Eco-efficient post treatment of digestate from farm and collective biogas plants to improve nutrients (N&P) recycling

DEFF Research Database (Denmark)

Trémier, Anne; Béline, Fabrice; Déchaux, Claire

an opportunity to improve nutrient recycling from organic waste through the development of an eco-effi cient post-treatment system. In this context, LCA was applied to evaluate the sustainability of diff erent raw digestate post-treatment technologies regarding recycling of nutrients from agricultural...... and organic waste to agricultural soils for decreased resource depletion and climate mitigation. Substitution of the use of N and P mineral fertilizers with recycled soil health improver or organic fertilizers products as function of fi ve diff erent post-treatment technologies and raw digestate...... characteristics was evaluated. A particular attention was carried to (1) the gaseous emissions (NH3 and N2O) from process (post-treatment) but also after land spreading and (2) the carbon cycle considering the CO2 carbon costs of fertiliser production and the soil carbon sequestration benefit....

A methodology to quantify the aerobic and anaerobic sludge digestion performance for nutrient recycling in aquaponics

Directory of Open Access Journals (Sweden)

Delaide, B.

2018-01-01

Full Text Available Description of the subject. This research note presents a methodology to quantify the tilapia sludge digestion performance in aerobic and anaerobic reactors for aquaponic purpose. Both organic reduction and macro- and microelements mineralization performances were addressed. Objectives. To set up an appropriate methodology to quantify sludge digestion performance in aquaponics. To describe the methodology and illustrate it with some results as example. Method. Equations were adapted to quantify (1 the organic reduction performance in terms of chemical oxygen demand (COD and total suspended solids (TSS reduction, and (2 the nutrient recycling performance in terms of macro- and microelements mineralization. Results. The equations were applied to data obtained from experimental aerobic and anaerobic reactors as example. Reactors were able to remove at least 50% of the TSS and COD input. The nutrient mineralization was consistent with a 10 — 60% range for all macro- and micronutrients. Conclusions. The methodology provides explicit indicators on the sludge treatment performances for aquaponics. Treating aquaponic sludge onsite is promising to avoid sludge spillage, improve nutrient recycling and save water.

Potential GTCC LLW sealed radiation source recycle initiatives

International Nuclear Information System (INIS)

Fischer, D.

1992-04-01

This report suggests 11 actions that have the potential to facilitate the recycling (reuse or radionuclide) of surplus commercial sealed radiation sources that would otherwise be disposed of as greater-than-Class C low-level radioactive waste. The suggestions serve as a basis for further investigation and discussion between the Department of Energy, Nuclear Regulatory Commission, Agreement States, and the commercial sector. Information is also given that describes sealed sources, how they are used, and problems associated with recycling, including legal concerns. To illustrate the nationwide recycling potential, Appendix A gives the estimated quantity and application information for sealed sources that would qualify for disposal in commercial facilities if not recycle. The report recommends that the Department of Energy initiate the organization of a forum to explore the suggested actions and other recycling possibilities

Recycling of lipid-extracted hydrolysate as nitrogen supplementation for production of thraustochytrid biomass.

Science.gov (United States)

Lowrey, Joshua; Armenta, Roberto E; Brooks, Marianne S

2016-08-01

Efficient resource usage is important for cost-effective microalgae production, where the incorporation of waste streams and recycled water into the process has great potential. This study builds upon emerging research on nutrient recycling in thraustochytrid production, where waste streams are recovered after lipid extraction and recycled into future cultures. This research investigates the nitrogen flux of recycled hydrolysate derived from enzymatic lipid extraction of thraustochytrid biomass. Results indicated the proteinaceous content of the recycled hydrolysate can offset the need to supply fresh nitrogen in a secondary culture, without detrimental impact upon the produced biomass. The treatment employing the recycled hydrolysate with no nitrogen addition accumulated 14.86 g L(-1) of biomass in 141 h with 43.3 % (w/w) lipid content compared to the control which had 9.26 g L(-1) and 46.9 % (w/w), respectively. This improved nutrient efficiency and wastewater recovery represents considerable potential for enhanced resource efficiency of commercial thraustochytrid production.

Hydrothermal upgrading of algae paste: Inorganics and recycling potential in the aqueous phase

Energy Technology Data Exchange (ETDEWEB)

Patel, Bhavish; Guo, Miao; Chong, Chinglih; Sarudin, Syazwani Hj Mat; Hellgardt, Klaus, E-mail: k.hellgardt@imperial.ac.uk

2016-10-15

Hydrothermal Liquefaction (HTL) for algal biomass conversion is a promising technology capable of producing high yields of biocrude as well as partitioning even higher quantity of nutrients in the aqueous phase. To assess the feasibility of utilizing the aqueous phase, HTL of Nannochloropsis sp. was carried out in the temperature range of 275 to 350 °C and Residence Times (RT) ranging between 5 and 60 min The effect of reaction conditions on the NO{sub 3}{sup −} , PO{sub 4}{sup 3} {sup −}, SO{sub 4}{sup 2} {sup −}, Cl{sup −}, Na{sup +}, and K{sup +} ions as well as Chemical Oxygen Demand (COD) and pH was investigated with view of recycling the aqueous phase for either cultivation or energy generation via Anaerobic Digestion (AD), quantified via Lifecycle Assessment (LCA). It addition to substantial nutrient partitioning at short RT, an increase in alkalinity to almost pH 10 and decrease in COD at longer RT was observed. The LCA investigation found reaction conditions of 275 °C/30 min and 350 °C/10 min to be most suitable for nutrient and energy recovery but both processing routes offer environmental benefit at all reaction conditions, however recycling for cultivation has marginally better environmental credentials compared to AD. - Highlights: • HTL of algal biomass and nutrient reclamation • Microalgae HTL aqueous phase inorganics analysis • Recycle/re-use of aqueous phase for energy or cultivation • Substantial environmental benefit from HTL of aqueous phase • Reuse for cultivation more beneficial than Anaerobic Digestion.

Imbalanced nutrient recycling in a warmer ocean driven by differential response of extracellular enzymatic activities

KAUST Repository

Ayo, Begoñ a; Abad, Naiara; Artolozaga, Itxaso; Azua, Iñ igo; Bañ a, Zuriñ e; Unanue, Marian; Gasol, Josep M.; Duarte, Carlos M.; Iriberri, Juan

2017-01-01

Ocean oligotrophication concurrent with warming weakens the capacity of marine primary producers to support marine food webs and act as a CO2 sink, and is believed to result from reduced nutrient inputs associated to the stabilization of the thermocline. However, nutrient supply in the oligotrophic ocean is largely dependent on the recycling of organic matter. This involves hydrolytic processes catalyzed by extracellular enzymes released by bacteria, which temperature-dependence has not yet been evaluated. Here we report a global assessment of the temperature-sensitivity, as represented by the activation energies (Ea ), of extracellular β-glucosidase (βG), leucine aminopeptidase (LAP) and alkaline phosphatase (AP) enzymatic activities, which enable the uptake by bacteria of substrates rich in carbon, nitrogen and phosphorus, respectively. These Ea were calculated from two different approaches, temperature experimental manipulations and a space-for-time substitution approach, which generated congruent results. The three activities showed contrasting Ea in the subtropical and tropical ocean, with βG increasing the fastest with warming, followed by LAP, while AP showed the smallest increase. The estimated activation energies predict that the hydrolysis products under projected warming scenarios will have higher C:N, C:P and N:P molar ratios than those currently generated, and suggest that the warming of oceanic surface waters leads to a decline in the nutrient supply to the microbial heterotrophic community relative to that of carbon, particularly so for phosphorus, slowing down nutrient recycling and contributing to further ocean oligotrophication. This article is protected by copyright. All rights reserved.

Imbalanced nutrient recycling in a warmer ocean driven by differential response of extracellular enzymatic activities

KAUST Repository

Ayo, Begoña

2017-06-08

Ocean oligotrophication concurrent with warming weakens the capacity of marine primary producers to support marine food webs and act as a CO2 sink, and is believed to result from reduced nutrient inputs associated to the stabilization of the thermocline. However, nutrient supply in the oligotrophic ocean is largely dependent on the recycling of organic matter. This involves hydrolytic processes catalyzed by extracellular enzymes released by bacteria, which temperature-dependence has not yet been evaluated. Here we report a global assessment of the temperature-sensitivity, as represented by the activation energies (Ea ), of extracellular β-glucosidase (βG), leucine aminopeptidase (LAP) and alkaline phosphatase (AP) enzymatic activities, which enable the uptake by bacteria of substrates rich in carbon, nitrogen and phosphorus, respectively. These Ea were calculated from two different approaches, temperature experimental manipulations and a space-for-time substitution approach, which generated congruent results. The three activities showed contrasting Ea in the subtropical and tropical ocean, with βG increasing the fastest with warming, followed by LAP, while AP showed the smallest increase. The estimated activation energies predict that the hydrolysis products under projected warming scenarios will have higher C:N, C:P and N:P molar ratios than those currently generated, and suggest that the warming of oceanic surface waters leads to a decline in the nutrient supply to the microbial heterotrophic community relative to that of carbon, particularly so for phosphorus, slowing down nutrient recycling and contributing to further ocean oligotrophication. This article is protected by copyright. All rights reserved.

Imbalanced nutrient recycling in a warmer ocean driven by differential response of extracellular enzymatic activities.

Science.gov (United States)

Ayo, Begoña; Abad, Naiara; Artolozaga, Itxaso; Azua, Iñigo; Baña, Zuriñe; Unanue, Marian; Gasol, Josep M; Duarte, Carlos M; Iriberri, Juan

2017-10-01

Ocean oligotrophication concurrent with warming weakens the capacity of marine primary producers to support marine food webs and act as a CO 2 sink, and is believed to result from reduced nutrient inputs associated to the stabilization of the thermocline. However, nutrient supply in the oligotrophic ocean is largely dependent on the recycling of organic matter. This involves hydrolytic processes catalyzed by extracellular enzymes released by bacteria, which temperature dependence has not yet been evaluated. Here, we report a global assessment of the temperature-sensitivity, as represented by the activation energies (E a ), of extracellular β-glucosidase (βG), leucine aminopeptidase (LAP) and alkaline phosphatase (AP) enzymatic activities, which enable the uptake by bacteria of substrates rich in carbon, nitrogen, and phosphorus, respectively. These E a were calculated from two different approaches, temperature experimental manipulations and a space-for-time substitution approach, which generated congruent results. The three activities showed contrasting E a in the subtropical and tropical ocean, with βG increasing the fastest with warming, followed by LAP, while AP showed the smallest increase. The estimated activation energies predict that the hydrolysis products under projected warming scenarios will have higher C:N, C:P and N:P molar ratios than those currently generated, and suggest that the warming of oceanic surface waters leads to a decline in the nutrient supply to the microbial heterotrophic community relative to that of carbon, particularly so for phosphorus, slowing down nutrient recycling and contributing to further ocean oligotrophication. © 2017 John Wiley & Sons Ltd.

Nutrient capture and recycling by periphyton attached to modified agrowaste carriers.

Science.gov (United States)

Wan, Juanjuan; Liu, Xuemei; Wu, Chenxi; Wu, Yonghong

2016-04-01

The reuse of periphytic biofilm from traditional wastewater treatment (i.e., active sludge process) is inefficient to recycle nutrients due to low accumulation of nutrients. Then, in this study, peanut shell (PS), rice husk (RH), decomposed peanut shell (DPS), acidified rice husks (ARH), and a commonly used carrier-ceramsite (C, as the control)-were used to support the growth of periphyton. Results showed that DPS and ARH supported significantly higher periphyton biomass and metabolic versatility than PS and RH, respectively, due to the increased presence of positive groups. The total nitrogen (TN) and total phosphorus (TP) captured by periphyton were enhanced by 600-657 and 833-3255 % for DPS, and 461-1808 and 21-308 % for ARH, respectively. The removal of nutrients from simulated eutrophic surface waters using periphyton attached to DPS was improved by 24-47 % for TP, 12-048 % for TN, and 15-78 % for nitrate compared to the control. The results indicate that the periphyton attached to modified agrowaste was capable of efficiently entrapping and storing N and P from eutrophic water. This study also implies that the mixture of periphyton and the modified agrowaste carriers are promising raw materials of biofertilizer.

Assessment of Food Waste Prevention and Recycling Strategies Using a Multilayer Systems Approach.

Science.gov (United States)

Hamilton, Helen A; Peverill, M Samantha; Müller, Daniel B; Brattebø, Helge

2015-12-15

Food waste (FW) generates large upstream and downstream emissions to the environment and unnecessarily consumes natural resources, potentially affecting future food security. The ecological impacts of FW can be addressed by the upstream strategies of FW prevention or by downstream strategies of FW recycling, including energy and nutrient recovery. While FW recycling is often prioritized in practice, the ecological implications of the two strategies remain poorly understood from a quantitative systems perspective. Here, we develop a multilayer systems framework and scenarios to quantify the implications of food waste strategies on national biomass, energy, and phosphorus (P) cycles, using Norway as a case study. We found that (i) avoidable food waste in Norway accounts for 17% of sold food; (ii) 10% of the avoidable food waste occurs at the consumption stage, while industry and retailers account for only 7%; (iii) the theoretical potential for systems-wide net process energy savings is 16% for FW prevention and 8% for FW recycling; (iv) the theoretical potential for systems-wide P savings is 21% for FW prevention and 9% for FW recycling; (v) while FW recycling results in exclusively domestic nutrient and energy savings, FW prevention leads to domestic and international savings due to large food imports; (vi) most effective is a combination of prevention and recycling, however, FW prevention reduces the potential for FW recycling and therefore needs to be prioritized to avoid potential overcapacities for FW recycling.

Pyrolysis and co-composting of municipal organic waste in Bangladesh: A quantitative estimate of recyclable nutrients, greenhouse gas emissions, and economic benefits.

Science.gov (United States)

Mia, Shamim; Uddin, Md Ektear; Kader, Md Abdul; Ahsan, Amimul; Mannan, M A; Hossain, Mohammad Monjur; Solaiman, Zakaria M

2018-05-01

Waste causes environmental pollution and greenhouse gas (GHG) emissions when it is not managed sustainably. In Bangladesh, municipal organic waste (MOW) is partially collected and landfilled. Thus, it causes deterioration of the environment urging a recycle-oriented waste management system. In this study, we propose a waste management system through pyrolysis of selective MOW for biochar production and composting of the remainder with biochar as an additive. We estimated the carbon (C), nitrogen (N), phosphorus (P) and potassium (K) recycling potentials in the new techniques of waste management. Waste generation of a city was calculated using population density and per capita waste generation rate (PWGR). Two indicators of economic development, i.e., gross domestic product (GDP) and per capita gross national income (GNI) were used to adopt PWGR with a projected contribution of 5-20% to waste generation. The projected PWGR was then validated with a survey. The waste generation from urban areas of Bangladesh in 2016 was estimated between 15,507 and 15,888 t day -1 with a large share (∼75%) of organic waste. Adoption of the proposed system could produce 3936 t day -1 biochar blended compost with an annual return of US $210 million in 2016 while it could reduce GHG emission substantially (-503 CO 2 e t -1 municipal waste). Moreover, the proposed system would able to recover ∼46%, 54%, 54% and 61% of total C, N, P and K content in the initial waste, respectively. We also provide a projection of waste generation and nutrient recycling potentials for the year 2035. The proposed method could be a self-sustaining policy option for waste management as it would generate ∼US$51 from each tonne of waste. Moreover, a significant amount of nutrients can be recycled to agriculture while contributing to the reduction in environmental pollution and GHG emission. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cell phone recycling experiences in the United States and potential recycling options in Brazil.

Science.gov (United States)

Silveira, Geraldo T R; Chang, Shoou-Yuh

2010-11-01

This paper presents an overview of cell phone recycling programs currently available in the United States. At the same time, it also provides analyses of the current recycling situation and possible recycling alternatives for Brazil. Although there are several recycling options in the United States, collection rates are still only 10% of all potential devices because customers are not aware of these possibilities. The whole system is financially based on reselling refurbished cell phones and recycled materials to developing countries which represent an effective and strong market. Several recyclers offer funds to collection partners who are either charities or who work with charities while obtaining the materials that they need in order to run their operations. A mobile phone recycling system for Brazil considering the United States experience and the Extended Producer Responsibility (EPR) principle is suggested. A deposit/refund/advance-recycling fee is proposed which might be implemented as a voluntary industrial initiative managed by PRO Brazil, a producer responsibility organization. One widespread public-private agreement will integrate all mobile phone stakeholders, and environmental education actions and promotional events will promote citizen's participation. Copyright © 2010 Elsevier Ltd. All rights reserved.

Recycle of Inorganic Nutrients for Hydroponic Crop Production Following Incineration of Inedible Biomass

Science.gov (United States)

Bubenheim, David L.; Wignarajah, Kanapathipillai; Kliss, Mark H. (Technical Monitor)

1996-01-01

but matching the quality of the ash only treatment resulted in growth similar to that of the ash only treatment. The ash product resulting from incineration of inedible biomass appears to be a suitable form for recycle of inorganic nutrients to crop production.

Solid waste characterization and recycling potential for a university campus

International Nuclear Information System (INIS)

Armijo de Vega, Carolina; Ojeda Benitez, Sara; Ramirez Barreto, Ma. Elizabeth

2008-01-01

Integrated waste management systems are one of the greatest challenges for sustainable development. For these systems to be successful, the first step is to carry out waste characterization studies. In this paper are reported the results of a waste characterization study performed in the Campus Mexicali I of the Autonomous University of Baja California (UABC). The aim of this study was to set the basis for implementation of a recovery, reduction and recycling waste management program at the campus. It was found that the campus Mexicali I produces 1 ton of solid wastes per day; more than 65% of these wastes are recyclable or potentially recyclable. These results showed that a program for segregation and recycling is feasible on a University Campus. The study also showed that the local market for recyclable waste, under present conditions - number of recycling companies and amounts of recyclables accepted - can absorb all of these wastes. Some alternatives for the potentially recyclables wastes are discussed. Finally some strategies that could be used to reduce waste at the source are discussed as well

Recycling potential of neodymium: the case of computer hard disk drives.

Science.gov (United States)

Sprecher, Benjamin; Kleijn, Rene; Kramer, Gert Jan

2014-08-19

Neodymium, one of the more critically scarce rare earth metals, is often used in sustainable technologies. In this study, we investigate the potential contribution of neodymium recycling to reducing scarcity in supply, with a case study on computer hard disk drives (HDDs). We first review the literature on neodymium production and recycling potential. From this review, we find that recycling of computer HDDs is currently the most feasible pathway toward large-scale recycling of neodymium, even though HDDs do not represent the largest application of neodymium. We then use a combination of dynamic modeling and empirical experiments to conclude that within the application of NdFeB magnets for HDDs, the potential for loop-closing is significant: up to 57% in 2017. However, compared to the total NdFeB production capacity, the recovery potential from HDDs is relatively small (in the 1-3% range). The distributed nature of neodymium poses a significant challenge for recycling of neodymium.

Prospects for methane production and nutrient recycling from lipid extracted residues and whole Nannochloropsis salina using anaerobic digestion

International Nuclear Information System (INIS)

Bohutskyi, Pavlo; Chow, Steven; Ketter, Ben; Betenbaugh, Michael J.; Bouwer, Edward J.

2015-01-01

Highlights: • Semi-continuous AD of untreated and enzymatically pretreated lipid extracted algae. • Coupled biodiesel and methane process yields 40% more energy than biodiesel alone. • Thermal pretreatment (150–170 °C) of whole algae was more effective than enzymatic. • Addition of 5% of AD effluent was optimal to support high growth of Nannochloropsis. • AD effluent can partly replace chemical fertilizer for algal growth. - Abstract: Sustainable mass production of algal biofuels requires a reduction in nutrient demand and efficient conversion into fuels of all biomass including lipid-extracted algal residues (LEA). This study evaluated methane production, nutrient recovery and recycling from untreated and enzymatically pretreated Nannochloropsis LEA using semi-continuous anaerobic digestion (AD). Additionally, this process was compared to methane generation from whole Nannochloropsis alga (WA) and thermally pretreated WA. The methane production from untreated LEA and WA reached up to 0.22 L and 0.24 L per gram of biomass volatile solids (VS), respectively, corresponding to only 36–38% of the theoretical potential. Additionally, observed VS reduction was only 40–50% confirming biomass recalcitrance to biodegradation. While enzymatic treatment hydrolyzed up to 65% of the LEA polysaccharides, the methane production increased by only 15%. Alternatively, WA thermal pretreatment at 150–170 °C enhanced methane production up to 40%. Overall, an integrated process of lipid conversion into biodiesel coupled with LEA conversion into methane generates nearly 40% more energy compared to methane production from WA, and about 100% more energy than from biodiesel alone. Additionally, the AD effluent contained up to 60–70% of the LEA phosphorus content, 30–50% of the nitrogen, sulfur, calcium and boron, 20% of the iron and cobalt, and 10% of manganese, zinc and copper, which can partially replace chemical fertilizers during algal cultivation. Consequently

Micro-halocline enabled nutrient recycling may explain extreme Azolla event in the Eocene Arctic Ocean.

Science.gov (United States)

van Kempen, Monique M L; Smolders, Alfons J P; Lamers, Leon P M; Roelofs, Jan G M

2012-01-01

In order to understand the physicochemical mechanisms that could explain the massive growth of Azolla arctica in the Eocene Arctic Ocean, we carried out a laboratory experiment in which we studied the interacting effects of rain and wind on the development of salinity stratification, both in the presence and in the absence of a dense Azolla cover. Additionally, we carried out a mesocosm experiment to get a better understanding of the nutrient cycling within and beneath a dense Azolla cover in both freshwater and brackish water environments. Here we show that Azolla is able to create a windproof, small-scale salinity gradient in brackish waters, which allows for efficient recycling of nutrients. We suggest that this mechanism ensures the maintenance of a large standing biomass in which additional input of nutrients ultimately result in a further expansion of an Azolla cover. As such, it may not only explain the extent of the Azolla event during the Eocene, but also the absence of intact vegetative Azolla remains and the relatively low burial efficiency of organic carbon during this interval.

Micro-halocline enabled nutrient recycling may explain extreme Azolla event in the Eocene Arctic Ocean.

Directory of Open Access Journals (Sweden)

Monique M L van Kempen

Full Text Available In order to understand the physicochemical mechanisms that could explain the massive growth of Azolla arctica in the Eocene Arctic Ocean, we carried out a laboratory experiment in which we studied the interacting effects of rain and wind on the development of salinity stratification, both in the presence and in the absence of a dense Azolla cover. Additionally, we carried out a mesocosm experiment to get a better understanding of the nutrient cycling within and beneath a dense Azolla cover in both freshwater and brackish water environments. Here we show that Azolla is able to create a windproof, small-scale salinity gradient in brackish waters, which allows for efficient recycling of nutrients. We suggest that this mechanism ensures the maintenance of a large standing biomass in which additional input of nutrients ultimately result in a further expansion of an Azolla cover. As such, it may not only explain the extent of the Azolla event during the Eocene, but also the absence of intact vegetative Azolla remains and the relatively low burial efficiency of organic carbon during this interval.

Unravelling trophic subsidies of agroecosystems for biodiversity conservation: Food consumption and nutrient recycling by waterbirds in Mediterranean rice fields

International Nuclear Information System (INIS)

Navedo, Juan G.; Hahn, Steffen; Parejo, Manuel; Abad-Gómez, José M.; Gutiérrez, Jorge S.; Villegas, Auxiliadora; Sánchez-Guzmán, Juan M.; Masero, José A.

2015-01-01

Waterbirds can reallocate a considerable amount of nutrients within agricultural fields and between agriculture sites and wetlands. However their effects on biogeochemical cycles have rarely been quantified. We estimated bird numbers, diet (from stable isotope analysis), food supply, and the food consumption on rice fields by overwintering waterbirds in one of the most important areas for rice production in southwestern Europe and a key area for various migrating and resident waterbird species. Herein, we modelled the nutrient (N and P) recycling in rice fields, and their transport to reservoirs. The energy consumption by waterbirds (96,605 ± 18,311 individuals) on rice fields during winter averaged at 89.9 ± 39.0 kJ·m −2 , with its majority (89.9%) belonging to foraging on rice seeds. Thus, the birds removed about 26% of rice seeds leftover after harvest (estimated in 932.5 ± 504.7 seeds·m −2 in early winter) wherein common cranes and dabbling ducks (four species) were the most important consumers. Waterbirds foraging and roosting in the rice fields recycled more than 24.1 (1.0 kg·ha −1 ) of N and an additional 5.0 tons (0.2 kg·ha −1 ) of P in the Extremadura's rice fields during winter. Additionally, we estimated that 2.3 tons of N and 550 kg of P were removed from rice fields and transported to reservoirs. The seasonal foraging of wildlife should result in a direct benefit for rice farmers by improving nutrient recycling through defecation by waterbirds with respect to artificial fertilisation. Additionally, rice fields located in the cranes' core wintering areas can provide sufficient food supply to induce habitat shift from their traditional wintering habitat in ‘dehesas’ to rice fields, which causes indirect socioeconomic benefit through reduced acorn consumption by cranes. Our modelling approach may thus be especially helpful for management decisions regarding rice agroecosystems in areas which are also important for the

Unravelling trophic subsidies of agroecosystems for biodiversity conservation: Food consumption and nutrient recycling by waterbirds in Mediterranean rice fields

Energy Technology Data Exchange (ETDEWEB)

Navedo, Juan G., E-mail: jgnavedo@uach.cl [Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Facultad de Ciencias, Campus Isla Teja, 5090000 Valdivia (Chile); Conservation Biology Research Group, Universidad de Extremadura, Avda. Elvas s/n, 06002 Badajoz (Spain); Hahn, Steffen [Department Bird Migration, Swiss Ornithological Institute, Seerose 1, 6204 Sempach (Switzerland); Parejo, Manuel; Abad-Gómez, José M. [Conservation Biology Research Group, Universidad de Extremadura, Avda. Elvas s/n, 06002 Badajoz (Spain); Gutiérrez, Jorge S. [Conservation Biology Research Group, Universidad de Extremadura, Avda. Elvas s/n, 06002 Badajoz (Spain); Department of Marine Ecology, Royal Netherlands Institute for Sea Research (NIOZ), PO Box 59, 1790 AB Den Burg, Texel (Netherlands); Villegas, Auxiliadora; Sánchez-Guzmán, Juan M.; Masero, José A. [Conservation Biology Research Group, Universidad de Extremadura, Avda. Elvas s/n, 06002 Badajoz (Spain)

2015-04-01

Waterbirds can reallocate a considerable amount of nutrients within agricultural fields and between agriculture sites and wetlands. However their effects on biogeochemical cycles have rarely been quantified. We estimated bird numbers, diet (from stable isotope analysis), food supply, and the food consumption on rice fields by overwintering waterbirds in one of the most important areas for rice production in southwestern Europe and a key area for various migrating and resident waterbird species. Herein, we modelled the nutrient (N and P) recycling in rice fields, and their transport to reservoirs. The energy consumption by waterbirds (96,605 ± 18,311 individuals) on rice fields during winter averaged at 89.9 ± 39.0 kJ·m{sup −2}, with its majority (89.9%) belonging to foraging on rice seeds. Thus, the birds removed about 26% of rice seeds leftover after harvest (estimated in 932.5 ± 504.7 seeds·m{sup −2} in early winter) wherein common cranes and dabbling ducks (four species) were the most important consumers. Waterbirds foraging and roosting in the rice fields recycled more than 24.1 (1.0 kg·ha{sup −1}) of N and an additional 5.0 tons (0.2 kg·ha{sup −1}) of P in the Extremadura's rice fields during winter. Additionally, we estimated that 2.3 tons of N and 550 kg of P were removed from rice fields and transported to reservoirs. The seasonal foraging of wildlife should result in a direct benefit for rice farmers by improving nutrient recycling through defecation by waterbirds with respect to artificial fertilisation. Additionally, rice fields located in the cranes' core wintering areas can provide sufficient food supply to induce habitat shift from their traditional wintering habitat in ‘dehesas’ to rice fields, which causes indirect socioeconomic benefit through reduced acorn consumption by cranes. Our modelling approach may thus be especially helpful for management decisions regarding rice agroecosystems in areas which are also important

Potential of three microbial bio-effectors to promote maize growth and nutrient acquisition from alternative phosphorous fertilizers in contrasting soils

DEFF Research Database (Denmark)

Thonar, Cécile; Lekfeldt, Jonas Duus Stevens; Cozzolino, Vincenza

2017-01-01

results were mostly obtained with BEs in combination with organic fertilizers such as composted animal manures, fresh digestate of organic wastes, and sewage sludge. In only one experiment, the nutrient use efficiency of mineral recycling fertilizers was improved by BE inoculation. Conclusions......Background: Agricultural production is challenged by the limitation of non-renewable resources. Alternative fertilizers are promoted but they often have a lower availability of key macronutrients, especially phosphorus (P). Biological inoculants, the so-called bio-effectors (BEs), may be combined...... with these fertilizers to improve the nutrient use efficiency. Methods: The goal of this study was to assess the potential of three BEs in combination with alternative fertilizers (e.g., composted manure, biogas digestate, green compost) to promote plant growth and nutrient uptake in soils typical for various European...

Waste paper for recycling: Overview and identification of potentially critical substances.

Science.gov (United States)

Pivnenko, Kostyantyn; Eriksson, Eva; Astrup, Thomas F

2015-11-01

Paper product manufacturing involves a variety of chemicals used either directly in paper and pulp production or in the conversion processes (i.e. printing, gluing) that follow. Due to economic and environmental initiatives, paper recycling rates continue to rise. In Europe, recycling has increased by nearly 20% within the last decade or so, reaching a level of almost 72% in 2012. With increasing recycling rates, lower quality paper fractions may be included. This may potentially lead to accumulation or un-intended spreading of chemical substances contained in paper, e.g. by introducing chemicals contained in waste paper into the recycling loop. This study provides an overview of chemicals potentially present in paper and applies a sequential hazard screening procedure based on the intrinsic hazard, physical-chemical and biodegradability characteristics of the substances. Based on the results, 51 substances were identified as potentially critical (selected mineral oils, phthalates, phenols, parabens, as well as other groups of chemicals) in relation to paper recycling. It is recommended that these substances receive more attention in waste paper. Copyright © 2015 Elsevier Ltd. All rights reserved.

Current organic waste recycling and the potential for local recycling through urban agriculture in Metro Manila.

Science.gov (United States)

Hara, Yuji; Furutani, Takashi; Murakami, Akinobu; Palijon, Armando M; Yokohari, Makoto

2011-11-01

Using the solid waste management programmes of three barangays (the smallest unit of local government in the Philippines) in Quezon City, Metro Manila, as a case study, this research aimed to further the development of efficient organic waste recycling systems through the promotion of urban agricultural activities on green and vacant spaces. First, the quantity of organic waste and compost produced through ongoing barangay projects was measured. The amount of compost that could potentially be utilized on farmland and vacant land within the barangays was then identified to determine the possibility of a local recycling system. The results indicate that, at present, securing buyers for compost is difficult and, therefore, most compost is distributed to large neighbouring farm villages. However, the present analysis of potential compost use within the barangay demonstrates that a more local compost recycling system is indeed feasible.

Recycling potential of post-consumer plastic packaging waste in Finland.

Science.gov (United States)

Dahlbo, Helena; Poliakova, Valeria; Mylläri, Ville; Sahimaa, Olli; Anderson, Reetta

2018-01-01

Recycling of plastics is urged by the need for closing material loops to maintain our natural resources when striving towards circular economy, but also by the concern raced by observations of plastic scrap in oceans and lakes. Packaging industry is the sector using the largest share of plastics, hence packaging dominates in the plastic waste flow. The aim of this paper was to sum up the recycling potential of post-consumer plastic packaging waste in Finland. This potential was evaluated based on the quantity, composition and mechanical quality of the plastic packaging waste generated by consumers and collected as a source-separated fraction, within the mixed municipal solid waste (MSW) or within energy waste. Based on the assessment 86,000-117,000 tons (18 kg/person/a) of post-consumer plastic packaging waste was generated in Finland in 2014. The majority, 84% of the waste was in the mixed MSW flow in 2014. Due to the launching of new sorting facilities and separate collections for post-consumer plastic packaging in 2016, almost 40% of the post-consumer plastic packaging could become available for recycling. However, a 50% recycling rate for post-consumer plastic packaging (other than PET bottles) would be needed to increase the overall MSW recycling rate from the current 41% by around two percentage points. The share of monotype plastics in the overall MSW plastics fraction was 80%, hence by volume the recycling potential of MSW plastics is high. Polypropylene (PP) and low density polyethylene (LDPE) were the most common plastic types present in mixed MSW, followed by polyethylene terephthalate (PET), polystyrene (PS) and high density polyethylene (HDPE). If all the Finnish plastic packaging waste collected through the three collection types would be available for recycling, then 19,000-25,000 tons of recycled PP and 6000-8000 tons of recycled HDPE would be available on the local market. However, this assessment includes uncertainties due to performing the

The potential environmental gains from recycling waste plastics: Simulation of transferring recycling and recovery technologies to Shenyang, China

International Nuclear Information System (INIS)

Chen Xudong; Xi Fengming; Geng Yong; Fujita, Tsuyoshi

2011-01-01

Research highlights: → Urban symbiosis creates compatibility of industrial development and waste management. → Mechanical technology leads to more CO 2 emission reduction. → Energy recovery technology leads to more fossil fuel saving. → Clean energy makes recycling technologies cleaner. → Demand management is crucial for realizing potential environmental gains of recycling. - Abstract: With the increasing attention on developing a low-carbon economy, it is necessary to seek appropriate ways on reducing greenhouse gas (GHG) emissions through innovative municipal solid waste management (MSWM), such as urban symbiosis. However, quantitative assessments on the environmental benefits of urban symbiosis, especially in developing countries, are limited because only a limited number of planned synergistic activities have been successful and it is difficult to acquire detailed inventory data from private companies. This paper modifies and applies a two-step simulation system and used it to assess the potential environmental benefits, including the reduction of GHG emissions and saving of fossil fuels, by employing various Japanese plastics recycling/energy-recovery technologies in Shenyang, China. The results showed that among various recycling/energy-recovery technologies, the mechanical waste plastics recycling technology, which produces concrete formwork boards (NF boards), has the greatest potential in terms of reducing GHG emissions (1.66 kg CO 2 e/kg plastics), whereas the technology for the production of refuse plastic fuel (RPF) has the greatest potential on saving fossil fuel consumption (0.77 kgce/kg-plastics). Additional benefits can be gained by applying combined technologies that cascade the utilization of waste plastics. Moreover, the development of clean energy in conjunction with the promotion of new waste plastics recycling programs could contribute to additional reductions in GHG emissions and fossil fuel consumption.

Closed nutrient recycling via microbial catabolism in an eco-engineered self regenerating mixed anaerobic microbiome for hydrogenotrophic methanogenesis.

Science.gov (United States)

Savvas, Savvas; Donnelly, Joanne; Patterson, Tim P; Dinsdale, Richard; Esteves, Sandra R

2017-03-01

A novel eco-engineered mixed anaerobic culture was successfully demonstrated for the first time to be capable of continuous regeneration in nutrient limiting conditions. Microbial catabolism has been found to support a closed system of nutrients able to enrich a culture of lithotrophic methanogens and provide microbial cell recycling. After enrichment, the hydrogenotrophic species was the dominating methanogens while a bacterial substratum was responsible for the redistribution of nutrients. q-PCR results indicated that 7% of the total population was responsible for the direct conversion of the gases. The efficiency of H 2 /CO 2 conversion to CH 4 reached 100% at a gassing rate of above 60v/v/d. The pH of the culture media was effectively sustained at optimal levels (pH 7-8) through a buffering system created by the dissolved CO 2 . The novel approach can reduce the process nutrient/metal requirement and enhance the environmental and financial performance of hydrogenotrophic methanogenesis for renewable energy storage. Copyright © 2016 Elsevier Ltd. All rights reserved.

Unanticipated potential cancer risk near metal recycling facilities

International Nuclear Information System (INIS)

Raun, Loren; Pepple, Karl; Hoyt, Daniel; Richner, Donald; Blanco, Arturo; Li, Jiao

2013-01-01

and the number of shifts that could operate a year. Further study is warranted to better understand the metal air pollution levels in the community and if necessary, to evaluate the feasibility of emission controls and identify operational improvements and best management practices for this industry. This research adds two new aspects to the literature: identification of types and magnitude of metal particulate matter air pollutants associated with a previously unrecognized area source, metal recyclers and their potential risk to health. -- Highlights: • Air monitoring study in response to community complaints found metal contamination. • Metal recyclers found to potentially pose cancer from metal particulates • Chromium, nickel, cobalt and cadmium samples were detected in five metal recyclers. • These metals were not detected in background air samples. • Estimated increased cancer risk ranges from 1 in 1,000,000 to 8 in 10,000

Unanticipated potential cancer risk near metal recycling facilities

Energy Technology Data Exchange (ETDEWEB)

Raun, Loren, E-mail: raun@rice.edu [Department of Statistics, MS 138, Rice University, P.O. Box 1892, Houston, TX 77251-1892 (United States); Pepple, Karl, E-mail: pepple.karl@epa.gov [State and Local Programs Group, Air Quality Policy Division, Office of Air Quality Planning and Standards, Policy, Analysis, and Communications Staff, Mail Drop C404-03, U.S. EPA, Research Triangle Park, NC 27711 (United States); Hoyt, Daniel, E-mail: hoyt.daniel@epa.gov [Air Surveillance Section, US EPA, Region 6, 6EN-AS, 1445 Ross Avenue, Dallas, TX 75202-2733 (United States); Richner, Donald, E-mail: Donald.Richner@houstontx.gov [Houston Department of Health and Human Services, Bureau of Pollution Control and Prevention, 7411 Park Place Blvd., Houston, TX 77087 (United States); Blanco, Arturo, E-mail: arturo.blanco@houstontx.gov [Pollution Control and Prevention, Environmental Health Division, Houston Department of Health and Human Services, 7411 Park Place Blvd., Houston, TX 77087 (United States); Li, Jiao, E-mail: jiao.li@rice.edu [Wiess School of Natural Science, Rice University, 6100 Main St., Houston, TX 77005 (United States)

2013-07-15

and the number of shifts that could operate a year. Further study is warranted to better understand the metal air pollution levels in the community and if necessary, to evaluate the feasibility of emission controls and identify operational improvements and best management practices for this industry. This research adds two new aspects to the literature: identification of types and magnitude of metal particulate matter air pollutants associated with a previously unrecognized area source, metal recyclers and their potential risk to health. -- Highlights: • Air monitoring study in response to community complaints found metal contamination. • Metal recyclers found to potentially pose cancer from metal particulates • Chromium, nickel, cobalt and cadmium samples were detected in five metal recyclers. • These metals were not detected in background air samples. • Estimated increased cancer risk ranges from 1 in 1,000,000 to 8 in 10,000.

Pharmaceutical consumption and residuals potentially relevant to nutrient cycling in Greater Accra, Ghana

Directory of Open Access Journals (Sweden)

Evren Sinar

2010-04-01

Full Text Available Recycling nutrients form sanitary wastes back into agricultural ecosystems offers an option to alleviate soil depletion in regions where the use of mineral fertiliser is limited. Exemplary nutrient and water cycling approaches, including collection, treatment and use of human urine, are established at Valley View University (VVU in Greater Accra, Ghana.Concerns have been recently raised in regard to fate and impact of pharmaceutical residues in soils and interlinked environment. To evaluate in how far emerging knowledge can be transposed onto VVU, urban and rural environments in Greater Accra, spatial disease occurrence and drug consumption patterns were studied. Malaria has been found to represent the most severe health burden in Ghana, but there is also a high prevalence of infectious diseases. Drugs consumed in great quantities and in respect to their residual loads potentially problematic in the environment belong to therapeutic groups of: antibiotics, analgesics, drugs for diabetes, antimalarials, cardiovascular drugs and anthelmintics. Drug consumption revealed to be highest in urban and lowest in rural areas. At VVU the range of consumed drugs is comparable to urban areas except for the negligible use of diabetes and cardiovascular medication as well as contraceptives.

Estimating Values of Carbon Sequestration and Nutrient Recycling in Forests: An Application to the Stockholm-Mälar Region in Sweden

Directory of Open Access Journals (Sweden)

Ing-Marie Gren

2015-10-01

Full Text Available We calculate values of forest carbon sequestration and nutrient recycling applying the replacement cost method. The value is then determined as the savings in costs by the replacement of more expensive abatement measures with these ecosystem services in cost-effective climate and nutrient programs. To this end, a dynamic optimization model is constructed, which accounts for uncertainty in sequestration. It is applied to the Stockholm-Mälar region in southeast Sweden where the EU 2050 climate policy for carbon emissions and the Baltic Sea action plan for nutrient discharges are applied. The results show that the value of carbon and nutrient sequestration can correspond to approximately 0.5% of the region’s gross domestic product, or 40% of the value of productive forest. The largest part of this value is attributed to carbon sequestration because of the relative stringency in targets and expensive alternative abatement measures. However, sequestration is uncertain because of stochastic weather conditions, and when society has a large risk aversion for not attaining climate and nutrient targets, the values of the forest carbon and nutrient sequestration can approach zero.

Can anaerobic digestion of sugar beet pulp support the circular economy? a study of biogas and nutrient potential

Science.gov (United States)

Suhartini, S.; Heaven, S.; Banks, C. J.

2018-03-01

Anaerobic digestion (AD), known as a biological process without oxygen to convert complex organic materials into biogas, is capable of processing large tonnage quantities of biomass, such as sugar beet pulp (SBP). In addition to biogas production, its use allows nutrients and organic carbon recycle back to agriculture through the spreading of digestate. Digestate still contains high amount of nutrients (N, P, K) for use as biofertiliser. The aims of this research were to determine biogas/methane potential as a baseline for comparison with performance in semi-continuous digestion, and to determine nutrient and potentially toxic elements (PTE) of digestate fractions with respect to their potential for utilisation in agriculture. The Biochemical Methane Potential (BMP) test was performed in triplicate against blank and positive controls over a period of 28 days with gas measured at regular intervals. Semi-continuous AD of SBP was operated under mesophilic and thermophilic condition for 206 and 165 days. The results indicated that SBP is a very promising feedstock for AD, with the average BMP of 0.321 l CH4 g-1 VS and biogas potential of 0.605 l g-1 VS. Under semi-continuous operation, SBP also demonstrated positive results. Digestates from mesophilic and thermophilic AD of SBP contained useful quantities of N, P and K, with an acceptable Ni concentration in accordance to limits for PTE. These results suggest that digestate has the potential to be utilised on agricultural and arable land. This study illustrated the positive effects of applying AD to the achievement of economic savings and environmental-friendly performance.

Characterization of wastes and their recycling potentials; A case ...

African Journals Online (AJOL)

MICHAEL HORSFALL

Key words: Solid waste, waste characterization, recycling potentials, waste scavengers. ABSTRACT: Wastes ... Waste management is the collection, transportation, processing ... wastes generated by household, commercial activities or other ...

Algal biofuels from urban wastewaters: maximizing biomass yield using nutrients recycled from hydrothermal processing of biomass.

Science.gov (United States)

Selvaratnam, T; Pegallapati, A K; Reddy, H; Kanapathipillai, N; Nirmalakhandan, N; Deng, S; Lammers, P J

2015-04-01

Recent studies have proposed algal cultivation in urban wastewaters for the dual purpose of waste treatment and bioenergy production from the resulting biomass. This study proposes an enhancement to this approach that integrates cultivation of an acidophilic strain, Galdieria sulphuraria 5587.1, in a closed photobioreactor (PBR); hydrothermal liquefaction (HTL) of the wet algal biomass; and recirculation of the nutrient-rich aqueous product (AP) of HTL to the PBR to achieve higher biomass productivity than that could be achieved with raw wastewater. The premise is that recycling nutrients in the AP can maintain optimal C, N and P levels in the PBR to maximize biomass growth to increase energy returns. Growth studies on the test species validated growth on AP derived from HTL at temperatures from 180 to 300°C. Doubling N and P concentrations over normal levels in wastewater resulted in biomass productivity gains of 20-25% while N and P removal rates also doubled. Copyright © 2015 Elsevier Ltd. All rights reserved.

Uncovering the Recycling Potential of "New" WEEE in China.

Science.gov (United States)

Zeng, Xianlai; Gong, Ruying; Chen, Wei-Qiang; Li, Jinhui

2016-02-02

Newly defined categories of WEEE have increased the types of China's regulated WEEE from 5 to 14. Identification of the amounts and valuable-resource components of the "new" WEEE generated is critical to solving the e-waste problem, for both governmental policy decisions and recycling enterprise expansions. This study first estimates and predicts China's new WEEE generation for the period of 2010-2030 using material flow analysis and the lifespan model of the Weibull distribution, then determines the amounts of valuable resources (e.g., base materials, precious metals, and rare-earth minerals) encased annually in WEEE, and their dynamic transfer from in-use stock to waste. Main findings include the following: (i) China will generate 15.5 and 28.4 million tons WEEE in 2020 and 2030, respectively, and has already overtaken the U.S. to become the world's leading producer of e-waste; (ii) among all the types of WEEE, air conditioners, desktop personal computers, refrigerators, and washing machines contribute over 70% of total WEEE by weight. The two categories of EEE-electronic devices and electrical appliances-each contribute about half of total WEEE by weight; (iii) more and more valuable resources have been transferred from in-use products to WEEE, significantly enhancing the recycling potential of WEEE from an economic perspective; and (iv) WEEE recycling potential has been evolving from ∼16 (10-22) billion US$ in 2010, to an anticipated ∼42 (26-58) billion US$ in 2020 and ∼73.4 (44.5-103.4) billion US$ by 2030. All the obtained results can improve the knowledge base for closing the loop of WEEE recycling, and contribute to governmental policy making and the recycling industry's business development.

The potential environmental gains from recycling waste plastics: simulation of transferring recycling and recovery technologies to Shenyang, China.

Science.gov (United States)

Chen, Xudong; Xi, Fengming; Geng, Yong; Fujita, Tsuyoshi

2011-01-01

With the increasing attention on developing a low-carbon economy, it is necessary to seek appropriate ways on reducing greenhouse gas (GHG) emissions through innovative municipal solid waste management (MSWM), such as urban symbiosis. However, quantitative assessments on the environmental benefits of urban symbiosis, especially in developing countries, are limited because only a limited number of planned synergistic activities have been successful and it is difficult to acquire detailed inventory data from private companies. This paper modifies and applies a two-step simulation system and used it to assess the potential environmental benefits, including the reduction of GHG emissions and saving of fossil fuels, by employing various Japanese plastics recycling/energy-recovery technologies in Shenyang, China. The results showed that among various recycling/energy-recovery technologies, the mechanical waste plastics recycling technology, which produces concrete formwork boards (NF boards), has the greatest potential in terms of reducing GHG emissions (1.66 kg CO(2)e/kg plastics), whereas the technology for the production of refuse plastic fuel (RPF) has the greatest potential on saving fossil fuel consumption (0.77 kg ce/kg-plastics). Additional benefits can be gained by applying combined technologies that cascade the utilization of waste plastics. Moreover, the development of clean energy in conjunction with the promotion of new waste plastics recycling programs could contribute to additional reductions in GHG emissions and fossil fuel consumption. Copyright © 2010 Elsevier Ltd. All rights reserved.

Waste paper for recycling: Overview and identification of potentially critical substances

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Eriksson, Eva; Astrup, Thomas Fruergaard

2015-01-01

by nearly 20% within the last decade or so, reaching a level of almost 72% in 2012. With increasing recycling rates, lower quality paper fractions may be included. This may potentially lead to accumulation or un-intended spreading of chemical substances contained in paper, e.g. by introducing chemicals...... contained in waste paper into the recycling loop. This study provides an overview of chemicals potentially present in paper and applies a sequential hazard screening procedure based on the intrinsic hazard, physical-chemical and biodegradability characteristics of the substances. Based on the results, 51...

Waste material recycling: Assessment of contaminants limiting recycling

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn

systematically investigated. This PhD project provided detailed quantitative data following a consistent approach to assess potential limitations for the presence of chemicals in relation to material recycling. Paper and plastics were used as illustrative examples of materials with well-established recycling...... schemes and great potential for increase in recycling, respectively. The approach followed in the present work was developed and performed in four distinct steps. As step one, fractional composition of waste paper (30 fractions) and plastics (9 fractions) from households in Åbenrå municipality (Southern...... detrimental to their recycling. Finally, a material flow analysis (MFA) approach revealed the potential for accumulation and spreading of contaminants in material recycling, on the example of the European paper cycle. Assessment of potential mitigation measures indicated that prevention of chemical use...

Recycling as a strategy against rare earth element criticality: a systemic evaluation of the potential yield of NdFeB magnet recycling.

Science.gov (United States)

Rademaker, Jelle H; Kleijn, René; Yang, Yongxiang

2013-09-17

End-of-life recycling is promoted by OECD countries as a promising strategy in the current global supply crisis surrounding rare earth elements (REEs) so that dependence on China, the dominant supplier, can be decreased. So far the feasibility and potential yield of REE recycling has not been systematically evaluated. This paper estimates the annual waste flows of neodymium and dysprosium from permanent magnets, the main deployment of these critical REEs, during the 2011-2030 period. The estimates focus on three key permanent magnet waste flows: wind turbines, hybrid and electric vehicles, and hard disk drives (HDDs) in personal computers (PCs). This is a good indication of the end-of-life recycling of neodymium and dysprosium maximum potential yield. Results show that for some time to come, waste flows from permanent magnets will remain small relative to the rapidly growing global REE demand. Policymakers therefore need to be aware that during the next decade recycling is unlikely to substantially contribute to global REE supply security. In the long term, waste flows will increase sharply and will meet a substantial part of the total demand for these metals. Future REE recycling efforts should, therefore, focus on the development of recycling technology and infrastructure.

Potential reuse of petroleum-contaminated soil: A directory of permitted recycling facilities

International Nuclear Information System (INIS)

Rosenthal, S.; Wolf, G.; Avery, M.; Nash, J.H.

1992-06-01

Soil contaminated by virgin petroleum products leaking from underground storage tanks is a pervasive problem in the United States. Economically feasible disposal of such soil concerns the responsible party (RP), whether the RP is one individual small business owner, a group of owners, or a large multinational corporation. They may need a starting point in their search for an appropriate solution, such as recycling. The report provides initial assistance in two important areas. First it discusses four potential recycling technologies that manufacture marketable products from recycled petroleum-contaminated soil: the hot mix asphalt process, the cold mix asphalt system, cement production, and brick manufacturing. The report also presents the results of a project survey designed to identify recycling facilities. It lists recycling facilities alphabetically by location within each state, organized by U.S. Environmental Protection Agency (EPA) Region. The report also includes detailed addresses, recycling locations, telephone numbers, and contacts for these facilities. The scope of the project limits listings to fixed facilities or small mobile facility owners that recycle soil contaminated by virgin petroleum products into marketable commodities. It does not address site-specific or commercial hazardous waste remediation facilities

The Stoichiometry of Nutrient Release by Terrestrial Herbivores and Its Ecosystem Consequences

Directory of Open Access Journals (Sweden)

Judith Sitters

2017-04-01

Full Text Available It is widely recognized that the release of nutrients by herbivores via their waste products strongly impacts nutrient availability for autotrophs. The ratios of nitrogen (N and phosphorus (P recycled through herbivore release (i.e., waste N:P are mainly determined by the stoichiometric composition of the herbivore's food (food N:P and its body nutrient content (body N:P. Waste N:P can in turn impact autotroph nutrient limitation and productivity. Herbivore-driven nutrient recycling based on stoichiometric principles is dominated by theoretical and experimental research in freshwater systems, in particular interactions between algae and invertebrate herbivores. In terrestrial ecosystems, the impact of herbivores on nutrient cycling and availability is often limited to studying carbon (C:N and C:P ratios, while the role of terrestrial herbivores in mediating N:P ratios is also likely to influence herbivore-driven nutrient recycling. In this review, we use rules and predictions on the stoichiometry of nutrient release originating from algal-based aquatic systems to identify the factors that determine the stoichiometry of nutrient release by herbivores. We then explore how these rules can be used to understand the stoichiometry of nutrient release by terrestrial herbivores, ranging from invertebrates to mammals, and its impact on plant nutrient limitation and productivity. Future studies should focus on measuring both N and P when investigating herbivore-driven nutrient recycling in terrestrial ecosystems, while also taking the form of waste product (urine or feces and other pathways by which herbivores change nutrients into account, to be able to quantify the impact of waste stoichiometry on plant communities.

How farmers in Switzerland perceive fertilizers from recycled anthropogenic nutrients (urine).

Science.gov (United States)

Lienert, J; Haller, M; Berner, A; Stauffacher, M; Larsen, T A

2003-01-01

We studied acceptance of a urine-based fertilizer product using a mail survey of 467 Swiss farmers. We distinguished among four production types: organic or IP farming, and with or without vegetable production. Considering that the idea of urine-based fertilizers is new, acceptance among the answering farmers was surprisingly high, with 57% explicitly stating that they thought it was a good or very good idea, and 42% willing to purchase such a product. The farmers of different production types did not differ strongly in their attitude towards urine-based fertilizers. Especially IP and vegetable farmers, who purchased additional fertilizers anyway, seem willing to accept urine-based fertilizers, hereby preferring a grainy, odorless ammonium nitrate fertilizer. Absolutely essential is a hazard-free product: 30% of all farmers had concerns regarding micropollutants. Based on fertilizer data, we demonstrate an existing demand for the nutrients N, P, and K in Switzerland, which could be partially substituted by a recycled urine product. Finally, we discuss methodological requirements of social science surveys. To obtain representative data on an entire population in a mail survey, multiple contacts with respondents are necessary. We argue that information and participation of stakeholders at an early stage is essential for successful technology transfer.

Sequential recycling of enzymatic lipid-extracted hydrolysate in fermentations with a thraustochytrid.

Science.gov (United States)

Lowrey, Joshua; Armenta, Roberto E; Brooks, Marianne S

2016-06-01

This study extends the findings of prior studies proposing and validating nutrient recycling for the heterotrophic microalgae, Thraustochytrium sp. (T18), grown in optimized fed-batch conditions. Sequential nutrient recycling of enzymatically-derived hydrolysate in fermentors succeeded at growing the tested thraustochytrid strain, with little evidence of inhibition or detrimental effects upon culture health. The average maximum biomass obtained in the recycled hydrolysate was 63.68±1.46gL(-1) in 90h the first recycle followed by 65.27±1.15gL(-1) in 90h in the subsequent recycle of the same material. These compared to 58.59gL(-1) and 64.92gL(-1) observed in fresh media in the same time. Lipid production was slightly impaired, however, with a maximum total fatty acid content of 62.2±0.30% in the recycled hydrolysate compared to 69.4% in fresh control media. Copyright © 2016 Elsevier Ltd. All rights reserved.

Applications of nutrient profiling: potential role in diet-related chronic disease prevention and the feasibility of a core nutrient-profiling system.

Science.gov (United States)

Sacks, G; Rayner, M; Stockley, L; Scarborough, P; Snowdon, W; Swinburn, B

2011-03-01

A number of different nutrient-profiling models have been proposed and several applications of nutrient profiling have been identified. This paper outlines the potential role of nutrient-profiling applications in the prevention of diet-related chronic disease (DRCD), and considers the feasibility of a core nutrient-profiling system, which could be modified for purpose, to underpin the multiple potential applications in a particular country. The 'Four 'P's of Marketing' (Product, Promotion, Place and Price) are used as a framework for identifying and for classifying potential applications of nutrient profiling. A logic pathway is then presented that can be used to gauge the potential impact of nutrient-profiling interventions on changes in behaviour, changes in diet and, ultimately, changes in DRCD outcomes. The feasibility of a core nutrient-profiling system is assessed by examining the implications of different model design decisions and their suitability to different purposes. There is substantial scope to use nutrient profiling as part of the policies for the prevention of DRCD. A core nutrient-profiling system underpinning the various applications is likely to reduce discrepancies and minimise the confusion for regulators, manufacturers and consumers. It seems feasible that common elements, such as a standard scoring method, a core set of nutrients and food components, and defined food categories, could be incorporated as part of a core system, with additional application-specific criteria applying. However, in developing and in implementing such a system, several country-specific contextual and technical factors would need to be balanced.

Recycling Potential of Waste Di-Isobutyl-Ketone (DIBK) and ...

African Journals Online (AJOL)

This paper investigated the possibility of using distillation to recover gold contained in the waste generated in Ghana as well as the recycling potential of the distillate (regenerated DIBK). It was established that distillation of the waste DIBK yielded about 92% distillate leaving a residue of tar, which contained all the gold in ...

PCB Food Web Dynamics Quantify Nutrient and Energy Flow in Aquatic Ecosystems.

Science.gov (United States)

McLeod, Anne M; Paterson, Gordon; Drouillard, Ken G; Haffner, G Douglas

2015-11-03

Measuring in situ nutrient and energy flows in spatially and temporally complex aquatic ecosystems represents a major ecological challenge. Food web structure, energy and nutrient budgets are difficult to measure, and it is becoming more important to quantify both energy and nutrient flow to determine how food web processes and structure are being modified by multiple stressors. We propose that polychlorinated biphenyl (PCB) congeners represent an ideal tracer to quantify in situ energy and nutrient flow between trophic levels. Here, we demonstrate how an understanding of PCB congener bioaccumulation dynamics provides multiple direct measurements of energy and nutrient flow in aquatic food webs. To demonstrate this novel approach, we quantified nitrogen (N), phosphorus (P) and caloric turnover rates for Lake Huron lake trout, and reveal how these processes are regulated by both growth rate and fish life history. Although minimal nutrient recycling was observed in young growing fish, slow growing, older lake trout (>5 yr) recycled an average of 482 Tonnes·yr(-1) of N, 45 Tonnes·yr(-1) of P and assimilated 22 TJ yr(-1) of energy. Compared to total P loading rates of 590 Tonnes·yr(-1), the recycling of primarily bioavailable nutrients by fish plays an important role regulating the nutrient states of oligotrophic lakes.

Actinide recycle potential in the integral fast reactor

International Nuclear Information System (INIS)

Chang, Y.I.

1993-01-01

The Integral Fast Reactor (IFR) fuel cycle holds promise for substantial improvements in economics, diversion-resistance, and waste management. In the IFR pyroprocessing, minor actinides accompany plutonium product stream, and therefore, actinide recycle occurs naturally. The fast neutron spectrum of the IFR makes it an ideal actinide burner, as well. This paper discusses technical features of the IFR fuel cycle, its technical progress, the development status, and potential implications on long-term waste management

Recycling of Na in advanced life support: strategies based on crop production systems.

