railcar rollover facility located in Clive, Utah at a radioactive waste disposal site owned and operated by Envirocare of Utah, Inc. (Envirocare). The dose and plume modeling information was used as a tool to justify the decision to make the capital purchase and realize the modeled performance enhancements

Brain-wide pathway for waste clearance captured by contrast-enhanced MRI.

Science.gov (United States)

Iliff, Jeffrey J; Lee, Hedok; Yu, Mei; Feng, Tian; Logan, Jean; Nedergaard, Maiken; Benveniste, Helene

2013-03-01

The glymphatic system is a recently defined brain-wide paravascular pathway for cerebrospinal fluid (CSF) and interstitial fluid (ISF) exchange that facilitates efficient clearance of solutes and waste from the brain. CSF enters the brain along para-arterial channels to exchange with ISF, which is in turn cleared from the brain along para-venous pathways. Because soluble amyloid β clearance depends on glymphatic pathway function, we proposed that failure of this clearance system contributes to amyloid plaque deposition and Alzheimer's disease progression. Here we provide proof of concept that glymphatic pathway function can be measured using a clinically relevant imaging technique. Dynamic contrast-enhanced MRI was used to visualize CSF-ISF exchange across the rat brain following intrathecal paramagnetic contrast agent administration. Key features of glymphatic pathway function were confirmed, including visualization of para-arterial CSF influx and molecular size-dependent CSF-ISF exchange. Whole-brain imaging allowed the identification of two key influx nodes at the pituitary and pineal gland recesses, while dynamic MRI permitted the definition of simple kinetic parameters to characterize glymphatic CSF-ISF exchange and solute clearance from the brain. We propose that this MRI approach may provide the basis for a wholly new strategy to evaluate Alzheimer's disease susceptibility and progression in the live human brain.

Chelant-enhanced heavy metals uptake by Eucalyptus trees under controlled deficit irrigation

Science.gov (United States)

Fine, Pinchas; Rathod, Paresh; Beriozkin, Anna; Ein-Gal, Oz; Hass, Amir

2014-05-01

Enhancement of phytoremediation of heavy metal polluted soils employs organic ligands, aimed to solubilize, phytoextract and translocate metals into the canopy. The use of more persistent chelants (e.g. EDTA) is phasing out due to concerns over their role in the environment. We tested the hypothesis that controlled deficit irrigation (CDI) of the fast growing, salinity resistant Eucalyptus camaldulensis coupled with timely EDTA application enhances sediment phytoremediation while minimizing leaching of metal complexes below the root-zone. This was tested in 220-L lysimeters packed with sand mixed with metals polluted biosolids. One year old trees were brought under CDI with tap or RO water for two growing seasons. EDTA, EDDS and citric acid fertigation at 2 mM started in each May for 2.5-3.5 months, and prescribed soil leaching and sampling of tree leaves started thereafter. While all 3 chelants solubilized biosolids metal in batch extraction (EDDS often being the more efficient), EDTA was the only to increased metal concentrations both in the soil solution and in the Eucalyptus leaves. The average concentrations in the soil solution and in the leaves, in the EDTA vs. control (chelant-free) treatments, all respectively, were: Cd - 200 mg L-1 vs. 1.0, and 67 vs. 21 mg kg-1; Cu: 90 vs. 1.5 mg L-1, and 17 vs. 3.0 mg kg-1; Cr: 4.0 vs. 1.4 mg L-1, and 3.0 vs. 1.0 mg kg-1; Ni: 60 mg L-1 vs. 14, and 20 vs. 6.0 mg kg-1; Pb: >44 vs. 0.1 mg L-1, and 9.0 vs. 1.0 mg kg-1; and Zn: 650 vs. 4.0 mg L-1 and 200 vs. 70 mg kg-1. While EDDS was undetectable in all the leachates, EDTA concentrated to up to 100 mM. At 10 mM soil solution concentration, EDDS half-life in acclimated lysimeter media was 5-11 days and that of EDTA was ≥27-d. The study suggests that sustainable phytostabilization and phytoextraction of heavy metals are achievable under CDI with EDTA augmentation at low dose. This was yet futile with the biodegradable EDDS and citric acid. CDI with RO water further widened

Hijacking membrane transporters for arsenic phytoextraction

Science.gov (United States)

LeBlanc, Melissa S.; McKinney, Elizabeth C.; Meagher, Richard B.; Smith, Aaron P.

2012-01-01

Arsenic is a toxic metalloid and recognized carcinogen. Arsenate and arsenite are the most common arsenic species available for uptake by plants. As an inorganic phosphate (Pi) analog, arsenate is acquired by plant roots through endogenous Pi transport systems. Inside the cell, arsenate is reduced to the thiol-reactive form arsenite. Glutathione (GSH)-conjugates of arsenite may be extruded from the cell or sequestered in vacuoles by members of the ATP-binding cassette (ABC) family of transporters. In the present study we sought to enhance both plant arsenic uptake through Pi transporter overexpression, and plant arsenic tolerance through ABC transporter overexpression. We demonstrate that Arabidopsis thaliana plants overexpressing the high-affinity Pi transporter family members, AtPht1;1 or AtPht1;7, are hypersensitive to arsenate due to increased arsenate uptake. These plants do not exhibit increased sensitivity to arsenite. Co-overexpression of the yeast ABC transporter YCF1 in combination with AtPht1;1 or AtPht1;7 suppresses the arsenate-sensitive phenotype while further enhancing arsenic uptake. Taken together, our results support an arsenic transport mechanism in which arsenate uptake is increased through Pi transporter overexpression, and arsenic tolerance is enhanced through YCF1-mediated vacuolar sequestration. This work substantiates the viability of coupling enhanced uptake and vacuolar sequestration as a means for developing a prototypical engineered arsenic hyperaccumulator. PMID:23108027

Phytoextraction of soil trace elements by willow during a phytoremediation trial in Southern Québec, Canada.

Science.gov (United States)

Courchesne, François; Turmel, Marie-Claude; Cloutier-Hurteau, Benoît; Constantineau, Simon; Munro, Lara; Labrecque, Michel

2017-06-03

The phytoextraction of the trace elements (TEs) As, Cd, Cu, Ni, Pb, and Zn by willow cultivars (Fish Creek, SV1 and SX67) was measured during a 3-year field trial in a mildly contaminated soil. Biomass ranged from 2.8 to 4.4 Mg/ha/year at 30,000 plants/ha. Shoots (62%) were the main component followed by leaves (23%) and roots (15%). Biomass was positively linked to soluble soil dissolved organic carbon, K, and Mg, while TEs, not Cd and Zn, had a negative effect. The TE concentration ranking was: Zn > Cu > Cd > Ni, Pb > As, and distribution patterns were: (i) minima in shoots (As, Ni), (ii) maxima in leaves (Cd, Zn), or (iii) maxima in roots (Cu, Pb). Correlations between soil and plant TE were significant for the six TEs in roots. The amounts extracted were at a maximum for Zn, whereas Fish Creek and SV1 extracted more TE than SX67. More than 60% (91-94% for Cd and Zn) of the total TE was in the aboveground parts. Uptake increased with time because of higher biomass. Fertilization, the selection of cultivars, and the use of complementary plants are required to improve productivity and Cd and Zn uptake.

