WorldWideScience

Sample records for biological nutrient removal

  1. Biological Nutrient Removal in Compact Biofilm Systems

    NARCIS (Netherlands)

    Bassin, J.P.

    2012-01-01

    The removal of nutrients such as nitrogen and phosphorus from both domestic and industrial wastewaters is imperative since they potentially harm the environment. One of the main consequences of excessive availability of nitrogen and phosphorus in aquatic ecosystems (freshwater, marine and estuarine)

  2. Biological Nutrient Removal in Compact Biofilm Systems

    OpenAIRE

    Bassin, J.P.

    2012-01-01

    The removal of nutrients such as nitrogen and phosphorus from both domestic and industrial wastewaters is imperative since they potentially harm the environment. One of the main consequences of excessive availability of nitrogen and phosphorus in aquatic ecosystems (freshwater, marine and estuarine) is the overgrowth of algae and other aquatic plants, a phenomenon designated as eutrophication. Algae and aquatic plants induce depletion of oxygen in water basins, resulting in massive death of e...

  3. Benchmarking Biological Nutrient Removal in Wastewater Treatment Plants

    DEFF Research Database (Denmark)

    Flores-Alsina, Xavier; Gernaey, Krist; Jeppsson, Ulf

    2011-01-01

    This paper examines the effect of different model assumptions when describing biological nutrient removal (BNR) by the activated sludge models (ASM) 1, 2d & 3. The performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) benchmark wastewater treatment plant...

  4. Nutrient release, recovery and removal from waste sludge of a biological nutrient removal system.

    Science.gov (United States)

    Wang, Yi; Zheng, Shu-Jian; Pei, Li-Ying; Ke, Li; Peng, Dang-Cong; Xia, Si-Qing

    2014-01-01

    The uncontrolled release of nutrients from waste sludge results in nitrogen and phosphorus overloading in wastewater treatment plants when supernatant is returned to the inlet. A controlled release, recovery and removal of nutrient from the waste sludge of a Biological Nutrient Removal system (BNR) are investigated. Results showed that the supernatant was of high mineral salt, high electrical conductivity and poor biodegradability, in addition to high nitrogen and phosphorus concentrations after the waste sludge was hydrolysed through sodium dodecyl sulphate addition. Subsequently, over 91.8% of phosphorus and 10.5% of nitrogen in the supernatants were extracted by the crystallization method under the conditions of 9.5 pH and 400 rpm. The precipitate was mainly struvite according to X-ray diffraction and morphological examination. A multistage anoxic-oxic Moving Bed Biofilm Reactor (MBBR) was then adopted to remove the residual carbon, nitrogen and phosphorus in the supernatant. The MBBR exhibited good performance in simultaneously removing carbon, nitrogen and phosphorus under a short aeration time, which accounted for 31.25% of a cycle. Fluorescence in situ hybridization analysis demonstrated that nitrifiers presented mainly in floc, although higher extracellular polymeric substance content, especially DNA, appeared in the biofilm. Thus, a combination of hydrolysis and precipitation, followed by the MBBR, can complete the nutrient release from the waste sludge of a BNR system, recovers nutrients from the hydrolysed liquor and removes nutrients from leftovers effectively. PMID:25176308

  5. Investigation of bacterial populations in a biological nutrient removal system

    OpenAIRE

    Kavanaugh, Rathi G.

    1991-01-01

    Bacterial populations proliferating in a pilot scale biological nutrient removal system (BNR) were studied. The objective of the research was to develop media and methods to identify bacterial populations in BNR systems. Samples were obtained from the last aerobic zone of a University of Cape Town (UCT)-type system. The most probable numbers (MPN) of bacteria in the samples were analyzed in liquid media containing volatile fatty acids as sole sources of carbon. Samples...

  6. Effects of Sludge Retention Times on Nutrient Removal and Nitrous Oxide Emission in Biological Nutrient Removal Processes

    OpenAIRE

    Bo Li; Guangxue Wu

    2014-01-01

    Sludge retention time (SRT) is an important factor affecting not only the performance of the nutrient removal and sludge characteristics, but also the production of secondary pollutants such as nitrous oxide (N2O) in biological nutrient removal (BNR) processes. Four laboratory-scale sequencing batch reactors (SBRs), namely, SBR5, SBR10, SBR20 and SBR40 with the SRT of 5 d, 10 d, 20 d and 40 d, respectively, were operated to examine effects of SRT on nutrient removal, activated sludge characte...

  7. Operation and control of SBR processes for enhanced biological nutrient removal from wastewater

    OpenAIRE

    Puig Broch, Sebastià

    2008-01-01

    In the last decades, the awareness of environmental issues has increased in society considerably. There is an increasing need to improve the effluent quality of domestic wastewater treatment processes. This thesis describes the application of the Sequencing Batch Reactor (SBR) technology for Biological Nutrient Removal (BNR) from the wastewater. In particular, the work presented evolves from the nitrogen removal to the biological nutrient removal (i.e. nitrogen plus phosphorous removal) with ...

  8. Circulating fluidized bed biological reactor for nutrients removal

    Institute of Scientific and Technical Information of China (English)

    Yubo CUI; Hongbo LIU; Chunxue BAI

    2008-01-01

    A new biological nitrogen removal process, which is named herein "The circulating fluidized bed bio-reactor (CFBBR)", was developed for simultaneous removal of nitrogen and organic matter. This process was composed of an anaerobic bed (Riser), aerobic bed (Downer) and connecting device. Influent and nitrified liquid from the aerobic bed enters the anaerobic bed from the bottom of the anaerobic bed, completing the removal of nitrogen and organic matter. The system performance under the conditions of different inflow loadings and nitrified liquid recirculation rates ranging from 200% to 600% was examined. From a technical and economic point of view, the optimum nitrified liquid recirculation rate was 400%. With a shortest total retention time of 2.5 h (0.8 h in the anaerobic bed and 1.5 h in the aerobic bed) and a nitrified liquid recir-culation rate of 400% based on the intluent flow rate, the average removal efficiencies of total nitrogen (TN) and sol-uble chemical oxygen demand (SCOD) were found to be 88% and 95%, respectively. The average effluent concentra-tions of TN and SCOD were 3.5 mg/L and 16 mg/L, respectively. The volatile suspended solid (VSS) concentra-tion, nitrification rate and denitrification rate in the system were less than 1.0 g/L, 0.026-0.1 g NH4+-N/g VSS.d, and 0.016-0.074 g NOx--N/g VSS.d, respectively.

  9. Economic Benefits of Advanced Control Strategies in Biological Nutrient Removal Systems

    DEFF Research Database (Denmark)

    Carstensen, J.; Nielsen, M.K.; Harremoës, Poul

    1994-01-01

    Advances in on-line monitoring of nutrient salt concentrations and computer technology has created a large potential for the implementation of advanced and complex control strategies in biological nutrient removal systems. The majority of wastewater treatment plants today are operated with very...

  10. Effects of Sludge Retention Times on Nutrient Removal and Nitrous Oxide Emission in Biological Nutrient Removal Processes

    Directory of Open Access Journals (Sweden)

    Bo Li

    2014-03-01

    Full Text Available Sludge retention time (SRT is an important factor affecting not only the performance of the nutrient removal and sludge characteristics, but also the production of secondary pollutants such as nitrous oxide (N2O in biological nutrient removal (BNR processes. Four laboratory-scale sequencing batch reactors (SBRs, namely, SBR5, SBR10, SBR20 and SBR40 with the SRT of 5 d, 10 d, 20 d and 40 d, respectively, were operated to examine effects of SRT on nutrient removal, activated sludge characteristics and N2O emissions. The removal of chemical oxygen demand or total phosphorus was similar under SRTs of 5–40 d, SRT mainly affected the nitrogen removal and the optimal SRT for BNR was 20 d. The molecular weight distribution of the effluent organic matters was in the range of 500–3,000 Da under SRTs of 5–40 d. The lowest concentration of the effluent soluble microbial products concentration was obtained at the SRT of 5 d. Nitrifier growth was limited at a short SRT and nitrite existed in the effluent of SBR5. With increasing SRTs, mixed liquor suspended solids concentration increased while the excess sludge production was reduced due to the high endogenous decay rate at high SRTs. Endogenous decay coefficients were 0.020 d−1, 0.036 d−1, 0.037 d−1 and 0.039 d−1 under SRTs of 5–40 d, respectively. In BNR, the N2O emission occurred mainly during the aerobic phase and its emission ratio decreased with increasing SRTs. The ratio between the N2O-N emission and the removed ammonium nitrogen in the aerobic phase was 5%, 3%, 1.8% and 0.8% at the SRT of 5 d, 10 d, 20 d and 40 d, respectively. With low concentrations of dissolved oxygen and high concentrations of oxidized nitrogen, the N2O emission was significantly accelerated due to heterotrophic denitrification activities.

  11. Enhanced Biological Phosphorus Removal from Dairy Manure to Meet Nitrogen:Phosphorus Crop Nutrient Requirements

    OpenAIRE

    Yanosek, Kristina Anne

    2002-01-01

    Over the last two decades, livestock operations have become highly concentrated due to growing trends towards larger, more confined facilities and a decrease in cropland on smaller farms. This has led to greater amounts of excess manure nutrients on farms, increasing the potential for nutrient pollution of water bodies from runoff. The purpose of this study was to determine if enhanced biological phosphorus removal (EBPR) is a viable alternative for managing excess manure nutrients on dairy...

  12. Benchmarking Biological Nutrient Removal in Wastewater Treatment Plants:Influence of Mathematical Model Assumptions

    OpenAIRE

    Flores-Alsina, Xavier; Gernaey, Krist; Jeppsson, Ulf

    2011-01-01

    This paper examines the effect of different model assumptions when describing biological nutrient removal (BNR) by the activated sludge models (ASM) 1, 2d & 3. The performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) benchmark wastewater treatment plant was compared for a series of model assumptions. Three different model approaches describing BNR are considered. In the reference case, the original model implementations are used to simulate WWTP...

  13. Biological nutrient removal in a sequencing batch reactor operated as oxic/anoxic/extended-idle regime.

    Science.gov (United States)

    Li, Xiao-ming; Chen, Hong-bo; Yang, Qi; Wang, Dong-bo; Luo, Kun; Zeng, Guang-ming

    2014-06-01

    Previous researches have demonstrated that biological phosphorus removal from wastewater could be induced by oxic/extended-idle (O/EI) regime. In this study, an anoxic period was introduced after the aeration to realize biological nutrient removal. High nitrite accumulation ratio and polyhydroxyalkanoates biosynthesis were obtained in the aeration and biological nutrient removal could be well achieved in oxic/anoxic/extended-idle (O/A/EI) regime for the wastewater used. In addition, nitrogen and phosphorus removal performance in O/A/EI regime was compared with that in conventional anaerobic/anoxic/aerobic (A(2)/O) and O/EI processes. The results showed that O/A/EI regime exhibited higher nitrogen and phosphorus removal than A(2)/O and O/EI processes. More ammonium oxidizing bacteria and polyphosphate accumulating organisms and less glycogen accumulating organisms containing in the biomass might be the principal reason for the better nitrogen and phosphorus removal in O/A/EI regime. Furthermore, biological nutrient removal with O/A/EI regime was demonstrated with municipal wastewater. The average TN, SOP and COD removal efficiencies were 93%, 95% and 87%, respectively. PMID:24393562

  14. Assessment of the removal of estrogenicity in biological nutrient removal wastewater treatment processes

    International Nuclear Information System (INIS)

    The removal of estrogenicity in a University of Cape Town-biological nutrient removal (UCT-BNR) wastewater treatment process was investigated using pilot and bench scale systems, batch experiments and mathematical modeling. In the pilot BNR process, 96 ± 5% of the estrogenicity exerted by the influent wastewater was removed by the treatment process. The degradation efficiencies in the anaerobic, anoxic and aerobic zones of the pilot BNR bioreactor were 11 ± 9%, 18 ± 2% and 93 ± 10%, respectively. In order to further understand the performance of the BNR process in the removal of estrogenicity from wastewater, a bench scale BNR process was operated with synthetic wastewater dosed with E1 and E2. The removal of estrogenicity in the bench scale system (95 ± 5%) was comparable to the pilot BNR process and the degradation efficiencies were estimated to be 8 ± 0.8%, 38 ± 4% and 85 ± 22% in the anaerobic, anoxic and aerobic zones, respectively. A biotransformation model developed to predict the fate of E1 and E2 in batch tests using the sludge from the BNR process was calibrated using the data from the experiments. The biotransformation rate constants for the transformation of E2 to E1 were estimated as 71 ± 1.5, 31 ± 3.3 and 1 ± 0.9 L g COD−1 d−1 for the aerobic, anoxic and anaerobic batch tests, respectively, while the corresponding biotransformation rate constants for the transformation of E1 were estimated to be 7.3 ± 1.0, 3 ± 2.0, and 0.85 ± 0.6 L·g COD−1 d−1. A steady state mass balance model formulated to describe the interactions between E2 and E1 in BNR activated sludge reasonably described the fate of E1 and E2 in the BNR process. - Highlights: • Comparable estrogenicity removal was observed from two BNR processes. • Pseudo first order model described the transformation of E2 and E1 in BNR process. • Biotransformation of E1 in BNR activated sludge controls the degradation of E2

  15. Assessment of the removal of estrogenicity in biological nutrient removal wastewater treatment processes

    Energy Technology Data Exchange (ETDEWEB)

    Ogunlaja, O.O., E-mail: oogunlaj@uwaterloo.ca; Parker, W.J., E-mail: wjparker@uwaterloo.ca

    2015-05-01

    The removal of estrogenicity in a University of Cape Town-biological nutrient removal (UCT-BNR) wastewater treatment process was investigated using pilot and bench scale systems, batch experiments and mathematical modeling. In the pilot BNR process, 96 ± 5% of the estrogenicity exerted by the influent wastewater was removed by the treatment process. The degradation efficiencies in the anaerobic, anoxic and aerobic zones of the pilot BNR bioreactor were 11 ± 9%, 18 ± 2% and 93 ± 10%, respectively. In order to further understand the performance of the BNR process in the removal of estrogenicity from wastewater, a bench scale BNR process was operated with synthetic wastewater dosed with E1 and E2. The removal of estrogenicity in the bench scale system (95 ± 5%) was comparable to the pilot BNR process and the degradation efficiencies were estimated to be 8 ± 0.8%, 38 ± 4% and 85 ± 22% in the anaerobic, anoxic and aerobic zones, respectively. A biotransformation model developed to predict the fate of E1 and E2 in batch tests using the sludge from the BNR process was calibrated using the data from the experiments. The biotransformation rate constants for the transformation of E2 to E1 were estimated as 71 ± 1.5, 31 ± 3.3 and 1 ± 0.9 L g COD{sup −1} d{sup −1} for the aerobic, anoxic and anaerobic batch tests, respectively, while the corresponding biotransformation rate constants for the transformation of E1 were estimated to be 7.3 ± 1.0, 3 ± 2.0, and 0.85 ± 0.6 L·g COD{sup −1} d{sup −1}. A steady state mass balance model formulated to describe the interactions between E2 and E1 in BNR activated sludge reasonably described the fate of E1 and E2 in the BNR process. - Highlights: • Comparable estrogenicity removal was observed from two BNR processes. • Pseudo first order model described the transformation of E2 and E1 in BNR process. • Biotransformation of E1 in BNR activated sludge controls the degradation of E2.

  16. Recent advances in nutrient removal and recovery in biological and bioelectrochemical systems.

    Science.gov (United States)

    Nancharaiah, Y V; Venkata Mohan, S; Lens, P N L

    2016-09-01

    Nitrogen and phosphorous are key pollutants in wastewater to be removed and recovered for sustainable development. Traditionally, nitrogen removal is practiced through energy intensive biological nitrification and denitrification entailing a major cost in wastewater treatment. Recent innovations in nitrogen removal aim at reducing energy requirements and recovering ammonium nitrogen. Bioelectrochemical systems (BES) are promising for recovering ammonium nitrogen from nitrogen rich waste streams (urine, digester liquor, swine liquor, and landfill leachate) profitably. Phosphorus is removed from the wastewater in the form of polyphosphate granules by polyphosphate accumulating organisms. Alternatively, phosphorous is removed/recovered as Fe-P or struvite through chemical precipitation (iron or magnesium dosing). In this article, recent advances in nutrients removal from wastewater coupled to recovery are presented by applying a waste biorefinery concept. Potential capabilities of BES in recovering nitrogen and phosphorous are reviewed to spur future investigations towards development of nutrient recovery biotechnologies. PMID:27053446

  17. Treatment of high strength leachate by biological nutrient removal processes

    International Nuclear Information System (INIS)

    This study describes the performance of a pilot-scale A/O system with respect to not only conventional wastewater quality parameters, but also specific volatile and semi-volatile organics. Hydraulic loadings were increased from 1.0 to 3.0 m3/d in two stages. The leachate was characterized by highly variable BOD, COD, TKN, and NH3-N concentrations ranging from 540-7185, 2040-8470, 501-1294, and 321-1000 mg/l respectively with over 91% of the BOD and 95% of the COD in soluble form. Concentrations of VOCs primarily benzene, chlorobenzene, ethylbenzene, toluene, o-xylene, m and p-xylene, 1,1-dichloroethane, and trichloroethylene ranging from 0.2 to 81.4 μg/l were reduced to below detection levels in the A/O system. At the three loadings investigated in the study i.e. 1, 2, and 3 m3 /d, the system affected excellent removals of organics and nitrogen, with reductions of soluble BOD (SBOD), total BOD, soluble COD (SCOD), COD, TKN, NH3-N, and total nitrogen of 91-100%, 87-97%, 65-93%, 57-91%, 84-96%, 99.96-99.97%, and 81-90% respectively. At the various loadings investigated in this study, effluent concentrations of SBOD, BOD,COD, SCOD, TKN, NH3-N, and nitrates as low as 4, 56, 685, 608, 35.2, 0.6, and 28.8 mg/l respectively were routinely achieved. Furthermore, despite operating at high mixed liquor solids in the 5000-6500 mg/l range, and the adversely long hydraulic residence time in the clarifier of 2 days, effluent total and volatile suspended solids concentrations of about 50 and 30 mg/l were achieved. The A/O system was not only capable of achieving the required sewer discharge criteria but it also demonstrated the achievability of surface discharge criteria, thus eliminating the need for additional treatment at the municipal wastewater treatment facilities. The system operated in a very stable fashion resisting the wide fluctuations in influent quality. (author)

  18. Cassava stillage and its anaerobic fermentation liquid as external carbon sources in biological nutrient removal*

    OpenAIRE

    Bu, Fan; Hu, Xiang; Xie, Li; Zhou, Qi

    2015-01-01

    The aim of this study was to investigate the effects of one kind of food industry effluent, cassava stillage and its anaerobic fermentation liquid, on biological nutrient removal (BNR) from municipal wastewater in anaerobic-anoxic-aerobic sequencing batch reactors (SBRs). Experiments were carried out with cassava stillage supernatant and its anaerobic fermentation liquid, and one pure compound (sodium acetate) served as an external carbon source. Cyclic studies indicated that the cassava by-p...

  19. A Modified Oxidation Ditch with Additional Internal Anoxic Zones for Enhanced Biological Nutrient Removal

    Institute of Scientific and Technical Information of China (English)

    LIU Wei; YANG Dianhai; XU Li; SHEN Changming

    2013-01-01

    A novel modified pilot scale anaerobic oxidation ditch with additional internal anoxic zones was operated experimentally,aiming to study the improvement of biological nitrogen and phosphorus removal and the effect of enhanced denitrifying phosphorus removal in the process.Under all experimental conditions,the anaerobic-oxidation ditch with additional internal anoxic zones and an internal recycle ratio of 200% had the highest nutrient removal efficiency.The effluent NH+4-N,total nitrogen(TN),PO34--P and total phosphorus(TP)contents were 1.2 mg·L-1,13 mg·L-1,0.3 mg·L-1 and 0.4 mg·L-1,respectively,all met the discharge standards in China.The TN and TP removal efficiencies were remarkably improved from 37% and 50% to 65% and 88% with the presence of additional internal anoxic zones and internal recycle ratio of 200%.The results indicated that additional internal anoxic zones can optimize the utilization of available carbon source from the anaerobic outflow for denitrification.It was also found that phosphorus removal via the denitrification process was stimulated in the additional internal anoxic zones,which was beneficial for biological nitrogen and phosphorus removal when treating wastewater with a limited carbon source.However,an excess internal recycle would cause nitrite to accumulate in the system.This seems to be harmful to biological phosphorus removal.

  20. Benchmarking biological nutrient removal in wastewater treatment plants: influence of mathematical model assumptions

    DEFF Research Database (Denmark)

    Flores-Alsina, Xavier; Gernaey, Krist V.; Jeppsson, Ulf

    2012-01-01

    This paper examines the effect of different model assumptions when describing biological nutrient removal (BNR) by the activated sludge models (ASM) 1, 2d & 3. The performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) benchmark wastewater treatment plant...... of the non-reactive TSS sedimentation and transport in the reference case with the full set of ASM processes. Finally, the third set of models is based on including electron acceptor dependency of biomass decay rates for ASM1 (WWTP1) and ASM2d (WWTP2). The results show that incorporation of a reactive...... settler: (1) increases the hydrolysis of particulates; (2) increases the overall plant's denitrification efficiency by reducing the SNOx concentration at the bottom of the clarifier; (3) increases the oxidation of COD compounds; (4) increases XOHO and XANO decay; and, finally, (5) increases the growth...

  1. Biological nutrient removal by internal circulation upflow sludge blanket reactor after landfill leachate pretreatment.

    Science.gov (United States)

    Abood, Alkhafaji R; Bao, Jianguo; Abudi, Zaidun N

    2013-10-01

    The removal of biological nutrient from mature landfill leachate with a high nitrogen load by an internal circulation upflow sludge blanket (ICUSB) reactor was studied. The reactor is a set of anaerobic-anoxic-aerobic (A2/O) bioreactors, developed on the basis of an expended granular sludge blanket (EGSB), granular sequencing batch reactor (GSBR) and intermittent cycle extended aeration system (ICEAS). Leachate was subjected to stripping by agitation process and poly ferric sulfate coagulation as a pretreatment process, in order to reduce both ammonia toxicity to microorganisms and the organic contents. The reactor was operated under three different operating systems, consisting of recycling sludge with air (A2/O), recycling sludge without air (low oxygen) and a combination of both (A2/O and low oxygen). The lowest effluent nutrient levels were realised by the combined system of A2/O and low oxygen, which resulted in effluent of chemical oxygen demand (COD), NH3-N and biological oxygen demand (BOD5) concentrations of 98.20, 13.50 and 22.50 mg/L. The optimal operating conditions for the efficient removal of biological nutrient using the ICUSB reactor were examined to evaluate the influence of the parameters on its performance. The results showed that average removal efficiencies of COD and NH3-N of 96.49% and 99.39%, respectively were achieved under the condition of a hydraulic retention time of 12 hr, including 4 hr of pumping air into the reactor, with dissolved oxygen at an rate of 4 mg/L and an upflow velocity 2 m/hr. These combined processes were successfully employed and effectively decreased pollutant loading. PMID:24494501

  2. Source Separation of Urine as an Alternative Solution to Nutrient Management in Biological Nutrient Removal Treatment Plants.

    Science.gov (United States)

    Jimenez, Jose; Bott, Charles; Love, Nancy; Bratby, John

    2015-12-01

    Municipal wastewater contains a mixture of brown (feces and toilet paper), yellow (urine), and gray (kitchen, bathroom and wash) waters. Urine contributes approximately 70-80% of the nitrogen (N), 50-70% of the phosphorus (P) load and 60-70% of the pharmaceutical residues in normal domestic sewage. This study evaluated the impact of different levels of source separation of urine on an existing biological nutrient removal (BNR) process. A process model of an existing biological nutrient removal (BNR) plant was used. Increasing the amount of urine diverted from the water reclamation facilities, has little impact on effluent ammonia (NH₃-N) concentration, but effluent nitrate (NO₃-N) concentration decreases. If nitrification is necessary then no reduction in the sludge age can be realized. However, a point is reached where the remaining influent nitrogen load matches the nitrogen requirements for biomass growth, and no residual nitrogen needs to be nitrified. That allows a significant reduction in sludge age, implying reduced process volume requirements. In situations where nitrification is required, lower effluent nitrate (NO₃-N) concentrations were realized due to both the lower influent nitrogen content in the wastewater and a more favorable nitrogen-to-carbon ratio for denitrification. The external carbon requirement for denitrification decreases as the urine separation efficiency increases due to the lower influent nitrogen content in the wastewater and a more favorable nitrogen-to-carbon ratio for denitrification. The effluent phosphorus concentration decreases when the amount of urine sent to water reclamation facilities is decreased due to lower influent phosphorus concentrations. In the case of chemical phosphate removal, urine separation reduces the amount of chemicals required. PMID:26652123

  3. The role and control of sludge age in biological nutrient removal activated sludge systems.

    Science.gov (United States)

    Ekama, G A

    2010-01-01

    The sludge age is the most fundamental and important parameter in the design, operation and control of biological nutrient removal (BNR) activated sludge (AS) systems. Generally, the better the effluent and waste sludge quality required from the system, the longer the sludge age, the larger the biological reactor and the more wastewater characteristics need to be known. Controlling the reactor concentration does not control sludge age, only the mass of sludge in the system. When nitrification is a requirement, sludge age control becomes a requirement and the secondary settling tanks can no longer serve the dual purpose of clarifier and waste activated sludge thickeners. The easiest and most practical way to control sludge age is with hydraulic control by wasting a defined proportion of the reactor volume daily. In AS plants with reactor concentration control, nitrification fails first. With hydraulic control of sludge age, nitrification will not fail, rather the plant fails by shedding solids over the secondary settling tank effluent weirs.

  4. Investigation of the Effects of COD/TP Ratio on the Performance of a Biological Nutrient Removal System

    OpenAIRE

    Punrattanasin, Warangkana

    1997-01-01

    The laboratory-scale University of Cape Town (UCT) process was designed to investigate the effects of changing COD/TP ratios on the performance of biological nutrient removal (BNR) processes. Specific objectives of the research were to investigate the effects of COD/TP ratio on the rates of phosphorus removal, COD removal, nitrogen removal, PHB utilization and oxygen uptake. The system was fed with municipal wastewater and operated at 20° C. The influent COD concentration was held approximat...

  5. Biological nutrient removal from leachate using a pilot liquid-solid circulating fluidized bed bioreactor (LSCFB).

    Science.gov (United States)

    Eldyasti, Ahmed; Chowdhury, Nabin; Nakhla, George; Zhu, Jesse

    2010-09-15

    Biological treatment of landfill leachate is a concern due to toxicity, high ammonia, low biodegradable organic matter concentrations, and low carbon-to-nitrogen ratio. To study the reliability and commercial viability of leachate treatment using an integrated liquid-solid circulating fluidized bed bioreactor (LSCFB), a pilot-scale LSCFB was established at the Adelaide Pollution Control Plant, London, Ontario, Canada. Anoxic and aerobic columns were used to optimize carbon and nutrient removal capability from leachate using 600 microm lava rock with a total porosity of 61%, at empty bed contact times (EBCTs) of 0.55, 0.49, and 0.41 d. The LSCFB achieved COD, nitrogen, and phosphorus removal efficiencies of 85%, 80%, and 70%, respectively at a low carbon-to-nitrogen ratio of 3:1 and nutrients loading rates of 2.15 kg COD/(m(3) d), 0.70 kg N/(m(3) d), and 0.014 kg P/(m(3) d), as compared with 60-77% COD and 70-79% nitrogen removal efficiencies achieved by upflow anaerobic sludge blanket (UASB) and moving bed bioreactor (MBBR), respectively. The LSCFB effluent characterized by biological solids retention times (SRTs) of 31, 38 and 44 d. PMID:20510504

  6. Impact of membrane solid-liquid separation on design of biological nutrient removal activated sludge systems.

    Science.gov (United States)

    Ramphao, M; Wentzel, M C; Merritt, R; Ekama, G A; Young, T; Buckley, C A

    2005-03-20

    Installing membranes for solid-liquid separation into biological nutrient removal (BNR) activated sludge (AS) systems makes a profound difference not only in the design of the BNR system itself, but also in the design approach for the whole wastewater treatment plant (WWTP). In multizone BNR systems with membranes in the aerobic reactor and fixed volumes for the anaerobic, anoxic, and aerobic zones (i.e., fixed volume fractions), the mass fractions can be controlled (within a range) with the interreactor recycle ratios. This zone mass fraction flexibility is a significant advantage in membrane BNR systems over conventional BNR systems with SSTs, because it allows for changing of the mass fractions to optimize biological N and P removal in conformity with influent wastewater characteristics and the effluent N and P concentrations required. For PWWF/ADWF ratios in the upper range (f(q) approximately 2.0), aerobic mass fractions in the lower range (f(maer) secondary settling tanks is not as large (40% to 60%), the cost of the membranes can be offset against sludge thickening and stabilization costs. Moving from a flow-unbalanced raw wastewater system to a flow-balanced (f(q) = 1), low (usually settled) wastewater strength system can double the ADWF capacity of the biological reactor, but the design approach of the WWTP changes from extended aeration to include primary sludge stabilization. The cost of primary sludge treatment then has to be paid from the savings from the increased WWTP capacity.

  7. Biological Nutrient Removal Model No. 2 (BNRM2): a general model for wastewater treatment plants.

    Science.gov (United States)

    Barat, R; Serralta, J; Ruano, M V; Jiménez, E; Ribes, J; Seco, A; Ferrer, J

    2013-01-01

    This paper presents the plant-wide model Biological Nutrient Removal Model No. 2 (BNRM2). Since nitrite was not considered in the BNRM1, and this previous model also failed to accurately simulate the anaerobic digestion because precipitation processes were not considered, an extension of BNRM1 has been developed. This extension comprises all the components and processes required to simulate nitrogen removal via nitrite and the formation of the solids most likely to precipitate in anaerobic digesters. The solids considered in BNRM2 are: struvite, amorphous calcium phosphate, hidroxyapatite, newberite, vivianite, strengite, variscite, and calcium carbonate. With regard to nitrogen removal via nitrite, apart from nitrite oxidizing bacteria two groups of ammonium oxidizing organisms (AOO) have been considered since different sets of kinetic parameters have been reported for the AOO present in activated sludge systems and SHARON (Single reactor system for High activity Ammonium Removal Over Nitrite) reactors. Due to the new processes considered, BNRM2 allows an accurate prediction of wastewater treatment plant performance in wider environmental and operating conditions. PMID:23552235

  8. Application of Moving Bed Biofilm Process for Biological Organics and Nutrients Removal from Municipal Wastewater

    OpenAIRE

    M. Kermani; B BINA; Haji Movahedian; Amin, M. M.; M. Nikaein

    2008-01-01

    In this study, experiments have been conducted to evaluate the organics and nutrients removal from synthetic wastewater by a laboratory scale moving bed biofilm process. For nutrients removal, moving bed biofilm process has been applied in series with anaerobic, anoxic and aerobic units in four separate reactors. Moving bed biofilm reactors were operated continuously at different loading rates of nitrogen and Phosphorus. During optimum conditions, close to complete nitrification with average ...

  9. Cassava stillage and its anaerobic fermentation liquid as external carbon sources in biological nutrient removal*

    Science.gov (United States)

    Bu, Fan; Hu, Xiang; Xie, Li; Zhou, Qi

    2015-01-01

    The aim of this study was to investigate the effects of one kind of food industry effluent, cassava stillage and its anaerobic fermentation liquid, on biological nutrient removal (BNR) from municipal wastewater in anaerobic-anoxic-aerobic sequencing batch reactors (SBRs). Experiments were carried out with cassava stillage supernatant and its anaerobic fermentation liquid, and one pure compound (sodium acetate) served as an external carbon source. Cyclic studies indicated that the cassava by-products not only affected the transformation of nitrogen, phosphorus, poly-β-hydroxyalkanoates (PHAs), and glycogen in the BNR process, but also resulted in higher removal efficiencies for phosphorus and nitrogen compared with sodium acetate. Furthermore, assays for phosphorus accumulating organisms (PAOs) and denitrifying phosphorus accumulating organisms (DPAOs) demonstrated that the proportion of DPAOs to PAOs reached 62.6% (Day 86) and 61.8% (Day 65) when using cassava stillage and its anaerobic fermentation liquid, respectively, as the external carbon source. In addition, the nitrate utilization rates (NURs) of the cassava by-products were in the range of 5.49–5.99 g N/(kg MLVSS∙h) (MLVSS is mixed liquor volatile suspended solids) and 6.63–6.81 g N/(kg MLVSS∙h), respectively. The improvement in BNR performance and the reduction in the amount of cassava stillage to be treated in-situ make cassava stillage and its anaerobic fermentation liquid attractive alternatives to sodium acetate as external carbon sources for BNR processes. PMID:25845364

  10. Biotransformation of trace organic compounds by activated sludge from a biological nutrient removal treatment system.

    Science.gov (United States)

    Inyang, Mandu; Flowers, Riley; McAvoy, Drew; Dickenson, Eric

    2016-09-01

    The removal of trace organic compounds (TOrCs) and their biotransformation rates, kb (LgSS(-)(1)h(-)(1)) was investigated across different redox zones in a biological nutrient removal (BNR) system using an OECD batch test. Biodegradation kinetics of fourteen TOrCs with initial concentration of 1-36μgL(-)(1) in activated sludge were monitored over the course of 24h. Degradation kinetic behavior for the TOrCs fell into four groupings: Group 1 (atenolol) was biotransformed (0.018-0.22LgSS(-)(1)h(-)(1)) under anaerobic, anoxic, and aerobic conditions. Group 2 (meprobamate and trimethoprim) biotransformed (0.01-0.21LgSS(-)(1)h(-)(1)) under anoxic and aerobic conditions, Group 3 (DEET, gemfibrozil and triclosan) only biotransformed (0.034-0.26LgSS(-)(1)h(-)(1)) under aerobic conditions, and Group 4 (carbamazepine, primidone, sucralose and TCEP) exhibited little to no biotransformation (<0.001LgSS(-)(1)h(-)(1)) under any redox conditions. BNR treatment did not provide a barrier against Group 4 compounds. PMID:27309772

  11. Experimental investigation of the external nitrification biological nutrient removal activated sludge (ENBNRAS) system.

    Science.gov (United States)

    Hu, Zhi-Rong; Sötemann, S; Moodley, R; Wentzel, M C; Ekama, G A

    2003-08-01

    A systematic lab-scale experimental investigation is reported for the external nitrification (EN) biological nutrient removal (BNR) activated sludge (ENBNRAS) system, which is a combined fixed and suspended medium system. The ENBNRAS system was proposed to intensify the treatment capacity of BNR-activated sludge (BNRAS) systems by addressing two difficulties often encountered in practice: (a) the long sludge age for nitrification requirement; and (b) sludge bulking. In the ENBNRAS system, nitrification is transferred from the aerobic reactor in the suspended medium activated sludge system to a fixed medium nitrification system. Thus, the sludge age of the suspended medium activated sludge system can be reduced from 20 to 25 days to 8 to 10 days, resulting in a decrease in reactor volume per ML wastewater treated of about 30%. Furthermore, the aerobic mass fraction can also be reduced from 50% to 60% to 55% (if the anaerobic mass fraction is 15%), and thus complete denitrification in the anoxic reactors becomes possible. Research indicates that both the short sludge age and complete denitrification could ameliorate anoxic aerobic (AA) or low food/microorganism (F/M) ratio filamentous bulking, and hence reduce the surface area of secondary settling tanks or increase the treatment capacity of existing systems. The lab-scale experimental investigations indicate that the ENBNRAS system can obtain: (i) very good chemical oxygen demand (COD) removal, even with an aerobic mass fraction as low as 20%; (ii) high nitrogen removal, even for a wastewater with a high total kjeldahl nitrogen (TKN)/COD ratio, up to 0.14; (iii) adequate settling sludge (diluted sludge volume index [DSVI] <100 mL/g); and (iv) a significant reduction in oxygen demand.

  12. Application of Moving Bed Biofilm Process for Biological Organics and Nutrients Removal from Municipal Wastewater

    Directory of Open Access Journals (Sweden)

    M. Kermani

    2008-01-01

    Full Text Available In this study, experiments have been conducted to evaluate the organics and nutrients removal from synthetic wastewater by a laboratory scale moving bed biofilm process. For nutrients removal, moving bed biofilm process has been applied in series with anaerobic, anoxic and aerobic units in four separate reactors. Moving bed biofilm reactors were operated continuously at different loading rates of nitrogen and Phosphorus. During optimum conditions, close to complete nitrification with average ammonium removal efficiency of 99.72% occurred in the aerobic reactor. In the aerobic reactor, the average specific nitrification rate was 1.8 g NOx-N kg VSS-1 h-1. The results of the average effluent soluble COD concentration from each reactor showed that denitrification process in the second anoxic reactor consumed most of the biodegradable organic matter. As seen from the results, denitrification rate has increased with increasing NOx-N loading in the second anoxic reactor. The aerobic phosphate removal rate showed a good correlation to the anaerobic phosphate release rate. Moreover, phosphate removal rate showed a strong correlation to the phosphate loading rate in the aerobic reactor. In optimum conditions, the average SCOD, total nitrogen and phosphorus removal efficiencies were 96.9, 84.6 and 95.8%, respectively. This study showed that the moving bed biofilm process could be used as an ideal and efficient option for the total nutrient removal from municipal wastewater.

  13. Enhanced biological nutrient removal in modified carbon source division anaerobic anoxic oxic process with return activated sludge pre-concentration☆

    Institute of Scientific and Technical Information of China (English)

    Qin Lu; Haiyan Wu; Haoyan Li; Dianhai Yang

    2015-01-01

    A pilot-scale modified carbon source division anaerobic anoxic oxic (AAO) process with pre-concentration of returned activated sludge (RAS) was proposed in this study for the enhanced biological nutrient removal (BNR) of municipal wastewater with limited carbon source. The influent carbon source was fed in step while a novel RAS pre-concentration tank was adopted to improve BNR efficiency, and the effects of an influent carbon source distribution ratio and a RAS pre-concentration ratio were investigated. The results show that the removal efficiency of TN is mainly influenced by the carbon source distribution ratio while the TP removal relies on the RAS pre-concentration ratio. The optimum carbon source distribution ratio and RAS pre-concentration ratio are 60%and 50%, respectively, with an inner recycling ratio of 100%under the optimum steady operation of pilot test, reaching an average effluent TN concentration of 9.8 mg·L−1 with a removal efficiency of 63%and an average TP removal efficiency of 94%. The mechanism of nutrient removal is discussed and the kinetics is analyzed. The results reveal that the optimal carbon source distribution ratio provides sufficient denitrifying carbon source to each anoxic phase, reducing nitrate accumulation while the RAS pre-concentration ratio improves the condition of anaerobic zone to ensure the phosphorus release due to less nitrate in the returned sludge. Therefore, nitrifying bacteria, denitrifying bacteria and phosphorus accumulation organisms play an important role under the optimum condition, enhancing the performance of nutrient removal in this test.

  14. Enhanced biological nutrient removal by the alliance of a heterotrophic nitrifying strain with a nitrogen removing ecosystem

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    and COD, respectively. These results suggest that it was more efficient for both the ammonia and carbon nutrient removals in a reactor inoculated with a heterotrophic nitrifier at high Corg/N ratio, inferring that the heterotrophic nitrifers would be practically more available in the treatment of wastewater with high level of ammonia and COD.

  15. Impact of solids residence time on biological nutrient removal performance of membrane bioreactor.

    Science.gov (United States)

    Ersu, Cagatayhan Bekir; Ong, Say Kee; Arslankaya, Ertan; Lee, Yong-Woo

    2010-05-01

    Impact of long solids residence times (SRTs) on nutrient removal was investigated using a submerged plate-frame membrane bioreactor with anaerobic and anoxic tanks. The system was operated at 10, 25, 50 and 75 days SRTs with hydraulic retention times (HRTs) of 2 h each for the anaerobic and anoxic tanks and 8 h for the oxic tank. Recirculation of oxic tank mixed liquor into the anaerobic tank and permeate into the anoxic tank were fixed at 100% each of the influent flow. For all SRTs, percent removals of soluble chemical oxygen demand were more than 93% and nitrification was more than 98.5% but total nitrogen percent removal seemed to peak at 81% at 50 days SRT while total phosphorus (TP) percent removal showed a deterioration from approximately 80% at 50 days SRT to 60% at 75 days SRT. Before calibrating the Biowin((R)) model to the experimental data, a sensitivity analysis of the model was conducted which indicated that heterotrophic anoxic yield, anaerobic hydrolysis factors of heterotrophs, heterotrophic hydrolysis, oxic endogenous decay rate for heterotrophs and oxic endogenous decay rate of PAOs had the most impact on predicted effluent TP concentration. The final values of kinetic parameters obtained in the calibration seemed to imply that nitrogen and phosphorus removal increased with SRT due to an increase in anoxic and anaerobic hydrolysis factors up to 50 days SRT but beyond that removal of phosphorus deteriorated due to high oxic endogenous decay rates. This indirectly imply that the decrease in phosphorus removal at 75 days SRT may be due to an increase in lysis of microbial cells at high SRTs along with the low food/microorganisms ratio as a result of high suspended solids in the oxic tank. Several polynomial correlations relating the various calibrated kinetic parameters with SRTs were derived. The Biowin((R)) model and the kinetic parameters predicted by the polynomial correlations were verified and found to predict well the effluent water quality

  16. Enhanced Nutrient Removal with Upflow Biological Aerated Filter for Reclaimed Water

    Institute of Scientific and Technical Information of China (English)

    WANG Hai-dong; PENG Yong-zhen; WANG Shu-ying; ZHANG Yan-ping

    2007-01-01

    A two-stage upflow biological aerated filter was designed as an advanced treatment process to optimize the operating parameters and study the correlative factors influencing the efficiency of nitrification, denitrification and phosphorus removal. The experimental results showed that the final effluent of the two-stage upflow biofilter process operated in series could meet the stringent limits of the reclaimed water for the total nitrogen of 2mg/L, and total phosphorus of 0.3mg/L. The high treatment efficiency allowed the reactor operating at very high hydraulic loadings and reaching nearly complete nitrification and denitrification.

  17. Using sludge fermentation liquid to reduce the inhibitory effect of copper oxide nanoparticles on municipal wastewater biological nutrient removal.

    Science.gov (United States)

    Su, Yinglong; Chen, Yinguang; Zheng, Xiong; Wan, Rui; Huang, Haining; Li, Mu; Wu, Lijuan

    2016-08-01

    The deterioration of biological nutrient removal (BNR) can occur with the release of engineering nanomaterials into wastewater treatment plants (WWTPs). Also, large amounts of waste sludge are generated in WWTPs, which can be reutilized as a useful resource. In this study, the use of sludge fermentation liquid to reduce CuO nanoparticles (NPs) toxicity to municipal wastewater BNR was reported. In the BNR system supplemented with sodium acetate, which was widely used as additional carbon source of municipal wastewater in literatures, the appearance of 2.5 mg/L CuO NPs for 5.5 h decreased the total nitrogen (TN) removal efficiency from 81.4% to 59.0%, but the TN removal was recovered to 78.7% after sodium acetate was replaced by sludge fermentation liquid. It was found that CuO NPs induced excessive generation of reactive nitrogen species (RNS), which led to the disorder of redox status, low levels of energy and reduction equivalents generations, and deterioration of denitrification. Further investigation revealed that cysteine in fermentation liquid played a vital biological role in reducing nanotoxicity by facilitating the synthesis of glutathione, which reduced excessive RNS generation, increased key proteins expression, guaranteed the metabolisms of intracellular energy and substrate smoothly, and finally recovered the BNR performance. PMID:27161888

  18. Biological nutrient removal from municipal wastewater in sequencing batch biofilm reactors

    Energy Technology Data Exchange (ETDEWEB)

    Arnz, P.

    2001-07-01

    Enhanced biological phosphorus removal (EBPR) has only been put into practice in activated sludge systems. In recent years, the Sequencing Batch Biofilm Reactor (SBBR) has emerged as an alternative allowing EBPR to be achieved in a biofilm reactor. High efficiency of phosphate removal was demonstrated in a SBBR fed with synthetic wastewater containing acetate. The aim of this study was to investigate EBPR from municipal wastewater in semi full-scale and laboratory-scale SBBRs. The focus of the investigation in the semi full-scale reactor was on determination of achievable reaction rates and effluent concentrations under varying influent conditions throughout all seasons of a year. Interactions between nitrogen and phosphorus removal and the influence of backwashing on the reactor performance was examined. Summing up, it can be stated that the SBBR proved to be an attractive alternative to activated sludge systems. Phosphorus elimination efficiency was comparable to common systems but biomass sedimentation problems were avoided. In order to further exploit the potential of the SBBR and to achieve reactor performances superior to those of existing systems designing a special biofilm carrier material may allow to increase the phenomenon of simultaneous nitrification/denitrification while maintaining EBPR activity. (orig.) [German] Die vermehrte biologische Phosphorelimination (Bio-P) aus Abwasser wurde bisher nur in Belebtschlammsystemen praktiziert. In den letzten Jahren konnte jedoch gezeigt werden, dass sich durch die Anwendung des Sequencing Batch Biofilm Reactor (SBBR) - Verfahrens auch in Biofilmreaktoren Bio-P verwirklichen laesst. Versuche in Laboranlagen haben ergeben, dass sich eine weitgehende Phosphorelimination aufrecht erhalten laesst, wenn die Reaktoren mit einem ideal zusammengesetzten, synthetischen Abwasser beschickt werden. Ziel dieser Arbeit war es, Bio-P aus kommunalem Abwasser in SBBR-Versuchsanlagen im halbtechnischen und im Labormassstab zu

  19. Biological nutrients removal from the supernatant originating from the anaerobic digestion of the organic fraction of municipal solid waste.

    Science.gov (United States)

    Malamis, S; Katsou, E; Di Fabio, S; Bolzonella, D; Fatone, F

    2014-09-01

    This study critically evaluates the biological processes and techniques applied to remove nitrogen and phosphorus from the anaerobic supernatant produced from the treatment of the organic fraction of municipal solid waste (OFMSW) and from its co-digestion with other biodegradable organic waste (BOW) streams. The wide application of anaerobic digestion for the treatment of several organic waste streams results in the production of high quantities of anaerobic effluents. Such effluents are characterized by high nutrient content, because organic and particulate nitrogen and phosphorus are hydrolyzed in the anaerobic digestion process. Consequently, adequate post-treatment is required in order to comply with the existing land application and discharge legislation in the European Union countries. This may include physicochemical and biological processes, with the latter being more advantageous due to their lower cost. Nitrogen removal is accomplished through the conventional nitrification/denitrification, nitritation/denitritation and the complete autotrophic nitrogen removal process; the latter is accomplished by nitritation coupled with the anoxic ammonium oxidation process. As anaerobic digestion effluents are characterized by low COD/TKN ratio, conventional denitrification/nitrification is not an attractive option; short-cut nitrogen removal processes are more promising. Both suspended and attached growth processes have been employed to treat the anaerobic supernatant. Specifically, the sequencing batch reactor, the membrane bioreactor, the conventional activated sludge and the moving bed biofilm reactor processes have been investigated. Physicochemical phosphorus removal via struvite precipitation has been extensively examined. Enhanced biological phosphorus removal from the anaerobic supernatant can take place through the sequencing anaerobic/aerobic process. More recently, denitrifying phosphorus removal via nitrite or nitrate has been explored. The removal of

  20. A modified UCT method for biological nutrient removal: configuration and performance.

    Science.gov (United States)

    Vaiopoulou, E; Aivasidis, A

    2008-07-01

    A pilot-scale prototype activated sludge system is presented, which combines both, the idea of University of Cape Town (UCT) concept and the step denitrification cascade for removal of carbon, nitrogen and phosphorus. The experimental set-up consists of an anaerobic selector and stepwise feeding in subsequent three identical pairs of anoxic and oxic tanks. Raw wastewater with influent flow rates ranging between 48 and 168 l d(-1) was fed to the unit at hydraulic residence times (HRTs) of 5-18 h and was distributed at percentages of 60/25/15%, 40/30/30% and 25/40/35% to the anaerobic selector, 2nd and 3rd anoxic tanks, respectively (influent flow distribution before the anaerobic selector). The results for the entire experimental period showed high removal efficiencies of organic matter of 89% as total chemical oxygen demand removal and 95% removal for biochemical oxygen demand, 90% removal of total Kjeldahl nitrogen and total nitrogen removal through denitrification of 73%, mean phosphorus removal of 67%, as well as excellent settleability. The highest removal efficiency and the optimum performance were recorded at an HRT of about 9h and influent flow rate of 96 l d(-1), in which 60% is distributed to the anaerobic selector, 25% to the second anoxic tank and 15% to the last anoxic tank. Consequently, the plant configuration enhanced removal efficiency, optimized performance, saved energy, formed good settling sludge and provided operational assurance.

  1. Assessment of full-scale biological nutrient removal systems upgraded with physico-chemical processes for the removal of emerging pollutants present in wastewaters from Mexico.

    Science.gov (United States)

    Estrada-Arriaga, Edson Baltazar; Cortés-Muñoz, Juana Enriqueta; González-Herrera, Arturo; Calderón-Mólgora, César Guillermo; de Lourdes Rivera-Huerta, Ma; Ramírez-Camperos, Esperanza; Montellano-Palacios, Leticia; Gelover-Santiago, Silvia Lucila; Pérez-Castrejón, Sara; Cardoso-Vigueros, Lina; Martín-Domínguez, Alejandra; García-Sánchez, Liliana

    2016-11-15

    Two full-scale biological nutrient removal systems upgraded with three physico-chemical processes (coagulation, chemical precipitation, and neutral Fenton) were evaluated in order to determine the removal of emerging pollutants (EPs) present in municipal wastewater from Mexico. Between 41 and 55 EPs were detected in the influents of two wastewater treatment plants (WWTPs), including personal care products (PPCPs), antibiotics, analgesics, antiepileptics, antilipidemics, antihypertensives, antiseptics, stimulants, and hormones. Emerging pollutants were detected at concentrations ranging from 0.69ng/L to 94,600ng/L. High concentrations of emerging pollutants were found during dry season. WWTP 1, integrated by oxidation ditches and UV light lamps, showed removal efficiencies of EPs between 20% and 22%. On the other hand, WWTP 2 consisted of anaerobic/anoxic/aerobic tanks coupled with two disinfection processes; chlorine dioxide and UV light lamps, for which the removal of EPs was significant (up to 80%). The concentrations of emerging pollutants in WWTP 1 effluent was found within a rangetreatment for the two effluents from the WWTPs is promising for the removal of emerging pollutants (up to 100%) and for assuring high quality of treated water. PMID:27457673

  2. Fate of dissolved organic nitrogen during biological nutrient removal wastewater treatment processes.

    Science.gov (United States)

    Liu, Bing; Lin, Huirong; Yu, Guozhong; Zhang, Shenghua; Zhao, Chengmei

    2013-04-01

    Due to its potential to form toxic nitrogenous disinfection byproducts (N-DBPs), dissolved organic nitrogen (DON) is considered as one of the most important parameters in wastewater treatment plants (WWTP). This study describes a comprehensive investigation of variations in DON levels in orbal oxidation ditches. The results showed that DON increased gradually from 0.71 to 1.14 mg I(-1) along anaerobic zone, anoxic zone, aerobic zone 1 and aerobic 2. Molecular weight fractionation of DON in one anaerobic zone and one aerobic zone (aerobic zone 2) was performed. We found that the proportion of small molecular weight ( 20 kDa) showed opposite trend. This variation may have been caused due to the release of different types of soluble microbial products (SMPs) during biological processes. These SMPs contained both tryptophan protein-like and aromatic protein-like substances, which were confirmed by three-dimensional excitation-emission matrix (EEM) analysis. PMID:24620601

  3. Combined Pre-Precipitation, Biological Sludge Hydrolysis and Nitrogen Reduction - A Pilot Demonstration of Integrated Nutrient Removal

    DEFF Research Database (Denmark)

    Kristensen, G. H.; Jørgensen, P. E.; Strube, R.;

    1992-01-01

    A pilot study was performed to investigate advanced wastewater treatment by pre-precipitation in combination with biological nitrogen removal supported by biological sludge hydrolysis. The influent wastewater was pretreated by addition of a pre-polymerized aluminum salt, followed by flocculation...... and sedimentation. Chemical pretreatment resulted in 60% COD-reduction and 75% phosphorus reduction. The chemically precipitated primary sludge was exposed to anaerobic sludge hydrolysis at retention times of 1 and 2 days at temperatures in the range of 15-30°C. At a retention time of two days at 20°C, resulting......, resulting in high denitrification rates. Nitrogen reduction was performed based on the Bio-Denitro principle in an activated sludge system. Nitrogen was reduced from 45 mg/l to 9 mg/l and phosphorus was reduced from 11 mg/l to 0.5 mg/l. The sludge yield was low, approx. 0.3-0.4 gCOD/gCOD removed...

  4. Biological Nutrient Removal in a Full Scale Anoxic/Anaerobic/Aerobic/Pre-anoxic-MBR Plant for Low C/N Ratio Municipal Wastewater Treatment

    Institute of Scientific and Technical Information of China (English)

    胡香; 谢丽; 张善发; 杨殿海

    2014-01-01

    A novel full scale modified A2O (anoxic/anaerobic/aerobic/pre-anoxic)-membrane bioreactor (MBR) plant combined with the step feed strategy was operated to improve the biological nutrient removal (BNR) from low C/N ratio municipal wastewater in Southern China. Transformation of organic carbon, nitrogen and phosphorus, and membrane fouling were investigated. Experimental results for over four months demonstrated good efficiencies for chemical oxygen demand (COD) and 4NH+-N removal, with average values higher than 84.5%and 98.1%, re-spectively. A relatively higher total nitrogen (TN) removal efficiency (52.1%) was also obtained at low C/N ratio of 3.82, contributed by the configuration modification (anoxic zone before anaerobic zone) and the step feed with a distribution ratio of 1︰1. Addition of sodium acetate into the anoxic zone as the external carbon source, with a theoretical amount of 31.3 mg COD per liter in influent, enhanced denitrification and the TN removal efficiency in-creased to 74.9%. Moreover, the total phosphate (TP) removal efficiency increased by 18.0%. It is suggested that the external carbon source is needed to improve the BNR performance in treating low C/N ratio municipal waste-water in the modified A2O-MBR process.

  5. Nutrient removal at the waste water treatment plant at Wathlingen. Special aspects of the enhanced biological phosphorus removal; Naehrstoffelemination auf der Klaeranlage Wathlingen. Besonderheiten bei der erhoehten biologischen Phosphatelimination

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, D. [Fachhochschule Suderburg (Germany); Fladerer, F. [Fachhochschule Suderburg (Germany)

    1996-01-01

    The article describes the problem of the nutrient removal in communal wastewater treatment plants. As an example the investigations about the optimisation of the denitrification and the enhanced biological phosphorus removal on the Wathlingen Wastewater Treatment Plant are explained. In this case the most important subjects are the anaerobic P-release despite a high amount of nitrate in the return sludge entering the anerobic tank, followed by an anoxic P-uptake in the denitrification zone before entering the aerobic tank for nitrification. Furthermore there is a short description of improvement measures carried out. The obtained effluent values show the success of these improvements. The specific P-dynamic in the treatment system requires conclusions supporting the optimisation of the nutrient removal in treatment plants using enhanced biological P-elimination and denitrification before nitrification. (orig.) [Deutsch] Der Artikel befasst sich mit der Problematik der Naehrstoffelimination auf kommunalen Klaeranlagen. Am Beispiel der Untersuchungen zur Optimierung der Dentrifikation und erhoehten biologischen Phosphorelimination auf der Klaeranlage Wathlingen werden Besonderheiten der biologischen P-Elimination dargestellt. Dabei geht es vor allem um eine anaerobe P-Freisetzung bei intermittierender Schlammumwaelzung im anaeroben Becken und gleichzeitigen hohen Nitrateintraegen ueber den Ruecklaufschlamm. Ebenso erfolgt die Darstellung der sich anschliessenden anoxischen P-Aufnahme im vorgeschalteten Denitrifikationsbecken. Des weiteren werden die druchgefuehrten Optimierungen kurz beschrieben und die damit erzielten Ablaufwerte aufgefuehrt. Schlussfolgerungen fuer die Prozessfuehrung bei Anlagenkonfigurationen mit biologischer P-Elimination und vorgeschalteter Denitrifikation ergeben sich aus dem Phaenomen der anoxischen Phosphataufnahme. (orig.)

  6. Enhanced biological nutrients removal using an integrated oxidation ditch with vertical circle from wastewater by adding an anaerobic column

    Institute of Scientific and Technical Information of China (English)

    WANG Shu-mei; LIU Jun-xin

    2005-01-01

    Compared to conventional oxidation ditches, an integrated oxidation ditch with vertical circle(IODVC) has the characters of concise configuration, simple operation and maintenance, land saving and automatical sludge returning. By the utilization of vertical circulation, an aerobic zone and an anoxic zone can be unaffectedly formed in the IODVC. Therefore, COD and nitrogen can be efficiently removed. However, the removal efficiency of phosphorus was Iow in the IODVC. In the experiment described, a laboratory scale system to add an anaerobic column to the IODVC has been tested to investigate the removal of phosphorus from wastewater. The experimental results showed that the removal efficiency of TP with the anaerobic column was increased to 54.0 % from 22.3 % without the anaerobic column. After the acetic sodium was added into the influent as carbon sources, the mean TP removal efficency of 77.5 % was obtained. At the same time, the mean removal efficiencies of COD, TN and NH3-N were 92.2%, 81.6% and 98.1%, respectively, at 12 h of HRT and 21-25 d of SRT. The optimal operational conditions in this study were as follows: recycle rate = 1.5-2.0, COD/TN > 6, COD/TP > 40,COD loading rate = 0.26-0.32 kgCOD/(kgSS·d), TN loading rate =0.028-0.034 kgTN/(kgSS·d) and TP loading rate = 0.003-0.005kgTP/(kgSS·d), respectively.

  7. Implementation of biological nutrient removal from municipal wastewater in Finland - HUT/Savonlinna process, a challenge to the UCT process; Asumisjaeteveden biologisen ravinteiden poiston toteuttaminen Suomen oloissa - HUT/Savonlinna-prosessi UCT-prosessin haastajana

    Energy Technology Data Exchange (ETDEWEB)

    Kiuru, H. [Helsinki Univ. of Technology, Otaniemi (Finland)

    2000-07-01

    The laboratory for Environmental Engineering at the Helsinki University of Technology carried out two successive full-scale R and D projects on biological nutrient removal. As a result of these projects, Pihlajaniemi Wastewater Treatment at Savonlinna in 1991-1996, an activated sludge process, called the HUT/Savonlinna process, was developed. By making use of the organic carbon in wastewater and without any added chemicals, the process is able to reduce the phosphorus content of water by more than 90% and the nitrogen content by about 70%. Total phosphorus contents averaging less than 0.5 mg/l and total nitrogen contents of 8-12 mg/l are usual in the secondary settled wastewater. These projects demonstrated that biological nutrient removal from domestic wastewater would best be started in Finland with year-round complete nitrification. This is the most demanding phase in the removal of biological nutrients from municipal wastewater and also the most expensive way to treat municipal wastewater with the conventional aerated activated sludge process. From there, it would be natural to proceed to effective nitrogen removal by means of denitrification. In that way the operating costs of the treatment plant would be markedly reduced. Nitrogen removal could be implemented without any extension of the treatment plant beyond what would be needed for complete year-round nitrification. The chemical removal of phosphorus from wastewater carried out as simultaneous precipitation could then easily replaced by biological phosphorus removal. This procedure would bring the operating costs of the treatment plant below the level normal in the conventional treatment of municipal wastewaters with an activated sludge process with simultaneous phosphorus precipitation. For this modification the treatment plants would not even have to be enlarged. When biological nutrient removal from municipal wastewaters is implemented in Finland, the HUT/Savonlinna process will surely challenge the UCT

  8. Effects of nutrient loading on Anabaena flos-aquae biofilm: biofilm growth and nutrient removals.

    Science.gov (United States)

    Li, Xiaowei; Wei, Qun; Tu, Xiaojie; Zhu, Yuxuan; Chen, Yanfei; Guo, Lina; Zhou, Jun; Sun, Hongyun

    2016-01-01

    Effects of three different nutrient loadings (low nutrient loading, medium nutrient loading and high nutrient loading, denoted as LNS, MNS and HNS, respectively) on the structure and functions of algal biofilm using Anabaena flos-aquae were investigated using synthetic wastewater. Nutrients removal efficiencies, biofilm thickness, microalgae dehydrogenase activity (DHA) and exopolysaccharide (EPS) productions were examined. Results showed that the changes of nutrient concentration were insignificant after 4 days of experiment for the case of HNS condition; 9 days for the case of MNS condition, and 6 days for the case of LNS condition, respectively. The biofilm thickness, nutrient removal efficiencies, algae DHA and EPS productions increased with the increase of nutrient loadings in synthetic wastewater. For the case of HNS condition, the microalgal biofilm exhibited the best performance in terms of C, N and P removal efficiencies, reaching the removal rates of 68.45, 3.56 and 1.61 mg·L(-1)·d(-1) for C, N, P, respectively. This was likely because, fact with the high nutrient loading, the high biological activity could be achieved, thus resulting in high nutrient removals. The thickness of the biofilm in HNS condition was 75 μm, which was closely related to EPS production. DHA and EPS concentrations were 7.24 and 1.8 × 10(-2) mg·mm(-2), respectively. It was also shown that apart from the nutrient loading, the structure and functions of microalgal biofilm were also influenced by other factors, such as illumination and temperature. PMID:27438243

  9. Plant Leachate Nutrient Recovery with Biological, Thermal, and Photocatalytic Pretreatments

    Science.gov (United States)

    Wong, Les

    2015-01-01

    Plants are ideal for long term space travel: provide essential resources - oxygen, water, food; Water-soaked plants expel soluble nutrients in a leachate solution - toxins and wastes are also expelled and inhibit growth; biological, thermal, photocatalytic coupled with an acid digestion treatment will hopefully maximize recovery and remove wastes

  10. Nutrient removal from wastewater using an UCT hybrid system suspended biomass and bio films

    Energy Technology Data Exchange (ETDEWEB)

    Saldarriaga, J. C.; Garrido, J. M.

    2009-07-01

    Over the past two decades, several biological suspended sludge configurations have been proposed to accomplish biological nitrogen and phosphorus removal, and they all include the basic stages of an anaerobic zone, followed by an anoxic and aerobic zone. From all these process the University Cape Town (UCT) or modified UCT processes are broadly used for nutrient removal in urban sewage (Ekama 1983). (Author)

  11. An Investigation of the Biochemistry of Biological Phosphorus Removal

    OpenAIRE

    Erdal, Zeynep Kisoglu

    2002-01-01

    Although enhanced biological phosphorus removal (EBPR) and complete biological nutrient removal (BNR) systems can be operated successfully by experienced operators, the accuracy of design and strength of the scientific background need to be reinforced to enable accurate modeling and economically optimal design. One way to accomplish this would be through a better understanding of the biochemical mechanisms and microbial population dynamics that determine the reliability and efficiency of EBPR...

  12. Optimizing Nutrient Uptake in Biological Transport Networks

    Science.gov (United States)

    Ronellenfitsch, Henrik; Katifori, Eleni

    2013-03-01

    Many biological systems employ complex networks of vascular tubes to facilitate transport of solute nutrients, examples include the vascular system of plants (phloem), some fungi, and the slime-mold Physarum. It is believed that such networks are optimized through evolution for carrying out their designated task. We propose a set of hydrodynamic governing equations for solute transport in a complex network, and obtain the optimal network architecture for various classes of optimizing functionals. We finally discuss the topological properties and statistical mechanics of the resulting complex networks, and examine correspondence of the obtained networks to those found in actual biological systems.

  13. Microbial Communities in Danish Wastewater Treatment Plants with Nutrient Removal

    DEFF Research Database (Denmark)

    Mielczarek, Artur Tomasz

    -term investigations of the microbial community in full-scale wastewater treatment plants, where conventional identification, molecular identification by quantitative Fluorescent In Situ Hybridization and extensive process information related to treatment plant design and process performance have been compiled......Activated sludge treatment plants are the most used wastewater treatment systems worldwide for biological nutrient removal from wastewater. Nevertheless, the treatment systems have been for many years operated as so called “black-box”, where specific process parameters were adjusted without...... was devoted into detailed analysis of almost fifty full-scale treatment plants (Microbial Database over Danish Wastewater Treatment Plants.) in order to learn more about the activated sludge communities and the rules that govern their presence and growth. This is one of the first such comprehensive long...

  14. Investigation into biological nutrient removal from wastewater

    OpenAIRE

    Vabolienė, Giedrė; Matuzevičius, Algirdas Bronislovas

    2005-01-01

    Siekiant išvengti eutrofizacijos vandens telkiniuose, išleidžiant valytas nuotekas į uždarus ar mažai pratekančius vandens telkinius bei pakartotinai jas panaudojant kaip technologinį vandenį, būtina šalinti azotą ir fosforą. Viena iš naujausių azoto ir fosforo šalinimo technologijų – „BioBalance“ technologija pritaikyta Utenos miesto nuotekų valymo įrenginiuose. Šalinant fosforą biologiniu būdu didelės įtakos turi valomų nuotekų sudėtis, ypač svarbu žinoti BDS7/BP santykį nuotekose po mechan...

  15. Striking the balance between nutrient removal, greenhouse gas emissions, receiving water quality, and costs.

    Science.gov (United States)

    Falk, Michael W; Reardon, David J; Neethling, J B; Clark, David L; Pramanik, Amit

    2013-12-01

    This Water Environment Research Foundation study considered the relationship between varying nutrient-removal levels at wastewater treatment plants, greenhouse gas emissions, receiving water quality (measured by potential algal production), and costs. The effluent nutrient concentrations required by some U.S. permits are very low, approaching the technology-best-achievable performance. This study evaluated five different treatment levels at a nominal 40 ML/d (10 mgd) flow. Greenhouse gas emissions and costs increase gradually up to the technologies' best-achievable performance, after which they increase exponentially. The gradual increase is attributed to additional biological treatment facilities, increased energy and chemical use, and additional tertiary nitrogen and phosphorus removal processes. Within the limited focus of this study, the evaluation shows that a point of diminishing return is reached as nutrient-removal objectives approach the technology-best-achievable performance, where greenhouse gas emissions and cost of treatment increases rapidly while the potential for algal growth reduce marginally. PMID:24597046

  16. Nutrient removal from swine lagoon effluent by duckweed

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, B.A.; Cheng, J.; Classen, J.; Stomp, A.M.

    2000-04-01

    Three duckweed geographic isolates were grown on varying concentrations of swine lagoon effluent in a greenhouse to determine their ability to remove nutrients from the effluent. Duckweed biomass was harvested every other day over a 12-day period. Duckweed biomass production, nutrient loss from the swine lagoon effluent, and nutrient content of duckweed biomass were used to identify effluent concentrations/geographic isolate combinations that are effective in terms of nutrient utilization from swine lagoon effluent and production of healthy duckweed biomass. When Lemna minor geographic isolate 8627 was grown on 50% swine lagoon effluent, respective losses of TKN, NH{sub 3}-N, TP, OPO{sub 4}-P, TOC, K, Cu, and Zn were 83, 100, 49, 31, 68, 21, 28 and 67%.

  17. Biological systems combined for the treatment of coffee processing wastewater: II - Removal of nutrients and phenolic compounds - doi: 10.4025/actascitechnol.v35i3.13628

    Directory of Open Access Journals (Sweden)

    Ronaldo Fia

    2013-06-01

    Full Text Available Three treatment systems consisting of anaerobic filters with upward flow followed by constructed wetland systems (CW were evaluated for the removal of nutrients and phenolic compounds, in the treatment of coffee processing wastewater (WCP in Viçosa, Minas Gerais State. Filters were made of PVC (1.5 m high and 0.35 m diameter filled with gravel # 2 and CW were made of wooden boxes (1.5 m long, 0.4 m high and 0.5 m wide sealed by HDPE geomembrane and filled with gravel ‘zero’. The WCP had the pH adjusted with lime to values close to 7.0 and the nutrient concentration changed to obtain a BOD/N/P ratio of 100/5/1. As a result, hydraulic retention times longer than 160 h in all treatment systems during phase III had not promoted greater efficiencies for removal compared with the phase I, because the recovery time of the systems was inadequate. The F1+CW1 system that received the lowest organic load, showed a satisfactory performance with regard to the removal of nutrients (above 50%.  

  18. Enhanced Biological Phosphorus Removal for Liquid Dairy Manure

    OpenAIRE

    Hong, Yanjuan

    2009-01-01

    Enhanced biological phosphorus removal (EBPR) has been widely used in municipal wastewater treatment, but no previous studies have examined the application of EBPR to treat dairy manure. This study was conducted to evaluate the (i) performance of pilot-scale EBPR systems treating liquid dairy manure, to balance the ratio of nitrogen to phosphorus in manure to meet crop nutrient requirements, (ii) effects of dissolved oxygen and solids retention time on the efficiency of EBPR, and (iii) effect...

  19. Enhanced Biological Nutrients Removal in Modified Step-feed Anaerobic/Anoxic/Oxic Process%改进型分段进水厌氧/缺氧/好氧工艺强化营养物去除

    Institute of Scientific and Technical Information of China (English)

    王伟; 王淑莹; 彭永臻; 张善锋; 殷芳芳

    2009-01-01

    In order to enhance phosphorus removal in traditional step-feed anoxic/oxic nitrogen removal process, a modified pilot-scale step-feed anaerobic/anoxic/oxic (SFA~2/O) system was developed, which combined a reactor similar to UCT-type configuration and two-stage anoxic/oxic process. The simultaneous nitrogen and phosphorus removal capacities and the potential of denitrifying phosphorus removal, in particular, were investigated with four different feeding patterns using real municipal wastewater. The results showed that the feeding ratios (Q_1) in the first stage determined the nutrient removal performance in the SFA~2/O system. The average phosphorus removal efficiency increased from 19.17% to 96.25% as Q_1 was gradually increased from run 1 to run 4, but the nitrogen removal efficiency exhibited a different tendency, which attained a maximum 73.61% in run 3 and then decreased to 59.62% in run 4. As a compromise between nitrogen and phosphorus removal, run 3 (Q_1 = 0.45Q_(total)) was identified as the optimal and stable case with the maximum anoxic phosphorus uptake rate of 1.58 mg(g MLSS)~(-1)·h~(-1). The results of batch tests showed that ratio of the anoxic phosphate uptake capacity to the aerobic phosphate uptake capacity increased from 11.96% to 36.85% with the optimal influent feeding ratio to the system in run 3, which demonstrated that the denitrifying polyP accumulating organisms could be accumulated and contributed more to the total phosphorus removal by optimizing the inflow ratio distribution. However, the nitrate recirculation to anoxic zone and influent feeding ratios should be carefully controlled for carbon source saving.

  20. Performance evaluation of a modified step-feed anaerobic/anoxic/oxic process for organic and nutrient removal

    Institute of Scientific and Technical Information of China (English)

    A.R. Majdi Nasab; S.M. Soleymani; M. Nosrati; S.M. Mousavi

    2016-01-01

    A pilot scale modified step-feed process was improved to increase nutrient (N and P) and organic removal operations from municipal wastewater. It combined the step-feed process and a method named“University of Cape Town (UCT)”. The effect of nutrient ratios and inflow distribution ratios were studied. The highest uptake efficiency of 95%for chemical oxygen demand (COD) has been achieved at the inflow distribution ratio of 40/35/25. However, maximum removal efficiency obtained for total nitrogen (TN) and phosphorus at 93%and 78%, respectively. The average mixed liquor suspended solids (MLSS) was 5500 mg·L−1. In addition, convenient values for dissolved oxygen (DO) concentration, and pH were obtained throughout different stages. The proposed system was identified to be an appropriate enhanced biological nutrient removal process for wastewater treatment plants owing to relatively high nutrient removal, sturdy sludge settle ability and COD removal.