Science.gov (United States)

Guntur, S V; Mackowiak, C; Wheeler, R M

1999-01-01

Sodium is an essential dietary requirement in human nutrition, but seldom holds much importance as a nutritional element for crop plants. In Advanced Life Support (ALS) systems, recycling of gases, nutrients, and water loops is required to improve system closure. If plants are to play a significant role in recycling of human wastes, Na will need to accumulate in edible tissues for return to the crew diet. If crops fail to accumulate the incoming Na into edible tissues, Na could become a threat to the hydroponic food production system by increasing the nutrient solution salinity. Vegetable crops of Chenopodiaceae such as spinach, table beet, and chard may have a high potential to supply Na to the human diet, as Na can substitute for K to a large extent in metabolic processes of these crops. Various strategies are outlined that include both genetic and environmental management aspects to optimize the Na recovery from waste streams and their resupply through the human diet in ALS.

Poultry feather wastes recycling possibility as soil nutrient

Directory of Open Access Journals (Sweden)

Lili Mézes

2015-10-01

Full Text Available Poultry feathers are produced in large amounts as a waste in poultry slaughterhouses. Only 60-70% of the poultry slaughterhouse products are edible for human being. This means more million tons annually worldwide (Papadopoulus et al., 1986; Williams et al., 1991; Hegedűs et al., 1998. The keratin-content of feather can be difficulty digested, so physical, chemical and/or biological pre-treatment are needed in practice, which have to be set according to the utilization method. Feather was enzymatic degraded, and then fermented in separated bioreactors. The anaerobic bioreactor system (4 digesters with 6 litre volume was controlled by ACE SCADA software running on Linux platforms. Pot scale seed germination tests were established to suggest the quantity of digested slurry to be utilized. The chosen test plants were lettuce (Lactuca sativa. In case of reproduction test Student’s t-test was applied to examine significant differences between the root lengths of the control and the treated plant species. In case of pot seed germination variance analysis with Tukey B’s and Duncan test was applied to examine significant differences between the root lengths of plants, grown on different treatments. The effect of treatments on germination ability of the plant species was expressed in the percentage of the controls. According to Student’s t-test significant difference was found between root lengths of different treatments. Based on variance analysis with Tukey B’s and Duncan tests could be detected a significant difference between the treatments. Utilization of the fermented material reduces the use of fertilizers and because of its large moisture content it reduces the watering costs. Recycle of the slaughterhouse feather and different agricultural wastes and by-products can solve three main problems: disposal of harmful materials, producing of renewable energy and soil nutrient, measuring reflectance at the certain spectral range, which can

Closed-Cycle Nutrient Supply For Hydroponics

Science.gov (United States)

Schwartzkopf, Steven H.

1991-01-01

Hydroponic system controls composition and feed rate of nutrient solution and recovers and recycles excess solution. Uses air pressure on bladders to transfer aqueous nutrient solution. Measures and adjusts composition of solution before it goes to hydroponic chamber. Eventually returns excess solution to one of tanks. Designed to operate in microgravity, also adaptable to hydroponic plant-growing systems on Earth.

Phosphorus Import Dependency and Recycling Potential in the Global Phosphorus Mosaic

Science.gov (United States)

Powers, S. M.

2017-12-01

Nations differ widely in terms of recent P consumption trends and fertilizer trade dependencies, reflecting dynamic and globally uneven P fertilizer production, consumption, export, and import. Recovered P from urban and agricultural wastes can provide renewable sources that supplant the need to import P fertilizer, but to date, research on P recycling potential has been highly spatially segregated. Understanding of the global distribution of P recycling potential and options, and how these intersect with P import dependencies, could be used to guide long-term, spatially-prioritized planning for P, food, and water security. We integrated recent data on national P fertilizer flows, subnational P use, and landscape features within a global grid to understand how these constraints on future options for P use are distributed worldwide. This analysis illustrates several regions where combinations of high population density, cropland extent, and manure P production provide islands of opportunity for P recycling in mixed crop-livestock and populous agricultural areas. At the same time, nations with lower import ratios (net P import:consumption) contained a disproportionately large share of manure-rich croplands and populous croplands. As a further demonstration of the kinds of integrated comparisons that are possible using global land use data sets in combination with P, worldwide similarities and distinctions for P emerged from a cluster analysis. These kinds of socioeconomic-geographic patterns may foretell distinct P futures as societies address spatially uneven options for P, food, and water security.

Comparative study of wastewater treatment and nutrient recycle via activated sludge, microalgae and combination systems.

Science.gov (United States)

Wang, Liang; Liu, Jinli; Zhao, Quanyu; Wei, Wei; Sun, Yuhan

2016-07-01

Algal-bacterial synergistic cultivation could be an optional wastewater treatment technology in temperate areas. In this study, a locally screened vigorous Chlorella strain was characterized and then it was used in a comparative study of wastewater treatment and nutrient recycle assessment via activated sludge (AS), microalgae and their combination systems. Chlorella sp. cultured with AS in light showed the best performance, in which case the removal efficiencies of COD, NH3-N and TP were 87.3%, 99.2% and 83.9%, respectively, within a short period of 1day. Algal-bacterial combination in light had the best settleability. Chlorella sp. contained biomass, could be processed to feed, fertilizer or fuel due to the improved quality (higher C/H/N) compared with sludge. PCR-DGGE analysis shows that two types of rhizobacteria, namely, Pseudomonas putida and Flavobacterium hauense were enriched in sludge when cultured with algae in light, serving as the basics for artificial consortium construction for improved wastewater treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Potential for recycling of slightly radioactive metals arising from decommissioning within nuclear sector in Slovakia.

Science.gov (United States)

Hrncir, Tomas; Strazovec, Roman; Zachar, Matej

2017-09-07

The decommissioning of nuclear installations represents a complex process resulting in the generation of large amounts of waste materials containing various concentrations of radionuclides. Selection of an appropriate strategy of management of the mentioned materials strongly influences the effectiveness of decommissioning process keeping in mind safety, financial and other relevant aspects. In line with international incentives for optimization of radioactive material management, concepts of recycling and reuse of materials are widely discussed and applications of these concepts are analysed. Recycling of some portion of these materials within nuclear sector (e.g. scrap metals or concrete rubble) seems to be highly desirable from economical point of view and may lead to conserve some disposal capacity. However, detailed safety assessment along with cost/benefit calculations and feasibility study should be developed in order to prove the safety, practicality and cost effectiveness of possible recycling scenarios. Paper discussed the potential for recycling of slightly radioactive metals arising from decommissioning of NPPs within nuclear sector in Slovakia. Various available recycling scenarios are introduced and method for overall assessment of various recycling scenarios is outlined including the preliminary assessment of safety and financial aspects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Auditing an intensive care unit recycling program.

Science.gov (United States)

Kubicki, Mark A; McGain, Forbes; O'Shea, Catherine J; Bates, Samantha

2015-06-01

The provision of health care has significant direct environmental effects such as energy and water use and waste production, and indirect effects, including manufacturing and transport of drugs and equipment. Recycling of hospital waste is one strategy to reduce waste disposed of as landfill, preserve resources, reduce greenhouse gas emissions, and potentially remain fiscally responsible. We began an intensive care unit recycling program, because a significant proportion of ICU waste was known to be recyclable. To determine the weight and proportion of ICU waste recycled, the proportion of incorrect waste disposal (including infectious waste contamination), the opportunity for further recycling and the financial effects of the recycling program. We weighed all waste and recyclables from an 11-bed ICU in an Australian metropolitan hospital for 7 non-consecutive days. As part of routine care, ICU waste was separated into general, infectious and recycling streams. Recycling streams were paper and cardboard, three plastics streams (polypropylene, mixed plastics and polyvinylchloride [PVC]) and commingled waste (steel, aluminium and some plastics). ICU waste from the waste and recycling bins was sorted into those five recycling streams, general waste and infectious waste. After sorting, the waste was weighed and examined. Recycling was classified as achieved (actual), potential and total. Potential recycling was defined as being acceptable to hospital protocol and local recycling programs. Direct and indirect financial costs, excluding labour, were examined. During the 7-day period, the total ICU waste was 505 kg: general waste, 222 kg (44%); infectious waste, 138 kg (27%); potentially recyclable waste, 145 kg (28%). Of the potentially recyclable waste, 70 kg (49%) was actually recycled (14% of the total ICU waste). In the infectious waste bins, 82% was truly infectious. There was no infectious contamination of the recycling streams. The PVC waste was 37% contaminated

Recycling potential for low voltage and high voltage high rupturing capacity fuse links.

Science.gov (United States)

Psomopoulos, Constantinos S; Barkas, Dimitrios A; Kaminaris, Stavros D; Ioannidis, George C; Karagiannopoulos, Panagiotis

2017-12-01

Low voltage and high voltage high-rupturing-capacity fuse links are used in LV and HV installations respectively, protecting mainly the LV and HV electricity distribution and transportation networks. The Waste Electrical and Electronic Equipment Directive (2002/96/EC) for "Waste of electrical and electronic equipment" is the main related legislation and as it concerns electrical and electronic equipment, it includes electric fuses. Although, the fuse links consist of recyclable materials, only small scale actions have been implemented for their recycling around Europe. This work presents the possibilities for material recovery from this specialized industrial waste for which there are only limited volume data. Furthermore, in order to present the huge possibilities and environmental benefits, it presents the potential for recycling of HRC fuses used by the Public Power Corporation of Greece, which is the major consumer for the country, but one of the smallest ones in Europe and globally, emphasizing in this way in the issue. According to the obtained results, fuse recycling could contribute to the effort for minimize the impacts on the environment through materials recovery and reduction of the wastes' volume disposed of in landfills. Copyright © 2017 Elsevier Ltd. All rights reserved.

Energy-neutral sustainable nutrient recovery incorporated with the wastewater purification process in an enlarged microbial nutrient recovery cell

Science.gov (United States)

Sun, Dongya; Gao, Yifan; Hou, Dianxun; Zuo, Kuichang; Chen, Xi; Liang, Peng; Zhang, Xiaoyuan; Ren, Zhiyong Jason; Huang, Xia

2018-04-01

Recovery of nutrient resources from the wastewater is now an inevitable strategy to maintain the supply of both nutrient and water for our huge population. While the intensive energy consumption in conventional nutrient recovery technologies still remained as the bottleneck towards the sustainable nutrient recycle. This study proposed an enlarged microbial nutrient recovery cell (EMNRC) which was powered by the energy contained in wastewater and achieved multi-cycle nutrient recovery incorporated with in situ wastewater treatment. With the optimal recovery solution of 3 g/L NaCl and the optimal volume ratio of wastewater to recovery solution of 10:1, >89% of phosphorus and >62% of ammonium nitrogen were recovered into struvite. An extremely low water input ratio of water. It was proved the EMNRC system was a promising technology which could utilize the chemical energy contained in wastewater itself and energy-neutrally recover nutrient during the continuous wastewater purification process.

Efficient nitrogen recycling through sustainable use of organic wastes in agriculture - an Australian case study

Science.gov (United States)

Rigby, Hannah; Landman, Michael; Collins, David; Walton, Katrina; Penney, Nancy; Pritchard, Deborah

2014-05-01

The effective recycling of nutrients in treated sewage sludge (biosolids) domestic (e.g. source separated food waste), agricultural, and commercial and industrial (C&I) biowastes (e.g. food industry wastes, papermill sludge) for use on land, generally following treatment (e.g. composting, anaerobic digestion or thermal conversion technologies) as alternatives to conventional mineral fertilisers in Australia can have economic benefits, ensure food security, and close the nutrient loop. In excess of 75% of Australian agricultural soils have less than 1% organic matter (OM), and, with 40 million tonnes of solid waste per year potentially available as a source of OM, biowastes also build soil carbon (C) stocks that improve soil structure, fertility and productivity, and enhance soil ecosystem services. In recent years, the increasing cost of conventional mineral fertilisers, combined with changing weather patterns have placed additional pressure on regional and rural communities. Nitrogen (N) is generally the most limiting nutrient to crop production, and the high-energy required and GHGs associated with its manufacture mean that, additionally, it is critical to use N efficiently and recycle N resources where possible. Biosolids and biowastes have highly variable organic matter (OM) and nutrient contents, with N often present in a variety of forms only some of which are plant-available. The N value is further influenced by treatment process, storage and fundamental soil processes. The correct management of N in biowastes is essential to reduce environmental losses through leaching or runoff and negative impacts on drinking water sources and aquatic ecosystems. Gaseous N emissions also impact upon atmospheric quality and climate change. Despite the body of work to investigate N supply from biosolids, recent findings indicate that historic and current management of agricultural applications of N from biosolids and biowastes in Australia may still be inefficient leading

Nutrient fluxes at the landscape level and the R* rule

Science.gov (United States)

Ju, Shu; DeAngelis, Donald L.

2010-01-01

Nutrient cycling in terrestrial ecosystems involves not only the vertical recycling of nutrients at specific locations in space, but also biologically driven horizontal fluxes between different areas of the landscape. This latter process can result in net accumulation of nutrients in some places and net losses in others. We examined the effects of such nutrient-concentrating fluxes on the R* rule, which predicts that the species that can survive in steady state at the lowest level of limiting resource, R*, can exclude all competing species. To study the R* rule in this context, we used a literature model of plant growth and nutrient cycling in which both nutrients and light may limit growth, with plants allocating carbon and nutrients between foliage and roots according to different strategies. We incorporated the assumption that biological processes may concentrate nutrients in some parts of the landscape. We assumed further that these processes draw nutrients from outside the zone of local recycling at a rate proportional to the local biomass density. Analysis showed that at sites where there is a sufficient biomass-dependent accumulation of nutrients, the plant species with the highest biomass production rates (roughly corresponding to the best competitors) do not reduce locally available nutrients to a minimum concentration level (that is, minimum R*), as expected from the R* rule, but instead maximize local nutrient concentration. These new results require broadening of our understanding of the relationships between nutrients and vegetation competition on the landscape level. The R* rule is replaced by a more complex criterion that varies across a landscape and reduces to the R* rule only under certain limiting conditions.

Quality assessment of mined MSW from an open dumpsite for recycling potential

Energy Technology Data Exchange (ETDEWEB)

Prechthai, Tawach; Padmasri, Maddala; Visvanathan, Chettiyappan [Environmental Engineering and Management Program, School of Environment, Resources and Development, Asian Institute of Technology, PO Box 4, Klong Luang Pathumthani 12120 (Thailand)

2008-12-15

A study on recycling potential was performed on the stabilized municipal solid waste from Nonthaburi dumpsite in Thailand. The waste was excavated and subjected to separation process using trommel screen with screen openings of 25 mm and 50 mm. The screened wastes were classified into three fractions based on the sizes such as fine fraction (<25 mm), medium fraction (25-50 mm) and large fraction (>50 mm). The waste composition, physical and chemical characteristics of each waste fraction were determined to evaluate suitability of waste for recycling. The possible phytotoxicity of waste to be used as compost was explored by conducting seed germination and root elongation test of rice plant (Oryza sativa L.). The dumpsite was observed to be heterogeneous and mainly composed of plastics and soil. The trommel screen, proved to be effective in separating the waste fractions that can be used as feedstock for alternative applications of solid waste, particularly where the metal content of the product is a critical parameter. By screening, approximately 69% of soil was removed from waste and the remaining 31% was found in the waste fractions >50 mm size. The quality of waste fraction >50 mm composed mainly of plastics showed high potential for recycling as refuse derived fuel (RDF) and waste fraction <25 mm with soil as compost. The remaining waste fractions between 25 mm and 50 mm composed of non-combustible waste, which needs to be landfilled. (author)

Ash recycling to spruce and beech stands effects on nutrients, growth, nitrogen dynamics and carbon balance; Askaaterfoering till gran- och bokbestaand - effekter paa naering, tillvaext, kvaevedynamik och kolbalans

Energy Technology Data Exchange (ETDEWEB)

Thelin, Gunnar

2006-03-15

Ash recycling is an important part in a modern, sustainable forestry, especially in whole-tree harvest systems. Nutrients lost at harvest are returned to the forest with the wood-ash. In the project the effects of ash treatment on needle and leaf chemistry, tree growth, soil chemistry, soil water chemistry, and carbon and nitrogen dynamics were studied on 23 Norway spruce sites in south-western Sweden and in ten European beech sites in Scania, southern Sweden. On some of the sites there were previously established ash recycling experiments, but on a majority of the sites ash recycling was performed without experimental lay-out and ash and control plots were established afterwards. The most common dose was two tons of self hardened crushed wood-ash and two tons of Mg-lime. On average seven to eight years after ash recycling the results were 1. increased exchangeable stores of base cations in the soil in the beech and the spruce stands 2. increased base saturation in the beech and the spruce stands and increased BC/Al in the spruce stands 3. increased concentrations and ratios to N of P, Ca, Zn, and S in the needles, the increased P-values are especially important since P is close to or below deficiency levels in a majority of the spruce stands 4. decreased K-concentration in the beech leaves 5. increased tree growth with on average 14 % in the ash treated spruce stands compared to the control plots 6. increased carbon and nitrogen amounts in the biomass in the spruce stands 7. tendencies towards increased amounts of carbon and nitrogen in the soil in the beech stands and no effect in the soil in the spruce stands 8. increased concentrations of Ca, Mg, and SO{sub 4} and no effect on ANC in the soil water 9. no effect on potential net mineralization but increased potential nitrification rates 10. decreased concentration of nitrate in the soil water in the beech stands and no effect in the spruce stands 11. lower system N losses in the beech stands and possibly in the

A methodology for estimating potential doses and risks from recycling U.S. Department of Energy radioactive scrap metals

International Nuclear Information System (INIS)

MacKinney, J.A.

1995-01-01

The U.S. Environmental Protection Agency (EPA) is considering writing regulations for the controlled use of materials originating from radioactively contaminated zones which may be recyclable. These materials include metals, such as steel (carbon and stainless), nickel, copper, aluminum and lead, from the decommissioning of federal, and non-federal facilities. To develop criteria for the release of such materials, a risk analysis of all potential exposure pathways should be conducted. These pathways include direct exposure to the recycled material by the public and workers, both individual and collective, as well as numerous other potential exposure pathways in the life of the material. EPA has developed a risk assessment methodology for estimating doses and risks associated with recycling radioactive scrap metals. This methodology was applied to metal belonging to the U.S. Department of Energy. This paper will discuss the draft EPA risk assessment methodology as a tool for estimating doses and risks from recycling. (author)

Lamps recycling aiming at the environment preservation

International Nuclear Information System (INIS)

Yamachita, Roberto Akira; Gama, Paulo Henrique R. Pereira; Haddad, Jamil; Santos, Afonso H. Moreira; Guardia, Eduardo C.

1999-01-01

The article discusses the following issues of lamps recycling in Brazil: mercury lamps recycling, recycling potential, energy conservation and environmental impacts, enterprises lamps recycling, and incentives policy

Nutrients in the Western Wadden Sea: Freshwater Input Versus Internal Recycling

NARCIS (Netherlands)

Leote, C.; Mulder, L.; Philippart, C.J.; Epping, E.

2016-01-01

At present, phosphorus (P) is seen as the main limiting nutrient for phytoplankton growth in the western Wadden Sea. Six cruises were performed for water sampling at selected stations covering a full tidal cycle for later determination of dissolved and particulate nutrient concentrations. The major

Large-scale ash recycling in Central Sweden; Storskalig askhantering i mellansverige

Energy Technology Data Exchange (ETDEWEB)

Hansson, Mats [Stora Skog (Sweden)

1998-08-01

When logging residues (tops, branches) are withdrawn from the forest, most of the nutrient content of the trees is also lost. Some of the nutrient content of the soil is restored by weathering, but not all. When biomass is burnt as fuel most of the nutrients will be found in the ash. By recycling wood ash, in similar amounts as was withdrawn with the biomass, it is possible to compensate for the nutrient losses. This project was initiated to study how a rational recycling of wood ash could be performed under conditions valid for Stora, a large forest company in the middle of Sweden. A second aim was to give guiding principles for Stora`s own ash recycling while awaiting instructions from the authorities. In the project both theoretical studies and practical field studies were carried out. Studied areas are production of a stabilised ash product and different systems for transport and spreading of the ash product. The costs and results of spreading have also been monitored. The project showed that spreading of the ash can normally only take place when there is no snow. If production or transport is carried out during another time of the year, the ash has to be stored, either at the industry, in an intermediate storage, or in the forest. One important conclusion from the test period was that the result of the spreading depends heavily on the quality of the ash. Some of the ashes hardened in the spreading equipment, causing a complete stop of the spreading. It also caused problems if the ash was too wet. Plate-spreaders led to unequal quality of spreading, where some areas got more ash and some got less. Granulated ash was most easy to spread. Recommended system for spreading ash is: granulated ash transported unpacked in separate transports with lorries with exchangeable platforms. A large fores tractor spreads the ash in clearings, in the summer. The project has shown that large-scale ash recycling is possible to realize 22 figs, 5 tabs, 13 appendices

Challenges in plastics recycling

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Jakobsen, L. G.; Eriksen, Marie Kampmann

2015-01-01

Recycling of waste plastics still remains a challenging area in the waste management sector. The current and potential goals proposed on EU or regional levels are difficult to achieve, and even to partially fullfil them the improvements in collection and sorting should be considerable. A study...... was undertaken to investigate the factors affecting quality in plastics recycling. The preliminary results showed factors primarily influencing quality of plastics recycling to be polymer cross contamination, presence of additives, non-polymer impurities, and polymer degradation. Deprivation of plastics quality......, with respect to recycling, has been shown to happen throughout the plastics value chain, but steps where improvements may happen have been preliminary identified. Example of Cr in plastic samples analysed showed potential spreading and accumulation of chemicals ending up in the waste plastics. In order...

Recycling of concrete

International Nuclear Information System (INIS)

Halaszovich, S.

1988-01-01

The paper reviews potentials and problems of disposal or recycling of concrete removed from nuclear installations. Due to the difficulties in determining radioactivity limits that are compatible with utilization of recycled material in practice, a method is proposed that takes into account inhalation of dusts, as occurring during the reprocessing or recycling of the concrete, for instance in road building. This method is based on the maximum permissible radioactivity uptake by inhalation of a nuclide mixture of unknown composition. (RB) [de

Genetic incorporation of recycled unnatural amino acids.

Science.gov (United States)

Ko, Wooseok; Kim, Sanggil; Jo, Kyubong; Lee, Hyun Soo

2016-02-01

The genetic incorporation of unnatural amino acids (UAAs) into proteins has been a useful tool for protein engineering. However, most UAAs are expensive, and the method requires a high concentration of UAAs, which has been a drawback of the technology, especially for large-scale applications. To address this problem, a method to recycle cultured UAAs was developed. The method is based on recycling a culture medium containing the UAA, in which some of essential nutrients were resupplemented after each culture cycle, and induction of protein expression was controlled with glucose. Under optimal conditions, five UAAs were recycled for up to seven rounds of expression without a decrease in expression level, cell density, or incorporation fidelity. This method can generally be applied to other UAAs; therefore, it is useful for reducing the cost of UAAs for genetic incorporation and helpful for expanding the use of the technology to industrial applications.

Characterization of sewage sludge generated in Rio de Janeiro, Brazil, and perspectives for agricultural recycling

Directory of Open Access Journals (Sweden)

Alan Henrique Marques de Abreu

2017-08-01

Full Text Available Sanitary sewage collection and treatment is a serious environmental problem in Brazilian cities, as well as the destination of solid waste resulting from this process, i.e. the sewage sludge, a substance rich in organic matter and nutrients, which is normally discarded in landfills. The aim of this study was to characterize the sewage sludge generated in four treatment stations in Rio de Janeiro State, Brazil and check if they meet the legal criteria of the National Environment Council (CONAMA, Resolution No. 375/2006. It also focused on analyzing the perspectives for its agricultural recycling based on the potential demand for main agricultural crops grown in Rio de Janeiro State. Samples from eight sewage sludge lots from four treatment stations located in the metropolitan area of Rio de Janeiro were analyzed. These stations receive and treat only domestic sewage by activated sludge system. For chemical and biological characterization of these lots, representative samples were collected and analyzed according to parameters of CONAMA Resolution No. 375/2006. In order to analyze the perspectives of agricultural recycling of sewage sludge in Rio de Janeiro State, 10 crops with the largest cultivated area in the state were surveyed and analyzed which of them are apt to receive sewage sludge as fertilizer and/or soil amendment. To determine the potential demand for sewage sludge in agriculture, the area occupied by these crops were multiplied by each fertilizer recommendation considering the sewage sludge as fertilizer. The analyzed sludge presented a high content of nutrients and organic matter and was included in the parameters of heavy metals, pathogenic agents, and bacteriological indicators stipulated by CONAMA Resolution No. 375/2006. The agricultural panorama of Rio de Janeiro State is favorable for agricultural recycling of sewage sludge since there is a great potential demand for this residue and, among the 10 agricultural crops with the

The importance of recycling - Responsible recycling

International Nuclear Information System (INIS)

Svensson, Joens Petter

2014-01-01

. Environmental issues and their potential solutions are often presented in a very complex way. But the benefits from recycling are very clear, with more recycling we stand to gain economic and environmental benefits that's easy to measure. (author)

Nutrient spiraling in streams and river networks

Science.gov (United States)

Ensign, Scott H.; Doyle, Martin W.

2006-12-01

Over the past 3 decades, nutrient spiraling has become a unifying paradigm for stream biogeochemical research. This paper presents (1) a quantitative synthesis of the nutrient spiraling literature and (2) application of these data to elucidate trends in nutrient spiraling within stream networks. Results are based on 404 individual experiments on ammonium (NH4), nitrate (NO3), and phosphate (PO4) from 52 published studies. Sixty-nine percent of the experiments were performed in first- and second-order streams, and 31% were performed in third- to fifth-order streams. Uptake lengths, Sw, of NH4 (median = 86 m) and PO4 (median = 96 m) were significantly different (α = 0.05) than NO3 (median = 236 m). Areal uptake rates of NH4 (median = 28 μg m-2 min-1) were significantly different than NO3 and PO4 (median = 15 and 14 μg m-2 min-1, respectively). There were significant differences among NH4, NO3, and PO4 uptake velocity (median = 5, 1, and 2 mm min-1, respectively). Correlation analysis results were equivocal on the effect of transient storage on nutrient spiraling. Application of these data to a stream network model showed that recycling (defined here as stream length ÷ Sw) of NH4 and NO3 generally increased with stream order, while PO4 recycling remained constant along a first- to fifth-order stream gradient. Within this hypothetical stream network, cumulative NH4 uptake decreased slightly with stream order, while cumulative NO3 and PO4 uptake increased with stream order. These data suggest the importance of larger rivers to nutrient spiraling and the need to consider how stream networks affect nutrient flux between terrestrial and marine ecosystems.

Aspects to consider for optimizing a substrate culture system with drainage recycling

Directory of Open Access Journals (Sweden)

William J Cuervo B

2012-09-01

Full Text Available In Colombia, the soilless system has been implemented in the cut flowers industry, among others, due to soil limitations. The use of substrates as growing media implies to drain around 30% of the applied fertigation solution to avoid the rhizosphere salinization. The drainage solution is spilled out to the soil producing environmental hazards and it might reach the water table; although the drainage solution could be recycled or reuse, depending upon their chemical characteristics. The nutrient uptake by the plants depends upon their phenological stage and the nutrient concentration in the solution; which could lead to ion depletion or accumulation. In general, monovalent ions are withdrawn faster than divalent ones. An efficient drainage treatment involves the automation of sensing and evaluation of ion concentration and recycling the drainage solution. The system should take into account the chemical aspects in the recycled and the new solutions in order to predict the life time of the drainage solution from their EC and pH. The system must be integrated with disinfection methods to avoid the spreading of plant pathogens. This review point out the physiological and technical bases that should be taking into account in a drainage recycling system in established crops under substrates, as a tool to take decisions more efficiently.

Implementing a campus wide recycling program

International Nuclear Information System (INIS)

Alvarez, L.

2002-01-01

'Full text:' The University of Windsor is currently expanding its recycling program to include all buildings on campus, but faces two challenges: 1) uncertainty about the current waste composition and distribution on campus; and 2) uncertainty about the effectiveness of increased recycling. This project assesses the current waste composition and the attitudes of the students towards recycling, and evaluates the effectiveness of proposed recycling activities. At present, paper is the only material that is collected throughout the entire campus. Except for two buildings, all other potentially recyclable materials within buildings, such as metal, glass, and plastic beverage containers, are discarded. The main focus of this research is on beverage containers as they represent clearly identifiable materials, but other materials were examined as well. To quantify the waste, different buildings on campus were classified according to their function: academic,operational and administrative. The waste composition study indicated that approximately 33% of the campus waste which is landfilled is composed of potentially recyclable material. A survey was then conducted to gauge the campus population's views on recycling issues that could affect the design of a recycling program. Interestingly, 97% of the respondents indicated a high willingness to recycle, but were uncertain as to how and where to recycle on campus. The project is currently assessing potential diversion rates using new, clearly identifiable recycling receptacles placed within selected classrooms for all major materials. There is a significant tradeoff however because the cost for new receptacles is considerable: multiple materials containers are often placed in high pedestrian traffic locations (e.g., hallways) and not always in classrooms,of which there are often many. This project will evaluate the basic benefits and costs of implementing a more comprehensive recycling program, and recommend how other

Nutrient discharge from China’s aquaculture industry and associated environmental impacts

Science.gov (United States)

Zhang, Ying; Bleeker, Albert; Liu, Junguo

2015-04-01

China’s aquaculture industry accounts for the largest share of the world’s fishery production, and provides a principal source of protein for the nation’s booming population. However, the environmental effects of the nutrient loadings produced by this industry have not been systematically studied or reviewed. Few quantitative estimates exist for nutrient discharge from aquaculture and the resultant nutrient enrichment in waters and sediments. In this paper, we evaluate nutrient discharge from aquacultural systems into aquatic ecosystems and the resulting nutrient enrichment of water and sediments, based on data from 330 cases in 51 peer-reviewed publications. Nitrogen use efficiency ranged from 11.7% to 27.7%, whereas phosphorus use efficiency ranged from 8.7% to 21.2%. In 2010, aquacultural nutrient discharges into Chinese aquatic ecosystems included 1044 Gg total nitrogen (184 Gg N from mariculture; 860 Gg N freshwater culture) and 173 Gg total phosphorus (22 Gg P from mariculture; 151 Gg P from freshwater culture). Water bodies and sediments showed high levels of nutrient enrichment, especially in closed pond systems. However, this does not mean that open aquacultural systems have smaller nutrient losses. Improvement of feed efficiency in cage systems and retention of nutrients in closed systems will therefore be necessary. Strategies to increase nutrient recycling, such as integrated multi-trophic aquaculture, and social measures, such as subsidies, should be increased in the future. We recommend the recycling of nutrients in water and sediments by hybrid agricultural-aquacultural systems and the adoption of nutrient use efficiency as an indicator at farm or regional level for the sustainable development of aquaculture; such indicators; together with water quality indicators, can be used to guide evaluations of technological, policy, and economic approaches to improve the sustainability of Chinese aquaculture.

Analysis of the electric conductivity and pH behaviors in recycled drainage solution of rose cv. Charlotte plants grown in substrate

Directory of Open Access Journals (Sweden)

Luis Fernando Yepes V

2013-12-01

Full Text Available In open soilless cropping systems contamination from nutrient lixiviation is generated making it necessary to design closed or semi-closed systems, which require the determination of the maximum saline levels in recycling solutions. In this study, the electric conductivity (EC and pH behaviors were analyzed in drainage solution intended for recycling in the crop; in addition, parameters were used to estimate nutrient availability for the plants in a substrate based cropping system. This research project was carried out under greenhouse conditions in the municipality of Mosquera (Colombia. Rose cv. Charlotte grafted on "Natal briar" stocks were used, sown in pots arranged on elevated beds, 15 m in length. This project was carried out using a split-plot design with sub-plots (with the substrate as the main plot and the recycling as the sub-plot, three kinds of substrate and three recycling percentages (0, 50, and 100%, for a total of 27 experimental units. Substrate mixtures based on burned rice husk and coconut fiber were used. Recycling during one harvest cycle of the roses did not show EC and pH values above those that are considered to have a negative impact on production; however, an increasing behavior in the EC and pH values was observed. Likewise, no significant differences between the 50 and 100% recycling were observed, which means 100% recycling can be used, optimizing nutrient use and water conservation

Experimental investigation of the quality characteristics of agricultural plastic wastes regarding their recycling and energy recovery potential

International Nuclear Information System (INIS)

Briassoulis, D.; Hiskakis, M.; Babou, E.; Antiohos, S.K.; Papadi, C.

2012-01-01

Highlights: ► Definition of parameters characterising agricultural plastic waste (APW) quality. ► Analysis of samples to determine APW quality for recycling or energy recovery. ► Majority of APW samples from various countries have very good quality for recycling. ► Upper limit of 50% w/w soil contamination in APW acceptable for energy recovery. ► Chlorine and heavy metals content in APW below the lowest limit for energy recovery. - Abstract: A holistic environmentally sound waste management scheme that transforms agricultural plastic waste (APW) streams into labelled guaranteed quality commodities freely traded in open market has been developed by the European research project LabelAgriWaste. The APW quality is defined by the APW material requirements, translated to technical specifications, for recycling or energy recovery. The present work investigates the characteristics of the APW quality and the key factors affecting it from the introduction of the virgin product to the market to the APW stream reaching the disposer. Samples of APW from different countries were traced from their application to the field through their storage phase and transportation to the final destination. The test results showed that the majority of APW retained their mechanical properties after their use preserving a “very good quality” for recycling in terms of degradation. The degree of soil contamination concerning the APW recycling and energy recovery potential fluctuates depending on the agricultural plastic category and application. The chlorine and heavy metal content of the tested APW materials was much lower than the maximum acceptable limits for their potential use in cement industries.

Impacts of light shading and nutrient enrichment geo-engineering approaches on the productivity of a stratified, oligotrophic ocean ecosystem.

Science.gov (United States)

Hardman-Mountford, Nick J; Polimene, Luca; Hirata, Takafumi; Brewin, Robert J W; Aiken, Jim

2013-12-06

Geo-engineering proposals to mitigate global warming have focused either on methods of carbon dioxide removal, particularly nutrient fertilization of plant growth, or on cooling the Earth's surface by reducing incoming solar radiation (shading). Marine phytoplankton contribute half the Earth's biological carbon fixation and carbon export in the ocean is modulated by the actions of microbes and grazing communities in recycling nutrients. Both nutrients and light are essential for photosynthesis, so understanding the relative influence of both these geo-engineering approaches on ocean ecosystem production and processes is critical to the evaluation of their effectiveness. In this paper, we investigate the relationship between light and nutrient availability on productivity in a stratified, oligotrophic subtropical ocean ecosystem using a one-dimensional water column model coupled to a multi-plankton ecosystem model, with the goal of elucidating potential impacts of these geo-engineering approaches on ecosystem production. We find that solar shading approaches can redistribute productivity in the water column but do not change total production. Macronutrient enrichment is able to enhance the export of carbon, although heterotrophic recycling reduces the efficiency of carbon export substantially over time. Our results highlight the requirement for a fuller consideration of marine ecosystem interactions and feedbacks, beyond simply the stimulation of surface blooms, in the evaluation of putative geo-engineering approaches.

Treatment of biofuel ashes for forest recycling

International Nuclear Information System (INIS)

Bjurstroem, H.; Sjoeblom, R.

1997-03-01

Logging residues are the easiest available fuel for an increased production of energy in Sweden from renewable sources. A consequence of their removal from the forest is that the cycle of mineral nutrients is broken. The purpose of recycling the ash after this fuel to forest land is to compensate for the removal and close again the nutrient cycle. Recycling nutrients and returning the inorganic components of the biomass removed from the forest should be performed in accordance with general principles of environmental protection, health considerations and the good house-keeping of natural resources. The activities should also be carried out in accordance with the needs of the forest and energy plant owners regarding good technology and economy. This implies that functional requirements originating from these principles and needs should be clearly structured and formulated and that such requirements should provide a basis for the continued development work as well as for the implementation of suitable, economical and efficient systems. Returning inorganic constituents implies that the principle of recirculation is followed as well as that nutrients are brought back which improves accretion in the forest. At the same time, the risk of damage to the forest can be assessed as insignificant. Furthermore the risks to human health are also assessed to be insignificant provided that pertinent precautions are taken to avoid dusting. In the present report, technical and economical aspects of importance for the selection of method as well as for the establishment of a system are described and discussed. The need for further development work is identified in the following areas: functional requirements - operational requirements, sampling, testing and quality assurance, granulation, curing processes and drying/sintering. 102 refs, 1 fig, 2 tabs

Nutrients valorisation via Duckweed-based wastewater treatment and aquaculture

NARCIS (Netherlands)

Mohamed El-Shafai, S.A.A.

2004-01-01

Development of a sustainable wastewater treatment scheme to recycle sewage nutrients and water in tilapia aquaculture was the main objective of this PhD research. Use of an Integrated UASB-duckweed ponds system for domestic wastewater treatment linked to tilapia aquaculture was investigated.

Advances in the understanding of nutrient dynamics and management in UK agriculture

International Nuclear Information System (INIS)

Dungait, Jennifer A.J.; Cardenas, Laura M.; Blackwell, Martin S.A.; Wu, Lianhai; Withers, Paul J.A.; Chadwick, David R.; Bol, Roland; Murray, Philip J.; Macdonald, Andrew J.; Whitmore, Andrew P.; Goulding, Keith W.T.

2012-01-01

Current research on macronutrient cycling in UK agricultural systems aims to optimise soil and nutrient management for improved agricultural production and minimise effects on the environment and provision of ecosystem services. Nutrient use inefficiencies can cause environmental pollution through the release of greenhouse gases into the atmosphere and of soluble and particulate forms of N, P and carbon (C) in leachate and run-off into watercourses. Improving nutrient use efficiencies in agriculture calls for the development of sustainable nutrient management strategies: more efficient use of mineral fertilisers, increased recovery and recycling of waste nutrients, and, better exploitation of the substantial inorganic and organic reserves of nutrients in the soil. Long-term field experimentation in the UK has provided key knowledge of the main nutrient transformations in agricultural soils. Emerging analytical technologies, especially stable isotope labelling, that better characterise macronutrient forms and bioavailability and improve the quantification of the complex relationships between the macronutrients in soils at the molecular scale, are augmenting this knowledge by revealing the underlying processes. The challenge for the future is to determine the relationships between the dynamics of N, P and C across scales, which will require both new modelling approaches and integrated approaches to macronutrient cycling. -- Highlights: ► Major advances in the knowledge of macronutrient cycling in agricultural soils are reviewed in the context of management. ► Novel analytical techniques and innovative modelling approaches that enhance understanding of nutrient cycling are explored. ► Knowledge gaps are identified, and the potential to improve comprehension of the integrated nutrient cycles is considered.

Nutrients in estuaries - An overview and the potential impacts of climate change

Energy Technology Data Exchange (ETDEWEB)

Statham, Peter J., E-mail: pjs@noc.soton.ac.uk

2012-09-15

The fate and cycling of macronutrients introduced into estuaries depend upon a range of interlinked processes. Hydrodynamics and morphology in combination with freshwater inflow control the freshwater flushing time, and the timescale for biogeochemical processes to operate that include microbial activity, particle-dissolved phase interactions, and benthic exchanges. In some systems atmospheric inputs and exchanges with coastal waters can also be important. Climate change will affect nutrient inputs and behaviour through modifications to temperature, wind patterns, the hydrological cycle, and sea level rise. Resulting impacts include: 1) inundation of freshwater systems 2) changes in stratification, flushing times and phytoplankton productivity 3) increased coastal storm activity 4) changes in species and ecosystem function. A combination of continuing high inputs of nutrients through human activity and climate change is anticipated to lead to enhanced eutrophication in the future. The most obvious impacts of increasing global temperature will be in sub-arctic systems where permafrost zones will be reduced in combination with enhanced inputs from glacial systems. Improved process understanding in several key areas including cycling of organic N and P, benthic exchanges, resuspension, impact of bio-irrigation, particle interactions, submarine groundwater discharges, and rates and magnitude of bacterially-driven recycling processes, is needed. Development of high frequency in situ nutrient analysis systems will provide data to improve predictive models that need to incorporate a wider variety of key factors, although the complexity of estuarine systems makes such modelling a challenge. However, overall a more holistic approach is needed to effectively understand, predict and manage the impact of macronutrients on estuaries. -- Highlights: Black-Right-Pointing-Pointer Estuarine macronutrient behaviour defined by both physical and biogeochemical processes. Black

Additive Manufacturing of Syntactic Foams: Part 1: Development, Properties, and Recycling Potential of Filaments

Science.gov (United States)

Singh, Ashish Kumar; Patil, Balu; Hoffmann, Niklas; Saltonstall, Brooks; Doddamani, Mrityunjay; Gupta, Nikhil

2018-03-01

This work focuses on developing filaments of high-density polyethylene (HDPE) and their hollow particle-filled syntactic foams for commercial three-dimensional (3D) printers based on fused filament fabrication technology. Hollow fly-ash cenospheres were blended by 40 wt.% in a HDPE matrix to produce syntactic foam (HDPE40) filaments. Further, the recycling potential was studied by pelletizing the filaments again to extrude twice (2×) and three times (3×). The filaments were tensile tested at 10-4 s-1, 10-3 s-1, and 10-2 s-1 strain rates. HDPE40 filaments show an increasing trend in modulus and strength with the strain rate. Higher density and modulus were noticed for 2× filaments compared to 1× filaments because of the crushing of some cenospheres in the extrusion cycle. However, 2× and 3× filament densities are nearly the same, showing potential for recycling them. The filaments show better properties than the same materials processed by conventional injection molding. Micro-CT scans show a uniform dispersion of cenospheres in all filaments.

Mandating nutrient menu labeling in restaurants: potential public health benefits.

Science.gov (United States)

Stran, Kimberly A; Turner, Lori W; Knol, Linda

2013-03-01

Many Americans have replaced home-cooked meals with fast food and restaurants meals. This contributes to increased incidences of overweight and obesity. Implementing policies that require restaurants to disclose nutrition information has the potential to improve nutrition knowledge and food behaviors. The purpose of this paper was to examine the potential health benefits of nutrient menu labeling in restaurants, the progress of this legislation and to provide results regarding the implementation of these policies. Data sources were obtained from a search of multiple databases including PubMed, Science Direct, Academic Search Premier, and Google Scholar. Study inclusion criteria were publication in the past ten years, obesity prevention, and utilization of nutrition labeling on menus in restaurants. The initial policies to provide consumers with nutrition information in restaurant settings began at the state levels in 2006. These laws demonstrated success, other states followed, and a national law was passed and is being implemented. Mandating nutrient menu disclosure has the potential to influence a large number of people; this legislation has the opportunity to impact Americans who dine at a fast food or chain restaurant. Given the growing obesity epidemic, continued research is necessary to gauge the effectiveness of this new law and its effects on the health status of the American people.

Recycling Biowaste – Human and Animal Health Problems

Directory of Open Access Journals (Sweden)

Albihn Ann

2002-03-01

Full Text Available Biowaste from the food chain is of potential benefit to use in agriculture. Agriculture in general and organic farming in particular needs alternative plant nutrients. However, the quality concerning hygiene and soil contaminants must be assured. This recycling has to be regulated in a way that harmful effects on soil, vegetation, animals and man are prevented. The problems with heavy metals and organic contaminants have been focused on. Still, maximum threshold values are continuously discussed to avoid an increase of soil concentrations. The effect on the ecosystems of residues from use of medicines needs further attention. There is also a risk for a spread of antibiotic resistant micro-organisms in the environment and then to animals and man. Infectious diseases may be spread from biowaste and new routes of disease transmission between animals and humans can be created. Zoonotic diseases in this context play a central role. Pathogens recently introduced to a country may be further spread when biowaste is recycled. The very good health status of domestic animals in the Nordic countries may then quickly change. The quality of biowaste is of enormous importance if biowaste is to gain general acceptance for agricultural use, especially for organic production. A balance needs to be maintained between risk and advantage for its use.

Potentials and management of nutrient status of soils of Ikwuano ...

African Journals Online (AJOL)

The study was carried out to evaluate the nutrient status of the nine farming zones of Ikwuano local government Area of Abia State, to quantify in relation to their cassava crop production potentials. Free survey method was applied in a reconnaissance soil survey to collect soil samples at 0-30cm depth. Nine samples were ...

Assessment of the recycling potential of fresh concrete waste using a factorial design of experiments.

Science.gov (United States)

Correia, S L; Souza, F L; Dienstmann, G; Segadães, A M

2009-11-01

Recycling of industrial wastes and by-products can help reduce the cost of waste treatment prior to disposal and eventually preserve natural resources and energy. To assess the recycling potential of a given waste, it is important to select a tool capable of giving clear indications either way, with the least time and work consumption, as is the case of modelling the system properties using the results obtained from statistical design of experiments. In this work, the aggregate reclaimed from the mud that results from washout and cleaning operations of fresh concrete mixer trucks (fresh concrete waste, FCW) was recycled into new concrete with various water/cement ratios, as replacement of natural fine aggregates. A 3(2) factorial design of experiments was used to model fresh concrete consistency index and hardened concrete water absorption and 7- and 28-day compressive strength, as functions of FCW content and water/cement ratio, and the resulting regression equations and contour plots were validated with confirmation experiments. The results showed that the fresh concrete workability worsened with the increase in FCW content but the water absorption (5-10 wt.%), 7-day compressive strength (26-36 MPa) and 28-day compressive strength (32-44 MPa) remained within the specified ranges, thus demonstrating that the aggregate reclaimed from FCW can be recycled into new concrete mixtures with lower natural aggregate content.

Experimental investigation of the quality characteristics of agricultural plastic wastes regarding their recycling and energy recovery potential.

Science.gov (United States)

Briassoulis, D; Hiskakis, M; Babou, E; Antiohos, S K; Papadi, C

2012-06-01

A holistic environmentally sound waste management scheme that transforms agricultural plastic waste (APW) streams into labelled guaranteed quality commodities freely traded in open market has been developed by the European research project LabelAgriWaste. The APW quality is defined by the APW material requirements, translated to technical specifications, for recycling or energy recovery. The present work investigates the characteristics of the APW quality and the key factors affecting it from the introduction of the virgin product to the market to the APW stream reaching the disposer. Samples of APW from different countries were traced from their application to the field through their storage phase and transportation to the final destination. The test results showed that the majority of APW retained their mechanical properties after their use preserving a "very good quality" for recycling in terms of degradation. The degree of soil contamination concerning the APW recycling and energy recovery potential fluctuates depending on the agricultural plastic category and application. The chlorine and heavy metal content of the tested APW materials was much lower than the maximum acceptable limits for their potential use in cement industries. Copyright © 2012 Elsevier Ltd. All rights reserved.

Recycling Mentors: an intergenerational, service-learning program to promote recycling and environmental awareness.

Science.gov (United States)

D'abundo, Michelle L; Fugate-Whitlock, Elizabeth I; Fiala, Kelly A

2011-01-01

The purpose of Recycling Mentors was to implement an intergenerational, service-learning program focused on promoting recycling and environmental awareness among students enrolled in Community Health (HEA 301) and Current Issues in Gerontology (GRN 440/540) and adults older than 60 years. Recycling Mentors was conducted in New Hanover County (NHC), North Carolina, where a moderate climate and coastal location attracts many tourists, retirees, and college students. A community like NHC is a good place to implement service-learning that educates both students and older adults about the benefits of recycling to individual health and the environment. During the Fall 2009 semester, undergraduate and graduate students completed institutional review board training and then conducted the program with older adults. The education component of Recycling Mentors included a pre/post survey, brochure, and scheduled visits. Overall, Recycling Mentors was positive service-learning experience with students identifying salient outcomes such as learning about recycling and the environment and working with older adults. In addition, teaching the education component of Recycling Mentors was good practice for students who will be the future health professionals. While service-learning and environmentally themed projects are common, a program that combines the 2 like Recycling Mentors is unique and has the potential to motivate individual change while positively impacting the local community and the environment.

Measurement of broiler litter production rates and nutrient content using recycled litter.

Science.gov (United States)

Coufal, C D; Chavez, C; Niemeyer, P R; Carey, J B

2006-03-01

It is important for broiler producers to know litter production rates and litter nutrient content when developing nutrient management plans. Estimation of broiler litter production varies widely in the literature due to factors such as geographical region, type of housing, size of broiler produced, and number of flocks reared on the same litter. Published data for N, P, and K content are also highly variable. In addition, few data are available regarding the rate of production, characteristics, and nutrient content of caked litter (cake). In this study, 18 consecutive flocks of broilers were reared on the same litter in experimental pens under simulated commercial conditions. The mass of litter and cake produced was measured after each flock. Samples of all litter materials were analyzed for pH, moisture, N, P, and K. Average litter and cake moisture content were 26.4 and 46.9%, respectively. Significant variation in litter and cake nutrient content was observed and can largely be attributed to ambient temperature differences. Average litter, cake, and total litter (litter plus cake) production rates were 153.3, 74.8, and 228.2 g of dry litter material per kg of live broiler weight (g/kg) per flock, respectively. Significant variation in litter production rates among flocks was also observed. Cumulative litter, cake, and total litter production rates after 18 flocks were 170.3, 78.7, and 249.0 g/kg, respectively. The data produced from this research can be used by broiler producers to estimate broiler litter and cake production and the nutrient content of these materials.

Advances in the understanding of nutrient dynamics and management in UK agriculture

Energy Technology Data Exchange (ETDEWEB)

Dungait, Jennifer A.J., E-mail: jennifer.dungait@rothamsted.ac.uk [Department of Sustainable Soils and Grassland Systems, Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB (United Kingdom); Cardenas, Laura M.; Blackwell, Martin S.A.; Wu, Lianhai [Department of Sustainable Soils and Grassland Systems, Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB (United Kingdom); Withers, Paul J.A. [School of Environment, Natural Resources and Geography, Bangor University, Bangor, Gwynedd, LL57 2UW (United Kingdom); Chadwick, David R.; Bol, Roland; Murray, Philip J. [Department of Sustainable Soils and Grassland Systems, Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB (United Kingdom); Macdonald, Andrew J.; Whitmore, Andrew P. [Department of Sustainable Soils and Grassland Systems, Rothamsted Research, Harpenden, Hertfordshire, AL5 2LQ (United Kingdom); Goulding, Keith W.T. [Department of Sustainable Soils and Grassland Systems, Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB (United Kingdom); Department of Sustainable Soils and Grassland Systems, Rothamsted Research, Harpenden, Hertfordshire, AL5 2LQ (United Kingdom)

2012-09-15

Current research on macronutrient cycling in UK agricultural systems aims to optimise soil and nutrient management for improved agricultural production and minimise effects on the environment and provision of ecosystem services. Nutrient use inefficiencies can cause environmental pollution through the release of greenhouse gases into the atmosphere and of soluble and particulate forms of N, P and carbon (C) in leachate and run-off into watercourses. Improving nutrient use efficiencies in agriculture calls for the development of sustainable nutrient management strategies: more efficient use of mineral fertilisers, increased recovery and recycling of waste nutrients, and, better exploitation of the substantial inorganic and organic reserves of nutrients in the soil. Long-term field experimentation in the UK has provided key knowledge of the main nutrient transformations in agricultural soils. Emerging analytical technologies, especially stable isotope labelling, that better characterise macronutrient forms and bioavailability and improve the quantification of the complex relationships between the macronutrients in soils at the molecular scale, are augmenting this knowledge by revealing the underlying processes. The challenge for the future is to determine the relationships between the dynamics of N, P and C across scales, which will require both new modelling approaches and integrated approaches to macronutrient cycling. -- Highlights: Black-Right-Pointing-Pointer Major advances in the knowledge of macronutrient cycling in agricultural soils are reviewed in the context of management. Black-Right-Pointing-Pointer Novel analytical techniques and innovative modelling approaches that enhance understanding of nutrient cycling are explored. Black-Right-Pointing-Pointer Knowledge gaps are identified, and the potential to improve comprehension of the integrated nutrient cycles is considered.

Nutrient management for rice production

International Nuclear Information System (INIS)

Khan, A.R.; Chandra, D.; Nanda, P.; Singh, S.S.; Singh, S.R.; Ghorai, A.K.

2002-06-01

The nutrient removed by the crops far exceeds the amounts replenished through fertilizer, causing a much greater strain on the native soil reserves. The situation is further aggravated in countries like India, where sub-optimal fertilizer used by the farmers is a common phenomenon rather than an exception. The total consumption of nutrients of all crops in India, even though reached 15 million tons in 1997, remains much below the estimated nutrient removal of 25 million tons (Swarup and Goneshamurthy, 1998). The gap between nutrient removal supplied through fertilizer has widened further in 2000 to 34 million tons of plant nutrients from the soil against an estimated fertilizer availability of 18 million tons (Singh and Dwivedi, 1996). Nitrogen is the nutrient which limits the most the rice production worldwide. In Asia, where more than 90 percent of the world's rice is produced, about 60 percent of the N fertilizer consumed is used on rice (Stangel and De Dutta, 1985). Conjunctive use of organic material along with fertilizer has been proved an efficient source of nitrogen. Organic residue recycling is becoming an increasingly important aspect of environmentally sound sustainable agriculture. Returning residues like green manure to the soil is necessary for maintaining soil organic matter, which is important for favourable soil structure, soil water retention and soil microbial flora and fauna activities. Use of organic manures in conjunction or as an alternative to chemical fertilizer is receiving attention. Green manure, addition to some extent, helps not only in enhancing the yield but also in improving the physical and chemical nature of soils. The excessive application of chemical fertilizers made it imperative that a part of inorganic fertilizer may be substituted with the recycling of organic wastes. Organic manure has been recorded to enhance the efficiency and reduce the requirement of chemical fertilizers. Partial nitrogen substitution through organic

What can recycling in thermal reactors accomplish?

International Nuclear Information System (INIS)

Piet, Steven J.; Matthern, Gretchen E.; Jacobson, Jacob J.

2007-01-01

Thermal recycle provides several potential benefits when used as stop-gap, mixed, or backup recycling to recycling in fast reactors. These three roles involve a mixture of thermal and fast recycling; fast reactors are required to some degree at some time. Stop-gap uses thermal reactors only until fast reactors are adequately deployed and until any thermal-recycle-only facilities have met their economic lifetime. Mixed uses thermal and fast reactors symbiotically for an extended period of time. Backup uses thermal reactors only if problems later develop in the fast reactor portion of a recycling system. Thermal recycle can also provide benefits when used as pure thermal recycling, with no intention to use fast reactors. However, long term, the pure thermal recycling approach is inadequate to meet several objectives. (authors)

What can Recycling in Thermal Reactors Accomplish?

International Nuclear Information System (INIS)

Steven Piet; Gretchen E. Matthern; Jacob J. Jacobson

2007-01-01

Thermal recycle provides several potential benefits when used as stop-gap, mixed, or backup recycling to recycling in fast reactors. These three roles involve a mixture of thermal and fast recycling; fast reactors are required to some degree at some time. Stop-gap uses thermal reactors only until fast reactors are adequately deployed and until any thermal-recycle-only facilities have met their economic lifetime. Mixed uses thermal and fast reactors symbiotically for an extended period of time. Backup uses thermal reactors only if problems later develop in the fast reactor portion of a recycling system. Thermal recycle can also provide benefits when used as pure thermal recycling, with no intention to use fast reactors. However, long term, the pure thermal recycling approach is inadequate to meet several objectives

Recycling of reprocessed uranium

International Nuclear Information System (INIS)

Randl, R.P.

1987-01-01

Since nuclear power was first exploited in the Federal Republic of Germany, the philosophy underlying the strategy of the nuclear fuel cycle has been to make optimum use of the resource potential of recovered uranium and plutonium within a closed fuel cycle. Apart from the weighty argument of reprocessing being an important step in the treatment and disposal of radioactive wastes, permitting their optimum ecological conditioning after the reprocessing step and subsequent storage underground, another argument that, no doubt, carried weight was the possibility of reducing the demand of power plants for natural uranium. In recent years, strategies of recycling have emerged for reprocessed uranium. If that energy potential, too, is to be exploited by thermal recycling, it is appropriate to choose a slightly different method of recycling from the one for plutonium. While the first generation of reprocessed uranium fuel recycled in the reactor cuts down natural uranium requirement by some 15%, the recycling of a second generation of reprocessed, once more enriched uranium fuel helps only to save a further three per cent of natural uranium. Uranium of the second generation already carries uranium-232 isotope, causing production disturbances, and uranium-236 isotope, causing disturbances of the neutron balance in the reactor, in such amounts as to make further fabrication of uranium fuel elements inexpedient, even after mixing with natural uranium feed. (orig./UA) [de

Nutrients in estuaries — An overview and the potential impacts of climate change

International Nuclear Information System (INIS)

Statham, Peter J.

2012-01-01

The fate and cycling of macronutrients introduced into estuaries depend upon a range of interlinked processes. Hydrodynamics and morphology in combination with freshwater inflow control the freshwater flushing time, and the timescale for biogeochemical processes to operate that include microbial activity, particle-dissolved phase interactions, and benthic exchanges. In some systems atmospheric inputs and exchanges with coastal waters can also be important. Climate change will affect nutrient inputs and behaviour through modifications to temperature, wind patterns, the hydrological cycle, and sea level rise. Resulting impacts include: 1) inundation of freshwater systems 2) changes in stratification, flushing times and phytoplankton productivity 3) increased coastal storm activity 4) changes in species and ecosystem function. A combination of continuing high inputs of nutrients through human activity and climate change is anticipated to lead to enhanced eutrophication in the future. The most obvious impacts of increasing global temperature will be in sub-arctic systems where permafrost zones will be reduced in combination with enhanced inputs from glacial systems. Improved process understanding in several key areas including cycling of organic N and P, benthic exchanges, resuspension, impact of bio-irrigation, particle interactions, submarine groundwater discharges, and rates and magnitude of bacterially-driven recycling processes, is needed. Development of high frequency in situ nutrient analysis systems will provide data to improve predictive models that need to incorporate a wider variety of key factors, although the complexity of estuarine systems makes such modelling a challenge. However, overall a more holistic approach is needed to effectively understand, predict and manage the impact of macronutrients on estuaries. -- Highlights: ► Estuarine macronutrient behaviour defined by both physical and biogeochemical processes. ► Climate change impacts: sea level

Enhanced biological stabilization of heavy metals in sediment using immobilized sulfate reducing bacteria beads with inner cohesive nutrient

Energy Technology Data Exchange (ETDEWEB)

Li, Xin, E-mail: hgxlixin@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Dai, Lihua; Zhang, Chang; Zeng, Guangming; Liu, Yunguo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Zhou, Chen [Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University (United States); Xu, Weihua; Wu, Youe; Tang, Xinquan; Liu, Wei; Lan, Shiming [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China)

2017-02-15

Highlights: • Nutrient beads of immobilized SRB were more effective in transforming heavy metals into the more stable bound phases. • Inner cohesive nutrient effectively promoted the stabilization process of heavy metals. • The excellent removal efficiencies of Cu, Zn, Pb and Cd were 76.3%, 95.6%, 100% and 91.2%, respectively. • Easy to recycle and avoid secondary pollution. - Abstract: A series of experiments were conducted for treating heavy metals contaminated sediments sampled from Xiangjiang River, which combined polyvinyl alcohol (PVA) and immobilized sulfate reducing bacteria (SRB) into beads. The sodium lactate was served as the inner cohesive nutrient. Coupling the activity of the SRB with PVA, along with the porous structure and huge specific surface area, provided a convenient channel for the transmission of matter and protected the cells against the toxicity of metals. This paper systematically investigated the stability of Cu, Zn, Pb and Cd and its mechanisms. The results revealed the performance of leaching toxicity was lower and the removal efficiencies of Cu, Zn, Pb and Cd were 76.3%, 95.6%, 100% and 91.2%, respectively. Recycling experiments showed the beads could be reused 5 times with superbly efficiency. These results were also confirmed by continuous extraction at the optimal conditions. Furthermore, X-ray diffraction (XRD) and energy-dispersive spectra (EDS) analysis indicated the heavy metals could be transformed into stable crystal texture. The stabilization of heavy metals was attributed to the carbonyl and acyl amino groups. Results presented that immobilized bacteria with inner nutrient were potentially and practically applied to multi-heavy-metal-contamination sediment.