Waste recycling: utilization of coffee grounds and kitchen waste in vermicomposting.

Science.gov (United States)

Adi, A J; Noor, Z M

2009-01-01

Vermicomposting using Lumbricus rubellus for 49 days was conducted after 21 days of pre-composting. Three different combination of treatments were prepared with eight replicates for each treatment namely cow dung: kitchen waste in 30:70 ratio (T(1)), cow dung: coffee grounds in 30:70 ratio (T(2)), and cow dung: kitchen waste: coffee grounds in 30:35:35 ratio (T(3)). The multiplication of earthworms in terms of numbers and weight were measured at the end of vermicomposting. Consequently, only T(2) showed significant increase (from it initial stage) compared to other treatments. The presence of coffee grounds in T(2) and T(3) showed higher percentage of nutrient elements in vermicompost produced. The data reveal that coffee grounds can be decomposed through vermicomposting and help to enhance the quality of vermicompost produced rather than sole use of kitchen waste in vermicomposting.

Enhanced stabilisation of municipal solid waste in bioreactor landfills

NARCIS (Netherlands)

Valencia Vázquez, R.

2008-01-01

The increasing development and urbanization of the society has led to an increase per-capita production of municipal solid waste (MSW) materials. These MSW materials are of organic and inorganic nature that can be of rapidly, moderately and slowly biodegradable or inert characteristics. With regard

Gold Phytomining: A New Idea for Enviromental Sustainablity in Indonesia

Directory of Open Access Journals (Sweden)

Baiq Dewi Krisnayanti

2014-07-01

Full Text Available DOI: 10.17014/ijog.v1i1.171New technology is needed to protect the safety and health of communities and the environment at ASGM locations in Indonesia. This technology must be simple, cheap, easy to operate, and financially rewarding. A proven option that should be promoted is phytoextraction, a farming activity that could develop agriculture as an alternative livelihood in ASGM areas. This is a technology where plants are used to extract metals from waste rock, soil, or water. These metals can be recovered from the plant in its pure form, then be sold or recycled. Gold phytoextraction is a commercially available technology, while an international research has shown that phytoextraction will also work for mercury. In the context of this idea, tailings would be contained in ‘farming areas’ and cropped using phytoextraction technology. Gold and mercury would be extracted in the crops, with the remaining mercury burden of the tailings becoming adsorbed to soil constituents. The system would be financially rewarding to ‘gold farmers’. The economic value of this scenario could facilitate the clean-up and management of mercury pollution, reducing the movement of mercury from tailings into soil, water, and plants, thereby mitigating environmental and human risk in the mining areas. The goal of the described research is to promote agriculture as an alternative livelihood in ASGM areas. The gold value of the phytoremediation crop should provide a cash incentive to artisanal farmers who develop this new agricultural enterprise. The benefits will be social, environmental, and economic, as opportunities for education, employment, new business, the containment of toxic mercury, food safety and security, and revenue are all realized.

Advances in agronomic management of phytoremediation: methods and results from a 10-year study of metal-polluted soils

Directory of Open Access Journals (Sweden)

Teofilo Vamerali

2012-11-01

Full Text Available Among green technologies addressed to metal pollution, phytoextraction has received increasing attention in recent years as an alternative to physical and chemical methods of decontamination. Since 1998, as part of an Italian multidisciplinary research team on phytoremediation, we have been carrying out several agronomic investigations with field crops in agricultural soil and pyrite waste, both markedly contaminated by heavy metals. Phytoextraction was rarely an efficient process, requiring a long time even to remove merely the bioavailable metal fraction, but the great metal stock in roots suggests exploring the effectiveness of long-term in planta stabilisation. Poor above-ground productivity was the main factor constraining metal removals, especially in wastes. Without assisting the process, only zinc (Zn, manganese (Mn and copper (Cu were harvested by the canopy in substantial amounts, with an estimated maximum of ~8 kg of metals from an hectare base with rapeseed in the agricultural soil and only 0.33 kg with fodder radish in pyrite waste. Root growth was a key trait in species and genotype selection, in view of the close relationship between root length and metal uptake. The auxins, humic acids and chelators tested on the model plant fodder radish generally increased metal concentrations in plant tissues, but reduced growth and removals. It is currently concluded that phytoremediation efficiency with crop species may be improved through increased productivity by suitable soil management, involving mineral and organic fertilisation, contaminant dilution, soil capping, and metal immobilisation with inorganics and biochar.

Conditioning of alpha bearing wastes

International Nuclear Information System (INIS)

1991-01-01

Alpha bearing wastes are generated during the reprocessing of spent fuel, mixed oxide fuel fabrication, decommissioning and other activities. The safe and effective management of these wastes is of particular importance owing to the radiotoxicity and long lived characteristics of certain transuranic (TRU) elements. The management of alpha bearing wastes involves a number of stages which include collection, characterization, segregation, treatment, conditioning, transport, storage and disposal. This report describes the currently available matrices and technologies for the conditioning of alpha wastes and relates them to their compatibility with the other stages of the waste management process. The selection of a specific immobilization process is dependent on the waste treatment state and the subsequent handling, transport, storage and disposal requirements. The overall objectives of immobilization are similar for all waste producers and processors, which are to produce: (a) Waste forms with sufficient mechanical, physical and chemical stability to satisfy all stages of handling, transport and storage (referred to as the short term requirements), and (b) Waste forms which will satisfy disposal requirements and inhibit the release of radionuclides to the biosphere (referred to as the long term requirements). Cement and bitumen processes have already been successfully applied to alpha waste conditioning on the industrial scale in many of the IAEA Member States. Cement systems based on BFS and pozzolanic cements have emerged as the principal encapsulation matrices for the full range of alpha bearing wastes. Alternative technologies, such as polymers and ceramics, are being developed for specific waste streams but are unlikely to meet widespread application owing to cost and process complexity. The merits of alpha waste conditioning are improved performance in transport, storage and disposal combined with enhanced public perception of waste management operations. These

Decontamination of soils polluted with heavy metals using plants as determined by nuclear technique

International Nuclear Information System (INIS)

Lotfy, S.M

2010-01-01

The objectives of this work were three folds. First, to study the mobility and fate of heavy metals in two polluted sites (Mostorud soil, irrigated with contaminated water for more than 30 years and El-Gabal EL-Asfar soil, subjected to sewage effluent irrigation for more than 50 years) utilizing a modified tessier's sequential extraction procedure to evaluate the effect of total metal concentrations on metal partitioning into different fractions. Second, to evaluate the efficiency of some plant species (sunflower, cotton, penakium, Napier grass, and Squash) to extract heavy metals out of polluted soils. Third, to enhance the phyto-extraction of heavy metals by sunflower plant using some chemical chelators (citric acids, EDTA, and Ammonium nitrate) in order to improve the remediation of pollutants as well as to protect soil quality.It was observed that the distribution of heavy metals in various chemical fractions depends on the total heavy metals content. The distribution of heavy metals forms in the studied soils was in the following decreasing order: residual > Fe-Mn oxides > carbonates > organic > exchangeable > water soluble.Either higher metal accumulation in shoots or enhanced metal accumulation in roots was mainly due to improved phyto-extraction or rhizo-filtration efficiency, respectively. Heavy metals accumulation in shoots and roots of the investigated plant species was as follow: sunflower > cotton > penakium > Napier grass > Squash with a lower order of magnitude. Sunflower showed superiority for heavy metals extraction.Application of chemical chelators (soil amendments) enhanced the phyto-extraction efficiency of heavy metals by sunflower in both Mostorud and El-Gabal El-Asfar soils. Citric acid enhanced metals accumulation in shoots and roots more than EDTA and ammonium nitrate. Citric acid with rate of 20 m mole/kg soil was the best chelators to enhance phyto- extraction of heavy metals by sunflower.