  1. Biological systems combined for the treatment of coffee processing wastewater: II - Removal of nutrients and phenolic compounds - doi: 10.4025/actascitechnol.v35i3.13628

    OpenAIRE

    Ronaldo Fia; Antonio Teixeira Matos; Fátima Resende Luiz Fia

    2013-01-01

    Three treatment systems consisting of anaerobic filters with upward flow followed by constructed wetland systems (CW) were evaluated for the removal of nutrients and phenolic compounds, in the treatment of coffee processing wastewater (WCP) in Viçosa, Minas Gerais State. Filters were made of PVC (1.5 m high and 0.35 m diameter) filled with gravel # 2 and CW were made of wooden boxes (1.5 m long, 0.4 m high and 0.5 m wide) sealed by HDPE geomembrane and filled with gravel ‘zero’. The WCP ...

  2. Biological removal of methanol from process condensate for the purpose of reclamation

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-ming; YANG Min; ZHANG Yu; GAO Meng-chun; ZHANG Jing

    2004-01-01

    The biological removal of methanol from condensate of ammonia manufacturing processes for the purpose of reclamation using contact type reactor was studied. Methanol of 60 mg/L was removed completely under an HRT of 1.12 h. Optimal inorganic nutrient dose was determined on evaluating methanol removal performance and dehydrogenase activities (DHA) under different nutrition doses. The optimal inorganic nutrient dose only gave an increase of conductivity of ca. 10 μs/cm2 in the effluent on treating synthetic condensate containing methanol of 30 mg/L. The results demonstrated that biological removal of methanol was effective for the purpose of recovering the methanol-bearing condensate.

  3. Biological Phosphorus Removal in a Moving Bed Biofilm Reactor

    OpenAIRE

    Helness, Herman

    2007-01-01

    Phosphorus (P) and nitrogen (N) removal from municipal wastewater is performed to prevent or reduce eutrophication in the receiving water.Both P and N can be removed physical/chemically as well as biologically. While biological processes have always dominated in N-removal, chemical P-removal is used in many cases. Biological P-removal using enhanced biological phosphorus removal (EBPR) is normally carried out in suspended culture (activated sludge) processes while biological N-removal (throug...

  4. Corn Stover Nutrient Removal Estimates for Central Iowa, USA

    Directory of Open Access Journals (Sweden)

    Douglas L. Karlen

    2015-07-01

    Full Text Available One of the most frequent producer-asked questions to those persons striving to secure sustainable corn (Zea mays L. stover feedstock supplies for Iowa’s new bioenergy conversion or other bio-product facilities is “what quantity of nutrients will be removed if I harvest my stover?” Our objective is to summarize six years of field research from central Iowa, U.S.A. where more than 600, 1.5 m2 samples were collected by hand and divided into four plant fractions: vegetative material from the ear shank upward (top, vegetative material from approximately 10 cm above the soil surface to just below the ear (bottom, cobs, and grain. Another 400 stover samples, representing the vegetative material collected directly from a single-pass combine harvesting system or from stover bales were also collected and analyzed. All samples were dried, ground, and analyzed to determine C, N, P, K, Ca, Mg, S, Al, B, Cu, Fe, Mn, and Zn concentrations. Mean concentration and dry matter estimates for each sample were used to calculate nutrient removal and estimate fertilizer replacement costs which averaged $25.06, $20.04, $16.62, $19.40, and $27.41 Mg−1 for top, bottom, cob, stover, and grain fractions, respectively. We then used the plant fraction estimates to compare various stover harvest scenarios and provide an answer to the producer question posed above.

  5. Nutrients in urine: energetic aspects of removal and recovery

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, M.; Schwegler, P.; Larsen, T.A. [EAWAG, Environmental Engineering, Duebendorf (Switzerland)

    2003-07-01

    The analysis of different removal and recovery techniques for nutrients in urine shows that in many cases recovery is energetically more efficient than removal and new-production for natural resources. Considering only the running electricity and fossil energy requirements for the traditional way of wastewater treatment and fertiliser production, the following specific energy requirements can be calculated: 45 MJ kg{sup -1}{sub N} for denitrification in a WWTP, 49 MJ kg{sup -1}{sub P} for P-precipitation in a WWTP, 45 MJ kg{sup -1}{sub N} for N-fertiliser and 29 MJ kg{sup -1}{sub P} for P-fertiliser production. These numbers are higher than the values derived for thermal volume reduction of urine (35 MJ kg{sup -1}{sub N} for eliminating 90% water) or production of struvite (102 MJ kg{sup -1}{sub N}, including 2.2 kg P). Considering only the electricity and fossil energy for the traditional way of wastewater treatment and fertiliser production, the energy value of 1 PE urine is 0.87 MJ PE{sup -1}d{sup -1} (fertiliser value: 0.44, wastewater treatment: 0.43 MJ PE{sup -1}d{sup -1}). A more detailed life cycle assessment (LCA) of the entire urine collection system, including the required materials and the environmental burden, support the energy analysis. The LCA compares conventional denitrification in a wastewater treatment plant with collecting urine in households, reducing the volume by evaporation and using it as a multi-nutrient fertiliser. The primary energy consumption for recovery and reuse of urine, including the nutrients N, P and K, is calculated with 65 MJ kg{sup -1}{sub N}, compared with 153 MJ kg{sup -1}{sub N} derived for the conventional 'recycling over the atmosphere'. (author)

  6. Nutrient removal from UASB effluent in agro-industries

    OpenAIRE

    Desmidt, Evelyn; Monballiu, Annick; De Clippeleir, Haydée; Verstraete, Willy; Meesschaert, Boudewijn

    2011-01-01

    Phosphorus and nitrogen are important elements, making a major contribution to agricultural and industrial development, but their release to natural water bodies are the main causes of eutrophication. Anaerobic digestion yields effluents rich in ammonium and phosphate and poor in biodegradable organic carbon, thereby making them less suitable for conventional biological nitrogen and phosphorus removal. In addition, the demand for fertilizers is increasing, energy prices are rising and global ...

  7. The micro and macro of nutrients across biological scales.

    Science.gov (United States)

    Warne, Robin W

    2014-11-01

    During the past decade, we have gained new insights into the profound effects that essential micronutrients and macronutrients have on biological processes ranging from cellular function, to whole-organism performance, to dynamics in ecological communities, as well as to the structure and function of ecosystems. For example, disparities between intake and organismal requirements for specific nutrients are known to strongly affect animal physiological performance and impose trade-offs in the allocations of resources. However, recent findings have demonstrated that life-history allocation trade-offs and even microevolutionary dynamics may often be a result of molecular-level constraints on nutrient and metabolic processing, in which limiting reactants are routed among competing biochemical pathways. In addition, recent work has shown that complex ecological interactions between organismal physiological states such as exposure to environmental stressors and infectious pathogens can alter organismal requirements for, and, processing of, nutrients, and even alter subsequent nutrient cycling in ecosystems. Furthermore, new research is showing that such interactions, coupled with evolutionary and biogeographical constraints on the biosynthesis and availability of essential nutrients and micronutrients play an important, but still under-studied role in the structuring and functioning of ecosystems. The purpose of this introduction to the symposium "The Micro and Macro of Nutrient Effects in Animal Physiology and Ecology" is to briefly review and highlight recent research that has dramatically advanced our understanding of how nutrients in their varied forms profoundly affect and shape ecological and evolutionary processes.

  8. Enhanced biological phosphorus removal employing EDTA disodium

    Energy Technology Data Exchange (ETDEWEB)

    Bojinova, D.; Velkova, R. [Higher Inst. of Chemical Technology, Sofia (Bulgaria)

    1996-12-31

    The biological phosphorus removal is a promising alternative to the conventional chemical technologies for processing of phosphate raw materials. The object of this study was the effect of EDTA disodium on the biotreatment of tunisian phosphorite with the strain of Aspergillus niger. The incubation was carried out in two nutritive mediums, with different phosphate content. The experimental results showed that the additives of EDTA disodium in the nutritive medium increased the rate of extraction of P{sub 2}O{sub 5} and shortened significantly the time for biological leaching. 5 refs., 3 figs., 2 tabs.

  9. Enhancement of nutrient removal from swine wastewater digestate coupled to biogas purification by microalgae Scenedesmus spp.

    Science.gov (United States)

    Prandini, Jean Michel; da Silva, Márcio Luís Busi; Mezzari, Melissa Paola; Pirolli, Mateus; Michelon, William; Soares, Hugo Moreira

    2016-02-01

    This work investigated the effects of swine wastewater-derived biogas on microalgae biomass production and nutrient removal rates from piggery wastewater concomitantly with biogas filtration. Photobioreactors with dominant Scenedesmus spp. were prepared using non-sterile digestate and exposed to different photoperiods. In the presence of biogas and autotrophic conditions microalgae yield of 1.1±0.2 g L(-1) (growth rate of 141.8±3.5 mg L(-1) d(-1)) was obtained leading to faster N-NH3 and P-PO4(3-) assimilation rate of 21.2±1.2 and 3.5±2.5 mg L(-1) d(-1), respectively. H2S up to 3000 ppmv was not inhibitory and completely removed. Maximum CO2 assimilation of 219±4.8 mg L(-1) d(-1) was achieved. Biological consumption of CH4 up to 18% v/v was verified. O2 up to 22% v/v was controlled by adding acetate to exacerbate oxygen demand by microorganisms. Microalgae-based wastewater treatment coupled to biogas purification accelerates nutrient removal concomitantly producing valuable biomass and biomethane. PMID:26700760

  10. Nutrient Recovery of Plant Leachates Under Thermal, Biological, and Photocatalytic Pretreatments

    Science.gov (United States)

    Wong, Les

    2015-01-01

    Nutrient recovery has always been a problem for long distance and long-term space missions. To allow humans to man these missions, a steady source of oxygen, water, and food are necessary for survival beyond Earth's atmosphere. Plants are currently an area of interest since they are capable of providing all three resources for life sustainability. We are currently interested in nutrient recovery for future plant growth and simple aqueous leachate extractions can recover some of the nutrients. However, leaching plants also removes water-soluble organic plant wastes, which inhibits plant growth if not separated properly. To combat the issues with waste and maximize nutrient recovery, we are attempting to pre-treat the plant matter using biological, thermal, and photocatalytic methods before subjecting the solution with variable-strength acid digestion. For the biological method, the inoculums: mixed heterotrophic/nitrifying bioreactor effluent and Trichoderma vessei are used in an attempt to liberate more nutrients from the plant matter. For the thermal method, plants are subjected to varying temperatures at different retention times to determine nutrient recovery. Lastly, the photocatalytic method utilizes TiO (sub 2)'s oxidizing abilities under specific pHs and retention times to reduce organic wastes and improve nutrient gains. A final acid digestion serves to liberate nutrients even further in order to maximize recovery. So far, we have tested ideal acid digestion variables for practicality and performance in our experiments. We found that a low retention time of 10 minutes and a high acid concentration of 0.1 and 1 mole HCl were the most effective at nutrient recovery. For space travel purposes, 0.1 mole currently looks like a viable acid digestion to use since it is relatively effective and sustainable from a mass and energy balance if acid recovery can be performed on waste brines. Biological pretreatments do not look to be too effective and the thermal and

  11. Hydrologic and biologic influences on stream network nutrient concentrations: Interactions of hydrologic turnover and concentration-dependent nutrient uptake

    Science.gov (United States)

    Mallard, John; McGlynn, Brian; Covino, Tim

    2016-04-01

    Stream networks lie in a crucial landscape position between terrestrial ecosystems and downstream water bodies. As such, whether inferring terrestrial watershed processes from watershed outlet nutrient signals or predicting the effect of observed terrestrial processes on stream nutrient signals, it is requisite to understand how stream networks can modulate terrestrial nutrient inputs. To date integrated understanding and modeling of physical and biological influences on nutrient concentrations at the stream network scale have been limited. However, watershed scale groundwater ‑ surface water exchange (hydrologic turnover), concentration-variable biological uptake, and the interaction between the two can strongly modify stream water nutrient concentrations. Stream water and associated nutrients are lost to and replaced from groundwater with distinct nutrient concentrations while in-stream nutrients can also be retained by biological processes at rates that vary with concentration. We developed an empirically based network scale model to simulate the interaction between hydrologic turnover and concentration-dependent nutrient uptake across stream networks. Exchange and uptake parameters were measured using conservative and nutrient tracer addition experiments in the Bull Trout Watershed, central Idaho. We found that the interaction of hydrologic turnover and concentration-dependent uptake combined to modify and subsequently stabilize in-stream concentrations, with specific concentrations dependent on the magnitude of hydrologic turnover, groundwater concentrations, and the shape of nutrient uptake kinetic curves. We additionally found that by varying these physical and biological parameters within measured ranges we were able to generate a spectrum of stream network concentration distributions representing a continuum of shifting magnitudes of physical and biological influences on in-stream concentrations. These findings elucidate the important and variable role

  12. Biological anoxic phosphorus removal in a continuous-flow external nitrification activated sludge system

    Energy Technology Data Exchange (ETDEWEB)

    Kapagiannidis, A. G.; Aivasidis, A.

    2009-07-01

    Application of Biological Nutrient Removal (BNR) process in wastewater treatment is necessitated for the protection of water bodies from eutrophication. an alternative BNR method is tested for simultaneous Carbon (C), Nitrogen (N) and Phosphorus (P) removal in a continuous-flow bench scale plant for municipal wastewater treatment. The plant operation is based on the activity of two microbial populations which grow under different operational conditions (two sludge system). (Author)

  13. Phosphorus removal and recovery from domestic wastewater in a novel process of enhanced biological phosphorus removal coupled with crystallization.

    Science.gov (United States)

    Zou, Haiming; Wang, Yan

    2016-07-01

    A new process of enhanced biological phosphorus removal coupled with crystallization recovery of phosphorus was developed here, where the feasibility of nutrients removal and potential for phosphorus recovery from domestic wastewater was further assessed. Results showed that an excellent nutrients removal and phosphorus recovery performance was achieved, in which the averaged COD, PO4(3-)-P and NO3(-)-N removal efficiencies were 82.6%, 87.5% and 91.6%, respectively and a total of 59.3% of phosphorus was recovered as hydroxyapatite. What's more, crystallization recovery of phosphorus greatly enhanced the biological phosphorus removal efficiency. After the incorporation of the phosphorus recovery column via side-stream, the phosphorus concentration of effluent was significantly decreased ranging from 1.24mg/L to 0.85mg/L, 0.52mg/L and 0.41mg/L at the lateral flow ratios of 0, 0.1, 0.2 and 0.3, respectively. The results obtained here would be beneficial to provide a prospective alternative for phosphorus removal and recovery from wastewater. PMID:27003794

  14. Removal of nutrients by algae from municipal wastewater contaminated with heavy metals

    OpenAIRE

    Aryal, Bigyan

    2015-01-01

    Selected species of algae (green algae and blue green algae) were cultivated in municipal wastewater using PBR (photo-bioreactor) bottles. Uptake of nutrients by these algae species was measured on different dates. From the results of the experiments, it was observed that a combination of certain blue green algae species (cyanobacteria) was able to remove most of the nutrients from the wastewater. The presence of heavy metal ions in the wastewater also affected the nutrient-absorbing capacit...

  15. Nutrient removal and microalgal biomass production on urine in a short light-path photobioreactor

    NARCIS (Netherlands)

    Tuantet, K.; Temmink, B.G.; Zeeman, G.; Janssen, M.G.J.; Wijffels, R.H.; Buisman, C.J.N.

    2014-01-01

    Due to the high nitrogen and phosphorus content, source-separated urine can serve as a major nutrient source for microalgae production. The aim of this study was to evaluate the nutrient removal rate and the biomass production rate of Chlorella sorokiniana being grown continuously in urine employing

  16. Nutrients, Recycling, and Biological Populations in Upwelling Ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Whitledge, T. E.

    1980-01-01

    Nutrient recycling has been studied in the upwelling areas of Baja California, Northwest Africa, and Peru. Regeneration by biological populations in these areas contributes significant quantities of recycled nitrogen which is utilized in productivity processes. Each area has a different combination of organisms which leads to differences in the relative contributions of zooplankton, nekton, or benthos to the nutrient cycles. Comparisons of ammonium regeneration rates of zooplankton and nekton-micronekton populations in the three upwelling areas show that zooplankton recycle relatively less nitrogen in the Baja California and Peru systems than nekton. In the Northwest Africa upwelling region, however, zooplankton, fish, and benthic inputs are all substantial. In recent years the Peruvian upwelling system has been altered with the decline of the anchoveta population and an increase in the importance of zooplankton in nutrient recycling. The distribution of recycled nitrogen (ammonium and urea) in transects across the shelf at 10°S and 15°S indicates that regeneration is relatively more important at 10°S in the region of the wide shelf. In both areas the distribution of ammonium and urea are not entirely coincident thereby indicating differences in their production and/or utilization.

  17. Expert systems guide biological phosphorus removal

    Energy Technology Data Exchange (ETDEWEB)

    Krichten, D.J.; Wilson, K.D.; Tracy, K.D. (Air Products and Chemicals, Inc., Allentown, PA (United States))

    1991-10-01

    There is a large body of knowledge regarding optimum control strategies for new secondary wastewater treatment technology using an anaerobic selector to provide biological phosphorus removal. However, because the selector technology is new and the concepts differ somewhat from those used in conventional activated sludge wastewater treatment, a method of communicating this knowledge to plant operators is needed. Traditional methods such as classroom training and operating manuals are of limited effectiveness. The commonplace availability and low cost of the personal computer (PC) makes it practical to use a computer program to communicate the type of information required to control a wastewater treatment plant. Knowledge-based systems technology, commonly referred to as expert systems (ES) technology, is easy to use, provides useful information regarding a consistent control strategy, relieves the anxiety associated with learning a new process,' and provides instruction for inexperienced personnel. ES technology does not require special formatted input and is therefore easily accessible. All information required by the program is readily available through routine laboratory analysis, common plant instrumentation, or direct user observation. The program was designed for all levels of computer users and will run on all IBM-compatible or Apple MacIntosh systems.

  18. Possibility in optimization of biological phosphorus removal

    Energy Technology Data Exchange (ETDEWEB)

    Schoenberger, R.

    1989-02-01

    The elimination-efficiency of wastewater treatment plants with biological phosphorus removal is often limited by the following aspects: Low concentrations of organic acids in influent wastewater, hydraulic- and load fluctuations, low anaerobic sludge detention time, transfer of nitrate into the anaerobic zone, phosphorus release in the final clarifier and in sludge treatment units, high effluent suspended solids content. In this context, the following optimization measures seem to be advantageous: 'Activated primary tanks' and 'activated sludge thickeners' are adequate techniques to raise the concentration of organic acids in the wastewater by pre-acidification. Simultaneous acidification takes place in an anaerobic sedimentation basin as realized in the EASC-process (extended anaerobic sludge contact). Below the sludge blanket of an EASC-sedimentation tank, anaerobic conditions can be maintained even in the case of nitrate input. Furthermore, this process is suitable to compensate load- and hydraulic fluctuations of wastewater. To avoid phosphorus release in the final clarifier, it is important to improve sludge settleability. If a low sludge blanket and/or high oxygen concentrations are maintained, phosphorus release in the final clarifier can be limited. Further reduction of total phosphorus is possible with filtration only. Measures against high return flow phosphorus loads are mechanical dewatering of excess sludge and chemical precipitation of digester supernatant.

  19. Removal of nutrients in various types of constructed wetlands.

    Science.gov (United States)

    Vymazal, Jan

    2007-07-15

    The processes that affect removal and retention of nitrogen during wastewater treatment in constructed wetlands (CWs) are manifold and include NH(3) volatilization, nitrification, denitrification, nitrogen fixation, plant and microbial uptake, mineralization (ammonification), nitrate reduction to ammonium (nitrate-ammonification), anaerobic ammonia oxidation (ANAMMOX), fragmentation, sorption, desorption, burial, and leaching. However, only few processes ultimately remove total nitrogen from the wastewater while most processes just convert nitrogen to its various forms. Removal of total nitrogen in studied types of constructed wetlands varied between 40 and 55% with removed load ranging between 250 and 630 g N m(-2) yr(-1) depending on CWs type and inflow loading. However, the processes responsible for the removal differ in magnitude among systems. Single-stage constructed wetlands cannot achieve high removal of total nitrogen due to their inability to provide both aerobic and anaerobic conditions at the same time. Vertical flow constructed wetlands remove successfully ammonia-N but very limited denitrification takes place in these systems. On the other hand, horizontal-flow constructed wetlands provide good conditions for denitrification but the ability of these system to nitrify ammonia is very limited. Therefore, various types of constructed wetlands may be combined with each other in order to exploit the specific advantages of the individual systems. The soil phosphorus cycle is fundamentally different from the N cycle. There are no valency changes during biotic assimilation of inorganic P or during decomposition of organic P by microorganisms. Phosphorus transformations during wastewater treatment in CWs include adsorption, desorption, precipitation, dissolution, plant and microbial uptake, fragmentation, leaching, mineralization, sedimentation (peat accretion) and burial. The major phosphorus removal processes are sorption, precipitation, plant uptake (with

  20. Biological Phosphorus Removal in a Moving Bed Biofilm Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Helness, Herman

    2007-09-15

    The scope of this study was to investigate use of the moving bed biofilm reactor (MBBR) process for biological phosphorus removal. The goal has been to describe the operating conditions required for biological phosphorus and nitrogen removal in a MBBR operated as a sequencing batch reactor (SBR), and determine dimensioning criteria for such a process

  1. Results of activated sludge plants applying enhanced biological phosphorus removal

    Energy Technology Data Exchange (ETDEWEB)

    Machado, A.; Pinto, M.; Neder, K.; Hoffmann, H.

    1989-02-01

    To stop the eutrophication in lakes and rivers, the input of nutrient and phosphorus compounds must be limited. The biological elimination of phosphorus describes a possibility, to reduce phosphorus in the biological stage of a treatment plant to a considerable extent. In this paper the process-system and the operation-results of a pilot plant and two municipal treatment plants are presented, where biological phosphorus reduction about 80% takes place without any constructional modifications.

  2. Nutrients removal using moving beds with aeration cycles

    International Nuclear Information System (INIS)

    Moving Bed Biofilm Reactors (MBBR) are based on the biomass growth over a media that moves into the reactor due to aeration, mechanical agitation or recirculation. These reactors have been gaining popularity and they are employed in hundreds of plants everywhere with different treatment purposes (organic matter removal, nitrification/denitrification), both for urban and industrial wastewater. (Author)

  3. Nutrient and biological conditions of selected small streams in the Edwards Plateau, central Texas, 2005-06, and implications for development of nutrient criteria

    Science.gov (United States)

    Mabe, Jeffrey A.

    2007-01-01

    During the summers of 2005 and 2006 the U.S. Geological Survey, in cooperation with the Texas Commission on Environmental Quality, evaluated nutrient and biological conditions in small streams in parts of the Edwards Plateau of Central Texas. Land-cover analysis was used to select 15 small streams that represented a gradient of conditions with the potential to affect nutrient concentrations across the study area, which comprises two of four subregions of the Edwards Plateau ecoregion. All 15 streams were sampled for water properties, nutrients, algae, benthic invertebrates, and fish in summer 2005, and eight streams were resampled in summer 2006. Streams that did not receive wastewater effluent had relatively low nutrient concentrations and were classified as oligotrophic; streams receiving wastewater effluent had relatively high nutrient concentrations and were classified as eutrophic. Nutrient concentrations measured in the least-disturbed streams closely matched the U.S. Environmental Protection Agency nutrient criteria recommendations based on estimated reference concentrations. Nitrogen/phosphorus ratios indicated streams not affected by wastewater effluent might be limited by phosphorus concentrations. Algal indicators of nutrient condition were closely related to dissolved nitrogen concentrations and streamflow conditions. Ambient dissolved nitrogen concentrations (nitrite plus nitrate) were positively correlated with benthic algal chlorophyll-a concentrations. The correlation of benthic algal chlorophyll-a with instantaneous nitrite plus nitrate load was stronger than correlations with ambient nutrients. Increased nutrient concentrations were associated with increased macroalgae cover, wider diel dissolved oxygen ranges, and reduced diel dissolved oxygen minimums. Benthic invertebrate aquatic life use scores generally were classified as High to Exceptional in study streams despite the influence of urbanization or wastewater effluent. Reductions in aquatic

  4. Nutrient removal in a closed silvofishery system using three mangrove species (Avicennia germinans, Laguncularia racemosa, and Rhizophora mangle).

    Science.gov (United States)

    De-León-Herrera, R; Flores-Verdugo, F; Flores-de-Santiago, F; González-Farías, F

    2015-02-15

    The removal of ammonium (NH4(+)), nitrite (NO2(-)), nitrate (NO3(-)), and phosphate (PO4(-3)) in a closed silvofishery system was examined using three mangrove species (i.e., Avicennia germinans, Laguncularia racemosa, and Rhizophora mangle). Specifically, six closed tanks were installed for this experiment with a population of 60 Dormitator latifrons fishes per tank. We planted 40 seedlings in each of three experimental tanks separated by species, while the remaining tanks were used as control. During 15 weeks, nutrient concentrations among the three mangrove systems presented no significant differences (P>0.05). However, nutrient removal variability was minimum during the last 2-5 weeks. Mangroves presented an average efficiency of 63% for the removal of NH4(+) and NO2(-). Contrary, the average removal potential of NO3(-) and PO4(-3) was 50%. Results from this study suggest that the three mangrove species could be used in a closed silvofishery systems for the biological removal of NH4(+), NO2(-), NO3(-), and PO4(-3). PMID:25499182

  5. Biological - Elwha River Dam Removal Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem...

  6. Comparison of Nutrients and Salinity on Phenanthrene Removal from Polluted Soil 

    Directory of Open Access Journals (Sweden)

    Maasoumeh Ravanipour

    2013-02-01

    Full Text Available Background and Objectives:The poor accessibility of microorganisms to PAHs in soil has limited success in the process of bioremediation as an effective method for removing pollutants from soils. Different physicochemical factors are effective on the rate of biodegradation. The main objective of this study is to assess effects of nutrient and salinity on phenanthrene removal from polluted soils.Materials and Methods:The soil having no organic and microbial pollution was first artificially polluted with phenanthrene then nutrients and salinity solution in two concentrations were added to it in order to have the proportion of 10% w:v (soil: water. After that a microbial mixture enable to degrade phenanthrene was added to the slurry and was aerated. Finally, the residual concentration of Phenanthrene in the soil was extracted by ultrasonic and was analyzed using GC. We measured the microbial populationusing MPN test. This study was conducted based on the two level full factorial design of experiment. Results: MPN test showed that the trend of microbial growth has experienced a lag growth. The full factorial design indicated that nutrient had the maximum effect on bioremediation; the rate of phenanthrene removal in the maximum nutrients - minimum salinity solution was 75.14%.Conclusion: This study revealed that the more nutrient concentration increases, the more degradation will be happened by microorganisms in the soils. However, salinity in the concentration used had no effect on inhabitation or promoting on the Phenanthrene removal.

  7. Removal and Utilization of Wastewater Nutrients for Algae Biomass and Biofuels

    OpenAIRE

    Griffiths, Erick W.

    2009-01-01

    The Logan City Environmental Department operates a facility that consists of 460 acres of fairly shallow lagoons (~ 5'deep) for biological wastewater treatment that meets targets for primary and secondary treatments (solids, biological oxygen demand (BOD), and pathogen removal). Significant natural algal growth occurs in these lagoons, which improves BOD removal through oxygenation and also facilitates N removal through volatilization as ammonia under high pH conditions created by algal grow...

  8. Nutrient removal performance and microbial characteristics of a full-scale IFAS-EBPR process treating municipal wastewater.

    Science.gov (United States)

    Bai, Yang; Zhang, Yaobin; Quan, Xie; Chen, Shuo

    2016-01-01

    This work describes the nutrient removal performance and microbial characteristics of a full-scale integrated fixed-film activated sludge-enhanced biological phosphorus removal (IFAS-EBPR) process for municipal wastewater treatment. The polymerase chain reaction-denaturing gradient gel electrophoresis results showed that the presence of bacteria in this process, including Nitrosomonas sp., Nitrospira sp., Nitrobacter sp., Pseudomonas sp. and Acinetobacter sp., clusters. The fluorescence in situ hybridization results implied that there were more nitrifiers and denitrifiers on the biofilm carriers than in the suspended sludge, whereas more phosphorus-accumulating organisms (PAOs) resided in the suspended sludge. With the cooperation of these functional microbial populations both on the biofilm carriers and in the suspended sludge, the chemical oxygen demand (COD), NH4(+)-N, total nitrogen (TN) and total phosphorus (TP) removal efficiencies were maintained at 84, 97, 70 and 81%, and the effluent concentrations of them averaged 30, 1.0, 11.5 and 0.6 mg/L, which all satisfy the Chinese discharge standard (COD <50 mg/L, NH4(+)-N <5 mg/L, TN <15 mg/L and TP <1 mg/L), respectively. Therefore, the IFAS-EBPR process is a reliable and effective process for nutrient removal. PMID:27003065

  9. Kinetic analysis of enhanced biological phosphorus removal in a hybrid integrated fixed film activated sludge process

    International Nuclear Information System (INIS)

    Hybrid integrated fixed film activated sludge is a promising process for the enhancement of nitrification, denitrification and phosphorus removal in conventional activated sludge systems that can be used for upgrading biological nutrient removal, particularly when they have space limitations or need modifications that will require large monetary expenses. In this research, successful implementation of hybrid integrated fixed film activated sludge process at temperate zone wastewater treatment facilities has been studied by the placement of fixed film media into aerobic, anaerobic and anoxic zones. The primary objective of this study was to investigate the incorporation of enhanced biological phosphorus removal into hybrid integrated fixed film activated sludge systems and study the interactions between the fixed biomass and the mixed liquor suspended solids with respect to substrate competition and nutrient removal efficiencies. A pilot-scale anaerobic-anoxic-oxic configuration system was used. The system was operated at different mean cell residence times and influent chemical oxygen demand/total phosphorus ratios and with split influent flows. The experimental results confirmed that enhanced biological phosphorus removal could be incorporated successfully into hybrid integrated fixed film activated sludge system, but the redistribution of biomass resulting from the integration of fixed film media and the competition of organic substrate between enhanced biological phosphorus removal and denitrification would affect performances. Also, kinetic analysis of the reactor with regarding to phosphorus removal has been studied with different kinetic models and consequently the modified Stover-Kincannon kinetic model has been chosen for modeling studies and experimental data analysis of the hybrid integrated fixed film activated sludge reactor

  10. Vegetation effects on floating treatment wetland nutrient removal and harvesting strategies in urban stormwater ponds.

    Science.gov (United States)

    Wang, Chih-Yu; Sample, David J; Bell, Cameron

    2014-11-15

    Floating treatment wetlands (FTWs) consist of emergent macrophytes that are placed on a floating mat in a pond for water treatment and aesthetic purposes. FTWs may have unique advantages with respect to treating urban runoff within existing retention ponds for excess nutrients. However, research is lacking in providing guidance on performance of specific species for treating urban runoff, and on timing of harvest. Harvesting is needed to remove nutrients permanently from the retention pond. We investigated vegetation effects on FTWs on nitrogen (N) and phosphorus (P) removal performance and storage in above-ground FTW macrophyte tissues. The study evaluated pickerelweed (PW, Pontederia cordata L.) and softstem bulrush (SB, Schoenoplectus tabernaemontani) over time in microcosms flushed with water obtained from a nearby urban retention pond in northern Virginia near Washington, DC. While the literature exhibits a wide range of experimental sizes, using the term mesocosm, we have chosen the term microcosm to reflect the small size of our vessel; and do not include effects of sediment. The experiment demonstrated PW outperformed SB for P and N removal. Based upon analysis of the accumulated nutrient removal over time, a harvest of the whole PW and SB plants in September or October is recommended. However, when harvesting only the aerial parts, we recommend harvesting above-ground PW tissues in July or August to maximize nutrient removal. This is because PW translocates most of its nutrients to below-ground storage organs in the fall, resulting in less nutrient mass in the above-ground tissue compared to the case in the summer (vegetative stage). Further research is suggested to investigate whether vegetation can be overly damaged from multiple harvests on an annual basis in temperate regions. PMID:25214393

  11. Nutrient removal and biogas upgrading by integrating freshwater algae cultivation with piggery anaerobic digestate liquid treatment.

    Science.gov (United States)

    Xu, Jie; Zhao, Yongjun; Zhao, Guohua; Zhang, Hui

    2015-08-01

    An integrated approach that combined freshwater microalgae Scenedesmus obliquus (FACHB-31) cultivation with piggery anaerobic digestate liquid treatment was investigated in this study. The characteristics of algal growth, biogas production, and nutrient removal were examined using photobioreactor bags (PBRbs) to cultivate S. obliquus (FACHB-31) in digestate with various digestate dilutions (the concentration levels of 3200, 2200, 1600, 1200, 800, and 400 mg L(-1) chemical oxygen demand (COD)) during 7-day period. The effects of the level of pollutants on nutrient removal efficiency and CO2 removal process were investigated to select the optimum system for effectively upgrade biogas and simultaneously reduce the nutrient content in digestate. The treatment performance displayed that average removal rates of COD, total nitrogen (TN), total phosphorous (TP), and CO2 were 61.58-75.29, 58.39-74.63, 70.09-88.79, and 54.26-73.81 %, respectively. All the strains grew well under any the dilution treatments. With increased initial nutrient concentration to a certain range, the CO4 content (v/v) of raw biogas increased. Differences in the biogas enrichment of S. obliquus (FACHB-31) in all treatments mainly resulted from variations in biomass productivity and CO2 uptake. Notably, the diluted digestate sample of 1600 mg L(-1) COD provided an optimal nutrient concentration for S. obliquus (FACHB-31) cultivation, where the advantageous nutrient and CO2 removals, as well as the highest productivities of biomass and biogas upgrading, were revealed. Results showed that microalgal biomass production offered real opportunities to address issues such as CO2 sequestration, wastewater treatment, and biogas production.

  12. Hydraulic retention time effects on wastewater nutrient removal and bioproduct production via rotating algal biofilm reactor.

    Science.gov (United States)

    Iman Shayan, Sahand; Agblevor, Foster A; Bertin, Lorenzo; Sims, Ronald C

    2016-07-01

    Rotating algal biofilm reactor (RABR) technology was successfully employed in an effective strategy to couple the removal of wastewater nutrients with accumulation of valuable bioproducts by grown algae. A secondary stage municipal wastewater was fed to the developed system and the effects of the hydraulic retention time (HRT) parameter on both nutrient removal and bioproduct production were evaluated under fed-batch operation mode. Two sets of bench scale RABRs were designed and operated with HRTs of 2 and 6days in order to provide competitive environment for algal growth. The HRT significantly affected nitrogen and phosphorus uptakes along with lipid and starch accumulations by microalgae in harvested biofilms. Domination of nitrogen removal in 2-day HRT with higher lipid accumulation (20% on dried weight basis) and phosphorus removal in 6-day HRT with higher starch production (27% on dried weight basis) was observed by comparing the performances of the RABRs in duplicate runs. PMID:27038261

  13. Impacts of multiwalled carbon nanotubes on nutrient removal from wastewater and bacterial community structure in activated sludge.

    Directory of Open Access Journals (Sweden)

    Reti Hai

    biological wastewater nutrient removal, and altered the diversity and structure of bacterial community in activated sludge.

  14. Characterization of the in situ ecophysiology of novel phylotypes in nutrient removal activated sludge treatment plants

    DEFF Research Database (Denmark)

    McIlroy, Simon Jon; Awata, Takanori; Nierychlo, Marta;

    2015-01-01

    An in depth understanding of the ecology of activated sludge nutrient removal wastewater treatment systems requires detailed knowledge of the community composition and metabolic activities of individual members. Recent 16S rRNA gene amplicon surveys of activated sludge wastewater treatment plants...... with nutrient removal indicate the presence of a core set of bacterial genera. These organisms are likely responsible for the bulk of nutrient transformations underpinning the functions of these plants. While the basic activities of some of these genera in situ are known, there is little to no information...... for the majority. This study applied microautoradiography coupled with fluorescence in situ hybridization (MAR-FISH) for the in situ characterization of selected genus-level-phylotypes for which limited physiological information is available. These included Sulfuritalea and A21b, both within the class...

  15. The influence of duckweed species diversity on biomass productivity and nutrient removal efficiency in swine wastewater.

    Science.gov (United States)

    Zhao, Zhao; Shi, Huijuan; Liu, Yang; Zhao, Hai; Su, Haifeng; Wang, Maolin; Zhao, Yun

    2014-09-01

    The effect of temperature, light intensity, nitrogen and phosphorus concentrations on the biomass and starch content of duckweed (Landoltia punctata OT, Lemna minor OT) in monoculture and mixture were assessed. Low light intensity promoted more starch accumulation in mixture than in monoculture. The duckweed in mixture had higher biomass and nutrient removal efficiency than those in monoculture in swine wastewater. Moreover, the ability of L. punctata C3, L. minor C2, Spirodela polyrhiza C1 and their mixtures to recovery nutrients and their biomass were analyzed. Results showed that L. minor C2 had the highest N and P content, while L. punctata C3 had the highest starch content, and the mixture of L. punctata C3 and L. minor C2 had the greatest nutrient removal rate and the highest biomass. Compared with L. punctata C3 and L. minor C2 in monoculture, their biomass in mixture increased by 17.0% and 39.8%, respectively. PMID:24998479

  16. Corn stover nutrient removal estimates for Central Iowa, U.S.A.

    Science.gov (United States)

    One of the most frequently asked questions to those striving to secure sustainable corn (Zea mays L.) stover feedstock supplies for Iowa’s new bioenergy conversion facilities is “what quantity of nutrients will be removed if I harvest my stover?”. Our objective is to summarize six years of field res...

  17. External Carbon Source Addition as a Means to Control an Activated Sludge Nutrient Removal Process

    DEFF Research Database (Denmark)

    Isaacs, Steven Howard; Henze, Mogens; Søeberg, Henrik;

    1994-01-01

    In alternating type activated sludge nutrient removal processes, the denitrification rate can be limited by the availability of readily-degradable carbon substrate. A control strategy is proposed by which an easily metabolizable COD source is added directly to that point in the process at which...

  18. Efficiency of three halophyte species in removing nutrients from saline water

    NARCIS (Netherlands)

    Lange, de H.J.; Paulissen, M.P.C.P.

    2016-01-01

    Saline wetlands may be well suited for purifying contaminated water from saline agriculture and aquaculture or from freshwater-based agriculture in areas subject to increased salinity. However, case studies on the nutrient removal efficiency of halophyte species are scarce, especially for tempera

  19. Biological removal of nitrogen from waste water

    Energy Technology Data Exchange (ETDEWEB)

    Dombrowski, T.; Lompe, D.; Wiesmann, U.

    1989-02-01

    The biological treatment of waste water with both a high organic (2500 mg/l DOC) and high ammonia concentration (600 mg/l NH/sub 4//sup +/-N) was investigated. The first step consists of a two step anaerobic cascade of fixed bed loop reactors with polyurethan foam particles as support material for bacterica. The aerobic treatment occurs in two aerated stirred tanks with sedimentation tanks and two separate sludge recycle systems each for heterotrophic and autotrophic biomass resulting in a degradation of organic compounds (first tank) and nitrification (second tank). Finally the nitrate is reduced by biological denitrification. By optimization the total hydraulic retention time could be reduced to 7 hr. Nitrification is the most sensitive step and can be on-line controlled by measurement of oxygen consumption.

  20. Suitability of macrophytes for nutrient removal from surface flow constructed wetlands receiving secondary treated sewage effluent in Queensland, Australia.

    Science.gov (United States)

    Greenway, M

    2003-01-01

    From a botanical perspective the major difference between waste stabilisation ponds and wetlands is the dominance of algae or floating plants in the former and emergent plants in the latter. Algae, floating and submerged plants remove nutrients directly from the water column whereas emergent species remove nutrients from the sediment. Water depth is a crucial factor in determining which plant types will become established. Surface flow constructed wetlands offer the greatest potential to grow a wide variety of different types of macrophytes. In assessing the suitability of plant species for nutrient removal, consideration must be given not only to nutrient uptake for growth but also storage of nutrients as plant biomass. A survey of macrophytes in 15 surface flow constructed wetlands treating secondary effluent was conducted in Queensland; 63 native species and 14 introduced species were found. Emergent species have been able to tolerate deeper water than in their natural environment and permanent waterlogging. All species grew well in the higher nutrient enriched wastewater. Submerged, floating leaved-attached and free floating species had the highest tissue nutrient content, followed by aquatic creepers. All these species remove nutrients from the water column. Emergent species had lower nutrient content but a greater biomass and were therefore able to store more nutrients per unit area of wetland. In order to maximise the efficiency of constructed wetlands for nutrient removal, a range of species should be used. Native species should be selected in preference to introduced/exotic species. PMID:14510202

  1. Evaluation of leaf removal as a means to reduce nutrient concentrations and loads in urban stormwater

    Science.gov (United States)

    Selbig, William R.

    2016-01-01

    While the sources of nutrients to urban stormwater are many, the primary contributor is often organic detritus, especially in areas with dense overhead tree canopy. One way to remove organic detritus before it becomes entrained in runoff is to implement a city-wide leaf collection and street cleaning program. Improving our knowledge of the potential reduction of nutrients to stormwater through removal of leaves and other organic detritus on streets could help tailor more targeted municipal leaf collection programs. This study characterized an upper ideal limit in reductions of total and dissolved forms of phosphorus and nitrogen in stormwater through implementation of a municipal leaf collection and street cleaning program in Madison, WI, USA. Additional measures were taken to remove leaf litter from street surfaces prior to precipitation events.

  2. Thermophilic biological nitrogen removal in industrial wastewater treatment.

    OpenAIRE

    Lopez-Vazquez, CM; Kubare, M.; Saroj, DP; Chikamba, C; Schwarz, J.; Daims, H.; Brdjanovic, D.

    2013-01-01

    Nitrification is an integral part of biological nitrogen removal processes and usually the limiting step in wastewater treatment systems. Since nitrification is often considered not feasible at temperatures higher than 40 °C, warm industrial effluents (with operating temperatures higher than 40 °C) need to be cooled down prior to biological treatment, which increases the energy and operating costs of the plants for cooling purposes. This study describes the occurrence of thermophilic biologic...

  3. Effect of Nutrient/Carbon Supplements on Biological Phosphate and Nitrate Uptake by Protozoan Isolates

    Science.gov (United States)

    Akpor, O. B.; Momba, M. N. B.; Okonkwo, J.

    This study was aimed at investigating the effect of nine different nutrient/carbon supplements in mixed liquor on nutrient uptake ability of three wastewater protozoan isolates, which have previously been screened for phosphate and nitrate uptake efficiency. The results revealed that over 50% of phosphate was removed in the presence of sodium acetate, glucose or sucrose. Similarly, nitrate uptake of over 60% was observed in the presence of sodium acetate, sodium succinate, glucose or sucrose. These trends were common in all the isolates. Chemical Oxygen Demand (COD) removal in the mixed liquor was only found to be significantly removed in mixed liquors that were supplemented with glucose, sucrose or sodium succinate. In the presence of sodium acetate, COD was observed to increase. The findings of this investigation have revealed that nutrient uptake and COD removal by the test protozoan isolates may be dependent primarily on the initial nutrient supplement in mixed liquor.

  4. Growth and efficiency of nutrient removal by Salix jiangsuensis J172 for phytoremediation of urban wastewater.

    Science.gov (United States)

    Shi, Xiang; Sun, Haijing; Pan, Hongwei; Chen, Yitai; Jiang, Zeping; Liu, Jianfeng; Wang, Shufeng

    2016-02-01

    Willows are a group of versatile tree species that may have multiple environmental applications. In the present study, Salix jiangsuensis J172 plants were grown in the fixed mats as an economic plant-based treatment system to evaluate its potential for removing nutrients in wastewater. Plants grew normally in wastewater compared with those in Hoagland solution. However, wastewater containing a high concentration of chlorine ions was toxic to S. jiangsuensis J172 plants. The plants accumulated large amounts of nitrogen and phosphorus in aboveground tissues under conditions of abundant supply. The removal efficiency for raw wastewater was 82.18-87.78 % for nitrogen, 57.35-65.58 % for phosphorus, and 58.24-59.90 % for chemical oxygen demand. Nutrient removal efficiency was positively correlated with the initial nutrient supply. The results show that S. jiangsuensis J172 grown in the fixed mat economic plant-based treatment system with nutrient-rich, eutrophic water may be an effective, low-cost phytoremediation technology to treat water containing undesirable levels of wastewater.

  5. Optimization of hard clams, polychaetes, physical disturbance and denitrifying bacteria of removing nutrients in marine sediment.

    Science.gov (United States)

    Shen, Hui; Thrush, Simon F; Wan, Xihe; Li, Hui; Qiao, Yi; Jiang, Ge; Sun, Ruijian; Wang, LiBao; He, Peimin

    2016-09-15

    Marine organisms are known to play important roles in transforming nutrients in sediments, however, guidelines to optimize sediment restoration are not available. We conducted a laboratory mesocosm experiment to investigate the role of hard clams, polychaetes, the degree of physical disturbance and denitrifying bacterial concentrations in removing total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) in marine sediments. Response surface methodology was employed to analyze the results of initial experiments and in a subsequent experiment identified optimal combinations of parameters. Balancing the TN, TP, TOC removal efficiency, our model predicted 39% TN removal, 33% TP removal, and 42% TOC removal for a 14-day laboratory bioremediation trial using hard clams biomass of 1.2kgm(-2), physical disturbance depth of 16.4cm, bacterial density of 0.18Lm(-2), and polychaetes biomass of 0.16kgm(-2), respectively. These results emphasize the value of combining different species in field-based bioremediation. PMID:27371956

  6. Removal of arsenic and iron removal from drinking water using coagulation and biological treatment.

    Science.gov (United States)

    Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Suja, Fatihah

    2016-02-01

    Effects of biological activated carbon (BAC), biological aerated filter (BAF), alum coagulation and Moringa oleifera coagulation were investigated to remove iron and arsenic contaminants from drinking water. At an initial dose of 5 mg/L, the removal efficiency for arsenic and iron was 63% and 58% respectively using alum, and 47% and 41% respectively using Moringa oleifera. The removal of both contaminants increased with the increase in coagulant dose and decrease in pH. Biological processes were more effective in removing these contaminants than coagulation. Compared to BAF, BAC gave greater removal of both arsenic and iron, removing 85% and 74%, respectively. Longer contact time for both processes could reduce the greater concentration of arsenic and iron contaminants. The addition of coagulation (at 5 mg/L dosage) and a biological process (with 15 or 60 min contact time) could significantly increase removal efficiency, and the maximum removal was observed for the combination of alum and BAC treatment (60 min contact time), with 100% and 98.56% for arsenic and iron respectively. The reduction efficiency of arsenic and iron reduced with the increase in the concentration of dissolved organics in the feedwater due to the adsorption competition between organic molecules and heavy metals.

  7. Removal of arsenic and iron removal from drinking water using coagulation and biological treatment.

    Science.gov (United States)

    Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Suja, Fatihah

    2016-02-01

    Effects of biological activated carbon (BAC), biological aerated filter (BAF), alum coagulation and Moringa oleifera coagulation were investigated to remove iron and arsenic contaminants from drinking water. At an initial dose of 5 mg/L, the removal efficiency for arsenic and iron was 63% and 58% respectively using alum, and 47% and 41% respectively using Moringa oleifera. The removal of both contaminants increased with the increase in coagulant dose and decrease in pH. Biological processes were more effective in removing these contaminants than coagulation. Compared to BAF, BAC gave greater removal of both arsenic and iron, removing 85% and 74%, respectively. Longer contact time for both processes could reduce the greater concentration of arsenic and iron contaminants. The addition of coagulation (at 5 mg/L dosage) and a biological process (with 15 or 60 min contact time) could significantly increase removal efficiency, and the maximum removal was observed for the combination of alum and BAC treatment (60 min contact time), with 100% and 98.56% for arsenic and iron respectively. The reduction efficiency of arsenic and iron reduced with the increase in the concentration of dissolved organics in the feedwater due to the adsorption competition between organic molecules and heavy metals. PMID:26837833

  8. Nutrients removal and nitrous oxide emission during simultaneous nitrification, denitrification, and phosphorus removal process: effect of iron.

    Science.gov (United States)

    Jia, Wenlin; Wang, Qian; Zhang, Jian; Yang, Weihua; Zhou, Xiaowei

    2016-08-01

    The short- and long-term influences of ferric iron (Fe(III)) on nutrients removal and nitrous oxide (N2O) emission during SNDPR process were evaluated. According to the continuous cycle experiments, it was concluded that the addition of Fe(III) could lower the nitrogen removal of the following cycle during SNDPR process, which was mainly induced by the chemical removal of phosphorus. However, the impacts were transitory, and simultaneous nitrogen and phosphorus removal would recover from the inhibition of Fe(III) after running certain cycles. Moreover, the addition of Fe(III) could stimulate N2O emission transitorily during SNDPR process. However, if Fe(III) was added into reactor continuously, the nitrogen removal would be improved, especially at low Fe load condition. It was because that the activity of NO reductase was enhanced by the addition of Fe. However, the low Fe load in reactor would induce more N2O emission. When Fe(III) load was 40 mg/L in the reactor, the N2O yield was 10 % higher than control. The TN removal was weakened when Fe(III) load reached to 60 mg/L, and the N2O yield was lower than control, due to the inhibition of the high Fe load on denitrification enzymes. PMID:27137189

  9. Influence of carbon source on nutrient removal performance and physical-chemical characteristics of aerobic granular sludge.

    Science.gov (United States)

    Lashkarizadeh, Monireh; Yuan, Qiuyan; Oleszkiewicz, Jan A

    2015-01-01

    The impact of carbon source variation on the physical and chemical characteristics of aerobic granular sludge and its biological nutrient (nitrogen and phosphorus) removal performance was investigated. Two identical sequencing batch reactors, R1 and R2, were set up. Granular biomass was cultivated to maturity using acetate-based synthetic wastewater. After mature granules in both reactors with simultaneous chemical oxygen demand (COD), ammonium and phosphorus removal capability were achieved, the feed of R2 was changed to municipal wastewater and R1 was continued on synthetic feed as control. Biological phosphorus removal was completely inhibited in R2 due to lack of readily biodegradable COD; however, the biomass maintained high ammonium and COD removal efficiencies. The disintegration of the granules in R2 occurred during the first two weeks after the change of feed, but it did not have significant impacts on settling properties of the sludge. Re-granulation of the biomass in R2 was then observed within 30 d after granules' disintegration when the biomass acclimated to the new substrate. The granular biomass in R1 and R2 maintained a Sludge Volume Index close to 60 and 47 mL g(-1), respectively, during the experimental period. It was concluded that changing the carbon source from readily biodegradable acetate to the more complex ones present in municipal wastewater did not have significant impacts on aerobic granular sludge characteristics; it particularly did not affect its settling properties. However, sufficient readily biodegradable carbon would have to be provided to maintain simultaneous biological nitrate and phosphorus removal. PMID:25719420

  10. Optimization of simultaneous biomass production and nutrient removal by mixotrophic Chlorella sp. using response surface methodology.

    Science.gov (United States)

    Lee, Yu-Ru; Chen, Jen-Jeng

    2016-01-01

    The bioprospecting of potentially mixotrophic microalgae in a constructed wetland was conducted. A locally isolated microalga, Chlorella sp., was grown to determine the effect of temperature, aeration rate, and cultivation time on simultaneous biomass production and nutrient removal from piggery wastewater using central composite design (CCD). The most important variable for the biomass productivity of Chlorella sp. was aeration rate, while that for lipid content and nutrient removal efficiency was cultivation time. Total nitrogen (TN) and total phosphorus (TP) removal efficiencies were higher than that of chemical oxygen demand (COD) from piggery wastewater. The CCD results indicate that the highest biomass productivity (79.2 mg L(-1) d(-1)) and simultaneous nutrient removal efficiency (TN 80.9%, TP 99.2%, COD 74.5%) were obtained with a cultivation temperature of 25 °C, a cultivation time of 5 days, and an air aeration rate of 1.6 L L(-1) min(-1). Palmitic acid (C16:0) and linoleic acid (C18:2) were both abundant in Chlorella sp. cells under mixotrophic cultivation with piggery wastewater.

  11. [Ecological stability on biological removal of iron and manganese filter under poor nutritional conditions].

    Science.gov (United States)

    Yang, Hong; Xiong, Xiao-Li; Duan, Xiao-Dong; Song, Li-Xin; Yu, Ping-Bo; Li, Wei; Zhang, Jie

    2010-01-01

    To supply necessary bacteria and available nutrients, a method of returning backwashing wastewater to the bio-filter for removal of iron and manganese was used. The ecological stability of bio-filter was investigated from 3 aspects: iron and manganese removal efficiency, micro-ecological characteristics and the quantity distribution of dominant bacteria. The results indicated that, the bio-filter held strong antishock loading capability, when the system was operated at high filtration rate (10-13.9 m/h) and high manganese concentration (3.5-4.5 mg/L), a removal rate more than 98.9% of iron and manganese was achieved. Iron and manganese oxidizing bacteria are the dominant microflora in biological filtering layer, they not only adhere on filter sand materials (4.3 x 10(6) MPN/mL) to form compact biofilm, but also exist among filter materials void (6.5 x 10(6) MPN/mL) to form suspended flocs, which is very important to complete removal of iron and manganese. In the past 5 years, the bio-filter realized a continuous and stable operation and kept a high removal efficiency of iron and manganese without adding any nutrients.

  12. 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.

  13. Photomicrobial fuel cell (PFC) for simultaneous organic carbon, nutrients removal and energy production

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Safa, Jafar; Angelidaki, Irini

    2014-01-01

    A sediment-type photomicrobial fuel cell (PFC), based on the synergistic interaction between microalgae (Chlorella vulgaris) and electrochemically active bacteria, was developed to remove carbon and nutrients from wastewater, and produce electricity and algal biomass simultaneously. Under...... illumination, stable power density of 68±5 mW/m2 and biomass of 0.56±0.02 g/L were generated at initial algae concentration of 3.5 g/L. Accordingly, the removal efficiency of organic carbon, nitrogen and phosphorus was 99.6%, 87.6% and 69.8%, respectively. Mass balance analysis suggested the main removal...... mechanism of nitrogen and phosphorus was algae biomass uptake (75% and 93%, respectively), while nitrification and denitrification process contributed to part of nitrogen removal (22%). In addition, the effect of illumination period on the performance of PFC was investigated. Except notable fluctuation...

  14. Nutrient content of certain crop residues and possible losses with removal. Appendices A-H

    Energy Technology Data Exchange (ETDEWEB)

    Clambey, G.

    1978-12-01

    The following are included: nutrient content of certain crop residues and possible losses with removal, biomass distribution and availability, biomass equipment survey and evaluation, condition of present municipal power plant, fluidized bed burners, heat balances, selection of best alternate solution for burning biomass, summary and conclusions of potential for oil sunflower production and processing in North Dakota, and a proposed amendment to a DOE grant. (MHR)

  15. Role of extracellular exopolymers on biological phosphorus removal

    Institute of Scientific and Technical Information of China (English)

    LIU Ya-nan; XUE Gang; YU Shui-li; ZHAO Fang-bo

    2006-01-01

    Three sequencing batch reactors supplied with different carbon sources were investigated. The system supplied with glucose gained the best enhanced biological phosphorus removal although all of the three reactors were seeded from the same sludge. With the measurement of poly-β-hydroxyalkanoate (PHA) concentration, phosphorus content in sludge and extracellular exopolymers (EPS) with scanning electron microscopy (SEM) combined with energy dispersive spectrometry (EDS), it was found that the biosorption effect of EPS played an important role in phosphorus removal and that the amount of PHA at the end of anaerobic phase was not the only key factor to determine the following phosphorus removal efficiency.

  16. Life-Cycle Assessment of Advanced Nutrient Removal Technologies for Wastewater Treatment.

    Science.gov (United States)

    Rahman, Sheikh M; Eckelman, Matthew J; Onnis-Hayden, Annalisa; Gu, April Z

    2016-03-15

    Advanced nutrient removal processes, while improving the water quality of the receiving water body, can also produce indirect environmental and health impacts associated with increases in usage of energy, chemicals, and other material resources. The present study evaluated three levels of treatment for nutrient removal (N and P) using 27 representative treatment process configurations. Impacts were assessed across multiple environmental and health impacts using life-cycle assessment (LCA) following the Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts (TRACI) impact-assessment method. Results show that advanced technologies that achieve high-level nutrient removal significantly decreased local eutrophication potential, while chemicals and electricity use for these advanced treatments, particularly multistage enhanced tertiary processes and reverse osmosis, simultaneously increased eutrophication indirectly and contributed to other potential environmental and health impacts including human and ecotoxicity, global warming potential, ozone depletion, and acidification. Average eutrophication potential can be reduced by about 70% when Level 2 (TN = 3 mg/L; TP = 0.1 mg/L) treatments are employed instead of Level 1 (TN = 8 mg/L; TP = 1 mg/L), but the implementation of more advanced tertiary processes for Level 3 (TN = 1 mg/L; TP = 0.01 mg/L) treatment may only lead to an additional 15% net reduction in life-cycle eutrophication potential. PMID:26871301

  17. Nutrient removal and lipid production by Coelastrella sp. in anaerobically and aerobically treated swine wastewater.

    Science.gov (United States)

    Luo, Le; He, Huijun; Yang, Chunping; Wen, Shan; Zeng, Guangming; Wu, Mengjie; Zhou, Zili; Lou, Wei

    2016-09-01

    Coelastrella sp. QY01, a microalgae species isolated from a local pond, was identified and used for the treatment of anaerobically and aerobically treated swine wastewater (AnATSW). Microalgal growth characteristics, nutrient removal and lipid accumulation of QY01 cultivated in the initial concentration of AnATSW ranged from 63 to 319mg NH3-N/L were examined. The specific growth rate of QY01 cultivated in cultures ranged from 0.269 to 0.325day(-1) with a biomass productivity from 42.77 to 57.46mgL(-1)day(-1). Removal rates for NH3-N, TP and inorganic carbon in AnATSW at the various nutrient concentrations ranged from 90% to 100%, from 90% to 100% and from 74% to 78%, respectively. The lipid content of QY01 ranged from 22.4% to 24.8%. The lipid productivity was positive correlation with the biomass productivity. 40% AnATSW was optimal for QY01 cultivation, in which nutrient removal and productivity of biomass and lipid were maximized. PMID:27236400

  18. Influence of wastewater composition on nutrient removal behaviors in the new anaerobic-anoxic/nitrifying/induced crystallization process.

    Science.gov (United States)

    Shi, Jing; Lu, Xiwu; Yu, Ran; Gu, Qian; Zhou, Yi

    2014-01-01

    In this study, the new anaerobic-anoxic/nitrifying/induced crystallization (A2N-IC) system was compared with anaerobic-anoxic/nitrifying (A2N) process to investigate nutrient removal performance under different influent COD and ammonia concentrations. Ammonia and COD removal rates were very stable in both processes, which were maintained at 84.9% and 86.6% when the influent ammonia varied from 30 mg L(-1) to 45 mg L(-1) and COD ranged from 250 mg L(-1) to 300 mg L(-1). The effluent phosphorus always maintained below 0.2 mg L(-1) in A2N-IC, whereas in A2N the effluent phosphorus concentration was 0.4-1.7 mg L(-1), demonstrating that A2N-IC is suitable to apply in a broader influent COD and ammonia concentration range. Under higher influent COD (300 mg L(-1)) or lower ammonia conditions (30 mg L(-1)), the main function of chemical induced crystallization was to coordinate better nutrient ratio for anoxic phosphorus uptake, whereas under high phosphorus concentration, it was to reduce phosphorus loading for biological system. Under the similar influent wastewater compositions, phosphorus release amounts were always lower in A2N-IC. To clarify the decrease procedure of phosphorus release in the A2N-IC, the equilibrium between chemical phosphorus removal and biological phosphorus removal in A2N-IC was analyzed by mass balance equations. During the long-term experiment, some undesirable phenomena were observed: the declining nitrification in post-aerobic tank and calcium phosphorus precipitation in the anaerobic tank. The reasons were analyzed; furthermore, the corresponding improvements were proposed. Nitrification effect could be enhanced in the post-aerobic tank, therefore ammonia removal rate could be increased; and biologically induced phosphorus precipitation could be inhibited by controlling pH at the anaerobic stage, so the phosphorus release and recovery could be improved. PMID:24596502

  19. Protozoan biomass relation to nutrient and chemical oxygen demand removal in activated sludge mixed liquor.

    Science.gov (United States)

    Akpor, Oghenerobor B; Momba, Maggy N B; Okonkwo, Jonathan O

    2008-08-01

    The relationship between biomass concentration to nutrient and chemical oxygen demand (COD) removal in mixed liquor supplemented with sodium acetate was investigated, using three protozoan isolates and three different initial biomass concentrations (10(1), 10(2) and 10(3) cells/mL). The study was carried out in a shaking flask environment at a shaking speed of 100 rpm for 96 h at 25 degrees C. Aliquot samples were taken periodically for the determination of phosphate, nitrate, COD and dissolved oxygen, using standard methods. The results revealed remarkable phosphate removal of 82-95% at biomass concentration of 10(3)cells/mL. A high nitrate removal of over 87% was observed at all initial biomass concentration in mixed liquor. There was an observed COD increase of over 50% in mixed liquor in at the end of 96-h incubation and this was irrespective of initial biomass concentration used for inoculation. The study shows the trend in nutrient and COD removal at different biomass concentrations of the test isolates in mixed liquor.

  20. Nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization without chemical additions

    Energy Technology Data Exchange (ETDEWEB)

    Song Yonghui, E-mail: songyh@craes.org.cn [Chinese Research Academy of Environmental Sciences, Dayangfang 8, Anwai Beiyuan, Beijing 100012 (China); College of Water Science, Beijing Normal University, Xinjiekou Wai Street 19, Beijing 100875 (China); Qiu Guanglei; Yuan Peng [Chinese Research Academy of Environmental Sciences, Dayangfang 8, Anwai Beiyuan, Beijing 100012 (China); College of Water Science, Beijing Normal University, Xinjiekou Wai Street 19, Beijing 100875 (China); Cui Xiaoyu; Peng Jianfeng; Zeng Ping; Duan Liang; Xiang Liancheng; Qian Feng [Chinese Research Academy of Environmental Sciences, Dayangfang 8, Anwai Beiyuan, Beijing 100012 (China)

    2011-06-15

    Anaerobically digested swine wastewater contains high concentrations of phosphorus (P) and nitrogen (N). A pilot-scale experiment was carried out for nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization. In the pilot plant, a sequencing batch reactor (SBR) and a continuous-flow reactor with struvite accumulation devices were designed and employed. The wastewater pH value was increased by CO{sub 2} stripping, and the struvite crystallization process was performed without alkali and Mg{sup 2+} additions. Results of the long-term operation of the system showed that, both reactors provided up to 85% P removal and recovery over wide ranges of aeration times (1.0-4.0 h), hydraulic retention times (HRT) (6.0-15.0 h) and temperatures (0-29.5{sup Degree-Sign }C ) for an extended period of 247 d, in which approximate 30% of P was recovered by the struvite accumulation devices. However, 40-90% of NH{sub 4}{sup +}-N removed was through air stripping instead of being immobilized in the recovered solids. The recovered products were detected and analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD) and chemical methods, which were proved to be struvite with purity of more than 90%. This work demonstrated the feasibility and effects of nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization without chemical additions.

  1. A novel control strategy for efficient biological phosphorus removal with carbon-limited wastewaters.

    Science.gov (United States)

    Guerrero, Javier; Guisasola, Albert; Baeza, Juan A

    2014-01-01

    This work shows the development and the in silico evaluation of a novel control strategy aiming at successful biological phosphorus removal in a wastewater treatment plant operating in an A(2)/O configuration with carbon-limited influent. The principle of this novel approach is that the phosphorus in the effluent can be controlled with the nitrate setpoint in the anoxic reactor as manipulated variable. The theoretical background behind this control strategy is that reducing nitrate entrance to the anoxic reactor would result in more organic matter available for biological phosphorus removal. Thus, phosphorus removal would be enhanced at the expense of increasing nitrate in the effluent (but always below legal limits). The work shows the control development, tuning and performance in comparison to open-loop conditions and to two other conventional control strategies for phosphorus removal based on organic matter and metal addition. It is shown that the novel proposed strategy achieves positive nutrient removal results with similar operational costs to the other control strategies and open-loop operation. PMID:25116500

  2. The Potential Role of Urban Forests in Removing Nutrients from Stormwater.

    Science.gov (United States)

    Denman, E C; May, P B; Moore, G M

    2016-01-01

    Biofiltration systems can be used to improve the quality of stormwater by treating runoff using plants grown in a moderately permeable soil. Most biofilters use herbaceous species, but in highly urbanized locations, such as streets, trees may be a more suitable vegetation. Biofilters that use urban woody vegetation are less studied. This experiment investigated the use of four street tree species [ Schauer, (R. Br.) Peter G. Wilson & J.T. Waterh., (Sm.) Colvill ex Sweet, and L.] and an unplanted control in model biofilters. All four tree species are used in urban landscapes in southern Australia and were chosen to investigate potential species differences in biofiltration systems. The trees were grown in mesocosms as a randomized block factorial design in soils with three saturated hydraulic conductivity rates (4, 95, and 170 mm h). The trees were regularly flooded with mains water (tap water) or artificial stormwater. Tree growth and nutrient removal performance of the systems were investigated over 13 mo. All four species grew well in all three soils, including one chosen for its low, and potentially growth-limiting, drainage rate. Tree growth increased significantly, except for , when flooded with stormwater. Unplanted controls were a source of nutrients; however, the presence of trees reduced oxidized nitrogen and filterable reactive phosphorus concentrations in leachate. There was little effect of species on the removal of nutrients from stormwater. Trees have the potential to be effective elements in urban biofiltration systems, but further field-level evaluation of these systems is required to fully assess this potential.

  3. Biological phosphorus and nitrogen removal in a single sludge system

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Hans

    1996-05-01

    The primary aim of this thesis was to investigate the process stability of a single sludge activated system designed for the combined operation of enhanced biological phosphorus removal (EBPR) and nitrogen removal. A pilot plant at the Sjoelunda wastewater treatment plant in Malmoe, Sweden, has formed the basis for the investigation. The pilot plant study showed that the concentration of total phosphorus on average was low in the effluent, below 0.5 mg P/l. Simultaneously with the highest concentrations of phosphorus in the effluent, the lowest COD/P ratios in the effluent were recorded. A recurrent pattern of high concentrations of phosphorus was observed every year in July, which is the industrial holiday month in Sweden. Other instances of increased phosphorus concentrations in the secondary effluent illustrate the effect of prolonged periods of rain. Increasing flow rates due to rain lead to a dilution and a change in the composition of the COD in the influent wastewater. The COD/P and VFA/P ratios decrease with decreasing concentrations of COD. It was also shown that high removal ratios of both nitrogen and phosphorus during long periods are possible. The nitrogen removal was stable during the whole investigated period, whereas the phosphorus removal was unstable during prolonged periods with low concentrations of COD in the influent water. The combined biological phosphorus and nitrogen removal process implies that during these periods the risk of recirculating nitrate to the anaerobic reactor increases. Such a recirculation both stabilizes the nitrogen removal and withdraws some of the readily degradable organic material from the bio-P bacteria. The main conclusion of this study is that a phosphorus limited EBPR process can cope with the day to day variations, but occasionally, measures have to be taken if the demands for phosphorus removal are stringent. 49 refs, 8 figs, 1 tab

  4. Removal of geosmin and 2-methylisoborneol by biological filtration.

    Science.gov (United States)

    Elhadi, S L N; Huck, P M; Slawson, R M

    2004-01-01

    The quality of drinking water is sometimes diminished by the presence of certain compounds that can impart particular tastes or odours. One of the most common and problematic types of taste and odour is the earthy/musty odour produced by geosmin (trans-1, 10-dimethyl-trans-9-decalol) and MIB (2-methylisoborneol). Taste and odour treatment processes including powdered activated carbon, and oxidation using chlorine, chloramines, potassium permanganate, and sometimes even ozone are largely ineffective for reducing these compounds to below their odour threshold concentration levels. Ozonation followed by biological filtration, however, has the potential to provide effective treatment. Ozone provides partial removal of geosmin and MIB but also creates other compounds more amenable to biodegradation and potentially undesirable biological instability. Subsequent biofiltration can remove residual geosmin and MIB in addition to removing these other biodegradable compounds. Bench scale experiments were conducted using two parallel filter columns containing fresh and exhausted granular activated carbon (GAC) media and sand. Source water consisted of dechlorinated tap water to which geosmin and MIB were added, as well as, a cocktail of easily biodegradable organic matter (i.e. typical ozonation by-products) in order to simulate water that had been subjected to ozonation prior to filtration. Using fresh GAC, total removals of geosmin ranged from 76 to 100% and total MIB removals ranged from 47% to 100%. The exhausted GAC initially removed less geosmin and MIB but removals increased over time. Overall the results of these experiments are encouraging for the use of biofiltration following ozonation as a means of geosmin and MIB removal. These results provide important information with respect to the role biofilters play during their startup phase in the reduction of these particular compounds. In addition, the results demonstrate the potential biofilters have in responding to

  5. Iron removal from milk and other nutrient media with a chelating resin.

    Science.gov (United States)

    Feng, M; van der Does, L; Bantjes, A; de Groote, J M

    1995-01-01

    A water-insoluble iron(III)-chelating resin was used to study iron removal from milk and other nutrient media. Seventy to 85% of the iron could be removed from wine and beer with the resin, which was a crosslinked copolymer of 1-(beta-acrylamidoethyl)-3-hydroxy-2-methyl-4(1H)- pyridinone and N,N-dimethylacrylamide. Iron removal from milk was dependent on the pH of milk and on the concentration of soluble chelators added. Under the same conditions as used for the removal of iron from wine and beer, only 11 to 19% of the iron could be removed from milk. However, in combination with water-soluble chelators, the resin removed 60 to 75% of the iron from the milk. Preliminary results showed that the growth of spores of Clostridium tyrobutyricum in the treated milk was reduced. Moreover, addition of the resin and sodium bicarbonate to the milk completely inhibited the growth of the spores. PMID:7738259

  6. Efficiency and kinetic modeling of removal of nutrients and organic matter from a full-scale constructed wetland in Qasre-Shirin, Iran

    Directory of Open Access Journals (Sweden)

    Abdolmajid Gholizadeh

    2015-09-01

    Full Text Available Background: This study assessed the removal of organic material and nutrients from full-scale subsurface flow (SSF constructed wetlands (CWs followed by anaerobic stabilization ponds under environmental conditions. Methods: The effluents were distributed evenly in 12 reed beds. Samples were taken twice monthly for a total of 6 months from several points in the wetland. Biochemical oxygen demand (BOD, chemical oxygen demand (COD, total suspended solids (TSS, and nutrient removal from the system and the longitudinal effect of the reed beds for removal of pollutions were determined. A full-scale model of flow, BOD, and nutrients in SSF in the CWs is presented. Results: The flow rate and concentrations of parameters indicated that removal of organic matter and nutrients in the cold months decreased rather than in the hot months, as expected. The removal efficiency for BOD, COD, and TSS and the strongest biological interactions showed no uniform trends. The beds showed the highest removal rates in the first few meters of bed. The hybrid Monod-Plug flow regime and the Stover-Kincannon models showed the best fit for the kinetics of the processes. Umax in the Stover-Kincannon model was 3.64 mg/l.d for nitrogen and 0.24 mg/l.d for phosphorus. These values are very low, which indicates lower consumption and inefficiency of the system for removing nitrogen and phosphorus. Conclusion: It can be concluded that the SSF in CWs are able to treat average wastewater as effectively as common mechanical systems at lower cost.