Effects of changes in nutrient loading and composition on hypoxia dynamics and internal nutrient cycling of a stratified coastal lagoon

Science.gov (United States)

Zhu, Yafei; McCowan, Andrew; Cook, Perran L. M.

2017-10-01

The effects of changes in catchment nutrient loading and composition on the phytoplankton dynamics, development of hypoxia and internal nutrient dynamics in a stratified coastal lagoon system (the Gippsland Lakes) were investigated using a 3-D coupled hydrodynamic biogeochemical water quality model. The study showed that primary production was equally sensitive to changed dissolved inorganic and particulate organic nitrogen loads, highlighting the need for a better understanding of particulate organic matter bioavailability. Stratification and sediment carbon enrichment were the main drivers for the hypoxia and subsequent sediment phosphorus release in Lake King. High primary production stimulated by large nitrogen loading brought on by a winter flood contributed almost all the sediment carbon deposition (as opposed to catchment loads), which was ultimately responsible for summer bottom-water hypoxia. Interestingly, internal recycling of phosphorus was more sensitive to changed nitrogen loads than total phosphorus loads, highlighting the potential importance of nitrogen loads exerting a control over systems that become phosphorus limited (such as during summer nitrogen-fixing blooms of cyanobacteria). Therefore, the current study highlighted the need to reduce both total nitrogen and total phosphorus for water quality improvement in estuarine systems.

Effects of changes in nutrient loading and composition on hypoxia dynamics and internal nutrient cycling of a stratified coastal lagoon

Directory of Open Access Journals (Sweden)

Y. Zhu

2017-10-01

Full Text Available The effects of changes in catchment nutrient loading and composition on the phytoplankton dynamics, development of hypoxia and internal nutrient dynamics in a stratified coastal lagoon system (the Gippsland Lakes were investigated using a 3-D coupled hydrodynamic biogeochemical water quality model. The study showed that primary production was equally sensitive to changed dissolved inorganic and particulate organic nitrogen loads, highlighting the need for a better understanding of particulate organic matter bioavailability. Stratification and sediment carbon enrichment were the main drivers for the hypoxia and subsequent sediment phosphorus release in Lake King. High primary production stimulated by large nitrogen loading brought on by a winter flood contributed almost all the sediment carbon deposition (as opposed to catchment loads, which was ultimately responsible for summer bottom-water hypoxia. Interestingly, internal recycling of phosphorus was more sensitive to changed nitrogen loads than total phosphorus loads, highlighting the potential importance of nitrogen loads exerting a control over systems that become phosphorus limited (such as during summer nitrogen-fixing blooms of cyanobacteria. Therefore, the current study highlighted the need to reduce both total nitrogen and total phosphorus for water quality improvement in estuarine systems.

Reusable Nanocomposite Membranes for the Selective Recovery of Nutrients in Space, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Through the STTR program, NanoSonic and Virginia Tech will create low-cost, reusable membranes that selectively capture and recycle nutrients (e.g., N, P, K) from...

Auditing Operating Room Recycling: A Management Case Report.

Science.gov (United States)

McGain, Forbes; Jarosz, Katherine Maria; Nguyen, Martin Ngoc Hoai Huong; Bates, Samantha; O'Shea, Catherine Jane

2015-08-01

Much waste arises from operating rooms (ORs). We estimated the practical and financial feasibility of an OR recycling program, weighing all waste from 6 ORs in Melbourne, Australia. Over 1 week, 237 operations produced 1265 kg in total: general waste 570 kg (45%), infectious waste 410 kg (32%), and recyclables 285 kg (23%). The achieved recycling had no infectious contamination. The achieved recycling/potential recycling rate was 285 kg/517 kg (55%). The average waste disposal costs were similar for general waste and recycling. OR recycling rates of 20%-25% total waste were achievable without compromising infection control or financial constraints.

Water use and its recycling in microalgae cultivation for biofuel application.

Science.gov (United States)

Farooq, Wasif; Suh, William I; Park, Min S; Yang, Ji-Won

2015-05-01

Microalgal biofuels are not yet economically viable due to high material and energy costs associated with production process. Microalgae cultivation is a water-intensive process compared to other downstream processes for biodiesel production. Various studies found that the production of 1 L of microalgal biodiesel requires approximately 3000 L of water. Water recycling in microalgae cultivation is desirable not only to reduce the water demand, but it also improves the economic feasibility of algal biofuels as due to nutrients and energy savings. This review highlights recently published studies on microalgae water demand and water recycling in microalgae cultivation. Strategies to reduce water footprint for microalgal cultivation, advantages and disadvantages of water recycling, and approaches to mitigate the negative effects of water reuse within the context of water and energy saving are also discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of changes in broth composition on Chlorella vulgaris cultivation in a membrane photobioreactor (MPBR) with permeate recycle.

Science.gov (United States)

Discart, V; Bilad, M R; Marbelia, L; Vankelecom, I F J

2014-01-01

A membrane photobioreactor (MPBR) is a proven and very useful concept in which microalgae can be simultaneously cultivated and pre-harvested. However, the behavior with respect to accumulation of algogenic organic matter, including transparent exopolymeric particles (TEPs), counter ions and unassimilated nutrients due to the recycling of the medium is still unclear, even though the understanding of this behavior is essential for the optimization of microalgae processing. Therefore, the dynamics of these compounds, especially TEPs, during coupled cultivation and harvesting of Chlorella vulgaris in an MPBR with permeate recycle are addressed in this study. Results show that TEPs are secreted during algae cell growth, and that their presence is thus inevitable. In the system with permeate recycle, substances such as counter ions and unassimilated nutrients get accumulated in the system. This was proven to limit the algae growth, together with the occurrence of bioflocculation due to an increasing broth pH. Copyright © 2013 Elsevier Ltd. All rights reserved.

The feasibility of recycling contaminated concrete

International Nuclear Information System (INIS)

Ayers, K.W.; Corroon, W.; Parker, F.L.

1999-01-01

The changing mission of the Department of Energy along with the aging of many of its facilities has resulted in renewed emphasis on decontaminating and decommissioning surplus structures. Currently DOE is decontaminating some concrete and sending the clean material to C and D disposal facilities. In other instance, DOE is sending contaminated concrete to LLW disposal facilities. This paper examines the economic feasibility of decontaminating the concrete and recycling the rubble as clean aggregate. A probabilistic cost model was used to examine six potential recycling and disposal scenarios. The model predicted potential costs saving across the DOE complex of nearly one billion dollars. The ability of local markets to assimilate the recycled material was estimated for Washington, Idaho, Tennessee, New Mexico, and South Carolina. The relationships between a number of the economic model's variables were examined to develop operating ranges for initial managerial evaluation of recycling

Management and recycling of electronic waste

International Nuclear Information System (INIS)

Tanskanen, Pia

2013-01-01

Waste electrical and electronic equipment (WEEE) is one of the largest growing waste streams globally. Hence, for a sustainable environment and the economic recovery of valuable material for reuse, the efficient recycling of electronic scrap has been rendered indispensable, and must still be regarded as a major challenge for today’s society. In contrast to the well-established recycling of metallic scrap, it is much more complicated to recycle electronics products which have reached the end of their life as they contain many different types of material types integrated into each other. As illustrated primarily for the recycling of mobile phones, the efficient recycling of WEEE is not only a challenge for the recycling industry; it is also often a question of as-yet insufficient collection infrastructures and poor collection efficiencies, and a considerable lack of the consumer’s awareness for the potential of recycling electronics for the benefit of the environment, as well as for savings in energy and raw materials

Effects of feeding wheat or corn-wheat dried distillers grains with solubles in low- or high-crude protein diets on ruminal function, omasal nutrient flows, urea-N recycling, and performance in cows.

Science.gov (United States)

Chibisa, G E; Mutsvangwa, T

2013-10-01

A study was conducted to determine the effects of including either wheat-based (W-DDGS) or corn-wheat blend (B-DDGS) dried distillers grains with solubles as the major protein source in low- or high-crude protein (CP) diets fed to dairy cows on ruminal function, microbial protein synthesis, omasal nutrient flows, urea-N recycling, and milk production. Eight lactating Holstein cows (768.5 ± 57.7 kg of body weight; 109.5 ± 40.0 d in milk) were used in a replicated 4 × 4 Latin square design with 28-d periods (18d of dietary adaptation and 10d of measurements) and a 2 × 2 factorial arrangement of dietary treatments. Four cows in one Latin square were ruminally cannulated for the measurement of ruminal fermentation characteristics, microbial protein synthesis, urea-N recycling kinetics, and omasal nutrient flow. The treatment factors were type of distillers co-product (W-DDGS vs. B-DDGS) and dietary CP content [15.2 vs. 17.3%; dry matter (DM) basis]. The B-DDGS was produced from a mixture of 15% wheat and 85% corn grain. All diets were formulated to contain 10% W-DDGS or B-DDGS on a DM basis. No diet effect was observed on DM intake. Yields of milk, fat, protein, and lactose, and plasma urea-N and milk urea-N concentrations were lower in cows fed the low-CP compared with those fed the high-CP diet. Although feeding B-DDGS tended to reduce ruminal ammonia-N (NH3-N) concentration compared with feeding W-DDGS (9.3 vs. 10.5mg/dL), no differences were observed in plasma urea-N and milk urea-N concentrations. Additionally, dietary inclusion of B-DDGS compared with W-DDGS did not affect rumen-degradable protein supply, omasal flows of total N, microbial nonammonia N (NAN), rumen-undegradable protein, and total NAN, or urea-N recycling kinetics and milk production. However, cows fed the low-CP diet had lower N intake, rumen-degradable protein supply, ruminal NH3-N concentration, and omasal flows of N, microbial NAN, and total NAN compared with those fed the high-CP diet

Integration of Demilitarization Contractors and Recyclers - Collateral Benefits of On-Site Training of Recyclers

Science.gov (United States)

2010-07-01

item Spherical? Wedge Shaped? Cylindrical? These items are potentially very dangerous 29 Spherical = Not Good If found in a recycling yard, don’t...touch! Call 9-1-1 BLU-63 30 Wedge Shape = Not Good If found in a recycling yard, don’t touch! Call 9-1-1 M72M43 31 Cylindrical = Not Good If found in a

Potential of diatom consortium developed by nutrient enrichment for biodiesel production and simultaneous nutrient removal from waste water

Directory of Open Access Journals (Sweden)

Thomas Kiran Marella

2018-05-01

Full Text Available Because of the decreasing fossil fuel supply and increasing greenhouse gas (GHG emissions, microalgae have been identified as a viable and sustainable feedstock for biofuel production. The major effect of the release of wastewater rich in organic compounds has led to the eutrophication of freshwater ecosystems. A combined approach of freshwater diatom cultivation with urban sewage water treatment is a promising solution for nutrient removal and biofuel production. In this study, urban wastewater from eutrophic Hussain Sagar Lake was used to cultivate a diatom algae consortium, and the effects of silica and trace metal enrichment on growth, nutrient removal, and lipid production were evaluated. The nano-silica-based micronutrient mixture Nualgi containing Si, Fe, and metal ions was used to optimize diatom growth. Respectively, N and P reductions of 95.1% and 88.9%, COD and BOD reductions of 91% and 51% with a biomass yield of 122.5 mg L−1 day−1 and lipid productivity of 37 mg L−1 day−1 were observed for cultures grown in waste water using Nualgi. Fatty acid profiles revealed 13 different fatty acids with slight differences in their percentage of dry cell weight (DCW depending on enrichment level. These results demonstrate the potential of diatom algae grown in wastewater to produce feedstock for renewable biodiesel production. Enhanced carbon and excess nutrient utilization makes diatoms ideal candidates for co-processes such as CO2 sequestration, biodiesel production, and wastewater phycoremediation. Keywords: Micro algae, Diatom, Biodiesel, Nualgi, Nutrient removal, Wastewater

A Review on Recycling of Sunflower Residue for Sustaining Soil Health

Directory of Open Access Journals (Sweden)

Subhash Babu

2014-01-01

Full Text Available Modern agriculture is now at the crossroads ecologically, economically, technologically, and socially due to soil degradation. Critical analysis of available information shows that problems of degradation of soil health are caused due to imbalanced, inadequate and promacronutrient fertilizer use, inadequate use or no use of organic manures and crop residues, and less use of good quality biofertilizers. Although sizeable amount of crop residues and manure is produced in farms, it is becoming increasingly complex to recycle nutrients, even within agricultural systems. Therefore, there is a need to use all available sources of nutrients to maintain the productivity and fertility at a required level. Among the available organic sources of plant nutrients, crop residue is one of the most important sources for supplying nutrients to the crop and for improving soil health. Sunflower is a nontraditional oil seed crop produced in huge amount of crop residue. This much amount of crop residues is neither used as feed for livestock nor suitable for fuel due to low energy value per unit mass. However, its residue contains major plant nutrients in the range from 0.45 to 0.60% N, 0.15 to 0.22% P, and 1.80 to 1.94% K along with secondary and micronutrients, so recycling of its residue in the soil may be one of the best alternative practices for replenishing the depleted soil fertility and improving the physical, chemical, and biological properties of the soil in the present era of production. However, some researchers have reported allelopathic effects of sunflower residue on different crops. So, selection of suitable crops and management practices may play an important role to manage the sunflower residue at field level.

Regular Recycling of Wood Ash to Prevent Waste Production (RecAsh). Technical Final Report

Energy Technology Data Exchange (ETDEWEB)

Andersson, Lars E-mail: lars.t.andersson@skogsstyreslen.se

2007-03-15

At present, the extraction of harvest residues is predicted to increase in Sweden and Finland. As an effect of the intensified harvesting, the export of nutrients and acid buffering substances from the growth site is also increased. Wood ash could be used to compensate forest soils for such losses. Most wood fuel ash is today often deposited in landfills. If the wood ash is recycled, wood energy is produced without any significant waste production. Ash recycling would therefore contribute to decreasing the production of waste, and to maintaining the chemical quality of forest waters and biological productivity of forest soils in the long term. The project has developed, analysed and demonstrated two regular ash-recycling systems. It has also distributed knowledge gathered about motives for ash recycling as well as technical and administrative solutions through a range of media (handbooks, workshops, field demonstrations, reports, web page and information videos). Hopefully, the project will contribute to decreasing waste problems related to bio-energy production in the EU at large. The project has been organised as a separate structure at the beneficiary and divided in four geographically defined subprojects, one in Finland and three in Sweden (Central Sweden, Northern Sweden, and South-western Sweden). The work in each subproject has been lead by a subproject leader. Each subproject has organised a regional reference group. A project steering committee has been established consisting of senior officials from all concerned partners. The project had nine main tasks with the following main expected deliverables and output: 1. Development of two complete full-scale ash-recycling systems; 2. Production of handbooks of the ash recycling system; 3. Ash classification study to support national actions for recommendations; 4. Organise regional demonstrations of various technical options for ash treatment and spreading; 5. Organise national seminars and demonstrations of

Impacts of policy and market incentives for solid waste recycling in Dhaka, Bangladesh

International Nuclear Information System (INIS)

Matter, Anne; Ahsan, Mehedi; Marbach, Michelle; Zurbrügg, Christian

2015-01-01

Highlights: • Bangladesh’s industry and population are growing rapidly, producing more urban waste. • Recycling reduces the solid waste management burden of Municipalities. • A wide array of informal and formal actors is involved in collection and recycling. • Demand for recycled materials and renewable energy creates market incentives. • Policy incentives exist, but they only reach the formal industry. - Abstract: Solid waste mismanagement in Dhaka, Bangladesh, illustrates a well-known market failure which can be summarized as: waste is a resource in the wrong place. Inorganic materials such as plastic or paper can be used to feed the demand for recycled materials in the industrial sector. Organic materials can be converted and used in the nutrient-starved agricultural sector which is currently heavily depending on chemical fertilizers. They are also a feedstock to generate renewable energy in the form of biogas for this energy-starved country relying on diminishing natural gas reserves and increasing import of coal. Reality however does not capitalize on this potential; instead the waste is a burden for municipal authorities who spend large portions of their budgets attempting to transport it out of the city for discharge into landfills. The major part of these materials still remains uncollected in the residential areas and is discarded indiscriminately in open spaces, polluting the residents’ living environment including water, soil and air resources, in the city and beyond. Bangladeshi authorities have, to some extent, recognized this market failure and have developed policies to encourage the development of waste recycling activities. It is also important to note that this market failure is only partial: a large, mostly informal recycling sector has developed in Bangladesh, focusing on inorganic recyclables of market value. The fact that this sector remains largely informal means that these actors perceive significant barriers to formalization

Impacts of policy and market incentives for solid waste recycling in Dhaka, Bangladesh

Energy Technology Data Exchange (ETDEWEB)

Matter, Anne [Eawag: Swiss Federal Institute of Aquatic Science and Technology, Department of Water and Sanitation in Developing Countries (Sandec), Überlandstrasse 133, P.O. Box 611, 8600 Dübendorf (Switzerland); Swisscontact: Swiss Foundation for Technical Cooperation, South Asian Regional Office, House No. 19, Road No. 11, Baridhara, Dhaka 1212 (Bangladesh); Ahsan, Mehedi [KfW: Development Bank for Germany, Bangladesh Office, House 10/C, Road 90, Gulshan 2, Dhaka 1212 (Bangladesh); Marbach, Michelle [NADEL: Center for Development and Cooperation, Swiss Federal Institute of Technology Zurich, Clausiusstrasse 37, 8092 Zürich (Switzerland); Zurbrügg, Christian [Eawag: Swiss Federal Institute of Aquatic Science and Technology, Department of Water and Sanitation in Developing Countries (Sandec), Überlandstrasse 133, P.O. Box 611, 8600 Dübendorf (Switzerland)

2015-05-15

Highlights: • Bangladesh’s industry and population are growing rapidly, producing more urban waste. • Recycling reduces the solid waste management burden of Municipalities. • A wide array of informal and formal actors is involved in collection and recycling. • Demand for recycled materials and renewable energy creates market incentives. • Policy incentives exist, but they only reach the formal industry. - Abstract: Solid waste mismanagement in Dhaka, Bangladesh, illustrates a well-known market failure which can be summarized as: waste is a resource in the wrong place. Inorganic materials such as plastic or paper can be used to feed the demand for recycled materials in the industrial sector. Organic materials can be converted and used in the nutrient-starved agricultural sector which is currently heavily depending on chemical fertilizers. They are also a feedstock to generate renewable energy in the form of biogas for this energy-starved country relying on diminishing natural gas reserves and increasing import of coal. Reality however does not capitalize on this potential; instead the waste is a burden for municipal authorities who spend large portions of their budgets attempting to transport it out of the city for discharge into landfills. The major part of these materials still remains uncollected in the residential areas and is discarded indiscriminately in open spaces, polluting the residents’ living environment including water, soil and air resources, in the city and beyond. Bangladeshi authorities have, to some extent, recognized this market failure and have developed policies to encourage the development of waste recycling activities. It is also important to note that this market failure is only partial: a large, mostly informal recycling sector has developed in Bangladesh, focusing on inorganic recyclables of market value. The fact that this sector remains largely informal means that these actors perceive significant barriers to formalization

Impacts of policy and market incentives for solid waste recycling in Dhaka, Bangladesh.

Science.gov (United States)

Matter, Anne; Ahsan, Mehedi; Marbach, Michelle; Zurbrügg, Christian

2015-05-01

Solid waste mismanagement in Dhaka, Bangladesh, illustrates a well-known market failure which can be summarized as: waste is a resource in the wrong place. Inorganic materials such as plastic or paper can be used to feed the demand for recycled materials in the industrial sector. Organic materials can be converted and used in the nutrient-starved agricultural sector which is currently heavily depending on chemical fertilizers. They are also a feedstock to generate renewable energy in the form of biogas for this energy-starved country relying on diminishing natural gas reserves and increasing import of coal. Reality however does not capitalize on this potential; instead the waste is a burden for municipal authorities who spend large portions of their budgets attempting to transport it out of the city for discharge into landfills. The major part of these materials still remains uncollected in the residential areas and is discarded indiscriminately in open spaces, polluting the residents' living environment including water, soil and air resources, in the city and beyond. Bangladeshi authorities have, to some extent, recognized this market failure and have developed policies to encourage the development of waste recycling activities. It is also important to note that this market failure is only partial: a large, mostly informal recycling sector has developed in Bangladesh, focusing on inorganic recyclables of market value. The fact that this sector remains largely informal means that these actors perceive significant barriers to formalization. Comparatively, the organic waste recycling sector is less driven by market mechanisms. Competition from chemical fertilizers and fossil fuels is fierce and hinders the development of market opportunities for compost and renewable energy. Nevertheless commercial production of compost and biogas from organic municipal waste is formalized and benefiting from policy incentives. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nutrient cycling in a RRIM 600 clone rubber plantation

Directory of Open Access Journals (Sweden)

Murbach Marcos Roberto

2003-01-01

Full Text Available Few reports have been presented on nutrient cycling in rubber tree plantations (Hevea brasiliensis Muell. Arg.. This experiment was carried out to evaluate: the effect of K rates on the amount of nutrients transfered to the soil in a 13-year old Hevea brasilensis RRIM 600 clone plantation, nutrient retranslocation from the leaves before falling to the soil, and nutrient loss by dry rubber export. The experiment started in 1998 and potassium was applied at the rates of 0, 40, 80 and 160 kg ha-1 of K2O under the crowns of 40 rubber trees of each plot. Literfall collectors, five per plot, were randomly distributed within the plots under the trees. The accumulated literfall was collected monthly during one year. The coagulated rubber latex from each plot was weighed, and samples were analyzed for nutrient content. Increasing K fertilization rates also increased the K content in leaf literfall. Calcium and N were the most recycled leaf nutrients to the soil via litterfall. Potassium, followed by P were the nutrients with the highest retranslocation rates. Potassium was the most exported nutrient by the harvested rubber, and this amount was higher than that transfered to the soil by the leaf literfall.

Recovery and removal of nutrients from swine wastewater by using a novel integrated reactor for struvite decomposition and recycling

Science.gov (United States)

Huang, Haiming; Xiao, Dean; Liu, Jiahui; Hou, Li; Ding, Li

2015-01-01

In the present study, struvite decomposition was performed by air stripping for ammonia release and a novel integrated reactor was designed for the simultaneous removal and recovery of total ammonia-nitrogen (TAN) and total orthophosphate (PT) from swine wastewater by internal struvite recycling. Decomposition of struvite by air stripping was found to be feasible. Without supplementation with additional magnesium and phosphate sources, the removal ratio of TAN from synthetic wastewater was maintained at >80% by recycling of the struvite decomposition product formed under optimal conditions, six times. Continuous operation of the integrated reactor indicated that approximately 91% TAN and 97% PT in the swine wastewater could be removed and recovered by the proposed recycling process with the supplementation of bittern. Economic evaluation of the proposed system showed that struvite precipitation cost can be saved by approximately 54% by adopting the proposed recycling process in comparison with no recycling method. PMID:25960246

The Potential of Improved Fallows to Improve and Conserve the Fertility of Nutrients-Depleted Soils of Western Kenya

International Nuclear Information System (INIS)

Jama, B.; Amandou, I.; Niang; Amadalo, B.; Wolf, J.; Rao, M.R.; Buresh, R.J.

1999-01-01

Maize yields are low low and declining in the densely populated highlands of Western Kenya where soils are deficient mainly in nitrogen, phosphrous and, in some areas potassium. Over the last seven years, a team of scientists from several agricultural institutions, national and international has been developing and testing on-farm soil fertility improving technologies. Improved fallows of fast-growing leguminous species appear to be one such technology that could be a more productive alternative to the commonly practiced natural fallows. Sesbania session, Crotolaria grahamiana and Tephrosia vogelii are some the promising species. In six to eight months, fallows of these species can root to N rich subsoil (0.5-2 m) below the soil surface and recycle it to the surface soil through leaf and root litter. Within this period, N sufficient for the requirements of moderate maize yields (3-4 t ha -1 ) can be recycled particular y in sites not limited by available soil P. Such fallows can also recycle sufficient K in K deficient sites. Unfortunately soils in most areas of Western Kenya are P deficient and although improved fallows can enhance the availability of soil P less available to crops, they cannot increase its supply. Under these conditions, P inputs from external sources is necessary to improve crop yields meaningfully and economically. Agronomic evaluations of inorganic P sources for maize suggests Minjingu phosphates rock can be alternative to more expensive water-soluble P sources, e.g., triple superphosphate. The need for P input and the benefits of integrating it with improved fallows in order to overcome deficiencies of other nutrients, particularly N and K is highlighted in this paper

Recycling of beverage containers in the Northwest Territories

Energy Technology Data Exchange (ETDEWEB)

1987-02-01

This study researched existing recycling systems, presented pertinent data on the beverage and transportation industries, and evaluated the potential of recycling beverage bottles and cans in the Northwest Territories. The study first describes the history and existing concepts of recycling, provides a general description of recycling methods with advantages and disadvantages, and highlights particular approaches taken by other provinces. Markets for the Northwest Territories are also discussed, including the potential of recoverable material, anticipated recovery rates, transportation to markets, and present recycling operations. Three strategies are identified for the southwest, northwest, and the eastern Region. Recycling is preferred for aluminium cans, glass beer bottles, plastic bottles, and glass wine and liquor bottles in that order. The report recommends a limited program for aluminium cans and beer bottles to begin immediately. Beer bottles should be refilled either in Alberta or the Northwestern Territories and aluminium cans should be compacted and shipped to recycling markets in southern Canada or the United States. The program should first be implemented in areas serviced by Alberta and accessible by truck or barge from Hay River. A program implementation plan is also included. 8 refs., 2 figs., 14 tabs.

Properties of biochar derived from wood and high-nutrient biomasses with the aim of agronomic and environmental benefits.

Directory of Open Access Journals (Sweden)

Rimena R Domingues

Full Text Available Biochar production and use are part of the modern agenda to recycle wastes, and to retain nutrients, pollutants, and heavy metals in the soil and to offset some greenhouse gas emissions. Biochars from wood (eucalyptus sawdust, pine bark, sugarcane bagasse, and substances rich in nutrients (coffee husk, chicken manure produced at 350, 450 and 750°C were characterized to identify agronomic and environmental benefits, which may enhance soil quality. Biochars derived from wood and sugarcane have greater potential for improving C storage in tropical soils due to a higher aromatic character, high C concentration, low H/C ratio, and FTIR spectra features as compared to nutrient-rich biochars. The high ash content associated with alkaline chemical species such as KHCO3 and CaCO3, verified by XRD analysis, made chicken manure and coffee husk biochars potential liming agents for remediating acidic soils. High Ca and K contents in chicken manure and coffee husk biomass can significantly replace conventional sources of K (mostly imported in Brazil and Ca, suggesting a high agronomic value for these biochars. High-ash biochars, such as chicken manure and coffee husk, produced at low-temperatures (350 and 450°C exhibited high CEC values, which can be considered as a potential applicable material to increase nutrient retention in soil. Therefore, the agronomic value of the biochars in this study is predominantly regulated by the nutrient richness of the biomass, but an increase in pyrolysis temperature to 750°C can strongly decrease the adsorptive capacities of chicken manure and coffee husk biochars. A diagram of the agronomic potential and environmental benefits is presented, along with some guidelines to relate biochar properties with potential agronomic and environmental uses. Based on biochar properties, research needs are identified and directions for future trials are delineated.

Impacts of soil petroleum contamination on nutrient release during litter decomposition of Hippophae rhamnoides.

Science.gov (United States)

Zhang, Xiaoxi; Liu, Zengwen; Luc, Nhu Trung; Yu, Qi; Liu, Xiaobo; Liang, Xiao

2016-03-01

Petroleum exploitation causes contamination of shrub lands close to oil wells. Soil petroleum contamination affects nutrient release during the litter decomposition of shrubs, which influences nutrient recycling and the maintenance of soil fertility. Hence, this contamination may reduce the long-term growth and stability of shrub communities and consequently, the effects of phytoremediation. Fresh foliar litter of Hippophae rhamnoides, a potential phytoremediating species, was collected for this study. The litter was placed in litterbags and then buried in different petroleum-polluted soil media (the petroleum concentrations were 15, 30, and 45 g kg(-1) dry soil, which were considered as slightly, moderately and seriously polluted soil, respectively) for a decomposition test. The impacts of petroleum contamination on the release of nutrients (including N, P, K, Cu, Zn, Fe, Mn, Ca and Mg) were assessed. The results showed that (1) after one year of decomposition, the release of all nutrients was accelerated in the slightly polluted soil. In the moderately polluted soil, P release was accelerated, while Cu, Zn and Mn release was inhibited. In the seriously polluted soil, Cu and Zn release was accelerated, while the release of the other nutrients was inhibited. (2) The effect of petroleum on nutrient release from litter differed in different periods during decomposition; this was mainly due to changes in soil microorganisms and enzymes under the stress of petroleum contamination. (3) To maintain the nutrient cycling and the soil fertility of shrub lands, H. rhamnoides is only suitable for phytoremediation of soils containing less than 30 g kg(-1) of petroleum.

Hanford recycling

Energy Technology Data Exchange (ETDEWEB)

Leonard, I.M.

1996-09-01

This paper is a study of the past and present recycling efforts on the Hanford site and options for future improvements in the recycling program. Until 1996, recycling goals were voluntarily set by the waste generators: this year, DOE has imposed goals for all its sites to accomplish by 1999. Hanford is presently meeting the voluntary site goals, but may not be able to meet all the new DOE goals without changes to the program. Most of these new DOE goals are recycling goals: * Reduce the generation of radioactive (low-level) waste from routine operations 50 percent through source reduction and recycling. * Reduce the generation of low-level mixed waste from routine operations 50 percent through source reduction and recycling. * Reduce the generation of hazardous waste from routine operations 50 percent through source reduction and recycling. * Recycle 33 percent of the sanitary waste from all operations. * Increase affirmative procurement of EPA-designated recycled items to 100 percent. The Hanford recycling program has made great strides-there has been a 98 percent increase in the amount of paper recycled since its inception in 1990. Hanford recycles paper, chemicals cardboard, tires, oil, batteries, rags, lead weights, fluorescent tubes, aerosol products, concrete, office furniture, computer software, drums, toner cartridges, and scrap metal. Many other items are recycled or reused by individual groups on a one time basis without a formal contract. Several contracts are closed-loop contracts which involve all parts of the recycle loop. Considerable savings are generated from recycling, and much more is possible with increased attention and improvements to this program. General methods for improving the recycling program to ensure that the new goals can be met are: a Contract and financial changes 0 Tracking database and methods improvements 0 Expanded recycling efforts. Specifically, the Hanford recycling program would be improved by: 0 Establishing one overall

DWPF Recycle Evaporator Simulant Tests

International Nuclear Information System (INIS)

Stone, M

2005-01-01

Testing was performed to determine the feasibility and processing characteristics of an evaporation process to reduce the volume of the recycle stream from the Defense Waste Processing Facility (DWPF). The concentrated recycle would be returned to DWPF while the overhead condensate would be transferred to the Effluent Treatment Plant. Various blends of evaporator feed were tested using simulants developed from characterization of actual recycle streams from DWPF and input from DWPF-Engineering. The simulated feed was evaporated in laboratory scale apparatus to target a 30X volume reduction. Condensate and concentrate samples from each run were analyzed and the process characteristics (foaming, scaling, etc) were visually monitored during each run. The following conclusions were made from the testing: Concentration of the ''typical'' recycle stream in DWPF by 30X was feasible. The addition of DWTT recycle streams to the typical recycle stream raises the solids content of the evaporator feed considerably and lowers the amount of concentration that can be achieved. Foaming was noted during all evaporation tests and must be addressed prior to operation of the full-scale evaporator. Tests were conducted that identified Dow Corning 2210 as an antifoam candidate that warrants further evaluation. The condensate has the potential to exceed the ETP WAC for mercury, silicon, and TOC. Controlling the amount of equipment decontamination recycle in the evaporator blend would help meet the TOC limits. The evaporator condensate will be saturated with mercury and elemental mercury will collect in the evaporator condensate collection vessel. No scaling on heating surfaces was noted during the tests, but splatter onto the walls of the evaporation vessels led to a buildup of solids. These solids were difficult to remove with 2M nitric acid. Precipitation of solids was not noted during the testing. Some of the aluminum present in the recycle streams was converted from gibbsite to

Soil fertility status and nutrients provided to spring barley (Hordeum distichon L. by pig slurry

Directory of Open Access Journals (Sweden)

Melisa Gómez-Garrido

2014-03-01

Full Text Available Nutrient recycling using pig slurry is a common agricultural practice to manage the ever-increasing amounts of wastes from the pig industry. This study was conducted in the southeast of Spain to quantify the enrichments in major (N, P, K, Mg and minor (Zn, Fe, Cu, and Mn nutrients in soils amended with D1-170 kg N ha-1 (European Union legislated dose or D2-340 kg N ha-1, and understand the influence of pig slurry on yield and nutrient uptake in two crop seasons of spring barley (Hordeum distichon L. Compared to control, D2 increased NO3--N by 11.4X to 109 mg kg-1, Olsen-P by 6.9X to 423 mg kg-1, exchange K (2.5X to 1.6 cmol+ kg-1, Mg (1.7X to 1.8 cmol+ kg-1, diethylene-triamine pentaacetic acid (DTPA-Zn (94X to 18.2 mg kg-1, and Fe (2X to 11.3 mg kg-1. Available NO3--N, Olsen-P, and DTPA-Zn have the best correlations with crop yield and nutrient uptake. These results indicate that the assessment of soil fertility status at 1-mo after pig slurry addition provides a good indicator for potential yield and uptake of barley. However, it is suggested that leachates should be monitored to effectively manage potential releases of nitrate and phosphate into the environment.

The changes of nutrient composition of piled laying hen manure and anaerobic fermentation for recycling as a dietary ingredient for ruminants.

Science.gov (United States)

Han, Tianlong; Wang, Liping; Zhang, Yanming; Zhang, Jun; Han, Dongsheng; Lv, Ning; Han, Xiaohua; Zhao, Guoqiang; Wang, Min

2018-01-15

This study investigated the changes of nutrient compositions of piled laying hen manure, detected the physical and chemical components of laying hen manure fermented by mixed strains, and analysed its application effects on feeding ruminants. The results showed that with increasing of piling time, the contents of crude protein (CP) and ether extract (EE) in laying hen manure were reduced, while the contents of crude ash (CA), calcium (Ca) and phosphorus (P) were increased. Fermentation could effectively decrease pH value, reduce Ca/P ratio, lessen the total bacterial counts, and maintain the organisms contents in laying hen manure. The results of ruminants feeding test indicated that replacing 20% diet with laying hen manure fermentation products (MFP), the weight gain and reproductive rate were respectively decreased by 9.99% and 2% compared with the control group, and the differences were not statistically significant. This technology could recycle laying hen manures as ruminant feeds, for the purpose of reducing environmental pollution and improving economic efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

Patterns in foliar nutrient resorption stoichiometry at multiple scales: controlling factors and ecosystem consequences (Invited)

Science.gov (United States)

Reed, S.; Cleveland, C. C.; Davidson, E. A.; Townsend, A. R.

2013-12-01

During leaf senescence, nutrient rich compounds are transported to other parts of the plant and this 'resorption' recycles nutrients for future growth, reducing losses of potentially limiting nutrients. Variations in leaf chemistry resulting from nutrient resorption also directly affect litter quality, in turn, regulating decomposition rates and soil nutrient availability. Here we investigated stoichiometric patterns of nitrogen (N) and phosphorus (P) resorption efficiency at multiple spatial scales. First, we assembled a global database to explore nutrient resorption among and within biomes and to examine potential relationships between resorption stoichiometry and ecosystem nutrient status. Next, we used a forest regeneration chronosequence in Brazil to assess how resorption stoichiometry linked with a suite of other nutrient cycling measures and with ideas of how nutrient limitation may change over secondary forest regrowth. Finally, we measured N:P resorption ratios of six canopy tree species in a Costa Rican tropical forest. We calculated species-specific resorption ratios and compared them with patterns in leaf litter and topsoil nutrient concentrations. At the global scale, N:P resorption ratios increased with latitude and decreased with mean annual temperature (MAT) and precipitation (MAP; P1 in latitudes >23°. Focusing on tropical sites in our global dataset we found that, despite fewer data and a restricted latitudinal range, a significant relationship between latitude and N:P resorption ratios persisted (PAmazon Basin chronosequence of regenerating forests, where previous work reported a transition from apparent N limitation in younger forests to P limitation in mature forests, we found N resorption was highest in the youngest forest, whereas P resorption was greatest in the mature forest. Over the course of succession, N resorption efficiency leveled off but P resorption continued to increase with forest age. In Costa Rica, though we found species

A Potential Waste to be Selected as Media for Metal and Nutrient Removal

Science.gov (United States)

Zayadi, N.; Othman, N.; Hamdan, R.

2016-07-01

This study describes the potential of application of cassava peel, banana peel, coconut shell, and coconut coir to be selected as metal removal while limestone and steel slag for nutrient removal. The media were characterized by X-Ray Fluorescence (XRF), Fourier Transform Infrared (FTIR), Field Emission Scanning Electron Microscopy-Energy Dispersive X-Ray (FESEM-EDX), and X-Ray Powder Diffraction (XRD). The results of XRF analysis medias show the present of calcium oxide, CaO which confirm the high efficiency in adsorbing metal ions and nutrient which is in agreement with the result of XRD. The characteristics of medias by FTIR analysis also confirmed the involvement of alcohol, carboxylic, alkanes, amines and ethers which play important role to reduce ions while FESEM-EDX indicates the porous structures of study medias. The characterization analysis highlight that cassava peel and steel slag were selected as a potential media in this study.

Evaluation of the costs and benefits of recycling radioactively contaminated scrap metal

International Nuclear Information System (INIS)

Durman, E.C.; Tsirigotis, P.; MacKinney, J.A.

1995-01-01

The U.S. Environmental Protection Agency (EPA) is evaluating the economic and technical issues associated with the potential recycling of radioactive scrap metals (RSM). These metals, usually only slightly contaminated, originate primarily from the decommissioning and decontamination (D and D) of federal facilities, licensees of the Nuclear Regulatory Commission, and certain unlicensed industries. EPA conducted a study entitled Analysis of the Potential Recycling of Department of Energy Radioactive Scrap Metal, September 6, 1994, for the U.S. Department of Energy (DOE) to provide information and tools to DOE for assessing DOE's problem with RSM from the D and D of their sites. EPA is now initiating an evaluation of RSM recycling to support a recycling regulation. Although the study prepared for DOE will provide a useful start for the regulatory analysis, additional information must be gathered to analyze the impacts of a recycling regulation that will apply to all potential generators of RSM. This paper summarizes cost-benefit issues related to an RSM recycling regulatory analysis, including: the quantity of potentially recyclable contaminated metals; costs of disposal at federal and private waste repositories; all potential environmental, health, and safety, and market impacts; and the potential for adverse effects on radio-sensitive industries. (author)

Managing Soil Biota-Mediated Decomposition and Nutrient Mineralization in Sustainable Agroecosystems

Directory of Open Access Journals (Sweden)

Joann K. Whalen

2014-01-01

Full Text Available Transformation of organic residues into plant-available nutrients occurs through decomposition and mineralization and is mediated by saprophytic microorganisms and fauna. Of particular interest is the recycling of the essential plant elements—N, P, and S—contained in organic residues. If organic residues can supply sufficient nutrients during crop growth, a reduction in fertilizer use is possible. The challenge is synchronizing nutrient release from organic residues with crop nutrient demands throughout the growing season. This paper presents a conceptual model describing the pattern of nutrient release from organic residues in relation to crop nutrient uptake. Next, it explores experimental approaches to measure the physical, chemical, and biological barriers to decomposition and nutrient mineralization. Methods are proposed to determine the rates of decomposition and nutrient release from organic residues. Practically, this information can be used by agricultural producers to determine if plant-available nutrient supply is sufficient to meet crop demands at key growth stages or whether additional fertilizer is needed. Finally, agronomic practices that control the rate of soil biota-mediated decomposition and mineralization, as well as those that facilitate uptake of plant-available nutrients, are identified. Increasing reliance on soil biological activity could benefit crop nutrition and health in sustainable agroecosystems.

Bacterial Shifts in Nutrient Solutions Flowing Through Biofilters Used in Tomato Soilless Culture.

Science.gov (United States)

Renault, David; Déniel, Franck; Vallance, Jessica; Bruez, Emilie; Godon, Jean-Jacques; Rey, Patrice

2017-11-25

In soilless culture, slow filtration is used to eliminate plant pathogenic microorganisms from nutrient solutions. The present study focused on the characterization and the potential functions of microbial communities colonizing the nutrient solutions recycled on slow filters during a whole cultivation season of 7 months in a tomato growing system. Bacterial microflora colonizing the solutions before and after they flew through the columns were studied. Two filters were amended with Pseudomonas putida (P-filter) or Bacillus cereus strains (B-filter), and a third filter was a control (C-filter). Biological activation of filter unit through bacterial amendment enhanced very significantly filter efficacy against plant potential pathogens Pythium spp. and Fusarium oxysporum. However, numerous bacteria (10 3 -10 4  CFU/mL) were detected in the effluent solutions. The community-level physiological profiling indicated a temporal shift of bacterial microflora, and the metabolism of nutrient solutions originally oriented towards carbohydrates progressively shifted towards degradation of amino acids and carboxylic acids over the 7-month period of experiment. Single-strand conformation polymorphism fingerprinting profiles showed that a shift between bacterial communities colonizing influent and effluent solutions of slow filters occurred. In comparison with influent, 16S rDNA sequencing revealed that phylotype diversity was low in the effluent of P- and C-filters, but no reduction was observed in the effluent of the B-filter. Suppressive potential of solutions filtered on a natural filter (C-filter), where the proportion of Proteobacteria (α- and β-) increased, whereas the proportion of uncultured candidate phyla rose in P- and B-filters, is discussed.

Wood fly ash used for nutrient compensation or as a construction material. Environmental impacts related to different management alternatives; Skogsbraensleaska som naeringsresurs eller konstruktionsmaterial. Miljoeeffekter av olika hanteringsalternativ

Energy Technology Data Exchange (ETDEWEB)

Olsson, Susanna; Kaerrman, Erik; Roennblom, Tobias; Erlandsson, Aasa (Ecoloop AB, Stockholm (Sweden))

2008-08-15

The Swedish Forest Agency recommends that wood ash should be recycled to forest land, if the ashes fulfil certain threshold values. But there is also an option to use the ashes as construction material in forest roads. In this project, an environmental systems analysis approach was developed in order to assess the environmental impact from different alternatives. Three alternatives were analysed for the handling of 1 tonnes wood ash (DM) generated at the municipality of Boraas in Sweden: 1) Spreading the ashes to forests, 2) Use the ashes as a construction material in roads and 3) disposal of the ashes. Both the recycling of wood ash on forests and use of the ash for road construction have benefits in terms of saving natural resources and energy compared to disposal on landfill. Forest-recycling is the most energy efficient alternative and saves most of the resources Zn, P and dolomite. The road construction as well as the landfill alternatives results in a net-removal of the heavy metals As, Cd and Pb from the forests in a 100-year perspective, assuming that the content of these substances in the recycled ash is the same as the amount removed through biomass harvesting. Critical parameters for the results were the assumption that nutrient compensation is needed if wood ashes not are used on forests and the system boundaries chosen for assessing the heavy metal leaching. If the nutrient compensation is not considered as necessary, the influence on the results of transports and maintenance increase. One possibility for further work is to use the developed method for various regions in Sweden. The local conditions vary between different regions in terms of ash production, need for nutrient compensation and potential to build gravel roads etc

A UK perspective on recycling

International Nuclear Information System (INIS)

Williams, T.

1991-01-01

The United Kingdom, through the recycling of depleted uranium from Magnox reactors into Advanced Gas-cooled Reactor (AGR) fuel, has already recycled significant quantities of reprocessed material in reactors owned by Nuclear Electric plc and Scottish Nuclear Limited. This AGR fuel has been satisfactorily irradiated and discharged over a decade or more, and will be reprocessed in the new Thermal Oxide Reprocessing Plant (THORP), currently under construction in the UK. British Nuclear Fuels plc (BNFL) and the UK Atomic Energy Authority (UKAEA) have also been exploiting the potential of plutonium recycled in mixed oxide (MOX) fuel, which they have been making since 1963. All of the UK nuclear companies are committed to further recycling of Magnox depleted uranium during the 1990s, and it is anticipated that oxide recycling will also become firmly established during the next decade. British Nuclear Fuels and Urenco Ltd, as the providers of fuel cycle services, are developing an infrastructure to close the fuel cycle for oxide nuclear fuel, using both the uranium and plutonium arising from reprocessing. (author)

Performance evaluation of subgrade stabilization with recycled materials.

Science.gov (United States)

2016-02-29

Due to rising costs of good quality acceptable materials for remove/replace options and traditional : subgrade stabilization materials, MDOT is in need to identify potential recycled materials to treat : unacceptable subgrade soils. Use of recycled m...

Potential environmental benefits of improving recycling of polyolefines – LCA of Magnetic density separation (MDS) developed in the EU FP7 funded project W2Plastic

DEFF Research Database (Denmark)

Olsen, Stig Irving; Bonou, Alexandra

2012-01-01

identify eco-design criteria for the development and secondly to document the potential environmental improvement of polyolefin recycling using the MDS technology. A preliminary study focusing solely on the carbon footprint benefits of recycling plastic waste compared to virgin production of polymers...... showed that there are large benefits to recycling. However, including other uses of the waste illustrates that the benefits to a large extent depend on that the recycled plastic have such high quality that it can actually replace virgin plastic and also to some extent depends on which energy systems e.......g. energy recovery from incineration substitutes....

Potential for nutrient recovery and biogas production from blackwater, food waste and greywater in urban source control systems.

Science.gov (United States)

Kjerstadius, H; Haghighatafshar, S; Davidsson, Å

2015-01-01

In the last decades, the focus on waste and wastewater treatment systems has shifted towards increased recovery of energy and nutrients. Separation of urban food waste (FW) and domestic wastewaters using source control systems could aid this increase; however, their effect on overall sustainability is unknown. To obtain indicators for sustainability assessments, five urban systems for collection, transport, treatment and nutrient recovery from blackwater, greywater and FW were investigated using data from implementations in Sweden or northern Europe. The systems were evaluated against their potential for biogas production and nutrient recovery by the use of mass balances for organic material, nutrients and metals over the system components. The resulting indicators are presented in units suitable for use in future sustainability studies or life-cycle assessment of urban waste and wastewater systems. The indicators show that source control systems have the potential to increase biogas production by more than 70% compared with a conventional system and give a high recovery of phosphorus and nitrogen as biofertilizer. The total potential increase in gross energy equivalence for source control systems was 20-100%; the greatest increase shown is for vacuum-based systems.

Substitution potentials of recycled HDPE and wood particles from post-consumer packaging waste in Wood-Plastic Composites.

Science.gov (United States)

Sommerhuber, Philipp F; Welling, Johannes; Krause, Andreas

2015-12-01

The market share of Wood-Plastic Composites (WPC) is small but expected to grow sharply in Europe. This raises some concerns about suitable wood particles needed in the wood-based panels industry in Europe. Concerns are stimulated by the competition between the promotion of wooden products through the European Bioeconomy Strategy and wood as an energy carrier through the Renewable Energy Directive. Cascade use of resources and valorisation of waste are potential strategies to overcome resource scarcity. Under experimental design conditions, WPC made from post-consumer recycled wood and plastic (HDPE) were compared to WPC made from virgin resources. Wood content in the polymer matrix was raised in two steps from 0% to 30% and 60%. Mechanical and physical properties and colour differences were characterized. The feasibility of using cascaded resources for WPC is discussed. Results indicate the technical and economic feasibility of using recycled HDPE from packaging waste for WPC. Based on technical properties, 30% recycled wood content for WPC is feasible, but economic and political barriers of efficient cascading of biomass need to be overcome. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pre-study - Straw ash in a nutrient loop; Foerstudie - Halmaska i ett kretslopp

Energy Technology Data Exchange (ETDEWEB)

Ottosson, Peter; Bjurstroem, Henrik; Johansson, Christina; Svensson, Sven-Erik; Mattsson, Jan Erik

2009-03-15

A sustainable production of energy crops requires that the loss of mineral nutrients when removing biomass is compensated naturally or by an addition of plant nutrients. Recycling ash is a natural way to satisfy this need arising after combustion of energy crops. In this pre-study, the prerequisites for recycling straw ash have been investigated. The Danish experience with spreading ash to fields and information in literature on the composition of ash have been collected and presented. Analysis of straw samples taken from four different places in Scania yielded information on cadmium and nutrient concentration in straw and in ash. A balance between removal of nutrient and cadmium with wheat straw and restoring them by recycling straw ash has been computed. Straw ash is a potassium fertiliser with some phosphorus and some liming effect. It is technically difficult to spread the small quantities of ash in solid form, ca 250 kg per hectare and year in average, which a pure recycling would require. It is easier to spread larger quantities, e.g. ca 1 ton per hectare every fourth year, which corresponds to spreading once in a four year crop rotation, but then one provides too much potassium if one considers the actual needs of the coming crops at that occasion, which could lead to potassium being leached out on light soils. Alternatively, one could spread only bottom ash, but this would lead to half of the potassium content not being recycled to agricultural soil and lost with the fly ash that is disposed of. If one spreads about 500 kg bottom ash per hectare every other year, which could be a suitable strategy to avoid overloading soils with potassium, the dose brought to 1 ha may be computed as: 4 - 10 kg phosphorus, 50 - 100 kg potassium, 5 - 15 kg sulphur, 4 - 8 kg magnesium, 0.1 - 0.3 kg manganese and 20 - 40 kg CaO. These basis of these calculations is the results from the analyses performed in this study. The cadmium concentration was significantly higher in wheat

Actinide recycle potential in the integral fast reactor (IFR) fuel cycle

International Nuclear Information System (INIS)

Chang, Y.I.; Till, C.E.

1991-01-01

In the Integral Fast Reactor (IFR) development program, the entire reactor system -- reactor, fuel cycle, and waste process is being developed and optimized at the same time as a single integral entity. The use of metallic fuel in the IFR allows a radically improved fuel cycle technology. Based on the recent IFR process development, a preliminary assessment has been made to investigate the feasibility of further adapting pyrochemical processes to directly extract actinides from LWR spent fuel. The results of this assessment indicate very promising potential and two most promising flowsheet options have been identified for further research and development. This paper also summarizes current thinking on the rationale for actinide recycle, its ramifications on the geologic repository and the current high-level waste management plans, and the necessary development programs

Nutrient supply to organic agriculture as governed by EU regulations and standards in six European countries

DEFF Research Database (Denmark)

Løes, Anne Kristin; Bünemann, E.K.; Cooper, J.

2017-01-01

-farm P sources include conventional animal manure, composted or anaerobically digested organic residues, rock phosphate, and some animal residues such as meat and bone meal. The recent proposed revision of EU regulations for organic production (2014) puts less emphasis on closing nutrient cycles...... as means are taken to ensure the quality and safety of these inputs. Awareness of the need to close nutrient cycles may contribute to adapting regulations and private standards to support recycling of nutrients from society to organic agriculture. A better definition of the term “natural substance...

Potential of diatom consortium developed by nutrient enrichment for biodiesel production and simultaneous nutrient removal from waste water.

Science.gov (United States)

Marella, Thomas Kiran; Parine, Narasimha Reddy; Tiwari, Archana

2018-05-01

Because of the decreasing fossil fuel supply and increasing greenhouse gas (GHG) emissions, microalgae have been identified as a viable and sustainable feedstock for biofuel production. The major effect of the release of wastewater rich in organic compounds has led to the eutrophication of freshwater ecosystems. A combined approach of freshwater diatom cultivation with urban sewage water treatment is a promising solution for nutrient removal and biofuel production. In this study, urban wastewater from eutrophic Hussain Sagar Lake was used to cultivate a diatom algae consortium, and the effects of silica and trace metal enrichment on growth, nutrient removal, and lipid production were evaluated. The nano-silica-based micronutrient mixture Nualgi containing Si, Fe, and metal ions was used to optimize diatom growth. Respectively, N and P reductions of 95.1% and 88.9%, COD and BOD reductions of 91% and 51% with a biomass yield of 122.5 mg L -1  day -1 and lipid productivity of 37 mg L -1  day -1 were observed for cultures grown in waste water using Nualgi. Fatty acid profiles revealed 13 different fatty acids with slight differences in their percentage of dry cell weight (DCW) depending on enrichment level. These results demonstrate the potential of diatom algae grown in wastewater to produce feedstock for renewable biodiesel production. Enhanced carbon and excess nutrient utilization makes diatoms ideal candidates for co-processes such as CO 2 sequestration, biodiesel production, and wastewater phycoremediation.

Environmental suitability of recycled concrete aggregate in highways.

Science.gov (United States)

2015-01-01

The use of recycled concrete aggregate materials in highway constructions as compared to the use of virgin : materials reduces virgin natural resource demands on the environment. In order to evaluate their potential use of : recycle materials in high...

Plant Biomass Leaching for Nutrient Recovery in Closed Loop Systems Project

Science.gov (United States)

Zeitlin, Nancy P.; Wheeler, Raymond (Compiler); Lunn, Griffin

2015-01-01

Plants will be important for food and O2 production during long term human habitation in space. Recycling of nutrients (e.g., from waste materials) could reduce the resupply costs of fertilizers for growing these plants. Work at NASA's Kennedy Space Center has shown that ion exchange resins can extract fertilizer (plant essential nutrients) from human waste water, after which the residual brine could be treated with electrodialysis to recover more water and produce high value chemicals (e.g., acids and bases). In habitats with significant plant production, inedible biomass becomes a major source of solid waste. To "close the loop" we also need to recover useful nutrients and fertilizer from inedible biomass. We are investigating different approaches to retrieve nutrients from inedible plant biomass, including physical leaching with water, processing the biomass in bioreactors, changing the pH of leaching processing, and/or conducting multiple leaches of biomass residues.

Carbon dioxide recycling: emerging large-scale technologies with industrial potential.

Science.gov (United States)

Quadrelli, Elsje Alessandra; Centi, Gabriele; Duplan, Jean-Luc; Perathoner, Siglinda

2011-09-19

This Review introduces this special issue of ChemSusChem dedicated to CO(2) recycling. Its aim is to offer an up-to-date overview of CO(2) chemical utilization (inorganic mineralization, organic carboxylation, reduction reactions, and biochemical conversion), as a continuation and extension of earlier books and reviews on this topic, but with a specific focus on large-volume routes and projects/pilot plants that are currently emerging at (pre-)industrial level. The Review also highlights how some of these routes will offer a valuable opportunity to introduce renewable energy into the existing energy and chemical infrastructure (i.e., "drop-in" renewable energy) by synthesis of chemicals from CO(2) that are easy to transport and store. CO(2) conversion therefore has the potential to become a key pillar of the sustainable and resource-efficient production of chemicals and energy from renewables. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Spatial assessment of potential ecological risk of heavy metals in soils from informal e-waste recycling in Ghana

Directory of Open Access Journals (Sweden)

Vincent Nartey Kyere

2017-10-01

Full Text Available The rapidly increasing annual global volume of e-waste, and of its inherently valuable fraction, has created an opportunity for individuals in Agbogbloshie, Accra, Ghana to make a living by using unconventional, uncontrolled, primitive and crude procedures to recycle and recover valuable metals from this waste. The current form of recycling procedures releases hazardous fractions, such as heavy metals, into the soil, posing a significant risk to the environment and human health. Using a handheld global positioning system, 132 soil samples based on 100 m grid intervals were collected and analysed for cadmium (Cd, chromium (Cr, copper (Cu, mercury (Hg, lead (Pb and zinc (Zn. Using geostatistical techniques and sediment quality guidelines, this research seeks to assess the potential risk these heavy metals posed to the proposed Korle Ecological Restoration Zone by informal e-waste processing site in Agbogbloshie, Accra, Ghana. Analysis of heavy metals revealed concentrations exceeded the regulatory limits of both Dutch and Canadian soil quality and guidance values, and that the ecological risk posed by the heavy metals extended beyond the main burning and dismantling sites of the informal recyclers to the school, residential, recreational, clinic, farm and worship areas. The heavy metals Cr, Cu, Pb and Zn had normal distribution, spatial variability, and spatial autocorrelation. Further analysis revealed the decreasing order of toxicity, Hg>Cd>Pb> Cu>Zn>Cr, of contributing significantly to the potential ecological risk in the study area.

The potential contribution of yellow cassava to dietary nutrient adequacy of primary-school children in Eastern Kenya; the use of linear programming.

Science.gov (United States)

Talsma, Elise F; Borgonjen-van den Berg, Karin J; Melse-Boonstra, Alida; Mayer, Eva V; Verhoef, Hans; Demir, Ayşe Y; Ferguson, Elaine L; Kok, Frans J; Brouwer, Inge D

2018-02-01

Introduction of biofortified cassava as school lunch can increase vitamin A intake, but may increase risk of other deficiencies due to poor nutrient profile of cassava. We assessed the potential effect of introducing a yellow cassava-based school lunch combined with additional food-based recommendations (FBR) on vitamin A and overall nutrient adequacy using Optifood (linear programming tool). Cross-sectional study to assess dietary intakes (24 h recall) and derive model parameters (list of foods consumed, median serving sizes, food and food (sub)group frequency distributions, food cost). Three scenarios were modelled, namely daily diet including: (i) no school lunch; (ii) standard 5d school lunch with maize/beans; and (iii) 5d school lunch with yellow cassava. Each scenario and scenario 3 with additional FBR were assessed on overall nutrient adequacy using recommended nutrient intakes (RNI). Eastern Kenya. Primary-school children (n 150) aged 7-9 years. Best food pattern of yellow cassava-based lunch scenario achieved 100 % RNI for six nutrients compared with no lunch (three nutrients) or standard lunch (five nutrients) scenario. FBR with yellow cassava and including small dried fish improved nutrient adequacy, but could not ensure adequate intake of fat (52 % of average requirement), riboflavin (50 % RNI), folate (59 % RNI) and vitamin A (49 % RNI). Introduction of yellow cassava-based school lunch complemented with FBR potentially improved vitamin A adequacy, but alternative interventions are needed to ensure dietary adequacy. Optifood is useful to assess potential contribution of a biofortified crop to nutrient adequacy and to develop additional FBR to address remaining nutrient gaps.