Waste Pickers: Why are they there?

CSIR Research Space (South Africa)

Oelofse, Suzanna HH

2011-07-01

Full Text Available of pickers ? Increase job stability and earnings of pickers ? Enhance the effectiveness of their contribution to waste management ? Entrepreneural activities as observed require a level of organisation in the informal sector ? Research are required... about 4 400 pickers operational in Johannesburg 15/07/2011 3 ? CSIR 2011 www.csir.co.za Informal sector waste pickers and entrepreneurs ? Do not pay taxes ? No trading license ? No social welfare or government insurance scheme...

Waste management, waste resource facilities and waste conversion processes

International Nuclear Information System (INIS)

Demirbas, Ayhan

2011-01-01

In this study, waste management concept, waste management system, biomass and bio-waste resources, waste classification, and waste management methods have been reviewed. Waste management is the collection, transport, processing, recycling or disposal, and monitoring of waste materials. A typical waste management system comprises collection, transportation, pre-treatment, processing, and final abatement of residues. The waste management system consists of the whole set of activities related to handling, treating, disposing or recycling the waste materials. General classification of wastes is difficult. Some of the most common sources of wastes are as follows: domestic wastes, commercial wastes, ashes, animal wastes, biomedical wastes, construction wastes, industrial solid wastes, sewer, biodegradable wastes, non-biodegradable wastes, and hazardous wastes.

Cadmium and Zn availability as affected by pH manipulation and its assessment by soil extraction, DGT and indicator plants

International Nuclear Information System (INIS)

Muhammad, Iqbal; Puschenreiter, Markus; Wenzel, Walter W.

2012-01-01

Manipulation of soil pH by soil additives and / or rhizosphere processes may enhance the efficiency of metal phytoextraction. Here we report on the effect of nitric acid additions to four polluted soils on Cd and Zn concentrations in soil solution (C soln ) and 0.005 M Ca(NO 3 ) 2 extracts, and related changes in the diffusive fluxes and resupply of the metals as assessed by diffusive gradients in thin films (DGT). The responses of these chemical indicators of bioavailability were compared to metal uptake in two indicator plant species, common dandelion (Taraxacum officinale F.H. Wigg) and narrow leaf plantain (Plantago lanceolata L.) grown for 75 days in a pot experiment. Lowering soil pH increased C soln , the 0.005 M Ca(NO 3 ) 2 -soluble fractions and the DGT-measured Cd and Zn concentrations (C DGT ) in the experimental soils. This was associated with enhanced uptake of Cd and Zn on soils acidified to pH 4.5 whereas plants did not survive at pH 3.5. Toxicity along with decreased kinetics of metal resupply (calculated by the 2D DIFS model) in the strong acidification treatment suggests that moderate acidification is more appropriate to enhance the phytoextraction process. Each of the chemical indicators of bioavailability predicted well (R 2 > 0.70) the Cd and Zn concentrations in plantain shoots but due to metal toxicity not for dandelion. Concentration factors, i.e. the ratio between metal concentrations in shoots and in soil solution (CF) indicate that Cd and Zn uptake in plantain was not limited by diffusion which may explain that DGT did not perform better than C soln . However, DGT is expected to predict plant uptake better in diffusion-limited conditions such as in the rhizosphere of metal-accumulating phytoextraction crops. - Highlights: ► The effect of soil acidification was assessed for four Zn and Cd polluted soils. ► For some soils moderate acidification could enhance the metal uptake efficiency. ► Chemical assessment of bioavailability using

Cadmium and Zn availability as affected by pH manipulation and its assessment by soil extraction, DGT and indicator plants

Energy Technology Data Exchange (ETDEWEB)

Muhammad, Iqbal; Puschenreiter, Markus, E-mail: markus.puschenreiter@boku.ac.at; Wenzel, Walter W.

2012-02-01

Manipulation of soil pH by soil additives and / or rhizosphere processes may enhance the efficiency of metal phytoextraction. Here we report on the effect of nitric acid additions to four polluted soils on Cd and Zn concentrations in soil solution (C{sub soln}) and 0.005 M Ca(NO{sub 3}){sub 2} extracts, and related changes in the diffusive fluxes and resupply of the metals as assessed by diffusive gradients in thin films (DGT). The responses of these chemical indicators of bioavailability were compared to metal uptake in two indicator plant species, common dandelion (Taraxacum officinale F.H. Wigg) and narrow leaf plantain (Plantago lanceolata L.) grown for 75 days in a pot experiment. Lowering soil pH increased C{sub soln}, the 0.005 M Ca(NO{sub 3}){sub 2}-soluble fractions and the DGT-measured Cd and Zn concentrations (C{sub DGT}) in the experimental soils. This was associated with enhanced uptake of Cd and Zn on soils acidified to pH 4.5 whereas plants did not survive at pH 3.5. Toxicity along with decreased kinetics of metal resupply (calculated by the 2D DIFS model) in the strong acidification treatment suggests that moderate acidification is more appropriate to enhance the phytoextraction process. Each of the chemical indicators of bioavailability predicted well (R{sup 2} > 0.70) the Cd and Zn concentrations in plantain shoots but due to metal toxicity not for dandelion. Concentration factors, i.e. the ratio between metal concentrations in shoots and in soil solution (CF) indicate that Cd and Zn uptake in plantain was not limited by diffusion which may explain that DGT did not perform better than C{sub soln}. However, DGT is expected to predict plant uptake better in diffusion-limited conditions such as in the rhizosphere of metal-accumulating phytoextraction crops. - Highlights: Black-Right-Pointing-Pointer The effect of soil acidification was assessed for four Zn and Cd polluted soils. Black-Right-Pointing-Pointer For some soils moderate acidification could

Multibarrier waste forms. Part III: Process considerations

International Nuclear Information System (INIS)

Lokken, R.O.

1979-10-01

The multibarrier concept for the solidification and storage of radioactive waste utilizes up to three barriers to isolate radionuclides from the environment: a solidified waste inner core, an impervious coating, and a metal matrix. The coating and metal matrix give the composite waste form enhanced inertness with improvements in thermal stability, mechanical strength, and leach resistance. Preliminary process flow rates and material costs were evaluated for four multibarrier waste forms with the process complexity increasing thusly: glass marbles, uncoated supercalcine, glass-coated supercalcine, and PyC/Al 2 O 3 -coated supercalcine. This report discusses the process variables and their effect on optimization of product quality, processing simplicity, and material cost. 11 figures, 2 tables

A preliminary evaluation of alternatives for disposal of INEL low-level waste and low-level mixed waste

International Nuclear Information System (INIS)

Smith, T.H.; Roesener, W.S.; Jorgenson-Waters, M.J.