  7. High-latitude controls of thermocline nutrients and low latitude biological productivity.

    Science.gov (United States)

    Sarmiento, J L; Gruber, N; Brzezinski, M A; Dunne, J P

    2004-01-01

    The ocean's biological pump strips nutrients out of the surface waters and exports them into the thermocline and deep waters. If there were no return path of nutrients from deep waters, the biological pump would eventually deplete the surface waters and thermocline of nutrients; surface biological productivity would plummet. Here we make use of the combined distributions of silicic acid and nitrate to trace the main nutrient return path from deep waters by upwelling in the Southern Ocean and subsequent entrainment into subantarctic mode water. We show that the subantarctic mode water, which spreads throughout the entire Southern Hemisphere and North Atlantic Ocean, is the main source of nutrients for the thermocline. We also find that an additional return path exists in the northwest corner of the Pacific Ocean, where enhanced vertical mixing, perhaps driven by tides, brings abyssal nutrients to the surface and supplies them to the thermocline of the North Pacific. Our analysis has important implications for our understanding of large-scale controls on the nature and magnitude of low-latitude biological productivity and its sensitivity to climate change.

  8. Kinetic start-up performance of two large treatment plants for nutrient removal

    DEFF Research Database (Denmark)

    Haarbo, A.; Harremoës, Poul; Thirsing, C.

    2001-01-01

    of the start-up of the two full-scale plants with the main emphasis laid on the kinetic performance in relation to the information achieved from the pilot tests. The results showed that the start-up of the full scale plants proceeded with great accuracy as expected from the investigations. Accordingly......In 1987 an action plan was passed in the Danish Parliament demanding a considerable reduction of the discharge of nutrients to the aquatic environment in Denmark. Consequently, the two largest wastewater treatment plants in the Copenhagen area had to be upgraded to include nutrient removal....... For more than 8 years an extensive effort has been made to determine an optimum solution for this upgrading from a technical and financial point of view. The work included six years of comprehensive pilot plant investigations with the aim of thoroughly studying and interpreting the kinetics...

  9. Mixed Wastewater Coupled with CO2 for Microalgae Culturing and Nutrient Removal.

    Directory of Open Access Journals (Sweden)

    Lili Yao

    Full Text Available Biomass, nutrient removal capacity, lipid productivity and morphological changes of Chlorella sorokiniana and Desmodesmus communis were investigated in mixed wastewaters with different CO2 concentrations. Under optimal condition, which was 1:3 ratio of swine wastewater to second treated municipal wastewater with 5% CO2, the maximum biomass concentrations were 1.22 g L-1 and 0.84 g L-1 for C. sorokiniana and D. communis, respectively. Almost all of the ammonia and phosphorus were removed, the removal rates of total nitrogen were 88.05% for C. sorokiniana and 83.18% for D. communis. Lipid content reached 17.04% for C. sorokiniana and 20.37% for D. communis after 10 days culture. CO2 aeration increased intracellular particle numbers of both microalgae and made D. communis tend to be solitary. The research suggested the aeration of CO2 improve the tolerance of microalgae to high concentration of NH4-N, and nutrient excess stress could induce lipid accumulation of microalgae.

  10. Microbial population analysis of nutrient removal-related organisms in membrane bioreactors

    NARCIS (Netherlands)

    Silva, A.F.; Carvalho, G.; Oehmen, A.; Lousada-Ferreira, M.; Van Nieuwenhuijzen, A.; Reis, M.A.M.; Crespo, M.T.B.

    2012-01-01

    Membrane bioreactors (MBR) are an important and increasingly implemented wastewater treatment technology, which are operated at low food to microorganism ratios (F/M) and retain slow-growing organisms. Enhanced biological phosphorus removal (EBPR)-related organisms grow slower than ordinary heterotr

  11. Identification of active denitrifiers in full-scale nutrient removal wastewater treatment systems

    DEFF Research Database (Denmark)

    McIlroy, Simon Jon; Szyszka, Anna; Starnawski, Piotr Marian;

    2016-01-01

    in combination with microautoradiography (MAR)-fluorescence in situ hybridisation (FISH) to identify the active denitrifiers in a full-scale WWTP with biological N and P removal. Recognising that a range of carbon sources likely drive denitrification, a fully 13 C-labelled complex substrate was used for SIP...

  12. The effect of light supply on microalgal growth, CO2 uptake and nutrient removal from wastewater

    International Nuclear Information System (INIS)

    Highlights: • Effect of irradiance and light:dark ratio on microalgal growth was analysed. • Microalgal growth, CO2 capture, nitrogen and phosphorus uptake were evaluated. • Higher irradiances and light periods supported higher growth and CO2 uptake rates. • All the studied microalgal strains have shown high nitrogen removal efficiencies. • The highest phosphorus removal efficiency was 67.6%. - Abstract: Microalgal based biofuels have been reported as an attractive alternative for fossil fuels, since they constitute a renewable energy source that reduces greenhouse gas emissions to the atmosphere. However, producing biofuels from microalgae is still not economically viable. Therefore, the integration of biofuel production with other microalgal applications, such as CO2 capture and nutrient removal from wastewaters, would reduce the microalgal production costs (and the environmental impact of cultures), increasing the economic viability of the whole process. Additionally, producing biofuels from microalgae strongly depends on microalgal strain and culture conditions. This study evaluates the effect of culture conditions, namely light irradiance (36, 60, 120 and 180 μE m−2 s−1) and light:dark ratio (10:14, 14:10 and 24:0), on microalgal growth, atmospheric CO2 uptake and nutrient (nitrogen and phosphorous) removal from culture medium. Four different microalgal strains, Chlorella vulgaris, Pseudokirchneriella subcapitata, Synechocystis salina and Microcystis aeruginosa, were studied to ascertain the most advantageous regarding the referred applications. This study has shown that higher light irradiance values and light periods resulted in higher specific growth rates and CO2 uptake rates. C. vulgaris presented the highest specific growth rate and CO2 uptake rate: 1.190 ± 0.041 d−1 and 0.471 ± 0.047 gCO2 L−1 d−1, respectively. All the strains have shown high nitrogen removal efficiencies, reaching 100% removal percentages in cultures with higher

  13. Assessment of the nutrient removal effectiveness of floating treatment wetlands applied to urban retention ponds.

    Science.gov (United States)

    Wang, Chih-Yu; Sample, David J

    2014-05-01

    The application of floating treatment wetlands (FTWs) in point and non-point source pollution control has received much attention recently. Although the potential of this emerging technology is supported by various studies, quantifying FTW performance in urban retention ponds remains elusive due to significant research gaps. Actual urban retention pond water was utilized in this mesocosm study to evaluate phosphorus and nitrogen removal efficiency of FTWs. Multiple treatments were used to investigate the contribution of each component in the FTW system with a seven-day retention time. The four treatments included a control, floating mat, pickerelweed (Pontederia cordata L.), and softstem bulrush (Schoenoplectus tabernaemontani). The water samples collected on Day 0 (initial) and 7 were analyzed for total phosphorus (TP), total particulate phosphorus, orthophosphate, total nitrogen (TN), organic nitrogen, ammonia nitrogen, nitrate-nitrite nitrogen, and chlorophyll-a. Statistical tests were used to evaluate the differences between the four treatments. The effects of temperature on TP and TN removal rates of the FTWs were described by the modified Arrhenius equation. Our results indicated that all three FTW designs, planted and unplanted floating mats, could significantly improve phosphorus and nitrogen removal efficiency (%, E-TP and E-TN) compared to the control treatment during the growing season, i.e., May through August. The E-TP and E-TN was enhanced by 8.2% and 18.2% in the FTW treatments planted with the pickerelweed and softstem bulrush, respectively. Organic matter decomposition was likely to be the primary contributor of nutrient removal by FTWs in urban retention ponds. Such a mechanism is fostered by microbes within the attached biofilms on the floating mats and plant root surfaces. Among the results of the four treatments, the FTWs planted with pickerelweed had the highest E-TP, and behaved similarly with the other two FTW treatments for nitrogen removal

  14. Nutrient removal using biosorption activated media: preliminary biogeochemical assessment of an innovative stormwater infiltration basin

    Science.gov (United States)

    O'Reilly, Andrew M.; Wanielista, Martin P.; Chang, Ni-Bin; Xuan, Zhemin; Harris, Willie G.

    2012-01-01

    Soil beneath a stormwater infiltration basin receiving runoff from a 22.7 ha predominantly residential watershed in central Florida, USA, was amended using biosorption activated media (BAM) to study the effectiveness of this technology in reducing inputs of nitrogen and phosphorus to groundwater. The functionalized soil amendment BAM consists of a 1.0:1.9:4.1 mixture (by volume) of tire crumb (to increase sorption capacity), silt and clay (to increase soil moisture retention), and sand (to promote sufficient infiltration), which was applied to develop a prototype stormwater infiltration basin utilizing nutrient reduction and flood control sub-basins. Comparison of nitrate/chloride (NO3-/Cl-) ratios for the shallow groundwater indicate that prior to using BAM, NO3- concentrations were substantially influenced by nitrification or variations in NO3- input. In contrast, for the prototype basin utilizing BAM, NO3-/Cl- ratios indicate minor nitrification and NO3- losses with the exception of one summer sample that indicated a 45% loss. Biogeochemical indicators (denitrifier activity derived from real-time polymerase chain reaction and variations in major ions, nutrients, dissolved and soil gases, and stable isotopes) suggest NO3- losses are primarily attributable to denitrification, whereas dissimilatory nitrate reduction to ammonium is a minor process. Denitrification was likely occurring intermittently in anoxic microsites in the unsaturated zone, which was enhanced by increased soil moisture within the BAM layer and resultant reductions in surface/subsurface oxygen exchange that produced conditions conducive to increased denitrifier activity. Concentrations of total dissolved phosphorus and orthophosphate (PO43-) were reduced by more than 70% in unsaturated zone soil water, with the largest decreases in the BAM layer where sorption was the most likely mechanism for removal. Post-BAM PO43-/Cl- ratios for shallow groundwater indicate predominantly minor increases and

  15. Practice of High Concentration Sludge for Efficient Nutrient Removal from Municipal Sewage

    Institute of Scientific and Technical Information of China (English)

    LI Ang; ZHANG Yan-qiu; LI Yan

    2010-01-01

    ECOSUNIDE is a new activated sludge process based on the sludge concentration optimization theory.With it,we carried out a high sludge concentration by changing influent mode and distributing carbon source in a reasonable way,which can improve the ecological superiority of nitrification and denitrification for the growth of phosphorous accumulating organisms(PAOs)and nitrifiers and raised the nutrient removal efficiency of municipal sewage treatment plants.In 2007,we adopted this technique in Linyi Sewage Treatment Plant in Shandong Province,China.After the reconstruction,we achieved the high efficiency of nutrient removal with low investment under the dynamic load of the secondary sewage treatment plant.The effluent water qualities meet the class I-A criteria specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB 18918-2002)and the rest effluent indexes meet the class I-B criteria.Besides, we have above 20% operating cost cut by stopping the internal reflux without power charge increased and any new pool structures built.

  16. Identification and Control of Nutrient Removing Processes in Wastewater Treatment Plants

    DEFF Research Database (Denmark)

    Nielsen, Marinus K.; Madsen, Henrik; Carstensen, Niels Jacob

    1994-01-01

    Today the use of on-line control for wastewater treatment plants is very low. A main reason is the lack of quality of the data, and the fact that more sophisticated control strategies must be based on a model of the dynamics of the biological processes. This paper discusses the historical reasons...... for the limited use of modern control strategies for wastewater treatment plants. Today, however, on-line nutrient sensors are more reliable. In the present context the use of on-line monitored values of ammonia, nitrate and phosphate from a full scale plant are used as the background for discussing...

  17. Impacts of variable pH on stability and nutrient removal efficiency of aerobic granular sludge.

    Science.gov (United States)

    Lashkarizadeh, Monireh; Munz, Giulio; Oleszkiewicz, Jan A

    2016-01-01

    The impact of pH variation on aerobic granular sludge stability and performance was investigated. A 9-day alkaline (pH=9) and acidic (pH=6) pH shocks were imposed on mature granules with simultaneous chemical oxygen demand (COD), nitrogen and phosphorus removal. The imposed alkaline pH shock (pH 9) reduced nitrogen and phosphorus removal efficiency from 88% and 98% to 66% and 50%, respectively, with no further recovery. However, acidic pH shock (pH 6) did not have a major impact on nutrient removal and the removal efficiencies recovered to their initial values after 3 days of operation under the new pH condition. Operating the reactors under alkaline pH induced granules breakage and resulted in an increased solids concentration in the effluent and a significant decrease in the size of the bio-particles, while acidic pH did not have significant impacts on granules stability. Changes in chemical structure and composition of extracellular polymeric substances (EPS) matrix were suggested as the main factors inducing granules instability under high pH. PMID:26744935

  18. Including Life Cycle Assessment for decision-making in controlling wastewater nutrient removal systems.

    Science.gov (United States)

    Corominas, Lluís; Larsen, Henrik F; Flores-Alsina, Xavier; Vanrolleghem, Peter A

    2013-10-15

    This paper focuses on the use of Life Cycle Assessment (LCA) to evaluate the performance of seventeen control strategies in wastewater treatment plants (WWTPs). It tackles the importance of using site-specific factors for nutrient enrichment when decision-makers have to select best operating strategies. Therefore, the LCA evaluation is repeated for three different scenarios depending on the limitation of nitrogen (N), phosphorus (P), or both, when evaluating the nutrient enrichment impact in water bodies. The LCA results indicate that for treated effluent discharged into N-deficient aquatic systems (e.g. open coastal areas) the most eco-friendly strategies differ from the ones dealing with discharging into P-deficient (e.g. lakes and rivers) and N&P-deficient systems (e.g. coastal zones). More particularly, the results suggest that strategies that promote increased nutrient removal and/or energy savings present an environmental benefit for N&P and P-deficient systems. This is not the case when addressing N-deficient systems for which the use of chemicals (even for improving N removal efficiencies) is not always beneficial for the environment. A sensitivity analysis on using weighting of the impact categories is conducted to assess how value choices (policy decisions) may affect the management of WWTPs. For the scenarios with only N-limitation, the LCA-based ranking of the control strategies is sensitive to the choice of weighting factors, whereas this is not the case for N&P or P-deficient aquatic systems.

  19. Nutrients' removal from aquaculture wastewater using the macroalgae Gracilaria birdiae

    Energy Technology Data Exchange (ETDEWEB)

    Marinho-Soriano, E.; Nunes, S.O.; Carneiro, M.A.A.; Pereira, D.C. [Universidade Federal do Rio Grande do Norte, Depto. de Oceanografia e Limnologia, Via Costeira, Praia de Mae Luiza, s/n, Natal, RN 59014-100 (Brazil)

    2009-02-15

    Intensive aquaculture releases large amount of nutrients into aquatic ecosystems and can lead to eutrophication of coastal waters. Studies conducted in aquaculture systems have demonstrated that the seaweeds are efficient in reducing nutrients and at the same time provides extra income, when species of economic importance are used. This study was conducted to evaluate whether Gracilaria birdiae could be cultivated efficiently for the production of useful algal biomass and removal of nutrients from shrimp pond effluents. The results obtained showed a gradual increase in biomass and relative growth rate (RGR) over the experimental period. Mean RGR between the weeks varied significantly (p < 0.01), reaching a maximum of 3.6 {+-} 0.35% d{sup -1} and a minimum of 1.6 {+-} 0.52% d{sup -1}. The mean for the whole period was 2.6% d{sup -1}. The biofiltration capacity of G. birdiae was confirmed by the significantly reduced concentration of the three nutrients analyzed (PO{sub 4}{sup 3-}, NH{sub 4}{sup +} and NO{sub 3}{sup -}) over the study period. The concentration of PO{sub 4}{sup 3-} decreased by 93.5%, NH{sub 4}{sup +} by 34% and NO{sub 3}{sup -} by 100% after the 4-week experimental period. The results obtained in this study indicated that G. birdiae can be used in aquaculture systems as a biofilter. In addition, the macroalgae biomass produced offers alternative source of raw material for the extraction of the phycocolloid agar, human food and animal feed. (author)

  20. Sample validity in biological trace element and organic nutrient research studies

    International Nuclear Information System (INIS)

    The state of the art of the biological trace element investigations is overviewed. Questions of biological validity, such as the influence of the 'status of sampling' of human subjects on the concentrations of selected elements are studied. Analytical validity problems, e.g. stability of Cd, Hg and Pb concentration in selected specimens, stability of selected organic nutrients in NBS SRMs, etc. are also discussed. Finally, it is concluded that the development of new biological reference materials should take into account the multidisciplinary demands of biological trace element investigations. (author) 20 refs.; 6 tables

  1. Nutrient removal using biosorption activated media: Preliminary biogeochemical assessment of an innovative stormwater infiltration basin

    Energy Technology Data Exchange (ETDEWEB)

    O' Reilly, Andrew M., E-mail: aoreilly@usgs.gov [U.S. Geological Survey, Florida Water Science Center, 12703 Research Pkwy, Orlando, FL 32826 (United States); Wanielista, Martin P., E-mail: Martin.Wanielista@ucf.edu [University of Central Florida, Water Research Center and Stormwater Management Academy, 4000 Central Florida Blvd, Building 91, Suite 442, Orlando, FL 32816 (United States); Chang, Ni-Bin, E-mail: Ni-bin.Chang@ucf.edu [University of Central Florida, Department of Civil, Environmental, and Construction Engineering, 4000 Central Florida Blvd, Building 91, Suite 442, Orlando, FL 32816 (United States); Xuan, Zhemin, E-mail: zheminxuan@gmail.com [University of Central Florida, Department of Civil, Environmental, and Construction Engineering, 4000 Central Florida Blvd, Building 91, Suite 442, Orlando, FL 32816 (United States); Harris, Willie G., E-mail: apatite@ufl.edu [University of Florida, Soil and Water Science Department, 2169 McCarty Hall, Gainesville, FL 32611 (United States)

    2012-08-15

    for removal. Post-BAM PO{sub 4}{sup 3-}/Cl{sup -} ratios for shallow groundwater indicate predominantly minor increases and decreases in PO{sub 4}{sup 3-} with the exception of one summer sample that indicated a 50% loss. Differences in nutrient variations between the unsaturated zone and shallow groundwater may be the result of the intensity and duration of nutrient removal processes and mixing ratios with water that had undergone little biogeochemical transformation. Observed nitrogen and phosphorus losses demonstrate the potential, as well as the future research needs to improve performance, of the innovative stormwater infiltration basin using BAM for providing passive, economical, stormwater nutrient-treatment technology to support green infrastructure. -- Highlights: Black-Right-Pointing-Pointer New technology to control nutrient leaching beneath stormwater infiltration basins. Black-Right-Pointing-Pointer Integrated nutrient reduction and flood control sub-basins. Black-Right-Pointing-Pointer Biosorption activated media (BAM) promotes sorption and soil moisture retention. Black-Right-Pointing-Pointer Soil moisture retention is key BAM function promoting biogeochemical processes. Black-Right-Pointing-Pointer Documented decreases in nitrogen and phosphorus species.

  2. Removal design report for the 108-F Biological Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    Most of the 100-F facilities were deactivated with the reactor and have since been demolished. Of the dozen or so reactor-related structures, only the 105-F Reactor Building and the 108-F Biology Laboratory remain standing today. The 108-F Biology Laboratory was intended to be used as a facility for the mixing and addition of chemicals used in the treatment of the reactor cooling water. Shortly after F Reactor began operation, it was determined that the facility was not needed for this purpose. In 1949, the building was converted for use as a biological laboratory. In 1962, the lab was expanded by adding a three-story annex to the original four-story structure. The resulting lab had a floor area of approximately 2,883 m{sup 2} (main building and annex) that operated until 1973. The building contained 47 laboratories, a number of small offices, a conference room, administrative section, lunch and locker rooms, and a heavily shielded, high-energy exposure cell. The purpose of this removal design report is to establish the methods of decontamination and decommissioning and the supporting functions associated with facility removal and disposal.

  3. Biological methods of dye removal from textile effluents - A review

    Directory of Open Access Journals (Sweden)

    Archna *

    2012-08-01

    Full Text Available Textile dyes are molecules designed to impart permanent colours to textile fabrics. They pose an environmental problem due to their toxicity and decrease the aesthetic value of water bodies into which they are discharged. Current physico-chemical technologies for dye removal cannot remove all classes of dyes, and two or more technologies are usually combined to achieve satisfactory decolourisation efficiencies. Direct biological treatment using fungi or bacteria can also be employed, but nutritional and physiological requirements of microorganisms put constraints on the applicability of such bioremediation processes. The search for efficient and green oxidation technologies has increased the interest in the use of enzymes to replace the conventional non-biological methods. Among the different existing oxidant enzymes, laccase (benzenediol:oxygen oxidoreductases; EC 1.10.3.2 has been the subject of intensive research in the past few decades due to its low substrate specificity. Enzymatic treatment using laccase can be simpler and much more efficient than the traditional physical or chemical treatments. This paper reviews conventional biological processes as well as  laccase-based processes might replace the traditionally energy intensive and water-consuming chemical treatment operations in the textile industry. Keywords: Dyes, Decolourisation, Green Oxidation, Laccase, Textile industry  

  4. Biological removal of dimethyl sulphide from sea water

    Science.gov (United States)

    Kiene, Ronald P.; Bates, Timothy S.

    1990-06-01

    DIMETHYL sulphide (DMS) is an important sulphur-containing trace gas in the atmosphere. It is present in oceanic surface waters at concentrations sufficient to sustain a considerable net flux of DMS from the oceans to the atmosphere, estimated to comprise nearly half of the global biogenic input of sulphur to the atmosphere1. DMS emitted from the oceans may be a precursor of tropospheric aerosols and of cloud condensation nuclei in the remote marine atmosphere, thereby affecting the Earth's radiative balance and thus its climate2-4. Relatively little is known, however, about the biogeochemical and physical processes that control the concentration of DMS in sea water. Here we present data from incubation experiments, carried out at sea, which show that DMS is removed by microbial activity. In the eastern, tropical Pacific Ocean, DMS turnover is dominated by biological processes, with turnover times for biological DMS removal generally more than ten (3-430) times faster than turnover by ventilation to the atmosphere. Thus biological consumption of DMS seems to be a more important factor than atmospheric exchange in controlling DMS concentrations in the ocean, and hence its flux to the atmosphere. These results have significant implications for climate feedback models involving DMS emissions3, and highlight the importance of the microbial food web in oceanic DMS cycling.

  5. Modified rotating biological contactor for removal of dichloromethane vapours.

    Science.gov (United States)

    Ravi, R; Philip, Ligy; Swaminathan, T

    2015-01-01

    Bioreactors are used for the treatment of waste gas and odour that has gained much acceptance in the recent years to treat volatile organic compounds (VOCs). The different types of bioreactors (biofilter, biotrickling filter and bioscrubber) have been used for waste gas treatment. Each of these reactors has some advantages and some limitations. Though biodegradation is the main process for the removal of the pollutants, the mechanisms of removal and the microbial communities may differ among these bioreactors. Consequently, their performance or removal efficiency may also be different. Clogging of reactor and pressure drop are the main problems. In this study attempts are made to use the principle of rotating biological contactor (RBC) used for wastewater treatment for the removal of VOC. To overcome the above problem the RBC is modified which is suitable for the treatment of VOC (dichloromethane, DCM). DCM is harmful to human health and hazardous to the atmospheric environment. Modified RBC had no clogging problems and no pressure drop. So, it can handle the pollutant load for a longer period of time. A maximum elimination capacity of 25.7 g/m3 h has been achieved in this study for the DCM inlet load of 58 g/m3 h. The average biofilm thickness is 1 mm. The transient behaviour of the modified RBC treating DCM was investigated. The modified RBC is able to handle shutdown, restart and shock loading operations.

  6. Atrazine Removal from Aqueous Solutions using Submerged Biological Aerated Filter

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Baghapour

    2013-06-01

    Full Text Available Atrazine is widely used in the agriculture as an herbicide. Due to its high mobility, Atrazine leaks into the groundwaters, surface waters, and drinking water wells. Many physical and chemical methods have been suggested for removing Atrazine from aquatic environments. However, these methods are very costly, have many performance problems, produce a lot of toxic intermediates which are very harmful and dangerous, and cannot completely mineralize Atrazine. In this study, biodegradation of Atrazine by microbial consortium was evaluated in the aquatic environment. In order to assess the Atrazine removal from the aquatic environment, submerged biological aerated filter (SBAF was fed with synthetic wastewater based on sucrose and Atrazine at different hydraulic retention times (HRTs. The maximum efficiencies for Atrazine and Soluble Chemical Oxygen Demand (SCOD removal were 97.9% and 98.9%, respectively. The study findings showed that Stover-Kincannon model had very good fitness (R2 > 99% in loading Atrazine in the biofilter and by increasing the initial concentration of Atrazine, the removal efficiency increased. Aerobic mixed biofilm culture was observed to be suitable for the treatment of Atrazine from aquatic environment. There was no significant inhibition effect on mixed aerobic microbial consortia. Atrazine degradation depended on the strength of wastewater and the amount of Atrazine in the influent

  7. Atrazine removal from aqueous solutions using submerged biological aerated filter.

    Science.gov (United States)

    Baghapour, Mohammad Ali; Nasseri, Simin; Derakhshan, Zahra

    2013-01-01

    Atrazine is widely used in the agriculture as an herbicide. Due to its high mobility, Atrazine leaks into the groundwaters, surface waters, and drinking water wells. Many physical and chemical methods have been suggested for removing Atrazine from aquatic environments. However, these methods are very costly, have many performance problems, produce a lot of toxic intermediates which are very harmful and dangerous, and cannot completely mineralize Atrazine. In this study, biodegradation of Atrazine by microbial consortium was evaluated in the aquatic environment. In order to assess the Atrazine removal from the aquatic environment, submerged biological aerated filter (SBAF) was fed with synthetic wastewater based on sucrose and Atrazine at different hydraulic retention times (HRTs). The maximum efficiencies for Atrazine and Soluble Chemical Oxygen Demand (SCOD) removal were 97.9% and 98.9%, respectively. The study findings showed that Stover-Kincannon model had very good fitness (R2 > 99%) in loading Atrazine in the biofilter and by increasing the initial concentration of Atrazine, the removal efficiency increased. Aerobic mixed biofilm culture was observed to be suitable for the treatment of Atrazine from aquatic environment. There was no significant inhibition effect on mixed aerobic microbial consortia. Atrazine degradation depended on the strength of wastewater and the amount of Atrazine in the influent. PMID:24499572

  8. Benchmarking Combined Biological Phosphorus and Nitrogen Removal Wastewater Treatment Processes

    DEFF Research Database (Denmark)

    Gernaey, Krist; Jørgensen, Sten Bay

    2004-01-01

    are to a large extent based on the already existing nitrogen removal simulation benchmark. The paper illustrates and motivates the selection of the treatment plant lay-out, the selection of the biological process model, the development of realistic influent disturbance scenarios for dry, rain and storm weather...... resulting from open loop simulations with a dynamic dry weather influent scenario. The influence of the dissolved oxygen set point selection on the nitrate control loop performance observed in the simulations further illustrates the need for a plant-wide optimization approach to reach optimal plant...

  9. Environmental distribution and population biology of Candidatus Accumulibacter, a primary agent of Biological Phosphorus Removal

    OpenAIRE

    Peterson, S. Brook; Warnecke, Falk; Madejska, Julita; McMahon, Katherine D.; Hugenholtz, Philip

    2008-01-01

    Members of the uncultured bacterial genus Candidatus Accumulibacter are capable of intracellular accumulation of inorganic phosphate (Pi) in activated sludge wastewater treatment plants (WWTPs) performing enhanced biological phosphorus removal (EBPR), but were also recently shown to inhabit freshwater and estuarine sediments. Additionally, metagenomic sequencing of two bioreactor cultures enriched in Candidatus Accumulibacter, but housed on separate continents, revealed the potential for glob...

  10. BIOLOGY OF POLYPHOSPHATE-ACCUMULATING BACTERIA INVOLVED IN ENHANCED BIOLOGICAL PHOSPHORUS REMOVAL

    NARCIS (Netherlands)

    KORTSTEE, GJJ; APPELDOORN, KJ; BONTING, CFC; VANNIEL, EWJ; VANVEEN, HW

    1994-01-01

    Recent research on the process of biological phosphorus removal in lab-scale treatment systems has indicated that: (i) the development of an actively polyP-accumulating bacterial community after the introduction of an anaerobic period may take at least 4 months; (ii) up to 80% of all aerobic bacteri

  11. Biological nitrogen removal with enhanced phosphate uptake in a sequencing batch reactor using single sludge system.

    Science.gov (United States)

    Lee, D S; Jeon, C O; Park, J M

    2001-11-01

    Simultaneous biological phosphorus and nitrogen removal with enhanced anoxic phosphate uptake was investigated in an anaerobic-aerobic-anoxic-aerobic sequencing batch reactor ((AO)2 SBR). Significant amounts of phosphorus-accumulation organisms (PAOs) capable of denitrification could be accumulated in a single sludge system coexisting with nitrifiers. The ratio of the anoxic phosphate uptake to the aerobic phosphate uptake capacity was increased from 11% to 64% by introducing an anoxic phase in an anaerobic aerobic SBR. The (AO)2 SBR system showed stable phosphorus and nitrogen removal performance. Average removal efficiencies of TOC, total nitrogen, and phosphorus were 92%, 88%, and 100%, respectively. It was found that nitrite (up to 10 mg NO2(-)-N/l) was not detrimental to the anoxic phosphate uptake and could serve as an electron acceptor like nitrate. In fact, the phosphate uptake rate was even faster in the presence of nitrite as an electron acceptor compared to the presence of nitrate. It was found that on-line sensor values of pH, ORP, and DO were somehow related with the dynamic behaviours of nutrient concentrations (NH4+, NO3-, and PO4(3-)) in the SBR. These on-line sensor values were used as real-time control parameters to adjust the duration of each operational phase in the (AO)2 SBR. The real-time controlled SBR exhibited better performance in the removal of phosphorus and nitrogen than the SBR with fixed-time operation. PMID:12230180

  12. Biological removal of arsenic pollution by soil fungi.

    Science.gov (United States)

    Srivastava, Pankaj Kumar; Vaish, Aradhana; Dwivedi, Sanjay; Chakrabarty, Debasis; Singh, Nandita; Tripathi, Rudra Deo

    2011-05-15

    Fifteen fungal strains were isolated from arsenic contaminated (range 9.45-15.63 mg kg(-1)) agricultural soils from the state of West Bengal, India. Five fungal strains were belonged to the Aspergillus and Trichoderma group each, however, remaining five were identified as the Neocosmospora, Sordaria, Rhizopus, Penicillium and sterile mycelial strain. All these fungal strains were cultivated on medium supplemented with 100, 500, 1000, 5000 and 10,000 mg l(-1) of sodium arsenate. After 30-day cultivation under laboratory conditions, radial growth of these strains was determined and compared with control. Toxicity and tolerance of these strains to arsenate were evaluated on the basis of tolerance index. Out of fifteen, only five fungal strains were found resistant and survived with tolerance index pattern as 0.956 (sterile mycelial strain)>0.311 (Rhizopus sp.)>0.306 (Neocosmospora sp.)>0.212 (Penicillium sp.)>0.189 (Aspergillus sp.) at 10,000 mg l(-1) of arsenate. The arsenic removal efficacy of ten fungal strains, tolerant to 5000 mg l(-1) arsenate, was also assayed under laboratory conditions for 21 days. All these strains were cultivated individually on mycological broth enriched with 10 mg l(-1) of arsenic. The initial and final pH of cultivating medium, fungal biomass and removal of arsenic by each fungal strain were evaluated. Fungal biomass of ten strains removed arsenic biologically from the medium which were ranged from 10.92 to 65.81% depending on fungal species. The flux of biovolatilized arsenic was determined indirectly by estimating the sum of arsenic content in fungal biomass and medium. The mean percent removal as flux of biovolatilized arsenic ranged from 3.71 to 29.86%. The most effective removal of arsenic was observed in the Trichoderma sp., sterile mycelial strain, Neocosmospora sp. and Rhizopus sp. fungal strains. These fungal strains can be effectively used for the bioremediation of arsenic-contaminated agricultural soils.

  13. Neochloris oleoabundans grown on anaerobically digested dairy manure for concomitant nutrient removal and biodiesel feedstock production

    International Nuclear Information System (INIS)

    Microalgae have been investigated as a promising biodiesel feedstock; however, large-scale production is not currently cost-competitive with petroleum diesel, and its environmental impacts have received little attention. Using wastewater to supply nutrients for algal growth obviates synthetic fertilizer use, provides on-site nutrient removal, and reduces greenhouse gas emissions. In this work, anaerobically digested dairy manure was used to grow the oleaginous green alga Neochloris oleoabundans. In batch culture experiments with both synthetic media and anaerobic digester effluent, N. oleoabundans assimilated 90-95% of the initial nitrate and ammonium after 6 d and yielded 10-30% fatty acid methyl esters on a dry weight basis. Cellular lipid content and the N concentration in the growth media were inversely correlated. In addition, the proportion of polyunsaturated fatty acids (i.e. C16:3, C18:2, and C18:3) decreased with N concentration over time while the proportion of C18:1 fatty acid increased. Although N deficiency is likely the primary driver behind lipid accumulation, the influence of culture pH confounded results and requires further study. Other living microorganisms in the digester effluent were not observed to affect algal growth and lipid productivity, though the breakdown of organic nitrogen may have hindered lipid accumulation traditionally achieved through the manipulation of synthetic media. This work highlights the potential for waste-grown mono-algal cultures to produce high quality biodiesel while accomplishing simultaneous wastewater treatment.

  14. Nutrient control of eukaryote cell growth: a systems biology study in yeast

    Directory of Open Access Journals (Sweden)

    Lilley Kathryn S

    2010-05-01

    Full Text Available Abstract Background To elucidate the biological processes affected by changes in growth rate and nutrient availability, we have performed a comprehensive analysis of the transcriptome, proteome and metabolome responses of chemostat cultures of the yeast, Saccharomyces cerevisiae, growing at a range of growth rates and in four different nutrient-limiting conditions. Results We find significant changes in expression for many genes in each of the four nutrient-limited conditions tested. We also observe several processes that respond differently to changes in growth rate and are specific to each nutrient-limiting condition. These include carbohydrate storage, mitochondrial function, ribosome synthesis, and phosphate transport. Integrating transcriptome data with proteome measurements allows us to identify previously unrecognized examples of post-transcriptional regulation in response to both nutrient and growth-rate signals. Conclusions Our results emphasize the unique properties of carbon metabolism and the carbon substrate, the limitation of which induces significant changes in gene regulation at the transcriptional and post-transcriptional level, as well as altering how many genes respond to growth rate. By comparison, the responses to growth limitation by other nutrients involve a smaller set of genes that participate in specific pathways. See associated commentary http://www.biomedcentral.com/1741-7007/8/62

  15. Enhanced biological phosphorus removal with different carbon sources.

    Science.gov (United States)

    Shen, Nan; Zhou, Yan

    2016-06-01

    Enhanced biological phosphorus removal (EBPR) process is one of the most economical and sustainable methods for phosphorus removal from wastewater. However, the performance of EBPR can be affected by available carbon sources types in the wastewater that may induce different functional microbial communities in the process. Glycogen accumulating organisms (GAOs) and polyphosphate accumulating organisms (PAOs) are commonly found by coexisting in the EBPR process. Predominance of GAO population may lead to EBPR failure due to the competition on carbon source with PAO without contributing phosphorus removal. Carbon sources indeed play an important role in alteration of PAOs and GAOs in EBPR processes. Various types of carbon sources have been investigated for EBPR performance. Certain carbon sources tend to enrich specific groups of GAOs and/or PAOs. This review summarizes the types of carbon sources applied in EBPR systems and highlights the roles of these carbon sources in PAO and GAO competition. Both single (e.g., acetate, propionate, glucose, ethanol, and amino acid) and complex carbon sources (e.g., yeast extract, peptone, and mixed carbon sources) are discussed in this review. Meanwhile, the environmental friendly and economical carbon sources that are derived from waste materials, such as crude glycerol and wasted sludge, are also discussed and compared. PMID:27087523

  16. Identification and characterization of a freshwater microalga Scenedesmus SDEC-8 for nutrient removal and biodiesel production.

    Science.gov (United States)

    Song, Mingming; Pei, Haiyan; Hu, Wenrong; Zhang, Shuo; Ma, Guixia; Han, Lin; Ji, Yan

    2014-06-01

    The selection of the right strains is of fundamental important to the success of the algae-based oil industry. From the six newly isolated microalgae strains tested for growth, fatty acid methyl ester (FAME) profiles and biodiesel properties, Scenedesmus SDEC-8, with favorable C16:0 fatty acids (73.43%), showed the best combined results. Then, morphological and molecular identification were examined. From the three wastewaters samples, Scenedesmus SDEC-8 showed good ability to yield oil and remove nutrients, which were comparable with other reports. In b artificial wastewater (TN 40 mg L(-1), TP 8 mg L(-1)), Scenedesmus SDEC-8 achieved the highest value of lipid productivity (53.84 mg L(-1) d(-1)), MUFA content (35.35%) and total FAME content (59.57±0.02 mg g(-1) DW), besides higher removal efficiencies of TN (99.18%) and TP (98.86%) helped effluent directly discharge and smaller dilution factor of N, P (3.3 and 9) which was good for lessening water utilization. PMID:24747391

  17. Nutrient removal from separated pig manure digestate liquid using hybrid biofilters.

    Science.gov (United States)

    Zhang, Mingchuan; Lawlor, Peadar G; Hu, Zhenhu; Zhan, Xinmin

    2013-01-01

    In this study, laboratory-scale hybrid biofilters were set up to treat the separated pig manure digestate liquid at two loading rates of 0.12 and 0.07 kg N m(-3) per day. The hybrid biofilters were operated with a sequencing batch reactor mode. Over the operation of 136 days, 84% and 88% of total nitrogen was removed on average in addition with complete nitrification at the high loading rate and low loading rate, respectively. In the anoxic phase, the nitrate reduction rates were 0.31 and 0.24 mg L(-1) min(-1); and in the aerobic phase, nitrification rates were 0.29 and 0.18 mg L(-1) min(-1) at the high loading rate and low loading rate, respectively. It was found that in the hybrid biofilters, biofilm biomass had much higher nitrification and denitrification activities than suspended growth biomass. Phosphorus removals achieved were up to 88%. The results show the hybrid biofilter technology is valid for high nutrient pig manure digestate liquid treatment.

  18. Aerobic granules formation and nutrients removal characteristics in sequencing batch airlift reactor (SBAR) at low temperature

    International Nuclear Information System (INIS)

    To understand the effect of low temperature on the formation of aerobic granules and their nutrient removal characteristics, an aerobic granular sequencing batch airlift reactor (SBAR) has been operated at 10 deg. C using a mixed carbon source of glucose and sodium acetate. The results showed that aerobic granules were obtained and that the reactor performed in stable manner under the applied conditions. The granules had a compact structure and a clear out-surface. The average parameters of the granules were: diameter 3.4 mm, wet density 1.036 g mL-1, sludge volume index 37 mL g-1, and settling velocity 18.6-65.1 cm min-1. Nitrite accumulation was observed, with a nitrite accumulation rate (NO2--N/NOx--N) between 35% and 43% at the beginning of the start-up stage. During the stable stage, NOx was present at a level below the detection limit. However, when the influent COD concentration was halved (resulting in COD/N a reduction of the COD/N from 20:1 to 10:1) nitrite accumulation was observed once more with an effluent nitrite accumulation rate of 94.8%. Phosphorus release was observed in the static feeding phase and also during the initial 20-30 min of the aerobic phase. Neither the low temperature nor adjustment of the COD/P ratio from 100:1 to 25:1 had any influence on the phosphorus removal efficiency under the operating conditions. In the granular reactor with the influent load rates for COD, NH4+-N, and PO43--P of 1.2-2.4, 0.112 and 0.012-0.024 kg m-3 d-1, the respective removal efficiencies at low temperature were 90.6-95.4%, 72.8-82.1% and 95.8-97.9%.

  19. Effect of nitrogen on phosphate reduction in biological phosphorus removal from wastewater

    OpenAIRE

    Vabolienė, Giedrė; Matuzevičius, Algimantas B.; Valentukevičienė, Marina

    2007-01-01

    Conventional schemes of biological nitrogen removal can be combined with phosphorus removal schemes. One of the common technology schemes for biological nitrogen removal is the aeration zone and the anoxic zone in one tank. The nitrification and denitrification are carried out during the aeration switching on and off. The anaerobic zone is equipped behind the nitrification/denitrification tank for biological phosphorus removal. Exchange of the anaerobic and aerobic conditions is necessary for...

  20. Population dynamics of bacteria involved in enhanced biological phosphorus removal in Danish wastewater treatment plants.

    Science.gov (United States)

    Mielczarek, Artur Tomasz; Nguyen, Hien Thi Thu; Nielsen, Jeppe Lund; Nielsen, Per Halkjær

    2013-03-15

    The enhanced biological phosphorus removal (EBPR) process is increasingly popular as a sustainable method for removal of phosphorus (P) from wastewater. This study consisted of a comprehensive three-year investigation of the identity and population dynamics of polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) in 28 Danish municipal wastewater treatment plants with nutrient removal. Fluorescence in situ hybridization was applied to quantify ten probe-defined populations of PAO and GAO that in total constituted a large fraction (30% on average) of the entire microbial community targeted by the EUBmix probes. Two PAO genera, Accumulibacter and Tetrasphaera, were very abundant in all EBPR plants (average of 3.7% and 27% of all bacteria, respectively), and their abundance was relatively stable in the Danish full-scale plants without clear temporal variations. GAOs were occasionally present in some plants (Competibacter in 11 plants, Defluviicoccus in 6 plants) and were consistent in only a few plants. This shows that these were not core species in the EBPR communities. The total GAO abundance was always lower than that of Accumulibacter. In plants without EBPR design, the abundance of PAO and GAO was significantly lower. Competibacter correlated in general with high fraction of industrial wastewater. In specific plants Accumulibacter correlated with high C/P ratio of the wastewater and Tetrasphaera with high organic loading. Interestingly, the relative microbial composition of the PAO/GAO species was unique to each plant over time, which gives a characteristic plant-specific "fingerprint".

  1. ENGINEERING SOLUTION OF BIOLOGICAL TREATMENT COMPLEX WITH NUTRIENT REMOVAL BASED ON SIMULATION MODELING / ИНЖЕНЕРНОЕ РЕШЕНИЕ КОМПЛЕКСА БИОЛОГИЧЕСКОЙ ОЧИСТКИ ОТ БИОГЕННЫХ ЭЛЕМЕНТОВ НА ОСНОВЕ ИМИТАЦИОННОГО МОДЕЛИРОВАНИЯ

    OpenAIRE

    Bazhenov V. I. / Баженов Виктор Иванович; Noskova I. A. / Носкова Ирина Алексеевна

    2014-01-01

    The paper provides a mechanism for the biological purification of wastewater in the aeration tanks with nutrient removal in connection with simulation modeling, based on software GPS-X. The authors provide the example of zones design optimization for denitrification process MUCT achieved when N-NO3 = 0.3 mg/L. Presented is the typical block for biological treatment with nitrogen and phosphorus removal with flowrate 1140 m3/h due to one section of the aeration tank / Приводится механизм биолог...

  2. Optimization of biological sulfide removal in a CSTR bioreactor.

    Science.gov (United States)

    Roosta, Aliakbar; Jahanmiri, Abdolhossein; Mowla, Dariush; Niazi, Ali; Sotoodeh, Hamidreza

    2012-08-01

    In this study, biological sulfide removal from natural gas in a continuous bioreactor is investigated for estimation of the optimal operational parameters. According to the carried out reactions, sulfide can be converted to elemental sulfur, sulfate, thiosulfate, and polysulfide, of which elemental sulfur is the desired product. A mathematical model is developed and was used for investigation of the effect of various parameters on elemental sulfur selectivity. The results of the simulation show that elemental sulfur selectivity is a function of dissolved oxygen, sulfide load, pH, and concentration of bacteria. Optimal parameter values are calculated for maximum elemental sulfur selectivity by using genetic algorithm as an adaptive heuristic search. In the optimal conditions, 87.76% of sulfide loaded to the bioreactor is converted to elemental sulfur.

  3. Stabilisation of Biological Phosphorus Removal from Municipal Wastewater

    DEFF Research Database (Denmark)

    Krühne, Ulrich

    variations of the influent wastewater concentrations and are not yet always guaranteed. Even though the scientific knowledge and practical experience has reached a high level of understanding of the involved key-processes it is still necessary to apply chemical precipitation of phosphorus during the time......The biological phosphorus removal (BPR) from wastewater has developed considerably during the last decades and is applied in many present wastewater treatment plants (WWTP) all over the world. The process performance and the control of the BPR are under the influences of daily and seasonal...... have been performed on an alternating pilot plant, receiving municipal wastewater. The pilot plant is equipped with an automatic measurement system based on the flow injection analysis (FIA) principle. Continuos analysis of the ammonium (NH4-N), nitrate (as NOx-N) and phosphorus (PO4-P) was performed...

  4. A multiscale analysis of nutrient transport and biological tissue growth in vitro

    KAUST Repository

    O'Dea, R. D.

    2014-10-15

    © The authors 2014. In this paper, we consider the derivation of macroscopic equations appropriate to describe the growth of biological tissue, employing a multiple-scale homogenization method to accommodate explicitly the influence of the underlying microscale structure of the material, and its evolution, on the macroscale dynamics. Such methods have been widely used to study porous and poroelastic materials; however, a distinguishing feature of biological tissue is its ability to remodel continuously in response to local environmental cues. Here, we present the derivation of a model broadly applicable to tissue engineering applications, characterized by cell proliferation and extracellular matrix deposition in porous scaffolds used within tissue culture systems, which we use to study coupling between fluid flow, nutrient transport, and microscale tissue growth. Attention is restricted to surface accretion within a rigid porous medium saturated with a Newtonian fluid; coupling between the various dynamics is achieved by specifying the rate of microscale growth to be dependent upon the uptake of a generic diffusible nutrient. The resulting macroscale model comprises a Darcy-type equation governing fluid flow, with flow characteristics dictated by the assumed periodic microstructure and surface growth rate of the porous medium, coupled to an advection-reaction equation specifying the nutrient concentration. Illustrative numerical simulations are presented to indicate the influence of microscale growth on macroscale dynamics, and to highlight the importance of including experimentally relevant microstructural information to correctly determine flow dynamics and nutrient delivery in tissue engineering applications.

  5. Nitrification and microalgae cultivation for two-stage biological nutrient valorization from source separated urine.

    Science.gov (United States)

    Coppens, Joeri; Lindeboom, Ralph; Muys, Maarten; Coessens, Wout; Alloul, Abbas; Meerbergen, Ken; Lievens, Bart; Clauwaert, Peter; Boon, Nico; Vlaeminck, Siegfried E

    2016-07-01

    Urine contains the majority of nutrients in urban wastewaters and is an ideal nutrient recovery target. In this study, stabilization of real undiluted urine through nitrification and subsequent microalgae cultivation were explored as strategy for biological nutrient recovery. A nitrifying inoculum screening revealed a commercial aquaculture inoculum to have the highest halotolerance. This inoculum was compared with municipal activated sludge for the start-up of two nitrification membrane bioreactors. Complete nitrification of undiluted urine was achieved in both systems at a conductivity of 75mScm(-1) and loading rate above 450mgNL(-1)d(-1). The halotolerant inoculum shortened the start-up time with 54%. Nitrite oxidizers showed faster salt adaptation and Nitrobacter spp. became the dominant nitrite oxidizers. Nitrified urine as growth medium for Arthrospira platensis demonstrated superior growth compared to untreated urine and resulted in a high protein content of 62%. This two-stage strategy is therefore a promising approach for biological nutrient recovery. PMID:26998796

  6. Methanethiol Removal from Biogas by Biological Conversion in an Anaerobic Biotrickling Filter

    Institute of Scientific and Technical Information of China (English)

    王佳佳; 张卫江; 徐姣

    2015-01-01

    In this study, methanethiol(MT)-degradation bacteria were cultivated by using MT, methanol and trimethylamine as carbon sources under anaerobic conditions. It was found that the batch bacteria used MT and metha-nol as carbon sources grew faster than those used trimethylamine. The enriched bacteria used MT and methanol as the carbon sources were respectively inoculated in different biotrickling filters. The biological conversion performance of MT under anaerobic conditions was investigated in biotrickling filters. The results showed that the performance of the biotrickling filter inoculated with the bacteria enriched using MT was better than that inoculated with the bacteria en-riched using methanol. When the inlet concentration of MT was 0.005vol%(50,ppm), the empty bed residence time was 50 s, pH value was 8.0, and the flow rate of the nutrient solution was 10 L/h, the removal efficiency of MT reached 95.3%. Adding methanol stimulated the growth of the biomass and the degradation of MT, but caused that some bacteria only degrading methanol outcompeted the bacteria only degrading MT. The concentration of sodium bicarbonate in the nutrient solution needed to be controlled lower than 30 g/L, otherwise, it would be harmful to the degradation of MT.

  7. Efficacy of Chlorella pyrenoidosa and Scenedesmus abundans for Nutrient Removal in Rice Mill Effluent (Paddy Soaked Water).

    Science.gov (United States)

    Abinandan, S; Bhattacharya, Ribhu; Shanthakumar, S

    2015-01-01

    Microalgae are product of sustainable development owing to its ability to treat variety of wastewater effluents and thus produced biomass can serve as value added product for various commercial applications. This paper deals with the cultivation of microalgae species namely Chlorella pyrenoidosa and Scenedesmus abundans in rice mill effluent (i.e., paddy soaked water) for nutrient removal. In order to investigate the nutrient removal capability, microalgae are subjected to cultivation in both raw and autoclaved samples. The maximum phosphate removal by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 98.3% and 97.6%, respectively, whereas, the removal of ammoniacal nitrogen by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 92% and 90.3%, respectively. The growth (measured in terms of chlorophyll content) of Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 3.88 mg/l and 5.55 mg/l, respectively. The results indicate the suitability of microalgae cultivation in rice mill effluent treatment for nutrient removal.

  8. Nutrient removal capacity of wood residues for the Agro-environmental safety of ground and surface waters

    Directory of Open Access Journals (Sweden)

    Paulo A. Dumont

    2014-07-01

    Full Text Available The aim of this study was to determine the effectiveness of wood residues in the removal of nutrients (ammonium-N; NH4-N from nutrient-rich (NH4-N waters. The water holding capacity of the wood materials was also determined. Carried out at Rothamsted Research, North Wyke, UK, this controlled laboratory experiment tested two wood residues; in length, one being 1-2cm and the other from 150 µm (microns to 9.5mm. Although a wide range of studies have shown the effectiveness and performance of various absorbent materials as animal beddings, such as straw (cereal straw, woodchip (sawdust, bark or wood shavings, bracken and rushes, only few have focused on the NH4-N sorption/desorption capacity. The depuration capacity of wood residues from nutrient-rich effluents such as those from cattle bedded on woodchip or straw will be controlled by processes such as sorption (adsorption-absorption and desorption of nutrients. Studies have reported the nitrogen removal capacity of woodchip materials and biochar from woodchip as well as removal of NH4+-N from domestic and municipal wastewater, farm dirty water, landfill and industry effluents. These studies have observed that the mechanism of removal of nitrogen is by either increasing NO3--N removal form leachate by enhancing N2O losses via denitrification (biochar as carbon source for denitrifiers or by decreasing NH4+-N in leachate through adsorption to negatively charged sites. Results showed that although the cation exchange capacity (CEC and surface area (SA are both fundamental properties of adsorbent materials, no correlation was found with CEC and adsorption or desorption. Nor did changes in pH appear to be sufficiently important to cause changes in CEC. For this reason, osmotic pressure appeared to be a more predominant parameter controlling processes of adsorption and desorption of NH4+-N in both wood residues. Thus, wood residues high in NH4+-N should be avoided, as they could have an opposite effect

  9. Grazer removal and nutrient enrichment as recovery enhancers for overexploited rocky subtidal habitats.

    Science.gov (United States)

    Guarnieri, Giuseppe; Bevilacqua, Stanislao; Vignes, Fabio; Fraschetti, Simonetta

    2014-07-01

    Increasing anthropogenic pressures are causing long-lasting regime shifts from high-diversity ecosystems to low-diversity degraded ones. Understanding the effects of multiple threats on ecosystems, and identifying processes allowing for the recovery of biodiversity, are the current major challenges in ecology. In several temperate marine areas, large parts of rocky subtidal habitats characterised by high diversity have been completely degraded to barren grounds by overfishing, including illegal date mussel fishing. Bare areas are characterized by the dominance of sea urchins whose grazing perpetuates the impact of overfishing. We investigated experimentally the separate and combined effects of nutrient enrichment and sea urchin exclusion on the recovery of barren grounds. Our results indicate that the two factors have a synergistic effect leading to the re-establishment of erect macroalgal canopies, enhancing the structural complexity of subtidal assemblages. In particular, in the overfished system considered here, the recovery of disturbed assemblages could occur only if sea urchins are removed. However, the recolonization of barren grounds by erect macroalgae is further enhanced under enriched conditions. This study demonstrates that the recovery of dramatically depleted marine habitats is possible, and provides useful indications for specific management actions, which at present are totally lacking, to achieve the restoration of barren grounds caused by human activity.

  10. Microalgae treatment removes nutrients and reduces ecotoxicity of diluted piggery digestate.

    Science.gov (United States)

    Franchino, Marta; Tigini, Valeria; Varese, Giovanna Cristina; Mussat Sartor, Rocco; Bona, Francesca

    2016-11-01

    Liquid digestate is considered as an important by-product of anaerobic digestion of agriculture wastes. Currently, it is very often directly spread on local agricultural land. Yet recently concerns on its environmental risk of this processing has begun to rise. On the other hand, investigations on the effectiveness of microalgae for wastewater treatment have started to consider also this complex matrix. In this study, we cultured the green alga Chlorella vulgaris in diluted digestate coming from the anaerobic digestion of pig slurry and corn, with the aim to significantly reduce its toxicity and its very high nutrient concentration. For this purpose, a battery of toxicity tests composed of four acute and two chronic bioassays was applied after the alga cultivation. Results were compared with those obtained in the initial characterization of the digestate. Results show that highly diluted piggery digestate can be a suitable medium for culturing microalgae, as we obtained a high removal efficiency (>90%) for ammonia, total nitrogen and phosphate, though after a few days phosphorus limitation occurred. Toxicity was significantly reduced for all the organisms tested. Possible solutions for optimizing this approach avoiding high dilution rates are discussed. PMID:27328398

  11. Comparing two surface flow wetlands for removal of nutrients in agricultural drainage water

    DEFF Research Database (Denmark)

    Hoffmann, Carl Christian; Kjærgaard, Charlotte; Levesen, Bo;

    In Denmark there is a growing interest for using constructed wetlands as a mean for removal of nutrients from agricultural run-off, such as drainage ditches and tile drainage systems. We have studied two surface flow constructed wetlands from district Vejle, Jutland, Denmark. The Vicarage Wetland...... was constructed in 2006 and put into operation in December 2006. It is the pond type with an area of 877 m2 and a volume of 200 m3. The inlet, which stems from a drainage system, consists of a small stream with wet riparian areas with an area of 1222 m2 and 103 m2 open water. Mean hydraulic load is 3.7 l s-1...... m2, respectively. In between the two ponds is a small wetland with an area of 745 m2. Inlet water comes from a drainage system and mean hydraulic load is 5.7 l s-1, and the volume of the ponds is 90 and 400 m3, respectively, thus giving a residence time of approximately 24 hours. The two ponds only...

  12. Aerobic granules formation and nutrients removal characteristics in sequencing batch airlift reactor (SBAR) at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Bao Ruiling [State Key Laboratory of Urban Water Resource and Environment, Harbin University of Technology, Harbin 150090 (China); Yu Shuili, E-mail: ysl@vip.163.com [State Key Laboratory of Urban Water Resource and Environment, Harbin University of Technology, Harbin 150090 (China) and State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092 (China); Shi Wenxin; Zhang Xuedong; Wang Yulan [State Key Laboratory of Urban Water Resource and Environment, Harbin University of Technology, Harbin 150090 (China)

    2009-09-15

    To understand the effect of low temperature on the formation of aerobic granules and their nutrient removal characteristics, an aerobic granular sequencing batch airlift reactor (SBAR) has been operated at 10 deg. C using a mixed carbon source of glucose and sodium acetate. The results showed that aerobic granules were obtained and that the reactor performed in stable manner under the applied conditions. The granules had a compact structure and a clear out-surface. The average parameters of the granules were: diameter 3.4 mm, wet density 1.036 g mL{sup -1}, sludge volume index 37 mL g{sup -1}, and settling velocity 18.6-65.1 cm min{sup -1}. Nitrite accumulation was observed, with a nitrite accumulation rate (NO{sub 2}{sup -}-N/NO{sub x}{sup -}-N) between 35% and 43% at the beginning of the start-up stage. During the stable stage, NO{sub x} was present at a level below the detection limit. However, when the influent COD concentration was halved (resulting in COD/N a reduction of the COD/N from 20:1 to 10:1) nitrite accumulation was observed once more with an effluent nitrite accumulation rate of 94.8%. Phosphorus release was observed in the static feeding phase and also during the initial 20-30 min of the aerobic phase. Neither the low temperature nor adjustment of the COD/P ratio from 100:1 to 25:1 had any influence on the phosphorus removal efficiency under the operating conditions. In the granular reactor with the influent load rates for COD, NH{sub 4}{sup +}-N, and PO{sub 4}{sup 3-}-P of 1.2-2.4, 0.112 and 0.012-0.024 kg m{sup -3} d{sup -1}, the respective removal efficiencies at low temperature were 90.6-95.4%, 72.8-82.1% and 95.8-97.9%.

  13. Comparing results of cultured and uncultured biological methods used in biological phosphorus removal

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Increasing attention has been paid to phosphate-accumulating organisms (PAOs) for their important role in biological phosphorus removal. In this study, microbial communities of PAOs cultivated under different carbon sources (sewage, glucose, and sodium acetate) were investigated and compared through culture-dependent and culture-independent methods, respectively. The results obtained using denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction-amplified 16S rDNA fragments revealed that the diversity of bacteria in a sewage-fed reactor (1#) was much higher than in a glucose-fed one (2#) and a sodium acetate-fed one (3#); there were common PAOs in three reactors fed by different carbon sources. Five strains were separated from three systems by using a phosphate-rich medium; they were from common bacteria isolated and three isolates could not be found in DGGE profile at all. Two isolates had good phosphorus removal ability. When the microbial diversity was studied, the molecular biological method was better than the culture-dependent one. When phosphorus removal characteristics were investigated, culture-dependent approach was more effective. Thus a combination of two methods is necessary to have a comprehensive view of PAOs.

  14. Past, present and future of technologies for nutrient removal in WWTP; Pasado, presente y futuro de tecnologias para la eliminacion de nutrientes en EDAR

    Energy Technology Data Exchange (ETDEWEB)

    Larrea Urcola, L.

    2012-07-01

    In the past decades, nitrogen and phosphorous (nutrient) removal from urban wastewater has been carried out throughout the world mainly using different reactor configurations of activated sludge processes like A{sup 2} O, UCT, etc. Since 2000, three innovative technologies that mitigate activated sludge processes limitations have been introduced in new and existing plants as they operate with high biomass concentration and without filamentous bulking. One technology is the membrane bioreactor where similar configurations to activated slugged processes are applied, but the secondary settler is replaced by a membrane tank. The two other technologies are based on biofilm processes: One is the submerged granular bio filter where a fixed bed of small supports of 3-8 mm causes biodegradation and filtration phenomena, thus not requiring a secondary settler. The second one is the IFAS hybrid process where moving plastic supports promotes nitrification in the biofilm, while denitrification and phosphorous removal take place in suspension. In order to meet stricter effluent nitrogen requirements, currently nitrogen removal from the water in the sludge line that returns to the head of the plant, is proposed. Innovative technologies are based on partial nitrification and anammox, using biomass in suspension, in biofilm and in granules. With a horizon application in the medium term, emergent technologies are being developed, like granular processes, combination of membrane and biofilm systems and the recovery of nutrients in the context of the WWTP as a facility of resources. (Author)

  15. Nutrient removal capacity of wood residues for the Agro-environmental safety of ground and surface waters

    OpenAIRE

    Paulo A. Dumont; Chadwick, David R.; Steve Robinson

    2014-01-01

    The aim of this study was to determine the effectiveness of wood residues in the removal of nutrients (ammonium-N; NH4-N) from nutrient-rich (NH4-N) waters. The water holding capacity of the wood materials was also determined. Carried out at Rothamsted Research, North Wyke, UK, this controlled laboratory experiment tested two wood residues; in length, one being 1-2cm and the other from 150 µm (microns) to 9.5mm. Although a wide range of studies have shown the effectiveness and performance of ...

  16. Factors affecting population of filamentous bacteria in wastewater treatment plants with nutrients removal.

    Science.gov (United States)

    Miłobędzka, Aleksandra; Witeska, Anna; Muszyński, Adam

    2016-01-01

    Filamentous population in activated sludge and key operational parameters of full-scale municipal wastewater treatment plants (WWTPs) with bulking problems representative for Poland were investigated with quantitative fluorescence in situ hybridization. Statistical analyses revealed few relationships between operational parameters and biovolume of filamentous bacteria. Sludge age was not only positively correlated with abundance of Chloroflexi (parametric correlation and principal component analysis (PCA)), but also differentiated Microthrix population (analysis of variance (ANOVA)). Phylum Chloroflexi and pH presented a negative relation during the study (PCA). ANOVA showed that pH of influent and sludge volume index (SVI) differentiated abundance of types 0803 and 1851 of Chloroflexi and candidate division TM7. SVI increased along with higher abundance of Microthrix (positive parametric and non-parametric correlations and positive relation in PCA). Biovolumes of morphotypes 0803 and 1851 of Chloroflexi were differentiated by organic matter in influent, also by nutrients in the case of Chloroflexi type 1851. Chemical and biological oxygen demands (COD and BOD5, respectively) were negatively correlated with Microthrix. COD also differentiated the abundance of Haliscomenobacter hydrossis. Results of the study can be used to prevent WWTPs from excessive proliferation of filamentous bacteria and operational problems caused by them--bulking and foaming of activated sludge.

  17. From Earth to Space: Application of Biological Treatment for the Removal of Ammonia from Water

    Science.gov (United States)

    Pickering, Karen; Adam, Niklas; White, Dawn; Ghosh, Amlan; Seidel, Chad

    2014-01-01

    Managing ammonia is often a challenge in both drinking water and wastewater treatment facilities. Ammonia is unregulated in drinking water, but its presence may result in numerous water quality issues in the distribution system such as loss of residual disinfectant, nitrification, and corrosion. Ammonia concentrations need to be managed in wastewater effluent to sustain the health of receiving water bodies. Biological treatment involves the microbiological oxidation of ammonia to nitrate through a two-step process. While nitrification is common in the environment, and nitrifying bacteria can grow rapidly on filtration media, appropriate conditions, such as the presence of dissolved oxygen and required nutrients, need to be established. This presentation will highlight results from two ongoing research programs - one at NASA's Johnson Space Center, and the other at a drinking water facility in California. Both programs are designed to demonstrate nitrification through biological treatment. The objective of NASA's research is to be able to recycle wastewater to potable water for spaceflight missions. To this end, a biological water processor (BWP) has been integrated with a forward osmosis secondary treatment system (FOST). Bacteria mineralize organic carbon to carbon dioxide as well as ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrification and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system testing planned for this year is expected to produce water that requires only a polishing step to meet potable water requirements for spaceflight. The pilot study in California is being conducted on Golden State Water Company's Yukon wells that have hydrogen sulfide odor

  18. Removal of chemical oxygen demand and dissolved nutrients by a sunken lawn infiltration system during intermittent storm events.

    Science.gov (United States)

    Hou, Lizhu; Yang, Huan; Li, Ming

    2014-01-01

    Urban surface water runoff typically contains high but varying amounts of organic matter and nutrients that require removal before reuse. Infiltration systems such as sunken lawns can improve water quality. However, there is currently insufficient information describing the treatment efficiency of lawn-based infiltration systems. In this study, novel sunken lawn infiltration systems (SLISs) were designed and their pollutant removal effectiveness was assessed. The results revealed that SLISs with Poa pratensis and Lolium perenne effectively removed most chemical oxygen demand (CODCr) and dissolved nutrients. Average CODCr, total nitrogen (TN), ammonium-nitrogen (NH4(+)-N) and total phosphorus (TP) concentrations were reduced by 78.93, 66.64, 71.86 and 75.83%, respectively, and the corresponding effluent concentrations met the standard for urban miscellaneous water consumption in China. The NH4(+)-N in the synthetic runoff was shown to be removed by adsorption during the stormwater dosing and nitrification during subsequent dry days, as well as through uptake by plants. Phosphorus was mainly removed by adsorption and chemical precipitation. The NH4(+)-N and phosphorus Langmuir isotherm model fitted the clay loam soil adsorption process better than the Freundlich model. Overall, these results indicate that an SLIS provides an alternative means of removing runoff pollutants owing to its efficiency, easy operation and maintenance. PMID:24473312

  19. Heterogeneity of intracellular polymer storage states in enhanced biological phosphorus removal (EBPR)--observation and modeling.

    Science.gov (United States)

    Bucci, Vanni; Majed, Nehreen; Hellweger, Ferdi L; Gu, April Z

    2012-03-20

    A number of agent-based models (ABMs) for biological wastewater treatment processes have been developed, but their skill in predicting heterogeneity of intracellular storage states has not been tested against observations due to the lack of analytical methods for measuring single-cell intracellular properties. Further, several mechanisms can produce and maintain heterogeneity (e.g., different histories, uneven division) and their relative importance has not been explored. This article presents an ABM for the enhanced biological phosphorus removal (EBPR) treatment process that resolves heterogeneity in three intracellular polymer storage compounds (i.e., polyphosphate, polyhydroxybutyrate, and glycogen) in three functional microbial populations (i.e., polyphosphate-accumulating, glycogen-accumulating, and ordinary heterotrophic organisms). Model predicted distributions were compared to those based on single-cell estimates obtained using a Raman microscopy method for a laboratory-scale sequencing batch reactor (SBR) system. The model can reproduce many features of the observed heterogeneity. Two methods for introducing heterogeneity were evaluated. First, biological variability in individual cell behavior was simulated by randomizing model parameters (e.g., maximum acetate uptake rate) at division. This method produced the best fit to the data. An optimization algorithm was used to determine the best variability (i.e., coefficient of variance) for each parameter, which suggests large variability in acetate uptake. Second, biological variability in individual cell states was simulated by randomizing state variables (e.g., internal nutrient) at division, which was not able to maintain heterogeneity because the memory in the internal states is too short. These results demonstrate the ability of ABM to predict heterogeneity and provide insights into the factors that contribute to it. Comparison of the ABM with an equivalent population-level model illustrates the effect

  20. Present and perspective of enhanced biological phosphorus removal process; Seibutsugakuteki rin jokyoho no genjo to kadai

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, K. [National Inst. of Bioscience and Human-Technology, Tsukuba (Japan)

    1997-02-05

    Biological phosphorus removal process utilizing anaerobic and aerobic conditions, mechanism of phosphorus removal, and microbes relating to phosphorus removal are outlined, and future problems are discussed. By mixing waste water and sludge under anaerobic condition followed by treatment under aerobic condition, phosphorus content in sludge increases to enable biological phosphorus removal. More microbes with high polyphosphorus accumulating performance are acquired by the anaerobic/aerobic process than other microbes with the result of their preferential increase, and the process has high phosphorus removal characteristic than the general treatment process. Microbes relating to phosphorus removal, immobilization of polyphosphate accumulating microbes, and phosphorus acquiring and releasing characteristics of immobilized mycelium are discussed. Application of gel entrapped immobilized mycelium to phosphorus removal and problems in biological phosphorus removing methods are described. 18 refs., 12 figs.

  1. Biological and chemical removal of Cr(VI) from waste water: cost and benefit analysis.

    Science.gov (United States)

    Demir, Aynur; Arisoy, Münevver

    2007-08-17

    The objective of the present study is cost and benefit analysis of biological and chemical removal of hexavalent chromium [Cr(VI)] ions. Cost and benefit analysis were done with refer to two separate studies on removal of Cr(VI), one of heavy metals with a crucial role concerning increase in environmental pollution and disturbance of ecological balance, through biological adsorption and chemical ion-exchange. Methods of biological and chemical removal were compared with regard to their cost and percentage in chrome removal. According to the result of the comparison, cost per unit in chemical removal was calculated 0.24 euros and the ratio of chrome removal was 99.68%, whereas those of biological removal were 0.14 and 59.3% euros. Therefore, it was seen that cost per unit in chemical removal and chrome removal ratio were higher than those of biological removal method. In the current study where chrome removal is seen as immeasurable benefit in terms of human health and the environment, percentages of chrome removal were taken as measurable benefit and cost per unit of the chemicals as measurable cost.

  2. Influence of wastewater composition on nutrient removal behaviors in the new anaerobic–anoxic/nitrifying/induced crystallization process

    OpenAIRE

    Shi, Jing; Xiwu LU; Yu, Ran; Gu, Qian; Zhou, Yi

    2013-01-01

    In this study, the new anaerobic–anoxic/nitrifying/induced crystallization (A2N–IC) system was compared with anaerobic-anoxic/nitrifying (A2N) process to investigate nutrient removal performance under different influent COD and ammonia concentrations. Ammonia and COD removal rates were very stable in both processes, which were maintained at 84.9% and 86.6% when the influent ammonia varied from 30 mg L−1 to 45 mg L−1 and COD ranged from 250 mg L−1 to 300 mg L−1. The effluent phosphorus always ...

  3. A GAO hiding among the PAO: The role of the Propionivibrio spp. in biological phosphorus removal

    DEFF Research Database (Denmark)

    McIlroy, Simon Jon; Albertsen, Mads; Stokholm-Bjerregaard, Mikkel;

    Enhanced biological phosphorus removal (EBPR) is widely used to remove phosphorus from wastewater. The process relies on polyphosphate accumulating organisms (PAOs) that are able to take up phosphorus in excess of what is needed for growth, whereby phosphorus can be removed from the wastewater...

  4. Microbiological study of bacteriophage induction in the presence of chemical stress factors in enhanced biological phosphorus removal (EBPR).