An assessment of the potential radiation exposure from residual radioactivity in scrap metal for recycling

International Nuclear Information System (INIS)

Lee, Sang Yoon; Lee, Kun Jai

1997-01-01

With current waste monitoring technology it is reasonable to assume that much of the material designated as low level waste (LLW), generated within nuclear facilities, is in fact uncontaminated. This may include operational wastes, metal and rubble, office waste and discrete items from decommissioning or decontamination operations. Materials that contain only trivial quantities of radionuclides could realistically be exempted or released from regulatory control for recycle or reuse. A criterion for uncontrolled disposal of low-level radioactive contaminated waste is that the radiation exposure of the public and of each individual caused by this disposal is so low that radiation protection measures need not be taken. The International Atomic Energy Agency (IAEA) suggests an annual effective doses of 10 μ Sv as a limit for the individual radiation dose. In 1990, new recommendation on radiation protection standards was developed by International Commission on Radiological Protection (ICRP) to take into account new biological information related to the detriment associated with radiation exposure. Adoption of these recommendations necessitated a revision of the Commission's secondary limits contained in Publication 30, Parts 1 ∼ 4. This study summarized the potential radiation exposure from valuable scrap metal considered to uncontrolled recycle by new ICRP recommendations. Potential exposure pathways to people following were analyzed and relevant models developed. Finally, concentrations leading to an individual dose of 10 μ Sv/yr were calculated for 14 key radionuclides. These potential radiation exposures are compared with the results of an IAEA study. 12 refs., 6 tabs., figs

Potential application of palladium nanoparticles as selective recyclable hydrogenation catalysts

International Nuclear Information System (INIS)

Mukherjee, DebKumar

2008-01-01

The search for more efficient catalytic systems that might combine the advantages of both homogeneous (catalyst modulation) and heterogeneous (catalyst recycling) catalysis is one of the most exciting challenges of modern chemistry. More recently with the advances of nanochemistry, it has been possible to prepare soluble analogues of heterogeneous catalysts. These nanoparticles are generally stabilized against aggregation into larger particles by electrostatic or steric protection. Herein we demonstrate the use of room temperature ionic liquid for the stabilization of palladium nanoparticles that are recyclable catalysts for the hydrogenation of carbon-carbon double bonds and application of these catalysts to the selective hydrogenation of internal or terminal C=C bonds in unsaturated primary alcohols. The particles suspended in room temperature ionic liquid show no metal aggregation or loss of catalytic activity even on prolonged use

Recycling Improves Soil Fertility Management in Smallholdings in Tanzania

Directory of Open Access Journals (Sweden)

Ariane Krause

2018-02-01

Full Text Available Residues from bioenergy and ecological sanitation (EcoSan can be utilized to sustain soil fertility and productivity. With regard to certain cooking and sanitation technologies used in smallholder households (hh, we systematically analyzed how utilization of the respective potentials to recover residues for farming affects (i soil nutrient balances, (ii the potential for subsistence production of composts, and (iii environmental emissions. On the example of an intercropping farming system in Karagwe, Tanzania, we studied specific farming practices including (1 current practices of using standard compost only; (2 a combination of using biogas slurry, urine, and standard compost; (3 a combination of using so-called “CaSa-compost” (containing biochar and sanitized human excreta, Project “Carbonization and Sanitation”, urine, and standard compost. The system analysis combines a soil nutrient balance (SNB with material flow analysis (MFA. Currently, nitrogen (N and phosphorus (P are depleted by −54 ± 3 and −8 ± 1 kg∙ha−1∙year−1, respectively. Our analysis shows, however, a clear potential to reduce depletion rates of N, and to reverse the SNB of P, to bring about a positive outcome. Composts and biogas slurry supply sufficient P to crops, while urine effectively supplements N. By using resources recovered from cooking and sanitation, sufficient compost for subsistence farming may be produced. Human excreta contribute especially to total N and total P in CaSa-compost, whilst biochar recovered from cooking with microgasifier stoves adds to total carbon (C and total P. We conclude that the combined recycling of household residues from cooking and from sanitation, and CaSa-compost in particular, is especially suitable for sustainable soil management, as it mitigates existing P-deficiency and soil acidity, and also restores soil organic matter.

Recycling of polymers: a review.

Science.gov (United States)

Ignatyev, Igor A; Thielemans, Wim; Vander Beke, Bob

2014-06-01

Plastics are inexpensive, easy to mold, and lightweight. These and many other advantages make them very promising candidates for commercial applications. In many areas, they have substantially suppressed traditional materials. However, the problem of recycling still is a major challenge. There are both technological and economic issues that restrain the progress in this field. Herein, a state-of-art overview of recycling is provided together with an outlook for the future by using popular polymers such as polyolefins, poly(vinyl chloride), polyurethane, and poly(ethylene terephthalate) as examples. Different types of recycling, primary, secondary, tertiary, quaternary, and biological recycling, are discussed together with related issues, such as compatibilization and cross-linking. There are various projects in the European Union on research and application of these recycling approaches; selected examples are provided in this article. Their progress is mirrored by granted patents, most of which have a very limited scope and narrowly cover certain technologies. Global introduction of waste utilization techniques to the polymer market is currently not fully developed, but has an enormous potential. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biochar-enhanced composts reduce the potential leaching of nutrients and heavy metals and suppress plant-parasitic nematodes in excessively fertilized cucumber soils.

Science.gov (United States)

Cao, Yune; Gao, Yanming; Qi, Yanbin; Li, Jianshe

2018-03-01

Excessive fertilization is a common agricultural practice that has largely reduced soil nutrient retention capacity and led to nutrient leaching in China. To reduce nutrient leaching, in this study, we evaluated the application of biochar, compost, and biochar-compost on soil properties, leaching water quality, and cucumber plant growth in soils with different nutrient levels. In general, the concentrations of nutrients and heavy metals in leaching water were higher under high-nutrient conditions than under low-nutrient conditions. Both biochar and compost efficiently enhanced soil cation exchange capacity (CEC), water holding capacity (WHC), and microbial biomass carbon (MBC), nitrogen (MBN), and phosphorus (MBP), reduced the potential leaching of nutrients and heavy metals, and improved plant growth. The efficiency of biochar and compost in soil CEC, WHC, MBC, MBN, and MBP and plant growth was enhanced when applied jointly. In addition, biochar and biochar-enhanced compost efficiently suppressed plant-parasitic nematode infestation in a soil with high levels of both N and P. Our results suggest that biochar-enhanced compost can reduce the potential environmental risks in excessively fertilized vegetable soils.

Nutrient recycle from defatted microalgae (Aurantiochytrium) with hydrothermal treatment for microalgae cultivation.

Science.gov (United States)

Aida, Taku Michael; Maruta, Ryouma; Tanabe, Yuuhiko; Oshima, Minori; Nonaka, Toshiyuki; Kujiraoka, Hiroki; Kumagai, Yasuaki; Ota, Masaki; Suzuki, Iwane; Watanabe, Makoto M; Inomata, Hiroshi; Smith, Richard L

2017-03-01

Defatted heterotrophic microalgae (Aurantiochytrium limacinum SR21) was treated with high temperature water (175-350°C, 10-90min) to obtain nitrogen and phosphorous nutrients as a water soluble fraction (WS). Yields of nitrogen and phosphorous recovered in WS varied from 38 to 100% and from 57 to 99%, respectively. Maximum yields of nitrogen containing compounds in WS were proteins (43%), amino acids (12%) and ammonia (60%) at treatment temperatures of 175, 250 and 350°C, respectively. Maximum yield of phosphorous in WS was 99% at a treatment temperature of 250°C. Cultivation experiments of microalgae (A. limacinum SR21) using WS obtained at 200 and 250°C showed positive growth. Water soluble fractions from hydrothermal treatment of defatted microalgae are effective nitrogen and phosphorous nutrient sources for microalgae cultivation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Urban Mines of Copper: Size and Potential for Recycling in the EU

Directory of Open Access Journals (Sweden)

Luca Ciacci

2017-01-01

Full Text Available Copper is among the most important metals by production volume and variety of applications, providing essential materials and goods for human wellbeing. Compared to other world regions, Europe has modest natural reserves of copper and is highly dependent on imports to meet the domestic demand. Securing access to raw materials is of strategic relevance for Europe and the recycling of urban mines (also named “in-use stock” is a significant mean to provide forms of secondary copper to the European industry. A dynamic material flow analysis model is applied to characterize the flows of copper in the European Union (EU-28 from 1960 to 2014 and to determine the accumulation of this metal in the in-use stock. A scrap balance approach is applied to reconcile the flow of secondary copper sent to domestic recycling estimated through the model and that reported by historic statistics. The results show that per capita in-use stock amounts at 160–200 kg/person, and that current end-of-life recycling rate is around 60%. The quantification of historic flows provides a measure of how the European copper cycle has changed over time and how it may evolve in the future: major hindrances to recycling are highlighted and perspectives for improving the current practices at end-of-life are discussed.

Management options for recycling radioactive scrap metals

Energy Technology Data Exchange (ETDEWEB)

Dehmel, J.C.; MacKinney, J.; Bartlett, J.

1997-02-01

The feasibility and advantages of recycling radioactive scrap metals (RSM) have yet to be assessed, given the unique technical, regulatory, safety, and cost-benefit issues that have already been raised by a concerned recycling industry. As is known, this industry has been repeatedly involved with the accidental recycling of radioactive sources and, in some cases, with costly consequences. If recycling were deemed to be a viable option, it might have to be implemented with regulatory monitoring and controls. Its implementation may have to consider various and complex issues and address the requirements and concerns of distinctly different industries. There are three basic options for the recycling of such scraps. They are: (1) recycling through the existing network of metal-scrap dealers and brokers, (2) recycling directly and only with specific steelmills, or (3) recycling through regional processing centers. Under the first option, scrap dealers and brokers would receive material from RSM generators and determine at which steelmills such scraps would be recycled. For the second option, RSM generators would deal directly with selected steelmills under specific agreements. For the third option, generators would ship scraps only to regional centers for processing and shipment to participating steelmills. This paper addresses the potential advantages of each option, identifies the types of arrangements that would need to be secured among all parties, and attempts to assess the receptivity of the recycling industry to each option.

Proline Precursors and Collagen Synthesis: Biochemical Challenges of Nutrient Supplementation and Wound Healing.

Science.gov (United States)

Albaugh, Vance L; Mukherjee, Kaushik; Barbul, Adrian

2017-11-01

Wound healing is a complex process marked by highly coordinated immune fluxes into an area of tissue injury; these are required for re-establishment of normal tissue integrity. Along with this cascade of cellular players, wound healing also requires coordinated flux through a number of biochemical pathways, leading to synthesis of collagen and recycling or removal of damaged tissues. The availability of nutrients, especially amino acids, is critical for wound healing, and enteral supplementation has been intensely studied as a potential mechanism to augment wound healing-either by increasing tensile strength, decreasing healing time, or both. From a practical standpoint, although enteral nutrient supplementation may seem like a reasonable strategy to augment healing, a number of biochemical and physiologic barriers exist that limit this strategy. In this critical review, the physiology of enteral amino acid metabolism and supplementation and challenges therein are discussed in the context of splanchnic physiology and biochemistry. Additionally, a review of studies examining various methods of amino acid supplementation and the associated effects on wound outcomes are discussed. © 2017 American Society for Nutrition.

Multimodal network design for sustainable household plastic recycling

NARCIS (Netherlands)

Bing Xiaoyun, Xiaoyun; Groot, J.J.; Bloemhof, J.M.; Vorst, van der J.G.A.J.

2013-01-01

Purpose – This research studies a plastic recycling system from a reverse logistics angle and investigates the potential benefits of a multimodality strategy to the network design of plastic recycling. This research aims to quantify the impact of multimodality on the network, to provide decision

Recycling Facilities - Land Recycling Cleanup Locations

Data.gov (United States)

NSGIC Education | GIS Inventory — Land Recycling Cleanup Location Land Recycling Cleanup Locations (LRCL) are divided into one or more sub-facilities categorized as media: Air, Contained Release or...

Actinide recycle potential in the Integral Fast Reactor (IFR) fuel cycle

International Nuclear Information System (INIS)

Chang, Y.I.; Till, C.E.

1990-01-01

In the Integral Fast Reactor (IFR) development program, the entire reactor system -- reactor, fuel cycle, and waste process is being developed and optimized at the same time as a single integral entity. The use of metallic fuel in the IFR allows a radically improved fuel cycle technology. Pyroprocessing, which utilizes high temperatures and molten salt and molten metal solvents, can be advantageously utilized for processing metal fuels because the product is metal suitable for fabrication into new fuel elements. The key step in the IFR process is electrorefining, which provides for recovery of the valuable fuel constituents, uranium and plutonium, and for removal of fission products. In the electrorefining operation, uranium and plutonium are selectively transported from an anode to a cathode, leaving impurity elements, mainly fission products, either in the anode compartment or in a molten salt electrolyte. A notable feature of the IFR process is that the actinide elements accompany plutonium through the process. This results in a major advantage in the high-level waste management, because these actinides are automatically recycled back into the reactor for in-situ burning. Based on the recent IFR process development, a preliminary assessment has also been made to investigate the feasibility of further adapting the pyrochemical processes to directly extract actinides from LWR spent fuel. The results of this assessment indicate very promising potential and two most promising flowsheet options have been identified for further research and development. This paper also summarizes current thinking on the rationale for actinide recycle, its ramifications on the geologic repository and the current high-level waste management plans, and the necessary development programs. 5 refs., 4 figs., 4 tabs

Predicted harvest time effects on switchgrass moisture content, nutrient concentration, yield, and profitability

Science.gov (United States)

Production costs change with harvest date of switchgrass (Panicum virgatum L.) as a result of nutrient recycling and changes in yield of this perennial crop. This study examines the range of cost of production from an early, yield-maximizing harvest date to a late winter harvest date at low moisture...

Mechanical and chemical recycling of solid plastic waste.

Science.gov (United States)

Ragaert, Kim; Delva, Laurens; Van Geem, Kevin

2017-11-01

This review presents a comprehensive description of the current pathways for recycling of polymers, via both mechanical and chemical recycling. The principles of these recycling pathways are framed against current-day industrial reality, by discussing predominant industrial technologies, design strategies and recycling examples of specific waste streams. Starting with an overview on types of solid plastic waste (SPW) and their origins, the manuscript continues with a discussion on the different valorisation options for SPW. The section on mechanical recycling contains an overview of current sorting technologies, specific challenges for mechanical recycling such as thermo-mechanical or lifetime degradation and the immiscibility of polymer blends. It also includes some industrial examples such as polyethylene terephthalate (PET) recycling, and SPW from post-consumer packaging, end-of-life vehicles or electr(on)ic devices. A separate section is dedicated to the relationship between design and recycling, emphasizing the role of concepts such as Design from Recycling. The section on chemical recycling collects a state-of-the-art on techniques such as chemolysis, pyrolysis, fluid catalytic cracking, hydrogen techniques and gasification. Additionally, this review discusses the main challenges (and some potential remedies) to these recycling strategies and ground them in the relevant polymer science, thus providing an academic angle as well as an applied one. Copyright © 2017 Elsevier Ltd. All rights reserved.

Economic potential of fuel recycling options: A lifecycle cost analysis of future nuclear system transition in China

International Nuclear Information System (INIS)

Gao, Ruxing; Choi, Sungyeol; Il Ko, Won; Kim, Sungki

2017-01-01

In today's profit-driven market, how best to pursue advanced nuclear fuel cycle technologies while maintaining the cost competitiveness of nuclear electricity is of crucial importance to determine the implementation of spent fuel reprocessing and recycling in China. In this study, a comprehensive techno-economic analysis is undertaken to evaluate the economic feasibility of ongoing national projects and the technical compatibility with China's future fuel cycle transition. We investigated the dynamic impacts of technical and economic uncertainties in the lifecycle of a nuclear system. The electricity generation costs associated with four potential fuel cycle transition scenarios were simulated by probabilistic and deterministic approaches and then compared in detail. The results showed that the total cost of a once-through system is lowest compared those of other advanced systems involving reprocessing and recycling. However, thanks to the consequential uncertainties caused by the further progress toward technology maturity, the economic potential of fuel recycling options was proven through a probabilistic uncertainty analysis. Furthermore, it is recommended that a compulsory executive of closed fuel cycle policy would pose some investment risk in the near term, though the execution of a series of R&D initiatives with a flexible roadmap would be valuable in the long run. - Highlights: • Real-time economic performance of the four scenarios of China's nuclear fuel cycle system transition until 2100. • Systematic assessments of techno-economic feasibility for ongoing national reprocessing projects. • Investigation the cost impact on nuclear electricity generation caused by uncertainties through probabilistic analysis. • Recommendation for sustainable implementation of fuel cycle R&D initiative ingrate with flexible roadmap in the long run.

Recycling of osmotic solutions in microwave-osmotic dehydration: product quality and potential for creation of a novel product.

Science.gov (United States)

Wray, Derek; Ramaswamy, Hosahalli S

2016-08-01

Despite osmotic dehydration being a cost effective process for moisture removal, the cost implications of making, regenerating, and properly disposing of the spent osmotic solutions contributes greatly to the economic feasibility of the drying operation. The potential for recycling of osmotic solutions and their use for creation of a novel product was explored using microwave-osmotic dehydration under continuous flow spray (MWODS) conditions. Identical runs were repeated 10 times to determine the progressive physical and compositional effects of the thermal treatment and leaching from the cranberry samples. The microbiological stability and constant drying performance indicated that MWODS would be well suited for employing recycled solutions. While the anthocyanin content of the solution never approached that of cranberry juice concentrate, it is demonstrated that the spent syrup can infuse these health positive components into another product (apple). This study found that re-using osmotic solutions is a viable option to reduce cost in future MWODS applications, with no detriment to product quality and potential to use the spent solution for novel products. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Nutrient balances in the forest energy cycle

International Nuclear Information System (INIS)

Olsson, Bengt

2006-02-01

In Sweden, recycling of stabilised wood-ashes to forests is considered to compensate for nutrient removals from whole-tree harvesting (i.e. use of harvest residues - slash - for energy purposes). This study has analysed nutrient fluxes through the complete forest energy cycle and estimated mass balances of nutrients in harvested biomass with those in ashes, to investigate the realism in large-scale nutrient compensation with wood-ash. Expected nutrient fluxes from forests through energy plants were calculated based on nutrient and biomass data of forest stands in the Nordic countries, and from data on nutrient fluxes through CFB-plants. The expected stoichiometric composition of wood-ashes was compared with the composition of CFB-fly ashes from various Swedish energy plants. Nutrient contents for different tree fractions were calculated to express the average nutrient concentrations in slash and stems with bark, respectively. A nutrient budget synthesis of the effects of whole-tree harvesting on base cation turnover in the following stand was presented for two experimental sites. Major conclusions from the study are: In the CFB-scenario, where the bottom ash is deposited and only the fly ash can be applied to forests, the fly ash from the slash do not meet the demands for nutrient compensation for slash harvesting. Stem material (50% wood, 50% bark) must be added at equivalent amounts, as the slash to produce the amounts of fly ash needed for compensation of slash harvesting. In the scenario where more stem material was added (75% of total fuel load), the amounts of fly ashes produced hardly compensated for nutrient removals with both stem and slash harvesting. The level of nutrient compensation was lowest for potassium. The stoichiometric nutrient composition of CFB-fly ashes from Swedish energy plants is not similar with the nutrient composition of tree biomass. The higher Ca/P ratio in ashes is only partly explained by the mixture of fuels (e.g. increasing bark

Nuclear recycling

International Nuclear Information System (INIS)

Spinrad, B.I.

1985-01-01

This paper discusses two aspects of the economics of recycling nuclear fuel: the actual costs and savings of the recycling operation in terms of money spent, made, and saved; and the impact of the recycling on the future cost of uranium. The authors review the relevant physical and chemical processes involved in the recycling process. Recovery of uranium and plutonium is discussed. Fuel recycling in LWRs is examined and a table presents the costs of reprocessing and not reprocessing. The subject of plutonium in fast reactors is addressed. Safeguards and weapons proliferation are discussed

Software recycling at the Hanford Site

International Nuclear Information System (INIS)

HINKELMAN, K.C.

1999-01-01

The Hanford Site was the first Department of Energy (DOE) complex to recycle excess software rather than dispose of it in the landfill. This plan, which took over a year to complete, was reviewed for potential legal conflicts, which could arise from recycling rather than disposal of software. It was determined that recycling was an approved method of destruction and therefore did not conflict with any of the licensing agreements that Hanford had with the software manufacturers. The Hanford Recycling Program Coordinator combined efforts with Pacific Northwest National Laboratory (PNNL) to recycle all Hanford software through a single contract, which went out for bid in January 1995. It was awarded to GreenDisk, Inc. located in Woodinville Washington and implemented in March 1995. The contract was later re-bid and awarded to EcoDisWGreenDisk in December 1998. The new contract included materials such as; software manuals, diskettes, tyvek wrapping, cardboard and paperboard packaging, compact disks (CDs), videotapes, reel-to-reel tapes, magnetic tapes, audio tapes, and many other types of media

Survey of attitudes and perceptions of urine-diverting toilets and human waste recycling in Hawaii

International Nuclear Information System (INIS)

Lamichhane, Krishna M.; Babcock, Roger W.

2013-01-01

Urine constitutes only about 1% of domestic sewage but contains 50% or more of the excreted nutrients and chemicals like hormones and pharmaceutical residues. Urine diverting toilet (UDT) systems can be considered a more sustainable alternative to wastewater management because they allow nutrient recycling, reduce water use, and allow source-separation of hormones and chemicals that can harm the environment. An online survey was conducted to determine whether UDTs are acceptable to the general public in Hawaii and if attitudes and perceptions towards it and human waste (HW) recycling vary with age, sex, level of education, religious affiliation, ethnicity, and employment status. The survey was also intended to detect possible drivers and barriers for the UDTs. Variations on variables were tested at 5% significance (p = 0.05) level (Chi-squared test or ANOVA) and considered significantly different if the p-value was less than 0.05. The results were encouraging as more than 60% are willing to pay extra for the UDT, while only 22% knew that such systems existed. No statistically significant difference was found between males and females on all survey questions at the 5% level. However, females had higher willingness to pay (WTP) than males and WTP increased with age and income. The WTP of Caucasians was higher than Asians and differed significantly. Some respondents expressed concern about the legal provisions for recycling of HW. The survey results indicate that with a public education program, it is possible that most people would be willing to adopt UDTs and HW recycling with incurred societal benefits of reduced water and fertilizer use, reduced greenhouse gas emissions, and collection of micropollutants at the source to prevent their entry into waterways. Because of the small sample size (N = 132, 13% response rate) the survey is not representative but may be indicative of the general attitude of Hawaiian people. - Highlights: ► Urine diverting toilets (UDTs

Survey of attitudes and perceptions of urine-diverting toilets and human waste recycling in Hawaii

Energy Technology Data Exchange (ETDEWEB)

Lamichhane, Krishna M., E-mail: lamichha@hawaii.edu [University of Hawaii, Department of Civil and Environmental Engineering, 2540 Dole Street, Holmes Hall 283, Honolulu, Hawaii 96822 (United States); Babcock, Roger W., E-mail: rbabcock@hawaii.edu [University of Hawaii, Department of Civil and Environmental Engineering, Holmes Hall 383, Honolulu, Hawaii 96822 (United States)

2013-01-15

Urine constitutes only about 1% of domestic sewage but contains 50% or more of the excreted nutrients and chemicals like hormones and pharmaceutical residues. Urine diverting toilet (UDT) systems can be considered a more sustainable alternative to wastewater management because they allow nutrient recycling, reduce water use, and allow source-separation of hormones and chemicals that can harm the environment. An online survey was conducted to determine whether UDTs are acceptable to the general public in Hawaii and if attitudes and perceptions towards it and human waste (HW) recycling vary with age, sex, level of education, religious affiliation, ethnicity, and employment status. The survey was also intended to detect possible drivers and barriers for the UDTs. Variations on variables were tested at 5% significance (p = 0.05) level (Chi-squared test or ANOVA) and considered significantly different if the p-value was less than 0.05. The results were encouraging as more than 60% are willing to pay extra for the UDT, while only 22% knew that such systems existed. No statistically significant difference was found between males and females on all survey questions at the 5% level. However, females had higher willingness to pay (WTP) than males and WTP increased with age and income. The WTP of Caucasians was higher than Asians and differed significantly. Some respondents expressed concern about the legal provisions for recycling of HW. The survey results indicate that with a public education program, it is possible that most people would be willing to adopt UDTs and HW recycling with incurred societal benefits of reduced water and fertilizer use, reduced greenhouse gas emissions, and collection of micropollutants at the source to prevent their entry into waterways. Because of the small sample size (N = 132, 13% response rate) the survey is not representative but may be indicative of the general attitude of Hawaiian people. - Highlights: ► Urine diverting toilets (UDTs

Episodic Salinization of Urban Rivers: Potential Impacts on Carbon, Cation, and Nutrient Fluxes

Science.gov (United States)

Haq, S.; Kaushal, S.

2017-12-01

Human dominated watersheds are subjected to an array of salt inputs (e.g. road salts), and in urban areas, infrastructure and impervious surfaces quickly drain applied road salts into the river channel. As a result, many streams experience episodic salinization over the course of hours to days following a snow event (e.g. road salt pulse), and long-term salinization over the course of seasons to decades. Salinization of streams can release contaminants (e.g. heavy metals), reduce biodiversity, and degrade drinking water quality. We investigated the water quality effects of episodic salinization in urban streams. Sediment and streamwater were incubated from twelve sites in the Baltimore-Washington Metropolitan Area under a range of sodium chloride treatments in a lab environment to mimic a vertical stream column with a sediment-water interface undergoing episodic salinization, and to characterize relationships between experimental salinization and nutrient/cation fluxes. Eight sites (Baltimore) exhibit a land use gradient and are routinely monitored within the Baltimore Ecosystem Study LTER project, and four sites (Washington DC) are suburban and offer a contrasting lithology and physiographic province. Our research suggests that salinization can mobilize total dissolved nitrogen, soluble reactive phosphorous, and base cations; potentially due to coupled biotic-abiotic processes, such as ion exchange, rapid nitrification, pH changes, and chloride-organic matter dispersal. The impact of salinization on dissolved inorganic and organic carbon varied between sites, potentially due to sediment composition, organic matter content, and ambient water quality. We contrasted the experimental results with measurements of salinization (specific conductance) and nutrients (nitrate) from real-time sensors operated by the US Geological Survey that encompass the same watersheds as our experimental sites. Sensor data was analyzed to provide insight on the timescales of salinity-nutrient

Knowledge Transfer from the Forestry Sector to the Agricultural Sector concerning Ash Recycling; Kunskapsoeverfoering fraan skogssektorn till jordbrukssektorn angaaende askaaterfoering

Energy Technology Data Exchange (ETDEWEB)

Olsson, Johanna; Salomon, Eva

2009-02-15

Cultivation of energy crops on arable land is increasing in Sweden. More than half these crops can be used for combustion, increasing the amount of ash that can be recycled to arable land. Ash is an interesting agricultural fertiliser, but more knowledge is needed before it can be applied and handled in a controlled way. Knowledge and experience concerning recycling of ash within the forest sector can be transferred to the agricultural sector. This project examined ways for ash producers to ensure safe long-term disposal of ash and to improve plant nutrient recycling. The overall aims were to identify experiences and knowledge within forestry that could be applied in agriculture; to identify gaps in knowledge and research requirements regarding ash recycling to arable land; and to produce recommendations on how to increase ash recycling. Literature describing the conditions for ash application to arable land and existing knowledge about ash recycling to forestry were reviewed. Nutrient balances were drawn up for phosphorus, cadmium, zinc and copper, which are relevant in biofuel ash recycling to agriculture. Data on ash application, mainly on forest land, were collected through telephone interviews. For ash to be more attractive for farmers, the ash product must be a realistic alternative to artificial fertilisers. Research and demonstration projects are needed to study the effects of ash on yield and quality in different crops. Different biofuel ash products have differing qualities and can thus have different fields of application within agriculture and can be applied in varying amounts. For example, clean straw ash has a low P and Cd content and mainly supplies potassium and lime. The balance calculations showed that the highest quality ash for arable land is bottom ash from grate combustion of forest trash with 2-5 % of willow. There are both differences and similarities between ash application in agriculture and forestry. An important feature is the

Long term effects of ash recycling on soil and water chemistry in forests

International Nuclear Information System (INIS)

Westling, Olle; Kronnaes, Veronika

2006-02-01

IVL Swedish Environmental Research Institute has studied the long-term need of compensatory fertilisation (e.g. wood ash recycling) after whole tree harvest in coniferous forests in Sweden. The study is based on dynamic model calculations with scenarios including reduced atmospheric deposition of air pollutants and different intensity of forest management. The possibilities to counteract acidification in soil and water with application of stabilised wood ash are discussed. The reduction in deposition of acidifying air pollutants in Sweden up to 2010 is expected to contribute to a significant recovery from acidification in soil- and runoff water in forests. The recovery of the forest soil (e.g. base saturation ) will, however, be slow according to the model calculations, especially if compensatory fertilisation is not carried out in managed areas. The model calculations indicate that the harvest of stemwood will have limited impact on the future acidity of soil and run off water from well drained forest soils. This conclusion is based on a comparison with a scenario where no harvest is assumed. More important for recovery from acidification is further reduction of acidifying air pollutants, even after 2010. Harvest of stemwood in combination with extraction of harvest residues has the potential to cause significant and long term acidification of soils in the future, especially in areas with high forest production and slow weathering rate. The results of the study indicate a need of compensatory fertilisation in these areas if whole tree harvest is applied, especially if the deposition of air pollutants have been high in the past. Field studies have shown that acidification effects of whole tree harvest can be counteracted by wood ash recycling to forest soils, due to the high content of calcium- and magnesium-rich minerals in the ashes. However, the dose should be adjusted to the need of increasing the acid neutralising capacity in the soil and runoff and the actual

Recycling of cellulases in a continuous process for production of bioethanol

DEFF Research Database (Denmark)

Haven, Mai Østergaard

studies, this PhD project investigates enzyme recycling at industrial relevant conditions in the Inbicon process, e.g. high dry matter conditions and process configurations that could be implemented in large scale. The results point towards potential processes for industrial recycling of enzymes......The focus of the work presented in this thesis is recycling of commercial enzymes in a continuous process for production of bioethanol from biomass. To get a deeper understanding of the factors affecting the potential for enzyme recycling, the interactions between enzymes and biomass......, the adsorption and desorption as well as stability and recovery of activity was investigated. More knowledge on these factors have enabled a process adapted for enzyme recycling. The driver being that enzyme consumption remains a major cost when producing bioethanol from lignocellulosic biomass. Unlike previous...

Metallic mercury recycling. Final report

Energy Technology Data Exchange (ETDEWEB)

Beck, M.A.

1994-07-01

Metallic mercury is known to be a hazardous material and is regulated as such. The disposal of mercury, usually by landfill, is expensive and does not remove mercury from the environment. Results from the Metallic Mercury Recycling Project have demonstrated that metallic mercury is a good candidate for reclamation and recycling. Most of the potential contamination of mercury resides in the scum floating on the surface of the mercury. Pinhole filtration was demonstrated to be an inexpensive and easy way of removing residues from mercury. The analysis method is shown to be sufficient for present release practices, and should be sufficient for future release requirements. Data from tests are presented. The consistently higher level of activity of the filter residue versus the bulk mercury is discussed. Recommendations for the recycling procedure are made.

Metallic mercury recycling. Final report

International Nuclear Information System (INIS)

Beck, M.A.

1994-01-01

Metallic mercury is known to be a hazardous material and is regulated as such. The disposal of mercury, usually by landfill, is expensive and does not remove mercury from the environment. Results from the Metallic Mercury Recycling Project have demonstrated that metallic mercury is a good candidate for reclamation and recycling. Most of the potential contamination of mercury resides in the scum floating on the surface of the mercury. Pinhole filtration was demonstrated to be an inexpensive and easy way of removing residues from mercury. The analysis method is shown to be sufficient for present release practices, and should be sufficient for future release requirements. Data from tests are presented. The consistently higher level of activity of the filter residue versus the bulk mercury is discussed. Recommendations for the recycling procedure are made

Determination of Plant-Available Nutrients in Two Wood Ashes: the Influence of Combustion Conditions

Czech Academy of Sciences Publication Activity Database

Perná, Ivana; Ochecová, P.; Száková, J.; Hanzlíček, Tomáš; Tlustoš, P.

2016-01-01

Roč. 47, 13/14 (2016), 1664-1674 ISSN 0010-3624 R&D Projects: GA MZe QI102A207 Institutional support: RVO:67985891 Keywords : combustion condition * crystal phases * fertilizer * plant-available nutrients * wood ash Subject RIV: DM - Solid Waste and Recycling Impact factor: 0.589, year: 2016

Modelling Recycling Targets

DEFF Research Database (Denmark)

Hill, Amanda Louise; Leinikka Dall, Ole; Andersen, Frits M.

2014-01-01

Within the European Union (EU) a paradigm shift is currently occurring in the waste sector, where EU waste directives and national waste strategies are placing emphasis on resource efficiency and recycling targets. The most recent Danish resource strategy calculates a national recycling rate of 22......% for household waste, and sets an ambitious goal of a 50% recycling rate by 2020. This study integrates the recycling target into the FRIDA model to project how much waste and from which streams should be diverted from incineration to recycling in order to achieve the target. Furthermore, it discusses how...... the existing technological, organizational and legislative frameworks may affect recycling activities. The results of the analysis show that with current best practice recycling rates, the 50% recycling rate cannot be reached without recycling of household biowaste. It also shows that all Danish municipalities...

Unconventional recycling

Energy Technology Data Exchange (ETDEWEB)

White, K.M.

1996-05-01

Despite advances made in recycling technology and markets for materials over the past few years, recycling at convention centers, particularly on the show floor itself, can be a vexing problem. Part of the problem lies in the fact that recycling at convention centers has more to do with logistics than it does with these industry trends. However, given the varied nature of convention centers, and the shows they book, a rigid approach to recycling at convention centers is not always feasible. Like the numerous different curbside programs serving communities across the country, what works for one convention center--and one show--many not work for another. These difficulties notwithstanding, more convention centers are offering recycling programs today, and more groups booking conventions these days have begun requesting recycling services.

Potential effects of nutrient profiles on nutrient intakes in the Netherlands, Greece, Spain, USA, Israel, China and South-Africa

NARCIS (Netherlands)

Roodenburg, Annet J C; Schlatmann, Anke; Dötsch-Klerk, Mariska; Daamen, Robert; Dong, Jie; Guarro, Marta; Stergiou, Margarita; Sayed, Nazeeia; Ronoh, Eunice; Jansen, Léon; Seidell, Jacob C

2011-01-01

INTRODUCTION: Nutrient profiling is defined as the science of categorising foods based on their nutrient composition. The Choices Programme is a nutrient profile system with criteria that determine whether foods are eligible to carry a "healthier option" stamp. The Daily Menu Method which has been

Recycling Lesson Plan

Science.gov (United States)

Okaz, Abeer Ali

2013-01-01

This lesson plan designed for grade 2 students has the goal of teaching students about the environmental practice of recycling. Children will learn language words related to recycling such as: "we can recycle"/"we can't recycle" and how to avoid littering with such words as: "recycle paper" and/or "don't throw…

Fluorescent lamp recycling initiatives in the United States and a recycling proposal based on extended producer responsibility and product stewardship concepts.

Science.gov (United States)

Silveira, Geraldo Tr; Chang, Shoou-Yuh

2011-06-01

This paper presents an overview of mercury-containing lamp (MCL) recycling initiatives currently available in the world, especially in the United States. The majority of MCLs contain mercury which is a neurotoxin, a persistent pollutant in the environment, and can bioaccumulate in the food chain. Although there are some recycling options in the United States, collection rates are still at 23% of all potential used MCLs. This shows that citizens are either indifferent to or unaware of the recycling alternatives. On the other hand, MCL recycling seems not to be a cost-effective process and, for this reason, in the United States, take-back programmes are still sponsored only by consumers or municipalities. A few retailers have recently initiated limited take-back alternatives and manufacturers have not yet supported financially any consistent recycling alternative in the country. Considering successful experiences, this paper makes a suggestion for an MCL recycling system based on the concepts of extended producer responsibility and product stewardship. A manufacturer-importer advance recycling fee is proposed to finance the collection and recycling system while a MCL-energy recycling fee supported by the energy sector creates a lamp refund process. 'PRO Lamp', a producer responsibility organization, will manage the entire system through a widespread public-private agreement.

Recovering valuable metals from recycled photovoltaic modules.

Science.gov (United States)

Yi, Youn Kyu; Kim, Hyun Soo; Tran, Tam; Hong, Sung Kil; Kim, Myong Jun

2014-07-01

Recovering valuable metals such as Si, Ag, Cu, and Al has become a pressing issue as end-of-life photovoltaic modules need to be recycled in the near future to meet legislative requirements in most countries. Of major interest is the recovery and recycling of high-purity silicon (> 99.9%) for the production of wafers and semiconductors. The value of Si in crystalline-type photovoltaic modules is estimated to be -$95/kW at the 2012 metal price. At the current installed capacity of 30 GW/yr, the metal value in the PV modules represents valuable resources that should be recovered in the future. The recycling of end-of-life photovoltaic modules would supply > 88,000 and 207,000 tpa Si by 2040 and 2050, respectively. This represents more than 50% of the required Si for module fabrication. Experimental testwork on crystalline Si modules could recover a > 99.98%-grade Si product by HNO3/NaOH leaching to remove Al, Ag, and Ti and other metal ions from the doped Si. A further pyrometallurgical smelting at 1520 degrees C using CaO-CaF2-SiO2 slag mixture to scavenge the residual metals after acid leaching could finally produce > 99.998%-grade Si. A process based on HNO3/NaOH leaching and subsequent smelting is proposed for recycling Si from rejected or recycled photovoltaic modules. Implications: The photovoltaic industry is considering options of recycling PV modules to recover metals such as Si, Ag, Cu, Al, and others used in the manufacturing of the PV cells. This is to retain its "green" image and to comply with current legislations in several countries. An evaluation of potential resources made available from PV wastes and the technologies used for processing these materials is therefore of significant importance to the industry. Of interest are the costs of processing and the potential revenues gained from recycling, which should determine the viability of economic recycling of PV modules in the future.

FY 1999 project on the development of new industry support type international standards. Standardization of a method to calculate recycling rates of automobile products; 1999 nendo shinki sangyo shiengata kokusai hyojun kaihatsu jigyo seika hokokusho. Jidosha seihin no recycle ritsu no santei hoho no hyojunka

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

For the purpose not only of solving the environmental problem but also of making effective use of resources and contributing to the appropriate treatment in the stage of the used resource, study was conducted of the standardization of a method to calculate recycle rates of automobile products. The FY 1999 results were summarized. In this fiscal year, to give definition of the recycle potentiality and thermal recycle, the following were proceeded with: trial evaluation of recycle potentiality, survey of the actual state of recycling of rubber/plastic parts, study of the requirements to realize the recycle potentiality, study of the requirements to realize the thermal recycle, and approaches to the international standardization. As to the trial evaluation of the recycle potentiality, tests to dismantle automobiles were made to assess the dismantlement, separation and recognition. The requirements to realize the recycle potentiality were studied. It was found out that few non-metallic materials are not recycled in the present situation. The paper studied what the requirements to realize the recycle potentiality and thermal recycle should be like basically since there is no recognition internationally unified. (NEDO)

Secondary resources and recycling in developing economies

International Nuclear Information System (INIS)

Raghupathy, Lakshmi; Chaturvedi, Ashish

2013-01-01

Recycling of metals extends the efficient use of minerals and metals, reduces pressure on environment and results in major energy savings in comparison to primary production. In developing economies recycling had been an integral part of industrial activity and has become a major concern due to the handling of potentially hazardous material without any regard to the occupational health and safety (OH and S) needs. With rising awareness and interest from policy makers, the recycling scenario is changing and the large scale enterprises are entering the recycling sector. There is widespread expectation that these enterprises would use the Best Available Technologies (BAT) leading to better environment management and enhanced resource recovery. The major challenge is to enhance and integrate the activities of other stakeholders in the value chain to make recycling an economically viable and profitable enterprise. This paper is an attempt to propose a sustainable model for recycling in the developing economies through integration of the informal and formal sectors. The main objective is to augment the existing practices using a scientific approach and providing better technology without causing an economic imbalance to the present practices. In this paper studies on lead acid batteries and e-waste recycling in India are presented to evolve a model for “green economy”

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.

Producer responsibility and recycling solar photovoltaic modules

International Nuclear Information System (INIS)

McDonald, N.C.; Pearce, J.M.

2010-01-01

Rapid expansion of the solar photovoltaic (PV) industry is quickly causing solar to play a growing importance in the energy mix of the world. Over the full life cycle, although to a smaller degree than traditional energy sources, PV also creates solid waste. This paper examines the potential need for PV recycling policies by analyzing existing recycling protocols for the five major types of commercialized PV materials. The amount of recoverable semiconductor material and glass in a 1 m 2 area solar module for the five types of cells is quantified both physically and the profit potential of recycling is determined. The cost of landfill disposal of the whole solar module, including the glass and semiconductor was also determined for each type of solar module. It was found that the economic motivation to recycle most PV modules is unfavorable without appropriate policies. Results are discussed on the need to regulate for appropriate energy and environmental policy in the PV manufacturing industry particularly for PV containing hazardous materials. The results demonstrate the need to encourage producer responsibility not only in the PV manufacturing sector but also in the entire energy industry.

Life cycle perspective on recycling of ashes; Livscykelperspektiv paa aatervinning av askor

Energy Technology Data Exchange (ETDEWEB)

Olsson, Susanna

2007-07-01

The purpose of this project was to, from a life cycle perspective, discuss the consequences of recycling or disposing combustion ashes. The aim was to regard regional as well as global environmental impacts and point at potential conflicts between different environmental objectives, in order to produce basic information for decision-making on criteria and regulations for ash handling.Three different ashes were studied: bottom ash from waste incineration, fly ash from combustion of peat and from forest fuels. For all ashes three different scenarios were studied, two where the ash is recycled, and one where it is disposed. Focus was put on the difference between the three scenarios during 100 years. The use of bottom ash from waste incineration for roads saved crushed rock and energy, but produced more leaching of metals than the disposal alternative. Using this ash in drainage strata saves sand but causes higher metal leaching too. The same conclusions can be drawn for fly ash from peat, here leaching of Arsenic is the main factor. Using the peat ash as road contraction material saves more resources than the use for drainage blankets. For forest fuel ash, both the use as road construction material and recycling to the forest saves resources and energy. Recycling to the forest saves most energy but also the resources of Zinc, Phosphorous and Dolomite. Leaching of metals is most important for the forest recycling, and the nature of this resource recycling can be argued. The results are most sensitive concerning transports and leaching, but also for maintenance of the constructions where the ash is used. For the forest fuel ash, the suppositions about the necessity of compensation for nutrients removed with the fuel, have important effects for the result. Generally it can be said, for all three cases, that the estimates of leaching of metals are very uncertain, and that there is a need to develop the existing models for long term leaching. The three cases demonstrated

Characterization and potential recycling of home building wood waste

Science.gov (United States)

Philip A. Araman; D.P. Hindman; M.F. Winn

2010-01-01

Construction waste represents a significant portion of landfill waste, estimated as 17% of the total waste stream. Wood construction waste of a 2000 square foot single family home we found to be 1500-3700 lbs of solid-sawn wood, and 1000-1800 lbs of engineered wood products (EWP). Much of the solid-sawn lumber and EWPs could be recycled into several products. Through a...

Comparison of actinides and fission products recycling scheme with the normal plutonium recycling scheme in fast reactors

Directory of Open Access Journals (Sweden)

Salahuddin Asif

2013-01-01

Full Text Available Multiple recycling of actinides and non-volatile fission products in fast reactors through the dry re-fabrication/reprocessing atomics international reduction oxidation process has been studied as a possible way to reduce the long-term potential hazard of nuclear waste compared to that resulting from reprocessing in a wet PUREX process. Calculations have been made to compare the actinides and fission products recycling scheme with the normal plutonium recycling scheme in a fast reactor. For this purpose, the Karlsruhe version of isotope generation and depletion code, KORIGEN, has been modified accordingly. An entirely novel fission product yields library for fast reactors has been created which has replaced the old KORIGEN fission products library. For the purposes of this study, the standard 26 groups data set, KFKINR, developed at Forschungszentrum Karlsruhe, Germany, has been extended by the addition of the cross-sections of 13 important actinides and 68 most important fission products. It has been confirmed that these 68 fission products constitute about 95% of the total fission products yield and about 99.5% of the total absorption due to fission products in fast reactors. The amount of fissile material required to guarantee the criticality of the reactor during recycling schemes has also been investigated. Cumulative high active waste per ton of initial heavy metal is also calculated. Results show that the recycling of actinides and fission products in fast reactors through the atomics international reduction oxidation process results in a reduction of the potential hazard of radioactive waste.

Recycling of sewage in Swedish municipalities - Policy implications

Energy Technology Data Exchange (ETDEWEB)

Soederberg, H

1998-12-31

The construction of sewage treatment plants, which increased dramatically during the sixties in Sweden, was based on the idea that sewage is a waste, despite the fact that it contains considerable amounts of nourishment. Environmental research today, focuses more and more on recycling and on the potential resource inherent in sewage. This chapter deals with how to manage a change from problem elimination to recycling of resources, and discuss such from an institutional perspective. A shift towards recycling implies a shift of techniques, decision-makers and process strategies. Implementation of recycling will need strategic principles, and thereby results from research focusing common property resource management can be used in the policy process 32 refs, 5 figs

Recycling of sewage in Swedish municipalities - Policy implications

Energy Technology Data Exchange (ETDEWEB)

Soederberg, H.

1997-12-31

The construction of sewage treatment plants, which increased dramatically during the sixties in Sweden, was based on the idea that sewage is a waste, despite the fact that it contains considerable amounts of nourishment. Environmental research today, focuses more and more on recycling and on the potential resource inherent in sewage. This chapter deals with how to manage a change from problem elimination to recycling of resources, and discuss such from an institutional perspective. A shift towards recycling implies a shift of techniques, decision-makers and process strategies. Implementation of recycling will need strategic principles, and thereby results from research focusing common property resource management can be used in the policy process 32 refs, 5 figs

Assessment of by-products of bioenergy systems (anaerobic digestion and gasification) as potential crop nutrient.

Science.gov (United States)

Kataki, Sampriti; Hazarika, Samarendra; Baruah, D C

2017-01-01

Alternative fertilizer resources have drawn attention in recent times in order to cope up with ever increasing demand for fertilizer. By-products of bioenergy system are considered favourable as organic fertilizer due to their ability to recycle plant nutrients. Present study evaluates fertilizer suitability of by-products of two bioenergy systems viz. 3 types of anaerobic digestion by-products (digestate) from local surplus biomass such as cowdung, Ipomoea carnea:cowdung (60:40) and ricestraw:green gram stover:cowdung (30:30:40) and one gasification by-product (biochar) from rice husk. Digestates were assessed considering 4 different application options of each viz. whole, solid, liquid and ash from solid digestates. Digestate characteristics (organic matter, macronutrients, micronutrients and heavy metal content) were found to be a function of feedstock and processing (solid liquid separation and ashing). Ipomoea carnea based digestates in all application options showed comparatively higher N, P, K, NH 4 + -N, Ca, Mg, S and micro nutrient content than other digestates. Separation concentrated plant nutrients and organic matter in solid digestates, making these suitable both as organic amendments and fertilizer. Separated liquid digestate shared larger fraction of ammonium nitrogen (61-91% of total content), indicating their suitability as readily available N source. However, fertilizer application of liquid digestate may not match crop requirements due to lower total nutrient concentration. Higher electrical conductivity of the liquid digestates (3.4-9.3mScm -1 ) than solid digestates (1.5-2mScm -1 ) may impart phyto-toxic effect upon fertilization due to salinity. In case of by-products with unstable organic fraction i.e. whole and solid digestates of rice straw:green gram stover:cowdung digestates (Humification index 0.7), further processing (stabilization, composting) may be required to maximize their fertilizer benefit. Heavy metal contents of the by

Implementation of UV-based advanced oxidation processes in algal medium recycling.

Science.gov (United States)

Wang, Wenxuan; Sha, Jun; Lu, Zhiying; Shao, Senlin; Sun, Peizhe; Hu, Qiang; Zhang, Xuezhi

2018-09-01

Algae show great potential as sustainable feedstock for numerous bioproducts. However, large volume of water consumption during algal biomass production makes that the culture media recycling is a necessity due to economic and environmental concern. To avoid the negative effect of enriched organic matters in the harvested culture media, pre-treatment prior to medium replenishment and reuse is required. In this study, degradation of algenitic organic matters (AOM) in the culture media by UV-based photolysis processes (i.e., direct UV, UV/peroxydisulfate (PDS), UV/H 2 O 2 , and UV/NH 2 Cl) was explored. The results showed that UV, UV/PDS, UV/H 2 O 2 and UV/NH 2 Cl caused a decrease of SUVA for 29.9%, 35.4%, 40.45%, and 22.6%, respectively, though the organic matter was almost not mineralized. Fluorescence excitation-emission matrix combined with parallel factor analysis indicated that UV/PDS and UV/H 2 O 2 degraded 47.26%-56.31% of the fulvic-like and humic-like fractions in AOM. Powder activated carbon absorption and growth evaluation for the AOPs-treated media indicated that UV/PDS and UV/H 2 O 2 processes not only could remove the growth inhibitors in the media, but were also beneficial to the algae growth. These results suggested that UV/PDS and UV/H 2 O 2 could effectively degrade the hydrophobic components in AOM and converted the growth inhibition fraction of AOM in the recycled media into nutrient source for algal growth. Different from the general application of UV-based AOP in the wastewater treatment, this study provided an innovative idea about how to pre-treat AOM in the media recycling: utilization rather than removal, which was a more sustainable and environment-friendly technology. Copyright © 2018 Elsevier B.V. All rights reserved.

RECYCLING OF WATER TREATMENT PLANT SLUDGE VIA LAND APPLICATION: ASSESSMENT OF RISK

Science.gov (United States)

Water treatment sludges (WTS) offer potential benefits when applied to soil and recycling of the waste stream via land application has been proposed as a management option. Recycling of WTS to the land helps conserve landfill disposal capacity and natural resources, but potential...

Defense Waste Processing Facility Recycle Stream Evaporation

International Nuclear Information System (INIS)

STONE, MICHAEL

2006-01-01

The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) stabilizes high level radioactive waste (HLW) by vitrification of the waste slurries. DWPF currently produces approximately five gallons of dilute recycle for each gallon of waste vitrified. This recycle stream is currently sent to the HLW tank farm at SRS where it is processed through the HLW evaporators with the concentrate eventually sent back to the DWPF for stabilization. Limitations of the HLW evaporators and storage space constraints in the tank farm have the potential to impact the operation of the DWPF and could limit the rate that HLW is stabilized. After an evaluation of various alternatives, installation of a dedicated evaporator for the DWPF recycle stream was selected for further evaluation. The recycle stream consists primarily of process condensates from the pretreatment and vitrification processes. Other recycle streams consist of process samples, sample line flushes, sump flushes, and cleaning solutions from the decontamination and filter dissolution processes. The condensate from the vitrification process contains some species, such as sulfate, that are not appreciably volatile at low temperature and could accumulate in the system if 100% of the evaporator concentrate was returned to DWPF. These species are currently removed as required by solids washing in the tank farm. The cleaning solutions are much higher in solids content than the other streams and are generated 5-6 times per year. The proposed evaporator would be required to concentrate the recycle stream by a factor of 30 to allow the concentrate to be recycled directly to the DWPF process, with a purge stream sent to the tank farm as required to prevent buildup of sulfate and similar species in the process. The overheads are required to meet stringent constraints to allow the condensate to be sent directly to an effluent treatment plant. The proposed evaporator would nearly de-couple the DWPF process from the

Advances in the understanding of nutrient dynamics and management in UK agriculture.

Science.gov (United States)

Dungait, Jennifer A J; Cardenas, Laura M; Blackwell, Martin S A; Wu, Lianhai; Withers, Paul J A; Chadwick, David R; Bol, Roland; Murray, Philip J; Macdonald, Andrew J; Whitmore, Andrew P; Goulding, Keith W T

2012-09-15

Current research on macronutrient cycling in UK agricultural systems aims to optimise soil and nutrient management for improved agricultural production and minimise effects on the environment and provision of ecosystem services. Nutrient use inefficiencies can cause environmental pollution through the release of greenhouse gases into the atmosphere and of soluble and particulate forms of N, P and carbon (C) in leachate and run-off into watercourses. Improving nutrient use efficiencies in agriculture calls for the development of sustainable nutrient management strategies: more efficient use of mineral fertilisers, increased recovery and recycling of waste nutrients, and, better exploitation of the substantial inorganic and organic reserves of nutrients in the soil. Long-term field experimentation in the UK has provided key knowledge of the main nutrient transformations in agricultural soils. Emerging analytical technologies, especially stable isotope labelling, that better characterise macronutrient forms and bioavailability and improve the quantification of the complex relationships between the macronutrients in soils at the molecular scale, are augmenting this knowledge by revealing the underlying processes. The challenge for the future is to determine the relationships between the dynamics of N, P and C across scales, which will require both new modelling approaches and integrated approaches to macronutrient cycling. Copyright © 2012 Elsevier B.V. All rights reserved.

Composition of waste materials and recyclables

DEFF Research Database (Denmark)

Götze, Ramona

involves several steps to prepare the samples mechanically and/or chemically for final analysis. Not all sample preparation methods are equally well suited for specific waste characterization purposes. The correctness of results and practical feasibility of sample preparation was strongly affected...... for future modelling and assessment of waste management systems. The analyzed fractions were selected based on material properties with relevance for potential recycling processes. The physico-chemical analysis revealed chemical differences between residual and source-segregated samples for several fractions....... The results for parameters associated with organic matter confirmed the idea of cross-contaminated recyclables in residual waste, whereas the results for heavy metals and trace elements were more complex. For many fractions rather high metal contents were found to be intrinsic properties of the recyclables...

Open-loop recycling: A LCA case study of PET bottle-to-fibre-recycling

NARCIS (Netherlands)

Shen, L.; Worrell, E.; Patel, M.K.

2010-01-01

This study assesses the environmental impact of polyethylene terephthalate (PET) bottle-to-fibre recycling using the methodology of life-cycle assessment (LCA). Four recycling cases, including mechanical recycling, semi-mechanical recycling, back-to-oligomer recycling and back-to-monomer recycling

Synaptic activity regulates AMPA receptor trafficking through different recycling pathways

Science.gov (United States)

Zheng, Ning; Jeyifous, Okunola; Munro, Charlotte; Montgomery, Johanna M; Green, William N

2015-01-01

Changes in glutamatergic synaptic strength in brain are dependent on AMPA-type glutamate receptor (AMPAR) recycling, which is assumed to occur through a single local pathway. In this study, we present evidence that AMPAR recycling occurs through different pathways regulated by synaptic activity. Without synaptic stimulation, most AMPARs recycled in dynamin-independent endosomes containing the GTPase, Arf6. Few AMPARs recycled in dynamin-dependent endosomes labeled by transferrin receptors (TfRs). AMPAR recycling was blocked by alterations in the GTPase, TC10, which co-localized with Arf6 endosomes. TC10 mutants that reduced AMPAR recycling had no effect on increased AMPAR levels with long-term potentiation (LTP) and little effect on decreased AMPAR levels with long-term depression. However, internalized AMPAR levels in TfR-containing recycling endosomes increased after LTP, indicating increased AMPAR recycling through the dynamin-dependent pathway with synaptic plasticity. LTP-induced AMPAR endocytosis is inconsistent with local recycling as a source of increased surface receptors, suggesting AMPARs are trafficked from other sites. DOI: http://dx.doi.org/10.7554/eLife.06878.001 PMID:25970033

Changes in the oligomerization potential of the division inhibitor UgtP co-ordinate Bacillus subtilis cell size with nutrient availability.

Science.gov (United States)

Chien, An-Chun; Zareh, Shannon Kian Gharabiklou; Wang, Yan Mei; Levin, Petra Anne

2012-11-01

How cells co-ordinate size with growth and development is a major, unresolved question in cell biology. In previous work we identified the glucosyltransferase UgtP as a division inhibitor responsible for increasing the size of Bacillus subtilis cells under nutrient-rich conditions. In nutrient-rich medium, UgtP is distributed more or less uniformly throughout the cytoplasm and concentrated at the cell poles and/or the cytokinetic ring. Under these conditions, UgtP interacts directly with FtsZ to inhibit division and increase cell size. Conversely, under nutrient-poor conditions, UgtP is sequestered away from FtsZ in punctate foci, and division proceeds unimpeded resulting in a reduction in average cell size. Here we report that nutrient-dependent changes in UgtP's oligomerization potential serve as a molecular rheostat to precisely co-ordinate B. subtilis cell size with nutrient availability. Our data indicate UgtP interacts with itself and the essential cell division protein FtsZ in a high-affinity manner influenced in part by UDP glucose, an intracellular proxy for nutrient availability. These findings support a model in which UDP-glc-dependent changes in UgtP's oligomerization potential shift the equilibrium between UgtP•UgtP and UgtP•FtsZ, fine-tuning the amount of FtsZ available for assembly into the cytokinetic ring and with it cell size. © 2012 Blackwell Publishing Ltd.

Secondary resources and recycling in developing economies.

Science.gov (United States)

Raghupathy, Lakshmi; Chaturvedi, Ashish

2013-09-01

Recycling of metals extends the efficient use of minerals and metals, reduces pressure on environment and results in major energy savings in comparison to primary production. In developing economies recycling had been an integral part of industrial activity and has become a major concern due to the handling of potentially hazardous material without any regard to the occupational health and safety (OH&S) needs. With rising awareness and interest from policy makers, the recycling scenario is changing and the large scale enterprises are entering the recycling sector. There is widespread expectation that these enterprises would use the Best Available Technologies (BAT) leading to better environment management and enhanced resource recovery. The major challenge is to enhance and integrate the activities of other stakeholders in the value chain to make recycling an economically viable and profitable enterprise. This paper is an attempt to propose a sustainable model for recycling in the developing economies through integration of the informal and formal sectors. The main objective is to augment the existing practices using a scientific approach and providing better technology without causing an economic imbalance to the present practices. In this paper studies on lead acid batteries and e-waste recycling in India are presented to evolve a model for "green economy". Copyright © 2013 Elsevier B.V. All rights reserved.