1993-07-01

The Mixed and Low-Level Waste Disposal Facility (MLLWDF) project was established in 1992 by the US Department of Energy Idaho Operations Office to provide enhanced disposal capabilities for Idaho National Engineering Laboratory (INEL) low-level mixed waste and low-level waste. This Preliminary Evaluation of Alternatives for Disposal of INEL Low-Level Waste and Low-Level Mixed Waste identifies and evaluates-on a preliminary, overview basis-the alternatives for disposal of that waste. Five disposal alternatives, ranging from of no-action'' to constructing and operating the MLLWDF, are identified and evaluated. Several subalternatives are formulated within the MLLWDF alternative. The subalternatives involve various disposal technologies as well as various scenarios related to the waste volumes and waste forms to be received for disposal. The evaluations include qualitative comparisons of the projected isolation performance for each alternative, and facility, health and safety, environmental, institutional, schedule, and rough order-of-magnitude life-cycle cost comparisons. The performance of each alternative is evaluated against lists of ''musts'' and ''wants.'' Also included is a discussion of other key considerations for decisionmaking. The analysis of results indicated further study is necessary to obtain the best estimate of long-term future waste volume and characteristics from the INEL Environmental Restoration activities and the expanded INEL Decontamination and Decommissioning Program

The Reclamation of Tailing Area Reclamation in The Mining Area with Forages, is it Possible?

Directory of Open Access Journals (Sweden)

N D Purwantari

2007-09-01

Full Text Available Tailings are what’s left over from mining. The rock where copper, gold, silver and other minerals found is ground up into fine particles so that the valuable material can be taken out and refined. The solid waste would affect the environment physically and biologically. Characteristics of tailing are high porosity with low water holding capacity, poor organic matter, poor macro and micro nutrients and no microorganism activity. Therefore, it takes time and requires strategy to manage and change them to a more productive area. Many technologies have been applied to rehabilitate tailing for agriculture. The technologies including the use of manure, compost, mulch, biosolid, chemical fertilizer, microorganism (bacteria, mycorhiza and phytoremediation. Phytoremediation is the use of plants to remediate selected contaminants in the contaminated soil, sludge, sediment, water (ground, surface, waste water. Phytoremediation encompasses a number of different methods that can lead to contaminant degradation, removal or immobilization. Those methods including phytodegradation/rhizodegradation, phytoextraction, phytovolatilization and phytostabilization. The phytoextraction is inexpensive compared with the conventional technology. Some forages have been used for phytoremediation such as Paspalum notatum (Bahia grass, Vetiveria zizonoides (Vetiver grass, Cynodon dactylon (Bermuda grass, since they have been known as heavy metal hyperaccumulator plant.

Pig manure vermicompost (PMVC) can improve phytoremediation of Cd and PAHs co-contaminated soil by Sedum alfredii

Science.gov (United States)

Purpose Main challenge of phytoremediation of co-contaminated soils is developing strategies for efficient and simultaneous removal of multiple pollutants. A pot experiment was conducted to investigate the potential for enhanced phytoextraction of cadmium (Cd) by Sedum alfredii and dissipation of po...

A Study on promotion of utilizing waste energy

Energy Technology Data Exchange (ETDEWEB)

Ahn, Jae Ho [Korea Energy Economics Institute, Euiwang (Korea)

1999-01-01

The utilization of waste energy occupying over 80% of alternative energy has been an important issue with the trend of large-sized waste incinerator. The object of this study is to seek the methods for the active application of waste energy, which is produced at the process of waste generation and disposal. It is expected to help energy saving, foreign currency saving and prevent environmental pollution by utilizing alternative energy actively. It should have basic information, related information for examining technical feasibility, and feasibility examination of the surroundings for developing the demand place. Moreover, it should enhance the energy saving by recommending use of waste energy with introducing recommendation system of installing waste energy collection system. It should also consider the support of the introduction of waste energy system as well as the aspect of regional energy policy. In addition, the development and distribution of applied technology for waste energy are needed. (author). 36 refs., 4 figs., 77 tabs.

47{sup th} Annual meeting on nuclear technology (AMNT 2016). Key Topics / Enhanced safety and operation excellence and decommissioning experience and Waste management solutions

Energy Technology Data Exchange (ETDEWEB)

Salnikova, Tatiana [AREVA GmbH, Erlangen (Germany); Schaffrath, Andreas [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Garching (Germany)

2016-10-15

Summary report on the Key Topics ''Enhanced Safety and Operation Excellence'' and ''Decommissioning Experience and Waste Management Solutions'' of the 47{sup th} Annual Conference on Nuclear Technology (AMNT 2016) held in Hamburg, 10 to 12 May 2016. Other Sessions of AMNT 2016 have been and will be covered in further issues of atw.

Portable sensor for hazardous waste

Energy Technology Data Exchange (ETDEWEB)

Piper, L.G.; Fraser, M.E.; Davis, S.J. [Physical Sciences Inc., Andover, MA (United States)

1995-10-01

We are beginning the second phase of a three and a half year program designed to develop a portable monitor for sensitive hazardous waste detection. The ultimate goal of the program is to develop our concept to the prototype instrument level. Our monitor will be a compact, portable instrument that will allow real-time, in situ, monitoring of hazardous wastes. This instrument will be able to provide the means for rapid field screening of hazardous waste sites to map the areas of greatest contamination. Remediation efforts can then focus on these areas. Further, our instrument can show whether cleanup technologies are successful at reducing hazardous materials concentrations below regulated levels, and will provide feedback to allow changes in remediation operations, if necessary, to enhance their efficacy.

Rock-welding materials for deep borehole nuclear waste disposal.

Energy Technology Data Exchange (ETDEWEB)

Yang, Pin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wang, Yifeng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rodriguez, Mark A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brady, Patrick Vane [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Swift, Peter N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-11-01

The concept of deep borehole nuclear waste disposal has recently been proposed. Effective sealing of a borehole after waste emplacement is generally required. In a high temperature disposal mode, the sealing function will be fulfilled by melting the ambient granitic rock with waste decay heat or an external heating source, creating a melt that will encapsulate waste containers or plug a portion of the borehole above a stack of the containers. However, there are certain drawbacks associated with natural materials, such as high melting temperatures, slow crystallization kinetics, the resulting sealing materials generally being porous with low mechanical strength, insufficient adhesion to waste container surface, and lack of flexibility for engineering controls. Here we show that natural granitic materials can be purposefully engineered through chemical modifications to enhance the sealing capability of the materials for deep borehole disposal. This work systematically explores the effect of chemical modification and crystallinity (amorphous vs. crystalline) on the melting and crystallization processes of a granitic rock system. A number of engineered granitic materials have been obtained that have decreased melting points, enhanced viscous densification, and accelerated recrystallization rates without compromising the mechanical integrity of the materials.

Enhancement of lipase catalyzed-fatty acid methyl esters production from waste activated bleaching earth by nullification of lipase inhibitors.