    Science.gov (United States)

    Motlagh, Amir Mohaghegh; Bhattacharjee, Ananda S; Goel, Ramesh

    2015-09-15

    Polyphosphate accumulating organisms (PAOs) are responsible for carrying the enhanced biological phosphorus removal (EBPR). Although the EBPR process is well studied, the failure of EBPR performance at both laboratory and full-scale plants has revealed a lack of knowledge about the ecological and microbiological aspects of EBPR processes. Bacteriophages are viruses that infect bacteria as their sole host. Bacteriophage infection of polyphosphate accumulating organisms (PAOs) has not been considered as a main contributor to biological phosphorus removal upsets. This study examined the effects of different stress factors on the dynamics of bacteriophages and the corresponding effects on the phosphorus removal performance in a lab-scale EBPR system. The results showed that copper (heavy metal), cyanide (toxic chemical), and ciprofloxacin (antibiotic), as three different anthropogenic stress factors, can induce phages integrated onto bacterial genomes (i.e. prophages) in an enriched EBPR sequencing batch reactor, resulting in a decrease in the polyphosphate kinase gene ppk1 clades copy number, phosphorus accumulation capacity, and phosphorus removal performance. This study opens opportunities for further research on the effects of bacteriophages in nutrient cycles both in controlled systems such as wastewater treatment plants and natural ecosystems. PMID:26024959

  5. An efficient process for wastewater treatment to mitigate free nitrous acid generation and its inhibition on biological phosphorus removal

    Science.gov (United States)

    Zhao, Jianwei; Wang, Dongbo; Li, Xiaoming; Yang, Qi; Chen, Hongbo; Zhong, Yu; An, Hongxue; Zeng, Guangming

    2015-02-01

    Free nitrous acid (FNA), which is the protonated form of nitrite and inevitably produced during biological nitrogen removal, has been demonstrated to strongly inhibit the activity of polyphosphate accumulating organisms (PAOs). Herein we reported an efficient process for wastewater treatment, i.e., the oxic/anoxic/oxic/extended-idle process to mitigate the generation of FNA and its inhibition on PAOs. The results showed that this new process enriched more PAOs which thereby achieved higher phosphorus removal efficiency than the conventional four-step (i.e., anaerobic/oxic/anoxic/oxic) biological nutrient removal process (41 +/- 7% versus 30 +/- 5% in abundance of PAOs and 97 +/- 0.73% versus 82 +/- 1.2% in efficiency of phosphorus removal). It was found that this new process increased pH value but decreased nitrite accumulation, resulting in the decreased FNA generation. Further experiments showed that the new process could alleviate the inhibition of FNA on the metabolisms of PAOs even under the same FNA concentration.

  6. Identification of a Novel Group of Bacteria in Sludge from a Deteriorated Biological Phosphorus Removal Reactor

    OpenAIRE

    Nielsen, Alex T.; Liu, Wen-Tso; Filipe, Carlos; Grady, Leslie; Molin, Søren; Stahl, David A

    1999-01-01

    The microbial diversity of a deteriorated biological phosphorus removal reactor was investigated by methods not requiring direct cultivation. The reactor was fed with media containing acetate and high levels of phosphate (P/C weight ratio, 8:100) but failed to completely remove phosphate in the effluent and showed very limited biological phosphorus removal activity. Denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA was used to investigate the bacterial diversit...

  7. Effect of subalpine canopy removal on snowpack, soil solution, and nutrient export, Fraser Experimental Forest, CO

    Science.gov (United States)

    Stottlemyer, R.; Troendle, C.A.

    1999-01-01

    proportionally greater than water flux. Increased subsurface flow accounted for most of the increase in non-limiting nutrient loss. For limiting nutrients, loss of plant uptake and increased shallow subsurface flow accounted for the greater loss. Seasonal ion concentration patterns in streamwater and subsurface flow were similar.Research on the effects of vegetation manipulation on snowpack, soil water, and streamwater chemistry and flux has been underway at the Fraser Experimental Forest (FEF), CO, since 1982. Greater than 95% of FEF snowmelt passes through watersheds as subsurface flow where soil processes significantly alter meltwater chemistry. To better understand the mechanisms accounting for annual variation in watershed streamwater ion concentration and flux with snowmelt, we studied subsurface water flow, its ion concentration, and flux in conterminous forested and clear cut plots. Repetitive patterns in subsurface flow and chemistry were apparent. Control plot subsurface flow chemistry had the highest ion concentrations in late winter and fall. When shallow subsurface flow occurred, its Ca2+, SO42-, and HCO3- concentrations were lower and K+ higher than deep flow. The percentage of Ca2+, NO3-, SO42-, and HCO3- flux in shallow depths was less and K+ slightly greater than the percentage of total flow. Canopy removal increased precipitation reaching the forest floor by about 40%, increased peak snowpack water equivalent (SWE) > 35%, increased the average snowpack Ca2+, NO3-, and NH4+ content, reduced the snowpack K+ content, and increased the runoff four-fold. Clear cutting doubled the percentage of subsurface flow at shallow depths, and increased K+ concentration in shallow subsurface flow and NO3- concentrations in both shallow and deep flow. The percentage change in total Ca2+, SO42-, and HCO3- flux in shallow depths was less than the change in water flux, while that of K+ and NO3- flux was greater. Relative to the control, in the clear cut the percentage of total Ca

  8. Removal of nutrients and organic pollution load from pulp and paper mill effluent by microalgae in outdoor open pond.

    Science.gov (United States)

    Usha, M T; Sarat Chandra, T; Sarada, R; Chauhan, V S

    2016-08-01

    A mixed culture of microalgae, containing two Scenedesmus species, was analysed to determine its potential in coupling of pulp and paper mill effluent treatment and microalgal cultivation. Laboratory studies suggested that 60% concentration of wastewater was optimum for microalgal cultivation. A maximum of 82% and 75% removal of BOD and COD respectively was achieved with microalgal cultivation in outdoor open pond. By the end of the cultivation period, 65% removal of NO3-N and 71.29% removal of PO4-P was observed. The fatty acid composition of mixed microalgal culture cultivated with effluent showed the palmitic acid, oleic acid, linoleic acid and α-linolenic acid as major fatty acids. The results obtained suggest that pulp and paper mill effluent could be used effectively for cultivation of microalgae to minimise the freshwater and nutrient requirements. PMID:27161156

  9. Effect of tetracycline on the growth and nutrient removal capacity of Chlamydomonas reinhardtii in simulated effluent from wastewater treatment plants.

    Science.gov (United States)

    Li, Jie; Zheng, Xiaoqian; Liu, Kaichuan; Sun, Shujuan; Li, Xiaochen

    2016-10-01

    The aim of this work was to study the effect of tetracycline, which is on the growth, physiological characteristics, and contaminants removal by Chlamydomonas reinhardtii. The results showed that the biomass and photosynthetic pigment concentration of C. reinhardtii exposed to tetracycline were lower than those of the control, while the superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, and the malondialdehyde (MDA) content, were higher than those of the control. Additionally, when the tetracycline concentration reached 0.25mg/L, the removal of total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) decreased from 80.8 to 55.0%, 100 to 92.5%, and 36.5 to 11.5%, respectively. Thus, tetracycline concentrations of 0-0.25mg/L are expected to have a significant effect on the growth and nutrient removal of C. reinhardtii in recycled water from wastewater treatment plants. PMID:27472492

  10. Improving the Effectiveness of a Nutrient Removal System Composed of Microalgae and Daphnia by an Artificial Illumination

    Directory of Open Access Journals (Sweden)

    In-Ho Chang

    2014-03-01

    Full Text Available For determining the effect of illumination on nutrient removal in an artificial food web (AFW system, we launched a pilot continuous-flow system. The system consisted of a storage basin, a phytoplankton growth chamber, and a zooplankton growth chamber. A 25,000 Lux AFW-light emitting diode (LED on system and an AFW-LED off system were separately operated for 10 days. In the AFW-LED on system, the maximum chlorophyll-a concentration of the phytoplankton chamber was four times higher than that of the AFW-LED off system. With artificial nighttime illumination, the microalgae became both smaller and more nutritious; the microalgae became high quality food for the zooplankton, Daphnia magna. Consequently, this zooplankton became more efficient at extracting nutrients and grew more densely than in the AFW-LED off system condition. In the LED-on condition, the amounts of total nitrogen (TN and total phosphorus (TP flowing into the system for 10 days were 84.7 g and 20.4 g, and the amounts flowing out were 19.5 g (23% and 4.0 g (20%, respectively. In contrast, in the LED-off condition, 83.8 g and 20.6 g of TN and TP flowed into the system while 38.8 g (46% and 6.8 g (33% flowed out, respectively. Artificial illumination significantly improves the removal rate of nutrients in an AFW system.

  11. Long-term study on the impact of temperature on enhanced biological phosphorus and nitrogen removal in membrane bioreactor.

    Science.gov (United States)

    Sayi-Ucar, N; Sarioglu, M; Insel, G; Cokgor, E U; Orhon, D; van Loosdrecht, M C M

    2015-11-01

    The study involved experimental observation and performance evaluation of a membrane bioreactor system treating municipal wastewater for nutrient removal for a period 500 days, emphasizing the impact of high temperature on enhanced biological phosphorus removal (EBPR). The MBR system was operated at relatively high temperatures (24-41 °C). During the operational period, the total phosphorus (TP) removal gradually increased from 50% up to 95% while the temperature descended from 41 to 24 °C. At high temperatures, anaerobic volatile fatty acid (VFA) uptake occurred with low phosphorus release implying the competition of glycogen accumulating organisms (GAOs) with polyphosphate accumulating organisms (PAOs). Low dissolved oxygen conditions associated with high wastewater temperatures did not appreciable affected nitrification but enhanced nitrogen removal. Dissolved oxygen levels around 1.0 mgO2/L in membrane tank provided additional denitrification capacity of 6-7 mgN/L by activating simultaneous nitrification and denitrification. As a result, nearly complete removal of nitrogen could be achieved in the MBR system, generating a permeate with no appreciable nitrogen content. The gross membrane flux was 43 LMH corresponding to the specific permeability (K) of 413 LMH/bar at 39 °C in the MBR tank. The specific permeability increased by the factor of 43% at 39 °C compared to that of 25 °C during long-term operation. PMID:26204227

  12. Simultaneous removal of color, organic compounds and nutrients in azo dye-containing wastewater using up-flow constructed wetland

    International Nuclear Information System (INIS)

    Combination of aerobic and anaerobic processes in constructed wetlands can enhance the treatment performance in textile wastewater. This study assessed the treatment of azo dye Acid Orange 7 (AO7) and nutrients using five laboratory-scale up-flow constructed wetlands (UFCW) with and without supplementary aeration, and with different emergent plants. Supplementary aeration controlled the size of aerobic and anaerobic zones in the UFCW reactors as evidenced by the oxidation-reduction potential (ORP) and dissolved oxygen (DO) profile of the UFCW. The AO7 removal efficiency was above 95% in all UFCW reactors and most of the color was extensively removed in the anaerobic region of the UFCW beds. The intermediates produced through the breakage of azo bond were significantly reduced in the UFCW reactors with supplementary aeration. The results indicated the applicability of the UFCW reactors to the treatment of azo dye-containing wastewater. The removals of T-N and T-P were in the range of 60-67% and 26-37%, respectively, among the UFCW reactors. The COD and NH4-N removals in the aerated reactors were about 86 and 96%, respectively. On the other hand, the COD and NH4-N removals were in the range of 78-82% and 41-48%, respectively, in the non-aerated reactors. The supplementary aeration enhanced the removal efficiencies in organic matter, NH4-N and aromatic amines in the UFCW reactors.

  13. Biological removal of iron and manganese in rapid sand filters - Process understanding of iron and manganese removal

    DEFF Research Database (Denmark)

    Lin, Katie

    to precipitation and corrosion. Manganese and iron can either be removed physico-chemically or biologically or combined. The physico-chemical oxidation and precipitation of manganese can theoretically be achieved by aeration, but this process is slow unless pH is raised far above neutral, making the removal...... of manganese by simple aeration and precipitation under normal drinking water treatment conditions insignificant. Manganese may also be oxidized autocatalytically. Iron is usually easier to remove. First, iron is rapidly chemically oxidized by oxygen at neutral pH followed by precipitation and filtration......-filter, where iron is removed. Step 2: Filtration in an after-filter where e.g. ammonium and manganese is removed. The treatment relies on microbial processes and may present an alternative, greener and more sustainable approach for drinking water production spending less chemicals and energy than chemical (e...

  14. EBP2R - an innovative enhanced biological nutrient recovery activated sludge system to produce growth medium for green microalgae cultivation.

    Science.gov (United States)

    Valverde-Pérez, Borja; Ramin, Elham; Smets, Barth F; Plósz, Benedek Gy

    2015-01-01

    Current research considers wastewater as a source of energy, nutrients and water and not just a source of pollution. So far, mainly energy intensive physical and chemical unit processes have been developed to recover some of these resources, and less energy and resource demanding alternatives are needed. Here, we present a modified enhanced biological phosphorus removal and recovery system (referred to as EBP2R) that can produce optimal culture media for downstream micro-algal growth in terms of N and P content. Phosphorus is recovered as a P-stream by diversion of some of the effluent from the upstream anaerobic reactor. By operating the process at comparably low solids retention times (SRT), the nitrogen content of wastewater is retained as free and saline ammonia, the preferred form of nitrogen for most micro-algae. Scenario simulations were carried out to assess the capacity of the EBP2R system to produce nutrient rich organic-carbon depleted algal cultivation media of target composition. Via SRT control, the quality of the constructed cultivation media can be optimized to support a wide range of green micro-algal growth requirements. Up to 75% of the influent phosphorus can be recovered, by diverting 30% of the influent flow as a P-stream at an SRT of 5 days. Through global sensitivity analysis we find that the effluent N-to-P ratio and the P recovered are mainly dependent on the influent quality rather than on biokinetics or stoichiometry. Further research is needed to demonstrate that the system performance predicted through the model-based design can be achieved in reality. PMID:25480432

  15. Evaluation of biological removal efficiency in a UCT process treating municipal wastewater during start-up stage.

    Science.gov (United States)

    Wang, Zhu; Liu, Bo; Liu, Yong-De; Wan, Fujun

    2013-04-01

    This study reports the performance of University of Cape Town (UCT) municipal wastewater treatment plant, during the startup stage with the focus on the relationship between hydraulic retention time (HRT) and biological nutrient removal (BNR) efficiency. The entire experimental period was 144 days, divided into four periods. Results showed that the removal efficiency of TN, NH4+-N, and Kjeldahl nitrogen (KN) was closely related to the HRT. Furthermore, the biodegradation kinetics analysis was used to calculate the specific degradation rates of pollutants. The GPS-X modeling was also used to examine the effect of the UCT pilot plant on BNR. The UCT pilot plant used in this study achieved high BNR efficiency even during the startup stage. With HRT of 24 hr (Period 1, day 1-40, data set 1-10), the highest levels of TN, NH(4+)-N and KN removal efficiency were approximately 72, 76 and 78%, respectively. The COD showed consistent high removal efficiency, with the highest level of approximately 96% at HRT of 15 hr (Period 3, day 81-120, data set 21-30). The TP removal efficiency rose at first and subsequently decreased abruptly. The maximum removal efficiency was 85% with HRT of 19 hr (Period 2, day 41-80, data set 11-20). With the optimal HRT 19 hr, the average removal efficiency values of COD, TP, TN, NH(4+)-N and KN were 89, 80, 65, 67 and 68%, respectively. The GPS-X modeling results indicated that the UCT process was effective in COD, TP and TN removal. PMID:24620618

  16. Efficiency and kinetic modeling of removal of nutrients and organic matter from a full-scale constructed wetland in Qasre-Shirin, Iran

    OpenAIRE

    Abdolmajid Gholizadeh; Mitra Gholami; Reza Davoudi; Ayoob Rastegar; Mohammad Miri

    2015-01-01

    Background: This study assessed the removal of organic material and nutrients from full-scale subsurface flow (SSF) constructed wetlands (CWs) followed by anaerobic stabilization ponds under environmental conditions. Methods: The effluents were distributed evenly in 12 reed beds. Samples were taken twice monthly for a total of 6 months from several points in the wetland. Biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and nutrient removal from t...

  17. Enhanced biological phosphorus removal - results of experiences in three large waste water treatment plants

    International Nuclear Information System (INIS)

    Within a scientific project especially the operation of four real-size sewage treatment plants with different processes of enhanced biological phosphorus removal is investigated under the aspect of efficiency, stability, practicability and costs of the enhanced biological phosphorus removal. Three plants and first results are explained and compared as well with one another as with data, which are generally regarded as favourable conditions for the enhanced biological phosphorus removal. Between the plants there are significant differences in the degree of P-elimination mainly due to different characteristics of the wastewater. An important influence on P-effluent concentrations may be exacted by P-resolution in the final clarifier. (orig.)

  18. Performance of subsurface flow constructed wetland mesocosms in enhancing nutrient removal from municipal wastewater in warm tropical environments.

    Science.gov (United States)

    Bateganya, Najib Lukooya; Kazibwe, Alex; Langergraber, Guenter; Okot-Okumu, James; Hein, Thomas

    2016-01-01

    Nutrient-rich effluents from municipal wastewater treatment plants (WWTPs) have significantly contributed to eutrophication of surface waters in East Africa. We used vertical (VF, 0.2 m(2)) and horizontal (HF, 0.45 m(2)) subsurface flow (SSF) constructed wetland (CW) configurations to design single-stage mesocosms planted with Cyperus papyrus, and operating under batch hydraulic loading regime (at a mean organic loading rate of 20 g COD m(-2) d(-1) for HF and 77 g COD m(-2) d(-1) for VF beds). The aim of the investigation was to assess the performance of SSF CWs as hotspots of nutrient transformation and removal processes between the WWTP and the receiving natural urban wetland environment in Kampala, Uganda. C. papyrus coupled with batch loading enhanced aerobic conditions and high efficiency regarding the elimination of suspended solids, organic matter, and nutrients with significant performance (P < .05) in VF mesocosms. The mean N and P elimination rates (g m(-2) d(-1)) were 9.16 N and 5.41 P in planted VF, and 1.97 N and 1.02 P in planted HF mesocosms, respectively. The lowest mean nutrient elimination rate (g m(-2) d(-1)) was 1.10 N and 0.62 P found in unplanted HF controls. Nutrient accumulation in plants and sediment retention were found to be essential processes. It can be concluded that whereas the SSF CWs may not function as independent treatment systems, they could be easily adopted as flexible and technologically less intensive options at a local scale, to increase the resilience of receiving environments by buffering peak loads from WWTPs. PMID:26387557

  19. Biological nitrogen removal using a submerged membrane bioreactor system

    International Nuclear Information System (INIS)

    A pilot-scale study was conducted using ZenoGem hollow-fiber microfiltration membrane bioreactor system to investigate the performance of membrane bioreactor process to remove nitrogen from primary effluent at a municipal wastewater treatment plant. Different operating conditions were examined by varying hydraulic retention time (HRT) and sludge retention time (SRT) between 5-8 h and 20-50 days, respectively. In addition, a series of laboratory batch tests were performed to measure the biodegradation kinetic and stoichiometric parameters under the conditions consistent with the pilot testing. The results showed that the process achieved removal efficiencies of 80-98% for COD, 93%-99% for BOD5, and 70-93% for nitrogen. The efficiency and kinetics of COD and nitrogen removal would change greatly from one operating condition to another. However, the measured kinetic parameters still fell within the typical range of those reported in the literature using Activated Sludge Models (ASM)

  20. Nutrient removal by NF and RO membranes in a decentralized sanitation system

    NARCIS (Netherlands)

    Voorthuizen, van Ellen M.; Zwijnenburg, Arie; Wessling, Matthias

    2005-01-01

    Decentralized treatment of domestic wastewater offers the possibility of water and nutrient reuse. In a decentralized sanitation system the household wastewater streams are separated in a large diluted stream (gray water) and a small and concentrated stream (black water) containing important nutrien

  1. Separating physical and biological nutrient retention and quantifying uptake kinetics from ambient to saturation in successive mountain stream reaches

    Science.gov (United States)

    Covino, Timothy; McGlynn, Brian; Baker, Michelle

    2010-12-01

    Hydrological and biogeochemical processes in stream reaches impact the downstream transport of nutrients. The output from one stream reach becomes the input for the next, leading to serial processing along stream networks. The shape of the uptake-concentration curve for each reach indicates in-stream biological uptake of nutrient. Combined with physical retention due to hydrologic turnover, both biological and physical retention will control nutrient export downstream. We performed an instantaneous addition of conservative (chloride, Cl) and nonconservative nutrient (nitrate-nitrogen, NO3-N) tracers to ascertain the relative roles of physical and biological retention across four adjacent reaches along a 3744 m stream network in the Sawtooth Mountains, ID. Physical retention dominated total retention ranging from 15% to 58% across individual reaches and totaling 81% across the entire stream length. Within each reach, biological uptake was strongly controlled by nutrient concentration. We quantified continuous Michaelis-Menten (M-M) kinetic curves for each reach and determined that ambient uptake (Uamb) ranged from 19 to 58 μg m-2 min-1, maximum uptake (Umax) from 65 to 240 μg m-2 min-1, and half-saturation constants (Km) from 4.2 to 14.4 μg l-1 NO3-N. Biological retention capacity indicated by Umax decreased in a downstream direction. Although biological retention capacity decreased moving downstream, it did not decrease as much as physical retention, which led to biological retention comprising a larger portion of total retention at downstream reaches. We suggest that accurate assessment of total retention across stream reaches and stream networks requires quantification of physical retention and the concentration-dependent nature of biological uptake.

  2. BIOLOGICAL TREATING TECHNOLOGY TO REMOVE PHENOLS IN FCCU EFFLUENT

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Baesd on the survey in 1997 fiscal year, we have been making a further survey and study together with 中国石油(Petro China) at Liaohe Refinery since 1998 fiscal year, aiming at the transfer of Japanese waste water treating technologies to China.   Scope is as follows:   (1) Demonstration of a new waste water treating technology, a kind of biological treating methods (Fluidized bed biological treatment), to eliminate phenols in FCCU effluent.   (2) Recommendation of eliminating pollutant and reducing total effluent by improving the operation.    1 Fluidized bed biological treatment 1.1 What is fluidized bed biological treatment   Fluidized bed biological treatment is the process to treat waste water as follows:   (1) To put biologically inert granular matters (fluidized carrier) into an aeration tank;   (2) Homogeneously and entirely to fluidize the particles in the tank to form highly active biofilm on the surface of each particle;   (3) To contact organic substances with these microorganisms to purify the waste water.   The surface area of the particle per unit volume is about ten times as large as that in conventional biofilm treatment process. In addition, no blockade of the filler (carrier) may be caused. Accordingly, volumetric loading of the aeration tank can be improved to attain highly efficient treatment.

  3. Macrophytes may not contribute significantly to removal of nutrients, pharmaceuticals, and antibiotic resistance in model surface constructed wetlands.

    Science.gov (United States)

    Cardinal, Pascal; Anderson, Julie C; Carlson, Jules C; Low, Jennifer E; Challis, Jonathan K; Beattie, Sarah A; Bartel, Caitlin N; Elliott, Ashley D; Montero, Oscar F; Lokesh, Sheetal; Favreau, Alex; Kozlova, Tatiana A; Knapp, Charles W; Hanson, Mark L; Wong, Charles S

    2014-06-01

    Outdoor shallow wetland mesocosms, designed to simulate surface constructed wetlands to improve lagoon wastewater treatment, were used to assess the role of macrophytes in the dissipation of wastewater nutrients, selected pharmaceuticals, and antibiotic resistance genes (ARGs). Specifically, mesocosms were established with or without populations of Typha spp. (cattails), Myriophyllum sibiricum (northern water milfoil), and Utricularia vulgaris (bladderwort). Following macrophyte establishment, mesocosms were seeded with ARG-bearing organisms from a local wastewater lagoon, and treated with a single pulse of artificial municipal wastewater with or without carbamazepine, clofibric acid, fluoxetine, and naproxen (each at 7.6μg/L), as well as sulfamethoxazole and sulfapyridine (each at 150μg/L). Rates of pharmaceutical dissipation over 28d ranged from 0.073 to 3.0d(-1), corresponding to half-lives of 0.23 to 9.4d. Based on calculated rate constants, observed dissipation rates were consistent with photodegradation driving clofibric acid, naproxen, sulfamethoxazole, and sulfapyridine removal, and with sorption also contributing to carbamazepine and fluoxetine loss. Of the seven gene determinants assayed, only two genes for both beta-lactam resistance (blaCTX and blaTEM) and sulfonamide resistance (sulI and sulII) were found in sufficient quantity for monitoring. Genes disappeared relatively rapidly from the water column, with half-lives ranging from 2.1 to 99d. In contrast, detected gene levels did not change in the sediment, with the exception of sulI, which increased after 28d in pharmaceutical-treated systems. These shallow wetland mesocosms were able to dissipate wastewater contaminants rapidly. However, no significant enhancement in removal of nutrients or pharmaceuticals was observed in mesocosms with extensive aquatic plant communities. This was likely due to three factors: first, use of naïve systems with an unchallenged capacity for nutrient assimilation and

  4. Soil strength and maize yield after topsoil removal and application of nutrient amendments on a gravelly Alfisol toposequence

    International Nuclear Information System (INIS)

    Vast areas of degraded soils exist in southwestern Nigeria due to topsoil removal by soil erosion and gravel/stone mining operators. The restoration of such soils has become imperative to sustain food production in most rural communities. Therefore, a factorial field experiment was designed in 2003 and 2004 with the factors being slope positions (upper and lower slopes), topsoil removal (0, 15 and 25 cm depths) and nutrient amendments (0, 10 t ha-1 poultry manure and 60:30:30 N: P2O5: K2O as NPK + urea). This was complemented with a laboratory study to determine the effects of soil water, gravel concentration and gravel size on soil strength. Maize was planted. Soil strength was measured with a self-recoding penetrometer at soil depth interval of 2.5 cm up to 50 cm depth. Soil bulk density, water content, maize root and shoot biomass and grain yield were measured. In the laboratory, soil strength decreased from 483-314 kPa as water content increased from 0.05-0.62 cm3 cm-3 while it increased from 294-469 kPa as gravel concentration increased from 100-500 g kg-1. Soil strength was affected more by water content and gravel concentration than gravel size. Under various moist conditions in the field, soil strength increased with soil depth from 1177-5000 kPa at the upper slope and from 526-5000 kPa at the lower slope. Thus, the lower slope had significantly lower soil strength than the upper slope. Soil strength increased with increasing soil depth removal and was significantly reduced by poultry manure. For the 2 years of study, high grain yields were sustained with poultry manure/no topsoil removal (1784-3571 kg ha-1) and NPK + urea/no topsoil removal (2371-2600 kPa) at the lower slope. However, soil at the upper slope was more resistant to degradation as 16-67% loss in yield was observed compared to 65-75% for lower slope when no nutrients were applied. Nonetheless, both the upper and lower slope positions were productive with the application of poultry manure

  5. Population dynamics in wastewater treatment plants with enhanced biological phosphorus removal operated with and without nitrogen removal

    DEFF Research Database (Denmark)

    Lee, N.; Jansen, J.l.C.; Aspegren, H.;

    2002-01-01

    to the pilot plant was periodically manipulated by external addition of phosphorus (P), acetate and glucose, respectively. The population dynamics and the in situ physiology were monitored by quantitative fluorescence in situ hybridization (FISH) and microautoradiography. Significant P removal was observed......The population dynamics of activated sludge in a pilot plant with two activated sludge systems, both designed for enhanced biological phosphorus removal (EBPR), but one of them with (BNP) and the other without (BP) nitrogen removal, was monitored during a period of 2.5 years. The influent water...... Proteobacteria (part of them Rhodocyclus-related, the identity of the rest unknown) and the Actinobacteria. However, not all of the Rhodocyclus-related bacteria showed 33Pi uptake. The P removal in the investigated plants is thus believed to be mediated by a mixed population consisting of a part...

  6. State Estimation for a Biological Phosphorus Removal Process using an Asymptotic Observer

    DEFF Research Database (Denmark)

    Larose, Claude Alain; Jørgensen, Sten Bay

    2001-01-01

    This study investigated the use of an asymptotic observer for state estimation in a continuous biological phosphorus removal process. The estimated states are the concentration of heterotrophic, autotrophic, and phosphorus accumulating organisms, polyphosphate, glycogen and PHA. The reaction scheme...

  7. Impact of nitrite on aerobic phosphorus uptake by poly-phosphate accumulating organisms in enhanced biological phosphorus removal sludges.

    Science.gov (United States)

    Zeng, Wei; Li, Boxiao; Yang, Yingying; Wang, Xiangdong; Li, Lei; Peng, Yongzhen

    2014-02-01

    Impact of nitrite on aerobic phosphorus (P) uptake of poly-phosphate accumulating organisms (PAOs) in three different enhanced biological phosphorus removal (EBPR) systems was investigated, i.e., the enriched PAOs culture fed with synthetic wastewater, the two lab-scale sequencing batch reactors (SBRs) treating domestic wastewater for nutrient removal through nitrite-pathway nitritation and nitrate-pathway nitrification, respectively. Fluorescence in situ hybridization results showed that PAOs in the three sludges accounted for 72, 7.6 and 6.5% of bacteria, respectively. In the enriched PAOs culture, at free nitrous acid (FNA) concentration of 0.47 × 10(-3) mg HNO₂-N/L, aerobic P-uptake and oxidation of intercellular poly-β-hydroxyalkanoates were both inhibited. Denitrifying phosphorus removal under the aerobic conditions was observed, indicating the existence of PAOs using nitrite as electron acceptor in this culture. When the FNA concentration reached 2.25 × 10(-3) mg HNO2-N/L, denitrifying phosphorus removal was also inhibited. And the inhibition ceased once nitrite was exhausted. Corresponding to both SBRs treating domestic wastewater with nitritation and nitrification pathway, nitrite inhibition on aerobic P-uptake by PAOs did not occur even though FNA concentration reached 3 × 10(-3) and 2.13 × 10(-3) mg HNO₂-N/L, respectively. Therefore, PAOs taken from different EBPR activated sludges had different tolerance to nitrite. PMID:23771179

  8. REMOVAL AND LEACHING OF NUTRIENTS BY SALVIN1A MOLESTA MITCHEL AND EICHHORNIA CRASSIPES (MART. SOLMS

    Directory of Open Access Journals (Sweden)

    Y.C. WEE and H.H. YEOH

    1989-01-01

    Full Text Available Profuse growth of Eichhornia crassipes and Salvinia molesta in Singapore reservoirs required their regular manual removal as their prolonged presence can lead to deterioration in the quality of the potable water. Clearing of the reservoir catchments, together with regular removal of the weeds and dumping them away from the catchments, should, in the long term, reduce their presence in the reservoirs. Laboratory experiments showing the removal of chloride, sulphate, phosphorus and nitrate from the growing medium and the release of chloride, phosphorus and nitrate by rotting plants should convince the administrators of the benefit of proper management of the problem.

  9. Controlled biomass removal - the key parameter to achieve enhanced biological phosphorus removal in biofilm systems

    DEFF Research Database (Denmark)

    Morgenroth, E.

    1999-01-01

    ) had only a minor effect on overall phosphorus removal. Soluble components fully penetrate the biofilm at certain times during the SBBR cycle as a consequence of SBBR operation with large concentration variations over the cycle time. The limiting processes for EBPR is the efficient removal...... and intensive backwashing resulting in thin biofilms is suggested. (C) 1999 IAWQ Published by Elsevier Science Ltd. All rights reserved....

  10. Micropollutant removal from municipal wastewater: from conventional treatments to advanced biological processes

    OpenAIRE

    Margot, Jonas

    2015-01-01

    Many micropollutants present in municipal wastewater, such as pharmaceuticals and pesticides, are poorly removed in conventional wastewater treatment plants (WWTPs), and may generate adverse effects on aquatic life. The objective of this thesis was to study and develop various options to improve micropollutant removal from municipal wastewaters. Various technologies were investigated, from conventional biological treatments to advanced physico-chemical and biological processes such as ozonati...

  11. Effect of Cu(II) shock loads on shortcut biological nitrogen removal in a hybrid biofilm nitrogen removal reactor.

    Science.gov (United States)

    Yin, Jun; Xu, Hengjuan; Shen, Dongsheng; Wang, Kun; Lin, Ying

    2015-06-01

    The effect of Cu(II) shock loads on shortcut biological nitrogen removal during a continuous-flow anoxic/aerobic process was investigated using a hybrid biofilm nitrogen removal reactor. The results demonstrated that [Formula: see text]-N removal was not affected by any Cu(II) shock loads, but TN removal was inhibited by Cu(II) of shock loads of 2 and 5 mg/L, and the performance could not be recovered at 5 mg/L. Furthermore, the TN removal pathway also changed in response to Cu(II) concentrations of 2 and 5 mg/L. Denitrification is more sensitive to Cu(II) shock in SBNR processes. Examination of amoA communities using quantitative PCR showed that the abundance of AOB in the aerobic tank decreased after Cu(II) shock with 5 mg/L, which supported the observed changes in [Formula: see text]-N removal efficiency. The abundance of denitrification genes declined obviously at Cu(II) concentrations of 2 and 5 mg/L, which explained the decreased TN removal efficiency at those concentrations. PMID:25833010

  12. Riparian and Associated Habitat Characteristics Related to Nutrient Concentrations and Biological Responses of Small Streams in Selected Agricultural Areas, United States, 2003-04

    Science.gov (United States)

    Zelt, Ronald B.; Munn, Mark D.

    2009-01-01

    sampled sites. The habitat characteristics sampled within the five study units were compared statistically. Bivariate correlations between riparian habitat variables and either nutrient-chemistry or biological-response variables were examined for all sites combined, and for sites within each study area. Nutrient concentrations were correlated with the extent of riparian cropland. For nitrogen species, these correlations were more frequently at the basin scale, whereas for phosphorus, they were about equally frequent at the segment and basin scales. Basin-level extents of riparian cropland and reach-level bank vegetative cover were correlated strongly with both total nitrogen and dissolved inorganic nitrogen (DIN) among multiple study areas, reflecting the importance of agricultural land-management and conservation practices for reducing nitrogen delivery from near-stream sources. When sites lacking segment-level wetlands were excluded, the negative correlation of riparian wetland extent with DIN among 49 sites was strong at the reach and segment levels. Riparian wetland vegetation thus may be removing dissolved nutrients from soil water and shallow groundwater passing through riparian zones. Other habitat variables that correlated strongly with nitrogen and phosphorus species included suspended sediment, light availability, and antecedent water temperature. Chlorophyll concentrations in seston were positively correlated with phosphorus concentrations for all sites combined. Benthic chlorophyll was correlated strongly with nutrient concentrations in only the Delmarva study area and only in fine-grained habitats. Current velocity or hydraulic scour could explain correlation patterns for benthic chlorophyll among Georgia sites, whereas chlorophyll in seston was correlated with antecedent water temperature among Washington and Delmarva sites. The lack of any consistent correlation pattern between habitat characteristics and organic material density (ash-free dry mass)

  13. Full-Scale Implementation of a Vertical Membrane Bioreactor for Simultaneous Removal of Organic Matter and Nutrients from Municipal Wastewater

    Directory of Open Access Journals (Sweden)

    So-Ryong Chae

    2015-03-01

    Full Text Available In nutrient-sensitive estuaries, wastewater treatment plants (WWTPs are required to implement more advanced treatment methods in order to meet increasingly stringent effluent guidelines for organic matter and nutrients. To comply with current and anticipated water quality regulations and to reduce the volume of produced sludge, we have successfully developed a vertical membrane bioreactor (VMBR that is composed of anoxic (lower layer and oxic (upper layer zones in one reactor. Since 2009, the VMBR has been commercialized (Q = 1100–16,000 m3/d under the trade-name of DMBRTM for recycling of municipal wastewater in South Korea. In this study, we explore the performance and stability of the full-scale systems. As a result, it was found that the DMBRTM systems showed excellent removal efficiencies of organic substances, suspended solids (SS and Escherichia coli (E. coli. Moreover, average removal efficiencies of total nitrogen (TN and total phosphorus (TP by the DMBRTM systems were found to be 79% and 90% at 18 °C, 8.3 h HRT and 41 d SRT. Moreover, transmembrane pressure (TMP was maintained below 40 kPa at a flux of 18 L/m2/h (LMH more than 300 days. Average specific energy consumption of the full-scale DMBRTM systems was found to be 0.94 kWh/m3.

  14. Biological Removal of Phosphate Using Phosphate Solubilizing Bacterial Consortium from Synthetic Wastewater: A Laboratory Scale

    OpenAIRE

    Dipak Paul; Sankar Narayan Sinha

    2015-01-01

    Biological phosphate removal is an important process having gained worldwide attention and widely used for removing phosphorus from wastewater. The present investigation was aimed to screen the efficient phosphate solubilizing bacterial isolates and used to remove phosphate from synthetic wastewater under shaking flasks conditions. Pseudomonas sp. JPSB12, Enterobacter sp. TPSB20, Flavobacterium sp. TPSB23 and mixed bacterial consortium (Pseudomonas sp. JPSB12+Enterobacter sp. TPSB20+Flavobact...

  15. A Comparative Study of the Bacterial Community in Denitrifying and Traditional Enhanced Biological Phosphorus Removal Processes

    OpenAIRE

    Lv, Xiao-Mei; Shao, Ming-Fei; Li, Chao-Lin; Li, Ji; Gao, Xin-lei; Sun, Fei-Yun

    2014-01-01

    Denitrifying phosphorus removal is an attractive wastewater treatment process due to its reduced carbon source demand and sludge minimization potential. Two lab-scale sequencing batch reactors (SBRs) were operated in alternating anaerobic-anoxic (A-A) or anaerobic-oxic (A-O) conditions to achieve denitrifying enhanced biological phosphate removal (EBPR) and traditional EBPR. No significant differences were observed in phosphorus removal efficiencies between A-A SBR and A-O SBR, with phosphoru...

  16. Microalgal-biotechnology as a platform for an integral biogas upgrading and nutrient removal from anaerobic effluents.

    Science.gov (United States)

    Bahr, Melanie; Díaz, Ignacio; Dominguez, Antonio; González Sánchez, Armando; Muñoz, Raul

    2014-01-01

    The potential of a pilot high rate algal pond (HRAP) interconnected via liquid recirculation with an external absorption column for the simultaneous removal of H2S and CO2 from biogas using an alkaliphilic microalgal-bacterial consortium was evaluated. A bubble column was preferred as external absorption unit to a packed bed column based on its ease of operation, despite showing a comparable CO2 mass transfer capacity. When the combined HRAP-bubble column system was operated under continuous mode with mineral salt medium at a biogas residence time of 30 min in the absorption column, the system removed 100% of the H2S (up to 5000 ppmv) and 90% of the CO2 supplied, with O2 concentrations in the upgraded biogas below 0.2%. The use of diluted centrates as a free nutrient source resulted in a gradual decrease in CO2 removal to steady values of 40%, while H2S removal remained at 100%. The anaerobic digestion of the algal-bacterial biomass produced during biogas upgrading resulted in a CH4 yield of 0.21-0.27 L/gVS, which could satisfy up to 60% of the overall energy demand for biogas upgrading. This proof of concept study confirmed that algal-bacterial photobioreactors can support an integral upgrading without biogas contamination, with a net negative CO2 footprint, energy production, and a reduction of the eutrophication potential of the residual anaerobic effluents.

  17. Biological regeneration of ferric (Fe3+) solution during desulphurisation of gaseous streams: effect of nutrients and support material.

    Science.gov (United States)

    Mulopo, Jean; Schaefer, L

    2015-01-01

    This paper evaluates the biological regeneration of ferric Fe3+ solution during desulphurisation of gaseous streams. Hydrogen sulphide (H2S) is absorbed into aqueous ferric sulphate solution and oxidised to elemental sulphur, while ferric ions Fe3+ are reduced to ferrous ions Fe2+. During the industrial regeneration of Fe3+, nutrients and trace minerals usually provided in a laboratory setup are not present and this depletion of nutrients may have a negative impact on the bacteria responsible for ferrous iron oxidation and may probably affect the oxidation rate. In this study, the effect of nutrients and trace minerals on ferrous iron oxidation have been investigated and the results showed that the presence of nutrients and trace minerals affects the efficiency of bacterial Fe2+oxidation. The scanning electron microscopy analysis of the geotextile support material was also conducted and the results showed that the iron precipitate deposits appear to play a direct role on the bacterial biofilm formation. PMID:26038932

  18. The Impact of Temperature on Anaerobic Biological Perchlorate Removal and Aerobic Polishing of the Effluent

    Science.gov (United States)

    This abstract describes a pilot-scale evaluation of anaerobic biological perchlorate (C1O4) removal followed by aerobic effluent polishing. The anaerobic biological contactor operated for 3.5 years. During that period, two effluent polishing evaluations, lasting 311 an...

  19. The Impact of Temperature on Anaerobic Biological Perchlorate Removal and Aerobic Polishing of the Effluent - paper

    Science.gov (United States)

    This abstract describes a pilot-scale evaluation of anaerobic biological perchlorate (C1O4) removal followed by aerobic effluent polishing. The anaerobic biological contactor operated for 3.5 years. During that period, two effluent polishing evaluations, lasting 311 an...

  20. Nutrient availability affects pigment production but not growth in lichens of biological soil crusts

    Science.gov (United States)

    Bowker, M.A.; Koch, G.W.; Belnap, J.; Johnson, N.C.

    2008-01-01

    Recent research suggests that micronutrients such as Mn may limit growth of slow-growing biological soil crusts (BSCs) in some of the drylands of the world. These soil surface communities contribute strongly to arid ecosystem function and are easily degraded, creating a need for new restoration tools. The possibility that Mn fertilization could be used as a restoration tool for BSCs has not been tested previously. We used microcosms in a controlled greenhouse setting to investigate the hypothesis that Mn may limit photosynthesis and consequently growth in Collema tenax, a dominant N-fixing lichen found in BSCs worldwide. We found no evidence to support our hypothesis; furthermore, addition of other nutrients (primarily P, K, and Zn) had a suppressive effect on gross photosynthesis (P = 0.05). We also monitored the growth and physiological status of our microcosms and found that other nutrients increased the production of scytonemin, an important sunscreen pigment, but only when not added with Mn (P = 0.01). A structural equation model indicated that this effect was independent of any photosynthesis-related variable. We propose two alternative hypotheses to account for this pattern: (1) Mn suppresses processes needed to produce scytonemin; and (2) Mn is required to suppress scytonemin production at low light, when it is an unnecessary photosynthate sink. Although Mn fertilization does not appear likely to increase photosynthesis or growth of Collema, it could have a role in survivorship during environmentally stressful periods due to modification of scytonemin production. Thus, Mn enrichment should be studied further for its potential to facilitate BSC rehabilitation. ?? 2008 Elsevier Ltd.

  1. Enhanced biological phosphorus removal from activated sludge system; Eliminacion biologica del fosfor en aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Pidre Bocardo, J. R.; Toja Santillana, J.; Alonso Alvarez, E. [Sevilla (Spain)

    1999-06-01

    A literature review of enhanced biological phosphorus removal was performed. This biological removal is based on the selective enrichment of bacteria accumulating inorganic polyphosphate, obtained at a cyclic regime of alternating anaerobic and aerobic conditions; or anaerobic, anoxic and aerobic zones for combined nitrogen and phosphorus removal. Some bacterial groups may to be implicate in this process, the gen Acinetobacter has been the most studied. In this paper a study of phosphorate forms from wastewater for a conventional activated sludge system is presented. (Author) 40 refs.

  2. Including Life Cycle Assessment for decision-making in controlling wastewater nutrient removal systems

    DEFF Research Database (Denmark)

    Corominas, Lluís; Larsen, Henrik Fred; Flores-Alsina, Xavier;

    2013-01-01

    of the impact categories is conducted to assess how value choices (policy decisions) may affect the management of WWTPs. For the scenarios with only N-limitation, the LCA-based ranking of the control strategies is sensitive to the choice of weighting factors, whereas this is not the case for N&P or P......This paper focuses on the use of Life Cycle Assessment (LCA) to evaluate the performance of seventeen control strategies in wastewater treatment plants (WWTPs). It tackles the importance of using site-specific factors for nutrient enrichment when decision-makers have to select best operating...

  3. Ecological Limits to Terrestrial Biological Carbon Dioxide Removal

    Science.gov (United States)

    Torn, M. S.; Smith, L. J.; Mishra, U.; Sanchez, D.; Williams, J.

    2014-12-01

    Many climate change mitigation scenarios include terrestrial atmospheric carbon dioxide removal (BCDR) or carbon neutral bioenergy production through bioenergy with carbon capture and storage (BECS) or afforestation/reforestation. Very high sequestration potentials for these strategies have been reported, and we evaluate the potential ecological limits (e.g., land and resource requirements) to implementation at the 1 Pg C y-1 scale relevant to climate change mitigation for U.S. and global scenarios. We estimate that removing 1 Pg C y-1 via tropical afforestation would require at least 7×106 ha y-1 of land, 0.09 Tg y-1 of nitrogen, and 0.2 Tg y-1 of phosphorous, and would increase evapotranspiration from those lands by almost 50%. Because of improved carbon capture technologies, we are updating (and reducing) our previous estimates for switchgrass BECS (previous estimate was 2×108 ha land and 20 Tg y-1 of nitrogen (20 % of global fertilizer nitrogen production)). Miscanthus could meet the same biomass production with much lower N demand. Moreover, transitioning the U.S land currently under corn- ethanol production to no-till perennial grasses for bioenergy would meet U.S. needs and have additional environmental benefits (such as improved wildlife habitat and soil restoration). Thus, there are both signficant ecological limits to BCDR as well as potential ecological benefits, depending on implementation.

  4. A novel membrane distillation-thermophilic bioreactor system: biological stability and trace organic compound removal.

    Science.gov (United States)

    Wijekoon, Kaushalya C; Hai, Faisal I; Kang, Jinguo; Price, William E; Guo, Wenshan; Ngo, Hao H; Cath, Tzahi Y; Nghiem, Long D

    2014-05-01

    The removal of trace organic compounds (TrOCs) by a novel membrane distillation-thermophilic bioreactor (MDBR) system was examined. Salinity build-up and the thermophilic conditions to some extent adversely impacted the performance of the bioreactor, particularly the removal of total nitrogen and recalcitrant TrOCs. While most TrOCs were well removed by the thermophilic bioreactor, compounds containing electron withdrawing functional groups in their molecular structure were recalcitrant to biological treatment and their removal efficiency by the thermophilic bioreactor was low (0-53%). However, the overall performance of the novel MDBR system with respect to the removal of total organic carbon, total nitrogen, and TrOCs was high and was not significantly affected by the conditions of the bioreactor. All TrOCs investigated here were highly removed (>95%) by the MDBR system. Biodegradation, sludge adsorption, and rejection by MD contribute to the removal of TrOCs by MDBR treatment. PMID:24658107

  5. Comparison of biological and chemical phosphorus removals in continuous and sequencing batch reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ketchum, L.H.; Irvine, R.L. Jr.; Breyfogle, R.E.; Manning, J.F. Jr.

    1987-01-01

    A full-scale study of phosphorus removal has been conducted at Culver using continuous-flow operation, SBR operation, and several different chemical treatment schemes. A full-scale demonstration of SBR biological phosphorus removal also has been shown to be effective. Four contributing groups of organisms and their roles in biological SBR phosphorus removal have been described: denitrifying organisms, fermentation product-manufacturing organisms, phosphorus- accumulating organisms, and aerobic autotrophs and heterotrophs. The SBR can provide the proper balance of anoxic, anaerobic, and aerobic conditions to allow these group of organisms to successfully remove phosphorus biologically, without chemical addition. Treatment results using various chemicals for phosphorus removal, both during conventional, continuous-flow operation and after the plant was converted for SBR operation, have also been provided for comparison. Effluent phosphorus concentrations were almost identical for each period, except for the period when phosphorus was removed biologically and without any chemical addition when effluent phosphorus concentrations were the lowest. These removals were made as a result of settling alone; no tertiary rapid stand filter was used or required.

  6. Biological removal of metal ions from aqueous process streams

    International Nuclear Information System (INIS)

    Aqueous waste streams from nuclear fuel processing operations may contain trace quantities of heavy metals such as uranium. Conventional chemical and physical treatment may be ineffective or very expensive when uranium concentrations in the range of 10 to 100 g/m3 must be reduced to 1 g/m3 or less. The ability of some microorganisms to adsorb or complex dissolved heavy metals offers an alternative treatment method. Uranium uptake by Saccharomyces cerevisiae NRRL Y-2574 and a strain of Pseudomonas aeruginosa was examined to identify factors which might affect a process for the removal of uranium from wastewater streams. At uranium concentrations in the range of 10 to 500 g/m3, where the binding capacity of the biomass was not exceeded, temperature, pH, and initial uranium concentration were found to influence the rate of uranium uptake, but not the soluble uranium concentration at equilibrium. 6 figs

  7. Green-cane harvest of sugarcane effects on biomass and energy yields and nutrient removal

    Science.gov (United States)

    Sugarcane yields in Louisiana can approach 40 dry Mg ha-1, making sugarcane an attractive biofuel feedstock as well as a profitable sugar crop. Existing technology used in green-cane harvesting can be used to allow chopper harvester extractor fans to remove variable amounts of extraneous leaf materi...

  8. Simultaneous nitrogen and phosphorus removal in the sulfur cycle-associated Enhanced Biological Phosphorus Removal (EBPR) process.

    Science.gov (United States)

    Wu, Di; Ekama, George A; Wang, Hai-Guang; Wei, Li; Lu, Hui; Chui, Ho-Kwong; Liu, Wen-Tso; Brdjanovic, Damir; van Loosdrecht, Mark C M; Chen, Guang-Hao

    2014-02-01

    Hong Kong has practiced seawater toilet flushing since 1958, saving 750,000 m(3) of freshwater every day. A high sulfate-to-COD ratio (>1.25 mg SO4(2-)/mg COD) in the saline sewage resulting from this practice has enabled us to develop the Sulfate reduction, Autotrophic denitrification and Nitrification Integrated (SANI(®)) process with minimal sludge production and oxygen demand. Recently, the SANI(®) process has been expanded to include Enhanced Biological Phosphorus Removal (EBPR) in an alternating anaerobic/limited-oxygen (LOS-EBPR) aerobic sequencing batch reactor (SBR). This paper presents further development - an anaerobic/anoxic denitrifying sulfur cycle-associated EBPR, named as DS-EBPR, bioprocess in an alternating anaerobic/anoxic SBR for simultaneous removal of organics, nitrogen and phosphorus. The 211 day SBR operation confirmed the sulfur cycle-associated biological phosphorus uptake utilizing nitrate as electron acceptor. This new bioprocess cannot only reduce operation time but also enhance volumetric loading of SBR compared with the LOS-EBPR. The DS-EBPR process performed well at high temperatures of 30 °C and a high salinity of 20% seawater. A synergistic relationship may exist between sulfur cycle and biological phosphorus removal as the optimal ratio of P-release to SO4(2-)-reduction is close to 1.0 mg P/mg S. There were no conventional PAOs in the sludge. PMID:24342048

  9. 生物除磷的机理及工艺%Mechanism and Processes of Biological Phosphorus Removal

    Institute of Scientific and Technical Information of China (English)

    欧阳子民

    2011-01-01

    水体富营养化是世界性难题,其中磷是主要限制因子。生物除磷工艺具有结构简单、污泥产量少、运行费用较低、便于操作和磷的回收等优点。在介绍PAO和DPB除磷原理的基础上,综述国内外生物除磷的研究进展,并介绍应用较多的除磷工艺,以供污水防治参考。%The phosphorus is the limited nutrient in eutrophication of the waterbody,which is a significant worldwide problem. The process of biological removal of phosphorus in waterbody is structure simple, sludge production less,low-cost,convenient in operation and reelaimation. Based on the introduction of the mechanism of PAO and DPB ,the updated progresses and processes in biological removal of phosphorus in waterbody were summarized in this paper, so as to provide references for the control of waste water.

  10. A new hybrid treatment system of bioreactors and electrocoagulation for superior removal of organic and nutrient pollutants from municipal wastewater.

    Science.gov (United States)

    Nguyen, Dinh Duc; Ngo, Huu Hao; Yoon, Yong Soo

    2014-02-01

    This paper evaluated a novel pilot scale hybrid treatment system which combines rotating hanging media bioreactor (RHMBR), submerged membrane bioreactor (SMBR) along with electrocoagulation (EC) as post treatment to treat organic and nutrient pollutants from municipal wastewater. The results indicated that the highest removal efficiency was achieved at the internal recycling ratio as 400% of the influent flow rate which produced a superior effluent quality with 0.26mgBOD5L(-1), 11.46mgCODCrL(-1), 0.00mgNH4(+)-NL(-1), and 3.81mgT-NL(-1), 0.03mgT-PL(-1). During 16months of operation, NH4(+)-N was completely eliminated and T-P removal efficiency was also up to 100%. It was found that increasing in internal recycling ratio could improve the nitrate and nitrogen removal efficiencies. Moreover, the TSS and coliform bacteria concentration after treatment was less than 5mgL(-1) and 30MPNmL(-1), respectively, regardless of internal recycling ratios and its influent concentration.

  11. Microalgae consortia cultivation in dairy wastewater to improve the potential of nutrient removal and biodiesel feedstock production.

    Science.gov (United States)

    Qin, Lei; Wang, Zhongming; Sun, Yongming; Shu, Qing; Feng, Pingzhong; Zhu, Liandong; Xu, Jin; Yuan, Zhenhong

    2016-05-01

    The potential of microalgae consortia used in dairy wastewater treatment combined with microalgae biodiesel feedstock production was evaluated by comparing the nutrient removal of dairy wastewater, the growth of cells, and the lipid content and composition of biomass between monoalgae and microalgae consortia cultivation system. Our results showed that higher chemical oxygen demand (COD) removal (maximum, 57.01-62.86 %) and total phosphorus (TP) removal (maximum, 91.16-95.96 %) were achieved in almost microalgae consortia cultivation system than those in Chlorella sp. monoalgae cultivation system (maximum, 44.76 and 86.74 %, respectively). In addition, microalgae consortia cultivation except the mixture of Chlorella sp. and Scenedesmus spp. reached higher biomass concentration (5.11-5.41 g L(-1)), biomass productivity (730.4-773.2 mg L(-1) day(-1)), and lipid productivity (143.7-150.6 mg L(-1) day(-1)) than those of monoalgae cultivation (4.72 g L(-1), 674.3, and 142.2 mg L(-1) day(-1), respectively) on the seventh day. Furthermore, the fatty acid methyl ester (FAME) profiles indicated the lipids produced from microalgae consortia cultivation system were more suitable for biodiesel production. The microalgae consortia display superiority in dairy wastewater treatment and the getting feedstock for biodiesel production. PMID:26780059

  12. Control Structure Design of an Innovative Enhanced Biological Nutrient Recovery Activated Sludge System Coupled with a Photobioreactor

    DEFF Research Database (Denmark)

    Valverde Perez, Borja; Fuentes-Martínez, José Manuel; Flores Alsina, Xavier;

    2015-01-01

    The TRENS system is a train of biological units designed for resource recovery from wastewater. It is a sequence of a modified enhanced biological phosphorus removal and recovery system (EBP2R) coupled with a photobioreactor (PBR). The bacteria-based system constructs an optimal culture media for...

  13. The removal of concrete layers from biological shields by microwaves

    International Nuclear Information System (INIS)

    Concrete blocks reinforced with steel bars have been subjected to microwave attack at a frequency of 896 MHz at power levels up to 25 kW. The surface concrete has been explosively removed to the depth of the reinforcement, 10 cm, at a rate of about 2 litres per kWh. Heating was localized around the point of attack, with temperatures up to 3000C at the fractured face being attained. A simple mathematical model of the propagation and absorption of micro-waves was used to estimate the temperature rise of concrete at microwave frequencies of 896 wand 2450 MHz, at different power levels with and without the presence of reinforcing bars. This demonstrated that reinforcement is expected to significantly increase the temperature rise in the concrete between the irradiated surface and the reinforcement, and that near-surface heating should be more rapid at the higher frequency. There was reasonable agreement between predicted and observed temperature at the higher power levels. Further desk and laboratory studies are proposed before proceeding to a fullscale practical demolition machine and the requirements for a prototype remotely-operated demonstration system have been identified. This consists of a static generator of high power (at least 50 kW) transmitting microwaves via a steerable waveguide to a remote applicator mounted on a simple three-axis manipulator capable of traversing realistically large concrete test panels

  14. Scenario Analysis of Nutrient Removal from Municipal Wastewater by Microalgal Biofilms

    OpenAIRE

    Wijffels, René H.; Nadine C. Boelee; Marcel Janssen; Hardy Temmink; Buisman, Cees J. N.

    2012-01-01

    Microalgae can be used for the treatment of municipal wastewater. The application of microalgal biofilms in wastewater treatment systems seems attractive, being able to remove nitrogen, phosphorus and COD from wastewater at a short hydraulic retention time. This study therefore investigates the area requirement, achieved effluent concentrations and biomass production of a hypothetical large-scale microalgal biofilm system treating municipal wastewater. Three scenarios were defined: using micr...

  15. Scenario Analysis of Nutrient Removal from Municipal Wastewater by Microalgal Biofilms

    Directory of Open Access Journals (Sweden)

    René H. Wijffels

    2012-04-01

    Full Text Available Microalgae can be used for the treatment of municipal wastewater. The application of microalgal biofilms in wastewater treatment systems seems attractive, being able to remove nitrogen, phosphorus and COD from wastewater at a short hydraulic retention time. This study therefore investigates the area requirement, achieved effluent concentrations and biomass production of a hypothetical large-scale microalgal biofilm system treating municipal wastewater. Three scenarios were defined: using microalgal biofilms: (1 as a post-treatment; (2 as a second stage of wastewater treatment, after a first stage in which COD is removed by activated sludge; and (3 in a symbiotic microalgal/heterotrophic system. The analysis showed that in the Netherlands, the area requirements for these three scenarios range from 0.32 to 2.1 m2 per person equivalent. Moreover, it was found that it was not possible to simultaneously remove all nitrogen and phosphorus from the wastewater, because of the nitrogen:phosphorus ratio in the wastewater. Phosphorus was limiting in the post-treatment scenario, while nitrogen was limiting in the two other scenarios. Furthermore, a substantial amount of microalgal biomass was produced, ranging from 13 to 59 g per person equivalent per day. These findings show that microalgal biofilm systems hold large potential as seasonal wastewater treatment systems and that it is worthwhile to investigate these systems further.

  16. Investigation into ammonia stress on Cyperus alternifolius and its impact on nutrient removal in microcosm experiments.

    Science.gov (United States)

    Tao, Wendong; Han, Jianqiu; Li, Hanyan

    2015-11-01

    Ammonia stress on plants has been investigated at discrete ammonia concentrations in constructed wetlands. This study introduced a Gaussian model to simulate the kinetics of ammonia stress and investigated reversible and irreversible ammonia stress on Cyperus alternifolius in wetland-like microcosms. Ammonia stress on plant weight increase and oxygen release potential started at weekly ammonia concentrations of 27 and 28 mg N/L, reached 50% inhibition at 178 and 158 mg N/L, and resulted in lethal effects at 311 and 303 mg N/L, respectively. The stress of one-time ammonia concentrations up to 400 mg N/L could be reversible. Ammonia concentrations constantly above 219 mg N/L exerted irreversible stress. In the microcosms with ammonia concentrations above the 50% inhibition levels, plants played a minor role in nitrogen removal. Nitrogen removal performance was not affected considerably by ammonia stress. Orthophosphate removal was suppressed by ammonia stress due to less plant uptake. Design and operation of constructed wetlands should consider wastewater ammonia concentration so that the integrity of constructed wetland ecosystems can be maintained.

  17. Changes in nutrient profile of soil subjected to bioleaching for removal of heavy metals using Acidithiobacillus thiooxidans

    Energy Technology Data Exchange (ETDEWEB)

    NareshKumar, R. [Centre for Environmental Studies, Anna University, Chennai 600025 (India)], E-mail: nareshkrish@hotmail.com; Nagendran, R. [Centre for Environmental Studies, Anna University, Chennai 600025 (India)

    2008-08-15

    Studies were carried out to assess changes in nitrogen, phosphorus and potassium contents in soil during bioleaching of heavy metals from soil contaminated by tannery effluents. Indigenous sulfur oxidizing bacteria Acidithiobacillus thiooxidans isolated from the contaminated soil were used for bioremediation. Solubilization efficiency of chromium, cadmium, copper and zinc from soil was 88, 93, 92 and 97%, respectively. However, loss of nitrogen, phosphorus and potassium from the soil was 30, 70 and 68%, respectively. These findings indicate that despite its high potential for removal of heavy metals from contaminated soils, bioleaching results in undesirable dissolution/loss of essential plant nutrients. This aspect warrants urgent attention and detailed studies to evaluate the appropriateness of the technique for field application.

  18. Changes in nutrient profile of soil subjected to bioleaching for removal of heavy metals using Acidithiobacillus thiooxidans.

    Science.gov (United States)

    NareshKumar, R; Nagendran, R

    2008-08-15

    Studies were carried out to assess changes in nitrogen, phosphorus and potassium contents in soil during bioleaching of heavy metals from soil contaminated by tannery effluents. Indigenous sulfur oxidizing bacteria Acidithiobacillus thiooxidans isolated from the contaminated soil were used for bioremediation. Solubilization efficiency of chromium, cadmium, copper and zinc from soil was 88, 93, 92 and 97%, respectively. However, loss of nitrogen, phosphorus and potassium from the soil was 30, 70 and 68%, respectively. These findings indicate that despite its high potential for removal of heavy metals from contaminated soils, bioleaching results in undesirable dissolution/loss of essential plant nutrients. This aspect warrants urgent attention and detailed studies to evaluate the appropriateness of the technique for field application.

  19. Changes in nutrient profile of soil subjected to bioleaching for removal of heavy metals using Acidithiobacillus thiooxidans

    International Nuclear Information System (INIS)

    Studies were carried out to assess changes in nitrogen, phosphorus and potassium contents in soil during bioleaching of heavy metals from soil contaminated by tannery effluents. Indigenous sulfur oxidizing bacteria Acidithiobacillus thiooxidans isolated from the contaminated soil were used for bioremediation. Solubilization efficiency of chromium, cadmium, copper and zinc from soil was 88, 93, 92 and 97%, respectively. However, loss of nitrogen, phosphorus and potassium from the soil was 30, 70 and 68%, respectively. These findings indicate that despite its high potential for removal of heavy metals from contaminated soils, bioleaching results in undesirable dissolution/loss of essential plant nutrients. This aspect warrants urgent attention and detailed studies to evaluate the appropriateness of the technique for field application

  20. Optimizing cultivation strategies for robust algal growth and consequent removal of inorganic nutrients in pretreated livestock effluent.

    Science.gov (United States)

    Kim, Hyun-Chul; Choi, Wook Jin; Ryu, Jun Hee; Maeng, Sung Kyu; Kim, Han Soo; Lee, Byung-Chan; Song, Kyung Guen

    2014-10-01

    Dilution was employed as a pretreatment strategy to increase light transmittance and decrease ammonia toxicity in piggery effluent prior to the cultivation of microalgae. The dilution effect was quantitatively determined based on both the maximum specific nutrient consumption rate and the maximum growth coefficient to minimize the usage of diluent. The biomass productivity of microalgae was also evaluated to select the best species among the five different candidates examined. A 20-fold dilution of piggery wastewater resulted in decreased chromaticity (584 mg Pt-Co L(-1)) and total nitrogen (76 mg L(-1)), on which the microalgae cultivation was more effective for an algal growth compared to the other dilution factors. If the initial cell concentration of Scenedesmus quadricauda increased, the production of biomass tended to improve. Robust growth and harvesting of S. quadricauda were achieved, and the associated consistent removal of inorganic nutrients was accomplished during the semi-continuous cultivation of the best species. PMID:25138601

  1. Treatment of sludge containing nitro-aromatic compounds in reed-bed mesocosms - Water, BOD, carbon and nutrient removal.

    Science.gov (United States)

    Gustavsson, L; Engwall, M

    2012-01-01

    Since the mid-1970s, Sweden has been depositing 1 million ton d.w sludge/year, produced at waste water treatment plants. Due to recent legislation this practice is no longer a viable method of waste management. It is necessary to improve existing and develop new sludge management techniques and one promising alternative is the dewatering and treatment of sludge in constructed wetlands. The aim of this study was to follow reduction of organic carbon, BOD and nutrients in an industrial sludge containing nitro-aromatic compounds passing through constructed small-scale wetlands, and to investigate any toxic effect such as growth inhibition of the common reed Phragmites australis. The result showed high reduction of all tested parameters in all the outgoing water samples, which shows that constructed wetlands are suitable for carbon and nutrient removal. The results also showed that P. australis is tolerant to xenobiotics and did not appear to be affected by the toxic compounds in the sludge. The sludge residual on the top of the beds contained low levels of organic carbon and is considered non-organic and could therefore be landfilled. Using this type of secondary treatment method, the amount of sludge could be reduced by 50-70%, mainly by dewatering and biodegradation of organic compounds.

  2. Influence of Silver nanoparticles on nutrient removal and microbial communities in SBR process after long-term exposure.

    Science.gov (United States)

    Zhang, Zhaohan; Gao, Peng; Li, Moqing; Cheng, Jiaqi; Liu, Wei; Feng, Yujie

    2016-11-01

    The widespread utilization of silver nanoparticles (AgNPs) in industrial and commercial products inevitably raises the release into wastewater that might cause potential negative impacts on sewage treatment system. In this paper, long-term exposure experiments at four levels were conducted to determine whether AgNPs caused adverse impacts on nutrient removals in sequencing batch reactors (SBRs) and changes of microbial community structure. Compared with the control reactor (without AgNPs), carbon, nitrogen and phosphorus removal in presence of 0.1mg/L AgNPs was no difference. However, presence of 1.0 and 10mg/L AgNPs decreased the average removal efficiencies of COD from 95.4% to 85.2% and 68.3%, ammonia nitrogen from 98.8% to 71.2% and 49%, SOP from 97.6% to 75.5% and 54.1%, respectively. It was found that AgNPs could accumulate in sludge with the distribution coefficients of 39.2-114L/g, inhibit the protein and polysaccharide production in EPS, reduce the SOUR of sludge, and greatly increase LDH release from microbial cells. The illumina high-throughput sequencing results indicated that AgNPs concentration changed the structures of bacterial communities, associating with the effects of AgNPs on reactor performance. Sequence analyses showed that Proteobacteria, Bacteroidetes and Acidobacteria were the dominant phyla. It was notable that AgNPs addition reduced the contents of several nitrifying bacteria at genera level in sludge, leading to the lower removal of nitrogen. PMID:27343942

  3. Nutrients removal by Typha latifolia and Cynodon spp. grown in constructed wetlands

    Directory of Open Access Journals (Sweden)

    Mateus Pimentel de Matos

    2011-04-01

    Full Text Available The objective of this study was to evaluate the extraction capacity of two species when grown in constructed wetlands with subsurface horizontal flow (SACs for the treatment of swine wastewater (ARS. To this end, were built 8 SACs of 2.0 m x 0.5 m x 0.6 m, fiber glass, filled with 0.55 m of fine gravels. In SAC2; SAC4; SAC6 and SAC8 was cultivated cattail (Typha latifolia and in SAC3; SAC5; SAC7 and SAC9 was cultivated tifton-85 bermudagrass (Cynodon spp.. The SAC2 and SAC3, SAC4 and SAC5, SAC6 and SAC7 and SAC8 and SAC9 received 163, 327, 461 and 561 kg ha-1 day-1 of BOD, respectively. During the 120 days of the SACs monitoring, it was found that the cattail has not adapted to the conditions of exposure. The highest yields were obtained with the application of organic load average of 327 kg ha-1 day-1 of BOD. The tifton-85 was the plant species with the highest capacity to extract nutrients, getting to draw between 443 and 540, 86 and 99, 193 and 241, 0.77 and 2.17, and 1.21 and 3.68 kg ha-1 TKN, P, K, Cu and Zn, respectively, while cattail showed greater capacity to absorb sodium.

  4. Enhanced biological phosphorus removal in the wastewater treatment plant of Bunnik

    Energy Technology Data Exchange (ETDEWEB)

    Vries, H.P. de; Rensink, J.H.

    1989-02-01

    At several sewage treatment plants in the Netherlands there has been continuously found a remarkable high phosphorus removal rate, without using chemical additions. In Bunnik this is up to 90%. In the effluent we will mostly find less than 1 mg P/l. At the Bunnik plant we deal with biological excess phosphorus removal. Biological phosphorus removal is based on the luxury uptake of phosphorus by some bacteria. On certain circumstances micro-organisms of the genius Acinetobacter stored excess amounts of phosphates in their cells. In 1984 a project started, financed by the institute for inland waters and wastewater treatment (DBW/RIZA). The purpose of this research project was to find factors which were, responsible for the remarkable enhanced phosphorus removal in the Bunnik plant.

  5. Particle size distribution and removal in the chemical-biological flocculation process

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-bin; ZHAO Jian-fu; XIA Si-qing; LIU Chang-qing; KANG Xing-sheng

    2007-01-01

    The particle characterization from the influent and effluent of a chemical-biological flocculation (CBF) process was studied with a laser diffraction device. Water samples from a chemically enhanced primary treatment (CEPT) process and a primary sediment tank process were also analyzed for comparison. The results showed that CBF process was not only effective for both the big size particles and small size particles removal, but also the best particle removal process in the three processes. The results also indicated that CBF process was superior to CEPT process in the heavy metals removal. The high and non-selective removal for heavy metals might be closely related to its strong ability to eliminate small particles. Samples from different locations in CBF reactors showed that small particles were easier to aggregate into big ones and those disrupted flocs could properly flocculate again along CBF reactor because of the biological flocculation.

  6. Removal of disinfection by-product formation potentials by biologically assisted GAC treatment

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The object of this paper is to evaluate the removal of disinfection by-products formation potential by artificially intensified biological activated carbon(BAC) process which is developed on the basis of traditional ozone granular activated carbon (GAC). The results show that 23.1% of trihalomethane formation potential (THMFP) and 68% of haloacetic acid formation potential (HAAFP) can be removed by BAC,respectively. Under the same conditions, the removal rates of the same substances were 12.2% and 13-25 % respectively only by GAC process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. BAC process has some advantages such as long backwashing cycle time, low backwashing intensity and prolonged activated carbon lifetime, etc.

  7. Full-scale biological phosphorus removal: quantification of storage polymers, microbial performance and metabolic modelling

    OpenAIRE

    Lanham, Ana Alexandra Barbosa

    2012-01-01

    Enhanced biological phosphorus removal (EBPR) can be applied in wastewater treatment plants (WWTPs), as a sustainable and efficient way to remove phosphorus from wastewater and hence reduce its impact on eutrophication. This work characterises the performance, metabolism and identity of the microbial EBPR communities in full-scale WWTPs. The accurate quantification of the internal storage compounds, namely polyhydroxyalkanoate (PHA) and glycogen, is crucial to the characterisat...

  8. Biological phosphorus removal during high-rate, low-temperature, anaerobic digestion of wastewater

    OpenAIRE

    Ciara eKeating; Chin, Jason P.; Dermot eHughes; Panagiotis eManesiotis; Denise eCysneiros; Therese eMahony; Smith, Cindy J; John W McGrath; Vincent eO'Flaherty

    2016-01-01

    We report, for the first time, extensive biologically-mediated phosphate removal from wastewater during high-rate anaerobic digestion (AD). A hybrid sludge bed/fixed-film (packed pumice stone) reactor was employed for low-temperature (12°C) anaerobic treatment of synthetic sewage wastewater. Successful phosphate removal from the wastewater (up to 78% of influent phosphate) was observed, mediated by biofilms in the reactor. Scanning electron microscopy and energy dispersive X-ray analysis reve...

  9. A metagenome of a full-scale microbial community carrying out enhanced biological phosphorus removal

    OpenAIRE

    Albertsen, Mads; Hansen, Lea Benedicte Skov; Saunders, Aaron Marc; Nielsen, Per Halkjær; Nielsen, Kåre Lehmann

    2011-01-01

    Enhanced biological phosphorus removal (EBPR) is widely used for removal of phosphorus from wastewater. In this study, a metagenome (18.2 Gb) was generated using Illumina sequencing from a full-scale EBPR plant to study the community structure and genetic potential. Quantitative fluorescence in situ hybridization (qFISH) was applied as an independent method to evaluate the community structure. The results were in qualitative agreement, but a DNA extraction bias against gram positive bacteria ...