Using biochar in animal farming to recycle nutrients and reduce greenhouse gas emissions

Science.gov (United States)

Schmidt, Hans-Peter; Wilson, Kelpie; Kammann, Claudia

2017-04-01

Charcoal has been used to treat digestive disorder in animals since several thousand years. But only since about 2010 biochar has increasingly been used as regular feed additive in animal farming usually mixed with standard feed at approximately 1% of the daily feed intake. The use of biochar as feed additive has the potential to improve animal health, feed efficiency and the animal-stable environment; to reduce nutrient losses and GHG emissions; and to increase soil organic mater and thus soil fertility. The evaluation of more than 150 scientific papers on feeding (activated) biochar showed in most of the studies and for all investigated livestock species positive effects on parameters like toxin adsorption, digestion, blood values, feed use efficiency and livestock weight gain, meat quality and GHG emissions. The facilitation of direct electron transfers between different species of bacteria or microbial consortia via the biochar mediator in the animal digestion tract is hypothesized to be the main reason for a more energy efficient digestion and thus higher feed efficiency, for its selective probiotic effect, for reduced N-losses and eventually for less GHG emissions. While chicken, pigs, fish and other omnivore animals provoke GHG-emissions (mainly NH3, CH4, N2O) when their liquid and solid excretions decompose anaerobically, ruminants cause direct methane emissions through flatulence and burps (eructation). Preliminary studies demonstrated that feeding high temperature biochars might reduce ruminant CH4 emissions though more systematic research is needed. It is likely that microbial decomposition of manure containing digested biochar produces less ammonia, less methane and thus retain more nitrogen, as seen when manure was composted with and without biochar or when biochar is used as bedding or manure treatment additive. Laboratory adsorption trials estimated that using biochar for liquid manure treatment could safe 57,000 t NH4 and 4,600 t P2O5 fertilizer per

Behaviour of Recycled Coarse Aggregate Concrete: Age and Successive Recycling

Science.gov (United States)

Sahoo, Kirtikanta; Pathappilly, Robin Davis; Sarkar, Pradip

2016-06-01

Recycled Coarse Aggregate (RCA) concrete construction technique can be called as `green concrete', as it minimizes the environmental hazard of the concrete waste disposal. Indian standard recommends target mean compressive strength of the conventional concrete in terms of water cement ratio ( w/ c). The present work is an attempt to study the behaviour of RCA concrete from two samples of parent concrete having different age group with regard to the relationship of compressive strength with water cement ratios. Number of recycling may influence the mechanical properties of RCA concrete. The influence of age and successive recycling on the properties such as capillary water absorption, drying shrinkage strain, air content, flexural strength and tensile splitting strength of the RCA concrete are examined. The relationship between compressive strength at different w/ c ratios obtained experimentally is investigated for the two parameters such as age of parent concrete and successive recycling. The recycled concrete using older recycled aggregate shows poor quality. While the compressive strength reduces with successive recycling gradually, the capillary water absorption increases abruptly, which leads to the conclusion that further recycling may not be advisable.

Assessment of municipal solid waste generation and recyclable materials potential in Kuala Lumpur, Malaysia.

Science.gov (United States)

Saeed, Mohamed Osman; Hassan, Mohd Nasir; Mujeebu, M Abdul

2009-07-01

This paper presents a forecasting study of municipal solid waste generation (MSWG) rate and potential of its recyclable components in Kuala Lumpur (KL), the capital city of Malaysia. The generation rates and composition of solid wastes of various classes such as street cleansing, landscape and garden, industrial and constructional, institutional, residential and commercial are analyzed. The past and present trends are studied and extrapolated for the coming years using Microsoft office 2003 Excel spreadsheet assuming a linear behavior. The study shows that increased solid waste generation of KL is alarming. For instance, the amount of daily residential SWG is found to be about 1.62 kg/capita; with the national average at 0.8-0.9 kg/capita and is expected to be increasing linearly, reaching to 2.23 kg/capita by 2024. This figure seems reasonable for an urban developing area like KL city. It is also found that, food (organic) waste is the major recyclable component followed by mix paper and mix plastics. Along with estimated population growth and their business activities, it has been observed that the city is still lacking in terms of efficient waste treatment technology, sufficient fund, public awareness, maintaining the established norms of industrial waste treatment etc. Hence it is recommended that the concerned authority (DBKL) shall view this issue seriously.

Variable nutrient stoichiometry (carbon:nitrogen:phosphorus) across trophic levels determines community and ecosystem properties in an oligotrophic mangrove system.

Science.gov (United States)

Scharler, U M; Ulanowicz, R E; Fogel, M L; Wooller, M J; Jacobson-Meyers, M E; Lovelock, C E; Feller, I C; Frischer, M; Lee, R; McKee, K; Romero, I C; Schmit, J P; Shearer, C

2015-11-01

Our study investigated the carbon:nitrogen:phosphorus (C:N:P) stoichiometry of mangrove island of the Mesoamerican Barrier Reef (Twin Cays, Belize). The C:N:P of abiotic and biotic components of this oligotrophic ecosystem was measured and served to build networks of nutrient flows for three distinct mangrove forest zones (tall seaward fringing forest, inland dwarf forests and a transitional zone). Between forest zones, the stoichiometry of primary producers, heterotrophs and abiotic components did not change significantly, but there was a significant difference in C:N:P, and C, N, and P biomass, between the functional groups mangrove trees, other primary producers, heterotrophs, and abiotic components. C:N:P decreased with increasing trophic level. Nutrient recycling in the food webs was highest for P, and high transfer efficiencies between trophic levels of P and N also indicated an overall shortage of these nutrients when compared to C. Heterotrophs were sometimes, but not always, limited by the same nutrient as the primary producers. Mangrove trees and the primary tree consumers were P limited, whereas the invertebrates consuming leaf litter and detritus were N limited. Most compartments were limited by P or N (not by C), and the relative depletion rate of food sources was fastest for P. P transfers thus constituted a bottleneck of nutrient transfer on Twin Cays. This is the first comprehensive ecosystem study of nutrient transfers in a mangrove ecosystem, illustrating some mechanisms (e.g. recycling rates, transfer efficiencies) which oligotrophic systems use in order to build up biomass and food webs spanning various trophic levels.

Variable nutrient stoichiometry (carbon:nitrogen:phosphorus) across trophic levels determines community and ecosystem properties in an oligotrophic mangrove system

Science.gov (United States)

Scharler, U.M.; Ulanowicz, Robert E.; Fogel, M.L.; Wooller, M.J.; Jacobson-Meyers, M.E.; Lovelock, C.E.; Feller, I.C.; Frischer, M.; Lee, R.; Mckee, Karen L.; Romero, I.C.; Schmit, J.P.; Shearer, C.

2015-01-01

Our study investigated the carbon:nitrogen:phosphorus (C:N:P) stoichiometry of mangrove island of the Mesoamerican Barrier Reef (Twin Cays, Belize). The C:N:P of abiotic and biotic components of this oligotrophic ecosystem was measured and served to build networks of nutrient flows for three distinct mangrove forest zones (tall seaward fringing forest, inland dwarf forests and a transitional zone). Between forest zones, the stoichiometry of primary producers, heterotrophs and abiotic components did not change significantly, but there was a significant difference in C:N:P, and C, N, and P biomass, between the functional groups mangrove trees, other primary producers, heterotrophs, and abiotic components. C:N:P decreased with increasing trophic level. Nutrient recycling in the food webs was highest for P, and high transfer efficiencies between trophic levels of P and N also indicated an overall shortage of these nutrients when compared to C. Heterotrophs were sometimes, but not always, limited by the same nutrient as the primary producers. Mangrove trees and the primary tree consumers were P limited, whereas the invertebrates consuming leaf litter and detritus were N limited. Most compartments were limited by P or N (not by C), and the relative depletion rate of food sources was fastest for P. P transfers thus constituted a bottleneck of nutrient transfer on Twin Cays. This is the first comprehensive ecosystem study of nutrient transfers in a mangrove ecosystem, illustrating some mechanisms (e.g. recycling rates, transfer efficiencies) which oligotrophic systems use in order to build up biomass and food webs spanning various trophic levels.

Assessment studies on plutonium recycle in CANDU reactors

International Nuclear Information System (INIS)

1978-11-01

This paper describes the CANDU reactor system in detail and goes on to explore the potential for using the system with plutonium recycle fuelling to improve fuel utilisation and to meet the long-term challenge of economic supplies of nuclear fuel. The paper includes comments on costs and non-proliferation aspects. It concludes that: recycle fuelling is feasible with little modification to the reactor design and no degradation of safety, and could offer over 50% savings in uranium requirements. However, recycle fuelling costs do not appear competitive with natural uranium in the CANDU system under current economic conditions

Addressing Criticality in Rare Earth Elements via Permanent Magnets Recycling

Science.gov (United States)

Nlebedim, I. C.; King, A. H.

2018-02-01

Rare earth elements (REEs) are critical for many advanced technologies and are faced with potential supply disruptions. Recycling of permanent magnets (PMs) can be good sources for REEs which can help minimize global dependence on freshly mined REEs, but PMs are rarely recycled. Recycling of PMs has been discussed with respect to improving REEs resource sustainability. Some challenges to be addressed in order to establish industrially deployable technologies for PMs recycling have also been discussed, including profitability, energy efficiency and environmental impacts. Key considerations for promoting circular economy via PMs recycling is proposed with the focus on deciding the target points in the supply chain at which the recycled products will be inserted. Important technical considerations for recycling different forms of waste PMs, including swarfs, slags, shredded and intact hard disk drives magnets, have been presented. The aspects of circular economy considered include reusing magnets, remanufacturing magnets and recovering of REEs from waste PMs.

Recycling of plastics in Germany

International Nuclear Information System (INIS)

Thienen, N. von; Patel, M.

1999-01-01

This article deals with the waste management of post-consumer plastics in Germany and its potential to save fossil fuels and reduce CO 2 emissions. Since most experience is available for packaging, the paper first gives an overview of the legislative background and the material flows for this sector. Then recycling and recovery processes for plastics waste from all sectors are assessed in terms of their contribution to energy saving and CO 2 abatement. Practically all the options studied show a better performance than waste treatment in an average incinerator which has been chosen as the reference case. High ecological benefits can be achieved by mechanical recycling if virgin polymers are substituted. The paper then presents different scenarios for managing plastic waste in Germany in 1995: considerable savings can be made by strongly enhancing the efficiency of waste incinerators. Under these conditions the distribution of plastics waste among mechanical recycling, feedstock recycling and energy recovery has a comparatively mall impact on the overall results. The maximum savings amount to 74 PJ of energy, i.e, 9% of the chemical sector energy demand in 1995 and 7.0 Mt CO 2 , representing 13% of the sector's emissions. The assessment does not support a general recommendation of energy recovery due to the large difference between the German average and the best available municipal waste-to-energy facilities and also due to new technological developments in the field of mechanical recycling

Structural and functional characteristics of buffer strip vegetation in an agricultural landscape - high potential for nutrient removal but low potential for plant biodiversity.

Science.gov (United States)

Hille, Sandra; Andersen, Dagmar Kappel; Kronvang, Brian; Baattrup-Pedersen, Annette

2018-07-01

Vegetated buffer strips constitute a transition zone between terrestrial and aquatic ecosystems and provide several ecosystem services. Buffer strips are often applied as a mitigation measure against diffuse pollution in agricultural areas, primarily because they may retain nutrients and in this way help protect the aquatic environment. Additionally, they can improve biodiversity in an otherwise homogenous landscape and may therefore have a value in their own right. In the present study, we characterized the structural and functional features of the vegetation in Danish buffer strips using a nationwide dataset to explore: i) their floristic quality in terms of species diversity and conservation value and ii) based on their functional characteristics, their potential to retain nutrients. Moreover, we analyzed how the structural and functional characteristics varied along gradients in the environmental features of the catchment. We found that the floristic quality of the buffer vegetation was generally low, exhibiting an average of only 3.3% of the number of species of conservation interest. Instead, Danish buffer strips were dominated by widespread and productive species that are tolerant of anthropogenic impacts in the catchment. The abundance of highly productive plant species was positively related to high intensity land use, whereas the abundance of stress-tolerant plant species was positively related to low intensity land use. The high productivity of the buffer strips implies a large bio-storage potential, and these areas might therefore offer an opportunity to remove nutrients by harvesting the plant biomass. We discuss how Danish buffer strips could be exploited via appropriate management (e.g. harvesting) to maximize nutrient retention and at the same time improve floristic quality. Copyright © 2018 Elsevier B.V. All rights reserved.

Technical evaluation of a tank-connected food waste disposer system for biogas production and nutrient recovery.

Science.gov (United States)

Davidsson, Å; Bernstad Saraiva, A; Magnusson, N; Bissmont, M

2017-07-01

In this study, a tank-connected food waste disposer system with the objective to optimise biogas production and nutrient recovery from food waste in Malmö was evaluated. The project investigated the source-separation ratio of food waste through waste composition analyses, determined the potential biogas production in ground food waste, analysed the organic matter content and the limiting components in ground food waste and analysed outlet samples to calculate food waste losses from the separation tank. It can be concluded that the tank-connected food waste disposer system in Malmö can be used for energy recovery and optimisation of biogas production. The organic content of the collected waste is very high and contains a lot of energy rich fat and protein, and the methane potential is high. The results showed that approximately 38% of the food waste dry matter is collected in the tank. The remaining food waste is either found in residual waste (34% of the dry matter) or passes the tank and goes through the outlet to the sewer (28%). The relatively high dry matter content in the collected fraction (3-5% DM) indicates that the separation tank can thicken the waste substantially. The potential for nutrient recovery is rather limited considering the tank content. Only small fractions of the phosphorus (15%) and nitrogen (21%) are recyclable by the collected waste in the tank. The quality of the outlet indicates a satisfactory separation of particulate organic matter and fat. The organic content and nutrients, which are in dissolved form, cannot be retained in the tank and are rather led to the sewage via the outlet. Copyright © 2017 Elsevier Ltd. All rights reserved.

Recycling cellulases for cellulosic ethanol production at industrial relevant conditions: potential and temperature dependency at high solid processes.

Science.gov (United States)

Lindedam, Jane; Haven, Mai Østergaard; Chylenski, Piotr; Jørgensen, Henning; Felby, Claus

2013-11-01

Different versions of two commercial cellulases were tested for their recyclability of enzymatic activity at high dry matter processes (12% or 25% DM). Recyclability was assessed by measuring remaining enzyme activity in fermentation broth and the ability of enzymes to hydrolyse fresh, pretreated wheat straw. Industrial conditions were used to study the impact of hydrolysis temperature (40 or 50°C) and residence time on recyclability. Enzyme recycling at 12% DM indicated that hydrolysis at 50°C, though ideal for ethanol yield, should be kept short or carried out at lower temperature to preserve enzymatic activity. Best results for enzyme recycling at 25% DM was 59% and 41% of original enzyme load for a Celluclast:Novozyme188 mixture and a modern cellulase preparation, respectively. However, issues with stability of enzymes and their strong adsorption to residual solids still pose a challenge for applicable methods in enzyme recycling. Copyright © 2013 Elsevier Ltd. All rights reserved.

Efficient way back litters nutrient potential of a tropical forest of bank. Sierra Nevada of Santa Marta Colombia

International Nuclear Information System (INIS)

Fuentes Molina, Natalia; Rodriguez Barrios, Javier Alfredo

2012-01-01

In three representative forests along the River Gaira, (subtropical wet forest, subtropical moist forest and tropical thorn mount), were measured over six months (wet and dry seasons) fluxes of nitrogen and phosphorus through the litter. Concentrations of nutrients (nitrogen and phosphorus) in the litter were relatively similar in the three Nevada de Santa Marta Colombia. Fuentes, Rodriguez. vegetation types (1.71% n and 0.12% p for the subtropical moist forest, followed by the tropical thorn mount with 1.50% n and 0.10% p and the subtropical wet forest with 1.39% n and 0.08% p), with the most significant differences found for nitrogen, which is the major nutrient with the absolute maximum in the subtropical rain forest set in the middle stretch of the basin. The greatest returns on biomass and nutrients occurred in the subtropical moist forest and tropical thorn mount set in the middle and lower reaches of the basin. The leaves showed high concentration of n and consequently, given the high production values of the different fractions, a high potential return of n (78.6 kg ha-1 yr-1). The foliar p concentration showed a potential return of 4.9 kgha1yr-1 and high values of the indices of efficiency in their use (iev: 2888.5) and foliar resorption (ern: 98.2), was the nutrient most limiting.

PROPERTIES AND MICROSTRUCTURE OF CEMENT PASTE INCLUDING RECYCLED CONCRETE POWDER

Directory of Open Access Journals (Sweden)

Jaroslav Topič

2017-02-01

Full Text Available The disposal and further recycling of concrete is being investigated worldwide, because the issue of complete recycling has not yet been fully resolved. A fundamental difficulty faced by researchers is the reuse of the recycled concrete fines which are very small (< 1 mm. Currently, full recycling of such waste fine fractions is highly energy intensive and resulting in production of CO2. Because of this, the only recycling methods that can be considered as sustainable and environmentally friendly are those which involve recycled concrete powder (RCP in its raw form. This article investigates the performance of RCP with the grain size < 0.25 mm as a potential binder replacement, and also as a microfiller in cement-based composites. Here, the RCP properties are assessed, including how mechanical properties and the microstructure are influenced by increasing the amount of the RCP in a cement paste (≤ 25 wt%.

Optical absorption in recycled waste plastic polyethylene

Science.gov (United States)

Aji, M. P.; Rahmawati, I.; Priyanto, A.; Karunawan, J.; Wati, A. L.; Aryani, N. P.; Susanto; Wibowo, E.; Sulhadi

2018-03-01

We investigated the optical properties of UV spectrum absorption in recycled waste plastic from polyethylene polymer type. Waste plastic polyethylene showed an optical spectrum absorption after it’s recycling process. Spectrum absorption is determined using spectrophotometer UV-Nir Ocean Optics type USB 4000. Recycling method has been processed using heating treatment around the melting point temperature of the polyethylene polymer that are 200°C, 220°C, 240°C, 260°C, and 280°C. In addition, the recycling process was carried out with time variations as well, which are 1h, 1.5h, 2h, and 2.5h. The result of this experiment shows that recycled waste plastic polyethylene has a spectrum absorption in the ∼ 340-550 nm wavelength range. The absorbance spectrum obtained from UV light which is absorbed in the orbital n → π* and the orbital π → π*. This process indicates the existence of electron transition phenomena. This mechanism is affected by the temperature and the heating time where the intensity of absorption increases and widens with the increase of temperature and heating time. Furthermore this study resulted that the higher temperature affected the enhancement of the band gap energy of waste plastic polyethylene. These results show that recycled waste plastic polyethylene has a huge potential to be absorber materials for solar cell.

Recycling issues facing target and RTL materials of inertial fusion designs

International Nuclear Information System (INIS)

El-Guebaly, L.; Wilson, P.; Sawan, M.; Henderson, D.; Varuttamaseni, A.

2005-01-01

Designers of heavy ion (HI) and Z-pinch inertial fusion power plants have explored the potential of recycling the target and recyclable transmission line (RTL) materials as an alternate option to disposal in a geological repository. This work represents the first time a comprehensive recycling assessment was performed on both machines with an exact pulse history. Our results offer two divergent conclusions on the recycling issue. For the HI concept, target recycling is not a 'must' requirement and the preferred option is the one-shot use scenario as target materials represent a small waste stream, less than 1% of the total nuclear island waste. We recommend using low-cost hohlraum materials once-through and then disposing of them instead of recycling expensive materials such as Au and Gd. On the contrary, RTL recycling is a 'must' requirement for the Z-pinch concept in order to minimize the RTL inventory and enhance the economics. The RTLs meet the low level waste and recycling dose requirements with a wide margin when recycled for the entire plant life even without a cooling period. While recycling offers advantages to the Z-pinch system, it adds complexity and cost to the HI designs

Japanese Fast Reactor Program for Homogeneous Actinide Recycling

International Nuclear Information System (INIS)

Ishikawa, Makoto; Nagata, Takashi; Kondo, Satoru

2008-01-01

In the present report, the homogeneous actinide recycling scenario of Fast Reactor (FR) Cycle Technology Development Project (FaCT) is summarized. First, the scenario of nuclear energy policy in Japan are briefly reviewed. Second, the basic plan of Japan to manage all minor actinide (MA) by recycling is summarized objectives of which are the efficiency increase of uranium resources, the environmental burden reduction, and the increase of nuclear non-proliferation potential. Third, recent results of reactor physics study related to MA-loaded FR cores are briefly described. Fourth, typical nuclear design of MA-loaded FR cores in the FaCT project and their main features are demonstrated with the feasibility to recycle all MA in the future FR equilibrium society. Finally, the research and development program to realize the MA recycling in Japan is introduced, including international cooperation projects. (authors)

Compatibilization of recycled polypropylene and recycled poly (ethylene terephthalate blends with SEBS-g-MA

Directory of Open Access Journals (Sweden)

Luciana Maria Guadagnini Araujo

2018-03-01

Full Text Available Abstract The compatibilization of recycled PP/PET blend with high and low concentration (20 and 5 phr of elastomer functionalized by maleic anhydride (SEBS-g-MA was achieved. Recycled polypropylene from plastic industry and recycled PET from post-consumer bottles was used. PP/PET blends: 80:20 w/w, 50:50 w/w and 20:80 w/w were prepared in an internal mixer for mechanical properties, thermal properties, morphology and rheological properties. SEBS-g-MA promoted compatibilization of the PP/PET blends and improved their properties. With an increasing compatibilization level, the refinement of morphology was observed in the PET rich blend. Compatibilized blends showed negative deviation in the PET glass transition temperature related to neat PET, demonstrating that compatibilization was very successful. PET crystallization was accelerated in the blends due to PP presence that enhanced nucleation. It was found that the 50/50/20 blend showed huge potential for textile fiber application and that of 80/20/20 showed more intermediary properties than neat polymers.

Exploring the Nutrient Release Potential of Organic Materials as Integrated Soil Fertility Management Components Using SAFERNAC

NARCIS (Netherlands)

Maro, G.P.; Mrema, J.P.; Msanya, B.M.; Janssen, B.H.; Teri, J.M.

2014-01-01

The aim of this study was to establish the nutrient release potential of different organic materials and assess their role in integrated soil fertility management for coffee using the new coffee yield model SAFERNAC. It involved an incubation experiment conducted at TaCRI Lyamungu Screenhouse for

Suitability of untreated wood ash for recycling; Qualitaet und Verwertungsmoeglichkeiten von Holzaschen aus naturbelassenen Hoelzern

Energy Technology Data Exchange (ETDEWEB)

Stahl, E. [Fraunhofer-Inst. fuer Umwelt-, Sicherheits- und Energietechnik, UMSICHT, Oberhausen (Germany); Doetsch, P. [RWTH Aachen (Germany). Lehr- und Forschungsgebiet Abfallwirtschaft

2008-10-15

Background, aim and scope: The increasing use of wood for generating heat and electricity requires that more and more fuels be obtained directly or indirectly from the forest. Sound, sustainable recycling management calls for the return of any generated wood ash back to the forest to make use of the nutrients it contains. Similarly, recycling this ash in other locations such as agricultural land or private gardens can serve equally well as fertilizer. At the same time, it is critical that no accumulated pollutants be introduced into the nutrient loop. Wood ash that is heavily laden with such pollutants must not be considered for recycling. As part of this research project, commissioned by the Ministry for the Environment and Conservation, Agriculture and Consumer Protection of the State of North Rhine-Westphalia in Germany (MUNLV), ash samples of 209 woodfired appliances generating between 10 and 4000 kW of heat performance were taken from throughout the federal state of North Rhine-Westphalia. Untreated wood, either forested or scrap, was used as the sole fuel for these appliances. Materials and methods: All course ash and fly ash samples were analyzed to determine their composition of main nutrients, heavy metals, and the elements Fe, Cl, Si, Al and Na. The purpose of this analysis was to evaluate the suitability of this wood ash for reintroduction to forest soils or as fertilizer in other types of soil. Results: The majority of the wood ash samples in this study contained sufficiently high amounts of nutrients to match the requirement for stand-alone fertilizers (PK-fertilizer, potash fertilizer). However, the heavy metal content was highly variable, with a mean content high enough to prohibit them from being classified per se as PK- or potash fertilizer for agricultural land. Due to the high quantities of cadmium, application of this ash to garden soils would likewise be ill-advised. Discussion: On forest soils German law permits application of a mixture of

17. Meeting municipal waste Magdeburg. Residual waste - recycling - resource; 17. Tagung Siedlungsabfallwirtschaft Magdeburg. Restabfall - Recycling - Ressource

Energy Technology Data Exchange (ETDEWEB)

Haase, Hartwig (ed.)

2012-11-01

Within the 17th meeting Waste Management at Residential Areas from 12th o 13th September, 2012 in Magdeburg (Federal Republic of Germany), the following lectures were held: (1) Opening Session - Waste management in Saxony-Anhalt (O. Aeikens); (2) World with future - the eco-social perspective (F.J. Radermacher); (3) Global commodity markets - rare earths and their recycling (I. Fahimi); (4) The further development of nearhousehold capture of recyclable materials (J. Seitel); (5) On the future of the disposal management (J. Balg); (6) Options for action for the future of the municipal waste management (A. Gosten); (7) Current models of the capture of recyclable materials in Germany (M. Kerkhoff); (8) The recycling bin as a pilot test in Hanover (R. Middendorf); (9) Position of BellandVision on the implementation of a unified recycling bin (J. Soelling); (10) What will change with the new Recycle Economy Law according to the material flows and waste treatment capacities? (H. Alwast); (11) Waste management plan Saxony-Anhalt - Current developments (S. Hagel); (12) Wastes from the thermal waste treatment - Risk potential and disposal (G.-R. Behr); (13) Landfill Mining - Contribution of the waste management to the securing of resources (K. Fricke); (14) Logistic process design and system design in the transport of wastes in developing countries using Serbia as an example (Z. Jovanovic); (15) Example of good practices in the subsequent use of landfills - Solar park Cracauer Anger (M. Harnack); (16) Ecoloop - energy efficient gasification in the limestone moving-bed (R. Moeller); (17) Utilization of waste and biomass as a resource? Only by means of an intelligent logistics. (S. Trojahn); (18) Renewable energy resources - Experiences of a network provider (J. Kempmann).

Excretion is Faster Than Diagenesis for Nutrient Recycling in Lake Michigan Benthos

Science.gov (United States)

Aguilar, C.; Cuhel, R. L.

2013-12-01

Regeneration of phytoplankton growth nutrients including ammonium (NH4+) and phosphate (HPO4=) occurs in aquatic systems worldwide through biogeochemical processes of diagenesis. Organic matter falling to the bottom accumulates in sediments, and bacterial decomposition removes oxygen from the sub-surface. Anaerobic metabolism is energetically inefficient, and bacteria a few cm below the surface respire or ferment organic matter into carbon dioxide or organic acids, excreting nitrogen (NH4+) or phosphorus inorganic 'waste'. Subsurface production of bacterial metabolic products often leads to sharp gradients in porewater concentrations of NH4+ and HPO4=, which drive diffusive flux out of the sediments into overlying water. Aquatic systems with totally aerobic water overlying anoxic sediment (e.g., Lake Michigan) have muted efflux of certain inorganic nutrients arising from organic matter decomposition. For example, NH4+ is oxidized to nitrate in the upper few mm of surficial sediments by nitrifying bacteria. Strong subsurface porewater gradients, especially of redox- or geochemically-reactive compounds, often decline to low values well below the sediment-water interface, indicating transformation by sediment bacterial populations, or by purely geochemical processes such as calcium hydroxyphosphate (apatite) precipitation. For these, little flux to the water column occurs. In Lake Michigan, neither NH4+ nor HPO4= escapes substantially from the biogeochemical barriers between their diagenetic sources and overlying waters, either before or after ecosystem alteration by invasive quagga mussels (QM). Silicate and total CO2 evade unimpeded in the same cores. The organic matter deposited from the water column is also the nutrition of benthic bivalve filter feeders such as QM in Lake Michigan, or the Asian Clam in San Francisco Bay. In animal metabolism for energy production, only the carbon component is oxidized through respiration, with NH4+ (from protein) and HPO4= (from

A critical assessment of the ecological assumptions underpinning compensatory mitigation of salmon-derived nutrients

Science.gov (United States)

Collins, Scott F.; Marcarelli, Amy M.; Baxter, Colden V.; Wipfli, Mark S.

2015-01-01

We critically evaluate some of the key ecological assumptions underpinning the use of nutrient replacement as a means of recovering salmon populations and a range of other organisms thought to be linked to productive salmon runs. These assumptions include: (1) nutrient mitigation mimics the ecological roles of salmon, (2) mitigation is needed to replace salmon-derived nutrients and stimulate primary and invertebrate production in streams, and (3) food resources in rearing habitats limit populations of salmon and resident fishes. First, we call into question assumption one because an array of evidence points to the multi-faceted role played by spawning salmon, including disturbance via redd-building, nutrient recycling by live fish, and consumption by terrestrial consumers. Second, we show that assumption two may require qualification based upon a more complete understanding of nutrient cycling and productivity in streams. Third, we evaluate the empirical evidence supporting food limitation of fish populations and conclude it has been only weakly tested. On the basis of this assessment, we urge caution in the application of nutrient mitigation as a management tool. Although applications of nutrients and other materials intended to mitigate for lost or diminished runs of Pacific salmon may trigger ecological responses within treated ecosystems, contributions of these activities toward actual mitigation may be limited.

Reuse potential of laundry greywater for irrigation based on growth, water and nutrient use of tomato

Science.gov (United States)

Misra, R. K.; Patel, J. H.; Baxi, V. R.

2010-05-01

SummaryGreywater is considered as a valuable resource with a high reuse potential for irrigation of household lawns and gardens. However, there are possibilities of surfactant and sodium accumulation in soil from reuse of greywater which may affect agricultural productivity and environmental sustainability adversely. We conducted a glasshouse experiment to examine variation in growth, water and nutrient use of tomato ( Lycopersicon esculentum Mill. cv. Grosse Lisse) using tap water (TW), laundry greywater (GW) and solutions of low and high concentration of a detergent surfactant (LC and HC, respectively) as irrigation treatments. Each treatment was replicated five times using a randomised block design. Measurements throughout the experiment showed greywater to be significantly more alkaline and saline than the other types of irrigation water. Although all plants received 16 irrigations over a period of 9 weeks until flowering, there were little or no significant effects of irrigation treatments on plant growth. Soil water retention following irrigation reduced significantly when plants were irrigated with GW or surfactant solutions on only three of 12 occasions. On one occasion, water use measured as evapotranspiration (ET) with GW irrigation was similar to TW, but it was significantly higher than the plants receiving HC irrigation. At harvest, various components of plant biomass and leaf area for GW irrigated plants were found to be similar or significantly higher than the TW irrigated plants with a common trend of GW ⩾ TW > LC ⩾ HC. Whole-plant concentration was measured for 12 essential plant nutrients (N, P, K, Ca, Mg, S, Fe, Cu, Mn, Zn, Mo and B) and Na (often considered as a beneficial nutrient). Irrigation treatments affected the concentration of four nutrients (P, Fe, Zn and Na) and uptake of seven nutrients (P, K, Ca, Mg, Na, Fe and B) significantly. Uptake of these seven nutrients by tomato was generally in the order GW ⩾ TW > HC ⩾ LC. GW

Optimal policies for aggregate recycling from decommissioned forest roads.

Science.gov (United States)

Thompson, Matthew; Sessions, John

2008-08-01

To mitigate the adverse environmental impact of forest roads, especially degradation of endangered salmonid habitat, many public and private land managers in the western United States are actively decommissioning roads where practical and affordable. Road decommissioning is associated with reduced long-term environmental impact. When decommissioning a road, it may be possible to recover some aggregate (crushed rock) from the road surface. Aggregate is used on many low volume forest roads to reduce wheel stresses transferred to the subgrade, reduce erosion, reduce maintenance costs, and improve driver comfort. Previous studies have demonstrated the potential for aggregate to be recovered and used elsewhere on the road network, at a reduced cost compared to purchasing aggregate from a quarry. This article investigates the potential for aggregate recycling to provide an economic incentive to decommission additional roads by reducing transport distance and aggregate procurement costs for other actively used roads. Decommissioning additional roads may, in turn, result in improved aquatic habitat. We present real-world examples of aggregate recycling and discuss the advantages of doing so. Further, we present mixed integer formulations to determine optimal levels of aggregate recycling under economic and environmental objectives. Tested on an example road network, incorporation of aggregate recycling demonstrates substantial cost-savings relative to a baseline scenario without recycling, increasing the likelihood of road decommissioning and reduced habitat degradation. We find that aggregate recycling can result in up to 24% in cost savings (economic objective) and up to 890% in additional length of roads decommissioned (environmental objective).

Bacterial Active Community Cycling in Response to Solar Radiation and Their Influence on Nutrient Changes in a High-Altitude Wetland.

Science.gov (United States)

Molina, Verónica; Hernández, Klaudia; Dorador, Cristina; Eissler, Yoanna; Hengst, Martha; Pérez, Vilma; Harrod, Chris

2016-01-01

Microbial communities inhabiting high-altitude spring ecosystems are subjected to extreme changes in solar irradiance and temperature throughout the diel cycle. Here, using 16S rRNA gene tag pyrosequencing (cDNA) we determined the composition of actively transcribing bacteria from spring waters experimentally exposed through the day (morning, noon, and afternoon) to variable levels of solar radiation and light quality, and evaluated their influence on nutrient recycling. Solar irradiance, temperature, and changes in nutrient dynamics were associated with changes in the active bacterial community structure, predominantly by Cyanobacteria, Verrucomicrobia, Proteobacteria, and 35 other Phyla, including the recently described Candidate Phyla Radiation (e.g., Parcubacteria, Gracilibacteria, OP3, TM6, SR1). Diversity increased at noon, when the highest irradiances were measured (3.3-3.9 H', 1125 W m -2 ) compared to morning and afternoon (0.6-2.8 H'). This shift was associated with a decrease in the contribution to pyrolibraries by Cyanobacteria and an increase of Proteobacteria and other initially low frequently and rare bacteria phyla (solar radiation. In addition, the percentage contribution of cyanobacterial sequences in the afternoon was similar to those recorded in the morning. The shifts in the contribution by Cyanobacteria also influenced the rate of change in nitrate, nitrite, and phosphate, highlighted by a high level of nitrate accumulation during hours of high radiation and temperature associated with nitrifying bacteria activity. We did not detect ammonia or nitrite oxidizing bacteria in situ , but both functional groups ( Nitrosomona and Nitrospira ) appeared mainly in pyrolibraries generated from dark incubations. In total, our results reveal that both the structure and the diversity of the active bacteria community was extremely dynamic through the day, and showed marked shifts in composition that influenced nutrient recycling, highlighting how abiotic

Rethink, Rework, Recycle.

Science.gov (United States)

Wrhen, Linda; DiSpezio, Michael A.

1991-01-01

Information about the recycling and reuse of plastics, aluminum, steel, glass, and newspapers is presented. The phases of recycling are described. An activity that allows students to separate recyclable materials is included. The objectives, a list of needed materials, and procedure are provided. (KR)

Recycling at Penn State's Beaver Stadium. "Recycle on the Go" Success Story

Science.gov (United States)

US Environmental Protection Agency, 2009

2009-01-01

With a 13-year-old recycling program, The Pennsylvania State University's (Penn State) Beaver Stadium in the past diverted nearly 30 tons of recyclables per year from local landfills. A new initiative to promote recycling in the stadium's tailgating area has helped Penn State more than triple its old recycling record, collecting 112 tons in 2008.…

Recycling of waste bread as culture media for efficient biological treatment of wastewater

International Nuclear Information System (INIS)

Kim, Young-Ju; Kim, Pil-Jin; Kim, Ji-Hoon; Lee, Chang-Soo; Qureshi, T.I.

2012-01-01

Possibilities of recycling of waste bread as culture media for efficient biological treatment of wastewater were investigated. In order to get the highest growth of microorganism for increased contaminants' removal efficiency of the system, different compositions of waste bread and skim milk with and without adding Powdered Activated Carbon (PAC) were tested. Mixed waste bread compositions with added PAC showed relatively higher number of microorganisms than the compositions without added PAC. A composition of 40% mixed waste bread and 60% skim milk produced highest number of microorganisms with subsequent increased contaminants' removal efficiency of the system. 'Contrast' alone showed lower contaminants' removal efficiency than mixed bread compositions. Use of waste bread in the composition of skim milk reduced cost of using foreign source of nutrients in biological treatment of wastewater and also facilitated waste bread management through recycling. (author)

Nutrient production from dairy cattle manure and loading on arable land

Directory of Open Access Journals (Sweden)

Seunggun Won

2017-01-01

Full Text Available Objective Along with increasing livestock products via intensive rearing, the accumulation of livestock manure has become a serious issue due to the fact that there is finite land for livestock manure recycling via composting. The nutrients from livestock manure accumulate on agricultural land and the excess disembogues into streams causing eutrophication. In order to systematically manage nutrient loading on agricultural land, quantifying the amount of nutrients according to their respective sources is very important. However, there is a lack of research concerning nutrient loss from livestock manure during composting or storage on farms. Therefore, in the present study we quantified the nutrients from dairy cattle manure that were imparted onto agricultural land. Methods Through investigation of 41 dairy farms, weight reduction and volatile solids (VS, total nitrogen (TN, and total phosphorus (TP changes of dairy cattle manure during the storage and composting periods were analyzed. In order to support the direct investigation and survey on site, the three cases of weight reduction during the storing and composting periods were developed according to i experiment, ii reference, and iii theoretical changes in phosphorus content (ΔP = 0. Results The data revealed the nutrient loading coefficients (NLCs of VS, TN, and TP on agricultural land were 1.48, 0.60, and 0.66, respectively. These values indicated that the loss of nitrogen and phosphorus was 40% and 34%, respectively, and that there was an increase of VS since bedding materials were mixed with excretion in the barn. Conclusion As result of nutrient-footprint analyses, the amounts of TN and TP particularly entered on arable land have been overestimated if applying the nutrient amount in fresh manure. The NLCs obtained in this study may assist in the development of a database to assess the accurate level of manure nutrient loading on soil and facilitate systematic nutrient management.

Recycling of electronic scrap

DEFF Research Database (Denmark)

Legarth, Jens Brøbech

This Ph.D. thesis deals with the growingly important field of electronics recycling with special attention to the problem of printed circuit board recycling. A literature survey of contemporary electronics recycling and printed circuit board recycling is presented.Further, an analysis of the role...

Effects of forest fuels extraction (whole tree harvesting) and ash recycling, experience and results from Swedish research

International Nuclear Information System (INIS)

Westling, Olle; Egnell, Gustaf; Dahlberg, Anders

2005-01-01

This review of Swedish research and environmental assessment studies during more than a decade is based on an ongoing synthesis of long term experiments with whole tree harvesting and wood ash recycling and other relevant research. The review is focused on effects of whole tree harvesting and compensatory fertilisation (wood ash) on forest production, biodiversity and soil and surface water. The studied extraction of biofuels (logging residues) from forest is primarily a complement to the conventional harvest of pulpwood and timber. General conclusions are that a large part of the theoretical potential of extraction of logging residues, in the form of branches and tops, can be utilised on condition that the losses of nutrients and acid neutralising capacity are compensated for through nutrient addition. To protect valuable fauna and flora, biotopes where conventional forestry is presently not applied should, with some exceptions, not be utilised for extraction of biofuels. The usage of wood ashes and other fertilisers will not increase the net accumulation of heavy metals and toxic organic elements in the forest ecosystems, on condition that the concentrations are low in the fertilisers

Modelling Recycling Targets

DEFF Research Database (Denmark)

hill, amanda; Leinikka Dall, Ole; Andersen, Frits Møller

2014-01-01

% for household waste, and sets an ambitious goal of a 50% recycling rate by 2020. This study integrates the recycling target into the FRIDA model to project how much waste and from which streams should be diverted from incineration to recycling in order to achieve the target. Furthermore, it discusses how...

Recycling production designs: the value of coordination and flexibility in aluminum recycling operations

Science.gov (United States)

Brommer, Tracey H.

The growing motivation for aluminum recycling has prompted interest in recycling alternative and more challenging secondary materials. The nature of these alternative secondary materials necessitates the development of an intermediate recycling facility that can reprocess the secondary materials into a liquid product Two downstream aluminum remelters will incorporate the liquid products into their aluminum alloy production schedules. Energy and environmental benefits result from delivering the products as liquid but coordination challenges persist because of the energy cost to maintain the liquid. Further coordination challenges result from the necessity to establish a long term recycling production plan in the presence of long term downstream aluminum remelter production uncertainty and inherent variation in the daily order schedule of the downstream aluminum remelters. In this context a fundamental question arises, considering the metallurgical complexities of dross reprocessing, what is the value of operating a coordinated set of by-product reprocessing plants and remelting cast houses? A methodology is presented to calculate the optimal recycling center production parameters including 1) the number of recycled products, 2) the volume of recycled products, 3) allocation of recycled materials across recycled products, 4) allocation of recycled products across finished alloys, 4) the level of flexibility for the recycling center to operate. The methods implemented include, 1) an optimization model to describe the long term operations of the recycling center, 2) an uncertainty simulation tool, 3) a simulation optimization method, 4) a dynamic simulation tool with four embedded daily production optimization models of varying degrees of flexibility. This methodology is used to quantify the performance of several recycling center production designs of varying levels of coordination and flexibility. This analysis allowed the identification of the optimal recycling

The Life Cycle Cost (LCC) of Life Support Recycling and Resupply

Science.gov (United States)

Jones, Harry W.

2015-01-01

Brief human space missions supply all the crew's water and oxygen from Earth. The multiyear International Space Station (ISS) program instead uses physicochemical life support systems to recycle water and oxygen. This paper compares the Life Cycle Cost (LCC) of recycling to the LCC of resupply for potential future long duration human space missions. Recycling systems have high initial development costs but relatively low durationdependent support costs. This means that recycling is more cost effective for longer missions. Resupplying all the water and oxygen requires little initial development cost but has a much higher launch mass and launch cost. The cost of resupply increases as the mission duration increases. Resupply is therefore more cost effective than recycling for shorter missions. A recycling system pays for itself when the resupply LCC grows greater over time than the recycling LCC. The time when this occurs is called the recycling breakeven date. Recycling will cost very much less than resupply for long duration missions within the Earth-Moon system, such as a future space station or Moon base. But recycling would cost about the same as resupply for long duration deep space missions, such as a Mars trip. Because it is not possible to provide emergency supplies or quick return options on the way to Mars, more expensive redundant recycling systems will be needed.

Concrete produced with recycled aggregates

Directory of Open Access Journals (Sweden)

J. J. L. Tenório

Full Text Available This paper presents the analysis of the mechanical and durable properties of recycled aggregate concrete (RAC for using in concrete. The porosity of recycled coarse aggregates is known to influence the fresh and hardened concrete properties and these properties are related to the specific mass of the recycled coarse aggregates, which directly influences the mechanical properties of the concrete. The recycled aggregates were obtained from construction and demolition wastes (CDW, which were divided into recycled sand (fine and coarse aggregates. Besides this, a recycled coarse aggregate of a specific mass with a greater density was obtained by mixing the recycled aggregates of the CDW with the recycled aggregates of concrete wastes (CW. The concrete was produced in laboratory by combining three water-cement ratios, the ratios were used in agreement with NBR 6118 for structural concretes, with each recycled coarse aggregates and recycled sand or river sand, and the reference concrete was produced with natural aggregates. It was observed that recycled aggregates can be used in concrete with properties for structural concrete. In general, the use of recycled coarse aggregate in combination with recycled sand did not provide good results; but when the less porous was used, or the recycled coarse aggregate of a specific mass with a greater density, the properties of the concrete showed better results. Some RAC reached bigger strengths than the reference concrete.

Sustainable recycling technologies for Solar PV off-grid system

Science.gov (United States)

Uppal, Bhavesh; Tamboli, Adish; Wubhayavedantapuram, Nandan

2017-11-01

Policy makers throughout the world have accepted climate change as a repercussion of fossil fuel exploitation. This has led the governments to integrate renewable energy streams in their national energy mix. PV off-grid Systems have been at the forefront of this transition because of their permanently increasing efficiency and cost effectiveness. These systems are expected to produce large amount of different waste streams at the end of their lifetime. It is important that these waste streams should be recycled because of the lack of available resources. Our study found that separate researches have been carried out to increase the efficiencies of recycling of individual PV system components but there is a lack of a comprehensive methodical research which details efficient and sustainable recycling processes for the entire PV off-grid system. This paper reviews the current and future recycling technologies for PV off-grid systems and presents a scheme of the most sustainable recycling technologies which have the potential for adoption. Full Recovery End-of-Life Photovoltaic (FRELP) recycling technology can offer opportunities to sustainably recycle crystalline silicon PV modules. Electro-hydrometallurgical process & Vacuum technologies can be used for recovering lead from lead acid batteries with a high recovery rate. The metals in the WEEE can be recycled by using a combination of biometallurgical technology, vacuum metallurgical technology and other advanced metallurgical technologies (utrasonical, mechano-chemical technology) while the plastic components can be effectively recycled without separation by using compatibilizers. All these advanced technologies when used in combination with each other provide sustainable recycling options for growing PV off-grid systems waste. These promising technologies still need further improvement and require proper integration techniques before implementation.

Green Science: Revisiting Recycling

Science.gov (United States)

Palliser, Janna

2011-01-01

Recycling has been around for a long time--people have reused materials and refashioned them into needed items for thousands of years. More recently, war efforts encouraged conservation and reuse of materials, and in the 1970s recycling got its official start when recycling centers were created. Now, curbside recycling programs and recycling…

Solid waste composition analysis and recycling evaluation: Zaatari Syrian Refugees Camp, Jordan.

Science.gov (United States)

Saidan, Motasem N; Drais, Ammar Abu; Al-Manaseer, Ehab

2017-03-01

There is a need for Municipal Solid Waste (MSW) stream characterization and composition analysis to allow for an accurate estimation of its recycling potential and for effective management of the entire system. Recycling provides employment and a livelihood for vulnerable social groups such as refugees. The aim of this paper is to determine the composition of MSW in Zaatari Syrian Refugee Camp, where approximately 430,000 Syrian refugees have passed through the camp. The representative waste samples and analysis included household waste and commercial waste produced by the refugees in the selected districts in Zaatari. The waste sampling was performed in 2015 over two seasons to ensure that the seasonal fluctuations in the composition of the waste stream are taken into consideration. Hand sorting was used for classifying the collected wastes into the categories and subcategories. The organic waste represents the main waste category with 53% of the total MSW, while plastics, textile, and paper and cardboard are 12.85%, 10.22% and 9%, respectively. Moreover, the MSW composition percentage in Zaatari Camp is similar to that in municipalities in Jordan with slight disparity. The potential recyclable materials market has been investigated in this study. Plastics and paper and cardboard have significant potential to be separated and collected for recycling purposes. Financial revenues of potential recyclables have been analyzed based on local prices. Recycling model in the camp is also proposed based on the present study findings. Consequently, these results should be taken as a baseline for all Syrian refugees camps in the Middle East, as well as, in Europe. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of filtration and distillation methods for recycling automotive coolant

International Nuclear Information System (INIS)

Randall, P.M.; Gavaskar, A.R.

1992-01-01

Government regulations and high waste disposal cost of spent automotive coolant have driven the vehicle maintenance industry to explore on-site recycling. The USEPA in cooperation with the New Jersey Department of Environmental Protection (NJDEP) and the New Jersey Department of Transportation (NJDOT) evaluated two commercially available technologies that have potential for reducing the volume of spent automotive coolant. The objective of this study was to evaluate the quality of the recycled coolant, the pollution prevention potential, and the economic feasibility of the technologies

Nuclear fuel cycle waste recycling technology deverlopment - Radioactive metal waste recycling technology development

International Nuclear Information System (INIS)

Oh, Won Zin; Moon, Jei Kwon; Jung, Chong Hun; Park, Sang Yoon

1998-08-01

With relation to recycling of the radioactive metal wastes which are generated during operation and decommissioning of nuclear facilities, the following were described in this report. 1. Analysis of the state of the art on the radioactive metal waste recycling technologies. 2. Economical assessment on the radioactive metal waste recycling. 3. Process development for radioactive metal waste recycling, A. Decontamination technologies for radioactive metal waste recycling. B. Decontamination waste treatment technologies, C. Residual radioactivity evaluation technologies. (author). 238 refs., 60 tabs., 79 figs

Recycling of construction and demolition waste in Kuwait

International Nuclear Information System (INIS)

Kartam, N.; Al-Mutairi, N.; Al-Ghusain, I.; Al-Humoud, J.

2002-01-01

'Full text:' There is an increasing pressure on the construction industry to reduce costs and improve our environment. The fact is that both of these goals can be achieved at the same time. Although construction and demolition (C and D) constitutes a major type of waste in terms of volume and weight, its management and recycling efforts have not seen the light in Kuwait. The goal of this research project is to study methods leading to the minimization of the total C and D waste that is landfilled in Kuwait. This can be achieved by applying the waste management hierarchy in order of importance: 1) reduce, 2) re-use, 3) recycle, 4) incineration (energy recovery), and 5) safe disposal. This paper presents the current C and D waste disposal system in Kuwait and identifies potential problems to the environment, people and economy. Then, it investigates the recycling option to manage and control this major type of waste in an economically efficient and environmentally safe manner. There are significant volumes of potentially valuable and recoverable resources being wasted in the construction industry, and these figures are continuously growing as we are starting the new millennium. C and D waste constitutes 15%-30% of all solid waste entering landfills in various countries [Bossink 1995]; and thus it is a major type of waste. An estimated 2-3 million ton of construction and demolition waste are being only disposed of in Kuwait's landfill sites each year despite the limited available land (Industrial Investment Company, 1990). C and D waste is a target because it is both heavy and bulky, and therefore undesirable for disposal in engineered, lined landfills because of the space it consumes. On the other hand, many C and D materials have high potential for recovery and use. Recovering C and D waste can help communities reach their recycling goals, preserve valuable space in their local landfills, and create better opportunities for handling other kind of waste. Therefore

Chemical absorption and CO2 biofixation via the cultivation of Spirulina in semicontinuous mode with nutrient recycle.

Science.gov (United States)

da Rosa, Gabriel Martins; Moraes, Luiza; Cardias, Bruna Barcelos; de Souza, Michele da Rosa Andrade Zimmermann; Costa, Jorge Alberto Vieira

2015-09-01

The chemical absorption of carbon dioxide (CO2) is a technique used for the mitigation of the greenhouse effect. However, this process consumes high amounts of energy to regenerate the absorbent and to separate the CO2. CO2 removal by microalgae can be obtained via the photosynthesis process. The objective of this study was to investigate the cultivation and the macromolecules production by Spirulina sp. LEB 18 with the addition of monoethanolamine (MEA) and CO2. In the cultivation with MEA, were obtained higher results of specific growth rate, biomass productivity, CO2 biofixation, CO2 use efficiency, and lower generation time. Besides this, the carbohydrate concentration obtained at the end of this assay was approximately 96.0% higher than the control assay. Therefore, Spirulina can be produced using medium recycle and the addition of MEA, thereby promoting the reduction of CO2 emissions and showing potential for areas that require higher concentrations of carbohydrates, such as in bioethanol production. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Brazil Eucalyptus Potential Productivity Project: Influence of water, nutrients and stand uniformity on wood production

Science.gov (United States)

Jose Luiz Stape; Dan Binkley; Michael G. Ryan; Sebastiao Fonseca; Rodolfo A. Loos; Ernesto N. Takahashi; Claudio R. Silva; Sergio R. Silva; Rodrigo E. Hakamada; Jose Mario de A. Ferreira; Augusto M. N. Lima; Jose Luiz Gava; Fernado P. Leite; Helder B. Andrade; Jacyr M. Alves; Gualter G. C. Silva; Moises R. Azevedo

2010-01-01

We examined the potential growth of clonal Eucalyptus plantations at eight locations across a 1000+ km gradient in Brazil by manipulating the supplies of nutrients and water, and altering the uniformity of tree sizes within plots. With no fertilization or irrigation, mean annual increments of stem wood were about 28% lower (16.2 Mg...

The fast-recycling receptor Megalin defines the apical recycling pathway of epithelial cells

Science.gov (United States)

Perez Bay, Andres E.; Schreiner, Ryan; Benedicto, Ignacio; Paz Marzolo, Maria; Banfelder, Jason; Weinstein, Alan M.; Rodriguez-Boulan, Enrique J.

2016-01-01

The basolateral recycling and transcytotic pathways of epithelial cells were previously defined using markers such as transferrin (TfR) and polymeric IgA (pIgR) receptors. In contrast, our knowledge of the apical recycling pathway remains fragmentary. Here we utilize quantitative live-imaging and mathematical modelling to outline the recycling pathway of Megalin (LRP-2), an apical receptor with key developmental and renal functions, in MDCK cells. We show that, like TfR, Megalin is a long-lived and fast-recycling receptor. Megalin enters polarized MDCK cells through segregated apical sorting endosomes and subsequently intersects the TfR and pIgR pathways at a perinuclear Rab11-negative compartment termed common recycling endosomes (CRE). Whereas TfR recycles to the basolateral membrane from CRE, Megalin, like pIgR, traffics to subapical Rab11-positive apical recycling endosomes (ARE) and reaches the apical membrane in a microtubule- and Rab11-dependent manner. Hence, Megalin defines the apical recycling pathway of epithelia, with CRE as its apical sorting station. PMID:27180806

Continental crustal formation and recycling: Evidence from oceanic basalts

Science.gov (United States)

Saunders, A. D.; Tarney, J.; Norry, M. J.

1988-01-01

Despite the wealth of geochemical data for subduction-related magma types, and the clear importance of such magmas in the creation of continental crust, there is still no concensus about the relative magnitudes of crustal creation versus crustal destruction (i.e., recycling of crust into the mantle). The role of subducted sediment in the formation of the arc magmas is now well documented; but what proportion of sediment is taken into the deeper mantle? Integrated isotopic and trace element studies of magmas erupted far from presently active subduction zones, in particular basaltic rocks erupted in the ocean basins, are providing important information about the role of crustal recycling. By identifying potential chemical tracers, it is impossible to monitor the effects of crustal recycling, and produce models predicting the mass of material recycled into the mantle throughout long periods of geological time.

Direct Solid-State Conversion of Recyclable Metals and Alloys

Energy Technology Data Exchange (ETDEWEB)

Feng, Z; Manchiraju, K [Southwire Co.

2012-02-22

This project is to develop and demonstrate the concept feasibility of a highly energy-efficient solid-state material synthesis process, friction stir extrusion (FSE) technology. Specifically, the project seeks to explore and demonstrate the feasibility to recycle metals, produce nano-particle dispersion strengthened bulk materials and/or nano-composite materials from powders, chips or other recyclable feedstock metals or scraps through mechanical alloying and thermo-mechanical processing in a single-step. In this study, we focused on metal recycling, producing nano-engineered wires and evaluating their potential use in future generation long-distance electric power delivery infrastructure. More comprehensive R&D on the technology fundamentals and system scale-up toward early-stage applications in two targeted “showcase” fields of use: nano engineered bulk materials and Al recycling will be considered and planned as part of Project Continuation Plan.

Gamma radiation and osmotic potential of the nutrient solution differentially affect macronutrient concentrations, pH and EC in chilhuacle pepper fruits

International Nuclear Information System (INIS)

Victor Garcia-Gaytan, Libia Iris Trejo-Tellez; Olga Tejeda-Sartorius; Maribel Ramirez-Martinez; Julian Delgadillo-Martinez; Fernando Carlos Gomez-Merino; Soledad Garcia-Morales

2018-01-01

Chilhuacle pepper (Capsicum annuum L.) seeds were exposed to gamma radiation (GR) doses (0, 10, 80 and 120 Gy), and plants were grown in hydroponics with different osmotic potentials (OP) (- 0.036, - 0.072, - 0.092, and - 0.108 MPa) in the nutrient solution. We measured the nutrient concentrations, pH and electrical conductivity (EC) in fruits at different time points after transplanting (70, 90 and 130 dat), and found the GR, nutrient solution OP and their interactions differentially affected N, P, K, Ca, and Mg concentrations, as well as pH and EC in chilhuacle peppers. (author)

Recycling of plastic waste: Presence of phthalates in plastics from households and industry.

Science.gov (United States)

Pivnenko, K; Eriksen, M K; Martín-Fernández, J A; Eriksson, E; Astrup, T F

2016-08-01

Plastics recycling has the potential to substitute virgin plastics partially as a source of raw materials in plastic product manufacturing. Plastic as a material may contain a variety of chemicals, some potentially hazardous. Phthalates, for instance, are a group of chemicals produced in large volumes and are commonly used as plasticisers in plastics manufacturing. Potential impacts on human health require restricted use in selected applications and a need for the closer monitoring of potential sources of human exposure. Although the presence of phthalates in a variety of plastics has been recognised, the influence of plastic recycling on phthalate content has been hypothesised but not well documented. In the present work we analysed selected phthalates (DMP, DEP, DPP, DiBP, DBP, BBzP, DEHP, DCHP and DnOP) in samples of waste plastics as well as recycled and virgin plastics. DBP, DiBP and DEHP had the highest frequency of detection in the samples analysed, with 360μg/g, 460μg/g and 2700μg/g as the maximum measured concentrations, respectively. Among other, statistical analysis of the analytical results suggested that phthalates were potentially added in the later stages of plastic product manufacturing (labelling, gluing, etc.) and were not removed following recycling of household waste plastics. Furthermore, DEHP was identified as a potential indicator for phthalate contamination of plastics. Close monitoring of plastics intended for phthalates-sensitive applications is recommended if recycled plastics are to be used as raw material in production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Wastewater use in agriculture and potential effects on meso and macrofauna soil

Directory of Open Access Journals (Sweden)

Dinéia Tessaro

2016-06-01

Full Text Available ABSTRACT: The use of wastewater in agriculture has been practiced on an increasing scale over the past decades because of its fertilizing potential and the reduction in demand for surface water and groundwater. However, this practice may bring harm when performed without planning, not respecting the capacity of the soil to recycle organic waste. The most common problems are contamination of surface and groundwater via leaching and runoff, as well as accumulation of nutrients and potentially polluting elements that compromise chemical, physical and biological characteristics of the soil. The biological compartment, represented by the micro, meso and macrofauna, plays an important role in nutrient cycling, decomposition of organic matter, particle movement and transport of materials at different depths, helping to maintain soil physical and chemical characteristics. In this sense, this paper aims to discuss the effect of using different kinds of wastewater in agriculture on soil biology, highlighting strengths and weaknesses, as well as emphasizing the need to conduct investigations that enhance the positive aspects of wastewater use associated with edaphic processes.

Potential for the use of hydrochloric acid in fission reactor fuel recycle

International Nuclear Information System (INIS)

Mailen, J.C.; Bell, J.T.

1985-01-01

The chemistry and the effects of the use of hydrochloric acid as the aqueous phase in fuel recycle are surveyed. Available data are sufficient to suggest that separations of actinides and fission products can be at least as good in an HCl-trialkyl amine system as in Purex. Advantages of the HCl system are simpler operations of the off-gas system, better separation of neptunium from uranium and plutonium, better control of oxidation states of the dissolved species, and simpler recycle of the acid. A possible advantage is the more complete dissolution of the fission products, leaving very little insoluble residue. Disadvantages include lack of development of methods for dissolution of oxide fuel in hydrochloric acid, the requirement for processing equipment constructed of titanium, possible complications in the waste-handling system, and the dissolution of much of the cladding in the case of stainless-steel clad fuel

Recycling of plastic waste: Presence of phthalates in plastics from households and industry

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Eriksen, Marie Kampmann; Martín-Fernández, J. A.