Science.gov (United States)

Dwiarti, Lies; Ali, Ehsan; Park, Enoch Y

2010-01-01

This study sought to identify inhibitory factors of lipase catalyzed-fatty acid methyl esters (FAME) production from waste activated bleaching earth (wABE). During the vegetable oil refinery process, activated bleaching earth (ABE) is used for removing the impure compounds, but adsorbs vegetable oil up to 35-40% as on a weight basis, and then the wABE is discarded as waste material. The impurities were extracted from the wABE with methanol and evaluated by infra-red (IR) spectroscopy, which revealed that some were chlorophyll-plant pigments. The chlorophylls inhibited the lipase during FAME conversion from wABE. The inhibition by a mixture of chlorophyll a and b was found to be competitive. The inhibition of the enzymatic hydrolysis of waste vegetable oil contained in wABE by chlorophyll a alone was competitive, while the inhibition by chlorophyll b alone was non-competitive. Furthermore, the addition of a small amount of alkali nullified this inhibitory effect and accelerated the FAME production rate. When 0.9% KOH (w/w wABE) was added to the transesterification reaction with only 0.05% lipase (w/w wABE), the maximum FAME production rate improved 120-fold, as compared to that without the addition of KOH. The alkali-combined lipase significantly enhanced the FAME production rate from wABE, in spite of the presence of the plant pigments, and even when a lower amount of lipase was used as a catalyst.

Biodegradation of an oily bilge waste using algae

Energy Technology Data Exchange (ETDEWEB)

Carpenter, M.J.

1987-01-01

A mixed community of microogranisms was collected from the harbor at the North Island Navy Base and was monitored in a test ecosystem containing an oily bilge waste obtained from off-loading ships. Cultures were examined in the presence and absence of the algae. It was thought that the algae might enhance the degradation of the oil waste by providing oxygen and possibly a nutrient source from dying phytoplankton for the bacterial community. The change in community structure was monitored by isolating the various groups of organisms and determining the biomass change over time for the algae, bacteria and yeasts/fungi subjected to the bilge waste. The biomass (i.e., colony forming units) of the yeasts and fungi increased 100 fold in a 6 week test period. The community containing only the bacteria and fungi/yeasts lost the fungal component of the population, although active bacteria biomass increased more than 10 fold during exposure to the waste. The test ecosystem was subjected to a radiolabeled compound (/sup 14/C-phenol) and bilge waste mixture to ascertain the ability of the communities to mineralize the phenol and/or assimilate the labeled hydrocarbon. The community containing the algae started mineralizing the phenol (measure by /sup 14/CO/sub 2/ production) 24 hours after exposure to the waste/phenol mixture. The bacteria/yeast-fungi community had a lag period of 384 hours before extensive catabolism of the labeled compound occurred. Current data indicate algae may enhance the biodegradation rate of oil bilge waste in a mixed microbial community.

Managing the nation's commercial high-level radioactive waste

International Nuclear Information System (INIS)

1985-03-01

This report presents the findings and conclusions of OTA's analysis of Federal policy for the management of commercial high-level radioactive waste. It is intended to contribute to the implementation of Nuclear Waste Policy Act of 1982 (NWPA). The major conclusion of that review is that NWPA provides sufficient authority for developing and operating a waste management system based on disposal in geologic repositories. Substantial new authority for other facilities will not be required unless major unexpected problems with geologic disposal are encountered. OTA also concludes that DOE's Draft Mission Plan published in 1984 falls short of its potential for enhancing the credibility and acceptability of the waste management program

Waste Information Management System-2012 - 12114

Energy Technology Data Exchange (ETDEWEB)

Upadhyay, H.; Quintero, W.; Shoffner, P.; Lagos, L.; Roelant, D. [Applied Research Center, Florida International University, 10555 West Flagler Street, Suite 2100, Miami, FL 33174 (United States)

2012-07-01

replaced the historic process of each DOE site gathering, organizing, and reporting their waste forecast information utilizing different databases and display technologies. In addition, WIMS meets DOE's objective to have the complex-wide waste forecast and transportation information available to all stakeholders and the public in one easy-to-navigate system. The enhancements to WIMS made since its initial deployment include the addition of new DOE sites and facilities, an updated waste and transportation information, and the ability to easily display and print customized waste forecast, the disposition maps, GIS maps and transportation information. The system also allows users to customize and generate reports over the web. These reports can be exported to various formats, such as Adobe{sup R} PDF, Microsoft Excel{sup R}, and Microsoft Word{sup R} and downloaded to the user's computer. Future enhancements will include database/application migration to the next level. A new data import interface will be developed to integrate 2012-13 forecast waste streams. In addition, the application is updated on a continuous basis based on DOE feedback. (authors)

Enhanced methane yield by co-digestion of sewage sludge with micro-algae and catering waste leachate.

Science.gov (United States)

2018-04-04

The co-digestion of different wastes is a promising concept to improve methane generation during anaerobic process. However, the anaerobic co-digestion of catering waste leachate with algal biomass and sewage sludge has not been studied to date. This work investigated the methane generation by the anaerobic co-digestion of different mixtures of catering waste leachate, micro-algal biomass, and sewage sludge. Co-digestion of waste mixture containing equal ratios of three substrates had 39.31% higher methane yield than anaerobic digestion of raw sludge. This was possibly due to a proliferation of methanogens during the co-digestion period induced by multi-phase digestion of different wastes with different degrees of digestibility. Therefore, co-digestion of catering waste leachate, micro-algal biomass, and sewage sludge appears to be an efficient technology for energy conversion from waste resources. The scientific application of this co-digestion technology with these three substrates may play a role in solving important environmental issues of waste management.

Hydrogen from food processing wastes via photofermentation using Purple Non-sulfur Bacteria (PNSB) – A review

International Nuclear Information System (INIS)

Ghosh, Shiladitya; Dairkee, Umme Kulsoom; Chowdhury, Ranjana; Bhattacharya, Pinaki

2017-01-01

Highlights: • Food processing wastes/wastewaters are potential feedstocks for PNSB-bioH_2 systems. • Several bottlenecks exist in efficient usage of food processing wastes/wastewaters by PNSBs. • Pretreatment of feedstocks is a challenging issue. • Genetic modification significantly enhances the H_2 outcome of PNSBs. • Food waste/wastewater - PNSB is a sustainable combination for production of H_2. - Abstract: Purple non-sulfur bacteria (PNSB) mediated production of biohydrogen utilizing solid food waste and food processing wastewater possess enormous potential to be implemented as an ideal “green energy technology”. This paper reviews the current state-of-the-art utilization of solid wastes and wastewaters of several food and beverage processing industries in photofermentative H_2 production systems. Detailed accounts of the complex composition of various solid food wastes and food processing wastewaters along with the pretreatments used for enhancement of H_2 production by PNSBs have been presented. Factors like compositional complexity, presence of inhibitory compounds and resistance to light penetration are identified as the prime bottlenecks hindering the efficient utilization of food waste and wastewaters in photofermentative H_2 production. Genetic manipulation of the PNSBs to overcome the inherent metabolic complications has been discussed as a probable amelioration strategy for enhancement of H_2 yield. Based on profound discussions the scopes for upgradation of the photofermentative biohydrogen systems using food waste/wastewater have been highlighted and recommended for the overall enhancement of the sustainability of the processes.

Zero-valent iron enhanced methanogenic activity in anaerobic digestion of waste activated sludge after heat and alkali pretreatment.