  10. Integrative microbial community analysis reveals full-scale enhanced biological phosphorus removal under tropical conditions

    OpenAIRE

    Yingyu Law; Rasmus Hansen Kirkegaard; Angel Anisa Cokro; Xianghui Liu; Krithika Arumugam; Chao Xie; Mikkel Stokholm-Bjerregaard; Drautz-Moses, Daniela I.; Per Halkjær Nielsen; Stefan Wuertz; Rohan B. H. Williams

    2016-01-01

    Management of phosphorus discharge from human waste is essential for the control of eutrophication in surface waters. Enhanced biological phosphorus removal (EBPR) is a sustainable, efficient way of removing phosphorus from waste water without employing chemical precipitation, but is assumed unachievable in tropical temperatures due to conditions that favour glycogen accumulating organisms (GAOs) over polyphosphate accumulating organisms (PAOs). Here, we show these assumptions are unfounded b...

  11. Biological Phosphorus Removal During High-Rate, Low-Temperature, Anaerobic Digestion of Wastewater

    OpenAIRE

    Keating, Ciara; Chin, Jason P.; Hughes, Dermot; Manesiotis, Panagiotis; Cysneiros, Denise; Mahony, Therese; Smith, Cindy J; John W McGrath; O’Flaherty, Vincent

    2016-01-01

    We report, for the first time, extensive biologically mediated phosphate removal from wastewater during high-rate anaerobic digestion (AD). A hybrid sludge bed/fixed-film (packed pumice stone) reactor was employed for low-temperature (12°C) anaerobic treatment of synthetic sewage wastewater. Successful phosphate removal from the wastewater (up to 78% of influent phosphate) was observed, mediated by biofilms in the reactor. Scanning electron microscopy and energy dispersive X-ray analysis reve...

  12. Biological removal of phosphorus and nitrogen from wastewater : new insights from metagenomic and metatranscriptomic approaches

    OpenAIRE

    Mao, Yanping; 毛艷萍

    2014-01-01

    The study was conducted to reveal the insights of microbial diversity, functional profile and gene expression of microorganisms responsible for enhanced biological phosphorus removal (EBPR) and hydrogen-oxidizing autotrophic denitrification mainly by using metagenomic and metatranscriptomic analysis based on high-throughput sequencing. Two sequencing batch reactors (SBRs) were operated to remove phosphorus (15 mg/L) from synthetic wastewater. The integrated metagenomic and metatranscripto...

  13. Application of chemical oxidation processes for the removal of pharmaceuticals in biologically treated wastewater

    OpenAIRE

    Hey, Gerly

    2013-01-01

    The discharge of effluents from wastewater treatment plants (WWTPs) is considered to be the major source of residual pharmaceuticals frequently found in aquatic environments. The complex nature of such compounds tends to make conventional biological treatments aimed at their removal ineffective. The present thesis concerns the removal of 62 different active pharmaceutical ingredients commonly detected in Swedish wastewater effluents by means of chemical oxidation techniques. Techniques wit...

  14. Fouling of enhanced biological phosphorus removal-membrane bioreactors by humic-like substances.

    Science.gov (United States)

    Poorasgari, Eskandar; König, Katja; Fojan, Peter; Keiding, Kristian; Christensen, Morten Lykkegaard

    2014-12-01

    Fouling by free extracellular polymeric substances was studied in an enhanced biological phosphorus removal-membrane bioreactor. It was demonstrated that the free extracellular polymeric substances, primarily consisting of humic-like substances, were adsorbed to the membrane used in the enhanced biological phosphorus removal-membrane bioreactor plant. Infrared analyses indicated the presence of the humic-like substances on the membrane's active surface after filtration of the free extracellular polymeric substances suspension. Scanning electron microscopy showed the presence of a gel layer on the membrane surface after filtration of the free extracellular polymeric substances suspension. The gel layer caused a significant decline in water flux. This layer was not entirely removed by a backwashing, and the membrane's water flux could not be re-established. The membrane used in the enhanced biological phosphorus removal-membrane bioreactor plant showed infrared spectra similar to that fouled by the free extracellular polymeric substances suspension in the laboratory. Thus, the results of this study show the importance of humic-like substances in irreversible fouling of enhanced biological phosphorus removal-membrane bioreactor systems. PMID:25014564

  15. [Review on the main microorganisms and their metabolic mechanisms in enhanced biological phosphorus removal (EBPR) systems].

    Science.gov (United States)

    Sun, Xue; Zhu, Wei-Jing; Wang, Liang; Wu, Wei-Xiang

    2014-03-01

    Enhanced biological phosphorus removal (EBPR) process is applied widely for removing phosphorus from wastewater. Studies on functional microorganisms and their metabolic mechanisms are fundamental to effective regulation for stable operation and performance improvement of EBPR process. Two main types of microorganisms in EBPR systems, polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) were selected to summarize their metabolic mechanisms such as substrate uptake mechanisms, glycogen degradation pathways, extent of TCA cycle involvement and metabolic similarity between PAOs and GAOs. Application of molecular biology techniques in microbiology and metabolic mechanisms involved in the EBPR system was evaluated. Potential future research areas for the EBPR system and process optimization were also proposed. PMID:24984512

  16. Phosphate limitation in biological rapid sand filters used to remove ammonium from drinking water

    DEFF Research Database (Denmark)

    Lee, Carson Odell; Albrechtsen, Hans-Jørgen; Smets, Barth F.;

    2013-01-01

    Removing ammonium from drinking water is important for maintaining biological stability in distribution systems. This is especially important in regions that do not use disinfectants in the treatment process or keep a disinfectant residual in the distribution system. Problems with nitrification c...... the total number of ammonium oxidizing bacteria in the column. © 2013 American Water Works Association AWWA WQTC Conference Proceedings All Rights Reserved.......Removing ammonium from drinking water is important for maintaining biological stability in distribution systems. This is especially important in regions that do not use disinfectants in the treatment process or keep a disinfectant residual in the distribution system. Problems with nitrification can...

  17. Innovative low cost procedure for nutrient removal as an integrated element of a decentralised water management concept for rural areas.

    Science.gov (United States)

    Burde, M; Rolf, F; Grabowski, F

    2001-01-01

    The absence of large rivers with rather high niveau of self purifying effect in parts of east Germany leads to a discharging of the effluent of wastewater treatment plants into the groundwater in many cases. One useful consequence is the idea of realisation of decentralised measures and concepts in urban water resources management concerning municipal wastewater as well as rainfall, precipitation. At the same time, only the upper soil zone--a few decimetres--is water--saturated and thus discharge effective, even when extreme rainfall takes place. Underneath, however, there generally exists an unsaturated soil zone, which is up to now a rather unexplored retardation element of the hydrologic- and substrate-cycle. Nutrient removal in small wastewater treatment plants that are emptying into ground waters is often beneficial. The presented studies optimised an inexpensive method of subsequent enhanced wastewater treatment. The developed reactor is similar to a concentrated subsoil passage. The fixed bed reactor is divided in two sections to achieve aerobic and anoxic conditions for nitrification/denitrification processes. To enhance phosphorus removal, ferrous particles are put into the aerobic zone. Two series of column tests were carried out and a technical pilot plant was built to verify the efficiency of the process. The results show that this method can be implemented successfully.

  18. Effects of Solid Retention Time (SRT) on Sludge Characteristics in Enhanced Biological Phosphorus Removal (EBPR) Reactor

    OpenAIRE

    Li, N.; X Wang; N Ren; Zhang, K.; Kang, H; You, S.

    2008-01-01

    This study investigated the effects of solid retention time (SRT) on sludge characteristics and operational performance in enhanced biological phosphorus removal (EBPR) reactor. The results showed that the reactor operated at SRT of τ = 8.3 d could achieve phosphate removal efficiency η > 90 % and SVI < 100 mL g–1. In comparison, increasing SRT to τ = 16.6 d led to a decrease of phosphate removal (η < 85 %) and an increase of SVI value (160 mL g–1), implying a performance degradation and wors...

  19. Improving BOD removal at SNJ wastewater treatment plant by biological treatment

    OpenAIRE

    Hantanirina, Jeannine Marie Olga

    2010-01-01

    SNJ uses chemical precipitation method to treat domestic wastewater. With regard to organic removal requirement; chemical treatment alone does not seem to be sufficient at SNJ/IVAR wastewater plant. This thesis is to assess the performance of the aerobic biological treatment on the wastewater of the plant in order to upgrade the existing plant to include biological treatment. The work was to conduct a laboratory scale SBR test for determination of the wastewater characteristics and the effect...

  20. A strategy for xenobiotic removal using photocatalytic treatment, microbial degradation or integrated photocatalytic-biological process

    OpenAIRE

    Lapertot, Miléna; Pulgarin, César

    2007-01-01

    According to the limited natural resources and due to the risks of anthropogenic pollution, it appears necessary to react efficiently in order to remove existing contaminations and avoid the creation of new ones. Therefore, the purpose of this thesis is to propose a sustainable strategy for treating problematic pollutants with the most adequate process. First, an overview of the different treatment processes has been given. In particular, biological, photocatalytic and integrated biological-p...

  1. Combination of ion exchange system and biological reactors for simultaneous removal of ammonia and organics.

    Science.gov (United States)

    Park, Wooshin; Jang, Eunhee; Lee, Myun-Joo; Yu, Seungho; Kim, Tak-Hyun

    2011-04-01

    A novel process for a simultaneous removal of ammonia and organics was developed on the basis of ion exchange and biological reactions. From batch experiments, it was found out that NH(4)(+) could be removed effectively by combining cation exchange and biological nitrification showing 0.98 mg N/m(2) ∙ s of a maximum flux. On the other hand, the removal of NO(3)(-) was 3.5 times faster than NH(4)(+) and the maximum flux was calculated to be 3.4 mg N/m(2) ∙ s. The systems for NH(4)(+) and NO(3)(-) removal were combined for establishing the IEBR process. When the process was operated in a continuous mode, approximately 95.8% of NH(4)(+) was removed showing an average flux of 0.22 mg N/m(2) · s. The removal efficiency of total nitrogen was calculated as 94.5% whereas that of organics was 99.5%. It was concluded that the IEBR process would be effectively used for a simultaneous removal of NH(4)(+) and organics.

  2. Tracing the limits of organic micropollutant removal in biological wastewater treatment.

    Science.gov (United States)

    Falås, Per; Wick, Arne; Castronovo, Sandro; Habermacher, Jonathan; Ternes, Thomas A; Joss, Adriano

    2016-05-15

    Removal of organic micropollutants was investigated in 15 diverse biological reactors through short and long-term experiments. Short-term batch experiments were performed with activated sludge from three parallel sequencing batch reactors (25, 40, and 80 d solid retention time, SRT) fed with synthetic wastewater without micropollutants for one year. Despite the minimal micropollutant exposure, the synthetic wastewater sludges were able to degrade several micropollutants present in municipal wastewater. The degradation occurred immediately after spiking (1-5 μg/L), showed no strong or systematic correlation to the sludge age, and proceeded at rates comparable to those of municipal wastewater sludges. Thus, the results from the batch experiments indicate that degradation of organic micropollutants in biological wastewater treatment is quite insensitive to SRT increases from 25 to 80 days, and not necessarily induced by exposure to micropollutants. Long-term experiments with municipal wastewater were performed to assess the potential for extended biological micropollutant removal under different redox conditions and substrate concentrations (carbon and nitrogen). A total of 31 organic micropollutants were monitored through influent-effluent sampling of twelve municipal wastewater reactors. In accordance with the results from the sludges grown on synthetic wastewater, several compounds such as bezafibrate, atenolol and acyclovir were significantly removed in the activated sludge processes fed with municipal wastewater. Complementary removal of two compounds, diuron and diclofenac, was achieved in an oxic biofilm treatment. A few aerobically persistent micropollutants such as venlafaxine, diatrizoate and tramadol were removed under anaerobic conditions, but a large number of micropollutants persisted in all biological treatments. Collectively, these results indicate that certain improvements in biological micropollutant removal can be achieved by combining different

  3. A hypothesis on Microthrix parvicella proliferation in biological nutrient removal activated sludge systems with selector tanks.

    Science.gov (United States)

    Noutsopoulos, Constantinos; Mamais, Daniel; Andreadakis, Andreas; Stams, Alfons

    2012-05-01

    The objective of this study was to evaluate the ability of Microthrix parvicella for long-chain fatty acids uptake under anaerobic, anoxic, and aerobic conditions as well as its ability to utilize volatile fatty acids and long-chain fatty acids under anoxic and aerobic conditions. According to the results, a hypothesis on the competition between floc-forming microorganisms and M. parvicella for long-chain fatty acids uptake under aerobic, anoxic, and anaerobic conditions was formulated. According to this hypothesis, M. parvicella exhibits similar long-chain fatty acids uptake capacity with floc-forming microorganisms even at relatively high floc loading values that are very often imposed at selector tanks. Following this hypothesis, the failure of selector tanks to provide for an effective M. parvicella control is evidenced. Based on the experimental results, the ability of M. parvicella to utilize long-chain fatty acids with rates comparable to those of floc formers, even in anoxic conditions, in conjunction with its lower acetate utilization rates, provides a good explanation regarding its preference to slowly biodegradable organic carbon compounds.

  4. Extremely acidic mine lake ecosystems in Lusatia (Germany) : characterisation and development of sustainable, biology-based acidity removal technologies

    Energy Technology Data Exchange (ETDEWEB)

    Fyson, A. [Brandenburg Univ. of Technology, Cottbus, (Germany)]|[Inst. of Freshwater Ecology and Inland Fisheries, Berlin (Germany); Deneke, R.; Nixdorf, B. [Brandenburg Univ. of Technology, Cottbus, (Germany); Steinberg, C.E.W. [Inst. of Freshwater Ecology and Inland Fisheries, Berlin (Germany)

    2003-07-01

    There are approximately 500 infilled open-cast lignite pits in Germany that are extremely acidic because of high concentrations of dissolved metals, mostly iron and aluminium. The mining lakes have pH values of 2.4 to 3.4 and also have high sulphate concentrations. Efforts are being made to neutralize the lakes for recreational purposes. The acidity can be removed from the lakes in an economical and environmentally sustainable manner by flooding through diversion of neutral, nutrient-rich river water. This paper described the living conditions of the acidic mining lakes in the Lausitz region of Germany and summarized the benefits of the controlled eutrophication approach to enhance natural, self-sustaining processes for acid neutralization. Compared to infilling with river water, eutrophication increases lake productivity and removes acidity through sediment bound and water column biologically-mediated processes. The study involved basic research on particle transport in streams and lakes, pelagic food web interactions and submerged macrophyte metabolism. It also looked at the role of wetlands, bacterial interactions at the water-sediment interface, and modelling. It was shown that the addition of phosphorus and carbon to the water column can enhance primary production. Future studies will examine environmentally acceptable treatment strategies that offer an alternative to chemical treatment. 20 refs., 1 tab., 2 figs.

  5. Extremely acidic mine lake ecosystems in Lusatia (Germany) : characterisation and development of sustainable, biology-based acidity removal technologies

    International Nuclear Information System (INIS)

    There are approximately 500 infilled open-cast lignite pits in Germany that are extremely acidic because of high concentrations of dissolved metals, mostly iron and aluminium. The mining lakes have pH values of 2.4 to 3.4 and also have high sulphate concentrations. Efforts are being made to neutralize the lakes for recreational purposes. The acidity can be removed from the lakes in an economical and environmentally sustainable manner by flooding through diversion of neutral, nutrient-rich river water. This paper described the living conditions of the acidic mining lakes in the Lausitz region of Germany and summarized the benefits of the controlled eutrophication approach to enhance natural, self-sustaining processes for acid neutralization. Compared to infilling with river water, eutrophication increases lake productivity and removes acidity through sediment bound and water column biologically-mediated processes. The study involved basic research on particle transport in streams and lakes, pelagic food web interactions and submerged macrophyte metabolism. It also looked at the role of wetlands, bacterial interactions at the water-sediment interface, and modelling. It was shown that the addition of phosphorus and carbon to the water column can enhance primary production. Future studies will examine environmentally acceptable treatment strategies that offer an alternative to chemical treatment. 20 refs., 1 tab., 2 figs

  6. Oestrogen removal from biological pre-treated wastewater within decentralised sanitation and re-use concepts

    NARCIS (Netherlands)

    Mes, de T.Z.D.; Urmenyi, A.M.; Poot, A.A.; Wessling, M.; Mulder, M.H.V.; Zeeman, G.

    2006-01-01

    Two parallel researches were performed; one focused on the fate of oestrogens in the biological treatment systems within decentralised sanitation and re-use concepts (DESAR), the second related to the development of a suitable specific removal method. A new affinity membrane was developed using anti

  7. Biological Ammonia Removal: From Theory to Case Studies in 20 Minutes

    Science.gov (United States)

    This presentation documents the results of two pilot-scale treatment studies, in Ohio and Iowa, that investigated the biological removal of ammonia from ground water. Influent ammonia concentrations in the Ohio and Iowa studies averaged 1.3 and 3.3 mg/L - N, respectively. Both ...

  8. Recent developments in the biochemistry and ecology of enhanced biological phosphorus removal

    NARCIS (Netherlands)

    Kortstee, GJJ; Appeldoorn, KJ; Bonting, CFC; van Niel, EWJ; van Veen, HW

    2000-01-01

    Most of the genes encoding the enzymes involved in polyP synthesis and degradation and in phosphate transport have been studied in various Gram-negative bacteria. Progress has also been made in studying the biochemical mechanisms underlying the process of enhanced biological phosphorus removal (EBPR

  9. Microbial community changes in biological phosphate-removal systems on altering sludge phosphorus content

    NARCIS (Netherlands)

    Liu, WT; Linning, KD; Nakamura, K; Mino, T; Matsuo, T; Forney, LJ

    2000-01-01

    Biomarkers (respiratory quinones and cellular fatty acids) and denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA genes were used to characterize the microbial community structure of lab-scale enhanced biological phosphate-removal (EBPR) systems in response to altering sludge p

  10. Enhanced Biological Phosphorus Removal with Pseudomonas putida GM6 from Activated Sludge

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The enhanced biological phosphorus removal (EBPR) method is widely adopted for phosphorus removal from wastewater, yet little is known about its microbiological and molecular mechanisms. Therefore, it is difficult to predict and control the deterioration of the EBPR process in a large-scale municipal sewage treatment plant. This study used a novel strain isolated in the laboratory, Pseudomonas putida GM6, which had a high phosphate accumulating ability and could recover rapidly from the deteriorated system and enhance the capability of phosphorus removal in activated sludge. Strain GM6 marked with gfp gene, which was called GMTR, was delivered into a bench-scale sequencing batch reactor (SBR)of low efficiency, to investigate the colonization of GMTR and removal of phosphorus. After 21 days, the proportion of GMTR in the total bacteria of the sludge reached 9.2%, whereas the phosphorus removal rate was 96%, with an effluent concentration of about 0.2 mg L-1. In the reactor with the addition of GMTR, phosphorus was removed quickly, in 1 h under anaerobic conditions, and in 2 h under aerobic conditions. These evidences were characteristic of EBPR processes.Field testing was conducted at a hospital sewage treatment facility with low phosphorus removal capability. Twentyone days after Pseudononas putida GM6 was added, effluent phosphorus concentration remained around 0.3 mg L-1,corresponding to a removal rate of 96.8%. It was therefore demonstrated that Pseudomonas putida GM6 could be used for a quick startup and enhancement of wastewater biological phosphorus removal, which provided a scientific basis for potential large-scale engineering application.

  11. Identification of a novel group of bacteria in sludge from a deteriorated biological phosphorus removal reactor

    DEFF Research Database (Denmark)

    Nielsen, Alex Toftgaard; Liu, Wen-Tso; Filipe, Carlos;

    1999-01-01

    The microbial diversity of a deteriorated biological phosphorus removal reactor was investigated by methods not requiring direct cultivation. The reactor was fed with media containing acetate and high levels of phosphate (P/C weight ratio, 8:100) but failed to completely remove phosphate...... in the effluent and showed very limited biological phosphorus removal activity. Denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA was used to investigate the bacterial diversity. Up to 11 DGGE bands representing at least 11 different sequence types were observed; DNA from the 6...... obtained by the PCR-based DGGE method. Further, based on electron microscopy and standard staining microscopic analysis, this novel group was able to accumulate granule inclusions, possibly consisting of polyhydroxyalkanoate, inside the cells....

  12. Removal of disinfection by-products formation potential by biologically intensified process

    Institute of Scientific and Technical Information of China (English)

    AN Dong; LI Wei-guang; CUI Fu-yi; HE Xin; ZHANG Jin-song

    2005-01-01

    The removal of disinfection by-products formation potential(DBPFP) in artificially intensified biological activated carbon(IBAC) process which is developed on the basis of traditional ozone granular activated carbon was evaluated. By IBAC removals of 31% and 68% for THMFP and HAAFP were obtained respectively. Under identical conditions, the removals of the same substances were 4% and 32% respectively only by the granular activated carbon(GAC) process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. A clear linear correlation ( R2 = 0.9562 and R2 = 0.9007) between DOC HAAFP removal rate and Empty Bed Contact Time(EBCT) of IBAC process was observed, while that between THMFP removal rate and EBCT of GAC was R2 = 0.9782. In addition certain linear correlations between THMFP, HAAFP and UV254 ( R2 = 0.855 and R2 = 0.7702) were found for the treated water. For IBAC process there are also more advantages such as long backwashing cycle time, low backwashing intensity and prolonging activated carbon lifetime and so on.

  13. Removing undesirable color and boosting biological activity in red beet extracts using gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Sik; Lee, Eun Mi; Hong, Sung Hyun; Bai, Hyoung Woo; Chung, Byung Yeoup [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, In Chul [Youngdong University, Youngdong (Korea, Republic of)

    2011-10-15

    Red beet (Beta vulgaris L.) is a traditional and popular vegetable distributed in many part of the world and has been used as a natural colorant in many dairy products, beverages, candies and cattle products. Red beet roots contain two groups of betalain pigments, redviolet betacyanins and yellow betaxanthins. Betalains possess several biological activities such as antioxidant, anti-inflammatory, hepatoprotective, and anticancer properities. Recent trend of using natural products in industries tends toward multifunctional, high quality, and highpriced value foods and cosmetics. To meet the needs of consumers, cosmetics, medicine, and foods should contain the proper amount of natural products. Although the color removal processes such as filtration and absorption by clay are still useful, these procedures are difficult, time-consuming and costly. To overcome this problem, the radiation technology has emerged as a new way. Radiation technology has been applied to the decomposition and decoloration of pigment and is an efficient technique for inactivating pathogens, removing undesirable color in biomaterial extracts and improving or maintaining biological activities. Gamma-irradiation and electron beamirradiation techniques in previous reports were applied in order to remove any undesirable color and to improve or maintain biological activities of various extracts such as green tea leaves, licorice root, and S. chinensis fruits. Latorre et al. reported that betacyanin concentration decreased with the irradiation dose and significantly, in 35%, after 2.0 kGy of gamma-ray, whereas betaxathin concentration increased (about 11%-ratio with respect to control) after 1 kGy but decreased (about 19%) after 2 kGy. However, they did not try to analysis for completed removal of red beet pigments. Therefore, it is necessary to find the optimum irradiation dose for entirely removing red pigments in red beet. The aim of this work was to address the effects of the color removal and

  14. Removing undesirable color and boosting biological activity in red beet extracts using gamma irradiation

    International Nuclear Information System (INIS)

    Red beet (Beta vulgaris L.) is a traditional and popular vegetable distributed in many part of the world and has been used as a natural colorant in many dairy products, beverages, candies and cattle products. Red beet roots contain two groups of betalain pigments, redviolet betacyanins and yellow betaxanthins. Betalains possess several biological activities such as antioxidant, anti-inflammatory, hepatoprotective, and anticancer properities. Recent trend of using natural products in industries tends toward multifunctional, high quality, and highpriced value foods and cosmetics. To meet the needs of consumers, cosmetics, medicine, and foods should contain the proper amount of natural products. Although the color removal processes such as filtration and absorption by clay are still useful, these procedures are difficult, time-consuming and costly. To overcome this problem, the radiation technology has emerged as a new way. Radiation technology has been applied to the decomposition and decoloration of pigment and is an efficient technique for inactivating pathogens, removing undesirable color in biomaterial extracts and improving or maintaining biological activities. Gamma-irradiation and electron beamirradiation techniques in previous reports were applied in order to remove any undesirable color and to improve or maintain biological activities of various extracts such as green tea leaves, licorice root, and S. chinensis fruits. Latorre et al. reported that betacyanin concentration decreased with the irradiation dose and significantly, in 35%, after 2.0 kGy of gamma-ray, whereas betaxathin concentration increased (about 11%-ratio with respect to control) after 1 kGy but decreased (about 19%) after 2 kGy. However, they did not try to analysis for completed removal of red beet pigments. Therefore, it is necessary to find the optimum irradiation dose for entirely removing red pigments in red beet. The aim of this work was to address the effects of the color removal and

  15. Removing Iron and Manganese Simultaneously from Ground Water Using One-stage Biological Filter

    Institute of Scientific and Technical Information of China (English)

    XUE Gang; GAO Pin; GONG Qing-jie

    2009-01-01

    A novel process for removing iron and manganese simultaneously in ground water, which consisted of simple aeration and one-stage filtration, was developed in this research. It was found that the biological process had much higher manganese removal efficiency than chemical contact oxidation process. At the same time, the optimal operation parameters of aeration and biological filtration such as DO concentration and pH after aeration, filtration rate before and after startup, filtration operation cycle and backwashing rate, etc., were also obtained by experiments. By analyzing water quafity in different positions of filter bed, it was found that the oxidation of Fe2+ in biological filter bed adapted to first-order reaction, whereas the oxidation of Mn2+ conformed to zero-order reaction, which could be explained by Michaelis-Menten enzyme reaction equation when substrate concentration was far more than bacteria amount.

  16. Characteristics and transformations of dissolved organic nitrogen in municipal biological nitrogen removal wastewater treatment plants

    Science.gov (United States)

    Huo, Shouliang; Xi, Beidou; Yu, Honglei; Qin, Yanwen; Zan, Fengyu; Zhang, Jingtian

    2013-12-01

    Dissolved organic nitrogen (DON) represents most of the dissolved nitrogen in the effluent of biological nitrogen removal (BNR) wastewater treatment plants (WWTPs). The characteristics of wastewater-derived DON in two different WWTPs were investigated by several different methods. The major removals of DON and biodegradable dissolved organic nitrogen (BDON) along the treatment train were observed in the anaerobic process. Dissolved combined amino acids (DCAA) and dissolved free amino acids (DFAA) in the effluent accounted approximately for less than 4% and 1% of the effluent DON, respectively. Approximately half of wastewater-derived DON was capable of passing through a 1 kDa ultrafilter, and low MW DON cannot effectively be removed by BNR processes. More than 80% of effluent DON was composed of hydrophilic compounds, which stimulate algal growth. The study provided important information for future upgrading of WWTPs or the selection of DON removal systems to meet more demanding nitrogen discharge limits.

  17. Seasonal and interannual variability of physical and biological dynamics at the shelfbreak front of the Middle Atlantic Bight: nutrient supply mechanisms

    Directory of Open Access Journals (Sweden)

    R. He

    2011-10-01

    Full Text Available A high-resolution, 3-dimensional coupled biophysical model is used to simulate ocean circulation and ecosystem variations at the shelfbreak front of the Middle Atlantic Bight (MAB. Favorable comparisons between satellite observations and model hindcast solutions from January 2004 to November 2007 indicate the model has intrinsic skills in resolving fundamental physical and biological dynamics at the MAB shelfbreak. Seasonal and interannual variability of ocean physical and biological states and their driving mechanisms are further analyzed. The domain-wide upper water column nutrient content is found to peak in late winter-early spring. Phytoplankton spring bloom starts 1–2 months later, followed by zooplankton bloom in early summer. Our analysis shows the variability of shelfbreak nutrient supply is controlled by local mixing that deepens the mixed layer and injects deep ocean nutrients into the upper water column and alongshore nutrient transport by the shelfbreak jet and associated currents. Nutrient vertical advection associated with the shelfbreak bottom boundary layer convergence is another significant contributor. Spring mean nutrient budget diagnostics along the Nantucket transect are compared between nutrient rich 2004 and nutrient poor 2007. Physical advection and diffusion play the major role in determining strong interannual variations in shelfbreak nutrient content. The biological (source minus sink term is very similar between these two years.

  18. Nitrogen Eutrophication on the Colorado Plateau: Using Biological Indicators to Detect Nutrient Enrichment in the Grand Canyon Region

    Science.gov (United States)

    Kenkel, J. A.; Johnson, N.; Hultine, K. R.; Sesnie, S.; Sisk, T.

    2012-12-01

    Human activities have more than doubled the availability of biologically reactive forms of nitrogen (N) since the industrial and agricultural revolutions. Though N is an important plant nutrient, increased deposition initiates a cascade of deleterious effects including ecosystem acidification, biodiversity loss, and increased smog and haze. Atmospheric pollution continues to threaten the air quality of the 16 Class 1 Wilderness areas on the Colorado Plateau, including Grand Canyon National Park (GCNP). However, the ecological impacts of N deposition in these historically N-limited, nutrient sensitive arid regions, are little- known. Here, we report baseline atmospheric and terrestrial responses to anthropogenic N deposition derived from vehicular exhaust in GCNP and long-range deposition from a local coal-fired power plant, the Navajo Generating Station (NGS). We used passive air samplers, natural abundance δ15N stable isotope analysis, and nutrient analysis to observe N patterns in air, soils, and pinyon pine (Pinus edulis) foliage. In GCNP, samples were collected from ten sites over an eight-month period in areas of projected low to high vehicular N deposition (i.e. distance from primary roadways). On the Paria Plateau, northeast of GCNP and in close proximity to the NGS, samples were collected along a distance gradient from the NGS, across the Plateau. In both study areas, atmospheric deposition, as well as soil and pine- needle nutrient concentrations show significant negative relationships with increased distance from N-source (pbiodiversity and air quality standards for the southwestern U.S.

  19. The Microbial Database for Danish wastewater treatment plants with nutrient removal (MiDas-DK) – a tool for understanding activated sludge population dynamics and community stability

    DEFF Research Database (Denmark)

    Mielczarek, Artur Tomasz; Saunders, Aaron Marc; Larsen, Poul;

    2013-01-01

    , analyzed and associated with extensive operational data from the plants. The community composition was analyzed by quantitative fluorescence in situ hybridization (FISH) supported by 16S rRNA amplicon sequencing and deep metagenomics. MiDas-DK has been a powerful tool to study the complex activated sludge......Since 2006 more than 50 Danish full-scale wastewater treatment plants with nutrient removal have been investigated in a project called ‘The Microbial Database for Danish Activated Sludge Wastewater Treatment Plants with Nutrient Removal (MiDas-DK)’. Comprehensive sets of samples have been collected...... ecosystems, and, besides many scientific articles on fundamental issues on mixed communities encompassing nitrifiers, denitrifiers, bacteria involved in P-removal, hydrolysis, fermentation, and foaming, the project has provided results that can be used to optimize the operation of full-scale plants and carry...

  20. Biological Removal of Phosphate Using Phosphate Solubilizing Bacterial Consortium from Synthetic Wastewater: A Laboratory Scale

    Directory of Open Access Journals (Sweden)

    Dipak Paul

    2015-01-01

    Full Text Available Biological phosphate removal is an important process having gained worldwide attention and widely used for removing phosphorus from wastewater. The present investigation was aimed to screen the efficient phosphate solubilizing bacterial isolates and used to remove phosphate from synthetic wastewater under shaking flasks conditions. Pseudomonas sp. JPSB12, Enterobacter sp. TPSB20, Flavobacterium sp. TPSB23 and mixed bacterial consortium (Pseudomonas sp. JPSB12+Enterobacter sp. TPSB20+Flavobacterium sp. TPSB23 were used for the removal of phosphate. Among the individual strains, Enterobacter sp. TPSB20 was removed maximum phosphate (61.75% from synthetic wastewater in presence of glucose as a carbon source. The consortium was effectively removed phosphate (74.15-82.50% in the synthetic wastewater when compared to individual strains. The pH changes in culture medium with time and extracellular phosphatase activity (acid and alkaline were also investigated. The efficient removal of phosphate by the consortium may be due to the synergistic activity among the individual strains and phosphatase enzyme activity. The use of bacterial consortium in the remediation of phosphate contaminated aquatic environments has been discussed.

  1. Biological groundwater treatment for chromium removal at low hexavalent chromium concentrations.

    Science.gov (United States)

    Mamais, Daniel; Noutsopoulos, Constantinos; Kavallari, Ioanna; Nyktari, Eleni; Kaldis, Apostolos; Panousi, Eleni; Nikitopoulos, George; Antoniou, Kornilia; Nasioka, Maria

    2016-06-01

    The objective of this work is to develop and evaluate biological groundwater treatment systems that will achieve hexavalent chromium reduction and total chromium removal from groundwater at hexavalent chromium (Cr(VI)) groundwater concentrations in the 0-200 μg/L range. Three lab-scale units operated, as sequencing batch reactors (SBR) under aerobic, anaerobic and anaerobic-aerobic conditions. All systems received groundwater with a Cr(VI) content of 200 μg/L. In order to support biological growth, groundwater was supplemented with milk, liquid cheese whey or a mixture of sugar and milk to achieve a COD concentration of 200 mg/L. The results demonstrate that a fully anaerobic system or an anaerobic-aerobic system dosed with simple or complex external organic carbon sources can lead to practically complete Cr(VI) reduction to Cr(III). The temperature dependency of maximum Cr(VI) removal rates can be described by the Arrhenius relationship. Total chromium removal in the biological treatment systems was not complete because a significant portion of Cr(III) remained in solution. An integrated system comprising of an anaerobic SBR followed by a sand filter achieved more than 95% total chromium removal thus resulting in average effluent total and dissolved chromium concentrations of 7 μg/L and 3 μg/L, respectively. PMID:26971177

  2. Removal of anaerobic soluble microbial products in a biological activated carbon reactor.

    Science.gov (United States)

    Dong, Xiaojing; Zhou, Weili; He, Shengbing

    2013-09-01

    The soluble microbial products (SMP) in the biological treatment effluent are generally of great amount and are poorly biodegradable. Focusing on the biodegradation of anaerobic SMP, the biological activated carbon (BAC) was introduced into the anaerobic system. The experiments were conducted in two identical lab-scale up-flow anaerobic sludge blanket (UASB) reactors. The high strength organics were degraded in the first UASB reactor (UASB1) and the second UASB (UASB2, i.e., BAC) functioned as a polishing step to remove SMP produced in UASB1. The results showed that 90% of the SMP could be removed before granular activated carbon was saturated. After the saturation, the SMP removal decreased to 60% on the average. Analysis of granular activated carbon adsorption revealed that the main role of SMP removal in BAC reactor was biodegradation. A strain of SMP-degrading bacteria, which was found highly similar to Klebsiella sp., was isolated, enriched and inoculated back to the BAC reactor. When the influent chemical oxygen demand (COD) was 10,000 mg/L and the organic loading rate achieved 10 kg COD/(m3 x day), the effluent from the BAC reactor could meet the discharge standard without further treatment. Anaerobic BAC reactor inoculated with the isolated Klebsiella was proved to be an effective, cheap and easy technical treatment approach for the removal of SMP in the treatment of easily-degradable wastewater with COD lower than 10,000 mg/L. PMID:24520716

  3. Combined advanced oxidation and biological treatment processes for the removal of pesticides from aqueous solutions

    International Nuclear Information System (INIS)

    Advanced oxidation processes were combined with biological treatment processes in this study to remove both pesticides and then the COD load from aqueous solutions. It was found that O3 and O3/UV oxidation systems were able to reach 90 and 100%, removal of the pesticide Deltamethrin, respectively, in a period of 210 min. The use of O3 combined with UV radiation enhances pesticides degradation and the residual pesticide reaches zero in the case of Deltamethrin. The combined O3/UV system can reduce COD up to 20% if the pH of the solution is above 4. Both pesticide degradation and COD removal in the combined O3/UV system follow the pseudo-first-order kinetics and the parameters of this model were evaluated. The application of the biological treatment to remove the bulk COD from different types of feed solution was investigated. More than 95% COD removal was achieved when treated wastewater by the O3/UV system was fed to the bioreactor. The parameters of the proposed Grau model were estimated

  4. Effect of continuous addition of an organic substrate to the anoxic phase on biological phosphorus removal

    DEFF Research Database (Denmark)

    Meinhold, Jens; Pedersen, Heinz; Arnold, Eva;

    1998-01-01

    The continuous introduction of a biological phosphorus removal (BPR) promoting organic substrate to the denitrifying reactor of a BPR process is examined through a series of batch experiments using acetate as model organic substrate. Several observations are made regarding the influence...... while a net P-release occurs. Whether the introduction of BPR promoting organic substrates to the denitrifying reactor is detrimental to overall P-removal appears to be dependent on the interaction between aerobic P-uptake, which is a function of PHB level, and the aerobic residence time. (C) 1998...

  5. “Candidatus Propionivibrio aalborgensis”: A Novel Glycogen Accumulating Organism Abundant in Full-Scale Enhanced Biological Phosphorus Removal Plants

    DEFF Research Database (Denmark)

    Albertsen, Mads; McIlroy, Simon Jon; Stokholm-Bjerregaard, Mikkel;

    2016-01-01

    Enhanced biological phosphorus removal (EBPR) is widely used to remove phosphorus from wastewater. The process relies on polyphosphate accumulating organisms (PAOs) that are able to take up phosphorus in excess of what is needed for growth, whereby phosphorus can be removed from the wastewater...

  6. Internal carbon source from sludge pretreated by microwave-H2O2 for nutrient removal in A2/O-membrane bioreactors.

    Science.gov (United States)

    Xu, Rongle; Zhang, Qing; Tong, Juan; Wei, Yuansong; Fan, Yaobo

    2015-01-01

    To improve the nutrient removal, the feasibility was studied for the organics released from sludge pretreated by microwave-H2O2 process (MHP) to be used as internal carbon source in two A2/O-membrane bioreactors (MBRs). The experiments were conducted for the nutrient removal and the membrane fouling. The results showed that the removal efficiencies of TN and TP were improved by 11% and 28.34%, respectively, as C/N ratio was adjusted to 8 by adding the internal carbon source, and the ratio of soluble chemical oxygen demand (sCOD) consumed easily for denitrification was about 46% of the total sCOD in the internal carbon source. The addition of the internal carbon sources did not lead to severe membrane fouling in the experimental A2/O-MBR. It is implied that the organics released from sludge pretreated by MHP could be used as the internal carbon source to enhance the nutrient removal in A2/O-MBRs.

  7. Simultaneous nitrification and denitrification in step feeding biological nitrogen removal process

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The simultaneous nitrification and denitrification in step-feeding biological nitrogen removal process were investigated under different influent substrate concentrations and aeration flow rates.Biological occurrence of simultaneous nitrification and denitrifieation was verified in the aspect of nitrogen mass balance and alkalinity.The experimental results also showed that there was a distinct linear relationship between simultaneous nitrification and denitrification and DO concentration under the conditions of low and high aeration flow rate.In each experimental run the floe sizes of activated sludge were also measured and the results showed that simultaneous nitrification and denitrification could occur with very small size of floc.

  8. Effect of side-stream phosphorus recovery on biological phosphorus removal performance investigated by chemical and microbial analyses in a novel BNR-IC process.

    Science.gov (United States)

    Zou, H M; Lu, X W; Li, T

    2014-01-01

    The aim of this study was to assess the effect of side-stream ratio (SSR) on performance of phosphorus (P) removal and recovery in a novel process linking biological nutrients removal (BNR) and induced crystallization (IC). Results showed that P removal efficiency was significantly enhanced when given an appropriate SSR, resulting in effluent P concentrations decreasing from 0.75 to 0.39 mg/L with an increase of SSR from 0 to 35%, where a maximum of 7.19 mg/L P recovery amount was obtained at 35% of SSR. Increasing the SSR can favor the P recovery, while an excessively high SSR (more than 35%) would have a negative effect on the subsequent biological P removal in the BNR-IC system. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis showed that in total, 11 DGGE bands of highest species richness were visually detected and significant changes in microbial community structure were found, with SSR variations ranging from 0 to 55%. Moreover, an increase in SSR can cause an increase in microbial community biodiversity; where microbial populations correspond to the 11 bands, they were generally classified into five different phyla or classes (Beta-, Gamma-, and Deltaproteobacteria, as well as Clostridia and Flavobacteria) based on the evolutionary tree analysis. PMID:25401306

  9. Effects of anaerobic reaction time and sludge age on the biological phosphorus removal in SBR

    International Nuclear Information System (INIS)

    In this research, a pilot consisting of two Sequencing Batch Reactors used to remove phosphorus biologically. Both reactors were in operation in a 12 hours cycle and they were controlled by a computer. The blank one had no primary anaerobic stage and its aeration time was 9.5 hours. The other one had the primary anaerobic stage with no change in the total reaction time (9.5 hours). The average concentration of influent phosphorus and COD in reactors were 7.5 and 800 milligram per litre respectively. In two months periods, the average efficiencies of ph osporus removal for the blank reactor and the second reactor with anaerobic reaction times of 2,3, and 4.5 hours were 16%, 26%, 64%, and 99% respectively. In the reactor with anaerobic reaction time of 4.5 hours, increasing the sludge age from 5 days to 10 days resulted in decreasing of phosphorus removal efficiency from 99% to 87%. In general, the result of this investigation show that the increases of anaerobic reaction time can increase the efficiency of phosphorus removal, because of the prevalence of phosphorus removing microorganisms over other species. Also, the accurate control of additional sludge volume (clogged age) has an appropriate effect on the removal efficiency

  10. Temperature influence on biological phosphorus removal induced by aerobic/extended-idle regime.

    Science.gov (United States)

    Chen, Hong-Bo; Wang, Dong-Bo; Li, Xiao-Ming; Yang, Qi; Luo, Kun; Zeng, Guang-Ming

    2014-05-01

    Previous researches have demonstrated that biological phosphorus removal (BPR) from wastewater could be driven by the aerobic/extended-idle (A/EI) regime. This study further investigated temperature effects on phosphorus removal performance in six A/EI sequencing batch reactors (SBRs) operated at temperatures ranging from 5 to 30 °C. The results showed that phosphorus removal efficiency increased with temperature increasing from 5 to 20 °C but slightly decreased when temperature continually increased to 30 °C. The highest phosphorus removal rate of 97.1 % was obtained at 20 °C. The biomass cultured at 20 °C contained more polyphosphate accumulating organisms (PAO) and less glycogen accumulating organisms (GAO) than that cultured at any other temperatures investigated. The mechanism studies revealed that temperature affected the transformations of glycogen and polyhydroxyalkanoates, and the activities of exopolyphosphatase and polyphosphate kinase activities. In addition, phosphorus removal performances of the A/EI and traditional anaerobic/oxic (A/O) SBRs were compared at 5 and 20 °C, respectively. The results showed the A/EI regime drove better phosphorus removal than the A/O regime at both 5 and 20 °C, and more PAO and less GAO abundances in the biomass might be the principal reason for the higher BPR in the A/EI SBRs as compared with the A/O SBRs. PMID:24464081

  11. Micropollutant removal during biological wastewater treatment and a subsequent ozonation step

    Energy Technology Data Exchange (ETDEWEB)

    Schaar, Heidemarie, E-mail: hschaar@iwag.tuwien.ac.a [Institute of Water Quality, Resources and Waste Management, Vienna University of Technology, Karlsplatz 13/226, 1040 Vienna (Austria); Clara, Manfred; Gans, Oliver [Umweltbundesamt, Spittelauer Lande 5, 1090 Vienna (Austria); Kreuzinger, Norbert [Institute of Water Quality, Resources and Waste Management, Vienna University of Technology, Karlsplatz 13/226, 1040 Vienna (Austria)

    2010-05-15

    The design criteria for wastewater treatment plants (WWTP) and the sludge retention time, respectively, have a significant impact on micropollutant removal. The upgrade of an Austrian municipal WWTP to nitrogen removal (best available technology, BAT) resulted in increased elimination of most of the analyzed micropollutants. Substances, such as bisphenol-A, 17alpha-ethinylestradiol and the antibiotics erythromycin and roxithromycin were only removed after the upgrade of the WWTP. Nevertheless, the BAT was not sufficient to completely eliminate these compounds. Thus, a pilot scale ozonation plant was installed for additional treatment of the effluent. The application of 0.6 g O{sub 3} g DOC{sup -1} increased the removal of most of the micropollutants, especially for compounds that were not degraded in the previous biological process, as for example carbamazepine and diclofenac. These results indicated that the ozonation of WWTP effluent is a promising technology to further decrease emissions of micropollutants from the treatment process. - SRT is an important criterion for micropollutant removal in wastewater treatment and the application of ozone is suitable for further removal of micropollutants.

  12. Preparation of ferric-activated sludge-based adsorbent from biological sludge for tetracycline removal.

    Science.gov (United States)

    Yang, Xin; Xu, Guoren; Yu, Huarong; Zhang, Zhao

    2016-07-01

    Ferric activation was novelly used to produce sludge-based adsorbent (SBA) from biological sludge through pyrolysis, and the adsorbents were applied to remove tetracycline from aqueous solution. The pyrolysis temperature and mass ratio (activator/dried sludge) greatly influenced the surface area and pore characteristics of SBA. Ferric activation could promote the porous structure development of adsorbents, and the optimum preparation conditions were pyrolysis temperature 750°C and mass ratio (activator/dried sludge) 0.5. In batch experiments, ferric-activated SBA showed a higher adsorption capacity for tetracycline than non-activated SBA, because the enhanced mesoporous structure favored the diffusion of tetracycline into the pores, the iron oxides and oxygen-containing functional groups in the adsorbents captured tetracycline by surface complexation. The results indicate that ferric activation is an effective approach for preparing adsorbents from biological sludge to remove tetracycline, providing a potential option for waste resource recovery. PMID:27038265

  13. A metabolic model for members of the genus Tetrasphaera involved in enhanced biological phosphorus removal

    OpenAIRE

    Kristiansen, Rikke; Nguyen, Hien Thi Thu; Saunders, Aaron Marc; Nielsen, Jeppe Lund; Wimmer, Reinhard; Le, Vang Quy; McIlroy, Simon Jon; Petrovski, Steve; Seviour, Robert J.; Calteau, Alexandra; Nielsen, Kåre Lehmann; Nielsen, Per Halkjær

    2012-01-01

    Members of the genus Tetrasphaera are considered to be putative polyphosphate accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) from wastewater. Although abundant in Danish full-scale wastewater EBPR plants, how similar their ecophysiology is to ‘Candidatus Accumulibacter phosphatis' is unclear, although they may occupy different ecological niches in EBPR communities. The genomes of four Tetrasphaera isolates (T. australiensis, T. japonica, T. elongata and T. jenk...

  14. Dynamics of Intracellular Polymers in Enhanced Biological Phosphorus Removal Processes under Different Organic Carbon Concentrations

    OpenAIRE

    Lizhen Xing; Li Ren; Bo Tang,; Guangxue Wu; Yuntao Guan

    2013-01-01

    Enhanced biological phosphorus removal (EBPR) may deteriorate or fail during low organic carbon loading periods. Polyphosphate accumulating organisms (PAOs) in EBPR were acclimated under both high and low organic carbon conditions, and then dynamics of polymers in typical cycles, anaerobic conditions with excess organic carbons, and endogenous respiration conditions were examined. After long-term acclimation, it was found that organic loading rates did not affect the yield of PAOs and the app...

  15. Characteristics and conditioning of anaerobically digested sludge from a biological phosphorus removal plant

    OpenAIRE

    Nash, Jeffrey William

    1989-01-01

    A study of the anaerobically digested sludge form a full-scale biological phosphorus removal (BPR) plant (York River Wastewater Treatment Plant, York River, Va.) was conducted to determine the effects of BPR on sludge characteristics and conditioning requirements. Data collected from the plant indicated that both the total and soluble phosphorus (P) concentrations in the anaerobically digested sludge increased dramatically with the initiation of BPR. Accompanying this ...

  16. Improving settleability and achieving biological phosphorus removal through the application of sidestream gravimetric selectors

    OpenAIRE

    Welling, Claire Marie

    2015-01-01

    This project utilizes hydrocyclones in wastewater treatment to select for heavier solids, and has been used before in multiple small-scale systems. This is the first implementation of hydrocyclones in a full-scale plant for the purpose of increased settleability, while also achieving enhanced biological phosphorus removal without the use of an anaerobic selector. Hydrocyclones receive mixed liquor tangentially and separate light solids from more dense solids through their tapered shape, in...

  17. Advances in investigation of new technologies on biological nitrogen removal of waste water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y.; Zhang, J.; Xu, A.; Li, R. [CUMT, Xuzhou (China). School of Environment and Spatial Information

    2004-03-15

    The progresses of biological nitrogen removal from waste water, such as the investigation on shortcut nitrification denitrification, simultaneous nitrification denitrification (SND). Toxic ammonium oxidation (ANAMMOX) and ecology superior nitrification denitrification (ECOSUNIDES) were analyzed and discussed. The advantages of the new technology was compared with the traditional ones. It can be concluded that the new technology is promising for further investigations and applications. 9 refs., 2 figs.

  18. BIOLOGICAL AERATED FILTERS (BAFs FOR CARBON AND NITROGEN REMOVAL: A REVIEW

    Directory of Open Access Journals (Sweden)

    ELSHAFIE AHMED

    2012-08-01

    Full Text Available Biological aerated filters (BAFs are an emerging wastewater treatment technology designed for a wide range of municipal and industrial applications. This review paper presents and discusses of the influence C/N ratio, nitrification and denitrification principle, effect of pH, DO and alkalinity on the nitrification and denitrification systems, organic and hydraulic loading of BAF reactor, etc. Results from upflow and downflow biofilter pilot at different condition, with nitrification and denitrification are reviewed. Under the optimal conditions, significant amount of COD, ammonia-nitrogen and total nitrogen were removed. Removal rates based on reactor volume for different carbon-aceous COD and ammonia loading rate are reported. The BAF system for the nitrification and denitrification processes for carbon and nitrogen removal from the wastewater need to be evaluated and applied properly to protect of our environment and resources.

  19. A metagenome of a full-scale microbial community carrying out Enhanced Biological Phosphorus Removal

    DEFF Research Database (Denmark)

    Albertsen, Mads; Hansen, Lea Benedicte Skov; Saunders, Aaron Marc;

    2012-01-01

    Enhanced biological phosphorus removal (EBPR) is widely used for removal of phosphorus from wastewater. In this study, a metagenome (18.2 Gb) was generated using Illumina sequencing from a full-scale EBPR plant to study the community structure and genetic potential. Quantitative fluorescence...... the use of qFISH. The genetic potential for community function showed enrichment of genes involved in phosphate metabolism and biofilm formation, reflecting the selective pressure of the EBPR process. Most contigs in the assembled metagenome had low similarity to genes from currently sequenced genomes......, underlining the need for more reference genomes of key EBPR species. Only the genome of ‘Candidatus Accumulibacter’, a genus of phosphorus-removing organisms, was closely enough related to the species present in the metagenome to allow for detailed investigations. Accumulibacter accounted for only 4.8% of all...

  20. Enhancing combined biological nitrogen and phosphorus removal from wastewater by applying mechanically disintegrated excess sludge.

    Science.gov (United States)

    Zubrowska-Sudol, Monika; Walczak, Justyna

    2015-06-01

    The goal of the study was to evaluate the possibility of applying disintegrated excess sludge as a source of organic carbon to enhance biological nitrogen and phosphorus removal. The experiment, performed in a sequencing batch reactor, consisted of two two-month series, without and with applying mechanically disintegrated excess sludge, respectively. The effects on carbon, nitrogen and phosphorus removal were observed. It was shown that the method allows enhancement of combined nitrogen and phosphorus removal. After using disintegrated sludge, denitrification effectiveness increased from 49.2 ± 6.8% to 76.2 ± 2.3%, which resulted in a decline in the NOx-N concentration in the effluent from the SBR by an average of 21.4 mg NOx-N/L. Effectiveness of biological phosphorus removal increased from 28.1 ± 11.3% to 96.2 ± 2.5%, thus resulting in a drop in the [Formula: see text] concentration in the effluent by, on average, 6.05 mg PO4(3-)-P/L. The application of disintegrated sludge did not deteriorate effluent quality in terms of COD and NH4(+)-N. The concentration of NH4(+)-N in both series averaged 0.16 ± 0.11 mg NH4(+)-N/L, and the concentration of COD was 15.36 ± 3.54 mg O2/L. PMID:25776916

  1. Removal of micropollutants in WWTP effluent by biological assisted membrane carbon filtration (BioMAC).

    Science.gov (United States)

    Weemaes, M; Fink, G; Lachmund, C; Magdeburg, A; Stalter, D; Thoeye, C; De Gueldre, G; Van De Steene, B

    2011-01-01

    In the frame of the European FP6 project Neptune, a combination of biological activated carbon with ultrafiltration (BioMAC) was investigated for micropollutant, pathogen and ecotoxicity removal. One pilot scale set-up and two lab-scale set-ups, of which in one set-up the granular activated carbon (GAC) was replaced by sand, were followed up during a period of 11 months. It was found that a combination of GAC and ultrafiltration led to an almost complete removal of antibiotics and a high removal (>80%) of most of the investigated acidic pharmaceuticals and iodinated contrast media. The duration of the tests did however not allow to conclude that the biological activation was able to extend the lifetime of the GAC. Furthermore, a significant decrease in estrogenic and anti-androgenic activity could be illustrated. The set-up in which GAC was replaced by sand showed a considerably lower removal efficiency for micropollutants, especially for antibiotics but no influence on steroid activity. PMID:21245556

  2. Biological sulfate removal from construction and demolition debris leachate: Effect of bioreactor configuration

    International Nuclear Information System (INIS)

    Highlights: • Novel biological technique for gypsum removal from CDD. • CDDS leachate treatment performed using different sulfate reducing bioreactors. • Gypsum in CDD can be used as a source of sulfate for sulfate reducing bacteria. • High calcium concentration (1000 mg L−1) did not affect the bioreactor performance. - Abstract: Due to the contamination of construction and demolition debris (CDD) by gypsum drywall, especially, its sand fraction (CDD sand, CDDS), the sulfate content in CDDS exceeds the posed limit of the maximum amount of sulfate present in building sand (1.73 g sulfate per kg of sand for the Netherlands). Therefore, the CDDS cannot be reused for construction. The CDDS has to be washed in order to remove most of the impurities and to obtain the right sulfate content, thus generating a leachate, containing high sulfate and calcium concentrations. This study aimed at developing a biological sulfate reduction system for CDDS leachate treatment and compared three different reactor configurations for the sulfate reduction step: the upflow anaerobic sludge blanket (UASB) reactor, inverse fluidized bed (IFB) reactor and gas lift anaerobic membrane bioreactor (GL-AnMBR). This investigation demonstrated that all three systems can be applied for the treatment of CDDS leachate. The highest sulfate removal efficiency of 75–85% was achieved at a hydraulic retention time (HRT) of 15.5 h. A high calcium concentration up to 1000 mg L−1 did not give any adverse effect on the sulfate removal efficiency of the IFB and GL-AnMBR systems

  3. Comparison Between Biological Treatment and Chemical Precipitation for Nitrogen Removal from Old Landfill Leachate

    Directory of Open Access Journals (Sweden)

    Long Tengrui

    2007-01-01

    Full Text Available The study reports the results of a laboratory scale investigation aimed at evaluating the effectiveness of mature municipal landfill leachate treatment by a biological stage (used SBBR as a biological treatment and Chemical precipitation (Used MAP precipitation (magnesium ammonium phosphate to study the nitrogen removal capabilities for treatment of sanitary landfill leachate containing high ammonia concentration, and the comparison between them. The monitored sample taken from the Chang Sheng bridge landfill site in Chongqing city-China, has its concentrations of COD, BOD5, and NH3-N about 1650, 75 and 1100 mg/l respectively. The results from SBBR showed that after two months long period of domestication and one month period of stability, the ammonia nitrogen removal efficiency reached to 99% in the SBBR reactor, at nitrogen loading rate 0.51 kg TN/m3 per day and HRT was 9 hours, met to Chinese standards for discharge. The results of the MAP precipitation was technically effective to remove the high NH3-N strength of over 1100 mg/l from the raw leachate at molar ratio of Mg2+: NH4+: PO4-3 of 1:1:1, they demonstrated a very satisfactory removal of ammonia; an initial NH3+-N concentration of 1100 mg/l contained in the raw leachate was quickly reduced to 28 mg/l within 15 min, while the pH producing a maximum removal of ammonia was 9.0. The percent removal of ammonia after treatment by MAP was 97.5%.

  4. The Denitrifying Biological Phosphorus Removal Performance in Anaerobic/Anoxic Sequencing Batch Reactor: The Effect of Carbon Source

    OpenAIRE

    Gürtekin, Engin; Nusret ŞEKERDAĞ

    2015-01-01

    In this study, the effect of carbon source on denitrifying biological phosphorus removal performance in acetate and glucose fed two anaerobic/anoxic sequencinq batch reactor (SBR) was investigated. Glucose and acetate were used as the substrates. In acetate and glucose fed reactors, the COD (Chemical Oxygen Demand) removal efficiencies were 91,90% and PO4-P removal efficiencies were 87,51% respectively. These results shows that the phosphorus removal efficiency is lower in glucose fed reactor.

  5. Chemical, Physical, and Biological Factors Influencing Nutrient Availability and Plant Growth in a Pine Tree Substrate

    OpenAIRE

    Jackson, Brian Eugene

    2008-01-01

    Pine tree substrate (PTS) produced from freshly harvested loblolly pine (Pinus taeda L.) trees has potential for replacing or reducing the use of aged pine bark (PB) and peat moss as container substrates for horticulture crop production. The objective of this work was to determine the factors influencing nutrient availability in PTS compared to PB or peat substrates. Chapter two reports data on the response of japanese holly and azalea to fertilizer rate when grown in PTS and PB. This stud...

  6. Environmental assessment of nutrient recycling from biological pig slurry treatment--impact of fertilizer substitution and field emissions.

    Science.gov (United States)

    Brockmann, Doris; Hanhoun, Mary; Négri, Ophélie; Hélias, Arnaud

    2014-07-01

    Pig slurry treatment is an important means in reducing nitrogen loads applied to farmland. Solid phase separation prior to biological treatment further allows for recovering phosphorus with the solid phase. The organic residues from the pig slurry treatment can be applied as organic fertilizers to farmland replacing mineral fertilizers. The environmental impacts of nutrient recycling from aerobic, biological pig slurry treatment were evaluated applying the life cycle assessment (LCA) methodology. LCA results revealed that direct field emissions from organic fertilizer application and the amount of avoided mineral fertilizers dominated the environmental impacts. A modified plant available nitrogen calculation (PAN) was introduced taking into account calculated nitrogen emissions from organic fertilizer application. Additionally, an equation for calculating the quantity of avoided mineral fertilizers based on the modified PAN calculation was proposed, which accounted for nitrogen emissions from mineral fertilizer application.

  7. Removal of nutrient and pesticides from tile drainage discharge using an end-of-tile cartridge approach

    Science.gov (United States)

    Nutrient transport from subsurface tile drainage is pretty well documented. One approach receiving consideration for reducing the amount of nutrients and pesticides in subsurface drainage waters is end-of-tile filters. The filters are often comprised of industrial wastes or by-products that have a s...

  8. Sludge Retention Time as a Suitable Operational Parameter to Remove Both Estrogen and Nutrients in an Anaerobic–Anoxic–Aerobic Activated Sludge System

    OpenAIRE

    Zeng, Qingling; Li, Yongmei; Yang, Shijia

    2013-01-01

    Estrogen in wastewater are responsible for a significant part of the endocrine-disrupting effects observed in the aquatic environment. The effect of sludge retention time (SRT) on the removal and fate of 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) in an anaerobic–anoxic–oxic activated sludge system designed for nutrient removal was investigated by laboratory-scale experiments using synthetic wastewater. With a hydraulic retention time of 8 h, when SRT ranged 10–25 days, E2 was almost co...

  9. Removal of reactive blue 19 from wastewaters by physicochemical and biological processes - a review

    International Nuclear Information System (INIS)

    The developments for the removal of reactive blue 19 dye (RB 19) by various physicochemical methods such as sonolysis, photo catalysis, electrochemical, ozonolysis, adsorption, hydrolysis and biological methods like microbial degradation, bio sorption, chemical and biological reductive decolorisation has been presented. It was found that none of the individual physical and chemical technique can be used in wastewater treatment with good economics and high energy efficiency. For example, the application of adsorption method is restricted as adsorbent materials requires frequent regenerations; ozonolysis and photo catalysis processes can efficiently decolorize and degrade the dye but these face operational difficulties are not cost effective. Similarly the performance of biological treatment processes is required to enhance by developing efficient strains of bacteria, fungi. The comparison of physiochemical and biological treatment of RB 19 dye suggested that biological treatment of RB 19 dye is comparatively cost-effective process. However, the integrated approach can be used to decolorize and degrade the dye by combining both physicochemical and biological processes. (author)

  10. Integrated physicochemical and biological treatment process for fluoride and phosphorus removal from fertilizer plant wastewater.

    Science.gov (United States)

    Gouider, Mbarka; Mlaik, Najwa; Feki, Mongi; Sayadi, Sami

    2011-08-01

    The phosphate fertilizer industry produces highly hazardous and acidic wastewaters. This study was undertaken to develop an integrated approach for the treatment of wastewaters from the phosphate industry. Effluent samples were collected from a local phosphate fertilizer producer and were characterized by their high fluoride and phosphate content. First, the samples were pretreated by precipitation of phosphate and fluoride ions using hydrated lime. The resulting low- fluoride and phosphorus effluent was then treated with the enhanced biological phosphorus removal (EBPR) process to monitor the simultaneous removal of carbon, nitrogen, and phosphorus. Phosphorus removal included a two-stage anaerobic/aerobic system operating under continuous flow. Pretreated wastewater was added to the activated sludge and operated for 160 days in the reactor. The operating strategy included increasing the organic loading rate (OLR) from 0.3 to 1.2 g chemical oxygen demand (COD)/L.d. The stable and high removal rates of COD, NH4(+)-N, and PO4(3-)-P were then recorded. The mean concentrations of the influent were approximately 3600 mg COD/L, 60 mg N/L, and 14 mg P/L, which corresponded to removal efficiencies of approximately 98%, 86%, and 92%, respectively. PMID:21905410

  11. Evaluation of In-situ Sludge Reduction and Enhanced Nutrient Removal in an Integrated Repeatedly Coupling Aerobic and Anaerobic and Oxic-setting-anaerobic System

    Institute of Scientific and Technical Information of China (English)

    Shanshan Yang; Wanqian Guo; Qinglian Wu; Haichao Luo; Simai Peng; Heshan Zheng; Xiaochi Feng; Nanqi Ren∗

    2015-01-01

    Aiming to achieve simultaneous good performances of in⁃situ sludge reduction and effluent quality, an integrated repeatedly coupling aerobic and anaerobic and oxic⁃setting⁃anaerobic system ( rCAA+OSA ) is developed to reduce sludge production and enhance nutrient removal. Considering the mechanism of in⁃situ sludge reduction in this rCAA+OSA system, the combined effect of energy uncoupling metabolism and sludge cryptic growth maybe attributed to the higher reduction of biomass. Results show that the maximal sludge reduction in this rCAA+OSA system is obtained when the hydraulic retention time ( HRT ) is controlled at 6�5 h, which an increase in 16�67% reduction in excess sludge is achieved compared with OSA system ( HRT of 6�5 h) . When compared the performances of effluent qualities, the enhanced nutrient removal efficiencies also can be observed in this rCAA+OSA system. Three⁃dimensional excitation emission matrix ( 3D⁃EEM ) fluorescence spectroscopy is applied to characterize the effluent organic matters ( EfOM) under different HRTs in the OSA and the rCAA+OSA systems. Analyses of 3D⁃EEM spectra show that more refractory humic⁃like and fulvic⁃like components are observed in the effluent of the OSA system. On the basis of these results, simultaneous enhanced in⁃situ sludge reduction and improved nutrient removal can be obtained in the rCAA+OSA systems.

  12. 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.

    Science.gov (United States)

    Maliki, Raphiou; Sinsin, Brice; Floquet, Anne; Cornet, Denis; Malezieux, Eric; Vernier, Philippe

    2016-01-01

    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. PMID:27446635

  13. 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

    Science.gov (United States)

    Sinsin, Brice; Floquet, Anne; Cornet, Denis; Malezieux, Eric; Vernier, Philippe

    2016-01-01

    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. PMID:27446635

  14. 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.

  15. Optimization of biological phosphorus and ammonia removal in a combined fixed and suspended growth wastewater treatment system: Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    This project was conducted to optimize design and operational criteria for enhanced biological phosphorus removal and nitrification of ammonia in the fixed growth reactor-suspended growth reactor (FGR-SGR) process. The research completed the investigation of optimum hydraulic retention times for biological phosphorus removal in both the unaerated and aerated phases of the suspended growth components of the FGR-SGR system, including an assessment of the possibility of reducing suspended growth aeration requirements by using oxidized forms of nitrogen rather than dissolved oxygen for biological phosphorus uptake; investigated the effects on biological phosphorus removal and nitrification of varying the internal recycle flow rates; and investigated the optimum solids retention time, or the optimum operating mixed liquor suspended solids concentration, in the suspended growth component of the system for biological phosphorus removal and nitrification-denitrification.

  16. Modeling the Performance of Biological Rapid Sand Filters Used to Remove Ammonium, Iron, and Manganese From Drinking Water

    DEFF Research Database (Denmark)

    Lee, Carson; Albrechtsen, Hans-Jørgen; Smets, Barth F.;

    Although biological rapid sand filters are a well established technology for treating drinking water, there is still a lack of scientific understanding of the processes controlling their performance. For example, the distribution and role of microorganisms in contaminant removal in the filter has...... filter management to performance . Biological rapid sand filters are used for the dual purpose of particle removal (including microorganisms) and contaminant removal through biological activity on the filter media. For drinking water treatment in the United States, biological filters use granular...... for chlorine addition following treatment. Under the normal conditions found in many water treatment plants, reduced iron can be oxidized through aeration and the precipitates can be captured by the filter media. Ammonium and manganese can be removed biologically. This research uses both pilot and full scale...

  17. Biological and photocatalytic treatment integrated with separation and reuse of titanium dioxide on the removal of chlorophenols in tap water

    Energy Technology Data Exchange (ETDEWEB)

    Suryaman, Dhanus, E-mail: dhanussuryaman@yahoo.com [Agency for the Assessment and Application of Technology, M.H. Thamrin No. 8, Jakarta 10340 (Indonesia); Department of Chemical and Biochemical Engineering, Faculty of Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555 (Japan); Hasegawa, Kiyoshi [Department of Chemical and Biochemical Engineering, Faculty of Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555 (Japan)

    2010-11-15

    We investigated biological, photocatalytic, and combination of biological and photocatalytic treatments in order to remove a mixture of 2-chlorophenol, 2,4-dichlorophenol, 2,4,5-trichlorophenol, and pentachlorophenol in tap water (total: 100 mg L{sup -1}, each: 25 mg L{sup -1}). The removal of chlorinated phenols was conducted with a flow biological treatment and a circulative flow photocatalytic treatment under black light and sunlight irradiations integrated with titanium dioxide separation and reuse. The combined biological-photocatalytic treatment significantly shortened the degradation and mineralization time of both the biological treatment and the photocatalytic treatment. The removed chlorophenols per hour by the combined biological-photocatalytic treatment was 25.8 mg h{sup -1}, whereas by the combined photocatalytic-biological treatment was 10.5 mg h{sup -1}. After a large portion of biodegradable 2-chlorophenol and 2,4-dichlorophenol, and around half amount of slightly biodegradable 2,4,5-trichlorophenol were removed by the biological treatment, the remained three chlorophenols, biorecalcitrant pentachlorophenol, and biodegradation products were completely removed by the subsequent photocatalytic treatment. Since titanium dioxide particles in tap water spontaneously sedimented on standing after the photocatalytic treatment, the combined treatment can be operated by integrating with the titanium dioxide separation and reuse. The TiO{sub 2} particles were recovered and reused at least three times without significantly decreasing the removal efficiency.

  18. Biological and photocatalytic treatment integrated with separation and reuse of titanium dioxide on the removal of chlorophenols in tap water

    International Nuclear Information System (INIS)

    We investigated biological, photocatalytic, and combination of biological and photocatalytic treatments in order to remove a mixture of 2-chlorophenol, 2,4-dichlorophenol, 2,4,5-trichlorophenol, and pentachlorophenol in tap water (total: 100 mg L-1, each: 25 mg L-1). The removal of chlorinated phenols was conducted with a flow biological treatment and a circulative flow photocatalytic treatment under black light and sunlight irradiations integrated with titanium dioxide separation and reuse. The combined biological-photocatalytic treatment significantly shortened the degradation and mineralization time of both the biological treatment and the photocatalytic treatment. The removed chlorophenols per hour by the combined biological-photocatalytic treatment was 25.8 mg h-1, whereas by the combined photocatalytic-biological treatment was 10.5 mg h-1. After a large portion of biodegradable 2-chlorophenol and 2,4-dichlorophenol, and around half amount of slightly biodegradable 2,4,5-trichlorophenol were removed by the biological treatment, the remained three chlorophenols, biorecalcitrant pentachlorophenol, and biodegradation products were completely removed by the subsequent photocatalytic treatment. Since titanium dioxide particles in tap water spontaneously sedimented on standing after the photocatalytic treatment, the combined treatment can be operated by integrating with the titanium dioxide separation and reuse. The TiO2 particles were recovered and reused at least three times without significantly decreasing the removal efficiency.

  19. Removal of anaerobic soluble microbial products in a biological activated carbon reactor

    Institute of Scientific and Technical Information of China (English)

    Xiaojing Dong; Weili Zhou; Shengbing He

    2013-01-01

    The soluble microbial products (SMP) in the biological treatment effluent are generally of great amount and are poorly biodegradable.Focusing on the biodegradation of anaerobic SMP,the biological activated carbon (BAC) was introduced into the anaerobic system.The experiments were conducted in two identical lab-scale up-flow anaerobic sludge blanket (UASB) reactors.The high strength organics were degraded in the first UASB reactor (UASB1) and the second UASB (UASB2,i.e.,BAC) functioned as a polishing step to remove SMP produced in UASB1.The results showed that 90% of the SMP could be removed before granular activated carbon was saturated.After the saturation,the SMP removal decreased to 60% on the average.Analysis of granular activated carbon adsorption revealed that the main role of SMP removal in BAC reactor was biodegradation.A strain of SMP-degrading bacteria,which was found highly similar to Klebsiella sp.,was isolated,enriched and inoculated back to the BAC reactor.When the influent chemical oxygen demand (COD) was 10,000 mg/L and the organic loading rate achieved 10 kg COD/(m3·day),the effluent from the BAC reactor could meet the discharge standard without further treatment.Anaerobic BAC reactor inoculated with the isolated Klebsiella was proved to be an effective,cheap and easy technical treatment approach for the removal of SMP in the treatment of easily-degradable wastewater with COD lower than 10,000 mg/L.