2016-01-01

Plastics recycling has the potential to substitute virgin plastics partially as a source of raw materials in plastic product manufacturing. Plastic as a material may contain a variety of chemicals, some potentially hazardous. Phthalates, for instance, are a group of chemicals produced in large...... recognised, the influence of plastic recycling on phthalate content has been hypothesised but not well documented. In the present work we analysed selected phthalates (DMP, DEP, DPP, DiBP, DBP, BBzP, DEHP, DCHP and DnOP) in samples of waste plastics as well as recycled and virgin plastics. DBP, DiBP and DEHP...

Usage of Recycled Pet

Directory of Open Access Journals (Sweden)

A. Ebru Tayyar

2010-01-01

Full Text Available The increasing industrialization, urbanization and the technological development have caused to increase depletion of the natural resources and environmental pollution's problem. Especially, for the countries which have not enough space recycling of the waste eliminating waste on regular basis or decreasing the amount and volume of waste have provided the important advantages. There are lots of studies and projects to develop both protect resources and prevent environmental pollution. PET bottles are commonly used in beverage industry and can be reused after physical and chemical recycling processes. Usage areas of recycled PET have been developed rapidly. Although recycled PET is used in plastic industry, composite industry also provides usage alternatives of recycled PET. Textile is a suitable sector for recycling of some plastics made of polymers too. In this study, the recycling technologies and applications of waste PET bottles have been investigated and scientific works in this area have been summarized.

Nutrient cycle benchmarks for earth system land model

Science.gov (United States)

Zhu, Q.; Riley, W. J.; Tang, J.; Zhao, L.

2017-12-01

Projecting future biosphere-climate feedbacks using Earth system models (ESMs) relies heavily on robust modeling of land surface carbon dynamics. More importantly, soil nutrient (particularly, nitrogen (N) and phosphorus (P)) dynamics strongly modulate carbon dynamics, such as plant sequestration of atmospheric CO2. Prevailing ESM land models all consider nitrogen as a potentially limiting nutrient, and several consider phosphorus. However, including nutrient cycle processes in ESM land models potentially introduces large uncertainties that could be identified and addressed by improved observational constraints. We describe the development of two nutrient cycle benchmarks for ESM land models: (1) nutrient partitioning between plants and soil microbes inferred from 15N and 33P tracers studies and (2) nutrient limitation effects on carbon cycle informed by long-term fertilization experiments. We used these benchmarks to evaluate critical hypotheses regarding nutrient cycling and their representation in ESMs. We found that a mechanistic representation of plant-microbe nutrient competition based on relevant functional traits best reproduced observed plant-microbe nutrient partitioning. We also found that for multiple-nutrient models (i.e., N and P), application of Liebig's law of the minimum is often inaccurate. Rather, the Multiple Nutrient Limitation (MNL) concept better reproduces observed carbon-nutrient interactions.

Sustainable recycling technologies for Solar PV off-grid system

Directory of Open Access Journals (Sweden)

Uppal Bhavesh

2017-01-01

Full Text Available Policy makers throughout the world have accepted climate change as a repercussion of fossil fuel exploitation. This has led the governments to integrate renewable energy streams in their national energy mix. PV off-grid Systems have been at the forefront of this transition because of their permanently increasing efficiency and cost effectiveness. These systems are expected to produce large amount of different waste streams at the end of their lifetime. It is important that these waste streams should be recycled because of the lack of available resources. Our study found that separate researches have been carried out to increase the efficiencies of recycling of individual PV system components but there is a lack of a comprehensive methodical research which details efficient and sustainable recycling processes for the entire PV off-grid system. This paper reviews the current and future recycling technologies for PV off-grid systems and presents a scheme of the most sustainable recycling technologies which have the potential for adoption. Full Recovery End-of-Life Photovoltaic (FRELP recycling technology can offer opportunities to sustainably recycle crystalline silicon PV modules. Electro-hydrometallurgical process & Vacuum technologies can be used for recovering lead from lead acid batteries with a high recovery rate. The metals in the WEEE can be recycled by using a combination of biometallurgical technology, vacuum metallurgical technology and other advanced metallurgical technologies (utrasonical, mechano-chemical technology while the plastic components can be effectively recycled without separation by using compatibilizers. All these advanced technologies when used in combination with each other provide sustainable recycling options for growing PV off-grid systems waste. These promising technologies still need further improvement and require proper integration techniques before implementation.

Burden of industrial waste and potential for recycling: technological, economic and environmental aspects

Directory of Open Access Journals (Sweden)

Mihajlović Ivan

2017-07-01

Full Text Available Many benefits resulting from the development of the heavy industry are, unfortunately, accompanied by many issues resulting from the process of generating the industrial waste. This manuscript is presenting the environmental consequences, resulting from long period of time of heavy industry production and exploring the possibilities to recycle some of the industrial waste generated during the period of more than one century of ore excavation and copper extraction in the region of Eastern Serbia, in the vicinity of city of Bor. First part of the manuscript is presenting the scope of environmental issues, resulting from the heavy industry in this region and the amounts and the structure of the industrial waste, generated in this area, as well as the influence of generated waste to the environment of the region. Second part of the manuscript is dealing with the potential to recycle and reuse some of this waste, analyzing technological, economic and environmental aspects at the same time. In the final segment of the paper, some practical examples will be addressed based on the research work conducted at both experimental and industrial level. Results presented in the manuscript are mostly collected during long term research of the project team from Technical faculty in Bor, University of Belgrade, in the field of environmental management. This way, this manuscript is based on review of the research papers authored or co-authored by the author of this work, dealing with water, soil and air pollution, published in leading international journals. Also, the manuscript is presenting the literature review of other international issues dealing with the environmental management issues in the vicinity of large industrial complexes. Parts of the research results, presented in this manuscript are financially supported by the Ministry of Education, Science and Technological development of Republic of Serbia, under the project TR34023.

Plant growth and mineral recycle trade-offs in different scenarios for a CELSS. [Closed Ecological Life Support System

Science.gov (United States)

Ballou, E. V.; Wydeven, T.; Spitze, L. A.

1982-01-01

Data for hydroponic plant growth in a manned system test is combined with nutritional recommendations to suport trade-off calculations for closed and partially closed life support system scenarios. Published data are used as guidelines for the masses of mineral nutrients needed for higher plant production. The results of calculations based on various scenarios are presented for various combinations of plant growth chamber utilization and fraction of mineral recycle. Estimates are made of the masses of material needed to meet human nutritional requirements in the various scenarios. It appears that food production from a plant growth chamber with mineral recycle is favorable to reduction of the total launch weight in missions exceeding 3 years.

Quantifying nutrient uptake as driver of rock weathering in forest ecosystems by magnesium stable isotopes

Directory of Open Access Journals (Sweden)

D. Uhlig

2017-06-01

Full Text Available Plants and soil microbiota play an active role in rock weathering and potentially couple weathering at depth with erosion at the soil surface. The nature of this coupling is still unresolved because we lacked means to quantify the passage of chemical elements from rock through higher plants. In a temperate forested landscape characterised by relatively fast (∼ 220 t km−2 yr−1 denudation and a kinetically limited weathering regime of the Southern Sierra Critical Zone Observatory (SSCZO, California, we measured magnesium (Mg stable isotopes that are sensitive indicators of Mg utilisation by biota. We find that Mg is highly bio-utilised: 50–100 % of the Mg released by chemical weathering is taken up by forest trees. To estimate the tree uptake of other bio-utilised elements (K, Ca, P and Si we compared the dissolved fluxes of these elements and Mg in rivers with their solubilisation fluxes from rock (rock dissolution flux minus secondary mineral formation flux. We find a deficit in the dissolved fluxes throughout, which we attribute to the nutrient uptake by forest trees. Therefore both the Mg isotopes and the flux comparison suggest that a substantial part of the major element weathering flux is consumed by the tree biomass. The enrichment of 26Mg over 24Mg in tree trunks relative to leaves suggests that tree trunks account for a substantial fraction of the net uptake of Mg. This isotopic and elemental compartment separation is prevented from obliteration (which would occur by Mg redissolution by two potential effects. Either the mineral nutrients accumulate today in regrowing forest biomass after clear cutting, or they are exported in litter and coarse woody debris (CWD such that they remain in solid biomass. Over pre-forest-management weathering timescales, this removal flux might have been in operation in the form of natural erosion of CWD. Regardless of the removal mechanism, our approach provides entirely novel means towards

Quantifying nutrient uptake as driver of rock weathering in forest ecosystems by magnesium stable isotopes

Science.gov (United States)

Uhlig, David; Schuessler, Jan A.; Bouchez, Julien; Dixon, Jean L.; von Blanckenburg, Friedhelm

2017-06-01

Plants and soil microbiota play an active role in rock weathering and potentially couple weathering at depth with erosion at the soil surface. The nature of this coupling is still unresolved because we lacked means to quantify the passage of chemical elements from rock through higher plants. In a temperate forested landscape characterised by relatively fast (˜ 220 t km-2 yr-1) denudation and a kinetically limited weathering regime of the Southern Sierra Critical Zone Observatory (SSCZO), California, we measured magnesium (Mg) stable isotopes that are sensitive indicators of Mg utilisation by biota. We find that Mg is highly bio-utilised: 50-100 % of the Mg released by chemical weathering is taken up by forest trees. To estimate the tree uptake of other bio-utilised elements (K, Ca, P and Si) we compared the dissolved fluxes of these elements and Mg in rivers with their solubilisation fluxes from rock (rock dissolution flux minus secondary mineral formation flux). We find a deficit in the dissolved fluxes throughout, which we attribute to the nutrient uptake by forest trees. Therefore both the Mg isotopes and the flux comparison suggest that a substantial part of the major element weathering flux is consumed by the tree biomass. The enrichment of 26Mg over 24Mg in tree trunks relative to leaves suggests that tree trunks account for a substantial fraction of the net uptake of Mg. This isotopic and elemental compartment separation is prevented from obliteration (which would occur by Mg redissolution) by two potential effects. Either the mineral nutrients accumulate today in regrowing forest biomass after clear cutting, or they are exported in litter and coarse woody debris (CWD) such that they remain in solid biomass. Over pre-forest-management weathering timescales, this removal flux might have been in operation in the form of natural erosion of CWD. Regardless of the removal mechanism, our approach provides entirely novel means towards the direct quantification of

Assessing changes on poly(ethylene terephthalate) properties after recycling: Mechanical recycling in laboratory versus postconsumer recycled material

Energy Technology Data Exchange (ETDEWEB)

López, María del Mar Castro, E-mail: quimcl02@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); Ares Pernas, Ana Isabel, E-mail: aares@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); Abad López, Ma José, E-mail: mjabad@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); and others

2014-10-15

Keeping rheological, mechanical and thermal properties of virgin poly(ethylene terephthalate), PET, is necessary to assure the quality of second-market applications. A comparative study of these properties has been undertaken in virgin, mechanical recycled and commercial recycled PET samples. Viscoelastic characterization was carried out by rheological measurements. Mechanical properties were estimated by tensile and Charpy impact strength tests. Thermal properties and crystallinity were evaluated by differential scanning calorimetry and a deconvolution procedure was applied to study the population of the different crystals. Molecular conformational changes related to crystallinity values were studied by FTIR spectroscopy. Variations in average molecular weight were predicted from rheology. Besides, the presence-absence of linear and cyclic oligomeric species was measured by mass spectrometry techniques, as MALDI-TOF. Mechanical recycled PET undergoes a significant decline in rheological, mechanical and thermal properties upon increasing the number of reprocessing steps. This is due to the cleavage of the ester bonds with reduction in molar mass and raise in cyclic oligomeric species, in particular [GT{sub c}]{sub n} and [GT{sub c}]{sub n}-G type. Chain shortening plus enrichment in trans conformers favour the crystallization process which occurs earlier and faster with modification in crystal populations. Additional physicochemical steps are necessary to preserve the main benefits of PET. - Highlights: • Combination of multiple techniques to characterize the effects of recycling in PET. • Cleavage of ester bonds reduced viscosity, Mw, toughness in mechanical recycled PET. • Virgin, mechanical recycled and commercial recycled PET differ in crystal populations. • Cyclic oligomers [GT{sub c}]{sub n} and [GT{sub c}]{sub n}-G increase from the fourth extrusion cycle onwards.

Dual recycling for GEO 600

International Nuclear Information System (INIS)

Grote, H; Freise, A; Malec, M; Heinzel, G; Willke, B; Lueck, H; Strain, K A; Hough, J; Danzmann, K

2004-01-01

Dual recycling is the combination of signal recycling and power recycling; both optical techniques improve the shot-noise-limited sensitivity of interferometric gravitational-wave detectors. In addition, signal recycling can reduce the loss of light power due to imperfect interference and allows us, in principle, to beat the standard quantum limit. The interferometric gravitational-wave detector GEO 600 is the first of the kilometre-scale detectors to use signal recycling. We have recently equipped the detector with a signal-recycling mirror with a transmittance of 1%. In this paper, we present details of the detector commissioning and the first locks of the dual-recycled interferometer

Dry Matter Production, Nutrient Cycled and Removed, and Soil Fertility Changes in Yam-Based Cropping Systems with Herbaceous Legumes in the Guinea-Sudan Zone of Benin

Directory of Open Access Journals (Sweden)

Raphiou Maliki

2016-01-01

Full Text Available Traditional yam-based cropping systems (shifting cultivation, slash-and-burn, and short fallow often result in deforestation and soil nutrient depletion. The objective of this study was to determine the impact of yam-based systems with herbaceous legumes on dry matter (DM production (tubers, shoots, nutrients removed and recycled, and the soil fertility changes. We compared smallholders’ traditional systems (1-year fallow of Andropogon gayanus-yam rotation, maize-yam rotation with yam-based systems integrated herbaceous legumes (Aeschynomene histrix/maize intercropping-yam rotation, Mucuna pruriens/maize intercropping-yam rotation. The experiment was conducted during the 2002 and 2004 cropping seasons with 32 farmers, eight in each site. For each of them, a randomized complete block design with four treatments and four replicates was carried out using a partial nested model with five factors: Year, Replicate, Farmer, Site, and Treatment. Analysis of variance (ANOVA using the general linear model (GLM procedure was applied to the dry matter (DM production (tubers, shoots, nutrient contribution to the systems, and soil properties at depths 0–10 and 10–20 cm. DM removed and recycled, total N, P, and K recycled or removed, and soil chemical properties (SOM, N, P, K, and pH water were significantly improved on yam-based systems with legumes in comparison with traditional systems.

Safeguards and nonproliferation aspects of a dry fuel recycling technology

International Nuclear Information System (INIS)

Pillay, K.K.S.

1993-01-01

Los Alamos National Laboratory undertook an independent assessment of the proliferation potentials and safeguardability of a dry fuel recycling technology, whereby spent pressurized-water reactor (PWR) fuels are used to fuel canadian deuterium uranium (CANDU) reactors. Objectives of this study included (1) the evaluation of presently available technologies that may be useful to safeguard technology options for dry fuel recycling (2) and identification of near-term and long-term research needs to develop process-specific safeguards requirements. The primary conclusion of this assessment is that like all other fuel cycle alternatives proposed in the past, the dry fuel recycle entails prolfferation risks and that there are no absolute technical fixes to eliminate such risks. This study further concludes that the proliferation risks of dry fuel recycling options are relatively minimal and presently known safeguards systems and technologies can be modified and/or adapted to meet the requirements of safeguarding such fuel recycle facilities

Performance of Recycled Porous Hot Mix Asphalt with Gilsonite Additive

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Ludfi Djakfar

2015-01-01

Full Text Available The objective of the study is to evaluate the performance of porous asphalt using waste recycled concrete material and explore the effect of adding Gilsonite to the mixture. As many as 90 Marshall specimens were prepared with varied asphalt content, percentage of Gilsonite as an additive, and proportioned recycled and virgin coarse aggregate. The test includes permeability capability and Marshall characteristics. The results showed that recycled concrete materials seem to have a potential use as aggregate in the hot mix asphalt, particularly on porous hot mix asphalt. Adding Gilsonite at ranges 8–10% improves the Marshall characteristic of the mix, particularly its stability, without decreasing significantly the permeability capability of the mix. The use of recycled materials tends to increase the asphalt content of the mix at about 1 to 2% higher. With stability reaching 750 kg, the hot mix recycled porous asphalt may be suitable for use in the local roads with medium vehicle load.

A novel approach to estimating potential maximum heavy metal exposure to ship recycling yard workers in Alang, India

International Nuclear Information System (INIS)

Deshpande, Paritosh C.; Tilwankar, Atit K.; Asolekar, Shyam R.

2012-01-01

The 180 ship recycling yards located on Alang–Sosiya beach in the State of Gujarat on the west coast of India is the world's largest cluster engaged in dismantling. Yearly 350 ships have been dismantled (avg. 10,000 ton steel/ship) with the involvement of about 60,000 workers. Cutting and scrapping of plates or scraping of painted metal surfaces happens to be the commonly performed operation during ship breaking. The pollutants released from a typical plate-cutting operation can potentially either affect workers directly by contaminating the breathing zone (air pollution) or can potentially add pollution load into the intertidal zone and contaminate sediments when pollutants get emitted in the secondary working zone and gets subjected to tidal forces. There was a two-pronged purpose behind the mathematical modeling exercise performed in this study. First, to estimate the zone of influence up to which the effect of plume would extend. Second, to estimate the cumulative maximum concentration of heavy metals that can potentially occur in ambient atmosphere of a given yard. The cumulative maximum heavy metal concentration was predicted by the model to be between 113 μg/Nm 3 and 428 μg/Nm 3 (at 4 m/s and 1 m/s near-ground wind speeds, respectively). For example, centerline concentrations of lead (Pb) in the yard could be placed between 8 and 30 μg/Nm 3 . These estimates are much higher than the Indian National Ambient Air Quality Standards (NAAQS) for Pb (0.5 μg/Nm 3 ). This research has already become the critical science and technology inputs for formulation of policies for eco-friendly dismantling of ships, formulation of ideal procedure and corresponding health, safety, and environment provisions. The insights obtained from this research are also being used in developing appropriate technologies for minimizing exposure to workers and minimizing possibilities of causing heavy metal pollution in the intertidal zone of ship recycling yards in India. -- Highlights

Recycling Potentials of Critical Metals-Analyzing Secondary Flows from Selected Applications

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Till Zimmermann

2014-03-01

Full Text Available Metal mobilization in general, as well as the number of metals used in products to increase performance and provide sometimes unique functionalities, has increased steadily in the past decades. Materials, such as indium, gallium, platinum group metals (PGM, and rare earths (RE, are used ever more frequently in high-tech applications and their criticality as a function of economic importance and supply risks has been highlighted in various studies. Nevertheless, recycling rates are often below one percent. Against this background, secondary flows of critical metals from three different end-of-life products up to 2020 are modeled and losses along the products’ end-of-life (EOL chain are identified. Two established applications of PGM and RE–industrial catalysts and thermal barrier coatings–and CIGS photovoltaic cells as a relatively new product have been analyzed. In addition to a quantification of future EOL flows, the analysis showed that a relatively well working recycling system exists for PGM-bearing catalysts, while a complete loss of critical metals occurs for the other applications. The reasons include a lack of economic incentives, technologically caused material dissipation and other technological challenges.

Potential of Using Recycled Low-Density Polyethylene in Wood Composites Board

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A. C. Igboanugo

2011-03-01

Full Text Available The aim of this study was to investigate the suitability of using recycled low density polyethylene (RLDPE in wood board manufacturing. The composite board was produced by compressive moulding by increasing the percentage LDPE from 30 to 50wt% with interval of 10wt% at a temperatures of 140 and 180oC, pressure of 30-40 Kg/cm2 and pressing time 7-13minutes. The microstructure and mechanical properties: modulus of rupture (MOR, modulus of elasticity (MOE, Tensile strength, impact strength properties of boards were determined. The results showed that high modulus of rupture of 20.31N/mm2and MOE of 1363N/mm2 were obtained from board produced at 140oC, 60/40wt% wood particles/LDPE content. The uniform distribution of the particles and the recycled LDPE in the microstructure of the composites board is the major factor responsible for the improvement in the mechanical properties. The results showed that the MOE, MOR meets the minimum requirements of the European standards, for general purpose. The boards produced had tensile strength that is within the requirement. Hence this LDPE can be used in board production for general purpose applications.

Soil protection strategies in Brandenburg - management of waste recycling on devastated areas subject to recultivation (soil protection in recultivation areas)

International Nuclear Information System (INIS)

Schmidt, M.; Bannick, C.G.

1996-01-01

The article reflects on consideration in the Land (Federal State) Brandenburg in the preliminary stages of a Land regulation on the recycling of wastes on devasted brown coal mining areas from the viewpoint of soil protection. Within the framework of a proposed recultivation, the benefit and harmlessness of recycling shall be examined. The benefits are derived from the preservation, improvement and restoration of soil functions without detrimental effects on other soil functions. In order to make full use of the benefits, a graduated, site-specific system for the main nutrients is presented. For pollutants, different approaches for limitation of the input are discussed. 36 refs., 1 fig., 12 tabs

Effect of hypoxia on benthic nutrient fluxes in the northwestern Black Sea

Science.gov (United States)

Friedrich, J.

2012-04-01

The western Black Sea shelf has been affected by eutrophication from the 1960s to the mid 1990s. A combination of increased nutrient loads from the major inflowing rivers Danube, Dniester and Dnepr and favourable climate conditions led to high productivity regimes. As a consequence, increased oxygen consumption due to decomposition of organic matter caused recurrent seasonal bottom water hypoxia for more than 20 years. In addition, recycling of nutrients from organic matter settling to the seafloor along with tight benthic-pelagic coupling represents an important internal source for productivity, hence internally supporting eutrophication. From the 1970s to 1990s, the benthic and pelagic systems deteriorated and ecosystem structure and functioning changed. Following the collapse of the centrally planned economies in the eastern European countries during the 1990s, the riverine nutrient input decreased, and the ecosystem, now slowly responding, shows signs of recovery; e.g. by a decrease in hypoxic events. In this study, benthic nutrient flux data from in-situ and ex-situ experiments during the 1990s on the Danube-influenced north-western Black Sea shelf and data from the 2000s, including the EU-FP7 HYPOX experiments, are analysed to reveal the effect of hypoxia on benthic nutrient fluxes. Mann-Whitney statistical tests have been applied to demonstrate the significance of differences in fluxes due to varying oxygen conditions in the water. During the 1990s experiments, bottom water hypoxia was encountered in all locations, while during the 2000s hypoxia has been met only during summer in the Danube Prodelta area and near the Dniester mouth. Indeed, bottom water oxygen in the 1990s has been statistically significantly lower than in the 2000s while benthic oxygen consumption was higher during eutrophication-induced hypoxia. The benthic nutrient fluxes in the 1990s and the 2000s however do not differ significantly. During hypoxia, despite ceasing eutrophication

Electron Cloud Measurements in Fermilab Main Injector and Recycler

Energy Technology Data Exchange (ETDEWEB)

Eldred, Jeffrey Scott [Indiana U.; Backfish, M. [Fermilab; Tan, C. Y. [Fermilab; Zwaska, R. [Fermilab

2015-06-01

This conference paper presents a series of electron cloud measurements in the Fermilab Main Injector and Recycler. A new instability was observed in the Recycler in July 2014 that generates a fast transverse excitation in the first high intensity batch to be injected. Microwave measurements of electron cloud in the Recycler show a corresponding depen- dence on the batch injection pattern. These electron cloud measurements are compared to those made with a retard- ing field analyzer (RFA) installed in a field-free region of the Recycler in November. RFAs are also used in the Main Injector to evaluate the performance of beampipe coatings for the mitigation of electron cloud. Contamination from an unexpected vacuum leak revealed a potential vulnerability in the amorphous carbon beampipe coating. The diamond-like carbon coating, in contrast, reduced the electron cloud signal to 1% of that measured in uncoated stainless steel beampipe.

Recycle Alaska: Reduce, Reuse, Recycle. Activities Handbook, Teacher's Guide, and Student Worksheets.

Science.gov (United States)

Alaska State Dept. of Education, Juneau.

Recycling is a very important aspect of conserving the environment for future generations. This guide addresses the topic of litter prevention for the Alaskan environment and contains 42 activities. Activity topics covered include Natural Cycles, Human Interruption of Natural Cycles, Reduce, Reuse, Recycle and Recycled Classroom. Grade level,…

The Diffusion Effect of MSW Recycling

Directory of Open Access Journals (Sweden)

Yi-Tui Chen

2017-12-01

Full Text Available The purpose of this paper is to compare the recycling performance for some waste fractions selected including food waste, bulk waste, paper, metal products, plastics/rubber and glass products and then to develop some directions for the future improvements. The priority of each waste fraction for recycling is also analyzed by using an importance-performance analysis. Traditionally, the recycling rate that is calculated by the ratio of waste recycled to waste collected is used as an indicator to measure recycling performance. Due to a large variation among waste fractions in municipal solid waste (MSW, the recycling rate cannot reflect the actual recycling performance. The ceiling of recycling rate for each waste fraction estimated from the diffusion models is incorporated into a model to calculate recycling performance. The results show that (1 the diffusion effect exists significantly for the recycling of most recyclables but no evidence is found to support the diffusion effect for the recycling of food waste and bulk waste; (2 the recycling performance of waste metal products ranks the top, compared to waste paper, waste glass and other waste fractions; (3 furthermore, an importance-performance analysis (IPA is employed to analyze the priority of recycling programs and thus this paper suggests that the recycling of food waste should be seen as the most priority item to recycle.

Nutrient reduction and climate change cause a potential shift from pelagic to benthic pathways in a eutrophic marine ecosystem

DEFF Research Database (Denmark)

Lindegren, Martin; Blenckner, T.; Stenseth, N.C.

2012-01-01

The degree to which marine ecosystems may support the pelagic or benthic food chain has been shown to vary across natural and anthropogenic gradients for e.g., in temperature and nutrient availability. Moreover, such external forcing may not only affect the flux of organic matter but could trigger...... variables across all trophic levels, we here propose a potential regime shift from pelagic to benthic regulatory pathways; a possible first sign of recovery from eutrophication likely triggered by drastic nutrient reductions (involving both nitrogen and phosphorus), in combination with climate...

Feasibility of recycling lead batteries in GCC region

Energy Technology Data Exchange (ETDEWEB)

Kassem, M.E.

1992-09-01

The dwindling resources of primary lead and growing environmental awareness figure out the recycling of lead as a necessity all over the world. Estimated demands of the Gulf Cooperative Countries Region reveals a lead supply deficiency around 40.000 tonnes per year. Globally, with a stagnation of primary lead production, the spent lead batteries within GCC region provide an excellent potential for a secondary lead industry. This paper deals with the feasibility of recycling lead batteries and highlights its benefits to the region. (orig.).

Tree root systems and nutrient mobilization

DEFF Research Database (Denmark)

Boyle, Jim; Rob, Harrison; Raulund-Rasmussen, Karsten

sometimes stored at depth. Other recent studies on potential release of nutrients due to chemical weathering indicate the importance of root access to deep soil layers. Release profi les clearly indicate depletion in the top layers and a much higher potential in B and C horizons. Review of evaluations......Roots mobilize nutrients via deep penetration and rhizosphere processes inducing weathering of primary minerals. These contribute to C transfer to soils and to tree nutrition. Assessments of these characteristics and processes of root systems are important for understanding long-term supplies...... of nutrient elements essential for forest growth and resilience. Research and techniques have signifi cantly advanced since Olof Tamm’s 1934 base mineral index for Swedish forest soils, and basic nutrient budget estimates for whole-tree harvesting systems of the 1970s. Recent research in areas that include...

Plutonium recycling in PWR

International Nuclear Information System (INIS)

Youinou, G.; Girieud, R.; Guigon, B.

2000-01-01

Two concepts of 100% MOX PWR cores are presented. They are designed such as to minimize the consequences of the introduction of Pu on the core control. The first one has a high moderation ratio and the second one utilizes an enriched uranium support. The important design parameters as well as their capabilities to multi recycle Pu are discussed. We conclude with the potential interest of the two concepts. (author)

Multiply fully recyclable carbon fibre reinforced heat-resistant covalent thermosetting advanced composites.

Science.gov (United States)

Yuan, Yanchao; Sun, Yanxiao; Yan, Shijing; Zhao, Jianqing; Liu, Shumei; Zhang, Mingqiu; Zheng, Xiaoxing; Jia, Lei

2017-03-02

Nondestructive retrieval of expensive carbon fibres (CFs) from CF-reinforced thermosetting advanced composites widely applied in high-tech fields has remained inaccessible as the harsh conditions required to recycle high-performance resin matrices unavoidably damage the structure and properties of CFs. Degradable thermosetting resins with stable covalent structures offer a potential solution to this conflict. Here we design a new synthesis scheme and prepare a recyclable CF-reinforced poly(hexahydrotriazine) resin matrix advanced composite. The multiple recycling experiments and characterization data establish that this composite demonstrates performance comparable to those of its commercial counterparts, and more importantly, it realizes multiple intact recoveries of CFs and near-total recycling of the principal raw materials through gentle depolymerization in certain dilute acid solution. To our best knowledge, this study demonstrates for the first time a feasible and environment-friendly preparation-recycle-regeneration strategy for multiple CF-recycling from CF-reinforced advanced composites.

Opportunities to enhance and interpret nutrient fluxes and imbalances in animal production systems by use of stable isotopes

International Nuclear Information System (INIS)

Jarvis, S.C.

2002-01-01

Full text: The flows and transfers of nutrients within agricultural systems are complex and the presence of livestock increases the complexity. Few, if any, systems are in equilibrium with respect to nutrients inputs and outputs and all are 'leaky' to some extent or other: the presence of animals inevitably increases the opportunity for inefficiency. Whilst there is still much need to enhance nutrient use in many parts of the world in order to promote crop/food production particularly in resource-poor environments, there has been considerable recent research which re- examine nutrient behaviour because of pollution effects. Understanding nutrients fluxes and budgets/balances of inputs and outputs within a system and its component parts, provides the means to assess (i) current status, (ii) extent of losses and (iii) potential options for change to reduce losses, increase nutrient use efficiency and sustain or enhance production at minimum cost. Increasingly, nutrient accounting is being used at field, farm and national scales to aid decision making and planning. To do this effectively, requires that the sources and transfers of nutrients to, from and within the system be known. The paper discusses the way in which systems and farm gate balances can be used to promote efficiency of nutrient use in relation to required production levels and to optimise (i) investment in purchased nutrients, (ii) opportunities to capitalise on internal recycling and (iii) other farming activities which influence nutrient balance, surplus and loss. A major challenge for the future will be to balance the on- and off-farm needs of supplying and utilising nutrients in order to maintain long-term sustainability of farming systems, food production and rural resources. The paper concentrates on aspects of N in livestock systems as this provides one of the main opportunities to increase effectiveness of nutrient use in agriculture throughout the world with the aim of demonstrating some of the

Inspection and control of recycling metals in Iran

International Nuclear Information System (INIS)

Rostampour Samarin, A.

2002-01-01

Full text: Recently, the metal recycling industries have become aware of radioactive materials in metal scrap. There have been some cases where radiation sources were unintentionally smelted in the course of recycling metal scrap internationally. To solve the problem, industry and Regulatory Authority have jointly undertaken initiatives to increase awareness of the problem within the industry. Radiation detection systems have been installed by custom services and mills to lessen the potential for the risk to public health from radiation contamination and for financial losses. Based on above matters, the article presents how National Radiation Protection Department (NRPD) can lessen the imports of potential contamination through several means, such as the installation of monitoring system, and implementation of prevention measures. (author)

Recycling of Organic Wastes to Achieve the Clean Agriculture Approach with Aid of Nuclear Techniques

International Nuclear Information System (INIS)

Moursy, A.A.A.

2012-01-01

The Objective of this current work is to study Organic matter decomposition under clean agriculture system in sandy soil using nuclear technique. This desirtatation has the following targets: - Amendment and improving sandy soil properties - Utilization of farm wastes (Recycling) in safe mode -Benefits form organic matter decomposition. - Follow up the fate of same nutrients (Nitrogen) released in soil media after organic matter (O.M) decomposition and Impact on plant nutrition status.-saving the environment on short and long run.

Compression Molding of Composite of Recycled HDPE and Recycled Tire Particles

Science.gov (United States)

Liu, Ping; Waskom, Tommy L.; Chen, Zhengyu; Li, Yanze; Peng, Linda

1996-01-01

Plastic and rubber recycling is an effective means of reducing solid waste to the environment and preserving natural resources. A project aimed at developing a new composite material from recycled high density polyethylene (HDPE) and recycled rubber is currently being conducted at Eastern Illinois University. The recycled plastic pellets with recycled rubber particles are extruded into some HDPE/rubber composite strands. The strand can be further cut into pellets that can be used to fabricate other material forms or products. This experiment was inspired by the above-mentioned research activity. In order to measure Durometer hardness of the extruded composite, a specimen with relatively large dimensions was needed. Thus, compression molding was used to form a cylindrical specimen of 1 in. diameter and 1 in. thickness. The initial poor quality of the molded specimen prompted a need to optimize the processing parameters such as temperature, holding time, and pressure. Design of experiment (DOE) was used to obtain optimum combination of the parameters.

Material recycling: Presence of chemicals and their influence on the circular economy concept

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Astrup, Thomas Fruergaard

2014-01-01

of the concept is the pursuit of sustainability through re-use and recycling of products and materials once they have served their purpose. Once such materials (e.g. paper, plastics) are recycled, chemicals that they contain are reintroduced,spread or even accumulate in the newly manufactured products (Figure 1...... the recyclability of waste materials with respect to the presence of substances. The outcomes of the work will provide crucial basis for future waste characterization activities, environmental and risk assessments of material recycling, as well as provide authorities, scientific community and society...... with a necessary basis for evaluating potential future limitations to recycling and address means of mitigating accumulation and spreading of chemicals in various materials....

Two novel WD40 domain–containing proteins, Ere1 and Ere2, function in the retromer-mediated endosomal recycling pathway

Science.gov (United States)

Shi, Yufeng; Stefan, Christopher J.; Rue, Sarah M.; Teis, David; Emr, Scott D.

2011-01-01

Regulated secretion, nutrient uptake, and responses to extracellular signals depend on cell-surface proteins that are internalized and recycled back to the plasma membrane. However, the underlying mechanisms that govern membrane protein recycling to the cell surface are not fully known. Using a chemical-genetic screen in yeast, we show that the arginine transporter Can1 is recycled back to the cell surface via two independent pathways mediated by the sorting nexins Snx4/41/42 and the retromer complex, respectively. In addition, we identify two novel WD40-domain endosomal recycling proteins, Ere1 and Ere2, that function in the retromer pathway. Ere1 is required for Can1 recycling via the retromer-mediated pathway, but it is not required for the transport of other retromer cargoes, such as Vps10 and Ftr1. Biochemical studies reveal that Ere1 physically interacts with internalized Can1. Ere2 is present in a complex containing Ere1 on endosomes and functions as a regulator of Ere1. Taken together, our results suggest that Snx4/41/42 and the retromer comprise two independent pathways for the recycling of internalized cell-surface proteins. Moreover, a complex containing the two novel proteins Ere1 and Ere2 mediates cargo-specific recognition by the retromer pathway. PMID:21880895

Certified Electronics Recyclers

Science.gov (United States)

Learn how EPA encourages all electronics recyclers become certified by demonstrating to an accredited, independent third-party auditor and that they meet specific standards to safely recycle and manage electronics.

Produção de serapilheira e ciclagem de nutrientes na cultura do cajueiro anão precoce Litter production and nutrient cycles in the young dwarf cashew culture

Directory of Open Access Journals (Sweden)

Ismail Soares

2008-02-01

decomposição das folhas.This study aimed to (a to evaluate the biomass production from the crown of the young dwarf cashew, clone CCP 76, at 2, 3, 8 and 9 years of culture implantation, (b to determine the rate of leaf decomposition and (c to quantify nutrient contribution potentially available in the biomass to be recycled into the soil. The research was conducted at the Experimental Field of Curu, in Paraipaba - CE, from December, 2003 to January, 2005. The treatments consisted of orchards with trees of 2, 3, 8 and 9 years of plantation, distributed in a completely randomized design with eight replications. Litter was collected using 1 m² collectors with 1 mm² mesh place 40 cm above the soil surface. After sampling, the material was sorted out into portions of leaves, branches, inflorescence, peduncle and nut, oven dried and weighed. In the leaf portion, the compositions of N, P, K, Ca, Mg, S, Na, Cu, Fe, Mn and Zn were determined. Leaves ready to fall were collected from each plant to determine their decomposition rate and 12 g of this material was stove dried, and placed in 20 cm x 20 cm nylon bags and 2 mm mesh which were distributed on the soil surface and collected after 112, 233 and 369 days. In each collection, the material was oven dried and the remaining nutrient biomass (N, P, K, Ca, Mg, S, Na, Cu, Fe, Mn and Zn was determined. The 8- and 9- year- old plants deposited greater quantities of litter during the experimental period and showed greater potential for nutrient recycling. During the experimental period it was generally observed that the decomposition process was fast in the first four months, remaining slow until the end of the observation period. Most of the nutrients in the cashew tree were released in the first four months of leaf composition.

Recycling-friendly planning and construction; Recyclinggerechtes Planen und Bauen

Energy Technology Data Exchange (ETDEWEB)

Willkomm, W. [Hannover Univ. (Germany). Fachbereich Architektur]|[Institut fuer Industrialisierung des Bauens GmbH, Hannover (Germany)

1995-09-01

Building materials recycling is part and parcel of any intelligent, resource-conserving materials recycling concept. Principally, however, it can never be more than the second best solution. This is because it must always come after all has been done to prevent building material residues from arising in the first place. The greatest potential for waste avoidance in the building industry lies in the planning phase. Planning nowadays is oriented more to production, utilisation, reutilisation, maintenance, and recycling processes, i.e. more to processes in general than to the design of any certain product. (orig./HW) [Deutsch] Baustoff-Recycling ist ein unverzichtbarer Beitrag zu intelligenten, resourcensparenden Materialkreislaeufen. Es stellt aber immer nur die zweitbeste Loesung dar. Denn zunaechst muessen alle Moeglichkeiten genutzt werden. Bauabfaelle gar nicht erst entstehen zu lassen. Die groessten Potentiale zur Abfallvermeidung in der Bauproduktion liegen in einer Bauplanung, die sich intensiver als bisher an Herstellungs-, Nutzungs-, Umnutzungs-, Instandhaltungs- und Recyclingprozessen orientiert, also eher prozessorientierte Planung als Produktgestaltung. (orig./HW)

Recycling of radioactively contaminated materials: Public policy issues

International Nuclear Information System (INIS)

Hocking, E.K.

1994-01-01

Recycling radioactively contaminated materials requires varying degrees of interaction among Federal regulatory agencies such as the Nuclear Regulatory Commission (NRC) and the Environmental Protection Agency (EPA), State governments and regulators, the public, and the Department of Energy. The actions of any of these parties can elicit reactions from the other parties and will raise issues that must be addressed in order to achieve a coherent policy on recycling. The paper discusses potential actions and reactions of Federal regulatory agencies (defined as NRC and EPA), the States, and the Department and the policy issues they raise

Effects of shelter and enrichment on the ecology and nutrient cycling of microbial communities of subtidal carbonate sediments.

Science.gov (United States)

Forehead, Hugh I; Kendrick, Gary A; Thompson, Peter A

2012-04-01

The interactions between physical disturbances and biogeochemical cycling are fundamental to ecology. The benthic microbial community controls the major pathway of nutrient recycling in most shallow-water ecosystems. This community is strongly influenced by physical forcing and nutrient inputs. Our study tests the hypotheses that benthic microbial communities respond to shelter and enrichment with (1) increased biomass, (2) change in community composition and (3) increased uptake of inorganic nutrients from the water column. Replicate in situ plots were sheltered from physical disturbance and enriched with inorganic nutrients or left without additional nutrients. At t(0) and after 10 days, sediment-water fluxes of nutrients, O(2) and N(2) , were measured, the community was characterized with biomarkers. Autochthonous benthic microalgal (BMA) biomass increased 30% with shelter and a natural fivefold increase in nutrient concentration; biomass did not increase with greater enrichment. Diatoms remained the dominant taxon of BMA, suggesting that the sediments were not N or Si limited. Bacteria and other heterotrophic organisms increased with enrichment and shelter. Daily exchanges of inorganic nutrients between sediments and the water column did not change in response to shelter or nutrient enrichment. In these sediments, physical disturbance, perhaps in conjunction with nutrient enrichment, was the primary determinant of microbial biomass. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

The effects of recycling loops in food waste management in Japan: based on the environmental and economic evaluation of food recycling.

Science.gov (United States)

Takata, Miki; Fukushima, Kazuyo; Kino-Kimata, Noriko; Nagao, Norio; Niwa, Chiaki; Toda, Tatsuki

2012-08-15

In Japan, a revised Food Recycling Law went into effect in 2007 to promote a "recycling loop" that requires food industries to purchase farm products that are grown using food waste-derived compost/animal feed. To realize and expand food recycling, it is necessary to evaluate how the recycling facilities work in the recycling loop. The purpose of this study is to assess the environmental and economic efficiency of the food recycling facilities that are involved in the recycling loop, which are also known as looped facilities. The global warming potential and running cost of five looped facilities were evaluated by LCA (life cycle assessment) and LCC (life cycle cost) approaches: machine integrated compost, windrow compost, liquid feed, dry feed, and bio-gasification. The LCA results showed low total GHG (greenhouse gas) emissions of -126 and -49 kg-CO(2)/t-waste, respectively, for dry feed and bio-gasification facilities, due to a high substitution effect. The LCC study showed a low running cost for composting facilities of -15,648 and -18,955 yen/t-waste, respectively, due to high revenue from the food waste collection. It was found that the mandatory reporting of food waste emitters to the government increased collection fees; however, the collection fee in animal feed facilities was relatively low because food waste was collected at a low price or nutritious food waste was purchased to produce quality feed. In the characterisation survey of various treatment methods, the composting facilities showed a relatively low environmental impact and a high economic efficiency. Animal feed facilities had a wide distribution of the total GHG emissions, depending on both the energy usage during the drying process and the substitution effect, which were related to the water content of the food waste and the number of recycled products. In comparison with incineration, the majority of the food recycling facilities showed low GHG emissions and economic effectiveness. This

The effects of recycling loops in food waste management in Japan: Based on the environmental and economic evaluation of food recycling

International Nuclear Information System (INIS)

Takata, Miki; Fukushima, Kazuyo; Kino-Kimata, Noriko; Nagao, Norio; Niwa, Chiaki; Toda, Tatsuki

2012-01-01

In Japan, a revised Food Recycling Law went into effect in 2007 to promote a “recycling loop” that requires food industries to purchase farm products that are grown using food waste-derived compost/animal feed. To realize and expand food recycling, it is necessary to evaluate how the recycling facilities work in the recycling loop. The purpose of this study is to assess the environmental and economic efficiency of the food recycling facilities that are involved in the recycling loop, which are also known as looped facilities. The global warming potential and running cost of five looped facilities were evaluated by LCA (life cycle assessment) and LCC (life cycle cost) approaches: machine integrated compost, windrow compost, liquid feed, dry feed, and bio-gasification. The LCA results showed low total GHG (greenhouse gas) emissions of − 126 and − 49 kg-CO 2 /t-waste, respectively, for dry feed and bio-gasification facilities, due to a high substitution effect. The LCC study showed a low running cost for composting facilities of − 15,648 and − 18,955 yen/t-waste, respectively, due to high revenue from the food waste collection. It was found that the mandatory reporting of food waste emitters to the government increased collection fees; however, the collection fee in animal feed facilities was relatively low because food waste was collected at a low price or nutritious food waste was purchased to produce quality feed. In the characterisation survey of various treatment methods, the composting facilities showed a relatively low environmental impact and a high economic efficiency. Animal feed facilities had a wide distribution of the total GHG emissions, depending on both the energy usage during the drying process and the substitution effect, which were related to the water content of the food waste and the number of recycled products. In comparison with incineration, the majority of the food recycling facilities showed low GHG emissions and economic

The effects of recycling loops in food waste management in Japan: Based on the environmental and economic evaluation of food recycling

Energy Technology Data Exchange (ETDEWEB)

Takata, Miki [Graduate School of Engineering, Soka University, Hachioji, Tokyo 192-8577 (Japan); Fukushima, Kazuyo [Watanabe Oyster Laboratory Co., Ltd, Hachioji, Tokyo 192-0154 (Japan); Kino-Kimata, Noriko [Graduate School of Engineering, Soka University, Hachioji, Tokyo 192-8577 (Japan); Nagao, Norio [Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Niwa, Chiaki [Graduate School of Engineering, Soka University, Hachioji, Tokyo 192-8577 (Japan); Toda, Tatsuki, E-mail: toda@soka.ac.jp [Graduate School of Engineering, Soka University, Hachioji, Tokyo 192-8577 (Japan)

2012-08-15

In Japan, a revised Food Recycling Law went into effect in 2007 to promote a 'recycling loop' that requires food industries to purchase farm products that are grown using food waste-derived compost/animal feed. To realize and expand food recycling, it is necessary to evaluate how the recycling facilities work in the recycling loop. The purpose of this study is to assess the environmental and economic efficiency of the food recycling facilities that are involved in the recycling loop, which are also known as looped facilities. The global warming potential and running cost of five looped facilities were evaluated by LCA (life cycle assessment) and LCC (life cycle cost) approaches: machine integrated compost, windrow compost, liquid feed, dry feed, and bio-gasification. The LCA results showed low total GHG (greenhouse gas) emissions of - 126 and - 49 kg-CO{sub 2}/t-waste, respectively, for dry feed and bio-gasification facilities, due to a high substitution effect. The LCC study showed a low running cost for composting facilities of - 15,648 and - 18,955 yen/t-waste, respectively, due to high revenue from the food waste collection. It was found that the mandatory reporting of food waste emitters to the government increased collection fees; however, the collection fee in animal feed facilities was relatively low because food waste was collected at a low price or nutritious food waste was purchased to produce quality feed. In the characterisation survey of various treatment methods, the composting facilities showed a relatively low environmental impact and a high economic efficiency. Animal feed facilities had a wide distribution of the total GHG emissions, depending on both the energy usage during the drying process and the substitution effect, which were related to the water content of the food waste and the number of recycled products. In comparison with incineration, the majority of the food recycling facilities showed low GHG emissions and economic

Regional hydrocarbon contaminated soil recycling facility standards

International Nuclear Information System (INIS)

Warren, R.

1992-01-01

In an effort to protect the environment from uncontrolled releases of petroleum products, the Canadian Petroleum Products Institute member companies have initiated environmental upgrading programs for their underground fuel storage systems in British Columbia. These programs have been restricted in recent years as a result of environmental regulations targeting contaminated soil, which is generated when underground storage tanks are upgraded to current standards. The soil requiring treatment is typically sand backfill containing a nominal value of petroleum product. These soils can be treated in an engineered basin using bioremediation technology to reduce the level of contamination. Depending on the degree of treatment, the soil can be recycled as backfill or reused as landfill cover. An overview is presented of the basin treatment process and design. Natural bioremediation is enhanced with nutrients, water and oxygen addition. 4 figs

Treatment of biofuel ashes for forest recycling; Behandling av aska fraan biobraenslen foer spridning paa skogsmark - etapp 1

Energy Technology Data Exchange (ETDEWEB)

Bjurstroem, H.; Sjoeblom, R. [AaF-Energikonsult, Stockholm (Sweden)

1997-03-01

Logging residues are the easiest available fuel for an increased production of energy in Sweden from renewable sources. A consequence of their removal from the forest is that the cycle of mineral nutrients is broken. The purpose of recycling the ash after this fuel to forest land is to compensate for the removal and close again the nutrient cycle. Recycling nutrients and returning the inorganic components of the biomass removed from the forest should be performed in accordance with general principles of environmental protection, health considerations and the good house-keeping of natural resources. The activities should also be carried out in accordance with the needs of the forest and energy plant owners regarding good technology and economy. This implies that functional requirements originating from these principles and needs should be clearly structured and formulated and that such requirements should provide a basis for the continued development work as well as for the implementation of suitable, economical and efficient systems. Returning inorganic constituents implies that the principle of recirculation is followed as well as that nutrients are brought back which improves accretion in the forest. At the same time, the risk of damage to the forest can be assessed as insignificant. Furthermore the risks to human health are also assessed to be insignificant provided that pertinent precautions are taken to avoid dusting. In the present report, technical and economical aspects of importance for the selection of method as well as for the establishment of a system are described and discussed. The need for further development work is identified in the following areas: functional requirements - operational requirements, sampling, testing and quality assurance, granulation, curing processes and drying/sintering. 102 refs, 1 fig, 2 tabs

PET and Recycling

Directory of Open Access Journals (Sweden)

Funda Sevencan

2007-08-01

Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull. 2007; 6(4: 307-312

PET and Recycling

Directory of Open Access Journals (Sweden)

Funda Sevencan

2007-08-01

Full Text Available This review aims to clarify the need of decreasing the environmental effects caused by human and draw attention to the increasing environmental effects of plastics wastes. Plastics consist of organic molecules with high density molecules or polymers. Main resources of plastics are the residue of oil rafineries. Several advantages of plastics, have increased the usage continuously. Polyethylene Terephthalate (PET is the most commonly used plastics. PET is used to protect food, drinking water, fruit juice, alcoholic beverage, and food packing films. By the increasing interest on the environmental effects of plastic wastes, concerns on the recyclable packing materials also grew up. Also the daily use of recyclable containers consisting PET have increased. There are five steps for recycling of plastics. These steps are; using large amounts of plastics, collecting them in a big center, classifying and sorting the plastics, reproducing the polymers and obtaining new products with melted plastics. Providing a healthy recycling of plastics, the consumers should have knowledge and responsibility. The consumer should know what he/she has to do before putting the plastics in the recycling containers. Recycling containers and bags should be placed near the sources of plastic wastes. Consequently, the plastic wastes and environmental problems they cause will be on the agenda in future. [TAF Prev Med Bull 2007; 6(4.000: 307-312

Waste printed circuit board recycling techniques and product utilization

International Nuclear Information System (INIS)

Hadi, Pejman; Xu, Meng; Lin, Carol S.K.; Hui, Chi-Wai; McKay, Gordon

2015-01-01

Highlights: • There is a major environmental issue about the printed circuit boards throughout the world. • Different physical and chemical recycling techniques have been reviewed. • Nonmetallic fraction of PCBs is the unwanted face of this waste stream. • Several applications of the nonmetallic fraction of waste PCBs have been introduced. - Abstract: E-waste, in particular waste PCBs, represents a rapidly growing disposal problem worldwide. The vast diversity of highly toxic materials for landfill disposal and the potential of heavy metal vapors and brominated dioxin emissions in the case of incineration render these two waste management technologies inappropriate. Also, the shipment of these toxic wastes to certain areas of the world for eco-unfriendly “recycling” has recently generated a major public outcry. Consequently, waste PCB recycling should be adopted by the environmental communities as an ultimate goal. This article reviews the recent trends and developments in PCB waste recycling techniques, including both physical and chemical recycling. It is concluded that the physical recycling techniques, which efficiently separate the metallic and nonmetallic fractions of waste PCBs, offer the most promising gateways for the environmentally-benign recycling of this waste. Moreover, although the reclaimed metallic fraction has gained more attention due to its high value, the application of the nonmetallic fraction has been neglected in most cases. Hence, several proposed applications of this fraction have been comprehensively examined

Waste printed circuit board recycling techniques and product utilization

Energy Technology Data Exchange (ETDEWEB)

Hadi, Pejman; Xu, Meng [Chemical and Biomolecular Engineering Department, Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong Special Administrative Region (Hong Kong); Lin, Carol S.K. [School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region (Hong Kong); Hui, Chi-Wai [Chemical and Biomolecular Engineering Department, Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong Special Administrative Region (Hong Kong); McKay, Gordon, E-mail: kemckayg@ust.hk [Chemical and Biomolecular Engineering Department, Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong Special Administrative Region (Hong Kong); Division of Sustainable Development, College of Science, Engineering and Technology, Hamad Bin Khalifa University, Qatar Foundation, Doha (Qatar)

2015-02-11

Highlights: • There is a major environmental issue about the printed circuit boards throughout the world. • Different physical and chemical recycling techniques have been reviewed. • Nonmetallic fraction of PCBs is the unwanted face of this waste stream. • Several applications of the nonmetallic fraction of waste PCBs have been introduced. - Abstract: E-waste, in particular waste PCBs, represents a rapidly growing disposal problem worldwide. The vast diversity of highly toxic materials for landfill disposal and the potential of heavy metal vapors and brominated dioxin emissions in the case of incineration render these two waste management technologies inappropriate. Also, the shipment of these toxic wastes to certain areas of the world for eco-unfriendly “recycling” has recently generated a major public outcry. Consequently, waste PCB recycling should be adopted by the environmental communities as an ultimate goal. This article reviews the recent trends and developments in PCB waste recycling techniques, including both physical and chemical recycling. It is concluded that the physical recycling techniques, which efficiently separate the metallic and nonmetallic fractions of waste PCBs, offer the most promising gateways for the environmentally-benign recycling of this waste. Moreover, although the reclaimed metallic fraction has gained more attention due to its high value, the application of the nonmetallic fraction has been neglected in most cases. Hence, several proposed applications of this fraction have been comprehensively examined.

Reusing and recycling in Saskatchewan: Environmental benefits of reusing and recycling

Energy Technology Data Exchange (ETDEWEB)

1994-01-01

After an introduction explaining the environmental benefits of reusing and recycling, as well as providing suggestions on minimizing waste and conserving energy, a directory of recyclers and handlers of various kinds of waste in Saskatchewan is presented. Names, addresses/telephone numbers, and types of materials accepted are given for recyclers of animal products, clothing or textiles, glass, compostable materials, industrial hardware, metals, office products, paper, plastic, and tires. Collection depots in the SARCAN recycling program for beverage containers are listed, giving town name, address, hours of operation, and telephone number. Receivers of waste dangerous goods are listed under the categories of ozone-depleting substances, waste batteries, solvents, lubricating oils and oil filters, paint, flammable liquids, antifreeze, drycleaning waste, and miscellaneous.

Recycling of Paper and Cardboard

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Damgaard, Anders

2011-01-01

waste. Recycling of paper and cardboard production waste and postconsumer waste has a long history in the pulp and paper industry. The recycled material now makes up more than half of the raw material used in European pulp and paper industry (ERPC, 2004). This chapter describes briefly how paper...... and cardboard are produced and how waste paper is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of paper recycling....

Water Recycling in Australia

Directory of Open Access Journals (Sweden)

Ross Young

2011-09-01

Full Text Available Australia is the driest inhabited continent on earth and, more importantly, experiences the most variable rainfall of all the continents on our planet. The vast majority of Australians live in large cities on the coast. Because wastewater treatments plants were all located near the coast, it was thought that large scale recycling would be problematic given the cost of infrastructure and pumping required to establish recycled water schemes. This all changed when Australia experienced a decade of record low rainfall and water utilities were given aggressive targets to increase the volume of water recycled. This resulted in recycled water being accepted as a legitimate source of water for non-drinking purposes in a diversified portfolio of water sources to mitigate climate risk. To ensure community support for recycled water, Australia lead the world in developing national guidelines for the various uses of recycled water to ensure the protection of public health and the environment. Australia now provides a great case study of the developments in maximizing water recycling opportunities from policy, regulatory and technological perspectives. This paper explores the evolution in thinking and how approaches to wastewater reuse has changed over the past 40 years from an effluent disposal issue to one of recognizing wastewater as a legitimate and valuable resource. Despite recycled water being a popular choice and being broadly embraced, the concept of indirect potable reuse schemes have lacked community and political support across Australia to date.

Aluminium beverage can recycling

Energy Technology Data Exchange (ETDEWEB)

Lewinski, A von

1985-08-01

Canned beverages have become a controversial issue in this era of ecological sensitivity. METALL has already discussed the problem of can recycling. The present article discusses the technical aspects of aluminium can recycling. Two further articles will follow on aluminium can recycling in North America and on the results of European pilot projects.

Topics under debate - Should uniform release criteria be established for metal recycling?

International Nuclear Information System (INIS)

Kennedy K.E. Jr., LaMastra, A.; McDonald, J.C.

2001-01-01

Many nuclear facilities have large quantities of metals that have potential value, but are slightly radioactive. These metals include copper, aluminium and steel that could be recycled and used in applications for which a small amount of radioactivity is not important. Perhaps it is possible to define the conditions under which these metals could be safely recycled. However, it is not clear that recycling of such metals would be considered to be useful by the metals industries, for a variety of reasons. In this debate, the merits and risks associated with recycling are discussed. Our participants are quite familiar with this question, and they have presented their views in the arguments and rebuttals that follow. (author)

Fatal chlorine gas exposure at a metal recycling facility: Case report.

Science.gov (United States)

Harvey, Robert R; Boylstein, Randy; McCullough, Joel; Shumate, Alice; Yeoman, Kristin; Bailey, Rachel L; Cummings, Kristin J

2018-06-01

At least four workers at a metal recycling facility were hospitalized and one died after exposure to chlorine gas when it was accidentally released from an intact, closed-valved cylinder being processed for scrap metal. This unintentional chlorine gas release marks at least the third such incident at a metal recycling facility in the United States since 2010. We describe the fatal case of the worker whose clinical course was consistent with acute respiratory distress syndrome (ARDS) following exposure to high concentrations of chlorine gas. This case report emphasizes the potential risk of chlorine gas exposure to metal recycling workers by accepting and processing intact, closed-valved containers. The metal recycling industry should take steps to increase awareness of this established risk to prevent future chlorine gas releases. Additionally, public health practitioners and clinicians should be aware that metal recycling workers are at risk for chlorine gas exposure. © 2018 Wiley Periodicals, Inc.

Recent advances in modeling nutrient utilization in ruminants.

Science.gov (United States)

Kebreab, E; Dijkstra, J; Bannink, A; France, J

2009-04-01

Mathematical modeling techniques have been applied to study various aspects of the ruminant, such as rumen function, postabsorptive metabolism, and product composition. This review focuses on advances made in modeling rumen fermentation and its associated rumen disorders, and energy and nutrient utilization and excretion with respect to environmental issues. Accurate prediction of fermentation stoichiometry has an impact on estimating the type of energy-yielding substrate available to the animal, and the ratio of lipogenic to glucogenic VFA is an important determinant of methanogenesis. Recent advances in modeling VFA stoichiometry offer ways for dietary manipulation to shift the fermentation in favor of glucogenic VFA. Increasing energy to the animal by supplementing with starch can lead to health problems such as subacute rumen acidosis caused by rumen pH depression. Mathematical models have been developed to describe changes in rumen pH and rumen fermentation. Models that relate rumen temperature to rumen pH have also been developed and have the potential to aid in the diagnosis of subacute rumen acidosis. The effect of pH has been studied mechanistically, and in such models, fractional passage rate has a large impact on substrate degradation and microbial efficiency in the rumen and should be an important theme in future studies. The efficiency with which energy is utilized by ruminants has been updated in recent studies. Mechanistic models of N utilization indicate that reducing dietary protein concentration, matching protein degradability to the microbial requirement, and increasing the energy status of the animal will reduce the output of N as waste. Recent mechanistic P models calculate the P requirement by taking into account P recycled through saliva and endogenous losses. Mechanistic P models suggest reducing current P amounts for lactating dairy cattle to at least 0.35% P in the diet, with a potential reduction of up to 1.3 kt/yr. A model that

The Fernald Waste Recycling Program

International Nuclear Information System (INIS)

Motl, G.P.