Science.gov (United States)

Zhang, Yaobin; Feng, Yinghong; Quan, Xie

2015-04-01

Heat or alkali pretreatment is the effective method to improve hydrolysis of waste sludge and then enhance anaerobic sludge digestion. However the pretreatment may inactivate the methanogens in the sludge. In the present work, zero-valent iron (ZVI) was used to enhance the methanogenic activity in anaerobic sludge digester under two methanogens-suppressing conditions, i.e. heat-pretreatment and alkali condition respectively. With the addition of ZVI, the lag time of methane production was shortened, and the methane yield increased by 91.5% compared to the control group. The consumption of VFA was accelerated by ZVI, especially for acetate, indicating that the acetoclastic methanogenesis was enhanced. In the alkali-condition experiment, the hydrogen produced decreased from 27.6 to 18.8 mL when increasing the ZVI dosage from 0 to 10 g/L. Correspondingly, the methane yield increased from 1.9 to 32.2 mL, which meant that the H2-utilizing methanogenes was enriched. These results suggested that the addition of ZVI into anaerobic digestion of sludge after pretreated by the heat or alkali process could efficiently recover the methanogenic activity and increase the methane production and sludge reduction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of autochthonous microbial consortia for enhanced phytoremediation of salt-marsh sediments contaminated with cadmium.

Science.gov (United States)

Teixeira, Catarina; Almeida, C Marisa R; Nunes da Silva, Marta; Bordalo, Adriano A; Mucha, Ana P

2014-09-15

Microbial assisted phytoremediation is a promising, though yet poorly explored, new remediation technique. The aim of this study was to develop autochthonous microbial consortia resistant to cadmium that could enhance phytoremediation of salt-marsh sediments contaminated with this metal. The microbial consortia were selectively enriched from rhizosediments colonized by Juncus maritimus and Phragmites australis. The obtained consortia presented similar microbial abundance but a fairly different community structure, showing that the microbial community was a function of the sediment from which the consortia were enriched. The effect of the bioaugmentation with the developed consortia on cadmium uptake, and the microbial community structure associated to the different sediments were assessed using a microcosm experiment. Our results showed that the addition of the cadmium resistant microbial consortia increased J. maritimus metal phytostabilization capacity. On the other hand, in P. australis, microbial consortia amendment promoted metal phytoextraction. The addition of the consortia did not alter the bacterial structure present in the sediments at the end of the experiments. This study provides new evidences that the development of autochthonous microbial consortia for enhanced phytoremediation of salt-marsh sediments contaminated with cadmium might be a simple, efficient, and environmental friendly remediation procedure. Development of autochthonous microbial consortia resistant to cadmium that enhanced phytoremediation by salt-marsh plants, without a long term effect on sediment bacterial diversity. Copyright © 2014 Elsevier B.V. All rights reserved.

Bio-extraction of precious metals from urban solid waste

Science.gov (United States)

Das, Subhabrata; Natarajan, Gayathri; Ting, Yen-Peng

2017-01-01

Reduced product lifecycle and increasing demand for electronic devices have resulted in the generation of huge volumes of electronic waste (e-waste). E-wastes contain high concentrations of toxic heavy metals, which have detrimental effects on health and the environment. However, e-wastes also contain significant concentrations of precious metals such as gold, silver and palladium, which can be a major driving force for recycling of urban waste. Cyanogenic bacteria such as Chromobacterium violaceum generate cyanide as a secondary metabolite which mobilizes gold into solution via a soluble gold-cyanide complex. However, compared to conventional technology for metal recovery, this approach is not effective, owing largely to the low concentration of lixiviants produced by the bacteria. To overcome the challenges of bioleaching of gold from e-waste, several strategies were adopted to enhance gold recovery rates. These included (i) pretreatment of e-waste to remove competing metal ions, (ii) mutation to adapt the bacteria to high pH environment, (iii) metabolic engineering to produce higher cyanide lixiviant, and (iv) spent medium leaching with adjusted initial pH. Compared to 7.1 % recovery by the wild type bacteria, these strategies achieved gold recoveries of 11.3%, 22.5%, 30% and 30% respectively at 0.5% w/v pulp density respectively. Bioleached gold was finally mineralized and precipitated as gold nanoparticles using the bacterium Delftia acidovorans. This study demonstrates the potential for enhancement of biocyanide production and gold recovery from electronic waste through different strategies, and extraction of solid gold from bioleached leachate.

Hidden flows and waste processing--an analysis of illustrative futures.

Science.gov (United States)

Schiller, F; Raffield, T; Angus, A; Herben, M; Young, P J; Longhurst, P J; Pollard, S J T

2010-12-14

An existing materials flow model is adapted (using Excel and AMBER model platforms) to account for waste and hidden material flows within a domestic environment. Supported by national waste data, the implications of legislative change, domestic resource depletion and waste technology advances are explored. The revised methodology offers additional functionality for economic parameters that influence waste generation and disposal. We explore this accounting system under hypothetical future waste and resource management scenarios, illustrating the utility of the model. A sensitivity analysis confirms that imports, domestic extraction and their associated hidden flows impact mostly on waste generation. The model offers enhanced utility for policy and decision makers with regard to economic mass balance and strategic waste flows, and may promote further discussion about waste technology choice in the context of reducing carbon budgets.

Low-level radioactive wastes in subsurface soils

International Nuclear Information System (INIS)

Francis, A.J.

1985-01-01

Low-level radioactive wastes will continue to be buried in shallow-land waste disposal sites. Several of the burial sites have been closed because of the problems that developed as a result of poor site characteristics, types of waste buried, and a number of other environmental factors. Some of the problems encountered can be traced to the activities of microorganisms. These include microbial degradation of waste forms resulting in trench cover subsidence, production of radioactive gases, and production of microbial metabolites capable of complexation, solubilization, and bioaccumulation of radionuclides. Improvements in disposal technology are being developed to minimize these problems. These include waste segregation, waste pretreatment, incineration, and solidification. Microorganisms are also known to enhance and inhibit the movement of metals. Little is known about the role of autotrophic microbial transformations of radionuclides. Such microbial processes may be significant in light of improved disposal procedures, which may result in reductions in the organic content of the waste disposed of at shallow-land sites. 102 references, 5 figures, 19 tables

Uptake of heavy metals and As by Brassica juncea grown in a contaminated soil in Aznalcollar (Spain): The effect of soil amendments

Energy Technology Data Exchange (ETDEWEB)

Clemente, Rafael [Department of Soil and Water Conservation and Organic Waste Management. Centro de Edafologia y Biologia Aplicada del Segura, CSIC. Apartado 164, 30100 Espinardo, Murcia (Spain); Walker, David J. [Department of Soil and Water Conservation and Organic Waste Management. Centro de Edafologia y Biologia Aplicada del Segura, CSIC. Apartado 164, 30100 Espinardo, Murcia (Spain); Bernal, M. Pilar [Department of Soil and Water Conservation and Organic Waste Management. Centro de Edafologia y Biologia Aplicada del Segura, CSIC. Apartado 164, 30100 Espinardo, Murcia (Spain)]. E-mail: pbernal@cebas.csic.es

2005-11-15

Two crops of Brassica juncea (L.) Czern. were grown in a field experiment, at the site affected by the toxic spillage of acidic, metal-rich waste in Aznalcollar (Seville, Spain), to study its metal accumulation and the feasibility of its use for metal phytoextraction. The effects of organic soil amendments (cow manure and mature compost) and lime on biomass production and plant survival were also assessed; plots without organic amendment and without lime were used as controls. Plots, with or without organic amendment, having pH<5 were limed for the second crop. Soil acidification conditioned plant growth and metal accumulation. The addition of lime and the organic amendments achieved higher plant biomass production, although effects concerning metal bioavailability and accumulation were masked somewhat by pH variability with time and between and within plots. Tissue metal concentrations of B. juncea were elevated for Zn, Cu and Pb, especially in leaves of plants from plots with low pH values (maxima of 2029, 71 and 55 {mu}g g{sup -1}, respectively). The total uptake of heavy metals in the plants was relatively low, emphasising the problems faced when attempting to employ phytoextraction for clean-up of pluri-contaminated sites. - Although organic amendments improved soil conditions and plant growth, the phytoextraction capacity of Brassica juncea (cv. Z1) is too low for efficient soil remediation.