  20. Enhanced biological phosphorus removal - results of experiences in three large waste water treatment plants. Biologische Phosphatelimination - Betriebserfahrungen an drei Grossanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, P. (Fachbereich Bauingenieurwesen, FG Siedlungswasserwirtschaft, Kassel Univ. (Gesamthochschule) (Germany)); Telgmann, U. (Fachbereich Bauingenieurwesen, FG Siedlungswasserwirtschaft, Kassel Univ. (Gesamthochschule) (Germany)); Memmen, K. (Fachbereich Bauingenieurwesen, FG Siedlungswasserwirtschaft, Kassel Univ. (Gesamthochschule) (Germany))

    1994-09-01

    Within a scientific project especially the operation of four real-size sewage treatment plants with different processes of enhanced biological phosphorus removal is investigated under the aspect of efficiency, stability, practicability and costs of the enhanced biological phosphorus removal. Three plants and first results are explained and compared as well with one another as with data, which are generally regarded as favourable conditions for the enhanced biological phosphorus removal. Between the plants there are significant differences in the degree of P-elimination mainly due to different characteristics of the wastewater. An important influence on P-effluent concentrations may be exacted by P-resolution in the final clarifier. (orig.)

  1. Removal of stigmasterol from Kraft mill effluent by aerobic biological treatment with steroidal metabolite detection.

    Science.gov (United States)

    Chamorro, Soledad; Vergara, Juan P; Jarpa, Mayra; Hernandez, Victor; Becerra, Jose; Vidal, Gladys

    2016-10-14

    Stigmasterol is a phytosterol contained in Kraft mill effluent that is able to increase over 100% after aerobic biological treatment. This compound can act as an endocrine disrupter as its structure is similar to that of cholesterol. The aim of this study was to evaluate the removal of stigmasterol from Kraft mill effluents treated by a moving bed biofilm reactor (MBBR) with steroidal metabolite detection. The MBBR was operated for 145 days, with a hydraulic retention time of 2 days. Stigmasterol and steroidal metabolites were detected by gas chromatography with a flame ionization detector during MBBR operation. The results show that the MBBR removed 87.4% of biological oxygen demand (BOD5), 61.5% of chemical oxygen demand (COD), 24.5% of phenol and 31.5% of lignin, expressed in average values. The MBBR system successfully removed 100% of the stigmasterol contained in the influent (33 µg L(-1)) after 5 weeks of operation. In that case, the organic load rate was 0.343 kg COD m(-3) d(-1). Furthermore, different steroidal compounds (e.g., testosterone propionate, stigmast-4-en-3-one, 5α-pregnan-12-one-20α-hydroxy, 5α-pregnane-3,11,20-trione and 3α-hydroxy-5α-androstane-11,17-dione were detected in the Kraft mill effluent as potential products of phytosterol biotransformation. PMID:27399163

  2. Monitoring of Biological Nitrogen Removal in Tannery Wastewater Using a Sequencing Batch Reactor

    Directory of Open Access Journals (Sweden)

    Carrasquero-Ferrer Sedolfo José

    2014-04-01

    Full Text Available The objective of this research was to relate the biological nitrogen removal in tannery wastewater with profiles of pH, alkalinity and redox potential (ORP using a sequencing batch reactor (SBR with a working volume of 2 L. The reactor worked under two operational sequences: anoxic-aerobic-anoxic (Ax/Ae/Ax and aerobic-anoxic (Ae/Ax, which were combined with two cell retention times (CRT (15 and 25 days, with an operation cycle time (OCT of 11 hours. The profiles were performed by measuring each 15 minutes the following parameters: pH, dissolved oxygen (DO, ORP, and each hour the parameters: total alkalinity, total chemical oxygen demand (DQOT, soluble chemical oxygen demand (DQOS, total Kjeldahl nitrogen (TKN, nitrite (NO2-, nitrate (NO3- and ammonia nitrogen (N-NH4+. Alkalinity and ORP profile were excellent indicators of the processes of biological nitrogen removal. However, pH could not be used as a control parameter, due to the buffering capacity of tannery wastewater. Finally, this research work showed that alkalinity and ORP values can be used as on-line control parameters to monitor the evolution of the nitrogen removal in tannery wastewater (nitrification and denitrification processes.

  3. Biological and Physiochemical Techniques for the Removal of Zinc from Drinking Water: A Review

    Directory of Open Access Journals (Sweden)

    Naseem Zahra

    2015-12-01

    Full Text Available Presence of Zinc (II in drinking water beyond permissible limits is considered unsafe for human health. Many different anthropogenic activities including mining, burning of petroleum, industrialization, and urbanization cause a release of considerably higher amounts of zinc into the waterbodies. A permissible limit of 5 mg/L is set by various environmental and pollution control authorities beyond which water may cause respiratory, liver, gonads, and brain disorders. Due to these health hazards, it is important to remove exceeding amounts of zinc from drinking water. Zinc enters drinking water from various sources such as corrosive pipelines, release of industrial effluents, and metal leaching. Different biological and physiochemical techniques are used to remove zinc involving chemical precipitation, ion exchange, adsorption, biosorbents, distillation, ozonation, and membrane filtration technology. Among these technologies, physical process of adsorption using low cost adsorbents is not only economical but abundant, efficient, and easily available. In present review different physiochemical and biological techniques are discussed for the removal of Zinc from drinking water.

  4. Nearshore biological communities prior to the removal of the Elwha River dams: Chapter 6 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

    Science.gov (United States)

    Rubin, Stephen P.; Miller, Ian M.; Elder, Nancy; Reisenbichler, Reginald R.; Duda, Jeffrey J.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

    2011-01-01

    Increases in sediment delivery to coastal waters are expected following removal of dams on the Elwha River, Washington, potentially increasing sediment deposition on the seafloor and suspended sediment in the water column. Biological communities inhabiting shallow, subtidal depths

  5. A comparative study of the bacterial community in denitrifying and traditional enhanced biological phosphorus removal processes.

    Science.gov (United States)

    Lv, Xiao-Mei; Shao, Ming-Fei; Li, Chao-Lin; Li, Ji; Gao, Xin-Lei; Sun, Fei-Yun

    2014-09-17

    Denitrifying phosphorus removal is an attractive wastewater treatment process due to its reduced carbon source demand and sludge minimization potential. Two lab-scale sequencing batch reactors (SBRs) were operated in alternating anaerobic-anoxic (A-A) or anaerobic-oxic (A-O) conditions to achieve denitrifying enhanced biological phosphate removal (EBPR) and traditional EBPR. No significant differences were observed in phosphorus removal efficiencies between A-A SBR and A-O SBR, with phosphorus removal rates being 87.9% and 89.0% respectively. The community structures in denitrifying and traditional EBPR processes were evaluated by high-throughput sequencing of the PCR-amplified partial 16S rRNA genes from each sludge. The results obtained showed that the bacterial community was more diverse in A-O sludge than in A-A sludge. Taxonomy and β-diversity analyses indicated that a significant shift occurred in the dominant microbial community in A-A sludge compared with the seed sludge during the whole acclimation phase, while a slight fluctuation was observed in the abundance of the major taxonomies in A-O sludge. One Dechloromonas-related OTU outside the 4 known Candidatus "Accumulibacter" clades was detected as the main OTU in A-A sludge at the stationary operation, while Candidatus "Accumulibacter" dominated in A-O sludge. PMID:24964811

  6. Impact of butyrate on microbial selection in enhanced biological phosphorus removal systems.

    Science.gov (United States)

    Begum, Shamim A; Batista, Jacimaria R

    2014-01-01

    Microbial selection in an enhanced biological phosphorus removal system was investigated in a laboratory-scale sequencing batch reactor fed exclusively with butyrate as a carbon source. As reported in the few previous studies, butyrate uptake was slow and phosphorus (P) release occurred during the entire anaerobic period. Polyphosphate-accumulating organism (PAO), i.e. Candidatus Accumulibacter phosphatis (named as Accumulibacter), glycogen-accumulating organisms (GAOs), i.e. Candidatus Competibacter phosphatis (named as Competibacter) and Defluviicoccus-related, tetrad-forming alphaproteobacteria (named as Defluviicoccus) were identified using fluorescence in situ hybridization analysis. The results show that Accumulibacter and Defluviicoccus were selected in the butyrate-fed reactor, whereas Competibacter was not selected. P removal was efficient at the beginning of the experiment with an increasing percentage relative abundance (% RA) of PAOs. The % RA of Accumulibacter and Defluviicoccus increased from 13% to 50% and 8% to 16%, respectively, and the % RA of Competibacter decreased from 8% to 2% during the experiment. After 6 weeks, P removal deteriorated with the poor correlation between the percentage of P removal and % RA of GAOs. PMID:25189844

  7. Biologically active carbon filtration for haloacetic acid removal from swimming pool water.

    Science.gov (United States)

    Tang, Hao L; Xie, Yuefeng F

    2016-01-15

    A biologically activate carbon (BAC) filter was continuously operated on site for the treatment of haloacetic acids (HAAs) in an outdoor swimming pool at an average empty bed contact time (EBCT) of 5.8 min. Results showed that BAC filtration was a viable technology for direct removal of HAAs from the pool water with a nominal efficiency of 57.7% by the filter while the chlorine residuals were 1.71 ± 0.90 mg/L during the study. THMs and TOC were not removed and thus were not considered as indicators of the effectiveness of BAC filtration. Increased EBCT in the range of 4.5 and 6.4 min led to improved HAA removal performance, which could be best fit by a logarithmic regression model. BAC filtration also affected the HAA speciation by removing more dichloroacetic acid (DCAA) than trichloroacetic acid (TCAA), resulting in a lower ratio of DCAA/TCAA in the filtered effluent. However, the observation of an overall constant ratio could be attributable to a complex formation and degradation mechanism occurring in swimming pools.

  8. Effect of preozonation on biological stability and organic matter removal from water

    Directory of Open Access Journals (Sweden)

    ZHANG Hongzhuan

    2014-12-01

    Full Text Available Both preozonation and prechlorination processes were adopted before the conventional drinking water treatment process,and the raw water for each was taken from upstream of Huangpu River.The comparative pilot experiments were conducted at a scale of 1.0 m3·h-1 for each.CODMn,UV254,TOC,and AOC of the finished water were determined after the preozonation process,compared with those after the prechlorination process.The Effect of the preozonation process on organic material removal from water was studied.The biological stability of the finished water after the preozonation process was analyzed.The results show that when CODMn in raw water was 5.56~6.50 m3·L-1,CODMn removal efficiency and UV254 removal rate by pre-ozonation process increased by 2.5% and 6%,respectively,compared with those by pre-chlorination process.TOC removal efficiencies by both processes were not high.AOC in the finished water after the preozonation process was higher obviously than that after the prechlorination process.

  9. A combined biological removal of Cd(2+) from aqueous solutions using Phanerochaete chrysosporium and rice straw.

    Science.gov (United States)

    Zhao, Meihua; Zhang, Chaosheng; Zeng, Guangming; Cheng, Min; Liu, Yang

    2016-08-01

    The removal of Cd(2+) from aqueous solutions by agricultural residues rice straw combined with white rot fungus Phanerochaete chrysosporium (P. chrysosporium) was investigated. The results showed that over 99% of the total Cd(2+) (initial concentration of 150mgL(-1)) was removed at the optimal operating conditions (pH 5.0 at 35°C). We also found that P. chrysosporium could survive under Cd(2+) stress even with an initial Cd(2+) concentration of 250mgL(-1). But when Cd(2+) concentration increased to 250mgL(-1), fungus growth and reproduction were remarkably restrained, and as a result, Cd(2+) removal dropped to 59.2%. It was observed that the fungus biomass and activities of ligninolytic enzymes decreased at some degree under high concentration of Cd(2+) (above 100mgL(-1)). Also, we found that a moderate Cd(2+) stress (below 150mgL(-1)) could stimulate P. chrysosporium's production of the heavy metals chelator - oxalate. This study will provide useful information for the application of biological removal of heavy metal irons from wastewater.

  10. Enrichment and immobilization of sulfide removal microbiota applied for environmental biological remediation of aquaculture area.

    Science.gov (United States)

    Zhao, Yang-Guo; Zheng, Yu; Tian, Weijun; Bai, Jie; Feng, Gong; Guo, Liang; Gao, Mengchun

    2016-07-01

    To remove sulfide in the deteriorating aquaculture sediment and water, sulfide-oxidizing microbiota was enriched from Jiaozhou Bay, China, by using sulfide-rich medium. Composition and structure of microbial communities in the enrichments were investigated by 16S rDNA molecular biotechniques. Results showed that microbial community structure continuously shifted and the abundance of sulfate reducing bacteria, i.e., Desulfobacterium, Desulfococcus and Desulfobacca apparently declined. Several halophile genera, Vibrio, Marinobacter, Pseudomonas, Prochlorococcus, Pediococcus and Thiobacillus predominated finally in the microbiota. The enriched microbiota was capable of removing a maximum of 1000 mg/L sulfide within 12 h with 10% inoculum at pH 7.0, 20-30 °C. After immobilized, the microbiota presented excellent resistance to impact and could completely remove 600 mg/L sulfide in 12 h. Moreover, the immobilized microbiota recovered well even recycled for five times. In conclusion, the immobilized sulfide-removing microbiota showed a quite promising application for biological restoring of sulfide-rich aquaculture environment. PMID:27105167

  11. Effect of hydraulic retention time on inorganic nutrient recovery and biodegradable organics removal in a biofilm reactor treating plant biomass leachate

    Science.gov (United States)

    Krumins, Valdis; Hummerick, Mary; Levine, Lanfang; Strayer, Richard; Adams, Jennifer L.; Bauer, Jan

    2002-01-01

    A fixed-film (biofilm) reactor was designed and its performance was determined at various retention times. The goal was to find the optimal retention time for recycling plant nutrients in an advanced life support system, to minimize the size, mass, and volume (hold-up) of a production model. The prototype reactor was tested with aqueous leachate from wheat crop residue at 24, 12, 6, and 3 h hydraulic retention times (HRTs). Biochemical oxygen demand (BOD), nitrates and other plant nutrients, carbohydrates, total phenolics, and microbial counts were monitored to characterize reactor performance. BOD removal decreased significantly from 92% at the 24 h HRT to 73% at 3 h. Removal of phenolics was 62% at the 24 h retention time, but 37% at 3 h. Dissolved oxygen concentrations, nitric acid consumption, and calcium and magnesium removals were also affected by HRT. Carbohydrate removals, carbon dioxide (CO2) productions, denitrification, potassium concentrations, and microbial counts were not affected by different retention times. A 6 h HRT will be used in future studies to determine the suitability of the bioreactor effluent for hydroponic plant production.

  12. Effect of hydraulic retention time on inorganic nutrient recovery and biodegradable organics removal in a biofilm reactor treating plant biomass leachate

    Energy Technology Data Exchange (ETDEWEB)

    Krumins, V.; Hummerick, M.; Levine, L.; Strayer, R.; Adams, J.L.; Bauer, J. [Dynamac Corporation, Kennedy Space Center, FL (United States)

    2002-12-01

    A fixed-film (biofilm) reactor was designed and its performance was determined at various retention times. The goal was to find the optimal retention time for recycling plant nutrients in an advanced life support system, to minimize the size, mass, and volume (hold-up) of a production model. The prototype reactor was tested with aqueous leachate from wheat crop residue at 24, 12, 6, and 3 h hydraulic retention times (HRTs). Biochemical oxygen demand (BOD), nitrates and other plant nutrients, carbohydrates, total phenolics, and microbial counts were monitored to characterize reactor performance. BOD removal decreased significantly from 92% at the 24 h HRT to 73% at 3 h. Removal of phenolics was 62% at the 24 h retention time, but 37% at 3 h. Dissolved oxygen concentrations, nitric acid consumption, and calcium and magnesium removals were also affected by HRT. Carbohydrate removals, carbon dioxide (CO{sub 2}) productions, denitrification, potassium concentrations, and microbial counts were not affected by different retention times. A 6 h HRT will be used in future studies to determine the suitability of the bioreactor effluent for hydroponic plant production. (author)

  13. Biological treatment process for removing petroleum hydrocarbons from oil field produced waters

    Energy Technology Data Exchange (ETDEWEB)

    Tellez, G.; Khandan, N.

    1995-12-31

    The feasibility of removing petroleum hydrocarbons from oil fields produced waters using biological treatment was evaluated under laboratory and field conditions. Based on previous laboratory studies, a field-scale prototype system was designed and operated over a period of four months. Two different sources of produced waters were tested in this field study under various continuous flow rates ranging from 375 1/D to 1,800 1/D. One source of produced water was an open storage pit; the other, a closed storage tank. The TDS concentrations of these sources exceeded 50,000 mg/l; total n-alkanes exceeded 100 mg/l; total petroleum hydrocarbons exceeded 125 mg/l; and total BTEX exceeded 3 mg/l. Removals of total n-alkanes, total petroleum hydrocarbons, and BTEX remained consistently high over 99%. During these tests, the energy costs averaged $0.20/bbl at 12 bbl/D.

  14. Achieving and maintaining biological nitrogen removal via nitrite under normal conditions

    Institute of Scientific and Technical Information of China (English)

    CUI You-wei; PENG Yong-zhen; GAN Xiang-qing; YE Liu; WANG Ya-yi

    2005-01-01

    The principal aim of this paper is to develop an approach to realize stable biological nitrogen removal via nitrite under normal conditions. Validation of the new method was established on laboratory-scale experiments applying the sequencing batch reactor(SBR)activated sludge process to domestic wastewater with low C/N ratio. The addition of sodium chloride(NaCl) to influent was established to achieve nitrite build-up. The high nitrite accumulation, depending on the salinity in influent and the application duration of salt, was obtained in SBRs treating saline wastewater. The maintenance results indicated that the real-time SBRs can maintain stable nitrite accumulation, but conversion from shorter nitrification-denitrification to full nitrification-denitrification was observed after some operation cycles in the other SBR with fixed-time control. The presented method is valuable to offer a solution to realize and to maintain nitrogen removal via nitrite under normal conditions.

  15. Removal of hydrogen sulfide from gas streams using biological processes : a review

    Energy Technology Data Exchange (ETDEWEB)

    Syed, M.; Soreanu, G.; Falletta, P.; Beland, M. [Environment Canada, Burlington, ON (Canada). Wastewater Technology Centre

    2006-07-01

    Hydrogen sulfide (H{sub 2}S) is produced by the anaerobic digestion of biosolids and other organic materials, and can be corrosive to internal combustion engines. This study investigated biological H{sub 2}S removal processes with the aim of overcoming the chemical and disposal costs associated with existing chemically-based removal processes. Current biological H{sub 2}S removal processes were reviewed, and research needs for potential process improvements were identified. Processes included photoautotrophs; chemotrophs; bioreactors for H{sub 2}S removal involving phototrophic bacteria; continuous-flow reactors; phototube reactors; gas-fed batch reactors; bioscrubbers; biofilters; and biotrickling filters. Results of the review suggested that the preferred treatment method for H{sub 2}S gas containing streams depended on the source of the gas. In the case of H{sub 2}S in biogas, anaerobic methods involving phototrophic bacteria provided the inherent advantage of maintaining the anaerobic nature of the gas. Cholorobium limicola was recommended as a desirable bacterium due to its growth using inorganic substrates, its efficiency at converting sulfide to elemental sulfur, and its extracellular production of elemental sulfur. Fixed-film reactors had the greatest potential for cost-effective sulfide conversion. It was noted that light supply is one of the key cost components in the process and poses a major constraint. It was concluded that future research should focus on the development and use of energy efficient LEDs and the proper use of sunlight and reflectors to minimize the electrical energy use. 73 refs., 5 tabs., 5 figs.

  16. Biological sulfate removal from construction and demolition debris leachate: Effect of bioreactor configuration

    Energy Technology Data Exchange (ETDEWEB)

    Kijjanapanich, Pimluck, E-mail: som_cheng00@hotmail.com [Pollution Prevention and Resource Recovery Chair Group, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft (Netherlands); Do, Anh Tien [Civil and Environmental Engineering, University of South Florida, Tampa, FL 33620 (United States); Annachhatre, Ajit P. [Environmental Engineering and Management, Asian Institute of Technology, PO Box 4, Klongluang, Pathumthani 12120 (Thailand); Esposito, Giovanni [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio 43, 03043 Cassino (Italy); Yeh, Daniel H. [Civil and Environmental Engineering, University of South Florida, Tampa, FL 33620 (United States); Lens, Piet N.L. [Pollution Prevention and Resource Recovery Chair Group, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft (Netherlands)

    2014-03-01

    Highlights: • Novel biological technique for gypsum removal from CDD. • CDDS leachate treatment performed using different sulfate reducing bioreactors. • Gypsum in CDD can be used as a source of sulfate for sulfate reducing bacteria. • High calcium concentration (1000 mg L{sup −1}) did not affect the bioreactor performance. - Abstract: Due to the contamination of construction and demolition debris (CDD) by gypsum drywall, especially, its sand fraction (CDD sand, CDDS), the sulfate content in CDDS exceeds the posed limit of the maximum amount of sulfate present in building sand (1.73 g sulfate per kg of sand for the Netherlands). Therefore, the CDDS cannot be reused for construction. The CDDS has to be washed in order to remove most of the impurities and to obtain the right sulfate content, thus generating a leachate, containing high sulfate and calcium concentrations. This study aimed at developing a biological sulfate reduction system for CDDS leachate treatment and compared three different reactor configurations for the sulfate reduction step: the upflow anaerobic sludge blanket (UASB) reactor, inverse fluidized bed (IFB) reactor and gas lift anaerobic membrane bioreactor (GL-AnMBR). This investigation demonstrated that all three systems can be applied for the treatment of CDDS leachate. The highest sulfate removal efficiency of 75–85% was achieved at a hydraulic retention time (HRT) of 15.5 h. A high calcium concentration up to 1000 mg L{sup −1} did not give any adverse effect on the sulfate removal efficiency of the IFB and GL-AnMBR systems.

  17. Performance of biological phosphorus removal and characteristics of microbial community in the oxic-settling-anaerobic process by FISH analysis

    Institute of Scientific and Technical Information of China (English)

    Jian-fang WANG; Qing-liang ZHAO; Wen-biao JIN; Shi-jie YOU; Jin-na ZHANG

    2008-01-01

    Performance of biological phosphorus removal in the oxic-settling-anaerobic (OSA) process was investigated. Cell staining and fluorescent in situ hybridization (FISH) were used to analyze characteristics and microbial community of sludge.Experimental results showed that phosphorus removal efficiency was near 60% and the amount of biological phosphorus accumulation in aerobic sludge of the OSA system was up to 26.9 mg/g. Biological phosphorus removal efficiency was partially inhibited by carbon sources in the continuous OSA system. Contrasted to the OSA system, biological phosphorus removal efficiency was enhanced by 14% and the average total phosphorus (TP) contents of aerobic sludge were increased by 0.36 mg/g when sufficient carbon sources were supplied in batch experiments. Staining methods indicated that about 35% of microorganisms had typical characteristics of phosphorus accumulating organisms (PAOs). FISH analysis demonstrated that PAOMIX-binding bacteria were predominant microbial communities in the OSA system, which accounted for around 28% of total bacteria.

  18. Effect of solids retention time and wastewater characteristics on biological phosphorus removal

    DEFF Research Database (Denmark)

    Henze, Mogens; Aspegren, H.; Jansen, J.l.C.;

    2002-01-01

    The paper deals with the effect of wastewater, plant design and operation in relation to biological nitrogen and phosphorus removal and the possibilities to model the processes. Two Bio-P pilot plants were operated for 2.5 years in parallel receiving identical wastewater. The plants had SRT of 4...... in the settler. The addition of glucose to the influent seems to have an effect on the performance of the plants similar to that of acetic acid. In spite of great load variations over time to the pilot plants and the different operational modes, the study of population dynamics showed less significant variations...

  19. Application of vascular aquatic plants for pollution removal, energy and food production in a biological system

    Science.gov (United States)

    Wolverton, B. C.; Barlow, R. M.; Mcdonald, R. C.

    1975-01-01

    Vascular aquatic plants such as water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb., when utilized in a controlled biological system (including a regular program of harvesting to achieve maximum growth and pollution removal efficiency), may represent a remarkably efficient and inexpensive filtration and disposal system for toxic materials and sewage released into waters near urban and industrial areas. The harvested and processed plant materials are sources of energy, fertilizer, animal feed, and human food. Such a system has industrial, municipal, and agricultural applications.

  20. Removal of Natural Organic Matter Fractions by Anion Exchange: Impact on drinking water treatment processes and biological stability

    NARCIS (Netherlands)

    Grefte, A.

    2013-01-01

    This researched focused on improving drinking water quality, specifically the biological stability of the produced drinking water. Natural organic matter (NOM) can be a source of nutrients for bacteria present in the distribution system, which can cause regrowth. Specifically, small organic acids ca

  1. Removal of diclofenac from surface water by electron beam irradiation combined with a biological aerated filter

    Science.gov (United States)

    He, Shijun; Wang, Jianlong; Ye, Longfei; Zhang, Youxue; Yu, Jiang

    2014-12-01

    The degradation of DCF was investigated in aqueous solution by using electron beam (EB) technology. When the initial concentration was between 10 and 40 mg/L, almost 100% of the DCF was degraded at a dose of 0.5 kGy. However, only about 6.5% of DCF was mineralized even at 2 kGy according to total organic carbon (TOC) measurements. A combined process of EB and biological aerated filter (BAF) was therefore developed to enhance the treatment of DCF contaminated surface water. The effluent quality of combined process was substantially improved by EB pretreatment due to the degradation of DCF and related intermediates. Both irradiation and biological treatment reduced the toxicity of the treated water. The experimental results showed that EB is effective for removing DCF from artificial aqueous solution and real surface water.

  2. Intensification of ammonia removal from waste water in biologically active zeolitic ion exchange columns.

    Science.gov (United States)

    Almutairi, Azel; Weatherley, Laurence R

    2015-09-01

    The use of nitrification filters for the removal of ammonium ion from waste-water is an established technology deployed extensively in municipal water treatment, in industrial water treatment and in applications such as fish farming. The process involves the development of immobilized bacterial films on a solid packing support, which is designed to provide a suitable host for the film, and allow supply of oxygen to promote aerobic action. Removal of ammonia and nitrite is increasingly necessary to meet drinking water and discharge standards being applied in the US, Europe and other places. Ion-exchange techniques are also effective for removal of ammonia (as the ammonium ion) from waste water and have the advantage of fast start-up times compared to biological filtration which in some cases may take several weeks to be fully operational. Here we explore the performance of ion exchange columns in which nitrifying bacteria are cultivated, with the goal of a "combined" process involving simultaneous ion-exchange and nitrification, intensified by in-situ aeration with a novel membrane module. There were three experimental goals. Firstly, ion exchange zeolites were characterized and prepared for comparative column breakthrough studies for ammonia removal. Secondly effective in-situ aeration for promotion of nitrifying bacterial growth was studied using a number of different membranes including polyethersulfone (PES), polypropylene (PP), nylon, and polytetra-fluoroethylene (PTFE). Thirdly the breakthrough performance of ion exchange columns filled with zeolite in the presence of aeration and in the presence of nitrifying bacteria was determined to establish the influence of biomass, and aeration upon breakthrough during ammonium ion uptake. The methodology adopted included screening of two types of the naturally occuring zeolite clinoptilolite for effective ammonia removal in continuous ion-exchange columns. Next, the performance of fixed beds of clinoptilolite in the

  3. Intensification of ammonia removal from waste water in biologically active zeolitic ion exchange columns.

    Science.gov (United States)

    Almutairi, Azel; Weatherley, Laurence R

    2015-09-01

    The use of nitrification filters for the removal of ammonium ion from waste-water is an established technology deployed extensively in municipal water treatment, in industrial water treatment and in applications such as fish farming. The process involves the development of immobilized bacterial films on a solid packing support, which is designed to provide a suitable host for the film, and allow supply of oxygen to promote aerobic action. Removal of ammonia and nitrite is increasingly necessary to meet drinking water and discharge standards being applied in the US, Europe and other places. Ion-exchange techniques are also effective for removal of ammonia (as the ammonium ion) from waste water and have the advantage of fast start-up times compared to biological filtration which in some cases may take several weeks to be fully operational. Here we explore the performance of ion exchange columns in which nitrifying bacteria are cultivated, with the goal of a "combined" process involving simultaneous ion-exchange and nitrification, intensified by in-situ aeration with a novel membrane module. There were three experimental goals. Firstly, ion exchange zeolites were characterized and prepared for comparative column breakthrough studies for ammonia removal. Secondly effective in-situ aeration for promotion of nitrifying bacterial growth was studied using a number of different membranes including polyethersulfone (PES), polypropylene (PP), nylon, and polytetra-fluoroethylene (PTFE). Thirdly the breakthrough performance of ion exchange columns filled with zeolite in the presence of aeration and in the presence of nitrifying bacteria was determined to establish the influence of biomass, and aeration upon breakthrough during ammonium ion uptake. The methodology adopted included screening of two types of the naturally occuring zeolite clinoptilolite for effective ammonia removal in continuous ion-exchange columns. Next, the performance of fixed beds of clinoptilolite in the

  4. Contribution of water hyacinth (Eichhornia crassipes (Mart.) Solms) grown under different nutrient conditions to Fe-removal mechanisms in constructed wetlands.

    Science.gov (United States)

    Jayaweera, Mahesh W; Kasturiarachchi, Jagath C; Kularatne, Ranil K A; Wijeyekoon, Suren L J

    2008-05-01

    Severe contamination of water resources including groundwater with iron (Fe) due to various anthropogenic activities has been a major environmental problem in industrial areas of Sri Lanka. Hence, the use of the obnoxious weed, water hyacinth (Eichhornia crassipes (Mart.) Solms) in constructed wetlands (floating aquatic macrophyte-based plant treatment systems) to phytoremediate Fe-rich wastewaters seems to be an appealing option. Although several studies have documented that hyacinths are good metal-accumulating plants none of these studies have documented the ability of this plant grown under different nutrient conditions to remove heavy metals from wastewaters. This paper, therefore, reports the phytoremediation efficiencies of water hyacinth grown under different nutrient conditions for Fe-rich wastewaters in batch-type constructed wetlands. This study was conducted for 15 weeks after 1-week acclimatization by culturing young water hyacinth plants (average height of 20+/-2cm) in 590L capacity fiberglass tanks under different nutrient concentrations of 1-fold [28 and 7.7mg/L of total nitrogen (TN) and total phosphorous (TP), respectively], 2-fold, 1/2-fold, 1/4-fold and 1/8-fold with synthetic wastewaters containing 9.27Femg/L. Another set-up of hyacinths containing only Fe as a heavy metal but without any nutrients (i.e., 0-fold) was also studied. A mass balance was carried out to investigate the phytoremediation efficiencies and to determine the different mechanisms governing Fe removal from the wastewaters. Fe removal was largely due to phytoremediation mainly through the process of rhizofiltration and chemical precipitation of Fe2O3 and FeOH3 followed by flocculation and sedimentation. However, chemical precipitation was more significant especially during the first 3 weeks of the study. Plants grown in the 0-fold set-up showed the highest phytoremediation efficiency of 47% during optimum growth at the 6th week with a highest accumulation of 6707Femg/kg dry

  5. Comparative study on nutrient removal of agricultural non-point source pollution for three filter media filling schemes in eco-soil reactors.

    Science.gov (United States)

    Du, Fuyi; Xie, Qingjie; Fang, Longxiang; Su, Hang

    2016-08-01

    Nutrients (nitrogen and phosphorus) from agricultural non-point source (NPS) pollution have been increasingly recognized as a major contributor to the deterioration of water quality in recent years. The purpose of this article is to investigate the discrepancies in interception of nutrients in agricultural NPS pollution for eco-soil reactors using different filling schemes. Parallel eco-soil reactors of laboratory scale were created and filled with filter media, such as grit, zeolite, limestone, and gravel. Three filling schemes were adopted: increasing-sized filling (I-filling), decreasing-sized filling (D-filling), and blend-sized filling (B-filling). The systems were intermittent operations via simulated rainstorm runoff. The nutrient removal efficiency, biomass accumulation and vertical dissolved oxygen (DO) distribution were defined to assess the performance of eco-soil. The results showed that B-filling reactor presented an ideal DO for partial nitrification-denitrification across the eco-soil, and B-filling was the most stable in the change of bio-film accumulation trends with depth in the three fillings. Simultaneous and highest removals of NH4(+)-N (57.74-70.52%), total nitrogen (43.69-54.50%), and total phosphorus (42.50-55.00%) were obtained in the B-filling, demonstrating the efficiency of the blend filling schemes of eco-soil for oxygen transfer and biomass accumulation to cope with agricultural NPS pollution. PMID:27441855

  6. The Investigation and Comparison of Furfural Removal from Wastewater using Cyclic Biological Reactor (CBR and Fusarium Culmorum Granules

    Directory of Open Access Journals (Sweden)

    Mostafa Leili

    2013-09-01

    Conclusion: Under different operating conditions of biological systems, high removal efficiency of furfural was observed, but CBR in comparison with Fusarium culmorum granules reached the optimum and desired removal efficiency in shorter time. Therefore, these systems can be developed and replaced with chemical methods to treat furfural containing wastewater.

  7. Physico-chemical factors affecting the E.coli removal in a rotating biological contactor (RBC) treating UASB effluent

    NARCIS (Netherlands)

    Tafwik, A.; Klapwijk, A.; Buuren, van J.C.L.; El-Gohary, F.; Lettinga, G.

    2004-01-01

    The removal mechanism of E coli from UASB effluent using a Rotating Biological Contractor (RBC) has been investigated. Preliminary batch experiments in a RBC indicate a first-order removal kinetics. Variation in the dissolved oxygen concentration and E coli counts over the depth of the RBC has been

  8. Decentralized two-stage sewage treatment by chemical-biological flocculation combined with microalgae biofilm for nutrient immobilization in a roof installed parallel plate reactor.

    Science.gov (United States)

    Zamalloa, Carlos; Boon, Nico; Verstraete, Willy

    2013-02-01

    In this lab-scale study, domestic wastewater is subjected to a chemical biological adsorption (A-stage), followed by treatment in an innovative roof installed parallel plate microalgae biofilm reactor for nutrient immobilization (I-stage). The A-stage process was operated at a hydraulic retention time (HRT) of 1h and a solid retention time of 1day (FeSO(4) as flocculant). The I-stage, which consequently received the effluent of the A-stage process, was operated at an HRT of 1day and exposed to natural light. The overall system removed on average 74% of the total chemical oxygen demand, 82% of the total suspended solids, 67% of the total nitrogen and 96% of the total phosphorous in the wastewater. The design involves a relatively low capital and operating cost which is in the order of 0.5€/m(3) wastewater treated. These aspects suggest that the A/I process can be used as a decentralized domestic wastewater treatment system.

  9. Calcium effect on the metabolic pathway of phosphorus accumulating organisms in enhanced biological phosphorus removal systems.

    Science.gov (United States)

    Zhang, Hai-Ling; Sheng, Guo-Ping; Fang, Wei; Wang, Yong-Peng; Fang, Cai-Yun; Shao, Li-Min; Yu, Han-Qing

    2015-11-01

    Phosphorus accumulating organisms (PAOs) have been found to act as glycogen-accumulating organisms (GAOs) under certain conditions, thus, the deterioration in the performance of enhanced biological phosphorus removal systems is not always attributed to the proliferation of GAOs. In this work, the effects of calcium on the metabolic pathway of PAOs were explored. It was found that when the influent Ca(2+) concentration was elevated, the tendency and extent of extracellular calcium phosphate precipitation increased, and the intracellular inert Ca-bound polyphosphate was synthesized, while the microbial population remained almost unchanged. The changes in the ratios of phosphorus released/acetate uptaken, the glycogen degraded/acetate uptaken and the poly-β-hydroxyalkanoates synthesized/acetate uptaken during the anaerobic period confirm that, as the influent Ca(2+) concentration was increased, the polyphosphate-accumulating metabolism was partially shifted to the glycogen-accumulating metabolism. At an influent Ca(2+) around 50 mg/L, in addition to the extracellular calcium phosphate precipitation, the intracellular inert Ca-bound polyphosphate synthesis might also be involved in the metabolic change of PAOs. The results of the present work would be beneficial to better understand the biochemical metabolism of PAOs in enhanced biological phosphorus removal systems. PMID:26233656

  10. Integration of photocatalysis and biological treatment for azo dye removal--application to AR183.

    Science.gov (United States)

    Chebli, Derradji; Fourcade, Florence; Brosillon, Stephan; Nacef, Saci; Amrane, Abdeltif

    2011-04-01

    The feasibility of coupling photocatalysis with biological treatment to treat effluents containing azo dyes was examined in this work. With this aim, the degradation of Acid Red 183 was investigated. The very low biodegradability of AR183 was confirmed beforehand by measuring the biological oxygen demand (BOD5). Photocatalysis experiments were carried out in a closed-loop step photoreactor. The reactor walls were covered by TiO2 catalyst coated on non-woven paper, and the effluent flowed over the photocatalyst as a thin falling film. The removal of the dye was 82.7% after 4 h, and a quasi-complete decolorization (98.5%) was obtained for 10 h of irradiation (initial concentration 100 mg L(-1)). The decrease in concentration followed pseudo-first-order kinetics, with a constant k of 0.47 h(-1). Mineralization and oxidation yields were 80% and 75%, respectively, after 10 h of pretreatment. Therefore, even if target compound oxidation occurs (COD removal), indicating a modification to the chemical structure, the concomitant high mineralization was not in favour of subsequent microbial growth. The BOD5 measurement confirmed the non-biodegradability of the irradiated solution, which remained toxic since the EC50 decreased from 35 to 3 mg L(-1). The proposed integrated process appeared, therefore, to be not relevant for the treatment of AR183. However, this result should be confirmed for other azo dyes.

  11. Biological sulphide removal from anaerobically treated domestic sewage: reactor performance and microbial community dynamics.

    Science.gov (United States)

    Garcia, Graziella Patrício Pereira; Diniz, Renata Côrtes Oliveira; Bicalho, Sarah Kinaip; Franco, Vitor Araujo de Souza; Gontijo, Eider Max de Oliveira; Toscano, Rodrigo Argolo; Canhestro, Kenia Oliveira; Santos, Merly Rita Dos; Carmo, Ana Luiza Rodrigues Dias; Lobato, Livia Cristina S; Brandt, Emanuel Manfred F; Chernicharo, Carlos A L; Calabria de Araujo, Juliana

    2015-01-01

    We developed a biological sulphide oxidation system and evaluated two reactors (shaped similar to the settler compartment of an up-flow anaerobic sludge blanket [UASB] reactor) with different support materials for biomass retention: polypropylene rings and polyurethane foam. The start-up reaction was achieved using microorganisms naturally occurring on the open surface of UASB reactors treating domestic wastewater. Sulphide removal efficiencies of 65% and 90% were achieved with hydraulic retention times (HRTs) of 24 and 12 h, respectively, in both reactors. However, a higher amount of elemental sulphur was formed and accumulated in the biomass from reactor 1 (20 mg S(0) g(-1) VTS) than in that from reactor 2 (2.9 mg S(0) g(-1) VTS) with an HRT of 24 h. Denaturing gradient gel electrophoresis (DGGE) results revealed that the the pink and green biomass that developed in both reactors comprised a diverse bacterial community and had sequences related to phototrophic green and purple-sulphur bacteria such as Chlorobium sp., Chloronema giganteum, and Chromatiaceae. DGGE band patterns also demonstrated that bacterial community was dynamic over time within the same reactor and that different support materials selected for distinct bacterial communities. Taken together, these results indicated that sulphide concentrations of 1-6 mg L(-1) could be efficiently removed from the effluent of a pilot-scale UASB reactor in two sulphide biological oxidation reactors at HRTs of 12 and 24 h, showing the potential for sulphur recovery from anaerobically treated domestic wastewater.

  12. Integration of photocatalysis and biological treatment for azo dye removal--application to AR183.

    Science.gov (United States)

    Chebli, Derradji; Fourcade, Florence; Brosillon, Stephan; Nacef, Saci; Amrane, Abdeltif

    2011-04-01

    The feasibility of coupling photocatalysis with biological treatment to treat effluents containing azo dyes was examined in this work. With this aim, the degradation of Acid Red 183 was investigated. The very low biodegradability of AR183 was confirmed beforehand by measuring the biological oxygen demand (BOD5). Photocatalysis experiments were carried out in a closed-loop step photoreactor. The reactor walls were covered by TiO2 catalyst coated on non-woven paper, and the effluent flowed over the photocatalyst as a thin falling film. The removal of the dye was 82.7% after 4 h, and a quasi-complete decolorization (98.5%) was obtained for 10 h of irradiation (initial concentration 100 mg L(-1)). The decrease in concentration followed pseudo-first-order kinetics, with a constant k of 0.47 h(-1). Mineralization and oxidation yields were 80% and 75%, respectively, after 10 h of pretreatment. Therefore, even if target compound oxidation occurs (COD removal), indicating a modification to the chemical structure, the concomitant high mineralization was not in favour of subsequent microbial growth. The BOD5 measurement confirmed the non-biodegradability of the irradiated solution, which remained toxic since the EC50 decreased from 35 to 3 mg L(-1). The proposed integrated process appeared, therefore, to be not relevant for the treatment of AR183. However, this result should be confirmed for other azo dyes. PMID:21877531

  13. Removal of dichloromethane from waste gases in a biological trickling filter. Doctoral thesis

    Energy Technology Data Exchange (ETDEWEB)

    Diks, R.M.M.

    1992-04-03

    Biological waste gas purification systems, especially biofilters, are increasingly applied in different branches of industry, not only for the elimination of odorous, easily biodegradable compounds, but also for the removal of toxic xenobiotics from waste gases. Although successful in most cases, a biofilter cannot be applied if large amounts of acidifying or inhibiting compounds accumulate in the filter material during the microbial degradation of the contaminants present in the waste gas. The thesis describes the development of a biological trickling filter, in which the above-mentioned problems can be easily dealt with. In this reactor the waste gas is forced to rise through a bed of inert packing material, on which a suitable microbial flora is immobilized. By the recirculation of a water phase through this system, acids produced are continuously removed from the filter bed and hence microbial activity is maintained. The flowing liquid phase also allows for the continuous neutralization and control of the optimal physiological conditions, i.e. temperature, pH and concentration of inhibiting compounds.

  14. Roles of extracellular polymeric substances in enhanced biological phosphorus removal process.

    Science.gov (United States)

    Li, Wen-Wei; Zhang, Hai-Ling; Sheng, Guo-Ping; Yu, Han-Qing

    2015-12-01

    Enhanced biological phosphorus removal (EBPR) process is known to mainly rely on the ability of phosphorus-accumulating organisms to take up, transform and store excess amount of phosphorus (P) inside the cells. However, recent studies have revealed considerable accumulation of P also in the extracellular polymeric substances (EPS) of sludge, implying a non-negligible role of EPS in P removal by EBPR sludge. However, the contribution of EPS to P uptake and the forms of accumulated extracellular P vary substantially in different studies, and the underlying mechanism of P transformation and transportation in EPS remains poorly understood. This review provides a new recognition into the P removal process in EBPR system by incorporating the role of EPS. It overviews on the characteristics of P accumulation in EPS, explores the mechanism of P transformation and transportation in EBPR sludge and EPS, summarizes the main influential factors for the P-accumulation properties of EPS, and discusses the remaining knowledge gaps and needed future efforts that may lead to better understanding and use of such an EPS role for maximizing P recovery from wastewater. PMID:26143588

  15. Biological sulfate removal from construction and demolition debris leachate: effect of bioreactor configuration.

    Science.gov (United States)

    Kijjanapanich, Pimluck; Do, Anh Tien; Annachhatre, Ajit P; Esposito, Giovanni; Yeh, Daniel H; Lens, Piet N L

    2014-03-30

    Due to the contamination of construction and demolition debris (CDD) by gypsum drywall, especially, its sand fraction (CDD sand, CDDS), the sulfate content in CDDS exceeds the posed limit of the maximum amount of sulfate present in building sand (1.73 g sulfate per kg of sand for the Netherlands). Therefore, the CDDS cannot be reused for construction. The CDDS has to be washed in order to remove most of the impurities and to obtain the right sulfate content, thus generating a leachate, containing high sulfate and calcium concentrations. This study aimed at developing a biological sulfate reduction system for CDDS leachate treatment and compared three different reactor configurations for the sulfate reduction step: the upflow anaerobic sludge blanket (UASB) reactor, inverse fluidized bed (IFB) reactor and gas lift anaerobic membrane bioreactor (GL-AnMBR). This investigation demonstrated that all three systems can be applied for the treatment of CDDS leachate. The highest sulfate removal efficiency of 75-85% was achieved at a hydraulic retention time (HRT) of 15.5h. A high calcium concentration up to 1,000 mg L(-1) did not give any adverse effect on the sulfate removal efficiency of the IFB and GL-AnMBR systems. PMID:24211179

  16. Cultivation of Chlorella sp. using raw dairy wastewater for nutrient removal and biodiesel production: Characteristics comparison of indoor bench-scale and outdoor pilot-scale cultures.

    Science.gov (United States)

    Lu, Weidong; Wang, Zhongming; Wang, Xuewei; Yuan, Zhenhong

    2015-09-01

    The biomass productivity and nutrient removal capacity of simultaneous Chlorella sp. cultivation for biodiesel production and nutrient removal in raw dairy wastewater (RDW) in indoor bench-scale and outdoor pilot-scale photobioreactors were compared. Results from the current work show that maximum biomass productivity in indoor bench-scale cultures can reach 260 mg L(-1) day(-1), compared to that of 110 mg L(-1) day(-1) in outdoor pilot-scale cultures. Maximum chemical oxygen demand (COD), total nitrogen (TN), and total phosphorous (TP) removal rate obtained in indoor conditions was 88.38, 38.34, and 2.03 mg L(-1) day(-1), respectively, this compared to 41.31, 6.58, and 2.74 mg L(-1) day(-1), respectively, for outdoor conditions. Finally, dominant fatty acids determined to be C16/C18 in outdoor pilot-scale cultures indicated great potential for scale up of Chlorella sp. cultivation in RDW for high quality biodiesel production coupling with RDW treatment.

  17. Impact of hazardous events on the removal of nutrients and trace organic contaminants by an anoxic-aerobic membrane bioreactor receiving real wastewater.

    Science.gov (United States)

    Phan, Hop V; Hai, Faisal I; McDonald, James A; Khan, Stuart J; van de Merwe, Jason P; Leusch, Frederic D L; Zhang, Ren; Price, William E; Broeckmann, Andreas; Nghiem, Long D

    2015-09-01

    The impacts of four simulated hazardous events, namely, aeration failure, power loss, and chemical shocks (ammonia or bleach) on the performance of an anoxic-aerobic membrane bioreactor (MBR) receiving real wastewater were investigated. Hazardous events could alter pH and/or oxidation reduction potential of the mixed liquor and inhibit biomass growth, thus affecting the removal of bulk organics, nutrients and trace organic contaminants (TrOC). Chemical shocks generally exerted greater impact on MBR performance than aeration/power failure events, with ammonia shock exerting the greatest impact. Compared to total organic carbon, nutrient removal was more severely affected. Removal of the hydrophilic TrOCs that are resistant and/or occur at high concentrations in wastewater was notably affected. The MBR effectively reduced estrogenicity and toxicity from wastewater, but chemical shocks could temporarily increase the endocrine activity of the effluent. Depending on the chemical shock-dose and the membrane flux, hazardous events can exacerbate membrane fouling. PMID:26038323

  18. Biological Phosphorus Removal During High-Rate, Low-Temperature, Anaerobic Digestion of Wastewater.

    Science.gov (United States)

    Keating, Ciara; Chin, Jason P; Hughes, Dermot; Manesiotis, Panagiotis; Cysneiros, Denise; Mahony, Therese; Smith, Cindy J; McGrath, John W; O'Flaherty, Vincent

    2016-01-01

    We report, for the first time, extensive biologically mediated phosphate removal from wastewater during high-rate anaerobic digestion (AD). A hybrid sludge bed/fixed-film (packed pumice stone) reactor was employed for low-temperature (12°C) anaerobic treatment of synthetic sewage wastewater. Successful phosphate removal from the wastewater (up to 78% of influent phosphate) was observed, mediated by biofilms in the reactor. Scanning electron microscopy and energy dispersive X-ray analysis revealed the accumulation of elemental phosphorus (∼2%) within the sludge bed and fixed-film biofilms. 4', 6-diamidino-2-phenylindole (DAPI) staining indicated phosphorus accumulation was biological in nature and mediated through the formation of intracellular inorganic polyphosphate (polyP) granules within these biofilms. DAPI staining further indicated that polyP accumulation was rarely associated with free cells. Efficient and consistent chemical oxygen demand (COD) removal was recorded, throughout the 732-day trial, at applied organic loading rates between 0.4 and 1.5 kg COD m(-3) d(-1) and hydraulic retention times of 8-24 h, while phosphate removal efficiency ranged from 28 to 78% on average per phase. Analysis of protein hydrolysis kinetics and the methanogenic activity profiles of the biomass revealed the development, at 12°C, of active hydrolytic and methanogenic populations. Temporal microbial changes were monitored using Illumina MiSeq analysis of bacterial and archaeal 16S rRNA gene sequences. The dominant bacterial phyla present in the biomass at the conclusion of the trial were the Proteobacteria and Firmicutes and the dominant archaeal genus was Methanosaeta. Trichococcus and Flavobacterium populations, previously associated with low temperature protein degradation, developed in the reactor biomass. The presence of previously characterized polyphosphate accumulating organisms (PAOs) such as Rhodocyclus, Chromatiales, Actinobacter, and Acinetobacter was recorded

  19. Biological phosphorus removal during high-rate, low-temperature, anaerobic digestion of wastewater

    Directory of Open Access Journals (Sweden)

    Ciara eKeating

    2016-03-01

    Full Text Available We report, for the first time, extensive biologically-mediated phosphate removal from wastewater during high-rate anaerobic digestion (AD. A hybrid sludge bed/fixed-film (packed pumice stone reactor was employed for low-temperature (12°C anaerobic treatment of synthetic sewage wastewater. Successful phosphate removal from the wastewater (up to 78% of influent phosphate was observed, mediated by biofilms in the reactor. Scanning electron microscopy and energy dispersive X-ray analysis revealed the accumulation of elemental phosphorus (~2% within the sludge bed and fixed-film biofilms. 4’, 6-diamidino-2-phenylindole (DAPI staining indicated phosphorus accumulation was biological in nature and mediated through the formation of intracellular inorganic polyphosphate (polyP granules within these biofilms. DAPI staining further indicated that polyP accumulation was rarely associated with free cells. Efficient and consistent chemical oxygen demand (COD removal was recorded, throughout the 732-day trial, at applied organic loading rates between 0.4-1.5 kg COD m-3 d-1 and hydraulic retention times of 8-24 hours, while phosphate removal efficiency ranged from 28-78% on average per phase. Analysis of protein hydrolysis kinetics and the methanogenic activity profiles of the biomass revealed the development, at 12˚C, of active hydrolytic and methanogenic populations. Temporal microbial changes were monitored using Illumina Miseq analysis of bacterial and archaeal 16S rRNA gene sequences. The dominant bacterial phyla present in the biomass at the conclusion of the trial were the Proteobacteria and Firmicutes and the dominant archaeal genus was Methanosaeta. Trichococcus and Flavobacterium populations, previously associated with low temperature protein degradation, developed in the reactor biomass. The presence of previously characterised polyphosphate accumulating organisms (PAOs such as Rhodocyclus, Chromatiales, Actinobacter and Acinetobacter was

  20. Kinetic analysis of anaerobic phosphorus release during biological phosphorus removal process

    Institute of Scientific and Technical Information of China (English)

    DOU Junfeng; LUO Guyuan; LIU Xiang

    2007-01-01

    Enhanced biological phosphorus removal(EBPR)is a commonly used and sustainable method for phosphorus removal from wastewater.Poly-β-hydroxybutyrate(PHB),polyphosphate,and glycogen are three kinds of intracellular storage polymers in phosphorus accumulation organisms.The variation of these polymers under different conditions has an apparent influence on anaerobic phosphorus release,which is very important for controlling the performance of EBPR.To obtain the mechanism and kinetic character of anaerobic phosphorus release,a series of batch experiments were performed using the excessively aerated sludge from the aerobic unit of the biological phosphorus removal system in this study.The results showed that the volatile suspended solid(vss)had an increasing trend,while the mixed liquid suspended sludge(MLSS)and ashes were reduced during the anaerobic phosphorus release process.The interruption of anaerobic HAc-uptake and phosphorus-release occurs when the glycogen in the phosphorus-accumulating-organisms is exhausted.Under the condition of lower initial HAc-COD,HAc became the limiting factor after some time for anaerobic HAc uptake.Under the condition of higher initial HAc-COD,HAc uptake was stopped because of the depletion of glycogen in the microorganisms.The mean ratio of △ρP/△ρPHB,△ρGLY/△ρPHB,△ρP/△COD,and △ρPHB/△COD was 0.48,0.50,0.44.and 0.92.respectively,which was nearly the same as the theoretical value.The calibrated kinetic parameters of the HAc-uptake and phosphorus-release model were evaluated as Kgly was 0.005,and KCOD was 3 mg/L.An apparently linear correlation was observed between the ratio of △ρP/△COD and pH of the solution,and the equation between them was obtained in this study.

  1. Is biological treatment a viable alternative for micropollutant removal in drinking water treatment processes?

    Science.gov (United States)

    Benner, Jessica; Helbling, Damian E; Kohler, Hans-Peter E; Wittebol, Janneke; Kaiser, Elena; Prasse, Carsten; Ternes, Thomas A; Albers, Christian N; Aamand, Jens; Horemans, Benjamin; Springael, Dirk; Walravens, Eddy; Boon, Nico

    2013-10-15

    In western societies, clean and safe drinking water is often taken for granted, but there are threats to drinking water resources that should not be underestimated. Contamination of drinking water sources by anthropogenic chemicals is one threat that is particularly widespread in industrialized nations. Recently, a significant amount of attention has been given to the occurrence of micropollutants in the urban water cycle. Micropollutants are bioactive and/or persistent chemicals originating from diverse sources that are frequently detected in water resources in the pg/L to μg/L range. The aim of this review is to critically evaluate the viability of biological treatment processes as a means to remove micropollutants from drinking water resources. We first place the micropollutant problem in context by providing a comprehensive summary of the reported occurrence of micropollutants in raw water used directly for drinking water production and in finished drinking water. We then present a critical discussion on conventional and advanced drinking water treatment processes and their contribution to micropollutant removal. Finally, we propose biological treatment and bioaugmentation as a potential targeted, cost-effective, and sustainable alternative to existing processes while critically examining the technical limitations and scientific challenges that need to be addressed prior to implementation. This review will serve as a valuable source of data and literature for water utilities, water researchers, policy makers, and environmental consultants. Meanwhile this review will open the door to meaningful discussion on the feasibility and application of biological treatment and bioaugmentation in drinking water treatment processes to protect the public from exposure to micropollutants. PMID:24053940

  2. Exportação de nutrientes nos tubérculos de batata em função de doses de sulfato de potássio Nutrient removal by potato tubers in response to potassium sulphate applications

    Directory of Open Access Journals (Sweden)

    Roberto Anjos Reis Júnior

    2001-11-01

    Full Text Available A batata, importante olerícola no Brasil e no mundo, recebe altas doses de fertilizantes, especialmente potássicos. Dentre estes, o sulfato de potássio destaca-se devido ao conceito de que sua utilização melhora a qualidade dos tubérculos. Os fertilizantes representam um significativo percentual dos custos de produção desta cultura. Logo, o uso eficiente dos adubos deve ser alcançado para garantir competitividade do bataticultor no mercado. A avaliação das quantidades de nutrientes extraídas e exportadas pelos tubérculos durante o ciclo de desenvolvimento é uma ferramenta útil para otimizar o uso de fertilizantes. Para avaliar a extração e exportação de nutrientes nos tubérculos de batata, em função de doses de sulfato de potássio, foram aplicados 0; 125; 250; 500; 1000 e 2000 kg ha-1 de K2SO4 no sulco de plantio, em Viçosa (MG. Para avaliar os teores e as exportações de N, P, K, Ca, Mg, S, Cl, Mn e Zn nos tubérculos, duas plantas/parcela foram amostradas aos 20 dias após a emergência das plantas (DAE, aos 48 DAE e na colheita. O experimento foi analisado como fatorial 6x3, com seis doses de K2SO4 e três épocas de amostragem, delineado em blocos ao acaso, com quatro repetições. A adubação com sulfato de potássio promoveu acréscimos nos teores de Cl, Mn e Zn nos tubérculos. As exportações de K, Ca, Mg, S, Mn e Cl aumentaram em resposta às doses de sulfato de potássio, somente na colheita. Na máxima produtividade de tubérculos (30,5 Mg ha-1, com 736 kg ha-1 de K2SO4, foram estimadas as seguintes exportações, em kg ha-1: N (99,1; P (14,2; K (118,5; Ca (2,10; Mg (6,50; S (9,28; Cl (8,18; Mn (0,048 e Zn (0,102. A exportação de nutrientes nos tubérculos representa importante perda de nutrientes do solo e sua avaliação, a princípio, deve ser utilizada para calibrar a recomendação de fertilizantes.Removal of nutrients by potato tubers was evaluated in response to the application of potassium sulphate

  3. Effect of Slash Burning on Nutrient Removal and Soil Fertility in Chinese Fir and Evergreen Broadleaved Forests of Mid-Subtropical China

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A Chinese fir forest (Cunninghamia lanceolata, CF) and an evergreen broadleaved forest (EB) located inFujian Province, southeastern China, were examined following slash burning to compare nutrient capital andtopsoil properties with pre-burn levels. After fire, nutrient (N, P and K) removal from burning residues wasestimated at 302.5 kg ha-1 in the CF and 644.8 kg ha-1 in the EB. Fire reduced the topsoil capitals of totalN and P by about 20% and 10%, respectively, in both forests, while K capital was increased in the topsoils ofboth forests following fire. Total site nutrient loss through surface erosion was 28.4 kg (N) ha-1, 8.4 kg (P)ha-1 and 328.7 kg (K) ha-1 in the CF. In the EB, the losses of total N, P and K were 58.5, 10.5 and 396.3kg ha-1, respectively. Improvement of soil structure and increase in mineralization of nutrients associatedwith increased microbe number and enzyme activities and elevated soil respiration occurred 5 days after fire.However, organic matter and available nutrient contents and most of other soil parameters declined one yearafter fire on the burned CF and EB topsoils. These results suggest that short-term site productivity canbe stimulated immediately, but reduced subsequently by soil and water losses, especially in South China,where high-intensity precipitation, steep slopes and fragile soil can be expected. Therefore, the silviculturalmeasurements should be developed in plantation management.

  4. Occurrence of cyclophosphamide and ifosfamide in aqueous environment and their removal by biological and abiotic wastewater treatment processes.

    Science.gov (United States)

    Česen, Marjeta; Kosjek, Tina; Laimou-Geraniou, Maria; Kompare, Boris; Širok, Brane; Lambropolou, Dimitra; Heath, Ester

    2015-09-15

    Cytostatic drug residues in the aqueous environment are of concern due to their possible adverse effects on non-target organisms. Here we report the occurrence and removal efficiency of cyclophosphamide (CP) and ifosfamide (IF) by biological and abiotic treatments including advanced oxidation processes (AOPs). Cyclophosphamide was detected in hospital wastewaters (14-22,000 ng L(-1)), wastewater treatment plant influents (19-27 ng L(-1)) and effluent (17 ng L(-1)), whereas IF was detected only in hospital wastewaters (48-6800 ng L(-1)). The highest removal efficiency during biological treatment (attached growth biomass in a flow through bioreactor) was 59 ± 15% and 35 ± 9.3% for CP and IF, respectively. Also reported are the removal efficiencies of both compounds from wastewater using hydrodynamic cavitation (HC), ozonation (O3) and/or UV, either individually or in combination with hydrogen peroxide (H2O2). Hydrodynamic cavitation did not remove CP and IF to any significant degree. The highest removal efficiencies: 99 ± 0.71% for CP and 94 ± 2.4% for IF, were achieved using UV/O3/H2O2 at 5 g L(-1) for 120 min. When combined with biological treatment, removal efficiencies were >99% for both compounds. This is the first report of combined biological and AOP treatment of CP and IF from wastewater with a removal efficiency >99%.

  5. Colour and organic removal of biologically treated coffee curing wastewater by electrochemical oxidation method

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The treatment of biologically treated wastewater of coffee-curing industry by the electrochemical oxidation using steel anode were investigated. Bench-scale experiments were conducted for activated sludge process on raw wastewater and the treated effluents were further treated by electrochemical oxidation method for its color and organic content removal. The efficiency of the process was determined in terms of removal percentage of COD, BOD and color during the course of reaction. Several operating parameters like time, pH and current density were examined to ascertain their effects on the treatment efficiency. Steel anode was found to be effective for the COD and color removal with anode efficiency of 0.118 kgCOD-1A-1m-2 and energy consumption 20.61 kWh.kg-1 of COD at pH 9. The decrease in pH from 9 to 3 found to increase the anode efficiency from 0.118 kgCOD-1A-1m-2 to 0.144 kWh.kg-1 of COD while decrease the energy consumption from 20.61 kWh.kg-1 of COD to12 .86 kWh.kg-1 of COD. The pH of 5 was considered an ideal from the present treatment process as it avoids the addition of chemicals for neutralization of treated effluents and also economical with respect to energy consumption. An empirical relation developed for relationship between applied current density and COD removal efficiency showed strong predictive capability with coefficient of determination of 96.5%.

  6. Colour and organic removal of biologically treated coffee curing wastewater by electrochemical oxidation method.

    Science.gov (United States)

    Bejankiwar, Rajesh S; Lokesh, K S; Gowda, T P Halappa

    2003-05-01

    The treatment of biologically treated wastewater of coffee-curing industry by the electrochemical oxidation using steel anode was investigated. Bench-scale experiments were conducted for activated sludge process on raw wastewater and the treated effluents were further treated by electrochemical oxidation method for its colour and organic content removal. The efficiency of the process was determined in terms of removal percentage of COD, BOD and colour during the course of reaction. Several operating parameters like time, pH and current density were examined to ascertain their effects on the treatment efficiency. Steel anode was found to be effective for the COD and colour removal with anode efficiency of 0.118 kgCOD x h(-1) x A(-1) x m(-2) and energy consumption 20.61 kWh x kg(-1) of COD at pH 9. The decrease in pH from 9 to 3 found to increase the anode efficiency from 0.118 kgCOD x h(-1) x A(-1) x m(-2) to 0.144 kWh x kg(-1) of COD while decrease the energy consumption from 20.61 kWh x kg(-1) of COD to 12.86 kWh x kg(-1) of COD. The pH of 5 was considered an ideal from the present treatment process as it avoids the addition of chemicals for neutralization of treated effluents and also economical with respect to energy consumption. An empirical relation developed for relationship between applied current density and COD removal efficiency showed strong predictive capability with coefficient of determination of 96.5%. PMID:12938980

  7. Enhanced Removal of Lead by Chemically and Biologically Treated Carbonaceous Materials

    Directory of Open Access Journals (Sweden)

    Mohamed E. Mahmoud

    2012-01-01

    Full Text Available Hybrid sorbents and biosorbents were synthesized via chemical and biological treatment of active carbon by simple and direct redox reaction followed by surface loading of baker’s yeast. Surface functionality and morphology of chemically and biologically modified sorbents and biosorbents were studied by Fourier Transform Infrared analysis and scanning electron microscope imaging. Hybrid carbonaceous sorbents and biosorbents were characterized by excellent efficiency and superiority toward lead(II sorption compared to blank active carbon providing a maximum sorption capacity of lead(II ion as 500 μmol g−1. Sorption processes of lead(II by these hybrid materials were investigated under the influence of several controlling parameters such as pH, contact time, mass of sorbent and biosorbent, lead(II concentration, and foreign ions. Lead(II sorption mechanisms were found to obey the Langmuir and BET isotherm models. The potential applications of chemically and biologically modified-active carbonaceous materials for removal and extraction of lead from real water matrices were also studied via a double-stage microcolumn technique. The results of this study were found to denote to superior recovery values of lead (95.0–99.0±3.0–5.0% by various carbonaceous-modified-bakers yeast biosorbents.

  8. Effective Biological Nitrogen Removal Treatment Processes for Domestic Wastewaters with Low C/N Ratios: A Review

    DEFF Research Database (Denmark)

    Sun, Sheng-Peng; Pellicer i Nàcher, Carles; Merkey, Brian;

    2010-01-01

    Discharge of nitrogenous components to water bodies can cause eutrophication, deterioration of water quality, toxicity to aquatic life, and pose a potential hazard to human and animal health. Biological nitrogen removal can remove nitrogenous components via conversion to harmless nitrogen gas...... with high efficiency and relative low costs. However, the removal of nitrogen from domestic wastewater with a low carbon/nitrogen (C/N) ratio can often be limited in municipal wastewater plants (WWTPs) because organic carbon is a limiting factor for denitrification. The present work reviews innovative....... They can effectively be used for nitrogen removal from low C/N domestic wastewater without external carbon addition. In addition, conventional and alternative carbon sources for enhanced biological nitrogen removal were also reviewed. We conclude that alternative carbon sources such as wine distillery...

  9. Instability of biological nitrogen removal in a cokes wastewater treatment facility during summer

    International Nuclear Information System (INIS)

    Failure in nitrogen removal of cokes wastewater occurs occasionally during summer season (38 deg. C) due to the instability of nitrification process. The objective of this study was to examine why the nitrification process is unstable especially in summer. Various parameters such as pH, temperature, nutrients and pollutants were examined in batch experiments using activated sludge and wastewater obtained from a full-scale cokes wastewater treatment facility. Batch experiments showed that nitrification rate of the activated sludge was faster in summer (38 deg. C) than in spring or autumn (29 deg. C) and the toxic effects of cyanide, phenol and thiocyanate on nitrification were reduced with increasing temperature. Meanwhile, experiment using continuous reactor showed that the reduction rate in nitrification efficiency was higher at 38 deg. C than at 29 deg. C. In conclusion, the instability of full-scale nitrification process in summer might be mainly due to washing out of nitrifiers by fast growth of competitive microorganisms at higher temperature under increased concentrations of phenol and thiocyanate

  10. Effect of amended soil and hydraulic load on enhanced biological nitrogen removal in lab-scale SWIS.

    Science.gov (United States)

    Zou, J L; Dai, Y; Sun, T H; Li, Y H; Li, G B; Li, Q Y

    2009-04-30

    To characterize the effect of amended soil on nitrogen removal in subsurface wastewater infiltration system (SWIS), culture, grass carbon, and zeolite were mixed to produce microbial inoculums, and then the optimal microbial inoculums, nutrient substance, cinder, and original soil were mixed to produce the soils through bioaugmentation. Results indicate that the microbial inoculums (culture+50% grass carbon+50% zeolite) and the amended soil (12.5% microbial inoculums+25% nutrient substrate+12.5% cinder+50% original soil) have the optimal biogenic stimulating properties, and the adsorption capacity of the amended soil are 1.216 mg-Pg(-1) and 0.495 mg-Ng(-1). The laboratory soil column experiment indicates that the efficient mode of nitrogen removal in lab-scale SWIS is adsorption-nitrification-denitrification and the nitrification/denitrification can be enhanced by the application of the amended soil. On average, the SWIS filled with amended soil converts 85% of ammonia nitrogen (NH(4)(+)-N) to NO(x)(-)-N and removes 49.8-60.6% of total nitrogen (TN), while the system filled with original soil removes 80% of NH(4)(+)-N and 31.3-43.2% of TN at 4-8 cm day(-1). Two systems are overloads at 10 cm day(-1). It is concluded that the microbial activities and nitrogen removal efficiencies are improved in SWIS after bioaugmentation.

  11. Effects of interspecific competition on the growth of macrophytes and nutrient removal in constructed wetlands: A comparative assessment of free water surface and horizontal subsurface flow systems.

    Science.gov (United States)

    Zheng, Yucong; Wang, Xiaochang; Dzakpasu, Mawuli; Zhao, Yaqian; Ngo, Huu Hao; Guo, Wenshan; Ge, Yuan; Xiong, Jiaqing

    2016-05-01

    The outcome of competition between adjoining interspecific colonies of Phragmites and Typha in two large field pilot-scale free water surface (FWS) and subsurface flow (SSF) CWs is evaluated. According to findings, the effect of interspecific competition was notable for Phragmites australis, whereby it showed the highest growth performance in both FWS and SSF wetland. In a mixed-culture, P. australis demonstrates superiority in terms of competitive interactions for space between plants. Furthermore, the interspecific competition among planted species seemed to cause different ecological responses of plant species in the two CWs. For example, while relatively high density and shoot height determined the high aboveground dry weight of P. australis in the FWS wetland, this association was not evident in the SSF. Additionally, while plants nutrients uptake accounts for a higher proportion of the nitrogen removal in FWS, that in the SSF accounts for a higher proportion of the phosphorous removal. PMID:26874442

  12. Biofilm establishment and heavy metal removal capacity of an indigenous mining algal-microbial consortium in a photo-rotating biological contactor.

    Science.gov (United States)

    Orandi, S; Lewis, D M; Moheimani, N R

    2012-09-01

    An indigenous mining algal-microbial consortium was immobilised within a laboratory-scale photo-rotating biological contactor (PRBC) that was used to investigate the potential for heavy metal removal from acid mine drainage (AMD). The microbial consortium, dominated by Ulothrix sp., was collected from the AMD at the Sar Cheshmeh copper mine in Iran. This paper discusses the parameters required to establish an algal-microbial biofilm used for heavy metal removal, including nutrient requirements and rotational speed. The PRBC was tested using synthesised AMD with the multi-ion and acidic composition of wastewater (containing 18 elements, and with a pH of 3.5 ± 0.5), from which the microbial consortium was collected. The biofilm was successfully developed on the PRBC's disc consortium over 60 days of batch-mode operation. The PRBC was then run continuously with a 24 h hydraulic residence time (HRT) over a ten-week period. Water analysis, performed on a weekly basis, demonstrated the ability of the algal-microbial biofilm to remove 20-50 % of the various metals in the order Cu > Ni > Mn > Zn > Sb > Se > Co > Al. These results clearly indicate the significant potential for indigenous AMD microorganisms to be exploited within a PRBC for AMD treatment.

  13. The Metal And Sulphate Removal From Mine Drainage Waters By Biological-Chemical Ways

    Directory of Open Access Journals (Sweden)

    Jenčárová Jana

    2015-06-01

    Full Text Available Mine drainage waters are often characterized by high concentrations of sulphates and metals as a consequence of the mining industry of sulphide minerals. The aims of this work are to prove some biological-chemical processes utilization for the mine drainage water treatment. The studied principles of contamination elimination from these waters include sulphate reduction and metal bioprecipitation by the application of sulphate-reducing bacteria (SRB. Other studied process was metal sorption by prepared biogenic sorbent. Mine drainage waters from Slovak localities Banská Štiavnica and Smolník were used to the pollution removal examination. In Banská Štiavnica water, sulphates decreased below the legislative limit. The elimination of zinc by sorption experiments achieved 84 % and 65 %, respectively.

  14. Dynamics of Intracellular Polymers in Enhanced Biological Phosphorus Removal Processes under Different Organic Carbon Concentrations

    Directory of Open Access Journals (Sweden)

    Lizhen Xing

    2013-01-01

    Full Text Available Enhanced biological phosphorus removal (EBPR may deteriorate or fail during low organic carbon loading periods. Polyphosphate accumulating organisms (PAOs in EBPR were acclimated under both high and low organic carbon conditions, and then dynamics of polymers in typical cycles, anaerobic conditions with excess organic carbons, and endogenous respiration conditions were examined. After long-term acclimation, it was found that organic loading rates did not affect the yield of PAOs and the applied low organic carbon concentrations were advantageous for the enrichment of PAOs. A low influent organic carbon concentration induced a high production of extracellular carbohydrate. During both anaerobic and aerobic endogenous respirations, when glycogen decreased to around 80 ± 10 mg C per gram of volatile suspended solids, PAOs began to utilize polyphosphate significantly. Regressed by the first-order reaction model, glycogen possessed the highest degradation rate and then was followed by polyphosphate, while biomass decay had the lowest degradation rate.