1993-01-01

Recycling is considered a critical component of the waste disposition strategy at the Fernald Plant. It is estimated that 33 million cubic feet of waste will be generated during the Fernald cleanup. Recycling some portion of this waste will not only conserve natural resources and disposal volume but will, even more significantly, support the preservation of existing disposition options such as off-site disposal or on-site storage. Recognizing the strategic implications of recycling, this paper outlines the criteria used at Fernald to make recycle decisions and highlights several of Fernald's current recycling initiatives

Assessment of forest nutrient pools in view of biomass potentials - a case study from Austria oak stands

Science.gov (United States)

Yan, S.; Bruckman, V. J.; Glatzel, G.; Hochbichler, E.

2012-04-01

As one of the renewable energy forms, bio-energy could help to relieve the pressure which is caused by growing global energy demand. In Austria, large area of forests, traditional utilization of biomass and people's desire to live in a sound environment have supported the positive development of bio-energy. Soil nutrient status is in principle linked with the productivity of the aboveground biomass. This study focuses on K, Ca and Mg pools in soils and aboveground biomass in order to learn more on the temporal dynamics of plant nutrients as indicators for biomass potentials in Quercus dominated forests in northeastern Austria. Three soil types (according to WRB: eutric cambisol, calcic chernozem and haplic luvisol) were considered representative for the area and sampled. We selected nine Quercus petraea dominated permanent plots for this study. Exchangeable cations K, Ca and Mg in the soils were quantified in our study plots. Macronutrients pools of K, Ca and Mg in aboveground biomass were calculated according to inventory data and literature review. The exchangeable cations pool in the top 50 cm of the soil were 882 - 1,652 kg ha-1 for K, 2,661 to 16,510 kg ha-1 for Ca and 320 - 1,850 kg ha-1 for Mg. The nutrient pool in aboveground biomass ranged from 29 to 181 kg ha-1 for K, from 56 to 426 kg ha-1 for Ca and from 4 to 26 kg ha-1 for Mg. The underground exchangeable pools of K, Ca and Mg are generally 10, 22 and 58 times higher than aboveground biomass nutrient pools. Our results showed that the nutrient pools in the mineral soil are sufficient to support the tree growth. The levels of soil nutrients in particular K, Ca and Mg in our study areas are reasonably high and do not indicate the necessity for additional fertilization under current silvicultural practices and biomass extraction rate. The forest in our study areas is in favorable condition to supply biomass as raw material for energy utilization.

A novel approach to estimating potential maximum heavy metal exposure to ship recycling yard workers in Alang, India

Energy Technology Data Exchange (ETDEWEB)

Deshpande, Paritosh C.; Tilwankar, Atit K.; Asolekar, Shyam R., E-mail: asolekar@iitb.ac.in

2012-11-01

The 180 ship recycling yards located on Alang-Sosiya beach in the State of Gujarat on the west coast of India is the world's largest cluster engaged in dismantling. Yearly 350 ships have been dismantled (avg. 10,000 ton steel/ship) with the involvement of about 60,000 workers. Cutting and scrapping of plates or scraping of painted metal surfaces happens to be the commonly performed operation during ship breaking. The pollutants released from a typical plate-cutting operation can potentially either affect workers directly by contaminating the breathing zone (air pollution) or can potentially add pollution load into the intertidal zone and contaminate sediments when pollutants get emitted in the secondary working zone and gets subjected to tidal forces. There was a two-pronged purpose behind the mathematical modeling exercise performed in this study. First, to estimate the zone of influence up to which the effect of plume would extend. Second, to estimate the cumulative maximum concentration of heavy metals that can potentially occur in ambient atmosphere of a given yard. The cumulative maximum heavy metal concentration was predicted by the model to be between 113 {mu}g/Nm{sup 3} and 428 {mu}g/Nm{sup 3} (at 4 m/s and 1 m/s near-ground wind speeds, respectively). For example, centerline concentrations of lead (Pb) in the yard could be placed between 8 and 30 {mu}g/Nm{sup 3}. These estimates are much higher than the Indian National Ambient Air Quality Standards (NAAQS) for Pb (0.5 {mu}g/Nm{sup 3}). This research has already become the critical science and technology inputs for formulation of policies for eco-friendly dismantling of ships, formulation of ideal procedure and corresponding health, safety, and environment provisions. The insights obtained from this research are also being used in developing appropriate technologies for minimizing exposure to workers and minimizing possibilities of causing heavy metal pollution in the intertidal zone of ship recycling

The recycling is moving

CERN Multimedia

GS Department

2011-01-01

The recycling site currently situated near building 133 has been transferred to the car park of building 156. The site is identified by the sign “RECYCLING” and the above logo. In this new, more accessible site, you will find recycling bins for the following waste: PET (recyclable plastic bottles); Aluminium cans; Nespresso coffee capsules.  

Environmental Aspects of Use of Recycled Carbon Fiber Composites in Automotive Applications.

Science.gov (United States)

Meng, Fanran; McKechnie, Jon; Turner, Thomas; Wong, Kok H; Pickering, Stephen J

2017-11-07

The high cost and energy intensity of virgin carbon fiber manufacture provides an opportunity to recover substantial value from carbon fiber reinforced plastic wastes. In this study, we assess the life cycle environmental implications of recovering carbon fiber and producing composite materials as substitutes for conventional and proposed lightweight materials in automotive applications (e.g., steel, aluminum, virgin carbon fiber). Key parameters for the recycled carbon fiber materials, including fiber volume fraction and fiber alignment, are investigated to identify beneficial uses of recycled carbon fiber in the automotive sector. Recycled carbon fiber components can achieve the lowest life cycle environmental impacts of all materials considered, although the actual impact is highly dependent on the design criteria (λ value) of the specific component. Low production impacts associated with recycled carbon fiber components are observed relative to lightweight competitor materials (e.g., aluminum, virgin carbon fiber reinforced plastic). In addition, recycled carbon fiber components have low in-use energy use due to mass reductions and associated reduction in mass-induced fuel consumption. The results demonstrate environmental feasibility of the CFRP recycling materials, supporting the emerging commercialization of CF recycling technologies and identifying significant potential market opportunities in the automotive sector.

The potential contribution of yellow cassava to dietary nutrient adequacy of primary-school children in Eastern Kenya; the use of linear programming

OpenAIRE

Talsma, Elise F.; Borgonjen-van den Berg, Karin J.; Melse-Boonstra, Alida; Mayer, Eva V.; Verhoef, Hans; Demir, Ayşe Y.; Ferguson, Elaine L.; Kok, Frans J.; Brouwer, Inge D.

2018-01-01

Objective: Introduction of biofortified cassava as school lunch can increase vitamin A intake, but may increase risk of other deficiencies due to poor nutrient profile of cassava. We assessed the potential effect of introducing a yellow cassava-based school lunch combined with additional food-based recommendations (FBR) on vitamin A and overall nutrient adequacy using Optifood (linear programming tool). Design: Cross-sectional study to assess dietary intakes (24 h recall) and derive model par...

Direction of CRT waste glass processing: electronics recycling industry communication.

Science.gov (United States)

Mueller, Julia R; Boehm, Michael W; Drummond, Charles

2012-08-01

Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, and the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tire Recycling

Science.gov (United States)

1997-01-01

Cryopolymers, Inc. tapped NASA expertise to improve a process for recycling vehicle tires by converting shredded rubber into products that can be used in asphalt road beds, new tires, hoses, and other products. In conjunction with the Southern Technology Applications Center and Stennis Space Center, NASA expertise in cryogenic fuel-handling needed for launch vehicle and spacecraft operations was called upon to improve the recycling concept. Stennis advised Cryopolymers on the type of equipment required, as well as steps to reduce the amount of liquid nitrogen used in the process. They also guided the company to use more efficient ways to control system hardware. It is estimated that more than 300 million tires nationwide are produced per year. Cryopolymers expects to reach a production rate of 5,000 tires recycled per day.

Uranium oxide recycling to give more sustainable power generation

International Nuclear Information System (INIS)

Hagger, R.; Garner, D.S.J.; Beaumont, D.M.; Hesketh, K.

2001-01-01

In broad terms there are two routes for irradiated nuclear fuel, the closed cycle involving recycling and the open cycle culminating in direct disposal. The benefits of following the closed cycle are presented. The environmental burdens associated with open and closed cycles are compared using Life Cycle Assessment (LCA) for non-active burdens and human irradiation. Consideration is given to the extension of the nuclear fuel cycle to include a proportion of MOX fuel elements within a reactor core, and the impact in terms of total activity, waste volumes and Integrated Toxic Potential (ITP) discussed. The potential of moving to a fast reactor cycle is also raised in support of the recycling of spent nuclear fuel giving sustainable power generation. (author)

Investigations on Fresh and Hardened Properties of Recycled Aggregate Self Compacting Concrete

Science.gov (United States)

Revathi, P.; Selvi, R. S.; Velin, S. S.

2013-09-01

In the recent years, construction and demolition waste management issues have attracted the attention from researchers around the world. In the present study, the potential usage of recycled aggregate obtained from crushed demolition waste for making self compacting concrete (SCC) was researched. The barriers in promoting the use of recycled material in new construction are also discussed. In addition, the results of an experimental study involving the use of recycled concrete aggregate as coarse aggregates for producing self-compacting concrete to study their flow and strength characteristics are also presented. Five series of mixture were prepared with 0, 25, 50, 75, and 100 % coarse recycled aggregate adopting Nan Su's mix proportioning method. The fresh concrete properties were evaluated through the slump flow, J-ring and V-funnel tests. Compressive and tensile strengths were also determined. The results obtained showed that SCC could be successfully developed by incorporating recycled aggregates.

Waste reduction and recycling initiatives in Japanese cities: lessons from Yokohama and Kamakura.

Science.gov (United States)

Hotta, Yasuhiko; Aoki-Suzuki, Chika

2014-09-01

Waste reduction and recycling at the city level will acquire greater significance in the near future due to rising global volumes of waste. This paper seeks to identify policy-relevant drivers for successful promotion of waste reduction and recycling. Factors influencing the success of waste reduction and recycling campaigns are identified. Two case study cities in Japan which depict the successful use of the 3Rs (reduce, reuse and recycle) at the municipal level are presented. In these cases, the existence of incinerators, which are generally considered as disincentives for recycling, was not functioning as a disincentive but rather as an incentive for waste reduction. Owing to the high cost of incineration facilities, the movement to close incinerators has become a strong incentive for waste reduction and recycling in these two cities. The study suggests that careful consideration is necessary when making decisions concerning high-cost waste treatment facilities with high installation, maintenance and renewal outlays. In addition, intensive source separation and other municipal recycling initiatives have a high potential for producing positive results. © The Author(s) 2014.

Recycle Glass in Foam Glass Production

DEFF Research Database (Denmark)

Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

The foam glass industry turn recycle glass into heat insulating building materials. The foaming process is relative insensitive to impurities in the recycle glass. It is therefore considered to play an important role in future glass recycling. We show and discuss trends of use of recycled glasses...... in foam glass industry and the supply sources and capacity of recycle glass....

Direction of CRT waste glass processing: Electronics recycling industry communication

International Nuclear Information System (INIS)

Mueller, Julia R.; Boehm, Michael W.; Drummond, Charles

2012-01-01

Highlights: ► Given a large flow rate of CRT glass ∼10% of the panel glass stream will be leaded. ► The supply of CRT waste glass exceeded demand in 2009. ► Recyclers should use UV-light to detect lead oxide during the separation process. ► Recycling market analysis techniques and results are given for CRT glass. ► Academic initiatives and the necessary expansion of novel product markets are discussed. - Abstract: Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, and the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased.

Recycling of Metals

DEFF Research Database (Denmark)

Damgaard, Anders; Christensen, Thomas Højlund

2011-01-01

Metals like iron and aluminium are produced from mineral ore and used for a range of products, some of which have very short lifetimes and thus constitute a major fraction of municipal waste. Packaging in terms of cans, foils and containers are products with a short lifetime. Other products like...... appliances, vehicles and buildings, containing iron and aluminium metals, have long lifetimes before they end up in the waste stream. The recycling of production waste and postconsumer metals has a long history in the metal industry. Some metal smelters are today entirely based on scarp metals. This chapter...... describes briefly how iron and aluminium are produced and how scrap metal is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of metal recycling. Copper and other metals are also found in waste but in much smaller...

Nuclear reactor recyclation device

International Nuclear Information System (INIS)

Takigawa, Yukio; Chuma, Kazuto

1987-01-01

Purpose: To prevent the unevenness for the coolant flow rate even when abnormality occurs to one of recycling pumps. Constitution: A plurality of jet pumps disposed at an interval around the reactor core are divided circumferentially into two sets, and a pipeway is disposed to the outside of each pair including recycling pumps corresponding to each of the sets. The pipeway is connected to the recycling inlet of the jet pump by way of a manifold. The discharge portion of the recycling pumps of the loop pipeway are connected with each other by way of communication pipes, and a normally closed valve is disposed to the communication pipe and the normally closed valve of the communication pipe is opened upon detecting abnormality for one of the recycling pumps. Thus, if either one of the pair of recycling pumps shows abnormal state, coolants flows from the other of pipeway to the outside of the loop pipeway and coolants are supplied from all the jet pumps to the reactor core portion and, accordingly, the not-uniform flow rate can be prevented to eliminate undesired effect on the reactor core. (Kamimura, M.)

Recycling - Danish Waste Management Strategy

DEFF Research Database (Denmark)

Romann, Anne Funch; Thøgersen, John; Husmer, Lis

The report challanges recycling as the only waste handling strategy. The tonnes of recycled materials should not be the only goal - it is essential to minimize the waste production and focus on eliminating hazardous materials.......The report challanges recycling as the only waste handling strategy. The tonnes of recycled materials should not be the only goal - it is essential to minimize the waste production and focus on eliminating hazardous materials....

Length sensing and control of a Michelson interferometer with power recycling and twin signal recycling cavities.

Science.gov (United States)

Gräf, Christian; Thüring, André; Vahlbruch, Henning; Danzmann, Karsten; Schnabel, Roman

2013-03-11

The techniques of power recycling and signal recycling have proven as key concepts to increase the sensitivity of large-scale gravitational wave detectors by independent resonant enhancement of light power and signal sidebands within the interferometer. Developing the latter concept further, twin signal recycling was proposed as an alternative to conventional detuned signal recycling. Twin signal recycling features the narrow-band sensitivity gain of conventional detuned signal recycling but furthermore facilitates the injection of squeezed states of light, increases the detector sensitivity over a wide frequency band and requires a less complex detection scheme for optimal signal readout. These benefits come at the expense of an additional recycling mirror, thus increasing the number of degrees of freedom in the interferometer which need to be controlled.In this article we describe the development of a length sensing and control scheme and its successful application to a tabletop-scale power recycled Michelson interferometer with twin signal recycling. We were able to lock the interferometer in all relevant longitudinal degrees of freedom and thus laid the foundation for further investigations of this interferometer configuration to evaluate its viability for the application in gravitational wave detectors.

Potential for reuse of effluent from fish-processing industries

Directory of Open Access Journals (Sweden)

Luana Morena Rodrigues Vitor Dias Ferraciolli

2017-09-01

Full Text Available The most common problems in the fish processing industry relate to high water consumption and the generation of effluents with concentrated organic loads. Given that reuse can represent an alternative for sustainable development, this study sought to assess the potential for recycling effluents produced in a fish-processing plant. In order to do so, the final industrial effluent was analyzed using the American Public Health Association (APHA standard effluent-analysis method (2005. In addition, the study assessed treatments which produce effluents meeting the requirements prescribed by different countries' regulations for reuse and recycling. The results found that effluents with smaller organic loads, such as those from health barriers and monoblock washing, can be treated in order to remove nutrients and solids so that they can be subsequently reused. For effluents produced by the washing and gutting cylinders, it is recommended that large fragments of solid waste be removed beforehand. Effluents can in this way attain a quality compatible with industrial reuse. This study further highlights the possibility of treating effluents so as comply with drinking water standards. This would potentially allow them to be used within the actual fish-processing procedure; in such a case, a revision of standards and measures for controlling use should be considered to prevent microbiological damage to products and risks to handlers and final consumers.

Nuclear recycling: costs, savings, and safeguards

International Nuclear Information System (INIS)

Spinrad, B.I.

1985-01-01

This chapter discusses the economics, physical and chemical processes, and safety of nuclear fuel recycling. The spent fuel must be chemically reprocessed in order to recover uranium and plutonium. Topics considered include indifference costs, recycling in light water reactors (LWRs), plutonium in fast reactors, the choice between recycling and storage, safeguards, and weapons proliferation. It is shown that the economics of recycling nuclear fuel involves the actual costs and savings of the recycling operation in terms of money spent, made, and saved, and the impact of the recycling on the future cost of uranium

The potential of freshwater macroalgae as a biofuels feedstock and the influence of nutrient availability on freshwater macroalgal biomass production

Science.gov (United States)

Yun, Jin-Ho

Extensive efforts have been made to evaluate the potential of microalgae as a biofuel feedstock during the past 4-5 decades. However, filamentous freshwater macroalgae have numerous characteristics that favor their potential use as an alternative algal feedstock for biofuels production. Freshwater macroalgae exhibit high rates of areal productivity, and their tendency to form dense floating mats on the water surface imply significant reductions in harvesting and dewater costs compared to microalgae. In Chapter 1, I reviewed the published literature on the elemental composition and energy content of five genera of freshwater macroalgae. This review suggested that freshwater macroalgae compare favorably with traditional bio-based energy sources, including terrestrial residues, wood, and coal. In addition, I performed a semi-continuous culture experiment using the common Chlorophyte genus Oedogonium to investigate whether nutrient availability can influence its higher heating value (HHV), productivity, and proximate analysis. The experimental study suggested that the most nutrient-limited growth conditions resulted in a significant increase in the HHV of the Oedogonium biomass (14.4 MJ/kg to 16.1 MJ/kg). Although there was no significant difference in productivity between the treatments, the average dry weight productivity of Oedogonium (3.37 g/m2/day) was found to be much higher than is achievable with common terrestrial plant crops. Although filamentous freshwater macroalgae, therefore, have significant potential as a renewable source of bioenergy, the ultimate success of freshwater macroalgae as a biofuel feedstock will depend upon the ability to produce biomass at the commercial-scale in a cost-effective and sustainable manner. Aquatic ecology can play an important role to achieve the scale-up of algal crop production by informing the supply rates of nutrients to the cultivation systems, and by helping to create adaptive production systems that are resilient to

Benchmarking survey for recycling.

Energy Technology Data Exchange (ETDEWEB)

Marley, Margie Charlotte; Mizner, Jack Harry

2005-06-01

This report describes the methodology, analysis and conclusions of a comparison survey of recycling programs at ten Department of Energy sites including Sandia National Laboratories/New Mexico (SNL/NM). The goal of the survey was to compare SNL/NM's recycling performance with that of other federal facilities, and to identify activities and programs that could be implemented at SNL/NM to improve recycling performance.

Reverse logistics system and recycling potential at a landfill: A case study from Kampala City

International Nuclear Information System (INIS)

Kinobe, J.R.; Gebresenbet, G.; Niwagaba, C.B.; Vinnerås, B.

2015-01-01

Highlights: • Quantifies the different waste streams delivered at the landfill. • Evaluates the amount of potential waste products that enters into the reverse cycle. • Drawing out the reverse logistics activities from Kampala City to Kiteezi landfill. • Identify the storage, collection and transportation mechanisms of products to the various destinations; and finally. • The study suggests efficient measures to improve reverse logistics system. - Abstract: The rapid growing population and high urbanisation rates in Sub-Saharan Africa has caused enormous pressure on collection services of the generated waste in the urban areas. This has put a burden on landfilling, which is the major waste disposal method. Waste reduction, re-use and recycling opportunities exist but are not fully utilized. The common items that are re-used and re-cycled are plastics, paper, aluminum, glass, steel, cardboard, and yard waste. This paper develops an overview of reverse logistics at Kiteezi landfill, the only officially recognised waste disposal facility for Kampala City. The paper analyses, in details the collection, re-processing, re-distribution and final markets of these products into a reversed supply chain network. Only 14% of the products at Kiteezi landfill are channeled into the reverse chain while 63% could be included in the distribution chain but are left out and disposed of while the remaining 23% is buried. This is because of the low processing power available, lack of market value, lack of knowledge and limited value addition activities to the products. This paper proposes possible strategies of efficient and effective reverse logistics development, applicable to Kampala City and other similar cities

Reverse logistics system and recycling potential at a landfill: A case study from Kampala City

Energy Technology Data Exchange (ETDEWEB)

Kinobe, J.R., E-mail: joel.kinobe@slu.se [Department of Energy and Technology, Swedish University of Agricultural Sciences, P.O. Box 7032, SE-750 07 Uppsala (Sweden); Department of Civil and Environmental Engineering, Makerere University College of Engineering, Design, Art and Technology (CEDAT), P.O. Box 7062, Kampala (Uganda); Gebresenbet, G. [Department of Energy and Technology, Swedish University of Agricultural Sciences, P.O. Box 7032, SE-750 07 Uppsala (Sweden); Niwagaba, C.B. [Department of Civil and Environmental Engineering, Makerere University College of Engineering, Design, Art and Technology (CEDAT), P.O. Box 7062, Kampala (Uganda); Vinnerås, B. [Department of Energy and Technology, Swedish University of Agricultural Sciences, P.O. Box 7032, SE-750 07 Uppsala (Sweden)

2015-08-15

Highlights: • Quantifies the different waste streams delivered at the landfill. • Evaluates the amount of potential waste products that enters into the reverse cycle. • Drawing out the reverse logistics activities from Kampala City to Kiteezi landfill. • Identify the storage, collection and transportation mechanisms of products to the various destinations; and finally. • The study suggests efficient measures to improve reverse logistics system. - Abstract: The rapid growing population and high urbanisation rates in Sub-Saharan Africa has caused enormous pressure on collection services of the generated waste in the urban areas. This has put a burden on landfilling, which is the major waste disposal method. Waste reduction, re-use and recycling opportunities exist but are not fully utilized. The common items that are re-used and re-cycled are plastics, paper, aluminum, glass, steel, cardboard, and yard waste. This paper develops an overview of reverse logistics at Kiteezi landfill, the only officially recognised waste disposal facility for Kampala City. The paper analyses, in details the collection, re-processing, re-distribution and final markets of these products into a reversed supply chain network. Only 14% of the products at Kiteezi landfill are channeled into the reverse chain while 63% could be included in the distribution chain but are left out and disposed of while the remaining 23% is buried. This is because of the low processing power available, lack of market value, lack of knowledge and limited value addition activities to the products. This paper proposes possible strategies of efficient and effective reverse logistics development, applicable to Kampala City and other similar cities.

Nutrient composition of important fish species in Bangladesh and potential contribution to recommended nutrient intakes

DEFF Research Database (Denmark)

Bogard, Jessica R.; Thilsted, Shakuntala H.; Marks, Geoffrey C.

2015-01-01

Fish, in Bangladesh where malnutrition remains a significant development challenge, is an irreplaceable animal-source food in the diet of millions. However, existing data on the nutrient composition of fish do not reflect the large diversity available and have focused on only a few select nutrien...... indigenous species, which should guide policy and programmes to improve food and nutrition security in Bangladesh....

Recycling attitudes and behavior among a clinic-based sample of low-income Hispanic women in southeast Texas.

Science.gov (United States)

Pearson, Heidi C; Dawson, Lauren N; Radecki Breitkopf, Carmen

2012-01-01

We examined attitudes and behavior surrounding voluntary recycling in a population of low-income Hispanic women. Participants (N = 1,512) 18-55 years of age completed a self-report survey and responded to questions regarding household recycling behavior, recycling knowledge, recycling beliefs, potential barriers to recycling (transportation mode, time), acculturation, demographic characteristics (age, income, employment, marital status, education, number of children, birth country), and social desirability. Forty-six percent of participants (n = 810) indicated that they or someone else in their household recycled. In a logistic regression model controlling for social desirability, recycling behavior was related to increased age (Precycle (Precycling saves landfill space (Precycling takes too much time (Precycling knowledge and recycling behavior (Precycling behavior among Hispanic women and highlight the need for educational outreach and intervention strategies to increase recycling behavior within this understudied population.

Recycling Attitudes and Behavior among a Clinic-Based Sample of Low-Income Hispanic Women in Southeast Texas

Science.gov (United States)

Pearson, Heidi C.; Dawson, Lauren N.; Radecki Breitkopf, Carmen

2012-01-01

We examined attitudes and behavior surrounding voluntary recycling in a population of low-income Hispanic women. Participants (N = 1,512) 18–55 years of age completed a self-report survey and responded to questions regarding household recycling behavior, recycling knowledge, recycling beliefs, potential barriers to recycling (transportation mode, time), acculturation, demographic characteristics (age, income, employment, marital status, education, number of children, birth country), and social desirability. Forty-six percent of participants (n = 810) indicated that they or someone else in their household recycled. In a logistic regression model controlling for social desirability, recycling behavior was related to increased age (Precycle (Precycling saves landfill space (Precycling takes too much time (Precycling knowledge and recycling behavior (Precycling behavior among Hispanic women and highlight the need for educational outreach and intervention strategies to increase recycling behavior within this understudied population. PMID:22493693

A tale of five cities: Using recycling frameworks to analyse inclusive recycling performance.

Science.gov (United States)

Scheinberg, Anne; Simpson, Michael

2015-11-01

'Recycling' is a source of much confusion, particularly when comparing solid waste systems in high-income countries with those in low- and middle-income countries. Few analysts can explain why the performance and structure of recycling appears to be so different in rich countries from poor ones, nor why well-meaning efforts to implement recycling so often fail. The analysis of policy drivers, and the Integrated Sustainable Waste Management (ISWM) framework, come close to an explanation.This article builds on these earlier works, focusing in on five cities profiled in the 2010 UN-Habitat publication (Scheinberg A, Wilson DC and Rodic L (2010) Solid Waste Management in the World's Cities. UN-Habitat's Third Global Report on the State of Water and Sanitation in the World's Cities. Newcastle-on-Tyne, UK: Earthscan Publications). Data from these cities and others provides the basis for developing a new tool to analyse inclusive recycling performance. The points of departure are the institutional and economic relationships between the service chain, the public obligation to remove waste, pollution, and other forms of disvalue, and the value chain, a system of private enterprises trading valuable materials and providing markets for recyclables. The methodological innovation is to use flows of materials and money as indicators of institutional relationships, and is an extension of process flow diagramming.The authors are using the term 'recycling framework analysis' to describe this new form of institutional analysis. The diagrams increase our understanding of the factors that contribute to high-performance inclusive recycling. By focusing on institutional relationships, the article seeks to improve analysis, planning, and ultimately, outcomes, of recycling interventions. © The Author(s) 2015.

Microalgae growth on the aqueous phase from Hydrothermal Liquefaction of the same microalgae

NARCIS (Netherlands)

Garcia Alba, Laura; Torri, Cristian; Fabbri, Daniele; Kersten, Sascha R.A.; Brilman, Derk Willem Frederik

2013-01-01

Cultivation of Desmodesmus sp. microalgae in the recycled aqueous phase (AP) recovered after Hydrothermal Liquefaction (HTL) of the same microalgae was studied to evaluate the potential of nutrients recycling. AP dilution ratio was systematically varied, using either water or water enriched with

Nutrient enrichment alters storage and fluxes of detritus in a headwater stream ecosystem

Science.gov (United States)

Jonathan P. Benstead; Amy D. Rosemond; Wyatt F. Cross; J. Bruce Wallace; Susan L. Eggert; Keller Suberkropp; Vladislav Gulis; Jennifer L. Greenwood; Cynthia J. Tant

2009-01-01

Responses of detrital pathways to nutrients may differ fundamentally from pathways involving living plants: basal carbon resources can potentially decrease rather than increase with nutrient enrichment. Despite the potential for nutrients to accelerate heterotrophic processes and fluxes of detritus, few studies have examined detritus-nutrient dynamics at whole-...

Resource Efficient Metal and Material Recycling

Science.gov (United States)

Reuter, Markus A.; van Schaik, Antoinette

Metals enable sustainability through their use and their recyclability. However, various factors can affect the Resource Efficiency of Metal Processing and Recycling. Some typical factors that enable Resource Efficiency include and arranged under the drivers of sustainability: Environment (Maximize Resource Efficiency — Energy, Recyclates, Materials, Water, Sludges, Emissions, Land); Economic Feasibility (BAT & Recycling Systems Simulation / Digitalization, Product vis-à-vis Material Centric Recycling); and Social — Licence to Operate (Legislation, consumer, policy, theft, manual labour.). In order to realize this primary production has to be linked systemically with typical actors in the recycling chain such as Original Equipment Manufacturers (OEMs), Recyclers & Collection, Physical separation specialists as well as process metallurgical operations that produce high value metals, compounds and products that recycle back to products. This is best done with deep knowledge of multi-physics, technology, product & system design, process control, market, life cycle management, policy, to name a few. The combination of these will be discussed as Design for Sustainability (DfS) and Design for Recycling (DfR) applications.

Anoxic monimolimnia: Nutrients devious feeders or bombs ready to explode?

Science.gov (United States)

Gianni, Areti; Zacharias, Ierotheos

2015-04-01

Coastal regions are under strong human influence and its environmental impact is reflected into their water quality. Oligotrophic estuaries and coastal systems have changed in mesotrophic and/or eutrophic, shown an increase in toxic algal blooms, hypoxic/anoxic events, and massive mortalities of many aquatic and benthic organisms. In strongly stratified and productive water basins, bottom water dissolved oxygen is depleted due to the excessive organic matter decomposition in these depths. Distribution and recycling of nutrients in their water column is inextricably dependent on oxygenation and redox conditions. Bottom water anoxia accelerates PO43-, NH4+ and H2S recycling and accumulation from organic matter decomposition. The anoxic, H2S, PO43- and NH4+ rich bottom water constitutes a toxic layer, threatening the balance of the entire ecosystem. In permanently stratified water basins, storm events could result in stratification destruction and water column total mixing. The turnover brings large amounts of H2S to the surface resulting in low levels of oxygen and massive fish kills. PO43- and NH4+ are released to the interface and surface waters promoting algal blooms. Μore organic matter is produced fueling anoxia. The arising question is, whether the balance of an anoxic water ecosystem is under the threat of its hypolimnetic nutrient and sulfide load, only in the case of storm events and water column total mixing. In polymictic water basins it is clear that the accumulated, in the bottom layer, nutrients will supply surface waters, after the pycnocline overturn. Besides this mechanism of basins' water quality degradation is nowadays recognized as one of the biggest obstacles in eutrophic environments management and restoration efforts. The role of internal load, in permanently stratified water basins, is not so clear. In the present study the impact of storm events on water column stability and bottom water anoxia of meromictic coastal basins, is investigated

Emergy analysis of the recycling options for construction and demolition waste.

Science.gov (United States)

Yuan, Fang; Shen, Li-yin; Li, Qi-ming

2011-12-01

Construction and demolition (C&D) waste is becoming a major contributor to environmental pollution. In Shanghai, China, the quantity of C&D waste is 2.11E+07 t/yr, which accounts for 45% of the total quantity of solid waste. There has been a growing promotion of recycling C&D waste as an effective way to solve this waste problem. However, the evaluation of the efficiency of recycling C&D waste as a potential source of resources is largely based on traditional economic analysis. The economic analysis emphasizes money instead of the harmony between economic benefit and environmental effects. There is a need for a new strategic approach to investigate the efficiency of recycling C&D waste to achieve the integration between economic, social and environmental effects. Emergy theory can be employed to analyze different recycling options for C&D waste. With reference to the Chinese construction industry, this paper demonstrates that the close-loop recycling option is better than the open-loop recycling option for C&D waste in terms of the integration of social, environmental and sustainable aspects. To evaluate different technology solutions for C&D waste recycling, the emergy theory and method is not limited to a cost-benefit balance but can include economic, social, environmental and sustainable effects. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nutrient supply of plants in aquaponic systems

Directory of Open Access Journals (Sweden)

Andras Bittsanszky

2016-10-01

Full Text Available In this preliminary article we present data on plant nutrient concentrations in aquaponics systems, and we compare them to nutrient concentrations in “standard” hydroponic solutions. Our data shows that the nutrient concentrations supplied by the fish in the aquaponics system are significantly lower for most nutrients compared to hydroponic systems. Nevertheless, plants do thrive in solutions that have lower nutrient levels compared to “standard” hydroponic solutions. This is especially true for green leafy vegetables that rarely need additional nutritional supplementation. It is concluded that in the highly complex system of aquaponics, special care has to be taken, via continuous monitoring of the chemical composition of the circulating water, to provide adequate concentrations and ratios of nutrients, and especially for the potentially toxic component, ammonium. If certain plants require nutrient supplementation, we consider that one based on organic substances would be most beneficial. However, protocols for the application of such nutrient amendments still need to be developed.

High nutrient transport and cycling potential revealed in the microbial metagenome of Australian sea lion (Neophoca cinerea) faeces.

Science.gov (United States)

Lavery, Trish J; Roudnew, Ben; Seymour, Justin; Mitchell, James G; Jeffries, Thomas

2012-01-01

Metagenomic analysis was used to examine the taxonomic diversity and metabolic potential of an Australian sea lion (Neophoca cinerea) gut microbiome. Bacteria comprised 98% of classifiable sequences and of these matches to Firmicutes (80%) were dominant, with Proteobacteria and Actinobacteria representing 8% and 2% of matches respectively. The relative proportion of Firmicutes (80%) to Bacteriodetes (2%) is similar to that in previous studies of obese humans and obese mice, suggesting the gut microbiome may confer a predisposition towards the excess body fat that is needed for thermoregulation within the cold oceanic habitats foraged by Australian sea lions. Core metabolic functions, including carbohydrate utilisation (14%), protein metabolism (9%) and DNA metabolism (7%) dominated the metagenome, but in comparison to human and fish gut microbiomes there was a significantly higher proportion of genes involved in phosphorus metabolism (2.4%) and iron scavenging mechanisms (1%). When sea lions defecate at sea, the relatively high nutrient metabolism potential of bacteria in their faeces may accelerate the dissolution of nutrients from faecal particles, enhancing their persistence in the euphotic zone where they are available to stimulate marine production.

Expanded recycling at Los Alamos National Laboratory

International Nuclear Information System (INIS)

Betschart, J.F.; Malinauskas, L.; Burns, M.

1996-01-01

The Pollution Prevention Program Office has increased recycling activities, reuse, and options to reduce the solid waste streams through streamlining efforts that applied best management practices. The program has prioritized efforts based on volume and economic considerations and has greatly increased Los Alamos National Laboratory's (LANL's) recycle volumes. The Pollution Prevention Program established and chairs a Solid Waste Management Solutions Group to specifically address and solve problems in nonradioactive, Resource Conservation and Recovery Act (RCRA), state-regulated, and sanitary and industrial waste streams (henceforth referred to as sanitary waste in this paper). By identifying materials with recycling potential, identifying best management practices and pathways to return materials for reuse, and introducing the concept and practice of open-quotes asset management,open-quotes the Group will divert much of the current waste stream from disposal. This Group is developing procedures, agreements, and contracts to stage, collect, sort, segregate, transport and process materials, and is also garnering support for the program through the involvement of upper management, facility managers, and generators

Printability of papers recycled from toner and inkjet-printed papers after deinking and recycling processes.

Science.gov (United States)

Karademir, Arif; Aydemir, Cem; Tutak, Dogan; Aravamuthan, Raja

2018-04-01

In our contemporary world, while part of the fibers used in the paper industry is obtained from primary fibers such as wood and agricultural plants, the rest is obtained from secondary fibers from waste papers. To manufacture paper with high optical quality from fibers of recycled waste papers, these papers require deinking and bleaching of fibers at desired levels. High efficiency in removal of ink from paper mass during recycling, and hence deinkability, are especially crucial for the optical and printability quality of the ultimate manufactured paper. In the present study, deinkability and printability performance of digitally printed paper with toner or inkjet ink were compared for the postrecycling product. To that end, opaque 80 g/m 2 office paper was digitally printed under standard printing conditions with laser toner or inkjet ink; then these sheets of paper were deinked by a deinking process based on the INGEDE method 11 p. After the deinking operation, the optical properties of the obtained recycled handsheets were compared with unprinted (reference) paper. Then the recycled paper was printed on once again under the same conditions as before with inkjet and laser printers, to monitor and measure printing color change before and after recycling, and differences in color universe. Recycling and printing performances of water-based inkjet and toner-based laser printed paper were obtained. The outcomes for laser-printed recycled paper were better than those for inkjet-printed recycled paper. Compared for luminosity Y, brightness, CIE a* and CIE b* values, paper recycled from laser-printed paper exhibited higher value than paper recycled from inkjet-printed paper.

Effects of potential once-through improvements on the uranium utilization in the closed LWR cycle assuming self generated recycling of uranium and plutonium

International Nuclear Information System (INIS)

1979-06-01

This paper is concerned with potential improvements to the resource utilization of current generation light water reactors operating on a closed U/Pu fuel cycle. Only those modifications to existing systems layout and fuel cycle practise are discussed that have been considered in Working Group 8 A for the once-through cycle. The objective is to give an impression how much the difference in resource utilization between the once-through and the closed U/Pu cycle were changed if both cycles were reoptimized independantly from each other with respect to uranium consumption. No commercial recycling of U/Pu has been taken place to date in 1300 MWe light water reactors. The feasibility of thermal recycling has been demonstrated however on an industrial scale in reactors of the 300 MWe class. (Obrigheim, Gundremmingen). From this experience and from extensive design calculations it has been concluded that for Pu bearing fuel assemblies of 1300 MWe plants it would be favorable to use the same structural layout and similar fuel management procedures as for uranium assemblies. This would result in plant life-time averaged uranium savings on the order of 35 - 40 % relative to the once-through cycle in case of the Self Generated Recycling Mode

Recycling of Glass

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Damgaard, Anders

2011-01-01

Glass is used for many purposes, but in the waste system glass is predominantly found in terms of beverage and food containers with a relatively short lifetime before ending up in the waste. Furthermore there is a large amount of flat glass used in building materials which also ends up in the waste...... system; this glass though has a long lifetime before ending up in the waste. Altogether these product types add up to 82% of the production of the European glass industry (IPCC, 2001). Recycling of glass in terms of cleaning and refilling of bottles as well as the use of broken glass in the production...... of new glass containers is well established in the glass industry. This chapter describes briefly howglass is produced and howwaste glass is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of glass recycling....

Recycled materials in geotechnical applications. Geotechnical special publication No. 79

Energy Technology Data Exchange (ETDEWEB)

Vipulanandan, C.; Elton, D.J. [eds.

1998-07-01

Recycled materials have the potential for use in a variety of geotechnical and geoenvironmental applications. This proceedings contains 15 papers on field applications and laboratory testing related to recycled materials. Papers cover: geotechnics of industrial by-products; paper mill sludge for landfill cover; mitigation of void development under bridge approach slabs using rubber tire chips; tire shreds as lightweight fill for embankments and retaining walls; performance of a highway embankment and hydraulic barriers constructed using waste foundry sand, and recycled materials; lagoon-stored lime for embankment; construction and demolition debris for base and subbase applications; fly ash for fill, pavement, earth structures and aggregate; compaction of contaminated soils-reuse as a road base material; and database on beneficial reuse of foundry by-products; and more.

COPPER CABLE RECYCLING TECHNOLOGY

International Nuclear Information System (INIS)

Chelsea Hubbard

2001-01-01

The United States Department of Energy (DOE) continually seeks safer and more cost-effective technologies for use in deactivation and decommissioning (D and D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE's Office of Science and Technology (OST) sponsors large-scale demonstration and deployment projects (LSDDPs). At these LSDDPs, developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to the DOE's projects and to others in the D and D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, and decreased costs of operation. The Idaho National Engineering and Environmental Laboratory (INEEL) generated a list of statements defining specific needs and problems where improved technology could be incorporated into ongoing D and D tasks. One such need is to reduce the volume of waste copper wire and cable generated by D and D. Deactivation and decommissioning activities of nuclear facilities generates hundreds of tons of contaminated copper cable, which are sent to radioactive waste disposal sites. The Copper Cable Recycling Technology separates the clean copper from contaminated insulation and dust materials in these cables. The recovered copper can then be reclaimed and, more importantly, landfill disposal volumes can be reduced. The existing baseline technology for disposing radioactively contaminated cables is to package the cables in wooden storage boxes and dispose of the cables in radioactive waste disposal sites. The Copper Cable Recycling Technology is applicable to facility decommissioning projects at many Department of Energy (DOE) nuclear facilities and commercial nuclear power plants undergoing decommissioning activities. The INEEL Copper Cable Recycling Technology Demonstration investigated the effectiveness and efficiency to recycle 13.5 tons of copper cable. To determine the effectiveness

You're a "What"? Recycling Coordinator

Science.gov (United States)

Torpey, Elka Maria

2011-01-01

Recycling coordinators supervise curbside and dropoff recycling programs for municipal governments or private firms. Today, recycling is mandatory in many communities. And advancements in collection and processing methods have helped to increase the quantity of materials for which the recycling coordinator is responsible. In some communities,…

The role of isotopes in studying nutrient and organic matter dynamics in livestock/cropping systems, with emphasis on carbon and nitrogen

International Nuclear Information System (INIS)

Ledgard, Stewart F.

2002-01-01

valuable information on the root carbon pools and turnover rates for different plant systems. In livestock research, isotopes have been used to determine the relative conversion of dietary nutrients into animal produce, animal tissues, dung and urine. However, this is more commonly determined using non-isotopic studies with stall fed animals and nutrient analysis of the various components. Isotopic studies of this kind are most valuable for detailed research tracing nutrient conversion into specific animal components or metabolites. Several studies have used 15 N-enriched plant material fed to animals to generate 15 N-labelled excreta for research on the fate of excreta N. Quality of the feed source for livestock can have a marked effect on the relative conversion of feed N into animal produce, dung or urine. While this has been well researched in intensive livestock systems in developed countries, there is much less information on the fate of feed N consumed by animals in developing countries where poor quality feed sources may be used. In the latter, more than half of the consumed N can be excreted in dung and this represents an important potential source of N and other nutrients for recycling onto crops. The system of animal management influences the recovery of nutrients in manure. In developing countries, such as in Africa, animals may be penned continuously and the manure is collected, stored and applied onto cropping areas. The storage method and treatment of manure (e.g. straw may be mixed with it) will influence the temporal availability of nutrients after application to soil. Detailed research is required to better understand the variability in N supply from manures in relation to feed quality and to develop practical recommendation systems for their optimum use in cropping systems. The stable isotopes 15 N and 13 C can play a valuable role in such research programmes. Research requirements in developing counties should be based on local knowledge and

Recyclable organic solar cells on cellulose nanocrystal substrates.

Science.gov (United States)

Zhou, Yinhua; Fuentes-Hernandez, Canek; Khan, Talha M; Liu, Jen-Chieh; Hsu, James; Shim, Jae Won; Dindar, Amir; Youngblood, Jeffrey P; Moon, Robert J; Kippelen, Bernard

2013-01-01

Solar energy is potentially the largest source of renewable energy at our disposal, but significant advances are required to make photovoltaic technologies economically viable and, from a life-cycle perspective, environmentally friendly, and consequently scalable. Cellulose nanomaterials are emerging high-value nanoparticles extracted from plants that are abundant, renewable, and sustainable. Here, we report on the first demonstration of efficient polymer solar cells fabricated on optically transparent cellulose nanocrystal (CNC) substrates. The solar cells fabricated on the CNC substrates display good rectification in the dark and reach a power conversion efficiency of 2.7%. In addition, we demonstrate that these solar cells can be easily separated and recycled into their major components using low-energy processes at room temperature, opening the door for a truly recyclable solar cell technology. Efficient and easily recyclable organic solar cells on CNC substrates are expected to be an attractive technology for sustainable, scalable, and environmentally-friendly energy production.

WATER RESISTANCE OF RECYCLED PAPER PANEL

Directory of Open Access Journals (Sweden)

Alexander Rani Suryandono

2017-06-01

Alice Wisler (2015 Facts about Recycling Paper. http://greenliving.lovetoknow.com/Facts_About_Recycling_Paper. Accessed 2 April 2016 Clay Miller (2011 5 Benefits of Recycling Paper. http://www.ways2gogreenblog.com/2011/09/28/5-benefits-of-recycling-paper/. Accessed 10 May 2016 Hari Goyal (2015 Grades of Paper. http://www.paperonweb.com/grade.htm. Accessed 2 April 2016 Hari Goyal (2015 Properties of Paper. http://www.paperonweb.com/paperpro.htm. Accessed 2 April 2016 Kathryn Sukalich (2016 Everything You Need to Know about Paper Recycling. http://earth911.com/business-policy/business/paper-recycling-details-basics/. Accessed 15 July 2016 [U1] Larry West (2015 Why Recycle Paper. http://environment.about.com/od/recycling/a/The-Benefits-Of-Paper-Recycling-Why-Recycle-Paper.htm. Accesed 15 June 2016 Marie-Luise Blue (2008 The Advantages of Recycling Paper. http://education.seattlepi.com/advantages-recycling-paper-3440.html. Accessed 15 June 2016 Nina Spitzer (2009 http://www.sheknows.com/home-and-gardening/articles/810025/the-impact-of-disposable-coffee-cups-on-the-environment. Accessed 15 June 2016 Radio New Zealand (2010 Iwi not Giving Up Fight against Tasman Mill Discharges. http://www.radionz.co.nz/news/regional/64521/iwi-not-giving-up-fight-against-tasman-mill-discharges. Accessed 15 July 2016 Rick LeBlanc (2016 Paper Recycling Facts, Figures and Information Sources. https://www.thebalance.com/paper-recycling-facts-figures-and-information-sources-2877868?_ga=1.192832942.544061388.1477446686. Accesed 2 April 2016 Robinson Meyer (2016 Will More Newspapers Go Nonprofit? http://www.theatlantic.com/technology/archive/2016/01/newspapers-philadelphia-inquirer-daily-news-nonprofit-lol-taxes/423960/. Accessed 3 August 2016 School of Engineering at Darthmouth (2010 Forest and Paper Industry. http://engineering.dartmouth.edu/~d30345d/courses/engs171/Paper.pdf. Accessed 2 April 2016 T. Subramani, V. Angappan. (2015. Experimental Investigation of Papercrete Concrete

Comparison between disintegrated and fermented sewage sludge for production of a carbon source suitable for biological nutrient removal.

Science.gov (United States)

Soares, Ana; Kampas, Pantelis; Maillard, Sarah; Wood, Elizabeth; Brigg, Jon; Tillotson, Martin; Parsons, Simon A; Cartmell, Elise

2010-03-15

There is a need to investigate processes that enable sludge re-use while enhancing sewage treatment efficiency. Mechanically disintegrated thickened surplus activated sludge (SAS) and fermented primary sludge were compared for their capacity to produce a carbon source suitable for BNR by completing nutrient removal predictive tests. Mechanically disintegration of SAS using a deflaker enhanced volatile fatty acids (VFAs) content from 92 to 374 mg l(-1) (4.1-fold increase). In comparison, primary sludge fermentation increased the VFAs content from 3.5 g l(-1) to a final concentration of 8.7 g l(-1) (2.5-fold increase). The carbon source obtained from disintegration and fermentation treatments improved phosphate (PO(4)-P) release and denitrification by up to 0.04 mg NO(3)-Ng(-1)VSS min(-1) and 0.031 mg PO(4)-Pg(-1)VSS min(-1), respectively, in comparison to acetate (0.023 mg NO(3)-Ng(-1)VSS min(-1)and 0.010 mg PO(4)-Pg(-1)VSS min(-1)). Overall, both types of sludge were suitable for BNR but disintegrated SAS displayed lower carbon to nutrient ratios of 8 for SCOD:PO(4)-P and 9 for SCOD:NO(3)-N. On the other hand, SAS increased the concentration of PO(4)-P in the settled sewage by a further 0.97 g PO(4)-P kg(-1)SCOD indicating its potential negative impact towards nutrient recycling in the BNR process. (c) 2009 Elsevier B.V. All rights reserved.

Technology options for future recycling

International Nuclear Information System (INIS)

Kikuchi, T.

2001-01-01

Recycling of nuclear material is indispensable, not only for using valuable resources but also for reducing the debt which we may leave to the next generations. Advanced reprocessing technologies have been developed in several countries to deal with the diversification of nuclear fuels. Also technologies derived from reprocessing or other fuel cycle areas have continued to be developed in terms of recycling. Cost effectiveness and waste-free processing are increasingly important factors in the applicable of an alternate recycling policy. This paper introduces an example of the studies in this field conducted in some countries including Japan and considers the establishment of effective recycling methodologies taking into account the uncertainty of future recycling policy. (author)

Impact of minor actinide recycling on sustainable fuel cycle options

Energy Technology Data Exchange (ETDEWEB)

Heidet, F.; Kim, T. K.; Taiwo, T. A.

2017-11-01

the repository performance. On the other hand, recycling minor actinides also results in an increase of the recycled fuel characteristics and therefore of the charged fuel. The radioactivity is slightly increased while the decay heat and radiotoxicities are very significantly increased. Despite these differences, the characteristics of the fuel at time of discharge remain similar whether minor actinides are recycled or not, with the exception of the inhalation radiotoxicity which is significantly larger with minor actinide recycling. After some cooling the characteristics of the discharged fuel become larger when minor actinides are recycled, potentially affecting the reprocessing plant requirements. Recycling minor actinides has a negative impact on the characteristics of the fresh fuel and will make it more challenging to fabricate fuel containing minor actinides.

The nonlinear relationship between paper recycling and primary pulp requirements : modeling paper production and recycling in Europe

NARCIS (Netherlands)

Schenk, Niels J.; Moll, Henri C.; Potting, Josepha

Waste paper is suitable for recycling back into paper or for incineration for energy recovery. If waste paper is used for recycling, secondary pulp replaces virgin pulp. Fiber recycling is limited, however, because of physical constraints—particularly the breakage of fiber in the recycling

The Three Rs: Reduce, Reuse, Recycle.

Science.gov (United States)

Science Activities, 1991

1991-01-01

A student hand-out for a recycling unit defines the terms reduce, recycle, and reuse as they relate to solid waste management. Presents the characteristics of recyclable items such as yard wastes, metals, glass, and paper. Lists organizations through which more information about recycling can be obtained. (MCO)

Soil contamination from lead battery manufacturing and recycling in seven African countries.

Science.gov (United States)

Gottesfeld, Perry; Were, Faridah Hussein; Adogame, Leslie; Gharbi, Semia; San, Dalila; Nota, Manti Michael; Kuepouo, Gilbert

2018-02-01

Lead battery recycling is a growing hazardous industry throughout Africa. We investigated potential soil contamination inside and outside formal sector recycling plants in seven countries. We collected 118 soil samples at 15 recycling plants and one battery manufacturing site and analyzed them for total lead. Lead levels in soils ranged from battery industry in Africa continues to expand, it is expected that the number and size of lead battery recycling plants will grow to meet the forecasted demand. There is an immediate need to address ongoing exposures in surrounding communities, emissions from this industry and to regulate site closure financing procedures to ensure that we do not leave behind a legacy of lead contamination that will impact millions in communities throughout Africa. Copyright © 2017 Elsevier Inc. All rights reserved.

Reuse, Reduce, Recycle.

Science.gov (United States)

Briscoe, Georgia

1991-01-01

Discussion of recycling paper in law libraries is also applicable to other types of libraries. Results of surveys of law libraries that investigated recycling practices in 1987 and again in 1990 are reported, and suggestions for reducing the amount of paper used and reusing as much as possible are offered. (LRW)

Linking phylogenetic and functional diversity to nutrient spiraling in microbial mats from Lower Kane Cave (USA).

Science.gov (United States)

Engel, Annette Summers; Meisinger, Daniela B; Porter, Megan L; Payn, Robert A; Schmid, Michael; Stern, Libby A; Schleifer, K H; Lee, Natuschka M

2010-01-01

Microbial mats in sulfidic cave streams offer unique opportunities to study redox-based biogeochemical nutrient cycles. Previous work from Lower Kane Cave, Wyoming, USA, focused on the aerobic portion of microbial mats, dominated by putative chemolithoautotrophic, sulfur-oxidizing groups within the Epsilonproteobacteria and Gammaproteobacteria. To evaluate nutrient cycling and turnover within the whole mat system, a multidisciplinary strategy was used to characterize the anaerobic portion of the mats, including application of the full-cycle rRNA approach, the most probable number method, and geochemical and isotopic analyses. Seventeen major taxonomic bacterial groups and one archaeal group were retrieved from the anaerobic portions of the mats, dominated by Deltaproteobacteria and uncultured members of the Chloroflexi phylum. A nutrient spiraling model was applied to evaluate upstream to downstream changes in microbial diversity based on carbon and sulfur nutrient concentrations. Variability in dissolved sulfide concentrations was attributed to changes in the abundance of sulfide-oxidizing microbial groups and shifts in the occurrence and abundance of sulfate-reducing microbes. Gradients in carbon and sulfur isotopic composition indicated that released and recycled byproduct compounds from upstream microbial activities were incorporated by downstream communities. On the basis of the type of available chemical energy, the variability of nutrient species in a spiraling model may explain observed differences in microbial taxonomic affiliations and metabolic functions, thereby spatially linking microbial diversity to nutrient spiraling in the cave stream ecosystem.

Recycling of plastic waste: Presence of phthalates in plastics from households and industry

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Eriksen, Marie Kampmann; Martín-Fernández, J. A.

2016-01-01

recognised, the influence of plastic recycling on phthalate content has been hypothesised but not well documented. In the present work we analysed selected phthalates (DMP, DEP, DPP, DiBP, DBP, BBzP, DEHP, DCHP and DnOP) in samples of waste plastics as well as recycled and virgin plastics. DBP, DiBP and DEHP...... product manufacturing (labelling, gluing, etc.) and were not removed following recycling of household waste plastics. Furthermore, DEHP was identified as a potential indicator for phthalate contamination of plastics. Close monitoring of plastics intended for phthalates-sensitive applications...

Reclaim/recycle of Pt/C catalysts for PEMFC

International Nuclear Information System (INIS)

Zhao, Jishi; He, Xiangming; Tian, Jianhua; Wan, Chunrong; Jiang, Changyin

2007-01-01

Platinum was reclaimed from Pt/C catalysts of the PEMFC by drying the degraded Pt/C catalysts at 80 o C for 3 h, followed by sintering at 600 o C for 6 h, dissolution by aqua fortis, purification with hydrochloric acid, reduction and filtration, successively. Pt/C catalysts were prepared again from the reclaimed Pt by two proposed processes, e.g., pH value control process and mass control process. The fuel cell with recycled catalysts presented a power density of over 0.18 W cm -2 . The reclaiming of Pt/C catalysts is a potential way for recycling Pt for PEMFC, reducing the cost of PEMFC

Molecular composition of recycled organic wastes, as determined by solid-state 13C NMR and elemental analyses

International Nuclear Information System (INIS)

Eldridge, S.M.; Chen, C.R.; Xu, Z.H.; Nelson, P.N.; Boyd, S.E.; Meszaros, I.; Chan, K.Y.

2013-01-01

Highlights: • Model estimated the molecular C components well for most RO wastes. • Molecular nature of organic matter in RO wastes varied widely. • Molecular composition by NMR modelling preferable to extraction techniques. • Some model shortcomings in estimating molecular composition of biochars. • Waste molecular composition important for carbon/nutrient outcomes in soil. - Abstract: Using solid state 13 C NMR data and elemental composition in a molecular mixing model, we estimated the molecular components of the organic matter in 16 recycled organic (RO) wastes representative of the major materials generated in the Sydney basin area. Close correspondence was found between the measured NMR signal intensities and those predicted by the model for all RO wastes except for poultry manure char. Molecular nature of the organic matter differed widely between the RO wastes. As a proportion of organic C, carbohydrate C ranged from 0.07 to 0.63, protein C from <0.01 to 0.66, lignin C from <0.01 to 0.31, aliphatic C from 0.09 to 0.73, carbonyl C from 0.02 to 0.23, and char C from 0 to 0.45. This method is considered preferable to techniques involving imprecise extraction methods for RO wastes. Molecular composition data has great potential as a predictor of RO waste soil carbon and nutrient outcomes

Typology of Options for Metal Recycling: Australia’s Perspective

Directory of Open Access Journals (Sweden)

Artem Golev

2015-12-01

Full Text Available While Australia has traditionally relied on obtaining metals from primary sources (namely mined natural resources, there is significant potential to recover metals from end-of-life-products and industrial waste. Although any metals recycling value chain requires a feasible technology at its core, many other non-technical factors are key links in the chain, which can compromise the overall viability to recycle a commodity and/or product. The “Wealth from Waste” Cluster project funded by the Commonwealth Scientific Industrial Research Organisation (CSIRO Flagship Collaboration Fund and partner universities is focusing on identifying viable options to “mine” metals contained in discarded urban infrastructure, manufactured products and consumer goods. A key aspect of this research is to understand the critical non-technical barriers and system opportunities to enhance rates of metals recycling in Australia. Work to date has estimated the mass and current worth of metals in above ground resources. Using these outcomes as a basis, a typology for different options for (metal reuse and recycling has been developed to classify the common features, which is presented in this article. In addition, the authors investigate the barriers and enablers in the recycling value chain, and propose a set of requirements for a feasible pathway to close the material loop for metals in Australia.

Revealing Invisible Water: Moisture Recycling as an Ecosystem Service.

Science.gov (United States)

Keys, Patrick W; Wang-Erlandsson, Lan; Gordon, Line J

2016-01-01

An ecosystem service is a benefit derived by humanity that can be traced back to an ecological process. Although ecosystem services related to surface water have been thoroughly described, the relationship between atmospheric water and ecosystem services has been mostly neglected, and perhaps misunderstood. Recent advances in land-atmosphere modeling have revealed the importance of terrestrial ecosystems for moisture recycling. In this paper, we analyze the extent to which vegetation sustains the supply of atmospheric moisture and precipitation for downwind beneficiaries, globally. We simulate land-surface evaporation with a global hydrology model and track changes to moisture recycling using an atmospheric moisture budget model, and we define vegetation-regulated moisture recycling as the difference in moisture recycling between current vegetation and a hypothetical desert world. Our results show that nearly a fifth of annual average precipitation falling on land is from vegetation-regulated moisture recycling, but the global variability is large, with many places receiving nearly half their precipitation from this ecosystem service. The largest potential impacts for changes to this ecosystem service are land-use changes across temperate regions in North America and Russia. Likewise, in semi-arid regions reliant on rainfed agricultural production, land-use change that even modestly reduces evaporation and subsequent precipitation, could significantly affect human well-being. We also present a regional case study in the Mato Grosso region of Brazil, where we identify the specific moisture recycling ecosystem services associated with the vegetation in Mato Grosso. We find that Mato Grosso vegetation regulates some internal precipitation, with a diffuse region of benefit downwind, primarily to the south and east, including the La Plata River basin and the megacities of Sao Paulo and Rio de Janeiro. We synthesize our global and regional results into a generalized

Technical specifications for mechanical recycling of agricultural plastic waste

International Nuclear Information System (INIS)

Briassoulis, D.; Hiskakis, M.; Babou, E.