Mobilization of heavy metals from contaminated paddy soil by EDDS, EDTA, and elemental sulfur

NARCIS (Netherlands)

Wang, G.; Koopmans, G.F.; Song, J.; Temminghoff, E.J.M.; Luo, Y.; Zhao, Q.; Japenga, J.

2007-01-01

For enhanced phytoextraction, mobilization of heavy metals (HMs) from the soil solid phase to soil pore water is an important process. A pot incubation experiment mimicking field conditions was conducted to investigate the performance of three soil additives in mobilizing HMs from contaminated paddy

Central processing and interim storage of radioactive wastes

International Nuclear Information System (INIS)

Wenger, J.P.

1996-01-01

Within the ZWILAG project, the buildings for the temporary storage of all categories of radioactive wastes including the spent fuel elements are being readied at a central location. The intermediate storage installations are enhanced by a conditioning and burning plant for weak radioactive operating waste from the nuclear power plants and from the area of responsibility of the state. (author) 2 figs

Phytoextract of Indian mustard seeds acts by suppressing the generation of ROS against acetaminophen-induced hepatotoxicity in HepG2 cells.

Science.gov (United States)

Parikh, Harita; Pandita, Nancy; Khanna, Aparna

2015-07-01

Indian mustard [Brassica juncea (L.) Czern. & Coss. (Brassicaceae)] is reported to possess diverse pharmacological properties. However, limited information is available concerning its hepatoprotective activity and mechanism of action. To study the protective mechanism of mustard seed extract against acetaminophen (APAP) toxicity in a hepatocellular carcinoma (HepG2) cell line. Hepatotoxicity models were established using APAP (2.5-22.5 mM) based on the cytotoxicity profile. An antioxidant-rich fraction from mustard seeds was extracted and evaluated for its hepatoprotective potential. The mechanism of action was elucidated using various in vitro antioxidant assays, the detection of intracellular generation of reactive oxygen species (ROS), and cell cycle analysis. The phytoconstituents isolated via HPLC-DAD were also evaluated for hepatoprotective activity. Hydromethanolic seed extract exhibited hepatoprotective activity in post- and pre-treatment models of 20 mM APAP toxicity and restored the elevated levels of liver indices to normal values (p DAD analysis revealed the presence quercetin, vitamin E, and catechin, which exhibited hepatoprotective activity. A phytoextract of mustard seeds acts by suppressing the generation of ROS in response to APAP toxicity.

Instrumentation and methods evaluations for shallow land burial of waste materials: water erosion

International Nuclear Information System (INIS)

Hostetler, D.D.; Murphy, E.M.; Childs, S.W.

1981-08-01

The erosion of geologic materials by water at shallow-land hazardous waste disposal sites can compromise waste containment. Erosion of protective soil from these sites may enhance waste transport to the biosphere through water, air, and biologic pathways. The purpose of this study was to review current methods of evaluating soil erosion and to recommend methods for use at shallow-land, hazardous waste burial sites. The basic principles of erosion control are: minimize raindrop impact on the soil surface; minimize runoff quantity; minimize runoff velocity; and maximize the soil's resistance to erosion. Generally soil erosion can be controlled when these principles are successfully applied at waste disposal sites. However, these erosion control practices may jeopardize waste containment. Typical erosion control practices may enhance waste transport by increasing subsurface moisture movement and biologic uptake of hazardous wastes. A two part monitoring program is recommended for US Department of Energy (DOE) hazardous waste disposal sites. The monitoring programs and associated measurement methods are designed to provide baseline data permitting analysis and prediction of long term erosion hazards at disposal sites. These two monitoring programs are: (1) site reconnaissance and tracking; and (2) site instrumentation. Some potential waste transport problems arising from erosion control practices are identified. This report summarizes current literature regarding water erosion prediction and control

Agro fertilizer from Myanmar traditional shrimp sauce and paste waste

International Nuclear Information System (INIS)

Yee Yee Nwe; Myint Khine; Nyunt Wynn

2001-01-01

The new growth agro fertilizer (npi) compost prepared from Myanmar traditional shrimp sauce and paste waste mixed with other ingredients [agricultural waste and animal waste (night soil)] was found to promote and enhance the growth as well as the rice crop to produce in higher percentage yield per acre as compare to the use of normal rice crops fertilizer and even to that of the current used EM compost fertilizer. (author)

Evaluation of Redox Conditions and Enhanced Arsenic Mobility from Waste Disposal in a Complex Fractured Crystalline-Rock Aquifer, Raymond, New Hampshire, USA (Note: article rewritten under new title)

Science.gov (United States)

(Note: This entry is no longer valid; the paper was rewritten and submitted to a different journal.) This paper highlights some methods that can be used at a local scale to assess whether waste disposal activities are responsible for enhanced arsenic mobility through redox-contro...

210Pb and 210Po in sediments and suspended matter in the Tagus estuary, Portugal: Local enhancement of natural levels by wastes from phosphate ore processing industry

International Nuclear Information System (INIS)

Carvalho, Fernando P.

1994-01-01

Results of analyses of uranium series radionuclides in phosphate ore and in wastes released by the phosphate fertilizer industry confirm their potential for the enhancement of environmental radioactivity levels. Therefore, concentrations of 210 Pb and 210 Po were measured in bottom sediments and suspended matter in the Tagus estuary, Portugal, to assess the enhancement of radioactivity due to wastes from the phosphate industry. The concentration of 210 Pb in surface sediments in the estuary increased inversely with sediment grain-size; conversely, increased percentage of sand has a dilution effect on the concentration of 210 Pb measured in bulk sediment samples. By normalizing the data to the 210 Pb in sediments was found to be 68 ± 19 Bq kg -1 (dry wt.) in background sediments. Higher 210 Pb levels, up to 1580 Bq kg -1 (dry wt.), were measured in some bulk sediment samples. It was verified that this radionuclide has been introduced by the discharge of wastes from a phosphate fertilizer plant but enhanced concentrations are localized near the point of discharge. In other zones of the estuary, the concentrations of 210 Pb in sediments and suspended matter were generally below those measured in the zone of phosphatic releases at the Barreiro Peninsula. Concentrations higher than the predicted average concentration of unsupported 210 Pb from natural sources (atmospheric deposition, river input) were also measured in the upper estuary, both in bottom sediments and in suspended matter. It is suggested that these relatively elevated concentrations are due to the highly efficient scavenging of soluble naturally-occurring unsupported 210 Pb onto suspended matter and to co-precipitation with iron-manganese hydroxides in the fresh water-salt water mixing zone

The effect of plant growth-promoting rhizobacteria on the phytoextraction of Cd and Zn by Brassica napus L.