  15. Effects of Eichhornia crassipes and Ceratophyllum demersum on Soil and Water Environments and Nutrient Removal in Wetland Microcosms.

    Science.gov (United States)

    Sung, Kijune; Lee, Geun-Joo; Munster, Clyde

    2015-01-01

    Wetland plants are important components that influence the biogeochemistry of wetland ecosystems. Therefore, remediation performance in wetlands can differ depending on the growth forms of plants. In this study, the effects of Eichhornia crassipes (floating plant) and Ceratophyllum demersum (submerged plant) on the wetland soil and water environments were investigated using a microcosm study with simulated hydrology of retention-type wetlands between rainfall events. The C. demersum microcosm (SP) showed the fastest recovery with a diel fluctuation pattern of dissolved oxygen, pH, and oxidation-reduction potential (ORP) from the impacts of nutrient inflow. Moreover, SP exhibited the lowest decrease in sediment ORP, the highest dehydrogenase activity, and more organic forms of nitrogen and phosphorus. E. crassipes microcosms exhibited the lowest water temperature, and efficiently controlled algae. In the presence of plants, the total nitrogen and phosphorus concentrations in water rapidly decreased, and the composition of organic and inorganic nutrient forms was altered along with a decrease in concentration. The results indicate that wetland plants help retain nutrients in the system, but the effects varied based on the wetland plant growth forms. PMID:25581097

  16. Soil properties and biological activity as influenced by nutrient management in rice- fallow sorghum

    Directory of Open Access Journals (Sweden)

    N Goutami

    2015-06-01

    Full Text Available A field experiment was conducted to observe the effect of inorganics, bio-fertilizers and FYM applied to rice-fallow sorghum on soil properties and biological activity at Agricultural College Farm, Bapatla during 2012. Soil samples were collected at flowering and harvest of the crop and were analysed for bulk density (BD, porosity, pH, electrical conductivity (EC, organic carbon, N, P, K and micronutrients by standard methods. Results indicated that the soil properties viz., bulk density, porosity, pH and EC were not markedly influenced by the imposed treatments, while significantly high organic carbon was recorded in FYM treated plots. There was a significant influence of the treatments on available nitrogen and phosphorus, but not on potassium. Among micronutrients (Cu, Zn, Mn and Fe, the treatmental influence was significantly related to Fe only. Addition of inorganics in combination with organics and bio-fertilizers proved to be more efficient in improving the microbial population and enzyme activities (urease and dehydrogenase significantly.

  17. Removing constraints on the biomass production of freshwater macroalgae by manipulating water exchange to manage nutrient flux.

    Directory of Open Access Journals (Sweden)

    Andrew J Cole

    Full Text Available Freshwater macroalgae represent a largely overlooked group of phototrophic organisms that could play an important role within an industrial ecology context in both utilising waste nutrients and water and supplying biomass for animal feeds and renewable chemicals and fuels. This study used water from the intensive aquaculture of freshwater fish (Barramundi to examine how the biomass production rate and protein content of the freshwater macroalga Oedogonium responds to increasing the flux of nutrients and carbon, by either increasing water exchange rates or through the addition of supplementary nitrogen and CO2. Biomass production rates were highest at low flow rates (0.1-1 vol.day-1 using raw pond water. The addition of CO2 to cultures increased biomass production rates by between 2 and 25% with this effect strongest at low water exchange rates. Paradoxically, the addition of nitrogen to cultures decreased productivity, especially at low water exchange rates. The optimal culture of Oedogonium occurred at flow rates of between 0.5-1 vol.day-1, where uptake rates peaked at 1.09 g.m-2.day-1 for nitrogen and 0.13 g.m-2.day-1 for phosphorous. At these flow rates Oedogonium biomass had uptake efficiencies of 75.2% for nitrogen and 22.1% for phosphorous. In this study a nitrogen flux of 1.45 g.m-2.day-1 and a phosphorous flux of 0.6 g.m-2.day-1 was the minimum required to maintain the growth of Oedogonium at 16-17 g DW.m-2.day-1 and a crude protein content of 25%. A simple model of minimum inputs shows that for every gram of dry weight biomass production (g DW.m-2.day-1, Oedogonium requires 0.09 g.m-2.day-1 of nitrogen and 0.04 g.m-2.day-1 of phosphorous to maintain growth without nutrient limitation whilst simultaneously maintaining a high-nutrient uptake rate and efficiency. As such the integrated culture of freshwater macroalgae with aquaculture for the purposes of nutrient recovery is a feasible solution for the bioremediation of wastewater and the

  18. Intensifying enhanced biological phosphorus removal by calciumdolomitehydrate; Intensivierung der vermehrten biologischen Phosphatelimination durch Dolomitkalkhydrat

    Energy Technology Data Exchange (ETDEWEB)

    Soelter, M. [AKDOLIT GmbH, Wuelfrath (Germany)

    1999-02-01

    Utilization of enhanced biological phosphorus removal is increasingly considered an essential part in designing wastewater treatment plant due to ecological and economical advantages. Effects of Akdophos (=special dolime-hydrate) were investigated and monitored in operational tests at the industrial effluent clarification plant of Gerolsteiner Brunnen and the municipal plant Dremmen. Results of a full year cyclus demonstrate the efficiency of Akdophos in stabilizing and intensifying the enhanced Bio-P removal. Cost-analysis shows a considerable cost cutting potential regarding precipitants as well as improvement of sludge volume index with only low increase of excess sludge. Dry product dosage of Akdophos to the aeration tank has been proved a reliable and cost-effective process method. (orig.) [Deutsch] Oekokogische und oekonomische Vorteile bestaetigen zunehmend die Nutzung der erweiterten biologischen Phosphatelimination als wesentlichen Bestandteil der Konzeption von Abwasserreinigungsanlagen. Anhand grosstechnischer Versuche auf der Klaeranlage des Gerolsteiner Brunnen und auf der Klaeranlage Dremmen (Stadt Heinsberg) wurde die Wirkung von Akdorphos (=speziell hergestelltes Dolomitkalkhydrat) auf die biologischen Vorgaenge von Klaeranlagen untersucht. Im Betrieb ueber einen vollstaendigen Jahreszyklus konnte nachgewiesen werden, dass die biologische Phosphatelimination durch eine geringfuegige Dosierung von Akdophos intensiviert und stabilisiert wird. Die Kostenanalyse in beiden betrachteten Faellen zeigt neben einer Kostenreduktion bei den Faellmitteln weitere Einsparungen durch deutlich verbesserte Schlammabsetzeigenschaften bei sehr geringem Schlammehranfall. Die Dosierung von Akdophos erfolgt vorzugsweise trocken und unmittelbar in die Belebung. Die entsprechende Anlagentechnik hat sich als betriebssicher und kostenguenstig erwiesen. (orig.)

  19. Rare taxa have potential to make metabolic contributions in enhanced biological phosphorus removal ecosystems.

    Science.gov (United States)

    Lawson, Christopher E; Strachan, Blake J; Hanson, Niels W; Hahn, Aria S; Hall, Eric R; Rabinowitz, Barry; Mavinic, Donald S; Ramey, William D; Hallam, Steven J

    2015-12-01

    Enhanced biological phosphorus removal (EBPR) relies on diverse but specialized microbial communities to mediate the cycling and ultimate removal of phosphorus from municipal wastewaters. However, little is known about microbial activity and dynamics in relation to process fluctuations in EBPR ecosystems. Here, we monitored temporal changes in microbial community structure and potential activity across each bioreactor zone in a pilot-scale EBPR treatment plant by examining the ratio of small subunit ribosomal RNA (SSU rRNA) to SSU rRNA gene (rDNA) over a 120 day study period. Although the majority of operational taxonomic units (OTUs) in the EBPR ecosystem were rare, many maintained high potential activities based on SSU rRNA : rDNA ratios, suggesting that rare OTUs contribute substantially to protein synthesis potential in EBPR ecosystems. Few significant differences in OTU abundance and activity were observed between bioreactor redox zones, although differences in temporal activity were observed among phylogenetically cohesive OTUs. Moreover, observed temporal activity patterns could not be explained by measured process parameters, suggesting that other ecological drivers, such as grazing or viral lysis, modulated community interactions. Taken together, these results point towards complex interactions selected for within the EBPR ecosystem and highlight a previously unrecognized functional potential among low abundance microorganisms in engineered ecosystems. PMID:25857222

  20. Optimization of a full-scale Unitank wastewater treatment plant for biological phosphorus removal.

    Science.gov (United States)

    Zhou, Zhen; Xing, Can; Wu, Zhichao; Tong, Fei; Wang, Junru

    2014-01-01

    The Unitank process combines the advantages of traditional continuous-flow activated sludge processes and sequencing batch reactors, and has been extensively employed in many wastewater treatment plants (WWTPs) in China. Biological phosphorus removal (BPR) of a full-scale Unitank WWTP was optimized by increasing anaerobic time from 80 to 120 min in an operation cycle of 360 min and reducing solid retention time (SRT) from 21.3 to 13.1 d. The BPR efficiency of the full-scale Unitank system increased from 63.8% (SRT of 21.3 d) to 83.2% for a SRT of 13.1 d. When the anaerobic time increased from 80 to 120 min, the net anaerobic phosphorus release amount increased from 0.25 to 1.06 mg L(-1), and sludge phosphorus content rose from 13.8 to 15.0 mgP x (gSS)(-1). During half an operation cycle, the average specific phosphorus release rate increased from 0.097mgP x (gVSS x h)(-1) in 0-40 min to 0.825 mgP x (gVSS x h)(-1) in 40-60 min. Reducing SRT and increasing anaerobic time account for 84.6% and 15.4% in the total increment of phosphorus removal of 1.15 mgL(-1). PMID:24645458

  1. Metabolic versatility in full-scale wastewater treatment plants performing enhanced biological phosphorus removal.

    Science.gov (United States)

    Lanham, Ana B; Oehmen, Adrian; Saunders, Aaron M; Carvalho, Gilda; Nielsen, Per H; Reis, Maria A M

    2013-12-01

    This study analysed the enhanced biological phosphorus removal (EBPR) microbial community and metabolic performance of five full-scale EBPR systems by using fluorescence in situ hybridisation combined with off-line batch tests fed with acetate under anaerobic-aerobic conditions. The phosphorus accumulating organisms (PAOs) in all systems were stable and showed little variability between each plant, while glycogen accumulating organisms (GAOs) were present in two of the plants. The metabolic activity of each sludge showed the frequent involvement of the anaerobic tricarboxylic acid cycle (TCA) in PAO metabolism for the anaerobic generation of reducing equivalents, in addition to the more frequently reported glycolysis pathway. Metabolic variability in the use of the two pathways was also observed, between different systems and in the same system over time. The metabolic dynamics was linked to the availability of glycogen, where a higher utilisation of the glycolysis pathway was observed in the two systems employing side-stream hydrolysis, and the TCA cycle was more active in the A(2)O systems. Full-scale plants that showed higher glycolysis activity also exhibited superior P removal performance, suggesting that promotion of the glycolysis pathway over the TCA cycle could be beneficial towards the optimisation of EBPR systems.

  2. Advances in wastewater nitrogen removal by biological processes: state of the art review

    Directory of Open Access Journals (Sweden)

    Andrea G. Capodaglio

    2016-04-01

    Full Text Available The paper summarizes the state-of-the-art of the most recent advances in biological nitrogen removal, including process design criteria and technological innovations. With reference to the Modified Ludzck Ettinger (MLE process (pre-denitrification and nitrification in the activated sludge process, the most common nitrogen removal process used nowadays, a new design equation for the denitrification reactor based on specific denitrification rate (SDNR has been proposed. In addition, factors influencing SDNR (DO in the anoxic reactor; hydrodynamic behavior are analyzed, and technological solutions are proposed. Concerning technological advances, the paper presents a summary of various “deammonification” processes, better known by their patent names like ANAMMOX®, DEMON®, CANON®, ANITA® and others. These processes have already found applications in the treatment of high-strength wastewater such as digested sludge liquor and landfill leachate. Among other emerging denitrification technologies, consideration is given to the Membrane Biofilm Reactors (MBfRs that can be operated both in oxidation and reduction mode.

  3. Removal of nitrate and sulphate from biologically treated municipal wastewater by electrocoagulation

    Science.gov (United States)

    Sharma, Arun Kumar; Chopra, A. K.

    2015-07-01

    The present investigation observed the effect of current density (j), electrocoagulation (EC) time, inter electrode distance, electrode area, initial pH and settling time on the removal of nitrate (NO3 -) and sulphate (SO4 2-) from biologically treated municipal wastewater (BTMW), and optimization of the operating conditions of the EC process. A glass chamber of two-liter volume was used for the experiments with DC power supply using two electrode plates of aluminum (Al-Al). The maximum removal of NO3 - (63.21 %) and SO4 2- (79.98 %) of BTMW was found with the optimum operating conditions: current density: 2.65 A/m2, EC time: 40 min, inter electrode distance: 0.5 cm, electrode area: 160 cm2, initial pH: 7.5 and settling time: 60 min. The EC brought down the concentration of NO3 - within desirable limit of the Bureau of Indian Standard (BIS)/WHO for drinking water. Under optimal operating conditions, the operating cost was found to be 1.01/m3 of water in terms of the electrode consumption (23.71 × 10-5 kg Al/m3) and energy consumption (101.76 kWh/m3).

  4. Enhanced Biological Phosphorus Removal in SBR Using Glucose as a Single Organic Substrate

    Institute of Scientific and Technical Information of China (English)

    JIANG Yi-feng; LI Xiang-kun; FENG Xiao-yu; WANG Shu-tao; WANG Bao-zhen; LIU Ya-nan; CHEN Jian-meng

    2008-01-01

    Enhanced biological phosphorus removal (EBPR) was investigated in an anaerobic/aerobic sequencing batch reactor (SBR) supplied with glucose as a single organic substrate. The results illustrated that EBPR process could also occur successfully with glucose other than short chain fatty acids (SCFAs). High phosphorus release and polyhydroxyalkanoate (PHA) accumulation in the anaerobic phase was found vital for the removal of phosphorus during the aerobic phase. The measurement of intracellular reserves revealed that glycogen had a higher chance to replace the energy role of poly-P under anaerobic conditions. Moreover, glycogen was also utilized as the carbon source for PHA synthesis. as well as a reducing power as reported earlier. The accumulated PHA in this system was mainly in the form of poly-hydroxyvalerate (PHV) instead of polyhydroxybutyrate (PHB), and was inferred to be caused by the excess reducing power contained in glucose. Lactate as a fermentation product was also found released into the bulk solution. Applying fundamental biochemistry knowledge to the experimental results, a conceptual biochemical model was developed to explain the metabolism of the glucoseinduced EBPR.

  5. Exploring the Shift in Structure and Function of Microbial Communities Performing Biological Phosphorus Removal.

    Science.gov (United States)

    Mao, Yanping; Wang, Zhiping; Li, Liguan; Jiang, Xiaotao; Zhang, Xuxiang; Ren, Hongqiang; Zhang, Tong

    2016-01-01

    A sequencing batch reactor fed mainly by acetate was operated to perform enhanced biological phosphorus removal (EBPR). A short-term pH shock from 7.0 to 6.0 led to a complete loss of phosphate-removing capability and a drastic change of microbial communities. 16S rRNA gene pyrosequencing showed that large proportions of glycogen accumulating organisms (GAOs) (accounted for 16% of bacteria) bloomed, including Candidatus Competibacter phosphatis and Defluviicoccus-related tetrad-forming organism, causing deteriorated EBPR performance. The EBPR performance recovered with time and the dominant Candidatus Accumulibacter (Accumulibacter) clades shifted from Clade IIC to IIA while GAOs populations shrank significantly. The Accumulibacter population variation provided a good opportunity for genome binning using a bi-dimensional coverage method, and a genome of Accumulibacter Clade IIC was well retrieved with over 90% completeness. Comparative genomic analysis demonstrated that Accumulibacter clades had different abilities in nitrogen metabolism and carbon fixation, which shed light on enriching different Accumulibacter populations selectively. PMID:27547976

  6. Integrative microbial community analysis reveals full-scale enhanced biological phosphorus removal under tropical conditions

    Science.gov (United States)

    Law, Yingyu; Kirkegaard, Rasmus Hansen; Cokro, Angel Anisa; Liu, Xianghui; Arumugam, Krithika; Xie, Chao; Stokholm-Bjerregaard, Mikkel; Drautz-Moses, Daniela I.; Nielsen, Per Halkjær; Wuertz, Stefan; Williams, Rohan B. H.

    2016-05-01

    Management of phosphorus discharge from human waste is essential for the control of eutrophication in surface waters. Enhanced biological phosphorus removal (EBPR) is a sustainable, efficient way of removing phosphorus from waste water without employing chemical precipitation, but is assumed unachievable in tropical temperatures due to conditions that favour glycogen accumulating organisms (GAOs) over polyphosphate accumulating organisms (PAOs). Here, we show these assumptions are unfounded by studying comparative community dynamics in a full-scale plant following systematic perturbation of operational conditions, which modified community abundance, function and physicochemical state. A statistically significant increase in the relative abundance of the PAO Accumulibacter was associated with improved EBPR activity. GAO relative abundance also increased, challenging the assumption of competition. An Accumulibacter bin-genome was identified from a whole community metagenomic survey, and comparative analysis against extant Accumulibacter genomes suggests a close relationship to Type II. Analysis of the associated metatranscriptome data revealed that genes encoding proteins involved in the tricarboxylic acid cycle and glycolysis pathways were highly expressed, consistent with metabolic modelling results. Our findings show that tropical EBPR is indeed possible, highlight the translational potential of studying competition dynamics in full-scale waste water communities and carry implications for plant design in tropical regions.

  7. Exploring the Shift in Structure and Function of Microbial Communities Performing Biological Phosphorus Removal

    Science.gov (United States)

    Mao, Yanping; Wang, Zhiping; Li, Liguan; Jiang, Xiaotao; Zhang, Xuxiang; Ren, Hongqiang; Zhang, Tong

    2016-01-01

    A sequencing batch reactor fed mainly by acetate was operated to perform enhanced biological phosphorus removal (EBPR). A short-term pH shock from 7.0 to 6.0 led to a complete loss of phosphate-removing capability and a drastic change of microbial communities. 16S rRNA gene pyrosequencing showed that large proportions of glycogen accumulating organisms (GAOs) (accounted for 16% of bacteria) bloomed, including Candidatus Competibacter phosphatis and Defluviicoccus-related tetrad-forming organism, causing deteriorated EBPR performance. The EBPR performance recovered with time and the dominant Candidatus Accumulibacter (Accumulibacter) clades shifted from Clade IIC to IIA while GAOs populations shrank significantly. The Accumulibacter population variation provided a good opportunity for genome binning using a bi-dimensional coverage method, and a genome of Accumulibacter Clade IIC was well retrieved with over 90% completeness. Comparative genomic analysis demonstrated that Accumulibacter clades had different abilities in nitrogen metabolism and carbon fixation, which shed light on enriching different Accumulibacter populations selectively. PMID:27547976

  8. Integrative microbial community analysis reveals full-scale enhanced biological phosphorus removal under tropical conditions

    Science.gov (United States)

    Law, Yingyu; Kirkegaard, Rasmus Hansen; Cokro, Angel Anisa; Liu, Xianghui; Arumugam, Krithika; Xie, Chao; Stokholm-Bjerregaard, Mikkel; Drautz-Moses, Daniela I.; Nielsen, Per Halkjær; Wuertz, Stefan; Williams, Rohan B. H.

    2016-01-01

    Management of phosphorus discharge from human waste is essential for the control of eutrophication in surface waters. Enhanced biological phosphorus removal (EBPR) is a sustainable, efficient way of removing phosphorus from waste water without employing chemical precipitation, but is assumed unachievable in tropical temperatures due to conditions that favour glycogen accumulating organisms (GAOs) over polyphosphate accumulating organisms (PAOs). Here, we show these assumptions are unfounded by studying comparative community dynamics in a full-scale plant following systematic perturbation of operational conditions, which modified community abundance, function and physicochemical state. A statistically significant increase in the relative abundance of the PAO Accumulibacter was associated with improved EBPR activity. GAO relative abundance also increased, challenging the assumption of competition. An Accumulibacter bin-genome was identified from a whole community metagenomic survey, and comparative analysis against extant Accumulibacter genomes suggests a close relationship to Type II. Analysis of the associated metatranscriptome data revealed that genes encoding proteins involved in the tricarboxylic acid cycle and glycolysis pathways were highly expressed, consistent with metabolic modelling results. Our findings show that tropical EBPR is indeed possible, highlight the translational potential of studying competition dynamics in full-scale waste water communities and carry implications for plant design in tropical regions. PMID:27193869

  9. Role of aeration intensity on performance and microbial community profiles in a sequencing batch reaction kettle (SBRK) for wastewater nutrients rapid removal.

    Science.gov (United States)

    Xin, Xiaodong; He, Junguo; Wang, Yuefei; Feng, Jinghan; Qiu, Wei

    2016-02-01

    A lab-scale SBRK was operated to investigate the effects of aeration intensity on the system performance and microbial community dynamics within it. Results showed that the sewage nutrients was removed rapidly (just about 3-6h) with the aeration intensity increasing from 0 to 0.6MPa. Average effluent parameters were: COD below 50mg/L, NH4(+)-N less than 1mg/L, 1.5-4.5mg/L for nitrate and TP below 0.5mg/L. The highest community similarity and diversity emerged simultaneously with the aeration pressure rising from 0.2 to 0.4MPa, which was regarded as the optimal aeration intensity range. Microbial community shifted obviously and the function species of Comamonadaceae, Dechloromonas, Flavobacterium and Nitrospira dominated in the corresponding communities. RDA indicated that aeration intensity was the main factor for regulating system communities to optimize the system performance. It inferred that high aeration pressure played a key role on sewage nutrients rapid removal.

  10. Biological nitrogen removal with enhanced phosphate uptake in (AO)2SBR using single sludge system

    Institute of Scientific and Technical Information of China (English)

    JIANG Yi-feng; WANG Lin; WANG Bao-zhen; HE Sheng-bing; LUI Shuo

    2004-01-01

    Simultaneous biological phosphorus and nitrogen removal with enhanced anoxic phosphate uptake via nitrite was investigated in an anaerobic-aerobic-anoxic-aerobic sequencing batch reactor((AO)2 SBR). The system showed stable phosphorus and nitrogen removal performance, and average removals for COD, TN and TP were 90%, 91% and 96%, respectively. The conditions of pH 7.5-8.0 and temperature 32℃ were found detrimental to nitrite oxidation bacteria but favorable to ammonia oxidizers, and the corresponding specific oxygen uptake rates(SOUR) for phase 1 and 2 of nitrification process were 0.7 and 15 mgO2/(gVSS·h) in respect, which led to the nitrite accumulation in aerobic phase of(AO)2 SBR. Respiratory tests showed that 40 mgNO2-N/L did not deteriorate the sludge activity drastically, and it implied that exposure of sludge to nitrite periodically enabled the biomass to have more tolerance capacity to resist the restraining effects from nitrite. In addition, batch tests were carried out and verified that denitrifying phosphorus accumulation organisms(DPAOs) could be enriched in a single sludge system coexisting with nitrifiers by introducing an anoxic phase in an anaerobic-aerobic SBR, and the ratio of the anoxic phosphate uptake capacity to aerobic phosphate uptake capacity was 45%. It was also found that nitrite(up to 20 mgNO2-N/L) was not inhibitory to anoxic phosphate uptake and could serve as an electron acceptor like nitrate, but presented poorer efficiency compared with nitrate.

  11. Seasonal nutrient and plankton dynamics in a physical-biological model of Crater Lake

    Science.gov (United States)

    Fennel, K.; Collier, R.; Larson, G.; Crawford, G.; Boss, E.

    2007-01-01

    A coupled 1D physical-biological model of Crater Lake is presented. The model simulates the seasonal evolution of two functional phytoplankton groups, total chlorophyll, and zooplankton in good quantitative agreement with observations from a 10-year monitoring study. During the stratified period in summer and early fall the model displays a marked vertical structure: the phytoplankton biomass of the functional group 1, which represents diatoms and dinoflagellates, has its highest concentration in the upper 40 m; the phytoplankton biomass of group 2, which represents chlorophyta, chrysophyta, cryptomonads and cyanobacteria, has its highest concentrations between 50 and 80 m, and phytoplankton chlorophyll has its maximum at 120 m depth. A similar vertical structure is a reoccurring feature in the available data. In the model the key process allowing a vertical separation between biomass and chlorophyll is photoacclimation. Vertical light attenuation (i.e., water clarity) and the physiological ability of phytoplankton to increase their cellular chlorophyll-to-biomass ratio are ultimately determining the location of the chlorophyll maximum. The location of the particle maxima on the other hand is determined by the balance between growth and losses and occurs where growth and losses equal. The vertical particle flux simulated by our model agrees well with flux measurements from a sediment trap. This motivated us to revisit a previously published study by Dymond et al. (1996). Dymond et al. used a box model to estimate the vertical particle flux and found a discrepancy by a factor 2.5-10 between their model-derived flux and measured fluxes from a sediment trap. Their box model neglected the exchange flux of dissolved and suspended organic matter, which, as our model and available data suggests is significant for the vertical exchange of nitrogen. Adjustment of Dymond et al.'s assumptions to account for dissolved and suspended nitrogen yields a flux estimate that is

  12. Is anaerobic digestion effective for the removal of organic micropollutants and biological activities from sewage sludge?

    Science.gov (United States)

    Gonzalez-Gil, L; Papa, M; Feretti, D; Ceretti, E; Mazzoleni, G; Steimberg, N; Pedrazzani, R; Bertanza, G; Lema, J M; Carballa, M

    2016-10-01

    The occurrence of emerging organic micropollutants (OMPs) in sewage sludge has been widely reported; nevertheless, their fate during sludge treatment remains unclear. The objective of this work was to study the fate of OMPs during mesophilic and thermophilic anaerobic digestion (AD), the most common processes used for sludge stabilization, by using raw sewage sludge without spiking OMPs. Moreover, the results of analytical chemistry were complemented with biological assays in order to verify the possible adverse effects (estrogenic and genotoxic) on the environment and human health in view of an agricultural (re)use of digested sludge. Musk fragrances (AHTN, HHCB), ibuprofen (IBP) and triclosan (TCS) were the most abundant compounds detected in sewage sludge. In general, the efficiency of the AD process was not dependent on operational parameters but compound-specific: some OMPs were highly biotransformed (e.g. sulfamethoxazole and naproxen), while others were only slightly affected (e.g. IBP and TCS) or even unaltered (e.g. AHTN and HHCB). The MCF-7 assay evidenced that estrogenicity removal was driven by temperature. The Ames test did not show point mutation in Salmonella typhimurium while the Comet test exhibited a genotoxic effect on human leukocytes attenuated by AD. This study highlights the importance of combining chemical analysis and biological activities in order to establish appropriate operational strategies for a safer disposal of sewage sludge. Actually, it was demonstrated that temperature has an insignificant effect on the disappearance of the parent compounds while it is crucial to decrease estrogenicity. PMID:27344252

  13. Biorreator à membrana em batelada sequencial aplicado ao tratamento de esgoto visando à remoção de nutrientes Membrane sequencing batch reactor for the wastewater treatment aiming the nutrients removal

    Directory of Open Access Journals (Sweden)

    Tiago José Belli

    2012-06-01

    Full Text Available Neste trabalho, avaliou-se o desempenho de um biorreator à membrana em batelada sequencial para a remoção de nutrientes (nitrogênio e fósforo de esgoto sanitário. O reator, construído em escala piloto, foi operado durante 241 dias com tempo total de ciclo de 4 horas, sendo 5 minutos para alimentação, 55 minutos para a fase anóxica e 180 minutos para as fases de aeração e filtração (simultaneamente. Ao longo do monitoramento, foram empregados dois fluxos de filtração: 5,55 e 11,1 L.m-2.h-1, que resultaram nas taxas de troca volumétrica de 5 e 10%, respectivamente. As eficiências médias de remoção de Demanda Química de Oxigênio total, nitrogênio amoniacal e nitrogênio total alcançadas foram de 99, 98 e 96%, respectivamente. Em relação à remoção de fósforo, observou-se inicialmente um baixo rendimento do reator, sendo verificado ao longo do tempo, no entanto, uma tendência de melhora na remoção desse nutriente, atingindo eficiência média de 74% entre os dias 158 e 241. A utilização do fluxo de filtração de 5,55 L.m-2.h-1 proporcionou uma operação estável ao biorreator à membrana em batelada sequencial no que se refere à pressão transmembrana, tendo sido atingido o valor limite de 0,7 bar apenas uma vez em 181 dias de operação, ao passo que, com fluxo de 11,1 L.m-2.h-1, esse limite foi atingido 3 vezes em 55 dias.This study evaluated the performance of a membrane bioreactor sequencing batch, in pilot scale, to remove nutrients (nitrogen and phosphorus from domestic wastewater. The reactor was operated for 241 days with a total cycle time of 4 hours, with 5 minutes for feeding, 55 minutes for the anoxic phase and 180 minutes for the aeration and filtration phases (simultaneously. Throughout the monitoring, two filtration flows were employed: 5.5 and 11.1 (critical flux L.m-2.h-1, which resulted in the volume exchange rates of 5 and 10%, respectively. The removal efficiencies of total Chemical Oxygen

  14. COD, nutrient removal and disinfection efficiency of a combined subsurface and surface flow constructed wetland: A case study.

    Science.gov (United States)

    Sartori, Laura; Canobbio, Sergio; Fornaroli, Riccardo; Cabrini, Riccardo; Marazzi, Francesca; Mezzanotte, Valeria

    2016-01-01

    A constructed wetland system composed of a subsurface flow wetland, a surface flow wetland and a facultative pond was studied from July 2008 until May 2012. It was created to treat the domestic sewage produced by a hamlet of 150 inhabitants. Monthly physicochemical and microbiological analyses were carried out in order to evaluate the removal efficiency of each stage of the process and of the total treatment system. Pair-wise Student's t-tests showed that the mean removal of each considered parameter was significantly different (α = 0.05) between the various treatment phases. Two-way ANOVA and Tukey's HSD tests were used to find significant differences between wetland types and seasons in the removal efficiency of the considered water quality parameters. Significant differences in percent removal efficiency between the treatment phases were observed for total phosphorus, total nitrogen, ammonia nitrogen and organic load (expressed as Chemical Oxygen Demand). In general, the wastewater treatment was carried by the sub-superficial flow phase mainly, both in growing season and in quiescence season. Escherichia coli removal ranged from 98% in quiescence season to >99% in growing season (approximately 2-3 orders of magnitude). The inactivation of fecal bacteria was not influenced by the season, but only by the treatment phase. PMID:26552725

  15. Study on biological phosphorus removal process by Acinetobacter lwoffi: possibility to by-pass the anaerobic phase

    Energy Technology Data Exchange (ETDEWEB)

    Ghigliazza, R.; Lodi, A.; Rovatti, M. [Institute of Chemical and Process Engineering ``G.B. Bonino``, University of Genoa (Italy)

    1998-03-01

    An Acinetobacter lwoffi culture has been submitted to anaerobic/aerobic conditions in a Sequencing Batch Reactor (SBR) in order to study the ability of this strain in biological phosphorus removal process. Even by feeding a pure sodium acetate substrate, no phosphorus release has been detected during anaerobiosis, while phosphorus uptake beyond metabolic needs has been recorded during the aerobic phase; the anaerobic phase seems to have no influence on the enhanced biological phosphorus removal mechanisms. Hence aerobic batch tests have been carried out in order to verify the ability of Acinetobacter lwoffi to remove phosphorus by ``luxury uptake`` and ``overplus accumulation`` without anaerobic stress. Obtained results revealed a phosphorus removal efficiency of 75-80%. (orig.) With 5 figs., 3 tabs., 18 refs.

  16. Membrane bioreactor and nanofiltration hybrid system for reclamation of municipal wastewater: removal of nutrients, organic matter and micropollutants.

    Science.gov (United States)

    Chon, Kangmin; KyongShon, Ho; Cho, Jaeweon

    2012-10-01

    A membrane bioreactor (MBR) and nanofiltration (NF) hybrid system was investigated to demonstrate the performance of treating nitrogen, phosphorus and pharmaceuticals and personal care products (PPCPs) in municipal wastewater. With the MBR and NF (molecular weight cut off (MWCO): 210 Da), the concentration of total nitrogen (TN) and total phosphorus (TP) was effectively reduced by nitrification by MBR and negatively charged surface of NF (TN: 8.67 mgN/L and TP: 0.46 mgP/L). Biosorption and microbial decomposition in MBR seem to be major removal mechanisms for the removal of PPCPs. Among various parameters affecting the removal of PPCPs by NF, namely, physicochemical properties of the PPCPs (charge characteristics, hydrophobicity and M(W)) and membranes (MWCO and surface charge), the MWCO effect was found to be the most critical aspect. PMID:22608290

  17. Removal of the Micropollutants DEET and DEP in biological Grey Water Treatment and the Effect of DEP on microbiological Processes

    OpenAIRE

    Geiling, Eva-Linde

    2015-01-01

    The insect repellent N,N-diethyl-m-toluamide (DEET) and the plasticizer Diethyl Phthalate (DEP) are commonly used in externally applied personal care products. Washed off the skin, they are found in grey water. If the grey water is reused for high body contact applications in order to lower the potable water demand, the removal efficiency for these micropollutants (MP) during treatment is crucial. The presented Master s thesis quantifies the removal of DEET and DEP during biological grey wate...

  18. Nutrient Removal and Biomass Production in an Outdoor Pilot-Scale Phototrophic Biofilm Reactor for Effluent Polishing

    NARCIS (Netherlands)

    Boelee, N.C.; Janssen, M.; Temmink, H.; Shrestha, R.; Buisman, C.J.N.; Wijffels, R.H.

    2014-01-01

    An innovative pilot-scale phototrophic biofilm reactor was evaluated over a 5-month period to determine its capacity to remove nitrogen and phosphorus from Dutch municipal wastewater effluents. The areal biomass production rate ranged between 2.7 and 4.5 g dry weight/m2/day. The areal nitrogen and p

  19. Nutrient removal of a floating plant system receiving low- pollution wastewater: Effects of plant species and influent concentration

    Science.gov (United States)

    Duan, J. J.; Zhao, J. N.; Xue, L. H.; Yang, L. Z.

    2016-08-01

    Plant floating bed was adopted in this study to compare the purification effect of four plant species (Oenanthe javanica, Ipomoea aquatica, Hydrocotyle vulgaris, and Iris sibirica) receiving high and low treated domestic sewage. The experiment was conducted for eight months during the low temperature season. The results indicated that the average removal rates of TN and NH4+-N in I. aquatica floating bed were relatively high both under high and low influent concentration during the first stage of the experiment. During the second stage, H. vulgaris showed the best performance for nitrogen treatment, and the average removal rates of TN were 70.7% and 87.7% under high and low influent concentration, while the average removal rates of NH4 +-N were as high as 98.9% and 98.9%, accordingly. Moreover, H. vulgaris contributed most for plant assimilation to nitrogen removal among different plant floating systems. It was also found that the existence of hydrophytes effectively controlled the rise of water pH value and algae growth and reproduction, which helped to improve the aquatic environment. The results provide engineering parameters for the future design of an ecological remediation technology for low-pollution wastewater purification.

  20. Evaluation of the treatment performance of lab-scaled vertical flow constructed wetlands in removal of organic compounds, color and nutrients in azo dye-containing wastewater.

    Science.gov (United States)

    Dogdu, Gamze; Yalcuk, Arda

    2016-01-01

    The objective of this study is to examine the treatment performance of vertical flow intermittent feeding constructed wetland (VFCW) in removal of organic pollution, nutrients and color in azo-dye containing wastewater. The systems consisted of PVC reactors, some filling materials such as gravel, sand and zeolite and wetland plants including Typha angustifolia and Canna indica. The average treatment efficiency of the systems for COD, color, sulphate, NH4-N, and PO4-P were in the range of 57-63%, 94-99%, 44-48%, 39-44%, and 84-88%, respectively among the VFCW reactors. It is concluded that VFCW reactor system can effectively be used in the treatment of dye-rich wastewater, especially for the removal of color and in the reduction of COD. Biofilm formation and cleavage of azo bonds could be observed by SEM and FTIR results, respectively. Almost similar NH4-N and PO4-P removal were obtained in all reactors by using same amount of zeolite media. PMID:26248021

  1. Identification of wastewater treatment processes for nutrient removal on a full-scale WWTP by statistical methods

    DEFF Research Database (Denmark)

    Carstensen, Jakob; Madsen, Henrik; Poulsen, Niels Kjølstad;

    1994-01-01

    The introduction of on-line sensors of nutrient salt concentrations on wastewater treatment plants opens a wide new area of modelling wastewater processes. Time series models of these processes are very useful for gaining insight in real time operation of wastewater treatment systems which deal...... of the processes, i.e. including prior knowledge, with the significant effects found in data by using statistical identification methods. Rates of the biochemical and hydraulic processes are identified by statistical methods and the related constants for the biochemical processes are estimated assuming Monod...... kinetics. The models only include those hydraulic and kinetic parameters, which have shown to be significant in a statistical sense, and hence they can be quantified. The application potential of these models is on-line control, because the present state of the plant is given by the variables of the models...

  2. Nutrients removal and lipids production by Chlorella pyrenoidosa cultivation using anaerobic digested starch wastewater and alcohol wastewater.

    Science.gov (United States)

    Yang, Libin; Tan, Xiaobo; Li, Deyi; Chu, Huaqiang; Zhou, Xuefei; Zhang, Yalei; Yu, Hong

    2015-04-01

    The cultivation of microalgae Chlorella pyrenoidosa (C. pyrenoidosa) using anaerobic digested starch wastewater (ADSW) and alcohol wastewater (AW) was evaluated in this study. Different proportions of mixed wastewater (AW/ADSW=0.176:1, 0.053:1, 0.026:1, v/v) and pure ADSW, AW were used for C. pyrenoidosa cultivation. The different proportions between ADSW and AW significantly influenced biomass growth, lipids production and pollutants removal. The best performance was achieved using mixed wastewater (AW/ADSW=0.053:1, v/v), leading to a maximal total biomass of 3.01±0.15 g/L (dry weight), lipids productivity of 127.71±6.31 mg/L/d and pollutants removal of COD=75.78±3.76%, TN=91.64±4.58% and TP=90.74±4.62%.

  3. The effect of amino acids on lipid production and nutrient removal by Rhodotorula glutinis cultivation in starch wastewater.

    Science.gov (United States)

    Liu, Meng; Zhang, Xu; Tan, Tianwei

    2016-10-01

    In this paper, the components of amino acids in mixed starch wastewater (corn steep water/corn gluten water=1/3, v/v) were analyzed by GC-MS. Effects of amino acids on lipid production by Rhodotorula glutinis and COD removal were studied. The results showed that mixed starch wastewater contained 9 kinds of amino acids and these amino acids significantly improved the biomass (13.63g/L), lipid yield (2.48g/L) and COD removal compared to the basic medium (6.23g/L and 1.56g/L). In a 5L fermentor containing mixed starch wastewater as substrate to culture R. glutinis, the maximum biomass, lipid content and lipid yield reached 26.38g/L, 28.90% and 7.62g/L, with the associated removal rates of COD, TN and TP reaching 77.41%, 69.12% and 73.85%, respectively. The results revealed a promising approach for lipid production with using amino acids present in starch wastewater as an alternative nitrogen source. PMID:27420158

  4. Composição mineral de frutos cítricos na colheita Mineral nutrient removal by the harvest of citrus fruit

    Directory of Open Access Journals (Sweden)

    Ondino C. Bataglia

    1977-01-01

    fruits were sectioned in skin, pulp with juice, and seeds. It was determined the proportion among these parte and their water content. The concentration of all plant nutriente plus sodium, aluminum and cobalt was determined on the dried material. These data allowed the estimation of nutrient removal per metric ton of fresh fruit. The average of removed elements expressed in gramms per ton of fresh fruit of the nine cultivars follows this order: N-1,906; P-173; K-1,513; Ca-526; Mg-127; S-137; B-2.2; Cl-24.7; Cu-1.2; Fe-6.6; Mn-2.8; Mo-0.008; Zn-0.9; Co-0.003; Na-43.5; Al-7.6. The seeds showed to be organs where there is larger percentual quantity of the majority of macronutrients, except for K which is more abundant in the pulp plus juice. The cultivars Natal and Valencia showed the greatest nutrient removal, and Tahiti lime the lowest.

  5. Biological systems coupled for treating wastewater from processing coffee cherries: I – Removal of organic matter - doi: 10.4025/actascitechnol.v35i2.13627

    Directory of Open Access Journals (Sweden)

    Ronaldo Fia

    2013-04-01

    Full Text Available Three treatment systems consisting of upflow anaerobic filters followed by constructed wetlands (CW were evaluated in the treatment of wastewater from processing coffee cherries (WCP. The filters (F were made up of PVC (1.5 m high and 0.35 m diameter filled with gravel # 2 and SACs were made of wood boxes (1.5 m long, 0.4 m high and 0.5 m wide sealed with HDPE geomembranes and filled with gravel ‘zero’. WCP had the pH adjusted with lime to values close to 7.0 and the nutrient concentration changed to obtain a BOD/N/P ratio equal to 100/5/1. As a result, the values of influent and effluent pH remained within the range appropriate to the biological degradation of organic material. The system could not bear the shock of the organic load, which reduced the organic matter removal efficiency. Based on the analysis of performance and operating conditions employed, only the system that received the lowest organic load (F1+CW1 on the third phase, was effective in removing organic matter.  

  6. Tratamento de esgoto sanitário em reator híbrido em bateladas sequenciais: eficiência e estabilidade na remoção de matéria orgânica e nutrientes (N, P Sewage treatment in a sequencing batch hybrid reactor: efficiency and stability in organic matter and nutrient (N, P removal

    Directory of Open Access Journals (Sweden)

    Luiz Gonzaga Lamego Neto

    2011-12-01

    Full Text Available Este trabalho apresenta os resultados de estudo sobre o comportamento de um reator híbrido, operado em bateladas sequenciais, na remoção conjunta de matéria carbonácea, nitrogênio e fósforo de esgoto sanitário. Operado em ciclos de 8 horas de duração, o reator possuía em seu interior um suporte fixo com rede de nylon. Foram testadas cargas compreendidas entre 0,39 e 1,35 kgDQO.m-3.dia-1, 42 e 60 gN-NH4-.m-3.dia e 51 e 70 gP-PO4-.m-3.dia. O reator funcionou como um sistema estável e apresentou boas condições de depuração. A remoção da matéria carbonácea mostrou-se elevada, com eficiências médias de 92% de DBO5 e 80% de DQO. A remoção de nutrientes variou entre 59 e 71% para nitrogênio total e entre 45 e 67% para fósforo total. Tanto no lodo em suspensão, quanto no biofilme, foi observada a ocorrência de bactérias oxidadoras de amônio e micro-organismos responsáveis pela desnitrificação e remoção biológica de fósforo.This paper presents the results about the behavior of a sequencing batch hybrid reactor on combined removal of carbonaceous matter, nitrogen and phosphorus from sewage. Operated in 8-hour cycles, the reactor had a nylon net fixed inside. Loads between 0.39 and 1.35 kg COD.m-3.day-1, 42 and 60 gN-NH4-m-3.day-1 and 51 and 70 gP-PO4-m-3.day-1 were tested. The reactor operated as a stable system and showed good depuration conditions. The carbonaceous matter removal was high, with 92 and 80% efficiencies average to BOD5 and COD, respectively. The nutrients removal varied between 59 and 71% for total nitrogen and between 45 and 67% for total phosphorus. In both, sludge in suspension and the biofilm, occurrence of ammonium-oxidizing bacteria and microorganisms responsible for denitrification and biological phosphorus removal was observed.

  7. Removal of Refractory Organics from Biologically Treated Landfill Leachate by Microwave Discharge Electrodeless Lamp Assisted Fenton Process

    Directory of Open Access Journals (Sweden)

    Jiuyi Li

    2015-01-01

    Full Text Available Biologically treated leachate usually contains considerable amount of refractory organics and trace concentrations of xenobiotic pollutants. Removal of refractory organics from biologically treated landfill leachate by a novel microwave discharge electrodeless lamp (MDEL assisted Fenton process was investigated in the present study in comparison to conventional Fenton and ultraviolet Fenton processes. Conventional Fenton and ultraviolet Fenton processes could substantially remove up to 70% of the refractory organics in a membrane bioreactor treated leachate. MDEL assisted Fenton process achieved excellent removal performance of the refractory components, and the effluent chemical oxygen demand concentration was lower than 100 mg L−1. Most organic matters were transformed into smaller compounds with molecular weights less than 1000 Da. Ten different polycyclic aromatic hydrocarbons were detected in the biologically treated leachate, most of which were effectively removed by MDEL-Fenton treatment. MDEL-Fenton process provides powerful capability in degradation of refractory and xenobiotic organic pollutants in landfill leachate and could be adopted as a single-stage polishing process for biologically treated landfill leachate to meet the stringent discharge limit.

  8. Understanding the role of extracellular polymeric substances in an enhanced biological phosphorus removal granular sludge system.

    Science.gov (United States)

    Wang, Randeng; Peng, Yongzhen; Cheng, Zhanli; Ren, Nanqi

    2014-10-01

    The role of extracellular polymeric substances (EPS) in the enhanced biological phosphorus removal (EBPR) process was investigated in a P-accumulating granular sludge system by analyzing the distribution and transfer of P, K(+), Mg(2+) and Ca(2+) in the sludge phase, EPS, and the bulk liquid. In the sludge phase, about 30% P, 44.7% K(+), 27.7% Mg(2+), 28% Ca(2+) accumulated in the EPS at the end of aeration. The rate of P, K(+), Mg(2+) and Ca(2+) released from the EPS matrix into the bulk liquid in the anaerobic phase was faster than the rate they were adsorbed from the bulk liquid into the EPS in the aerobic phase. P, K(+), Mg(2+) and Ca(2+) were retained in EPS before transferring into the phosphorus accumulating organisms (PAOs). These results suggest that EPS play a critical role in facilitating the accumulation and transfer of P, K(+), Ca(2+) and Mg(2+) between PAO cells and bulk liquid. PMID:25063972

  9. Genome reconstruction and gene expression of "Candidatus Accumulibacter phosphatis" Clade IB performing biological phosphorus removal.

    Science.gov (United States)

    Mao, Yanping; Yu, Ke; Xia, Yu; Chao, Yuanqing; Zhang, Tong

    2014-09-01

    We report the first integrated metatranscriptomic and metagenomic analysis of enhanced biological phosphorus removal (EBPR) sludge. A draft genome of Candidatus Accumulibacter spp. strain HKU-1, a member of Clade IB, was retrieved. It was estimated to be ∼90% complete and shared average nucleotide identities of 83% and 88% with the finished genome CAP IIA UW-1 and the draft genome CAP IA UW-2, respectively. Different from CAP IIA UW-1, the phosphotransferase (pap) in polyphosphate metabolism and V-ATPase in orthophosphate transport were absent from CAP IB HKU-1. Additionally, unlike CAP IA UW-2, CAP IB HKU-1 carried the genes for carbon fixation and nitrogen fixation. Despite these differences, the key genes required for acetate uptake, glycolysis and polyhydroxyalkanoate (PHA) synthesis were conserved in all these Accumulibacter genomes. The preliminary metatranscriptomic results revealed that the most significantly up-regulated genes of CAP IB HKU-1 from the anaerobic to the aerobic phase were responsible for assimilatory sulfate reduction, genetic information processing and phosphorus absorption, while the down-regulated genes were related to N2O reduction, PHA synthesis and acetyl-CoA formation. This study yielded another important Accumulibacter genome, revealed the functional difference within the Accumulibacter Type I, and uncovered the genetic responses to EBPR stimuli at a higher resolution. PMID:25089581

  10. Chemically and biologically modified activated carbon sorbents for the removal of lead ions from aqueous media.

    Science.gov (United States)

    Mahmoud, Mohamed E; Abdel-Fattah, Tarek M; Osman, Maher M; Ahmed, Somia B

    2012-01-01

    A method is described for hybridization of the adsorption and biosorption characteristics of chemically treated commercial activated carbon and baker's yeast, respectively, for the formation of environmental friendly multifunctional sorbents. Activated carbon was loaded with baker's yeast after acid-base treatment. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) Spectroscopy were used to characterize these sorbents. Moreover, the sorption capabilities for lead (II) ions were evaluated. A value of 90 μmol g(-1) was identified as the maximum sorption capacity of activated carbon. Acid-base treatment of activated carbon was found to double the sorption capacity (140-180 μmol g(-1)). Immobilization of baker's yeast on the surface of activated carbon sorbents was found to further improve the sorption capacity efficiency of lead to 360, 510 and 560 μmol g(-1), respectively. Several important factors such as pH, contact time, sorbent dose, lead concentration and interfering ions were examined. Lead sorption process was studied and evaluated by several adsorption isotherms and found to follow the Langmuir and BET models. The potential applications of various chemically and biologically modified sorbents and biosorbents for removal of lead from real water matrices were also investigated via multistage micro-column technique and the results referred to excellent recovery values of lead (95.0-99.0 ± 3.0-5.0 %).

  11. Biological phosphate removal using a degradable carbon source produced by hydrothermal treatment of excess sludge

    Directory of Open Access Journals (Sweden)

    L. H. Haraguchi

    2006-03-01

    Full Text Available The possibility of reusing excess sludge treated by hydrothermal reaction for the purpose of improving the efficiency of the enhanced biological phosphate removal (EBPR process was investigated. Excess sludge from a fish-processing industry located in Japan was treated in high-temperature and high-pressure water, at a reaction temperature ranging from 200 to 400ºC, a pressure of 1.8 to 30MPa and a constant reaction time of 7 min. For the conditions tested, the results showed that when the reaction temperature was increased the content of readily biodegradable substrate in the total COD Cr increased. In addition, the amount of some volatile fatty acids (VFAs produced by the hydrothermal reaction increased as reaction temperature increased. From the phosphate release tests under anaerobic conditions, it was possible to demonstrate that not only the VFAs, but also the readily and slowly biodegradable substrates are used as potential carbon source by the phosphate-accumulating organisms (PAOs.

  12. Cost-performance analysis of nutrient removal in a full-scale oxidation ditch process based on kinetic modeling

    Institute of Scientific and Technical Information of China (English)

    Zheng Li; Rong Qi; Bo Wang; Zhe Zou; Guohong Wei; Min Yang

    2013-01-01

    A full-scale oxidation ditch process for treating sewage was simulated with the ASM2d model and optimized for minimal cost with acceptable performance in terms of ammonium and phosphorus removal.A unified index was introduced by integrating operational costs (aeration energy and sludge production) with effluent violations for performance evaluation.Scenario analysis showed that,in comparison with the baseline (all of the 9 aerators activated),the strategy of activating 5 aerators could save aeration energy significantly with an ammonium violation below 10%.Sludge discharge scenario analysis showed that a sludge discharge flow of 250-300 m3/day (solid retention time (SRT),13-15 days) was appropriate for the enhancement of phosphorus removal without excessive sludge production.The proposed optimal control strategy was:activating 5 rotating disks operated with a mode of "111100100" ("1"represents activation and "0" represents inactivation) for aeration and sludge discharge flow of 200 m3/day (SRT,19 days).Compared with the baseline,this strategy could achieve ammonium violation below 10% and TP violation below 30% with substantial reduction of aeration energy cost (46%) and minimal increment of sludge production (< 2%).This study provides a useful approach for the optimization of process operation and control.

  13. Long-term development of subalpine lakes : effects of nutrients, climate and hydrological variability as assessed by biological and geochemical sediment proxies

    OpenAIRE

    Milan, Manuela

    2016-01-01

    Sediment records of two Italian subalpine lakes (Lake Garda and Lake Ledro) were analyzed in order to reconstruct their ecological evolution over the past several hundred years. A multi-proxy and multi-site approach was applied in order to disentangle the effects of local anthropogenic forcings, such as nutrients, and climate impacts on the two lakes and their catchments. Biological indicators (sub-fossil pigments, diatoms and Cladocera) were used to reconstruct changes in the aquatic food we...

  14. Comparative assessment of phthalate removal and risk in biological wastewater treatment systems of developing countries and small communities.

    Science.gov (United States)

    Gani, Khalid Muzamil; Kazmi, Absar Ahmad

    2016-11-01

    Phthalates are widely used in plastic and personnel care products. Being non-steroid endocrine disrupting compounds, their exposure have toxic effects on aquatic life and human health. The aim of this study was a comparative assessment of their fate and risk in full scale wastewater treatment along with influence of seasonal variations. Four priority phthalates, Diethylphthalate (DEP), Dibutylphthalate (DBP), Benzylbutyl phthalate (BBP) and Diethylhexyl phthalate (DEHP) were chosen for this study and wastewater treatment plants investigated were designed as nutrient removal based sequencing batch reactor (SBR), conventional activated sludge process (ASP) and up flow anaerobic sludge blanket (UASB) with polishing pond. Results showed that the main removal mechanism of phthalates was biotransformation with removal contribution of 74% in SBR, 65% in conventional ASP and 37% in UASB. Overall removal of phthalates was maximum in the treatment combination of UASB and pond (83%) followed by SBR (80%) and conventional ASP (74%). Seasonal influences on occurrence, removal and risk of these phthalates were also studied. The concentration of DEP, DBP and DEHP in untreated wastewater increased by 2, 7 and 2μg/L, respectively in summer. However in sludge, only large molecular weight phthalates BBP and DEHP increased in winter by 3mg/kg and 12mg/kg, respectively. Seasonal variations in removal of phthalates were discrepant in each process with better removal during summer. Risk assessment of phthalates to aquatic life showed that there is no potential risk of DEP, DBP and BBP from effluents of treatment plants however risk quotient of DEHP was in the range of 27-73 in both seasons which indicate probable risk to aquatic organisms. Phthalate risk to human beings estimated by daily intake of phthalates was in the range of 0.3±0.1 to 20±0.7ng/kg/d and far below their respective reference dosages, demonstrating the potential of these treatment plants to reduce the risk of

  15. A novel approach for phosphorus recovery and no wasted sludge in enhanced biological phosphorus removal process with external COD addition.

    Science.gov (United States)

    Xia, Cheng-Wang; Ma, Yun-Jie; Zhang, Fang; Lu, Yong-Ze; Zeng, Raymond J

    2014-01-01

    In enhanced biological phosphorus removal (EBPR) process, phosphorus (P) in wastewater is removed via wasted sludge without actual recovery. A novel approach to realize phosphorus recovery with special external chemical oxygen demand (COD) addition in EBPR process was proposed. During the new operating approach period, it was found that (1) no phosphorus was detected in the effluent; (2) with an external addition of 10 % of influent COD amount, 79 % phosphorus in the wastewater influent was recovered; (3) without wasted sludge, the MLVSS concentration in the system increased from 2,010 to 3,400 mg/L and kept stable after day 11 during 24-day operating period. This demonstrates that the novel approach is feasible to realize phosphorus recovery with no wasted sludge discharge in EBPR process. Furthermore, this approach decouples P removal and sludge age, which may enhance the application of membrane bioreactor for P removal. PMID:24122666

  16. Ammonium removal of drinking water at low temperature by activated carbon filter biologically enhanced with heterotrophic nitrifying bacteria.

    Science.gov (United States)

    Qin, Wen; Li, Wei-Guang; Zhang, Duo-Ying; Huang, Xiao-Fei; Song, Yang

    2016-03-01

    We sought to confirm whether use of Acinetobacter strains Y7 and Y16, both strains of heterotrophic nitrifying bacteria, was practical for removing ammonium (NH4 (+)-N) from drinking water at low temperatures. To test this, ammonium-containing drinking water was treated with strains Y7 and Y16 at 8 and 2 °C. Continuous ammonium treatment was conducted in order to evaluate the performance of three biologically enhanced activated carbon (BEAC) filters in removing ammonium. The three BEAC filters were inoculated with strain Y7, strain Y16, and a mixture of strains Y7 and Y16, respectively. A granular activated carbon (GAC) filter, without inoculation by any strains, was tested in parallel with the BEAC filters as control. The results indicated that NH4 (+)-N removal was significant when a BEAC filter was inoculated with the mixture of strains Y7 and Y16 (BEAC-III filter). Amounts of 0.44 ± 0.05 and 0.25 ± 0.05 mg L(-1) NH4 (+)-N were removed using the BEAC-III filter at 8 and 2 °C, respectively. These values were 2.8-4.0-fold higher than the values of ammonium removal acquired using the GAC filter. The synergistic effect of using strains Y7 and Y16 in concert was the cause of the high-ammonium removal efficiency achieved by using the BEAC-III filter at low temperatures. In addition, a high C/N ratio may promote NH4 (+)-N removal efficiency by improving biomass and microbial activity. This study provides new insight into the use of biofilters to achieve biological removal of ammonium at low temperature. PMID:26527340

  17. The potential role of 'Candidatus Microthrix parvicella' in phosphorus removal during sludge bulking in two full-scale enhanced biological phosphorus removal plants.

    Science.gov (United States)

    Wang, Juan; Qi, Rong; Liu, Miaomiao; Li, Qian; Bao, Haipeng; Li, Yaming; Wang, Shen; Tandoi, Valter; Yang, Min

    2014-01-01

    We investigated the bacterial community compositions and phosphorus removal performance under sludge bulking and non-bulking conditions in two biological wastewater treatment systems (conventional A²/O (anaerobic/anoxic/aerobic) and inverted A²/O (anoxic/anaerobic/aerobic) processes) receiving the same raw wastewater. Sludge bulking resulted in significant shift in bacterial compositions from Proteobacteria dominance to Actinobacteria dominance, characterized by the significant presence of filamentous 'Candidatus Microthrix parvicella'. Quantitative real-time polymerase chain reaction (PCR) analysis revealed that the relative abundance of 'Candidatus Accumulibacter phosphatis', a key polyphosphate-accumulating organism responsible for phosphorus removal, with respect to 16s rRNA genes of total bacteria was 0.8 and 0.7%, respectively, for the conventional and inverted A²/O systems when sludge bulking occurred, which increased to 8.2 and 12.3% during the non-bulking period. However, the total phosphorus removal performance during the bulking period (2-week average: 97 ± 1 and 96 ± 1%, respectively) was not adversely affected comparable to that during the non-bulking period (2-week average: 96 ± 1 and 96 ± 1%, respectively). Neisser staining revealed the presence of large polyphosphate granules in 'Candidatus Microthrix parvicella', suggesting that this microbial group might have been responsible for phosphorus removal during the sludge bulking period when 'Candidatus Accumulibacter phosphatis' was excluded from the systems. PMID:25051486

  18. Simultaneous Organics and Nutrients Removal from Domestic Wastewater in a Combined Cylindrical Anoxic/Aerobic Moving Bed Biofilm Reactor

    Directory of Open Access Journals (Sweden)

    Husham T. Ibrahim

    2014-03-01

    Full Text Available The aim of present study was to design and construct an continuous up-flow pilot scale Moving Bed Biofilm Reactor (MBBR which is consists of combined cylindrical Anoxic/Aerobic MBBR in nested form with anoxic/aerobic volume ratio equal to 0.16 to treated 4 m3 /days of domestic wastewater in Chongqing city at Southwest China. The treatment must be satisfactory to meet with grade B of discharge standard of pollutants for municipal wastewater treatment plant in China (GB/T18918-2002. Kaldnes (K1 media was used as a carrier in both reactors at a media fill ratio equal to 50%. The reactors was operated under the Anoxic/Oxic (An/O process which must meet stringent TN limits without sludge returning into the system and only an internal recycling was performed from aerobic to anoxic reactor. After developing the biofilm on the media, reactor was operated at 3 different Hydraulic Residence Time (HRT ranging from 4.95 to 8.25 h. During operation the internal recycle ratio to eliminate nitrogen compounds were 100% of inflow rate and the average Dissolved Oxygen concentration (DO in aerobic and anoxic MBBRs were 4.49 and 0.16 mg/L, respectively. The obtained results showed that the HRT of 6.2 h was suitable for simultaneous removal of COD, NH4+-N, TN and TP. In this HRT the average removal efficiencies were 93.15, 98.06, 71.67 and 90.88% for COD, NH4+-N, TN and TP, respectively.

  19. Simultaneous nutrient removal, optimised CO2 mitigation and biofuel feedstock production by Chlorogonium sp. grown in secondary treated non-sterile saline sewage effluent.

    Science.gov (United States)

    Lee, Kwan Yin; Ng, Tsz Wai; Li, Guiying; An, Taicheng; Kwan, Ka Ki; Chan, King Ming; Huang, Guocheng; Yip, Ho Yin; Wong, Po Keung

    2015-10-30

    The phycoremediation process has great potential for effectively addressing environmental pollution. To explore the capabilities of simultaneous algal nutrient removal, CO2 mitigation and biofuel feedstock production from spent water resources, a Chlorogonium sp. isolated from a tilapia pond in Hong Kong was grown in non-sterile saline sewage effluent for a bioremediation study. With high removal efficiencies of NH3-N (88.35±14.39%), NO3(-)-N (85.39±14.96%), TN (93.34±6.47%) and PO4(3-)-P (91.80±17.44%), Chlorogonium sp. achieved a CO2 consumption rate of 58.96 mg L(-1) d(-1), which was optimised by the response surface methodology. Under optimised conditions, the lipid content of the algal biomass reached 24.26±2.67%. Overall, the isolated Chlorogonium sp. showed promising potential in the simultaneous purification of saline sewage effluent in terms of tertiary treatment and CO2 sequestration while delivering feedstock for potential biofuel production in a waste-recycling manner.

  20. Metabolic modelling of full-scale enhanced biological phosphorus removal sludge.

    Science.gov (United States)

    Lanham, Ana B; Oehmen, Adrian; Saunders, Aaron M; Carvalho, Gilda; Nielsen, Per H; Reis, Maria A M

    2014-12-01

    This study investigates, for the first time, the application of metabolic models incorporating polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) towards describing the biochemical transformations of full-scale enhanced biological phosphorus removal (EBPR) activated sludge from wastewater treatment plants (WWTPs). For this purpose, it was required to modify previous metabolic models applied to lab-scale systems by incorporating the anaerobic utilisation of the TCA cycle and the aerobic maintenance processes based on sequential utilisation of polyhydroxyalkanoates, followed by glycogen and polyphosphate. The abundance of the PAO and GAO populations quantified by fluorescence in situ hybridisation served as the initial conditions of each biomass fraction, whereby the models were able to describe accurately the experimental data. The kinetic rates were found to change among the four different WWTPs studied or even in the same plant during different seasons, either suggesting the presence of additional PAO or GAO organisms, or varying microbial activities for the same organisms. Nevertheless, these variations in kinetic rates were largely found to be proportional to the difference in acetate uptake rate, suggesting a viable means of calibrating the metabolic model. The application of the metabolic model to full-scale sludge also revealed that different Accumulibacter clades likely possess different acetate uptake mechanisms, as a correlation was observed between the energetic requirement for acetate transport across the cell membrane with the diversity of Accumulibacter present. Using the model as a predictive tool, it was shown that lower acetate concentrations in the feed as well as longer aerobic retention times favour the dominance of the TCA metabolism over glycolysis, which could explain why the anaerobic TCA pathway seems to be more relevant in full-scale WWTPs than in lab-scale systems. PMID:25222332

  1. Biological mechanisms associated with triazophos (TAP) removal by horizontal subsurface flow constructed wetlands (HSFCW).

    Science.gov (United States)

    Wu, Juan; Feng, Yuqin; Dai, Yanran; Cui, Naxin; Anderson, Bruce; Cheng, Shuiping

    2016-05-15

    Triazophos (TAP) is a widely used pesticide that is easily accumulated in the environment due to its relatively high stability: this accumulation from agricultural runoff results in potential hazards to aquatic ecosystems. Constructed wetlands are generally considered to be an effective technology for treating TAP polluted surface water. However, knowledge about the biological mechanisms of TAP removal is still lacking. This study investigates the responses of a wetland plant (Canna indica), substrate enzymes and microbial communities in bench-scale horizontal subsurface-flow constructed wetlands (HSCWs) loaded with different TAP concentrations (0, 0.1, 0.5 and 5 mg · L(-1)). The results indicate that TAP stimulated the activities of superoxide dismutase (SOD) and peroxidase (POD) in the roots of C. indica. The highest TAP concentrations significantly inhibited photosynthetic activities, as shown by a reduced effective quantum yield of PS II (ΦPS II) and lower electron transport rates (ETR). However, interestingly, the lower TAP loadings exhibited some favorable effects on these two variables, suggesting that C. indica is a suitable species for use in wetlands designed for treatment of low TAP concentrations. Urease and alkaline phosphatase (ALP) in the wetland substrate were activated by TAP. Two-way ANOVA demonstrated that urease activity was influenced by both the TAP concentrations and season, while acidphosphatase (ACP) only responded to seasonal variations. Analysis of high throughput sequencing of 16S rRNA revealed seasonal variations in the microbial community structure of the wetland substrate at the phylum and family levels. In addition, urease activity had a greater correlation with the relative abundance of some functional microbial groups, such as the Bacillaceae family, and the ALP and ACP may be influenced by the plant more than substrate microbial communities. PMID:26897579

  2. Restoration of Shallow Lakes in Subtropical and Tropical China: Response of Nutrients and Water Clarity to Biomanipulation by Fish Removal and Submerged Plant Transplantation

    Directory of Open Access Journals (Sweden)

    Jinlei Yu

    2016-10-01

    Full Text Available Fish removal has been used to restore temperate lakes, and positive effects on ecological state and water clarity have frequently been recorded in many lakes. Recently, a supplementary measure, transplantation of submerged macrophytes after fish removal, has been applied to restore warm Chinese shallow lakes in order to compensate for the expected lack of increasing grazing control of phytoplankton after the biomanipulation. These measures have successfully shifted turbid warm lakes to a clear water state, but little is known about the responses to restoration of key physico-chemical variables. We analyzed the seasonal variation in nutrient concentrations in two subtropical and one tropical biomanipulated shallow Chinese lakes subjected to restoration. In all three lakes, a marked decline occurred in the concentrations of lake total nitrogen (TN, total phosphorus (TP, total suspended solids (TSS, and chlorophyll a (Chl a, while the transparency (SD:WD ratio, Secchi depth to water depth ratio increased. A clear water state was established, lasting so far for 7 to 23 months, and TN, TP, Chl a, and TSS levels in the three restored lakes decreased to, on average, 49%, 58%, 41%, and 18% of the level prior to restoration and/or the level in a reference lake, respectively, while the annual mean SD:WD ratio exhibited a 1.5–4 fold increase. In conclusion, lake restoration by transplantation of submerged macrophytes after fish removal had major positive effects on the physico-chemical variables in our study lakes. However, continuous control of omnivorous and herbivorous fish biomass is recommended as the fish typically present in warm, shallow lakes to some extent feed on submerged macrophytes, when available.

  3. Equatorial Pacific peak in biological production regulated by nutrient and upwelling during the late Pliocene/early Pleistocene cooling

    Directory of Open Access Journals (Sweden)

    J. Etourneau

    2013-08-01

    Full Text Available The largest increase in export production in the eastern Pacific of the last 5.3 Myr (million years occurred between 2.2 and 1.6 Myr, a time of major climatic and oceanographic reorganization in the region. Here, we investigate the causes of this event using reconstructions of export production, nutrient supply and oceanic conditions across the Pliocene–Pleistocene in the eastern equatorial Pacific (EEP for the last 3.2 Myr. Our results indicate that the export production peak corresponds to a cold interval marked by high nutrient supply relative to consumption, as revealed by the low bulk sedimentary 15N/14N (δ15N and alkenone-derived sea surface temperature (SST values. This ∼0.6 million year long episode of enhanced delivery of nutrients to the surface of the EEP was predominantly initiated through the upwelling of nutrient-enriched water sourced in high latitudes. In addition, this phenomenon was likely promoted by the regional intensification of upwelling in response to the development of intense Walker and Hadley atmospheric circulations. Increased nutrient consumption in the polar oceans and enhanced denitrification in the equatorial regions restrained nutrient supply and availability and terminated the high export production event.

  4. Biological removal of pharmaceutical compounds using white-rot fungi with concomitant FAME production of the residual biomass.

    Science.gov (United States)

    Vasiliadou, I A; Sánchez-Vázquez, R; Molina, R; Martínez, F; Melero, J A; Bautista, L F; Iglesias, J; Morales, G

    2016-09-15

    The efficiency of two white-rot fungi (WRF), Trametes versicolor and Ganoderma lucidum, to eliminate thirteen pharmaceutical pollutants with concomitant biodiesel production from the accumulating lipid content after treatment, was examined. The removal efficiency was studied using both individual and combined strains. The results of individual and combined strains showed a total removal (100%) of diclofenac (DCF), gemfibrozil (GFZ), ibuprofen (IBP), progesterone (PGT) and ranitidine (RNT). Lower removals were achieved for 4-acetamidoantipyrin (AAA), clofibric acid (ACF), atenolol (ATN), caffeine (CFN), carbamazepine (CZP), hydrochlorothiazide (HCT), sulfamethoxazole (SMX) and sulpiride (SPD), although the combination of both strains enhanced the system's efficiency, with removals ranging from 15 to 41%. This increase of the removal efficiency when combining both strains was attributed to the interactions developed between them (i.e., competition). Results from enzymatic and cytochrome P450 examination suggested that both extracellular (laccase, MnP, LiP) and intracellular oxidation mechanisms participate in the biological removal of pharmaceuticals. On the other hand, the "green" potential of the fungal sludge generated during the biological removal process was assessed for biodiesel production by means of one-step direct (in-situ) transformation. This process consists of the simultaneous extraction and conversion of lipids contained in the sludge by catalytic esterification/transesterification using a robust acid heterogeneous Zr-SBA-15 catalyst. This catalytic system provided conversions close to 80% of the saponifiable fraction (including free fatty acids and glycerides) in the presence of high amount of impurities. The overall weight FAME yield, based on the initial dried mass, was close to 30% for both strains. PMID:27233048

  5. Biological phosphorus removal from abattoir wastewater at very short sludge ages mediated by novel PAO clade Comamonadaceae.

    Science.gov (United States)

    Ge, Huoqing; Batstone, Damien J; Keller, Jürg

    2015-02-01

    Recent increases in global phosphorus costs, together with the need to remove phosphorus from wastewater to comply with water discharge regulations, make phosphorus recovery from wastewater economically and environmentally attractive. Biological phosphorus (Bio-P) removal process can effectively capture the phosphorus from wastewater and concentrate it in a form that is easily amendable for recovery in contrast to traditional (chemical) phosphorus removal processes. However, Bio-P removal processes have historically been operated at medium to long solids retention times (SRTs, 10-20 days typically), which inherently increases the energy consumption while reducing the recoverable carbon fraction and hence makes it incompatible with the drive towards energy self-sufficient wastewater treatment plants. In this study, a novel high-rate Bio-P removal process has been developed as an energy efficient alternative for phosphorus removal from wastewater through operation at an SRT of less than 4 days. The process was most effective at an SRT of 2-2.5 days, achieving >90% phosphate removal. Further reducing the SRT to 1.7 days resulted in a loss of Bio-P activity. 16S pyrotag sequencing showed the community changed considerably with changes in the SRT, but that Comamonadaceae was consistently abundant when the Bio-P activity was evident. FISH analysis combined with DAPI staining confirmed that bacterial cells of Comamonadaceae arranged in tetrads contained polyphosphate, identifying them as the key polyphosphate accumulating organisms at these low SRT conditions. Overall, this paper demonstrates a novel, high-rate phosphorus removal process that can be effectively integrated with short SRT, energy-efficient carbon removal and recovery processes. PMID:25481076

  6. Enhanced biological phosphorus removal. Carbon sources, nitrate as electron acceptor, and characterization of the sludge community

    Energy Technology Data Exchange (ETDEWEB)

    Christensson, M.