2013-01-01

Highlights: • Technical specifications for agricultural plastic wastes (APWs) recycling proposed. • Specifications are the base for best economical and environmental APW valorisation. • Analysis of APW reveals inherent characteristics and constraints of APW streams. • Thorough survey on mechanical recycling processes and industry as it applies to APW. • Specifications for APW recycling tested, adjusted and verified through pilot trials. - Abstract: Technical specifications appropriate for the recycling of agricultural plastic wastes (APWs), widely accepted by the recycling industry were developed. The specifications establish quality standards to be met by the agricultural plastics producers, users and the agricultural plastic waste management chain. They constitute the base for the best economical and environmental valorisation of the APW. The analysis of the APW streams conducted across Europe in the framework of the European project “LabelAgriWaste” revealed the inherent characteristics of the APW streams and the inherent constraints (technical or economical) of the APW. The APW stream properties related to its recycling potential and measured during pilot trials are presented and a subsequent universally accepted simplified and expanded list of APW recycling technical specifications is proposed and justified. The list includes two sets of specifications, applied to two different quality categories of recyclable APW: one for pellet production process (“Quality I”) and another one for plastic profile production process (“Quality II”). Parameters that are taken into consideration in the specifications include the APW physical characteristics, contamination, composition and degradation. The proposed specifications are focused on polyethylene based APW that represents the vast majority of the APW stream. However, the specifications can be adjusted to cover also APW of different materials (e.g. PP or PVC) that are found in very small quantities

The prospect for recycle of radioactive scrap metals to products for restricted and unrestricted use

International Nuclear Information System (INIS)

Liby, A.L.

1995-01-01

Large quantities of radioactive scrap metals will arise from decontamination and decommissioning of nuclear power plants and DOE facilities. Much of this metal can be easily decontaminated and released to the existing secondary metals industry for recycling. For metal that can not be readily released, recycle into restricted-use end products is an economically attractive alternative to burial as low level radioactive waste. This paper will examine sources and types of scrap metal, technical approaches, potential products, and economics of metals recycle. Construction, licensing, environmental compliance, and possible reuse of existing nuclear facilities for metals recycling will be discussed. (author)

Recovering recyclable materials from shredder residue

Science.gov (United States)

Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.; Brockmeier, Norman F.

1994-02-01

Each year, about 11 million tons of metals are recovered in the United States from about 10 million discarded automobiles. The recovered metals account for about 75 percent of the total weight of the discarded vehicles. The balance of the material, known as shredder residue, amounts to about three million tons annually and is currently landfilled. The residue contains a diversity of potentially recyclable materials, including polyurethane foams, iron oxides, and certain thermoplastics. This article discusses a process under development at Argonne National Laboratory to separate and recover the recyclable materials from this waste stream. The process consists essentially of two stages. First, a physical separation is used to recover the foams and the metal oxides, followed by a chemical process to extract certain thermoplastics. The status of the technology and the process economics are reviewed here.

An industry response to recycle 2000

International Nuclear Information System (INIS)

Motl, G.P.; Loiselle, V.

1996-01-01

The US DOE is expected to issue a policy early this year articulating DOE's position on the recycle of DOE radioactive scrap metal. In anticipation of this 'Recycle 2000' initiative, the nuclear industry has formed a new trade association called the Association of Radioactive Metal Recyclers (ARMR). This article describes the Recycle 2000 initiative, provides some background on the ARMR and its membership, and identifies industry views on the actions to be taken and issues to be resolved in Recycle 2000 is to become a reality

Methods to estimate the transfer of contaminants into recycling products - A case study from Austria.

Science.gov (United States)

Knapp, Julika; Allesch, Astrid; Müller, Wolfgang; Bockreis, Anke

2017-11-01

Recycling of waste materials is desirable to reduce the consumption of limited primary resources, but also includes the risk of recycling unwanted, hazardous substances. In Austria, the legal framework demands secondary products must not present a higher risk than comparable products derived from primary resources. However, the act provides no definition on how to assess this risk potential. This paper describes the development of different quantitative and qualitative methods to estimate the transfer of contaminants in recycling processes. The quantitative methods comprise the comparison of concentrations of harmful substances in recycling products to corresponding primary products and to existing limit values. The developed evaluation matrix, which considers further aspects, allows for the assessment of the qualitative risk potential. The results show that, depending on the assessed waste fraction, particular contaminants can be critical. Their concentrations were higher than in comparable primary materials and did not comply with existing limit values. On the other hand, the results show that a long-term, well-established quality control system can assure compliance with the limit values. The results of the qualitative assessment obtained with the evaluation matrix support the results of the quantitative assessment. Therefore, the evaluation matrix can be suitable to quickly screen waste streams used for recycling to estimate their potential environmental and health risks. To prevent the transfer of contaminants into product cycles, improved data of relevant substances in secondary resources are necessary. In addition, regulations for material recycling are required to assure adequate quality control measures, including limit values. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of simulated mechanical recycling processes on the structure and properties of poly(lactic acid).

Science.gov (United States)

Beltrán, F R; Lorenzo, V; Acosta, J; de la Orden, M U; Martínez Urreaga, J

2018-06-15

The aim of this work is to study the effects of different simulated mechanical recycling processes on the structure and properties of PLA. A commercial grade of PLA was melt compounded and compression molded, then subjected to two different recycling processes. The first recycling process consisted of an accelerated ageing and a second melt processing step, while the other recycling process included an accelerated ageing, a demanding washing process and a second melt processing step. The intrinsic viscosity measurements indicate that both recycling processes produce a degradation in PLA, which is more pronounced in the sample subjected to the washing process. DSC results suggest an increase in the mobility of the polymer chains in the recycled materials; however the degree of crystallinity of PLA seems unchanged. The optical, mechanical and gas barrier properties of PLA do not seem to be largely affected by the degradation suffered during the different recycling processes. These results suggest that, despite the degradation of PLA, the impact of the different simulated mechanical recycling processes on the final properties is limited. Thus, the potential use of recycled PLA in packaging applications is not jeopardized. Copyright © 2017 Elsevier Ltd. All rights reserved.

The impact of radioactive steel recycling on the public and professionals

International Nuclear Information System (INIS)

Hrncir, Tomas; Panik, Michal; Ondra, Frantisek; Necas, Vladimir

2013-01-01

Highlights: • Methodology for recycling of decommissioning steel was developed. • Four scenarios of recycling within nuclear and public sector were suggested. • Radiation impact assessment of suggested scenarios was performed. • Conditional clearance levels for analyzed radionuclides were derived. • Results imply that recycling of decommissioning steel can be feasible. -- Abstract: The decommissioning of nuclear power plants represents a complex process resulting in the generation of large amounts of waste materials, e.g. steel scrap containing various concentrations of radionuclides. Recycling some of these materials is highly desirable due to numerous reasons. Herein presented scenarios of recycling of radioactive steel within the nuclear as well as civil engineering industry are analyzed from the radiation protection point of view. An approach based on the dose constraints principle is chosen. The aim of the study is to derive conditional clearance levels (maximal specific mass activity of material allowing its recycling/clearance) for analyzed radionuclides ensuring that the detrimental impact on human health is kept on a negligible level. Determined conditional clearance levels, as the result of performed software calculations, are valid for the reuse of radioactive steel in four selected scenarios. Calculation results indicate that the increase of the amount of recyclable radioactive steel due to its reuse in specific applications may be feasible considering the radiation impact on the public and professionals. However, issues connected with public acceptance, technical difficulties and financing of potential realization are still open and they have to be examined in more detail

Illuminating pathways of forest nutrient provision: relative release from soil mineral and organic pools

Science.gov (United States)

Hauser, E.; Billings, S. A.

2017-12-01

Depletion of geogenic nutrients during soil weathering can prompt vegetation to rely on other sources, such as organic matter (OM) decay, to meet growth requirements. Weathered soils also tend to permit deep rooting, a phenomenon sometimes attributed to vegetation foraging for geogenic nutrients. This study examines the extent to which OM recycling provides nutrients to vegetation growing in soils with diverse weathering states. We thus address the fundamental problem of how forest vegetation obtains sufficient nutrition to support productivity despite wide variation in soils' nutrient contents. We hypothesized that vegetation growing on highly weathered soils relies on nutrients released from OM decay to a greater extent than vegetation growing on less weathered, more nutrient-rich substrates. For four mineralogically diverse Critical Zone Observatories (CZO) and Critical Zone Exploratory Network sites, we calculated weathering indices and approximated vegetation nutrient demand and nutrient release from OM decay. We also measured nutrient release rates from OM decay at each site. We then assessed the relationship between degree of soil weathering and the estimated fraction of nutrient demand satisfied by OM derived nutrients. Results are consistent with our hypothesis. The chemical index of alteration (CIA), a weathering index that increases in value with mineral depletion, varies predictably from 90 at the highly weathered Calhoun CZO to 60 at the Catalina CZO, where soils are more recently developed. Estimates of rates of K release from OM decay increase with CIA values. The highest release rate is 2.4 gK m-2 y-1 at Calhoun, accounting for 30% of annual vegetation K uptake; at Catalina, less than 0.5 gm-2 y-1 K is released, meeting 14% of vegetation demand. CIA also co-varies with rooting depth across sites: the deepest roots at the Calhoun sites are growing in soils with the highest CIA values, while the deepest roots at Catalina sites are growing in soils

Yield Gap, Indigenous Nutrient Supply and Nutrient Use Efficiency for Maize in China

Science.gov (United States)

Xu, Xinpeng; Liu, Xiaoyan; He, Ping; Johnston, Adrian M.; Zhao, Shicheng; Qiu, Shaojun; Zhou, Wei

2015-01-01

Great achievements have been attained in agricultural production of China, while there are still many difficulties and challenges ahead that call for put more efforts to overcome to guarantee food security and protect environment simultaneously. Analyzing yield gap and nutrient use efficiency will help develop and inform agricultural policies and strategies to increase grain yield. On-farm datasets from 2001 to 2012 with 1,971 field experiments for maize (Zea mays L.) were collected in four maize agro-ecological regions of China, and the optimal management (OPT), farmers’ practice (FP), a series of nutrient omission treatments were used to analyze yield gap, nutrient use efficiency and indigenous nutrient supply by adopting meta-analysis and ANOVA analysis. Across all sites, the average yield gap between OPT and FP was 0.7 t ha-1, the yield response to nitrogen (N), phosphorus (P), and potassium (K) were 1.8, 1.0, and 1.2 t ha-1, respectively. The soil indigenous nutrient supply of N, P, and K averaged 139.9, 33.7, and 127.5 kg ha-1, respectively. As compared to FP, the average recovery efficiency (RE) of N, P, and K with OPT increased by percentage point of 12.2, 5.5, and 6.5, respectively. This study indicated that there would be considerable potential to further improve yield and nutrient use efficiency in China, and will help develop and inform agricultural policies and strategies, while some management measures such as soil, plant and nutrient are necessary and integrate with advanced knowledge and technologies. PMID:26484543

Yield Gap, Indigenous Nutrient Supply and Nutrient Use Efficiency for Maize in China.

Directory of Open Access Journals (Sweden)

Xinpeng Xu

Full Text Available Great achievements have been attained in agricultural production of China, while there are still many difficulties and challenges ahead that call for put more efforts to overcome to guarantee food security and protect environment simultaneously. Analyzing yield gap and nutrient use efficiency will help develop and inform agricultural policies and strategies to increase grain yield. On-farm datasets from 2001 to 2012 with 1,971 field experiments for maize (Zea mays L. were collected in four maize agro-ecological regions of China, and the optimal management (OPT, farmers' practice (FP, a series of nutrient omission treatments were used to analyze yield gap, nutrient use efficiency and indigenous nutrient supply by adopting meta-analysis and ANOVA analysis. Across all sites, the average yield gap between OPT and FP was 0.7 t ha-1, the yield response to nitrogen (N, phosphorus (P, and potassium (K were 1.8, 1.0, and 1.2 t ha-1, respectively. The soil indigenous nutrient supply of N, P, and K averaged 139.9, 33.7, and 127.5 kg ha-1, respectively. As compared to FP, the average recovery efficiency (RE of N, P, and K with OPT increased by percentage point of 12.2, 5.5, and 6.5, respectively. This study indicated that there would be considerable potential to further improve yield and nutrient use efficiency in China, and will help develop and inform agricultural policies and strategies, while some management measures such as soil, plant and nutrient are necessary and integrate with advanced knowledge and technologies.

Yield Gap, Indigenous Nutrient Supply and Nutrient Use Efficiency for Maize in China.

Science.gov (United States)

Xu, Xinpeng; Liu, Xiaoyan; He, Ping; Johnston, Adrian M; Zhao, Shicheng; Qiu, Shaojun; Zhou, Wei

2015-01-01

Great achievements have been attained in agricultural production of China, while there are still many difficulties and challenges ahead that call for put more efforts to overcome to guarantee food security and protect environment simultaneously. Analyzing yield gap and nutrient use efficiency will help develop and inform agricultural policies and strategies to increase grain yield. On-farm datasets from 2001 to 2012 with 1,971 field experiments for maize (Zea mays L.) were collected in four maize agro-ecological regions of China, and the optimal management (OPT), farmers' practice (FP), a series of nutrient omission treatments were used to analyze yield gap, nutrient use efficiency and indigenous nutrient supply by adopting meta-analysis and ANOVA analysis. Across all sites, the average yield gap between OPT and FP was 0.7 t ha-1, the yield response to nitrogen (N), phosphorus (P), and potassium (K) were 1.8, 1.0, and 1.2 t ha-1, respectively. The soil indigenous nutrient supply of N, P, and K averaged 139.9, 33.7, and 127.5 kg ha-1, respectively. As compared to FP, the average recovery efficiency (RE) of N, P, and K with OPT increased by percentage point of 12.2, 5.5, and 6.5, respectively. This study indicated that there would be considerable potential to further improve yield and nutrient use efficiency in China, and will help develop and inform agricultural policies and strategies, while some management measures such as soil, plant and nutrient are necessary and integrate with advanced knowledge and technologies.

Recycling Behavior: A Multidimensional Approach

Science.gov (United States)

Meneses, Gonzalo Diaz; Palacio, Asuncion Beerli

2005-01-01

This work centers on the study of consumer recycling roles to examine the sociodemographic and psychographic profile of the distribution of recycling tasks and roles within the household. With this aim in mind, an empirical work was carried out, the results of which suggest that recycling behavior is multidimensional and comprises the undertaking…

Evaluation of dry solid waste recycling from municipal solid waste: case of Mashhad city, Iran.

Science.gov (United States)

Farzadkia, Mahdi; Jorfi, Sahand; Akbari, Hamideh; Ghasemi, Mehdi

2012-01-01

The recycling for recovery and reuse of material and energy resources undoubtedly provides a substantial alternative supply of raw materials and reduces the dependence on virgin feedstock. The main objective of this study was to assess the potential of dry municipal solid waste recycling in Mashhad city, Iran. Several questionnaires were prepared and distributed among various branches of the municipality, related organizations and people. The total amount of solid waste generated in Mashhad in 2008 was 594, 800  tons with per capita solid waste generation rate of 0.609  kg  person(-1) day(-1). Environmental educational programmes via mass media and direct education of civilians were implemented to publicize the advantages and necessity of recycling. The amount of recycled dry solid waste was increased from 2.42% of total dry solid waste (2588.36  ton  year(-1)) in 1999 to 7.22% (10, 165  ton  year(-1)) in 2008. The most important fractions of recycled dry solid waste in Mashhad included paper and board (51.33%), stale bread (14.59%), glass (9.73%), ferrous metals (9.73%), plastic (9.73%), polyethylene terephthalate (2.62%) and non-ferrous metals (0.97%). It can be concluded that unfortunately the potential of dry solid waste recycling in Mashhad has not been considered properly and there is a great effort to be made in order to achieve the desired conditions of recycling.

Attributes to facilitate e-waste recycling behaviour

Directory of Open Access Journals (Sweden)

Senawi Nur Hidayah

2016-01-01

Full Text Available This study aims to identify the set of attributes to facilitate electronic waste (e-waste behaviour among the community. E-waste disposal is increasing from year to year in parallel with increasing of global population. The short lifespan of electronics and poor e-waste recycling behaviour is among the main contributors to the steadily increasing of e-waste generated. Current recycling rate among the nation is lacking behind, which is only 10.5%. A questionnaire survey has been conducted among the students in Universiti Teknologi Malaysia to evaluate the current e-waste recycling practice. The results showed that majority of the respondents did not recycle their e-waste on campus. Aggressive efforts is needed to realize the country’s target of 20% recycling rate in year 2020, one of the effective paths is to minimize e-waste generation via active e-waste recycling behaviour among the community. Extensive literatures have been reviewed to classify the attributes to facilitate effective e-waste recycling among the community. Total of five attributes that identified in this study which are Convenience of E- waste Recycling Infrastruture and Services, E-waste Recycling Information, Incentives For E-waste Recycling, Reminder to Recycle E-waste And E-waste Recycling Infrastructure and Services. The set of attributes identified in this study may serve as guideline for the management in designing program to foster e-waste recycling behaviour among the community.

Recycling of used oil

International Nuclear Information System (INIS)

Vipulanandan, C.; Ghurye, G.

1992-01-01

This paper reports on used oil which is a valuable resource that should be recycled. Recycling used oil saves energy and natural resources. Used oil can be reprocessed and used as fuel in industrial burners and boilers. Unfortunately, more than 400 million gallons/year of used oil is lost through widespread dumping, partly due to lack of effective recycling procedures. Although used oil is not currently a federally listed hazardous waste, the U.S. EPA has proposed to list it as a hazardous waste, which will make recycling of used oil even more attractive. Laboratory samples, representing used oil, were used for detailed parametric studies and to determine the limitation of extending some of the current physical separation techniques such as sedimentation and centrifuging developed for oil-water and solid-liquid separation

Hydroponic potato production on nutrients derived from anaerobically-processed potato plant residues

Science.gov (United States)

Mackowiak, C. L.; Stutte, G. W.; Garland, J. L.; Finger, B. W.; Ruffe, L. M.

1997-01-01

Bioregenerative methods are being developed for recycling plant minerals from harvested inedible biomass as part of NASA's Advanced Life Support (ALS) research. Anaerobic processing produces secondary metabolites, a food source for yeast production, while providing a source of water soluble nutrients for plant growth. Since NH_4-N is the nitrogen product, processing the effluent through a nitrification reactor was used to convert this to NO_3-N, a more acceptable form for plants. Potato (Solanum tuberosum L.) cv. Norland plants were used to test the effects of anaerobically-produced effluent after processing through a yeast reactor or nitrification reactor. These treatments were compared to a mixed-N treatment (75:25, NO_3:NH_4) or a NO_3-N control, both containing only reagent-grade salts. Plant growth and tuber yields were greatest in the NO_3-N control and yeast reactor effluent treatments, which is noteworthy, considering the yeast reactor treatment had high organic loading in the nutrient solution and concomitant microbial activity.

Studies on recycled aggregates-based concrete.

Science.gov (United States)

Rakshvir, Major; Barai, Sudhirkumar V

2006-06-01

Reduced extraction of raw materials, reduced transportation cost, improved profits, reduced environmental impact and fast-depleting reserves of conventional natural aggregates has necessitated the use of recycling, in order to be able to conserve conventional natural aggregate. In this study various physical and mechanical properties of recycled concrete aggregates were examined. Recycled concrete aggregates are different from natural aggregates and concrete made from them has specific properties. The percentages of recycled concrete aggregates were varied and it was observed that properties such as compressive strength showed a decrease of up to 10% as the percentage of recycled concrete aggregates increased. Water absorption of recycled aggregates was found to be greater than natural aggregates, and this needs to be compensated during mix design.

Innovative Vacuum Distillation for Magnesium Recycling

Science.gov (United States)

Zhu, Tianbai; Li, Naiyi; Mei, Xiaoming; Yu, Alfred; Shang, Shixiang

Magnesium recycling now becomes a very important subject as magnesium consumption increases fast around the world. All commonly used magnesium die-casting alloys can be recycled and recovered to the primary metal quality. The recycled materials may be comprised of biscuits, sprues, runners, flash, overflows, dross, sludge, scrap parts, and old parts that are returned from service, An innovative magnesium recycle method, vacuum distillation, is developed and proved out to be able to recycle magnesium scraps, especially machining chips, oily magnesium, smelting sludge, dross or the mixture. With this process at a specific temperature and environment condition, magnesium in scraps can be gasified and then solidified to become crystal magnesium crown. This `recycled' magnesium crown is collected and used as the raw material of magnesium alloys. The experimental results show the vacuum distillation is a feasible and plausible method to recycle magnesium. Further, the cost analysis will be addressed in this paper.

Leaching behaviour of different scrap materials at recovery and recycling companies: full-, pilot- and lab-scale investigation.

Science.gov (United States)

Blondeel, E; Chys, M; Depuydt, V; Folens, K; Du Laing, G; Verliefde, A; Van Hulle, S W H

2014-12-01

Scrap material recovery and recycling companies are confronted with waste water that has a highly fluctuating flow rate and composition. Common pollutants, such as COD, nutrients and suspended solids, potentially toxic metals, polyaromatic hydrocarbons and poly chlorinated biphenyls can exceed the discharge limits. An analysis of the leaching behaviour of different scrap materials and scrap yard sweepings was performed at full-scale, pilot-scale and lab-scale in order to find possible preventive solutions for this waste water problem. The results of these leaching tests (with concentrations that frequently exceeded the Flemish discharge limits) showed the importance of regular sweeping campaigns at the company, leak proof or covered storage of specific scrap materials and oil/water separation on particular leachates. The particulate versus dissolved fraction was also studied for the pollutants. For example, up to 98% of the polyaromatic hydrocarbons, poly chlorinated biphenyls and some metals were in the particulate form. This confirms the (potential) applicability of sedimentation and filtration techniques for the treatment of the majority of the leachates, and as such the rainwater run-off as a whole. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nutrient requirements of Miscanthus x giganteus: Conclusions from a review of published studies

International Nuclear Information System (INIS)

Cadoux, Stéphane; Riche, Andrew B.; Yates, Nicola E.; Machet, Jean-Marie

2012-01-01

Miscanthus x giganteus is a perennial biomass crop particularly suited to substituting fossil fuel resources in bioenergy production, in order to reduce greenhouse gas (GHG) emissions. The area of miscanthus grown in the EU is likely to increase in the future. However, the exact nutrient and fertiliser requirements of the crop are still under debate, which leads to uncertainties when making global assessments of GHG reductions and economics. The aim of our study was to review and analyse published data, in order to determine a consensus view on the nutrient requirements of the crop, and to identify where further research is needed. The findings of this study highlight the nutrient requirements of miscanthus are low compared to other crops. This is due to: i) high nutrient absorption efficiency through extensive rooting, ii) high absorbed nutrient use efficiency, iii) significant nutrient cycling between the rhizome and aerial biomass, iv) nutrient recycling before harvest through leaf fall, and v) possible contribution of N fixation by bacteria. Due to the low yield in the establishment phase of the crop, it is not recommended to apply any fertiliser during the two first years after planting, unless planted on poor soils. From the third year, typically 4.9, 0.45 and 7.0, grams per kilogram of dry matter, of N, P and K respectively are removed at harvest, and this should be a maximum to be replaced by fertilisers. Uncertainties in the exact requirements are due i) to a lack of data, in the different studies, on the nitrogen provided by soils, ii) to a lack of knowledge on the actual contribution of the rhizome to the plant nutrition, and iii) to the inexistence of tools for the diagnosis of the plant N status.

The Compressor Recycle System

OpenAIRE

Barstad, Bjørn Ove

2010-01-01

The compressor recycle system is the main focus of this thesis. When the mass flow through a compressor becomes too low, the compressor can plunge into surge. Surge is a term that is used for axisymmetric oscillation through a compressor and is highly unwanted. The recycle system feeds compressed gas back to the intake when the mass flow becomes too low, and thereby act as a safety system.A mathematical model of the recycle system is extended and simulated in SIMULINK. The mathematical model ...

Anaesthetics stop diverse plant organ movements, affect endocytic vesicle recycling and ROS homeostasis, and block action potentials in Venus flytraps.

Science.gov (United States)

Yokawa, K; Kagenishi, T; Pavlovic, A; Gall, S; Weiland, M; Mancuso, S; Baluška, F

2017-12-11

Anaesthesia for medical purposes was introduced in the 19th century. However, the physiological mode of anaesthetic drug actions on the nervous system remains unclear. One of the remaining questions is how these different compounds, with no structural similarities and even chemically inert elements such as the noble gas xenon, act as anaesthetic agents inducing loss of consciousness. The main goal here was to determine if anaesthetics affect the same or similar processes in plants as in animals and humans. A single-lens reflex camera was used to follow organ movements in plants before, during and after recovery from exposure to diverse anaesthetics. Confocal microscopy was used to analyse endocytic vesicle trafficking. Electrical signals were recorded using a surface AgCl electrode. Mimosa leaves, pea tendrils, Venus flytraps and sundew traps all lost both their autonomous and touch-induced movements after exposure to anaesthetics. In Venus flytrap, this was shown to be due to the loss of action potentials under diethyl ether anaesthesia. The same concentration of diethyl ether immobilized pea tendrils. Anaesthetics also impeded seed germination and chlorophyll accumulation in cress seedlings. Endocytic vesicle recycling and reactive oxygen species (ROS) balance, as observed in intact Arabidopsis root apex cells, were also affected by all anaesthetics tested. Plants are sensitive to several anaesthetics that have no structural similarities. As in animals and humans, anaesthetics used at appropriate concentrations block action potentials and immobilize organs via effects on action potentials, endocytic vesicle recycling and ROS homeostasis. Plants emerge as ideal model objects to study general questions related to anaesthesia, as well as to serve as a suitable test system for human anaesthesia. © The Authors 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

High nutrient transport and cycling potential revealed in the microbial metagenome of Australian sea lion (Neophoca cinerea faeces.

Directory of Open Access Journals (Sweden)

Trish J Lavery

Full Text Available Metagenomic analysis was used to examine the taxonomic diversity and metabolic potential of an Australian sea lion (Neophoca cinerea gut microbiome. Bacteria comprised 98% of classifiable sequences and of these matches to Firmicutes (80% were dominant, with Proteobacteria and Actinobacteria representing 8% and 2% of matches respectively. The relative proportion of Firmicutes (80% to Bacteriodetes (2% is similar to that in previous studies of obese humans and obese mice, suggesting the gut microbiome may confer a predisposition towards the excess body fat that is needed for thermoregulation within the cold oceanic habitats foraged by Australian sea lions. Core metabolic functions, including carbohydrate utilisation (14%, protein metabolism (9% and DNA metabolism (7% dominated the metagenome, but in comparison to human and fish gut microbiomes there was a significantly higher proportion of genes involved in phosphorus metabolism (2.4% and iron scavenging mechanisms (1%. When sea lions defecate at sea, the relatively high nutrient metabolism potential of bacteria in their faeces may accelerate the dissolution of nutrients from faecal particles, enhancing their persistence in the euphotic zone where they are available to stimulate marine production.

Efficient Photon Recycling and Radiation Trapping in Cesium Lead Halide Perovskite Waveguides

KAUST Repository

Dursun, Ibrahim

2018-05-26

Cesium lead halide perovskite materials have attracted considerable attention for potential applications in lasers, light emitting diodes and photodetectors. Here, we provide the experimental and theoretical evidence for photon recycling in CsPbBr3 perovskite microwires. Using two-photon excitation, we recorded photoluminescence (PL) lifetimes and emission spectra as a function of the lateral distance between PL excitation and collection positions along the microwire, with separations exceeding 100 µm. At longer separations, the PL spectrum develops a red-shifted emission peak accompanied by an appearance of well-resolved rise times in the PL kinetics. We developed quantitative modeling that accounts for bimolecular recombination and photon recycling within the microwire waveguide and is sufficient to account for the observed decay modifications. It relies on a high radiative efficiency in CsPbBr3 perovskite microwires and provides crucial information about the potential impact of photon recycling and waveguide trapping on optoelectronic properties of cesium lead halide perovskite materials.

Comparative environmental assessment of natural and recycled aggregate concrete.

Science.gov (United States)

Marinković, S; Radonjanin, V; Malešev, M; Ignjatović, I

2010-11-01

Constant and rapid increase in construction and demolition (C&D) waste generation and consumption of natural aggregate for concrete production became one of the biggest environmental problems in the construction industry. Recycling of C&D waste represents one way to convert a waste product into a resource but the environment benefits through energy consumption, emissions and fallouts reductions are not certain. The main purpose of this study is to determine the potentials of recycled aggregate concrete (concrete made with recycled concrete aggregate) for structural applications and to compare the environmental impact of the production of two types of ready-mixed concrete: natural aggregate concrete (NAC) made entirely with river aggregate and recycled aggregate concrete (RAC) made with natural fine and recycled coarse aggregate. Based on the analysis of up-to-date experimental evidence, including own tests results, it is concluded that utilization of RAC for low-to-middle strength structural concrete and non-aggressive exposure conditions is technically feasible. The Life Cycle Assessment (LCA) is performed for raw material extraction and material production part of the concrete life cycle including transport. Assessment is based on local LCI data and on typical conditions in Serbia. Results of this specific case study show that impacts of aggregate and cement production phases are slightly larger for RAC than for NAC but the total environmental impacts depend on the natural and recycled aggregates transport distances and on transport types. Limit natural aggregate transport distances above which the environmental impacts of RAC can be equal or even lower than the impacts of NAC are calculated for the specific case study. Copyright © 2010 Elsevier Ltd. All rights reserved.

MOX recycling-an industrial reality

International Nuclear Information System (INIS)

Shallo, G.D.F.

1996-01-01

Reprocessing and plutonium recycling have now attained industrial maturity in France and Europe. Specifically, mixed-oxide (MOX) fuel is fabricated and used in light water reactors (LWRs) in satisfactory operating conditions. The utilities and the fuel cycle industry experience no technical difficulties, and European recycling programs are growing steadily, from 18 reactors in operation today up to 50 expected around the year 2000, putting the system reprocessing-recycling in coherence: 25 t of plutonium will then be used each year to produce the electricity equivalence of 25 millions tons of oil. Plutonium recycling in MOX fuel in current LWRs proves to be technically safe and economically competitive and meets natural resource savings and environmental protection objectives. And recycling responds properly to the nonproliferation concerns. Such an industrial experience gives a unique reference for weapons plutonium disposition through MOX use in reactors

The biogeochemical role of baleen whales and krill in Southern Ocean nutrient cycling.

Directory of Open Access Journals (Sweden)

Lavenia Ratnarajah

Full Text Available The availability of micronutrients is a key factor that affects primary productivity in High Nutrient Low Chlorophyll (HNLC regions of the Southern Ocean. Nutrient supply is governed by a range of physical, chemical and biological processes, and there are significant feedbacks within the ecosystem. It has been suggested that baleen whales form a crucial part of biogeochemical cycling processes through the consumption of nutrient-rich krill and subsequent defecation, but data on their contribution are scarce. We analysed the concentration of iron, cadmium, manganese, cobalt, copper, zinc, phosphorus and carbon in baleen whale faeces and muscle, and krill tissue using inductively coupled plasma mass spectrometry. Metal concentrations in krill tissue were between 20 thousand and 4.8 million times higher than typical Southern Ocean HNLC seawater concentrations, while whale faecal matter was between 276 thousand and 10 million times higher. These findings suggest that krill act as a mechanism for concentrating and retaining elements in the surface layer, which are subsequently released back into the ocean, once eaten by whales, through defecation. Trace metal to carbon ratios were also higher in whale faeces compared to whale muscle indicating that whales are concentrating carbon and actively defecating trace elements. Consequently, recovery of the great whales may facilitate the recycling of nutrients via defecation, which may affect productivity in HNLC areas.

ZZ WPPR, Pu Recycling Benchmark Results

International Nuclear Information System (INIS)

Lutz, D.; Mattes, M.; Delpech, Marc; Juanola, Marc

2002-01-01

Description of program or function: The NEA NSC Working Party on Physics of Plutonium Recycling has commissioned a series of benchmarks covering: - Plutonium recycling in pressurized-water reactors; - Void reactivity effect in pressurized-water reactors; - Fast Plutonium-burner reactors: beginning of life; - Plutonium recycling in fast reactors; - Multiple recycling in advanced pressurized-water reactors. The results have been published (see references). ZZ-WPPR-1-A/B contains graphs and tables relative to the PWR Mox pin cell benchmark, representing typical fuel for plutonium recycling, one corresponding to a first cycle, the second for a fifth cycle. These computer readable files contain the complete set of results, while the printed report contains only a subset. ZZ-WPPR-2-CYC1 are the results from cycle 1 of the multiple recycling benchmarks

Challenge of material recycling at large public events

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Edjabou, Maklawe Essonanawe; Boldrin, Alessio

2017-01-01

infrastructure. Sound waste management is one of the challenges. Some preliminary results presented here, concern waste material flows at a large public event, illustrated on the example of Roskilde Festival (Denmark). Roskilde Festival is a large annual event, which attracts more than 120,000 participants......Large public events such as festivals, sports events or national celebrations tend to attract a considerable number of people. While some of the events are important sources of entertainment for the participants, such gatherings create a challenge to organize and maintain a functioning...... recycling at the festival have been implemented, our preliminary results suggest that there is currently large potential to recover additional materials for recycling and improve sustainability at large public events....

Molecular composition of recycled organic wastes, as determined by solid-state {sup 13}C NMR and elemental analyses

Energy Technology Data Exchange (ETDEWEB)

Eldridge, S.M., E-mail: simon.eldridge@dpi.nsw.gov.au [Environmental Futures Centre, School of Environment, Griffith University, Nathan, QLD 4111 (Australia); NSW Department of Primary Industries, Bruxner Highway, Wollongbar, NSW 2477 (Australia); Chen, C.R. [Environmental Futures Centre, School of Environment, Griffith University, Nathan, QLD 4111 (Australia); Xu, Z.H. [Environmental Futures Centre, School of Biomolecular and Physical Sciences, Griffith University, Nathan, QLD 4111 (Australia); Nelson, P.N. [School of Earth and Environmental Sciences, James Cook University, Cairns, QLD 4870 (Australia); Boyd, S.E. [Environmental Futures Centre, School of Biomolecular and Physical Sciences, Griffith University, Nathan, QLD 4111 (Australia); Meszaros, I. [Formerly NSW Department of Primary Industries, Richmond, NSW 2753 (Australia); Chan, K.Y. [Graduate School of Environment, Macquarie University, North Ryde, NSW 2109 (Australia); Formerly NSW Department of Primary Industries, Richmond, NSW 2753 (Australia)

2013-11-15

Highlights: • Model estimated the molecular C components well for most RO wastes. • Molecular nature of organic matter in RO wastes varied widely. • Molecular composition by NMR modelling preferable to extraction techniques. • Some model shortcomings in estimating molecular composition of biochars. • Waste molecular composition important for carbon/nutrient outcomes in soil. - Abstract: Using solid state {sup 13}C NMR data and elemental composition in a molecular mixing model, we estimated the molecular components of the organic matter in 16 recycled organic (RO) wastes representative of the major materials generated in the Sydney basin area. Close correspondence was found between the measured NMR signal intensities and those predicted by the model for all RO wastes except for poultry manure char. Molecular nature of the organic matter differed widely between the RO wastes. As a proportion of organic C, carbohydrate C ranged from 0.07 to 0.63, protein C from <0.01 to 0.66, lignin C from <0.01 to 0.31, aliphatic C from 0.09 to 0.73, carbonyl C from 0.02 to 0.23, and char C from 0 to 0.45. This method is considered preferable to techniques involving imprecise extraction methods for RO wastes. Molecular composition data has great potential as a predictor of RO waste soil carbon and nutrient outcomes.

Recycle and reuse of materials and components from waste streams of nuclear fuel cycle facilities

International Nuclear Information System (INIS)

2000-01-01

All nuclear fuel cycle processes utilize a wide range of equipment and materials to produce the final products they are designed for. However, as at any other industrial facility, during operation of the nuclear fuel cycle facilities, apart from the main products some byproducts, spent materials and waste are generated. A lot of these materials, byproducts or some components of waste have a potential value and may be recycled within the original process or reused outside either directly or after appropriate treatment. The issue of recycle and reuse of valuable material is important for all industries including the nuclear fuel cycle. The level of different materials involvement and opportunities for their recycle and reuse in nuclear industry are different at different stages of nuclear fuel cycle activity, generally increasing from the front end to the back end processes and decommissioning. Minimization of waste arisings and the practice of recycle and reuse can improve process economics and can minimize the potential environmental impact. Recognizing the importance of this subject, the International Atomic Energy Agency initiated the preparation of this report aiming to review and summarize the information on the existing recycling and reuse practice for both radioactive and non-radioactive components of waste streams at nuclear fuel cycle facilities. This report analyses the existing options, approaches and developments in recycle and reuse in nuclear industry

Environmental aspects of recycling

International Nuclear Information System (INIS)

Jansma, R.; Van Gemert, F.

2001-01-01

Advanced recycling options were studied. Emphasis was on the production of high-level waste. All other impacts, e.g. emissions, were considered to be of minor importance, since from a technical point of view they can be limited to any desired extent. An objective was to gather data from the industry and to use them in a Life Cycle Analysis (LCA) of several fuel cycle options. It was necessary to complete our data set with literature data. At the end of our project we could benefit from the results of several Expert Working Groups of OECD/NEA. Detailed information was available for the once-through fuel cycle (OFC) and the fuel cycle with mono recycling of MOX. For the other more advanced fuel cycle options information was of a more qualitative nature. The established set of data was sufficient to conduct a streamlined LCA with focus on waste production for final disposal. Some remarks should be made before comparing the various fuel cycle options studied. The first relates to plutonium that contributes to more than 90% of the radiotoxicity of the spent fuel for more than 1000 centuries. Large concern for transmutation of minor actinides will disproportional if plutonium itself is not eliminated. The second remark is that the fission products contribute potentially very little to the radiotoxicity especially when some long-lived radionuclides after separation are imprisoned in stable matrices to prevent them to be carried by underground water. From all nuclear fuel cycles considered, the MIX cycle in LWRs, with recycling of plutonium and minor actinides has the lowest minor actinides production (0.018 kg/TW e h) and the plutonium production is also quite low (0.06 kg/TW e h). The MIX cycle without minor actinides recycling performs a little better with respect to plutonium production (0.04 kg/TW e h) but has a relatively high minor actinides production (8.7 kg/TW e h). Another conclusion is that burning of minor actinides in fast reactors (MA 0.28 kg/TW e h, Pu 0

Frequent Questions on Recycling

Science.gov (United States)

This is a list of frequent questions on recycling, broken down into five categories. These are answers to common questions that EPA has received from press and web inquiries. This list is located on the Reduce, Reuse, Recycle website.

Carbon storage and nutrient mobilization from soil minerals by deep roots and rhizospheres

DEFF Research Database (Denmark)

Callesen, Ingeborg; Harrison, Robert; Stupak, Inge

2016-01-01

studies on potential release of nutrients due to chemical weathering indicate the importance of root access to deep soil layers. Nutrient release profiles clearly indicate depletion in the top layers and a much higher potential in B and C horizons. Reviewing potential sustainability of nutrient supplies......Roots mobilize nutrients via deep soil penetration and rhizosphere processes inducing weathering of primary minerals. These processes contribute to C transfer to soils and to tree nutrition. Assessments of these characteristics and processes of root systems are important for understanding long......-term supplies of nutrient elements essential for forest growth and resilience. Research and techniques have significantly advanced since Olof Tamm’s 1934 “base mineral index” for Swedish forest soils, and the basic nutrient budget estimates for whole-tree harvesting systems of the 1970s. Recent research...

Biological treatment: potential reusing of recycled plastics from grenhouses; La depuracin biolgica: posible reutilizacin de plsticos reciclados procedentes de invernaderos

Energy Technology Data Exchange (ETDEWEB)

Zamorano, M.; Hontaria, E. [Universidad de Granada (Spain)

1997-12-31

The purpose of this study was to investigate recycled plastic used to cover crops as support beds in submerged biofilters for the purification of residual water, which also permit the re-used of recycled or waste products and the clarification and improvement of the effluent flow from the filter. The recycled plastic shows that the efficiency was 88% COD-removal and 84% SS-removal, without secondary clarification. The functioning of the system with this material has not improved 100%, this study has opened up a new field of investigation that will perfect the system and materials. (Author) 10 refs.

Recycled concrete with coarse recycled aggregate. An overview and analysis

Directory of Open Access Journals (Sweden)

B. González-Fonteboa

2018-04-01

Full Text Available The construction field has contributed to environmental degradation, producing a high amount of construction and demolition waste (C&D waste and consuming large volumes of natural resources. In this context, recycled concrete (RC has been recognised as a means to preserve natural resources and reduce space for waste storage. During the last decades, many researchers have developed works studying different recycled concrete properties. This review focuses on structural RC made with coarse recycled aggregate from concrete waste. The main objective is to provide a state of the art report on RC’s properties and an analysis on how to predict them taking into account relevant research works. Moreover, the study tries to collect and update RC findings, proposing equations to define RC’s performance, in terms of mechanical strength, modulus of elasticity, stress-strain, creep and shrinkage.

Diversity and community structure of cyanobacteria and other microbes in recycling irrigation reservoirs.

Science.gov (United States)

Kong, Ping; Richardson, Patricia; Hong, Chuanxue

2017-01-01

Recycling irrigation reservoirs (RIRs) are emerging aquatic environments of global significance to crop production, water conservation and environmental sustainability. This study characterized the diversity and population structure of cyanobacteria and other detected microbes in water samples from eight RIRs and one adjacent runoff-free stream at three ornamental crop nurseries in eastern (VA1 and VA3) and central (VA2) Virginia after cloning and sequencing the 16S rRNA gene targeting cyanobacteria and chloroplast of eukaryotic phytoplankton. VA1 and VA2 utilize a multi-reservoir recycling irrigation system with runoff channeled to a sedimentation reservoir which then overflows into transition and retention reservoirs where water was pumped for irrigation. VA3 has a single sedimentation reservoir which was also used for irrigation. A total of 208 operational taxonomic units (OTU) were identified from clone libraries of the water samples. Among them, 53 OTUs (358 clones) were cyanobacteria comprising at least 12 genera dominated by Synechococcus species; 59 OTUs (387 clones) were eukaryotic phytoplankton including green algae and diatoms; and 96 were other bacteria (111 clones). Overall, cyanobacteria were dominant in sedimentation reservoirs, while eukaryotic phytoplankton and other bacteria were dominant in transition/retention reservoirs and the stream, respectively. These results are direct evidence demonstrating the negative impact of nutrient-rich horticultural runoff, if not contained, on natural water resources. They also help in understanding the dynamics of water quality in RIRs and have practical implications. Although both single- and multi-reservoir recycling irrigation systems reduce the environmental footprint of horticultural production, the former is expected to have more cyanobacterial blooming, and consequently water quality issues, than the latter. Thus, a multi-reservoir recycling irrigation system should be preferred where feasible.

Influence of harvest managements on biomass nutrient concentrations and removal rates of festulolium and tall fescue from a poorly drained nutrient-rich fen peatland

DEFF Research Database (Denmark)

Kandel, Tanka; Elsgaard, Lars; Lærke, Poul Erik

2017-01-01

This study was designed to show the effects of harvest time and frequency on biomass nutrient concentrations (total ash, N, P, K, Ca, Mg, Fe, Mn, Cu and Zn) as well as total nutrient removal potential by festulolium and tall fescue cultivated on a nutrient-rich fen peatland. The harvest managemen...

Radiological control criteria for materials considered for recycle and reuse

International Nuclear Information System (INIS)

Kennedy, W.E. Jr.; Hill, R.L.; Aaberg, R.L.; Wallo, A. III

1994-11-01

Pacific Northwest Laboratory (PNL) is conducting technical analyses to support the US Department of Energy (DOE), Office of Environmental Guidance, Air, Water, and Radiation Division (DOE/EH-232) in developing radiological control criteria for recycling or reuse of metals or equipment containing residual radioactive contamination from DOE operations. The criteria, framed as acceptable concentrations for release of materials for recycling or reuse, are risk-based and were developed through analysis of generic radiation exposure scenarios and pathways. The analysis includes evaluation of relevant radionuclides, potential mechanisms of exposure, and non-health-related impacts of residual radioactivity on electronics and film. The analysis considers 42 key radionuclides that DOE operations are known to generate and that may be contained in recycled or reused metals or equipment. Preliminary results are compared with similar results reported by the International Atomic Energy Agency, by radionuclide grouping

Solid waste recycling in Rajshahi city of Bangladesh.

Science.gov (United States)

Bari, Q Hamidul; Hassan, K Mahbub; Haque, M Ehsanul

2012-11-01

Efficient recycling of solid wastes is now a global concern for a sustainable and environmentally sound management. In this study, traditional recycling pattern of solid waste was investigated in Rajshahi municipality which is the fourth largest city of Bangladesh. A questionnaire survey had been carried out in various recycle shops during April 2010 to January 2011. There were 140 recycle shops and most of them were located in the vicinity of Stadium market in Rajshahi. About 1906 people were found to be involved in recycling activities of the city. The major fraction of recycled wastes were sent to capital city Dhaka for further manufacture of different new products. Only a small amount of wastes, specially plastics, were processed in local recycle factories to produce small washing pots and bottle caps. Everyday, an estimated 28.13 tons of recycled solid wastes were handled in Rajshahi city area. This recycled portion accounted for 8.25% of the daily total generated wastes (341 ton d(-1)), 54.6% of total recyclable wastes (51.49 ton d(-1)) and 68.29% of readily recyclable wastes (41.19 ton d(-1)). Major recycled materials were found to be iron, glass, plastic, and papers. Only five factories were involved in preliminary processing of recyclable wastes. Collecting and processing secondary materials, manufacturing recycled-content products, and then buying recycled products created a circle or loop that ensured the overall success of recycling and generated a host of financial, environmental, and social returns. Copyright © 2012 Elsevier Ltd. All rights reserved.

Interactions between biomass energy technologies and nutrient and carbon balances at the farm level

Energy Technology Data Exchange (ETDEWEB)

Joergensen, Uffe; Molt Petersen, B. [Danish Inst. of Agricultural Science, Dept. of Agroecology, Tjele (Denmark)

2006-08-15

Biomass energy is by far the largest renewable energy source in the world (IEA Renewable information (www.iea.org)). Biomass utilisation is closely linked to management and sustainability issues of forestry and agriculture. Carbon is extracted from forests and agriculture to bioenergy facilities, from where it is partly or fully emitted as CO{sub 2} and thus no longer available for sustaining soil organic matter content. Nutrients are extracted as well and, depending of the conversion technology, they may be recycled to farmland or lost as gaseous emissions. Thus, we must be able to describe these effects, and to suggest strategies to alleviate adverse effects on farm sustainability and on the environment. By choosing intelligent combinations of cropping systems and energy conversion technologies, win-win solutions may be achieved. This paper illustrates, via three cases, some agricultural impacts of choice of biomass technology and describes an intriguing possibility for recycling municipal or industrial wastes through the bioenergy chain. (au)

Bioenergy, material, and nutrients recovery from household waste: Advanced material, substance, energy, and cost flow analysis of a waste refinery process

International Nuclear Information System (INIS)

Tonini, Davide; Dorini, Gianluca; Astrup, Thomas Fruergaard

2014-01-01

Highlights: • We modeled material, substance, energy, and cost flows of a waste refinery process. • Ca. 56% of 1 Mg dry waste input can be recovered as bioliquid yielding 6.2 GJ biogas. • Nutrients and carbon recovery in the bioliquid was estimated to 81–89%. • The biogenic carbon in the input waste was 63% of total carbon based on 14 C analyses. • The quality of the digestate may be critical with respect to use on land. - Abstract: Energy, materials, and resource recovery from mixed household waste may contribute to reductions in fossil fuel and resource consumption. For this purpose, legislation has been enforced to promote energy recovery and recycling. Potential solutions for separating biogenic and recyclable materials are offered by waste refineries where a bioliquid is produced from enzymatic treatment of mixed waste. In this study, potential flows of materials, energy, and substances within a waste refinery were investigated by combining sampling, analyses, and modeling. Existing material, substance, and energy flow analysis was further advanced by development of a mathematical optimization model for determination of the theoretical recovery potential. The results highlighted that the waste refinery may recover ca. 56% of the dry matter input as bioliquid, yielding 6.2 GJ biogas-energy. The potential for nitrogen, phosphorous, potassium, and biogenic carbon recovery was estimated to be between 81% and 89% of the input. Biogenic and fossil carbon in the mixed household waste input was determined to 63% and 37% of total carbon based on 14 C analyses. Additional recovery of metals and plastic was possible based on further process optimization. A challenge for the process may be digestate quality, as digestate may represent an emission pathway when applied on land. Considering the potential variability of local revenues for energy outputs, the costs for the waste refinery solution appeared comparable with alternatives such as direct incineration

Carambola optics for recycling of light.

Science.gov (United States)

Leutz, Ralf; Fu, Ling; Ries, Harald

2006-04-20

Recycling of light allows the luminance (radiance) emitted by a light source to be increased at the cost of reducing the total luminous flux (radiant power). Recycling of light means returning part of the emitted light to the source, where part of it will escape absorption. An optical design that is suitable for multiple and controlled recycling is described. Carambola optics is named for its resemblance to star fruit. Several pairs of mirrors or prisms redirect light repeatedly onto the source, thus achieving multiple transits of the light through the source. This recycled light exits the carambola in the same phase space as light directly emitted and not recycled.

Text recycling: acceptable or misconduct?

Science.gov (United States)

Harriman, Stephanie; Patel, Jigisha

2014-08-16

Text recycling, also referred to as self-plagiarism, is the reproduction of an author's own text from a previous publication in a new publication. Opinions on the acceptability of this practice vary, with some viewing it as acceptable and efficient, and others as misleading and unacceptable. In light of the lack of consensus, journal editors often have difficulty deciding how to act upon the discovery of text recycling. In response to these difficulties, we have created a set of guidelines for journal editors on how to deal with text recycling. In this editorial, we discuss some of the challenges of developing these guidelines, and how authors can avoid undisclosed text recycling.

Heavy metal removal by GLDA washing: Optimization, redistribution, recycling, and changes in soil fertility.

Science.gov (United States)

Wang, Guiyin; Zhang, Shirong; Xu, Xiaoxun; Zhong, Qinmei; Zhang, Chuer; Jia, Yongxia; Li, Ting; Deng, Ouping; Li, Yun

2016-11-01

Soil washing, an emerging method for treating soils contaminated by heavy metals, requires an evaluation of its efficiency in simultaneously removing different metals, the quality of the soil following remediation, and the reusability of the recycled washing agent. In this study, we employed N,N-bis (carboxymethyl)-l-glutamic acid (GLDA), a novel and readily biodegradable chelator to remove Cd, Pb, and Zn from polluted soils. We investigated the influence of washing conditions, including GLDA concentration, pH, and contact time on their removal efficiencies. The single factor experiments showed that Cd, Pb, and Zn removal efficiencies reached 70.62, 74.45, and 34.43% in mine soil at a GLDA concentration of 75mM, a pH of 4.0, and a contact time of 60min, and in polluted farmland soil, removal efficiencies were 69.12, 78.30, and 39.50%, respectively. We then employed response surface methodology to optimize the washing parameters. The optimization process showed that the removal efficiencies were 69.50, 88.09, and 40.45% in mine soil and 71.34, 81.02, and 50.95% in polluted farmland soil for Cd, Pb, and Zn, respectively. Moreover, the overall highly effective removal of Cd and Pb was connected mainly to their highly effective removal from the water-soluble, exchangeable, and carbonate fractions. GLDA-washing eliminated the same amount of metals as EDTA-washing, while simultaneously retaining most of the soil nutrients. Removal efficiencies of recycled GLDA were no >5% lower than those of the fresh GLDA. Therefore, GLDA could potentially be used for the rehabilitation of soil contaminated by heavy metals. Copyright © 2016 Elsevier B.V. All rights reserved.

Improving the layout of recycling centres by use of lean production principles.

Science.gov (United States)

Sundin, Erik; Björkman, Mats; Eklund, Mats; Eklund, Jörgen; Engkvist, Inga-Lill

2011-06-01

There has been increased focus on recycling in Sweden during recent years. This focus can be attributed to external environmental factors such as tougher legislation, but also to the potential gains for raw materials suppliers. Recycling centres are important components in the Swedish total recycling system. Recycling centres are manned facilities for waste collection where visitors can bring, sort and discard worn products as well as large-sized, hazardous, and electrical waste. The aim of this paper was to identify and describe the main flows and layout types at Swedish recycling centres. The aim was also to adapt and apply production theory for designing and managing recycling centre operations. More specifically, this means using lean production principles to help develop guidelines for recycling centre design and efficient control. Empirical data for this research was primarily collected through interviews and questionnaires among both visitors and employees at 16 Swedish recycling centres. Furthermore, adapted observation protocols have been used in order to explore visitor activities. There was also close collaboration with a local recycling centre company, which shared their layout experiences with the researchers in this project. The recycling centres studied had a variety of problems such as queues of visitors, overloading of material and improper sorting. The study shows that in order to decrease the problems, the recycling centres should be designed and managed according to lean production principles, i.e. through choosing more suitable layout choices with visible and linear flows, providing better visitor information, and providing suitable technical equipment. Improvements can be achieved through proper planning of the layout and control of the flow of vehicles, with the result of increased efficiency and capacity, shorter visits, and cleaner waste fractions. The benefits of a lean production mindset include increased visitor capacity, waste

Structural recycled concrete: utilization of recycled aggregate from construction and demolition wastes

International Nuclear Information System (INIS)

Alaejos Gutierrez, P.; Sanchez de Juan, M.

2015-01-01

This paper aims to present the main results of CEDEX research works concerning the use of recycled aggregates for structural concretes. By way of conclusion, recommendations on the requirements of the recycled aggregates have been established, providing information about the influence of these aggregates on the properties of structural concrete. (Author)

Development and Validation of an Instrument for Assessing Attitudes of High School Students about Recycling

Science.gov (United States)

Ugulu, Ilker

2015-01-01

Recycling and its applications are growing significantly due to the great potential for solving a range of environmental problems in society. Nevertheless, there are currently very few instruments that can provide valid and reliable data on students' attitudes toward recycling. In this regard, this article focuses on the development and validation…

Plastics recycling: challenges and opportunities.

Science.gov (United States)

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-07-27

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

Plastics recycling: challenges and opportunities

Science.gov (United States)

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-01-01

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

Recycling in the 90's - a shared responsibility

International Nuclear Information System (INIS)

Anon.

1993-01-01

Recycling means different things to different people. To consumers, recycling can mean putting out bottles and cans for curbside collection. To a product maker - a manufacturer of raw materials, fabricator of goods or products, or brand owner - recycling can mean reformulating goods to include recycled materials. To recycling service providers, recycling can mean providing cost-efficient collection services. To public policy makers in all levels of government recycling can mean establishing collection and utilization regulations. For recycling to work successfully, these diverse groups must work together and share responsibility for its success. Also, if recycling is to succeed on a large scale and over the long term, three critical points must be first addressed: These points are: approach, economics, and markets. These points are discussed

Properties of concrete blocks prepared with low grade recycled aggregates.

Science.gov (United States)

Poon, Chi-Sun; Kou, Shi-cong; Wan, Hui-wen; Etxeberria, Miren

2009-08-01

Low grade recycled aggregates obtained from a construction waste sorting facility were tested to assess the feasibility of using these in the production of concrete blocks. The characteristics of the sorted construction waste are significantly different from that of crushed concrete rubbles that are mostly derived from demolition waste streams. This is due to the presence of higher percentages of non-concrete components (e.g. >10% soil, brick, tiles etc.) in the sorted construction waste. In the study reported in this paper, three series of concrete block mixtures were prepared by using the low grade recycled aggregates to replace (i) natural coarse granite (10mm), and (ii) 0, 25, 50, 75 and 100% replacement levels of crushed stone fine (crushed natural granite concrete blocks. Test results on properties such as density, compressive strength, transverse strength and drying shrinkage as well as strength reduction after exposure to 800 degrees C are presented below. The results show that the soil content in the recycled fine aggregate was an important factor in affecting the properties of the blocks produced and the mechanical strength deceased with increasing low grade recycled fine aggregate content. But the higher soil content in the recycled aggregates reduced the reduction of compressive strength of the blocks after exposure to high temperature due probably to the formation of a new crystalline phase. The results show that the low grade recycled aggregates obtained from the construction waste sorting facility has potential to be used as aggregates for making non-structural pre-cast concrete blocks.

Life cycle assessment of a road safety product made with virgin and recycled HDPE.

Science.gov (United States)

Simões, Carla L; Xará, Susana M; Bernardo, C A

2011-04-01

The present study aims at evaluating the potential environmental impact of using recycled high-density polyethylene (HDPE) in the production of an anti-glare lamella (AGL), a road safety device currently manufactured from virgin (not recycled) polymer. The impact was evaluated using the life cycle assessment (LCA) technique and comparing two alternative systems: current AGL, manufactured from virgin HDPE, and optional AGL, made with recycled HDPE obtained from post-consumer packages. The AGL manufacturing phase was found to be responsible for most of the impacts in both systems, with the production of the raw material being the largest contributor for that phase. The present study makes a contribution to the problem of developing value-added products made from post-consumer polymeric recyclates.

Compressive strength improvement for recycled concrete aggregate

Directory of Open Access Journals (Sweden)

Mohammed Dhiyaa

2018-01-01

Full Text Available Increasing amount of construction waste and, concrete remnants, in particular pose a serious problem. Concrete waste exist in large amounts, do not decay and need long time for disintegration. Therefore, in this work old demolished concrete is crashed and recycled to produce recycled concrete aggregate which can be reused in new concrete production. The effect of using recycled aggregate on concrete compressive strength has been experimentally investigated; silica fume admixture also is used to improve recycled concrete aggregate compressive strength. The main parameters in this study are recycled aggregate and silica fume admixture. The percent of recycled aggregate ranged from (0-100 %. While the silica fume ranged from (0-10 %. The experimental results show that the average concrete compressive strength decreases from 30.85 MPa to 17.58 MPa when the recycled aggregate percentage increased from 0% to 100%. While, when silica fume is used the concrete compressive strength increase again to 29.2 MPa for samples with 100% of recycled aggregate.