Science.gov (United States)

Dąbrowska, G; Hrynkiewicz, K; Trejgell, A; Baum, C

2017-07-03

The test strains Bacteroidetes bacterium (Ba), Pseudomonas fluorescens (Pf) and Variovorax sp. (Va) were selected in advance for their in vitro capability for growth promotion of rapeseed in the presence of increased concentrations of Cd, Cu, Pb and Zn in the medium. In the pot experiment, the strains were used for single Ba, Pf, Va or combined Ba + Pf, Ba + Va, Pf + Va, and Ba + Pf + Va inoculation of B. napus growing in contaminated soil from alluvial deposits. The positive effect of bacterial strains on plant growth was observed in vitro, but was not confirmed in situ in the contaminated soil, where the tested strains inhibited biomass production, rather than stimulating it. However, single inoculation with Ba significantly increased the chlorophyll content and K + concentration in the leaves. The inoculation of rapeseed with Ba and Va strains was indicated to be the most promising combination for phytoextraction of Cd and Zn from contaminated soil. Combined inoculation with Pf+Va and Pf + Ba+Va significantly decreased the concentration of heavy metals in the roots of rapeseed. We conclude that suitable combinations of PGPR can control the metal uptake of B. napus, selectively increasing either metal extraction or metal stabilization in the rhizosphere and offering promising applications in soil remediation.

An expert system framework for nondestructive waste assay

International Nuclear Information System (INIS)

Becker, G.K.

1996-01-01

Management and disposition of transuranic (RU) waste forms necessitates determining entrained RU and associated radioactive material quantities as per National RU Waste Characterization Program requirements. Technical justification and demonstration of a given NDA method used to determine RU mass and uncertainty in accordance with program quality assurance is difficult for many waste forms. Difficulties are typically founded in waste NDA methods that employ standards compensation and/or employment of simplifying assumptions on waste form configurations. Capability to determine and justify RU mass and mass uncertainty can be enhanced through integration of waste container data/information using expert system and empirical data-driven techniques with conventional data acquisition and analysis. Presented is a preliminary expert system framework that integrates the waste form data base, alogrithmic techniques, statistical analyses, expert domain knowledge bases, and empirical artificial intelligence modules into a cohesive system. The framework design and bases in addition to module development activities are discussed

High-level waste management technology program plan

Energy Technology Data Exchange (ETDEWEB)

Harmon, H.D.

1995-01-01

The purpose of this plan is to document the integrated technology program plan for the Savannah River Site (SRS) High-Level Waste (HLW) Management System. The mission of the SRS HLW System is to receive and store SRS high-level wastes in a see and environmentally sound, and to convert these wastes into forms suitable for final disposal. These final disposal forms are borosilicate glass to be sent to the Federal Repository, Saltstone grout to be disposed of on site, and treated waste water to be released to the environment via a permitted outfall. Thus, the technology development activities described herein are those activities required to enable successful accomplishment of this mission. The technology program is based on specific needs of the SRS HLW System and organized following the systems engineering level 3 functions. Technology needs for each level 3 function are listed as reference, enhancements, and alternatives. Finally, FY-95 funding, deliverables, and schedules are s in Chapter IV with details on the specific tasks that are funded in FY-95 provided in Appendix A. The information in this report represents the vision of activities as defined at the beginning of the fiscal year. Depending on emergent issues, funding changes, and other factors, programs and milestones may be adjusted during the fiscal year. The FY-95 SRS HLW technology program strongly emphasizes startup support for the Defense Waste Processing Facility and In-Tank Precipitation. Closure of technical issues associated with these operations has been given highest priority. Consequently, efforts on longer term enhancements and alternatives are receiving minimal funding. However, High-Level Waste Management is committed to participation in the national Radioactive Waste Tank Remediation Technology Focus Area. 4 refs., 5 figs., 9 tabs.

High-level waste management technology program plan

International Nuclear Information System (INIS)

Harmon, H.D.

1995-01-01

The purpose of this plan is to document the integrated technology program plan for the Savannah River Site (SRS) High-Level Waste (HLW) Management System. The mission of the SRS HLW System is to receive and store SRS high-level wastes in a see and environmentally sound, and to convert these wastes into forms suitable for final disposal. These final disposal forms are borosilicate glass to be sent to the Federal Repository, Saltstone grout to be disposed of on site, and treated waste water to be released to the environment via a permitted outfall. Thus, the technology development activities described herein are those activities required to enable successful accomplishment of this mission. The technology program is based on specific needs of the SRS HLW System and organized following the systems engineering level 3 functions. Technology needs for each level 3 function are listed as reference, enhancements, and alternatives. Finally, FY-95 funding, deliverables, and schedules are s in Chapter IV with details on the specific tasks that are funded in FY-95 provided in Appendix A. The information in this report represents the vision of activities as defined at the beginning of the fiscal year. Depending on emergent issues, funding changes, and other factors, programs and milestones may be adjusted during the fiscal year. The FY-95 SRS HLW technology program strongly emphasizes startup support for the Defense Waste Processing Facility and In-Tank Precipitation. Closure of technical issues associated with these operations has been given highest priority. Consequently, efforts on longer term enhancements and alternatives are receiving minimal funding. However, High-Level Waste Management is committed to participation in the national Radioactive Waste Tank Remediation Technology Focus Area. 4 refs., 5 figs., 9 tabs

Degradation of dome cutting minerals in Hanford waste-13100

International Nuclear Information System (INIS)

Reynolds, Jacob G.; Huber, Heinz J.; Cooke, Gary A.

2013-01-01

At the Hanford Tank Farms, recent changes in retrieval technology require cutting new risers in several single-shell tanks. The Hanford Tank Farm Operator is using water jet technology with abrasive silicate minerals such as garnet or olivine to cut through the concrete and rebar dome. The abrasiveness of these minerals, which become part of the high-level waste stream, may enhance the erosion of waste processing equipment. However, garnet and olivine are not thermodynamically stable in Hanford waste, slowly degrading over time. How likely these materials are to dissolve completely in the waste before the waste is processed in the Waste Treatment and Immobilization Plant can be evaluated using theoretical analysis for olivine and collected direct experimental evidence for garnet. Based on an extensive literature study, a large number of primary silicates decompose into sodalite and cancrinite when exposed to Hanford waste. Given sufficient time, the sodalite also degrades into cancrinite. Even though cancrinite has not been directly added to any Hanford tanks during process times, it is the most common silicate observed in current Hanford waste. By analogy, olivine and garnet are expected to ultimately also decompose into cancrinite. Garnet used in a concrete cutting demonstration was immersed in a simulated supernate representing the estimated composition of the liquid retrieving waste from Hanford tank 241-C-107 at both ambient and elevated temperatures. This simulant was amended with extra NaOH to determine if adding caustic would help enhance the degradation rate of garnet. The results showed that the garnet degradation rate was highest at the highest NaOH concentration and temperature. At the end of 12 weeks, however, the garnet grains were mostly intact, even when immersed in 2 molar NaOH at 80 deg C. Cancrinite was identified as the degradation product on the surface of the garnet grains. In the case of olivine, the rate of degradation in the high-pH regimes