    1997-10-01

    Enhanced biological phosphorus removal (EBPR) was studied in laboratory scale experiments as well as in a full scale EBPR process. The studies were focused on carbon source transformations, the use of nitrate as an electron acceptor and characterisation of the microflora. A continuous anaerobic/aerobic laboratory system was operated on synthetic wastewater with acetate as sole carbon source. An efficient EBPR was obtained and mass balances over the anaerobic reactor showed a production of 1.45 g poly-{beta}-hydroxyalcanoic acids (PHA), measured as chemical oxygen demand (COD), per g of acetic acid (as COD) taken up. Furthermore, phosphate was released in the anaerobic reactor in a ratio of 0.33 g phosphorus (P) per g PHA (COD) formed and 0.64 g of glycogen (COD) was consumed per g of acetic acid (COD) taken up. Microscopic investigations revealed a high amount of polyphosphate accumulating organisms (PAO) in the sludge. Isolation and characterisation of bacteria indicated Acinetobacter spp. to be abundant in the sludge, while sequencing of clones obtained in a 16S rDNA clone library showed a large part of the bacteria to be related to the high mole % G+C Gram-positive bacteria and only a minor fraction to be related to the gamma-subclass of proteobacteria to which Acinetobacter belongs. Operation of a similar anaerobic/aerobic laboratory system with ethanol as sole carbon source showed that a high EBPR can be achieved with this compound as carbon source. However, a prolonged detention time in the anaerobic reactor was required. PHA were produced in the anaerobic reactor in an amount of 1.24 g COD per g of soluble DOC taken up, phosphate was released in an amount of 0.4-0.6 g P per g PHA (COD) produced and 0.46 g glycogen (COD) was consumed per g of soluble COD taken up. Studies of the EBPR in the UCT process at the sewage treatment plant in Helsingborg, Sweden, showed the amount of volatile fatty acids (VFA) available to the PAO in the anaerobic stage to be

  7. An efficient process for wastewater treatment to mitigate free nitrous acid generation and its inhibition on biological phosphorus removal

    OpenAIRE

    Zhao, Jianwei; Wang, Dongbo; Li, Xiaoming; Yang, Qi; Chen, Hongbo; Zhong, Yu; An, Hongxue; Zeng, Guangming

    2015-01-01

    Free nitrous acid (FNA), which is the protonated form of nitrite and inevitably produced during biological nitrogen removal, has been demonstrated to strongly inhibit the activity of polyphosphate accumulating organisms (PAOs). Herein we reported an efficient process for wastewater treatment, i.e., the oxic/anoxic/oxic/extended-idle process to mitigate the generation of FNA and its inhibition on PAOs. The results showed that this new process enriched more PAOs which thereby achieved higher ph...

  8. Effect of different carbon sources on the biological phosphorus removal by a sequencing batch reactor using pressurized pure oxygen

    OpenAIRE

    Wei, Jie; Imai, Tsuyoshi; Higuchi, Takaya; Arfarita, Novi; YAMAMOTO, Koichi; Sekine, Masahiko; Kanno, Ariyo

    2014-01-01

    The effect of different carbon source on the efficiency of enhanced biological phosphorus removal (EBPR) from synthetic wastewater with acetate and two ratios of acetate/starch as a carbon source was investigated. Three pressurized pure oxygen sequencing batch reactor (POSBR) experiments were operated. The reactors (POSBR1, POSBR2 and POSBR3) were developed and studied at different carbon source ratios of 100% acetate, 75% acetate plus 25% starch and 50% acetate plus 50% starch, respectively....

  9. Chemically enhanced biological NOx removal from flue gases : nitric oxide and ferric EDTA reduction in BioDeNox reactors

    OpenAIRE

    Maas,, F.

    2005-01-01

    The emission of nitrogen oxides (NOx) to the atmosphere is a major environmental problem. To abate NOx emissions from industrial flue gases, to date, mainly chemical processes like selective catalytic reduction (SCR) are applied. All these processes require high temperatures (>300 °C) and expensive catalysts. Therefore, biological NOx removal techniques using denitrification may represent promising alternatives for the conventional SCR techniques. However, water based biofiltration require...

  10. Some ozone advanced oxidation processes to improve the biological removal of selected pharmaceutical contaminants from urban wastewater

    OpenAIRE

    Espejo, Azahara; Aguinaco, Almudena; Amat Payá, Ana María; Fernando J. Beltrán

    2014-01-01

    Removal of nine pharmaceutical compounds¿acetaminophen (AAF), antipyrine (ANT), caffeine (CAF), carbamazepine (CRB), diclofenac (DCF), hydrochlorothiazide (HCT), ketorolac (KET), metoprolol (MET) and sulfamethoxazole (SMX)¿spiked in a primary sedimentation effluent of a municipal wastewater has been studied with sequential aerobic biological and ozone advanced oxidation systems. Combinations of ozone, UVA black light and Fe(III) or Fe3O4 constituted the chemical systems. During the ...

  11. Modeling the Performance of Biological Rapid Sand Filters Used to Remove Ammonium, Iron, and Manganese From Drinking Water

    OpenAIRE

    Lee, Carson; Albrechtsen, Hans-Jørgen; Smets, Barth F.; Binning, Philip John

    2012-01-01

    Although biological rapid sand filters are a well established technology for treating drinking water, there is still a lack of scientific understanding of the processes controlling their performance. For example, the distribution and role of microorganisms in contaminant removal in the filter has not been described. As a result, the design and operation of these filters is based on rules of thumb rather than firm scientific understanding. The goal of this research is to characterize the under...

  12. Long term operation of continuous-flow system with enhanced biological phosphorus removal granules at different COD loading.

    Science.gov (United States)

    Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie

    2016-09-01

    In this study, a continuous-flow system with enhanced biological phosphorus removal (EBPR) granules was operated at different COD concentrations (200, 300 and 400mgL(-)(1)) to investigate the effect of COD loading on this system. The results showed that when the COD concentration in influent was increased to 400mgL(-)(1), the anaerobic COD removal efficiency and total phosphorus removal efficiency reduced obviously and the settling ability of granules deteriorated due to the proliferation of filamentous bacteria. Moreover, high COD loading inhibited the EPS secretion and destroyed the stability of granules. Results of high-through pyrosequencing indicated that filamentous bacteria had a competitive advantage over polyphosphate-accumulating organisms (PAOs) at high COD loading. The performance of system, settling ability of granules and proportion of PAOs gradually recovered to the initial level after the COD concentration was reduced to 200mgL(-)(1) on day 81. PMID:27295254

  13. A DO- and pH-based early warning system of nitrification inhibition for biological nitrogen removal processes.

    Science.gov (United States)

    Hong, Seil; Choi, Il; Lim, Byung Jin; Kim, Hyunook

    2012-01-01

    In Korea, more than 80% of municipal wastewater treatment plants (WWTPs) with capacities of 500 m3·d-1 or more are capable of removing nitrogen from wastewater through biological nitrification and denitrification processes. Normally, these biological processes show excellent performance, but if a toxic chemical is present in the influent to a WWTP, the biological processes (especially, the nitrification process) may be affected and fail to function normally; nitrifying bacteria are known very vulnerable to toxic substances. Then, the toxic compound as well as the nitrogen in wastewater may be discharged into a receiving water body without any proper treatment. Moreover, it may take significant time for the process to return back its normal state. In this study, a DO- and pH-based strategy to identify potential nitrification inhibition was developed to detect early the inflow of toxic compounds to a biological nitrogen removal process. This strategy utilizes significant changes observed in the oxygen uptake rate and the pH profiles of the mixed liquor when the activity of nitrifying bacteria is inhibited. Using the strategy, the toxicity from test wastewater with 2.5 mg·L-1 Hg2+, 0.5 mg·L-1 allythiourea, or 0.25 mg·L-1 chloroform could be successfully detected. PMID:23443381

  14. A DO- and pH-Based Early Warning System of Nitrification Inhibition for Biological Nitrogen Removal Processes

    Directory of Open Access Journals (Sweden)

    Hyunook Kim

    2012-11-01

    Full Text Available In Korea, more than 80% of municipal wastewater treatment plants (WWTPs with capacities of 500 m3·d−1 or more are capable of removing nitrogen from wastewater through biological nitrification and denitrification processes. Normally, these biological processes show excellent performance, but if a toxic chemical is present in the influent to a WWTP, the biological processes (especially, the nitrification process may be affected and fail to function normally; nitrifying bacteria are known very vulnerable to toxic substances. Then, the toxic compound as well as the nitrogen in wastewater may be discharged into a receiving water body without any proper treatment. Moreover, it may take significant time for the process to return back its normal state. In this study, a DO- and pH-based strategy to identify potential nitrification inhibition was developed to detect early the inflow of toxic compounds to a biological nitrogen removal process. This strategy utilizes significant changes observed in the oxygen uptake rate and the pH profiles of the mixed liquor when the activity of nitrifying bacteria is inhibited. Using the strategy, the toxicity from test wastewater with 2.5 mg·L−1 Hg2+, 0.5 mg·L−1 allythiourea, or 0.25 mg·L−1 chloroform could be successfully detected.

  15. Removal of Review and Reclassification Procedures for Biological Products Licensed Prior to July 1, 1972. Final rule.

    Science.gov (United States)

    2016-02-12

    The Food and Drug Administration (FDA, the Agency, or we) is removing two regulations that prescribe procedures for FDA's review and classification of biological products licensed before July 1, 1972. FDA is taking this action because the two regulations are obsolete and no longer necessary in light of other statutory and regulatory authorities established since 1972, which allow FDA to evaluate and monitor the safety and effectiveness of all biological products. In addition, other statutory and regulatory authorities authorize FDA to revoke a license for biological products because they are not safe and effective, or are misbranded. FDA is taking this action as part of its retrospective review of its regulations to promote improvement and innovation. PMID:26878738

  16. Biological removal of phenol from saline wastewater using a moving bed biofilm reactor containing acclimated mixed consortia.

    Science.gov (United States)

    Nakhli, Seyyed Ali Akbar; Ahmadizadeh, Kimia; Fereshtehnejad, Mahmood; Rostami, Mohammad Hossein; Safari, Mojtaba; Borghei, Seyyed Mehdi

    2014-01-01

    In this study, the performance of an aerobic moving bed biofilm reactor (MBBR) was assessed for the removal of phenol as the sole substrate from saline wastewater. The effect of several parameters namely inlet phenol concentration (200-1200 mg/L), hydraulic retention time (8-24 h), inlet salt content (10-70 g/L), phenol shock loading, hydraulic shock loading and salt shock loading on the performance of the 10 L MBBR inoculated with a mixed culture of active biomass gradually acclimated to phenol and salt were evaluated in terms of phenol and chemical oxygen demand (COD) removal efficiencies. The results indicated that phenol and COD removal efficiencies are affected by HRT, phenol and salt concentration in the bioreactor saline feed. The MBBR could remove up to 99% of phenol and COD from the feed saline wastewater at inlet phenol concentrations up to 800 mg/L, HRT of 18 h and inlet salt contents up to 40 g/L. The reactor could also resist strong shock loads. Furthermore, measuring biological quantitative parameters indicated that the biofilm plays a main role in phenol removal. Overall, the results of this investigation revealed that the developed MBBR system with high concentration of the active mixed biomass can play a prominent role in order to treat saline wastewaters containing phenol in industrial applications as a very efficient and flexible technology.

  17. The Potato Systems Planner: Integrating Cropping System Impacts on Crop Yield and Quality, Soil Biology, Nutrient Cycling, Diseases, and Economics

    Science.gov (United States)

    Finding and developing profitable cropping systems is a high priority for the potato industry. Consequently, an interdisciplinary team of ARS scientists from the New England Plant, Soil, & Water Laboratory evaluated 14 different rotations for their impacts on crop yield and quality, nutrient availa...

  18. Biological removal of air loaded with a hydrogen sulfide and ammonia mixture

    Institute of Scientific and Technical Information of China (English)

    CHEN Ying-xu; YIN Jun; FANG Shi

    2004-01-01

    The nuisance impact of air pollutant emissions from wastewater pumping stations is a major issue of concern to China. Hydrogen sulfide and ammonia are commonly the primary odor and are important targets for removal. An alternative control technology, biofiltration, was studied. The aim of this study is to investigate the potential of unit systems packed with compost in terms of ammonia and hydrogen sulfide emissions treatment, and to establish optimal operating conditions for a full-scale conceptual design. The laboratory scale biofilter packed with compost was continuously supplied with hydrogen sulfide and ammonia gas mixtures. A volumetric load of less than 150 gH2S/(m3· d) and 230 gNH3/(m3· d) was applied for about fifteen weeks. Hydrogen sulfide and ammonia elimination occurred in the biofilter simultaneously. The removal efficiency, removal capacity and removal kinetics in the biofilter were studied. The hydrogen sulfide removal efficiency reached was very high above 99%, and ammonia removal efficiency was about 80%. Hydrogen sulfide was oxidized into sulphate. The ammonia oxidation products were nitrite and nitrate. Ammonia in the biofilter was mainly removed by adsorption onto the carrier material and by absorption into the water fraction of the carrier material. High percentages of hydrogen sulfide or ammonia were oxidized in the first section of the column. Through kinetics analysis, the presence of amrronia did not hinder the hydrogen sulfide removal. According to the relationship between pressure drop and gas velocity for the biofilter and Reynolds number, non-Darcy flow can be assumed to represent the flow in the medium.

  19. Effect of Sludge Type on Enhanced Biological Phosphorus Removal in Sequencing Batch Reactors

    Science.gov (United States)

    Li, Xing; Gao, Dawen; Zhang, Baihui

    2010-11-01

    Aerobic granulation technology has become a novel biotechnology for wastewater treatment. However, the study of distinct properties and characteristics of phosphorus removal between granules and flocculent sludge are still sparse in EBPR. Two SBRs were concurrently operated to investigate the different phosphorus removal characteristics between granules (R1) and flocculate sludge (R2). Results indicated that R2 had a faster progress for enriching phosphorus-accumulating organisms compared with R1, and the phosphorus removal reached the steady state after 40 days in R1 but only 30 days in R2. The moisture content of granules (85.63%) was smaller than that (91.36%) in R2, and the granules had a higher removal efficiency of NH4+-N. However, flocculent sludge could release and take up more phosphorus. The special phosphorus release rate (SPRR) and special phosphorus uptake rate (SPUR) were 8.818 mg/gVSSṡh and 9.921 mg/gVSSṡh in R2 which were consistently larger than that (0.999 mg/gVSSṡh and 0.754 mg/gVSSṡh) in R1. The results of DGGE of PCR-amplified 16SrDNA fragments revealed that the diversity and the amount of phosphorus accumulating microbial of bacteria in flocculent sludge were much more than that in the granules. It can be concluded that the flocculent sludge showed a better phosphorus removal.

  20. Efficacy and reliability of upgraded industrial treatment plant at Porto Marghera, near Venice, Italy, in removing nutrients and dangerous micropollutants from petrochemical wastewaters.

    Science.gov (United States)

    Verlicchi, Paola; Cattaneo, Serena; Marciano, Ferdinando; Masotti, Luigi; Vecchiato, Giuseppe; Zaffaroni, Carlo

    2011-08-01

    Chemical and petrochemical wastewaters contain a host of contaminants that require different treatment strategies. Regulation of macropollutants and micropollutants in the final discharge from industrial wastewater treatment plants (WWTPs) have become increasingly stringent in recent decades, requiring many WWTPs to be upgraded. This article presents an analysis of a WWTP treating petrochemicals in Porto Marghera, Italy, that recently was upgraded following legislative changes. Because of strict legal limits for macropollutants and micropollutants and a lack of space necessary for a full-scale WWTP overhaul, the existing activated sludge tank was converted into a membrane biological reactor. The paper presents experimental data collected during a five-month investigation showing the removal rates achieved by the upgraded plant for macropollutants (particularly nitrogen compounds) and micropollutants (heavy metals and organic and inorganic toxic compounds). PMID:21905411

  1. The use of mathematical modeling and pilot plant testing to develop a new biological phosphorus and nitrogen removal process

    Energy Technology Data Exchange (ETDEWEB)

    Nolasco, D.A.; Daigger, G.T.; Stafford, D.R.; Kaupp, D.M.; Stephenson, J.P.

    1998-09-01

    A mechanistic mathematical model for carbon oxidation, nitrogen removal, and enhanced biological phosphorus removal was used to develop the Step Bio-P process, a new biological phosphorus and nitrogen removal process with a step-feed configuration. A 9,000-L pilot plant with diurnally varying influent process loading rates was operated to verify the model results and to optimize the Step Bio-P process for application at the lethbridge, Alberta, Canada, wastewater treatment plant. The pilot plant was operated for 10 months. An automatic on-line data acquisition system with multiple sampling and metering points for dissolved oxygen, mixed liquor suspended solids, ammonia-nitrogen, nitrate-nitrogen, ortho-phosphate, and flow rates was used. A sampling program to obtain off-line data was carried out to verify the information from the on-line system and monitor additional parameters. The on-line and off-line data were used to recalibrate the model, which was used as an experimental design and process optimization tool.

  2. Inhibitory Effects of Silver Nanoparticles on Removal of Organic Pollutants and Sulfate in an Anaerobic Biological Wastewater Treatment Process.

    Science.gov (United States)

    Rasool, Kashif; Lee, Dae Sung

    2016-05-01

    The increasing use of silver nanoparticles (AgNPs) in commercial products and industrial processes raises issues regarding the toxicity of sludge biomass in biological wastewater treatment plants, due to potential antimicrobial properties. This study investigated the effects of AgNPs on removal of organic pollutants and sulfate in an anaerobic biological sulfate reduction process. At AgNPs concentrations of up to 10 mg/L, no significant inhibition of sulfate and COD removal was observed. However, at higher concentrations (50-200 mg/L) sulfate and COD removal efficiencies were significantly decreased to 51.8% and 33.6%, respectively. Sulfate and COD reduction followed first-order kinetics at AgNPs concentrations of up to 10 mg/L and second-order kinetics at AgNPs concentrations of 50-200 mg/L. Lactate dehydrogenase release profiles showed increases in cytotoxicity at AgNPs concentrations greater than 50 mg/L suggesting cell membrane disruption. Analysis of extracellular polymeric substances (EPS) from sulfidogenic sludge biomass and of Fourier transform infrared (FT-IR) spectra showed a decrease in concentrations of carbohydrates, proteins, humic substances, and lipids in the presence of AgNPs. Moreover, the interaction of AgNPs with sludge biomass and the damage caused to cell walls were confirmed through scanning electron microscopy with energy dispersive X-ray spectroscopy. PMID:27483773

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

    OpenAIRE

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

    2013-01-01

    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 photosynthesi...

  4. Atmospheric deposition impacts on nutrients and biological budgets of the Mediterranean Sea, results from the high resolution coupled model NEMOMED12/PISCES

    Science.gov (United States)

    Richon, Camille; Dutay, Jean-Claude; Dulac, François; Desboeufs, Karine; Nabat, Pierre; Guieu, Cécile; Aumont, Olivier; Palmieri, Julien

    2016-04-01

    Atmospheric deposition is at present not included in regional oceanic biogeochemical models of the Mediterranean Sea, whereas, along with river inputs, it represents a significant source of nutrients at the basin scale, especially through intense desert dust events. Moreover, observations (e.g. DUNE campaign, Guieu et al. 2010) show that these events significantly modify the biogeochemistry of the oligotrophic Mediterranean Sea. We use a high resolution (1/12°) version of the 3D coupled model NEMOMED12/PISCES to investigate the effects of high resolution atmospheric dust deposition forcings on the biogeochemistry of the Mediterranean basin. The biogeochemical model PISCES represents the evolution of 24 prognostic tracers including five nutrients (nitrate, ammonium, phosphate, silicate and iron) and two phytoplankton and zooplanktons groups (Palmiéri, 2014). From decadal simulations (1982-2012) we evaluate the influence of natural dust and anthropogenic nitrogen deposition on the budget of nutrients in the basin and its impact on the biogeochemistry (primary production, plankton distributions...). Our results show that natural dust deposition accounts for 15% of global PO4 budget and that it influences primarily the southern part of the basin. Anthropogenic nitrogen accounts for 50% of bioavailable N supply for the northern part. Deposition events significantly affect biological production; primary productivity enhancement can be as high as 30% in the areas of high deposition, especially during the stratified period. Further developments of the model will include 0D and 1D modeling of bacteria in the frame of the PEACETIME project.

  5. Pharmacia and biological functionalities of nutrient broth dispersed multi-walled carbon nanotubes:A novel drug delivery system

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new drug delivery system was developed using the interaction of nutrient broth treated multi-walled carbon nanotubes(NBT-MWCNTs) and cefotaxime sodium(CTX) as a model.Investigated factors of the drug delivery system include dispersion effect,biocompatibility of NBT-MWCNTs,pharmacodynamic effect and delivery efficiency in vitro.It was found that MWCNTs can be well dispersed in the nutrient broth and stable at least for one week at 4 °C.The formed NBT-MWCNTs suspension scarcely exhibits toxicity to E.coli at concentrations lower than 10.24 μg/mL,but displays enhanced pharmacodynamic effect of CTX via its bridge effect and targeted transport.Compared with general acid treated MWCNTs(AT-MWCNTs),our present NBT-MWCNTs show good biocompatibility,enhanced pharmacodynamic effect,and high delivery efficiency.

  6. Occurrence of xenobiotics in gray water and removal in three biological treatment systems

    NARCIS (Netherlands)

    Hernandez Leal, L.; Vieno, N.; Temmink, B.G.; Zeeman, G.; Buisman, C.J.N.

    2010-01-01

    Eighteen selected xenobiotics related to personal care and household chemicals (UV-filters, fragrances, preservatives, biocides, surfactants) were measured in gray water from 32 houses and in effluents of three different biological treatment systems (aerobic, anaerobic, and combined anaerobic + aero

  7. Effect of carbon sources on biological nitrogen and phosphorus removal in the municipal wastewater treatment system%碳源对污水处理系统脱氮除磷的影响

    Institute of Scientific and Technical Information of China (English)

    林雨倩; 赵军

    2014-01-01

    The performance of biological nutrient removal (BNR) processes is directly connected to the availability of carbon sources. This study introduces the metabolism mechanisms of carbon sources in each step of biological nitrogen and phosphorus removal processes, and the types and concentrations of carbon sources on the nitrogen and phosphorus removal are also discussed. It was revealed that the effective use of organic substrate including external and internal carbon sources could enhance the purifying performance of the system.%在污水强化生物脱氮除磷系统中,碳源种类及浓度对于处理系统去除效果的高效运行起到重要的作用。通过介绍生物脱氮及除磷各步骤碳源需求的机理,探讨碳源类型及碳源浓度对系统脱氮除磷效果的影响,同时对提高污水碳源浓度常用的手段即增加外碳源及内碳源方法进行分析。

  8. Dynamics of the biological properties of soil and the nutrient release of Amorpha fruticosa L. litter in soil polluted by crude oil.

    Science.gov (United States)

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

    2015-11-01

    Litter from Amorpha fruticosa, a potential phytoremediating plant, was collected and used in a decomposition experiment that involved the litterbag in soil polluted by crude oil. The dynamics of the biological properties of soil and the nutrient release of the litter were detected. The results indicated that (1) in lightly polluted soil (LP, petroleum concentration was 15 g kg(-1)), the bacteria (including actinomycetes), and fungi populations were significant higher than those in unpolluted soil (CK) at the 1st month after pollution, and the bacteria (including actinomycetes) populations were higher than those in the CK at the 6th and 12th months. In moderately polluted soil (MP, 30 g kg(-1)), the bacteria (including actinomycetes) populations were higher than those in the CK at the 1st and 6th months, whereas only the actinomycetes population was greater than that in the CK at the 12th month. In seriously polluted soil (SP, 45 g kg(-1)), only the fungi population was higher than that in the CK at the 6th month. (2) The activities of soil protease, carboxymethyl cellulase, and sucrase were generally inhibited in polluted soil. Peroxidase activity was generally inhibited in the LP and MP soil, and polyphenol oxidase activity was inhibited in the SP soil at 6-12 months. (3) At the end of litter decomposition, the LP soil significantly increased the release rate of all nutrients, except for K. The MP soil reduced the release rate of Fe and Mn, whereas it increased that of C and Cu. The SP soil decreased the release rate of all nutrients except for Cu and Zn. In conclusion, SP by crude oil would lead to limitations in the release of nutrients from the litter and to decreases in the community stability of a phytoremediating plant. A. fruticosa could only be used in phytoremediation of polluted soil at concentrations below 45 g kg(-1) (crude). PMID:26087933

  9. Using metagenomics and metatranscriptomics to study specific bacterial species involved in biological phosphorus removal from wastewater

    DEFF Research Database (Denmark)

    Albertsen, Mads; McIlroy, Simon Jon; Stokholm-Bjerregaard, Mikkel;

    to enrich for bacteria contributing to phosphorus removal and their normal competitors. To extract complete genomes we generated two metagenomes from each reactor, taken approximately 1 month apart, using the Illumina HiSeq2000 platform. Due to low micro-diversity in the reactors (2-15 dominating species...

  10. Control of a Biological Nitrogen Removal Process in an Intensified Single Reactor Configuration

    DEFF Research Database (Denmark)

    Vangsgaard, Anna Katrine; Mauricio Iglesias, Miguel; Gernaey, Krist;

    2013-01-01

    The nitrogen removing granular sludge process is a novel and intensified process. However, its stable operation and control remains a challenging problem. In this contribution, a new process oriented approach is used to develop, evaluate and benchmark control strategies to ensure stable operation...

  11. Effect of Return Sludge Pre-concentration on Biological Phosphorus Removal in a Novel Oxidation Ditch

    Institute of Scientific and Technical Information of China (English)

    刘巍; 扬殿海; 徐立; 贾川; 卢文建; BOSIRE Omosa Isaiah; 沈昌明

    2012-01-01

    A pilot-scale,pre-anoxic-anaerobic oxidation ditch was used in this study to treat municipal wastewater with limited carbon source.A novel return activated sludge(RAS) pre-concentration tank was adopted for improv-ing the phosphorus removal efficiency and the effects of RAS pre-concentration ratio were studied.Under the opti-mal operational condition,the suspended total phosphorus(STP) and the total phosphorus(TP) removal efficiencies were around 58.9% and 63.9% respectively and the effluent-P was lower than 0.8 mg·L-1.The reason is that with the optimal RAS pre-concentration ratio,nitrate is completely removed with endogenous carbon source and the secondary phosphorus release is strictly restrained in the pre-anoxic tank.Therefore,the anaerobic phosphorus release and the carbon source uptake by phosphorus accumulation organisms(PAOs) in the sludge,which are ex-tremely important to the phosphorus removal process,can be fully satisfied.Furthermore,the oxidation-reduction potential is proved to be suitable for controlling the RAS pre-concentration ratio due to influent fluctuation and varied conditions.The novel modified system is also beneficial for PAO accumulation.

  12. Removal of pharmaceuticals in biologically treated wastewater by chlorine dioxide or peracetic acid

    DEFF Research Database (Denmark)

    Hey, G.; Ledin, Anna; La Cour Jansen, Jes;

    2012-01-01

    l and clofibric acid, a metabol i te of clofibrate) were used as target substances at 40 (g/L ini tial concentration. Three di fferent wastewaters types originating from two WWTPs were used. One wastewater was col lected after extended ni trogen removal in activated sludge, one after treatment wi th...

  13. Combined ion exchange/biological denitrification for nitrate removal from ground water.

    NARCIS (Netherlands)

    Hoek, van der J.P.

    1988-01-01

    This thesis deals with the development of a new process for nitrate removal from ground water. High nitrate concentrations in ground water are a result of fertilization in agriculture. According to a directive of the European Community the maximum admissible concentration of nitrate in drinking wate

  14. Removal of the antiviral agent oseltamivir and its biological activity by oxidative processes

    International Nuclear Information System (INIS)

    The antiviral agent oseltamivir acid (OA, the active metabolite of Tamiflu®) may occur at high concentrations in wastewater during pandemic influenza events. To eliminate OA and its antiviral activity from wastewater, ozonation and advanced oxidation processes were investigated. For circumneutral pH, kinetic measurements yielded second-order rate constants of 1.7 ± 0.1 × 105 and 4.7 ± 0.2 × 109 M−1 s−1 for the reaction of OA with ozone and hydroxyl radical, respectively. During the degradation of OA by both oxidants, the antiviral activity of the treated aqueous solutions was measured by inhibition of neuraminidase activity of two different viral strains. A transient, moderate (two-fold) increase in antiviral activity was observed in solutions treated up to a level of 50% OA transformation, while for higher degrees of transformation the activity corresponded to that caused exclusively by OA. OA was efficiently removed by ozonation in a wastewater treatment plant effluent, suggesting that ozonation can be applied to remove OA from wastewater. - Highlights: ► Oseltamivir acid (OA) is oxidized by ozone and hydroxyl radical. ► Kinetics: We determined rate constants for the reaction with these oxidants. ► The specific activity of OA as neuraminidase inhibitor disappeared during oxidation. ► Ozonation and advanced oxidation can effectively remove OA from wastewaters. - Ozone and hydroxyl radical treatment processes can degrade aqueous oseltamivir acid and remove its antiviral activity.

  15. Startup and long term operation of enhanced biological phosphorus removal in continuous-flow reactor with granules.

    Science.gov (United States)

    Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie

    2016-07-01

    The startup and long term operation of enhanced biological phosphorus removal (EBPR) in a continuous-flow reactor (CFR) with granules were investigated in this study. Through reducing the settling time from 9min to 3min gradually, the startup of EBPR in a CFR with granules was successfully realized in 16days. Under continuous-flow operation, the granules with good phosphorus and COD removal performance were stably operated for more than 6months. And the granules were characterized with particle size of around 960μm, loose structure and good settling ability. During the startup phase, polysaccharides (PS) was secreted excessively by microorganisms to resist the influence from the variation of operational mode. Results of relative quantitative PCR indicated that granules dominated by polyphosphate-accumulating organisms (PAOs) were easier accumulated in the CFR because more excellent settling ability was needed in the system. PMID:27085149

  16. Community proteogenomics highlights microbial strain-variant protein expression within activated sludge performing enhanced biological phosphorus removal.

    Energy Technology Data Exchange (ETDEWEB)

    Wilmes, P [University of California, Berkeley; Andersson, Anders F. [University of California, Berkeley; Lefsrud, Mark G [McGill University, Montreal, Quebec; Wexler, Margaret [University of East Anglia, Norwich, United Kingdom; Shah, Manesh B [ORNL; Zhang, B [Vanderbilt University; Hettich, Robert {Bob} L [ORNL; Bond, P. L. [University of Queensland, The, Brisbane, Queensland, Australia; Verberkmoes, Nathan C [ORNL; Banfield, Jillian F. [University of California, Berkeley

    2008-01-01

    Enhanced biological phosphorus removal (EBPR) selects for polyphosphate accumulating organisms to achieve phosphate removal from wastewater. We used highresolution community proteomics to identify key metabolic pathways in "Candidatus Accumulibacter phosphatis"-mediated EBPR and to evaluate the contributions of co- 5 existing strains within the dominant population. Results highlight the importance of denitrification, fatty acid cycling and the glyoxylate bypass in EBPR. Despite overall strong similarity in protein profiles under anaerobic and aerobic conditions, fatty acid degradation proteins were more abundant during the anaerobic phase. By comprehensive genome-wide alignment of orthologous proteins, we uncovered strong 10 functional partitioning for enzyme variants involved in both core-metabolism and EBPR-specific pathways among the dominant strains. These findings emphasize the importance of genetic diversity in maintaining the stable performance of EBPR systems and demonstrate the power of integrated cultivation-independent genomics and proteomics for analysis of complex biotechnological systems.

  17. Biological Removal of Ammonia from Contaminated Air Streams Using Biofiltration System

    Directory of Open Access Journals (Sweden)

    MR Shahmansouri, H Taghipour, B Bina, H Movahdian

    2005-04-01

    Full Text Available Ammonia is a colorless, toxic, reactive and corrosive gas with a sharp odor. It is irritating to the skin, eyes, nose, throat, and lungs. Ammonia gas occurs in the environment naturally and is emitted by many industries and, therefore, its control is essential. Biofiltration is a new emerging technology that is being used as a control procedure. This study evaluates the use of a mixture of compost, sludge, and pieces of PVC as biofilter media to remove ammonia gas. The study investigates the effects of parameters such as inlet concentration, accumulation time, and depth of filter media to evaluate the removal efficiency. A laboratory scale biofilter column was built and operated to investigate the removal of ammonia from a waste gas stream. The findings indicate that for inlet concentrations of 236 ppm, and ammonia loading of less than 9.86 g-NH3/m3.h at empty bed residence time of 1 min, an ammonia removal efficiency of more than 99.9% was obtained. The acclimation period of the bacteria was 10 days. The average pressure drop during measurement was 4.44 mm H2O. The study also revealed that for concentration levels of 99, 211, and 236 ppmv, biofilter media depths of 40, 80, and 120 cm will be required, respectively. The results obtained in this study indicate that the biofiltration system composed of compost in the mixture of sludge and smashed polyvinyl chloride as biofilter media is an efficient method for the removal of ammonia from waste gas streams. It is also found that the optimum depth of biofilter media depends on the inlet concentration of ammonia.

  18. Modeling Nitrous Oxide Production during Biological Nitrogen Removal via Nitrification and Denitrification: Extensions to the General ASM Models

    DEFF Research Database (Denmark)

    Ni, Bing-Jie; Ruscalleda, Maël; Pellicer i Nàcher, Carles;

    2011-01-01

    Nitrous oxide (N2O) can be formed during biological nitrogen (N) removal processes. In this work, a mathematical model is developed that describes N2O production and consumption during activated sludge nitrification and denitrification. The well-known ASM process models are extended to capture N2O...... the four denitrification steps, the last one (N2O reduction to N2) seems to be inhibited first when O2 is present. Overall, N2O production can account for 0.1–25% of the consumed N in different nitrification and denitrification systems, which can be well simulated by the proposed model. In conclusion, we...

  19. Nutrient Driven Topology Optimization

    OpenAIRE

    Satha, Ganarupan

    2010-01-01

    The aim of this thesis is to investigate how a biological structure changes its shape and boundary under different cases of load if flow of nutrients is included, since nutrient flow has not been taken into account in previous studies. In order to simulate such a scenario we construct a model by using topology optimization (the SIMP model) and a balance law which is suitable for biological structures. Moreover, the model is derived by using an analogy with the dissipation inequality and Colem...

  20. Algal remediation of CO₂ and nutrient discharges: A review.

    Science.gov (United States)

    Judd, Simon; van den Broeke, Leo J P; Shurair, Mohamed; Kuti, Yussuf; Znad, Hussein

    2015-12-15

    The recent literature pertaining to the application of algal photobioreactors (PBRs) to both carbon dioxide mitigation and nutrient abatement is reviewed and the reported data analysed. The review appraises the influence of key system parameters on performance with reference to (a) the absorption and biological fixation of CO2 from gaseous effluent streams, and (b) the removal of nutrients from wastewaters. Key parameters appraised individually with reference to CO2 removal comprise algal speciation, light intensity, mass transfer, gas and hydraulic residence time, pollutant (CO2 and nutrient) loading, biochemical and chemical stoichiometry (including pH), and temperature. Nutrient removal has been assessed with reference to hydraulic residence time and reactor configuration, along with C:nutrient ratios and other factors affecting carbon fixation, and outcomes compared with those reported for classical biological nutrient removal (BNR). Outcomes of the review indicate there has been a disproportionate increase in algal PBR research outputs over the past 5-8 years, with a significant number of studies based on small, bench-scale systems. The quantitative impacts of light intensity and loading on CO2 uptake are highly dependent on the algal species, and also affected by solution chemical conditions such as temperature and pH. Calculations based on available data for biomass growth rates indicate that a reactor CO2 residence time of around 4 h is required for significant CO2 removal. Nutrient removal data indicate residence times of 2-5 days are required for significant nutrient removal, compared with high rate algal pond, HRAP) means that its footprint is at least two orders of magnitude greater than a classical BNR plant. It is concluded that the combined carbon capture/nutrient removal process relies on optimisation of a number of process parameters acting synergistically, principally microalgal strain, C:N:P load and balance, CO2 and liquid residence time, light

  1. Physical, Chemical, and Biological Methods for the Removal of Arsenic Compounds

    Directory of Open Access Journals (Sweden)

    K. T. Lim

    2014-01-01

    Full Text Available Arsenic is a toxic metalloid which is widely distributed in nature. It is normally present as arsenate under oxic conditions while arsenite is predominant under reducing condition. The major discharges of arsenic in the environment are mainly due to natural sources such as aquifers and anthropogenic sources. It is known that arsenite salts are more toxic than arsenate as it binds with vicinal thiols in pyruvate dehydrogenase while arsenate inhibits the oxidative phosphorylation process. The common mechanisms for arsenic detoxification are uptaken by phosphate transporters, aquaglyceroporins, and active extrusion system and reduced by arsenate reductases via dissimilatory reduction mechanism. Some species of autotrophic and heterotrophic microorganisms use arsenic oxyanions for their regeneration of energy. Certain species of microorganisms are able to use arsenate as their nutrient in respiratory process. Detoxification operons are a common form of arsenic resistance in microorganisms. Hence, the use of bioremediation could be an effective and economic way to reduce this pollutant from the environment.

  2. An examination of biological phosphorus removal using bacterial counting and poly-β-hydroxybutyrate analysis in batch and continuous flow systems

    OpenAIRE

    Hart, Vincent S

    1994-01-01

    The objective of this study was to examine excess biological phosphorus removing bacterial populations and their substrate utilization mechanisms. This study was a smaller part of a overall study of temperature effects upon excess biological phosphorus removal. Bacterial populations in both a continuous flow UCT (University of Cape Town) system and batch reactors were examined by direct counting using a well known staining procedure (Neisser staining), and a microscopic counting method dev...

  3. Mathematical Modeling and Evaluation of Ifas Wastewater Treatment Processes for Biological Nitrogen and Phosphorus Removal

    OpenAIRE

    Sriwiriyarat, Tongchai

    2002-01-01

    The hybrid activated sludge-biofilm system called Integrated Fixed Film Activated Sludge (IFAS) has recently become popular for enhanced nitrification and denitrification in aerobic zones because it is an alternative to increasing the volume of treatment plant units to accomplish year round nitrification and nitrogen removal. Biomass is retained on the fixed-film media and remains in the aerobic reactor, thus increasing the effective mean cell resident time (MCRT) of the biomass and providin...

  4. Biological removal of triphenylmethane dyes from aqueous solution by Lemna minor.

    Science.gov (United States)

    Török, Anamaria; Buta, Erzsébet; Indolean, Cerasella; Tonk, Szende; Silaghi-Dumitrescu, Luminita; Majdik, Cornelia

    2015-01-01

    The aim of this study is to investigate and develop a phytoremediation method for the removal of two triphenylmethane dyes (crystal violet and malachite green) using an aquatic plant, Lemna minor. The effects of operational parameters such as aquatic plant quantity, initial dye concentration, initial pH of the solutions and temperature of the medium were studied in order to determine the optimum phytoremediation conditions. The plant's photosynthetic pigments were determined quantitatively in order to detect the plant's response to abiotic stress. During the phytoremediation experiments the parallel sub-processes (phytosorption, phytoextraction, phytodegradation) were observed and analysed. The mechanisms of phytoremediation were studied using Fourier transformation infrared spectroscopy, ultraviolet-visible spectroscopy, thin layer chromatography and Energy-dispersive X-ray spectroscopy. Results show that the plant tolerated high concentrations (300 mg/L) of dyes, and was able to remove from the environment and accumulate in its cells the dyes up to a significant percentage (crystal violet was removed by about 80% and malachite green by 90%). PMID:26085430

  5. Biological sulfate removal from acrylic fiber manufacturing wastewater using a two-stage UASB reactor

    Institute of Scientific and Technical Information of China (English)

    Jin Li; Jun Wang; Zhaokun Luan; Zhongguang Ji; Lian Yu

    2012-01-01

    A two-stage UASB reactor was employed to remove sulfate from acrylic fiber manufacturing wastewater.Mesophilic operation (35±0.5℃) was performed with hydraulic retention time (HRT) varied between 28 and 40 hr.Mixed liquor suspended solids (MLSS)in the reactor was maintained about 8000 mg/L.The results indicated that sulfate removal was enhanced with increasing the ratio of COD/SO42-.At low COD/SO42-,the growth of the sulfate-reducing bacteria (SRB) was carbon-limited.The optimal sulfate removal efficiencies were 75% when the HRT was no less than 38 hr.Sulfidogenesis mainly happened in the sulfate-reducing stage,while methanogenesis in the methane-producing stage.Microbes in sulfate-reducing stage performed granulation better than that in methaneproducing stage.Higher extracellular polymeric substances (EPS) content in sulfate-reducing stage helped to adhere and connect the flocculent sludge particles together.SRB accounted for about 31% both in sulfate-reducing stage and methane-producing stage at COD/SO42- ratio of 0.5,while it dropped dramatically from 34% in sulfate-reducing stage to 10% in methane-producing stage corresponding to the COD/SO42- ratio of 4.7.SRB and MPA were predominant in sulfate-reducing stage and methane-producing stage respectively.

  6. Optimization of electrochemical reaction for nitrogen removal from biological secondary-treated milking centre wastewater.

    Science.gov (United States)

    Won, Seung-Gun; Jeon, Dae-Yong; Rahman, Md Mukhlesur; Kwag, Jung-Hoon; Ra, Chang-Six

    2016-01-01

    In order to remove the residual nitrogen from the secondary-treated milking centre wastewater, the electrochemical reaction including NH4-N oxidation and NOx-N reduction has been known as a relatively simple technique. Through the present study, the electrochemical reactor using the Ti-coated IrO2 anode and stainless steel cathode was optimized for practical use on farm. The key operational parameters [electrode area (EA) (cm(2)/L), current density (CD) (A/cm(2)), electrolyte concentration (EC) (mg/L as NaCl), and reaction time (RT) (min)] were selected and their effects were evaluated using response surface methodology for the responses of nitrogen and colour removal efficiencies, and power consumption. The experimental design was followed for the central composite design as a fractional factorial design. As a result of the analysis of variance, the p-values of the second-order polynomial models for three responses were significantly fit to the empirical values. The nitrogen removal was significantly influenced by CD, EC, and RT (p NaCl; RT, 240 min] was revealed as an optimal operational condition. The investigation on cathodic reduction of NOx-N may be required with respect to nitrite and nitrate separately as a future work. PMID:26582173

  7. Biological removal of gaseous ammonia in biofilters: space travel and earth-based applications

    Science.gov (United States)

    Joshi, J. A.; Hogan, J. A.; Cowan, R. M.; Strom, P. F.; Finstein, M. S.; Janes, H. W. (Principal Investigator)

    2000-01-01

    Gaseous NH3 removal was studied in laboratory-scale biofilters (14-L reactor volume) containing perlite inoculated with a nitrifying enrichment culture. These biofilters received 6 L/min of airflow with inlet NH3 concentrations of 20 or 50 ppm, and removed more than 99.99% of the NH3 for the period of operation (101, 102 days). Comparison between an active reactor and an autoclaved control indicated that NH3 removal resulted from nitrification directly, as well as from enhanced absorption resulting from acidity produced by nitrification. Spatial distribution studies (20 ppm only) after 8 days of operation showed that nearly 95% of the NH3 could be accounted for in the lower 25% of the biofilter matrix, proximate to the port of entry. Periodic analysis of the biofilter material (20 and 50 ppm) showed accumulation of the nitrification product NO3- early in the operation, but later both NO2- and NO3- accumulated. Additionally, the N-mass balance accountability dropped from near 100% early in the experiments to approximately 95 and 75% for the 20- and 50-ppm biofilters, respectively. A partial contributing factor to this drop in mass balance accountability was the production of NO and N2O, which were detected in the biofilter exhaust.

  8. Removal of polar UV stabilizers in biological wastewater treatments and ecotoxicological implications.

    Science.gov (United States)

    Molins-Delgado, Daniel; Díaz-Cruz, M Silvia; Barceló, Damià

    2015-01-01

    The present study describes the development, validation and application of a fully automated analytical method based on on-line solid-phase extraction-liquid chromatography-tandem mass spectrometry (on line SPE-HPLC-MS/MS) to assess the removal efficiency in water works and the ecotoxicological implications derived of the two most used benzotriazole-class UV stabilizers (BZTs), namely 1H-benzotriazole (BZT) and 5-methyl-1H-benzotriazole (MeBZT). Influent and effluent wastewater samples from 20 wastewater treatment plants (WWTPs) were analyzed. Removal rates (RE%) and half-lives (t1/2) for each BZTs were calculated and correlated to the hydraulic retention time (HRT) of each plant. Both BZTs were detected in all influent and effluent samples (concentrations in the range 26.7 ng L(-1)-42.9 μg L(-1)), with the highest concentrations corresponding to MeBZT. Results indicated that both compounds were recalcitrant (RE% in the range 11.8-94.7%) and that no clear influence of HRT on removals could be drawn. Finally, the potential environmental risk posed by the levels of BZTs detected was evaluated calculating the hazard quotients (HQs) MeBZT was the only BZTs posing a risk to Vibrio fischeri, Daphnia galeata and Pimephales promelas.

  9. Plants Responses to Nutrients Follow the Saturation Kinetic Typical of Enzyme Systems: Biological, Economical and Environmental Implications

    Directory of Open Access Journals (Sweden)

    R. P. Lana

    2008-01-01

    Full Text Available Agricultural efficiency has been associated with high plant productivity. However, it is dependent on fertilizers, which are nonrenewable resources. Crop production response to fertilizers is hyperbolic, following the Michaelis-Menten model and the law of diminishing return. Data of crop production (barley, bean, corn, cotton, soybean and wheat as a function of nitrogen, phosphorus, and potassium fertilization were analyzed by Lineweaver-Burk data transformation (L-B, that allows to calculate the amount of a specific nutrient needed to reach half (ks or other percentages of the theoretical maximum response (kmax and the efficiency of fertilizer use (kg of grain/kg of fertilizer. The efficiency of fertilizer use presented exponential decay by increasing fertilization: 55 to 3; 63 to 5; and 47 to 1 kg of corn/kg of fertilizer, by increasing nitrogen, P2O5 and potassium from 40 to 200; 40 to 200; and 60 to 300 kg ha-1, respectively. The L-B can be an alternative to the linear-plateau and polynomial regression methods of recommendation of plant fertilization, in which the fertilizers recommendation should be based on their efficiency of use, avoiding losses of nutrients, environmental pollution, waste of nonrenewable natural resources, and reducing productive costs.

  10. The acclimation of Chlorella to high-level nitrite for potential application in biological NOx removal from industrial flue gases.

    Science.gov (United States)

    Li, Tianpei; Xu, Gang; Rong, Junfeng; Chen, Hui; He, Chenliu; Giordano, Mario; Wang, Qiang

    2016-05-20

    Nitrogen oxides (NOx) are the components of fossil flue gas that give rise to the greatest environmental concerns. This study evaluated the ability of the green algae Chlorella to acclimate to high level of NOx and the potential utilization of Chlorella strains in biological NOx removal (DeNOx) from industrial flue gases. Fifteen Chlorella strains were subject to high-level of nitrite (HN, 176.5 mmolL(-1) nitrite) to simulate exposure to high NOx. These strains were subsequently divided into four groups with respect to their ability to tolerate nitrite (excellent, good, fair, and poor). One strain from each group was selected to evaluate their photosynthetic response to HN condition, and the nitrite adaptability of the four Chlorella strains were further identified by using chlorophyll fluorescence. The outcome of our experiments shows that, although high concentrations of nitrite overall negatively affect growth and photosynthesis of Chlorella strains, the degree of nitrite tolerance is a strain-specific feature. Some Chlorella strains have an appreciably higher ability to acclimate to high-level of nitrite. Acclimation is achieved through a three-step process of restrict, acclimate, and thriving. Notably, Chlorella sp. C2 was found to have a high tolerance and to rapidly acclimate to high concentrations of nitrite; it is therefore a promising candidate for microalgae-based biological NOx removal. PMID:27010349

  11. Biological responses of the coral Montastraea annularis to the removal of filamentous turf algae.

    Directory of Open Access Journals (Sweden)

    Neidy P Cetz-Navarro

    Full Text Available Coral reef degradation increases coral interactions with filamentous turf algae (FTA and macroalgae, which may result in chronic stress for the corals. We evaluated the effects of short (2.5 month and long (10 month periods of FTA removal on tissue thickness (TT, zooxanthellae density (ZD, mitotic index (MI, and concentration of chlorophyll a (Chl a in Montastraea annularis at the beginning and end of gametogenesis. Ramets (individual lobes within a colony consistently surrounded by FTA and ramets surrounded by crustose coralline algae (CCA were used as controls. FTA removal reduced coral stress, indicated by increased TT and ZD and lower MI. The measured effects were similar in magnitude for the short and long periods of algal removal. Ramets were more stressed at the end of gametogenesis compared with the beginning, with lower ZD and Chl a cm(-2, and higher MI. However, it was not possible to distinguish the stress caused by the presence of FTA from that caused by seasonal changes in seawater temperature. Ramets surrounded by CCA showed less stress in comparison with ramets surrounded by FTA: with higher TT, Chl a cm(-2 and ZD, and lower MI values. Coral responses indicated that ramets with FTA suffered the most deleterious effects and contrasted with those measured in ramets surrounded by CCA. According to published studies and our observations, there could be at least six mechanisms associated to FTA in the stress caused to M. annularis by FTA. Owing to the high cover of FTA (in contrast to macroalgae and CCA in the Caribbean, the chronic stress, the overgrowth and mortality that this functional algal group can cause on M. annularis species complex, a further decline of this important reef-building coral in the Caribbean is expected.

  12. Biological nitrate removal from water and wastewater by solid-phase denitrification process.

    Science.gov (United States)

    Wang, Jianlong; Chu, Libing

    2016-11-01

    Nitrate pollution in receiving waters has become a serious issue worldwide. Solid-phase denitrification process is an emerging technology, which has received increasing attention in recent years. It uses biodegradable polymers as both the carbon source and biofilm carrier for denitrifying microorganisms. A vast array of natural and synthetic biopolymers, including woodchips, sawdust, straw, cotton, maize cobs, seaweed, bark, polyhydroxyalkanoate (PHA), polycaprolactone (PCL), polybutylene succinate (PBS) and polylactic acid (PLA), have been widely used for denitrification due to their good performance, low cost and large available quantities. This paper presents an overview on the application of solid-phase denitrification in nitrate removal from drinking water, groundwater, aquaculture wastewater, the secondary effluent and wastewater with low C/N ratio. The types of solid carbon source, the influencing factors, the microbial community of biofilm attached on the biodegradable carriers, the potential adverse effect, and the cost of denitrification process are introduced and evaluated. Woodchips and polycaprolactone are the popular and competitive natural plant-like and synthetic biodegradable polymers used for denitrification, respectively. Most of the denitrifiers reported in solid-phase denitrification affiliated to the family Comamonadaceae in the class Betaproteobacteria. The members of genera Diaphorobacter, Acidovorax and Simplicispira were mostly reported. In future study, more attention should be paid to the simultaneous removal of nitrate and toxic organic contaminants such as pesticide and PPCPs by solid-phase denitrification, to the elucidation of the metabolic and regulatory relationship between decomposition of solid carbon source and denitrification, and to the post-treatment of the municipal secondary effluent. Solid-phase denitrification process is a promising technology for the removal of nitrate from water and wastewater. PMID:27396522

  13. Removal of priority and emerging substances by biological and tertiary treatments

    OpenAIRE

    Mailler, Romain; Gasperi, Johnny; Rocher, Vincent; Chebbo, Ghassan

    2013-01-01

    10 p. International audience My researches are divided in two principal parts. The first part concerns the fate of micropollutants in conventional wastewater treatment plants (WWTPs) composed by primary and biological treatments. Different studies have been held by OPUR research program on primary treatments, conventional activated sludge (CAS) and biofiltration (BF), the thesis will synthesize them and add data from measurement campaigns on industrial scale membrane bioreactor (MBR) un...

  14. Biological control of the removal of abiogenic particles from the surface ocean

    Science.gov (United States)

    Deuser, W.G.; Brewer, P.G.; Jickells, T.D.; Commeau, R.F.

    1983-01-01

    Concurrent measurements of particle concentrations in the near-surface water and of particle fluxes in the deep water of the Sargasso Sea show a close coupling between the two for biogenic components. The concentrations of suspended matter appear to follow an annual cycle similar to that of primary production and deepwater particle flux. Although the concentration of particulate aluminum in the surface water appears to vary randomly with respect to that cycle, the removal of aluminum to deep water is intimately linked to the rapid downward transport of organic matter.

  15. Biological technologies for the removal of sulfur containing compounds from waste streams: bioreactors and microbial characteristics.

    Science.gov (United States)

    Li, Lin; Zhang, Jingying; Lin, Jian; Liu, Junxin

    2015-10-01

    Waste gases containing sulfur compounds, such as hydrogen sulfide, sulfur dioxide, thioethers, and mercaptan, produced and emitted from industrial processes, wastewater treatment, and landfill waste may cause undesirable issues in adjacent areas and contribute to atmospheric pollution. Their control has been an area of concern and research for many years. As alternative to conventional physicochemical air pollution control technologies, biological treatment processes which can transform sulfur compounds to harmless products by microbial activity, have gained in popularity due to their efficiency, cost-effectiveness and environmental acceptability. This paper provides an overview of the current biological techniques used for the treatment of air streams contaminated with sulfur compounds as well as the advances made in the past year. The discussion focuses on bioreactor configuration and design, mechanism of operation, insights into the overall biological treatment process, and the characterization of the microbial species present in bioreactors, their populations and their interactions with the environment. Some bioreactor case studies are also introduced. Finally, the perspectives on future research and development needs in this research area were also highlighted. PMID:26250546

  16. Biological technologies for the removal of sulfur containing compounds from waste streams: bioreactors and microbial characteristics.

    Science.gov (United States)

    Li, Lin; Zhang, Jingying; Lin, Jian; Liu, Junxin

    2015-10-01

    Waste gases containing sulfur compounds, such as hydrogen sulfide, sulfur dioxide, thioethers, and mercaptan, produced and emitted from industrial processes, wastewater treatment, and landfill waste may cause undesirable issues in adjacent areas and contribute to atmospheric pollution. Their control has been an area of concern and research for many years. As alternative to conventional physicochemical air pollution control technologies, biological treatment processes which can transform sulfur compounds to harmless products by microbial activity, have gained in popularity due to their efficiency, cost-effectiveness and environmental acceptability. This paper provides an overview of the current biological techniques used for the treatment of air streams contaminated with sulfur compounds as well as the advances made in the past year. The discussion focuses on bioreactor configuration and design, mechanism of operation, insights into the overall biological treatment process, and the characterization of the microbial species present in bioreactors, their populations and their interactions with the environment. Some bioreactor case studies are also introduced. Finally, the perspectives on future research and development needs in this research area were also highlighted.

  17. Ozone-biological activated carbon integrated treatment for removal of precursors of halogenated nitrogenous disinfection by-products.

    Science.gov (United States)

    Chu, Wenhai; Gao, Naiyun; Yin, Daqiang; Deng, Yang; Templeton, Michael R

    2012-03-01

    Pilot-scale tests were performed to reduce the formation of several nitrogenous and carbonaceous disinfection by-products (DBPs) with an integrated ozone and biological activated carbon (O(3)-BAC) treatment process following conventional water treatment processes (coagulation-sedimentation-filtration). Relative to the conventional processes alone, O(3)-BAC significantly improved the removal of turbidity, dissolved organic carbon, UV(254), NH(4)(+) and dissolved organic nitrogen from 98-99%, 58-72%, 31-53%, 16-93% and 35-74%, respectively, and enhanced the removal efficiency of the precursors for the measured DBPs. The conventional process was almost ineffective in removing the precursors of trichloronitromethane (TCNM) and dichloroacetamide (DCAcAm). Ozonation could not substantially reduce the formation of DCAcAm, and actually increased the formation potential of TCNM; it chemically altered the molecular structures of the precursors and increased the biodegradability of N-containing organic compounds. Consequently, the subsequent BAC filtration substantially reduced the formation of the both TCNM and DCAcAm, thus highlighting a synergistic effect of O(3) and BAC. Additionally, O(3)-BAC was effective at controlling the formation of the total organic halogen, which can be considered as an indicator of the formation of unidentified DBPs.

  18. Enhanced nitrogen removal in a wastewater treatment process characterized by carbon source manipulation with biological adsorption and sludge hydrolysis.

    Science.gov (United States)

    Liu, Hongbo; Zhao, Fang; Mao, Boyang; Wen, Xianghua

    2012-06-01

    An innovative adsorption/nitrification/denitrification/sludge-hydrolysis wastewater treatment process (ENRS) characterized by carbon source manipulation with a biological adsorption unit and a sludge hydrolysis unit was developed to enhance nitrogen removal and reduce sludge production for municipal wastewater treatment. The system presented good performance in pollutants removal, yielding the effluent with average COD, NH(4)(+)-N, TN and TP of 48.5, 0.6, 13.2 and 1.0 mg/L, respectively. Sixty percent of the total carbon source in the influent was concentrated and separated by the quick adsorption of activated sludge, providing the possibilities of reusing waste carbon source in the denitrification tank and accumulating nitrobacteria in the nitrification tank. Low temperature of 6-15 °C and high hydraulic loading rate of 3.0-15.0 m(3)/d did not affect NH(4)(+)-N removal performance, yielding the NH(4)(+)-N of lower 1.0 mg/L in the effluent. Furthermore, 50% of the residual sludge in the ENRS system could be transformed into soluble COD (SCOD) by alkaline thermal hydrolysis with temperature of 60 °C and pH of 11, and the hydrolyzed carbon could completely substitute methanol as a good quality carbon to support high efficient denitrification.

  19. Effect of Ferric Chloride on the Properties of Biological Sludge in Co-precipitation Phosphorus Removal Process

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhibin; LI Yi; WEI Leilei; L(U) Yufeng; WANG Meng; GAO Baoyu

    2013-01-01

    This paper studied the effect of ferric chloride on waste sludge digestion,dewatering and sedimentation under the optimized doses in co-precipitation phosphorus removal process.The experimental results showed that the concentration of mixed liquid suspended solid (MLSS) was 2436 mg·L-1 and 2385 mg·L-1 in co-precipitation phosphorus removal process (CPR) and biological phosphorous removal process (BPR),respectively.The sludge reduction ratio for each process was 22.6% and 24.6% in aerobic digestion,and 27.6% and 29.9% in anaerobic digestion,respectively.Due to the addition of chemical to the end of aeration tank,the sludge content of CPR was slightly higher than that of BPR,but the sludge reduction rate for both processes had no distinct difference.The sludge volume index (SVI) and sludge specific resistance of BPR were 126 ml·g-1 and 11.7×1012 m·kg-1,respectively,while those of CPR were only 98 ml·g-1 and 7.1×1012 m·kg-1,indicating that CPR chemical could improve sludge settling and dewatering.

  20. 污废水生物脱氮除磷技术研究进展%Research Status of Technologies for Nitrogen and Phosphorus Removal by Biological Processes

    Institute of Scientific and Technical Information of China (English)

    刘启承

    2013-01-01

      总结了目前城市污水生物脱氮除磷技术研究及应用进展,分析了脱氮除磷工艺机理及其特点,探讨了城市污水生物脱氮除磷工艺深入研究的方向。%This paper reviews the advances in the biological nitrogen and phosphorus removal technologies for municipal wastewater .The mechanism and characteristics of nitrogen and phosphorus removal processes are analyzed , and directions of studying the biological nitrogen and phosphorus removal technologies are also discussed .

  1. Biological hydrogen production: Simultaneous saccharification and fermentation with nitrogen and phosphorus removal from wastewater effluent

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, Steve; Dixon, Melissa [U.S. Army Edgewood Chemical Biological Center, 5183 Blackhawk Road Building E3160, Aberdeen Proving Ground, MD 21010-5424 (United States)

    2010-09-15

    A simple anaerobic biodegradation process using wastewater treatment plant (WWTP) effluent, shredded paper, and a purge of nitrogen gas was used to produce hydrogen and simultaneously capture nitrogen and phosphorus. Two reactor configurations, a sequencing batch reactor (SBR) and a classic batch reactor (CBR) were tested as simultaneous saccharification and fermentation reactors (enzymatic hydrolysis and fermentation in one tank). The CBR demonstrated greater stability of hydrogen production and simplicity of operation, while the SBR provided better nitrogen and phosphorus removal efficiencies. Nuclear magnetic resonance analyses showed acetic acid to be the main product from both reactors. Optimal CBR conditions were found to be pH 5, 4 g/L loading, 0.45 ml/g Accellerase 1500, and 38 C. Experiments with an argon purge in place of nitrogen and with ammonium chloride spiking suggested that hydrogenase and nitrogenase enzymes contributed similarly to hydrogen production in the cultures. Analysis of a single fermentation showed that hydrogen production occurred relatively early in the course of TOC removal, and that follow-on treatments might extract more energy from the products. (author)

  2. Kinetics of organic removal in fixed-bed aerobic biological reactor.

    Science.gov (United States)

    Borghei, S M; Sharbatmaleki, M; Pourrezaie, P; Borghei, G

    2008-03-01

    The process kinetics of a lab-scale upflow aerobic immobilized biomass (UAIB) reactor using simulated sugar-manufacturing wastewater as feed was investigated. The experimental unit consisted of a 22l reactor filled with high porosity pumice stone. The UAIB reactor was tested under different organic loads and different hydraulic retention times (HRT) and the substrate loading removal rate was compared with prediction of Stover-Kincannon model, second-order model and the first order substrate removal model. After obtaining steady-state conditions, organic loading rate was increased from 750 to 4500 g COD/m(3) day to resemble wastewater from sugar production lines, and hydraulic retention time was decreased from 1 to 0.5 days, stepwise. Nine different operational conditions were applied changing these two parameters in a certain program. As a result of the calculations, Stover-Kincannon model and second-order model known as "Grau" model were found to be the most appropriate models for this reactor. Stover-Kincannon model and Grau second-order model gave high correlation coefficients, which were 99.7% and 99.4%, respectively. Therefore, these models could be used in predicting the behavior or design of the UAIB reactors.

  3. Removal of the antiviral agent oseltamivir and its biological activity by oxidative processes.

    Science.gov (United States)

    Mestankova, Hana; Schirmer, Kristin; Escher, Beate I; von Gunten, Urs; Canonica, Silvio

    2012-02-01

    The antiviral agent oseltamivir acid (OA, the active metabolite of Tamiflu(®)) may occur at high concentrations in wastewater during pandemic influenza events. To eliminate OA and its antiviral activity from wastewater, ozonation and advanced oxidation processes were investigated. For circumneutral pH, kinetic measurements yielded second-order rate constants of 1.7 ± 0.1 × 10(5) and 4.7 ± 0.2 × 10(9) M(-1) s(-1) for the reaction of OA with ozone and hydroxyl radical, respectively. During the degradation of OA by both oxidants, the antiviral activity of the treated aqueous solutions was measured by inhibition of neuraminidase activity of two different viral strains. A transient, moderate (two-fold) increase in antiviral activity was observed in solutions treated up to a level of 50% OA transformation, while for higher degrees of transformation the activity corresponded to that caused exclusively by OA. OA was efficiently removed by ozonation in a wastewater treatment plant effluent, suggesting that ozonation can be applied to remove OA from wastewater. PMID:22230064

  4. ENGINEERING SOLUTION OF BIOLOGICAL TREATMENT COMPLEX WITH NUTRIENT REMOVAL BASED ON SIMULATION MODELING / ИНЖЕНЕРНОЕ РЕШЕНИЕ КОМПЛЕКСА БИОЛОГИЧЕСКОЙ ОЧИСТКИ ОТ БИОГЕННЫХ ЭЛЕМЕНТОВ НА ОСНОВЕ ИМИТАЦИОННОГО МОДЕЛИРОВАНИЯ

    Directory of Open Access Journals (Sweden)

    Bazhenov V. I. / Баженов Виктор Иванович

    2014-12-01

    Full Text Available The paper provides a mechanism for the biological purification of wastewater in the aeration tanks with nutrient removal in connection with simulation modeling, based on software GPS-X. The authors provide the example of zones design optimization for denitrification process MUCT achieved when N-NO3 = 0.3 mg/L. Presented is the typical block for biological treatment with nitrogen and phosphorus removal with flowrate 1140 m3/h due to one section of the aeration tank / Приводится механизм биологической очистки сточных вод в аэротенках с удалением биогенных элементов в связи с имитационным моделированием на базе расчетного комплекса GPS-X. Рассмотрен пример оптимизации размеров зоны денитрификации для процесса MUCT, достигнутом при N-NO3 = 0,3 мг/л. Представлен типовой проект блока биологической очистки с удалением азота и фосфора при расходе на одну секцию аэротенка 1140 м3/ч

  5. Carbon removal and nitrification in a rotating biological contractor under different steady-state conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lowhorn, R.W. (Ben Cor Construction Co., Chattanooga, TN); Bustamante, R.B.; Bonner, W.P.

    1980-01-01

    The stage-by-stage degradation of soluble organics was monitored during waste water treatment. The effects of process parameters on nitration of waste water were determined. The rotating biological contactor, applying the fixed film prinicple, was used in this study. Parameters affecting nitrifying bacteria are: dissolved oxygen, temperature, pH, ammonia, nitrite, mean-cell retention time, organic matter, alkalinity, and rotational speed. It was shown that an increase in chemical oxygen demand can occur in the stages following heterotrophic activity in an RBC unit as a result of inadequate buffering capacity in waste water. (DMC)

  6. BIOLOGICAL NITROGEN REMOVAL FROM WASTEWATER BY DENITRIFICATION OF MIX-CULTURING FUNGI AND BACTERIA

    Institute of Scientific and Technical Information of China (English)

    TAKAYA; Naoki; SHOUN; Hirofumi

    2006-01-01

    Denitrificationis a biological processin which nitrateand/or nitrite is reduced to gaseous nitrogen,dinitrogen(N2)or nitrous oxide(N2O)while carbon dioxide is thesecond gaseous product of the process.This is one of themain mechanisms of the global nitrogen cycle,and playsanimportant role as the reverse reaction of nitrogen fixa-tion in maintaining global environmental homeostasis[1].Denitrification has beenlongthought to be a unique char-acteristic of prokaryotes[2,3].Anumber of bacteria(suchasPseudomonas s...

  7. H2S gas biological removal efficiency and bacterial community diversity in biofilter treating wastewater odor.

    Science.gov (United States)

    Omri, Ilhem; Bouallagui, Hassib; Aouidi, Fathia; Godon, Jean-Jacques; Hamdi, Moktar

    2011-11-01

    The objective of this study was to assess the feasibility of using a biofilter system to treat hydrogen sulfide (H2S) contaminated air and to characterize its microbial community. The biofilter system was packed with peat. During the experimental work, the peat was divided in three layers (down, middle, and up). Satisfactory removal efficiencies of H2S were proved and reached 99% for the majority of the run time at an empty bed retention time (EBRT) of 60 s. The polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method was used to uncover the changes in the microbial community between the different layers. Analysis of SSCP profiles demonstrated significant differences in community structure from a layer to another with a strong decrease in species diversity towards the up layer. It was found that the used support was suitable for microorganism growth, and may have a potential application in H2S biofiltration system. PMID:21945209

  8. A Combined System for Biological Removal of Nitrogen and Carbon from Nylon-6 Production Wastewater

    Institute of Scientific and Technical Information of China (English)

    LIU Fang; LIU Guo-hua; TIAN Qing; ZHANG Man; CHEN Ji-hua

    2007-01-01

    A combined system consisting of hydrolysisacidification, denitrification and nitrification reactors wasused to remove carbon and nitrogen from the nylon - 6production wastewater, which was characterized by goodbiodegradability and high nitrogen concentration. Theinfluences of Chemical Oxygen Demand(COD) in theinfluent, recirculation ratio, Hydraulic Residence Time(HRT) and Dissolved Oxygen(DO) concentration on thesystem performances were investigated. From results itcould be seen that good performances have been achievedduring the overall experiments periods, and COD, TotalNitrogen(TN), NH+-N and Suspended Solids(SS) in theeffluent were 53, 16, 2 and 24 mg·L-1, respectively,which has satisfied the first standard of wastewaterdischarge established by Environmental Protection Agency(EPA) of China. Furthermore, results showed thatoperation factors, viz. COD in the influent, recirculationratio, HRT and DO concentration, all had importantinfluences on the system performances.

  9. Nitrate Removal from Wastewater through Biological Denitrification with OGA 24 in a Batch Reactor

    Directory of Open Access Journals (Sweden)

    Federico Rossi

    2014-12-01

    Full Text Available Nitrates pollution of waters is a worldwide problem and its remediation is a big challenge from the technical and the scientific point of view. One of the most used and promising cleaning techniques is the biological treatment of wastewaters operated by denitrifying bacteria. In this paper we begin a thorough study of denitrifying performances of the bacterium Azospira sp. OGA 24, recently isolated from the highly polluted Sarno river in the south of Italy. Here, the kinetics of nitrates consumption operated by bacteria in a specifically devised batch bioreactor, in anoxic condition and with acetate as the organic substrate, has been characterized. Experimental data were then used in a simplified model of a real wastewater treatment plant to find that OGA 24 can clean water with efficiency up to 90%. The denitrifying performances of OGA 24 match the requirements of Italian laws and make the bacterium suitable for its employment in treatment plants.

  10. Effects of male removal on female reproductive biology in Ross' and Lesser Snow Geese

    Science.gov (United States)

    Leschack, C.R.; Afton, A.D.; Alisauskas, R.T.

    1998-01-01

    We studied effects of mate removal on nesting and hatching success, incubation behavior, body mass, and post-hatch dispersal distance of female Ross' (Chen rossii) and Lesser Snow Geese (C. caerulescens caerulescens) at Karrak Lake. N.W.T., Canada. Male ge and widowed and paired control females were monitored through post-hatch dispersal. Nesting and hatching success did not differ between species or treatments (widowed vs paired) and averaged 77.5 ?? 3.8% and 64.0 ?? 3.6% (??SE), respectively. Paired females spent more time with their bills tucked (23.7 ?? 3.3% vs 9.1 ?? 4.0%) and less time alert (8.6 ?? 2.9% vs 22.9 ?? 3.5%) while on nests than did widowed females. Snow widowed females (31.1 ?? 4.7%) and Ross' widowed females (20.6 ?? 6.0%) generally spent more time each day in head-up alert than did Snow paired females (7.1 ?? 3.8%). Snow paired maleS (11.8 ?? 3.8%), Ross' paired females (9.4 ?? 3.6%), and Ross' paired males (7.9 ?? 3.6%). Body mass of paired and widowed female Ross' Geese did not differ at hatch or at time of post-hatch recapture; however, mean distance recaptured from the breeding colony was greater for paired (50.9 ?? 6.1 km) than for widowed females (27.3 ?? 6.6 km). Total mass gain (276 ?? 19 g) and rate of mass gain (8.4 ?? 0.5 g/day), from hatch until post-hatch recapture (33.1 ?? 1.2 days), were similar for widowed and paired female Ross' Geese. Male removal experiments in monogamous, precocial species generally have produced few effects on female nesting success or incubation behavior. We suggest that male parental care in arctic-nesting geese is more critical during laying and the post-hatch period than during incubation.

  11. The effect of COD loading on the granule-based enhanced biological phosphorus removal system and the recoverability.

    Science.gov (United States)

    Yu, Shenjing; Sun, Peide; Zheng, Wei; Chen, Lujun; Zheng, Xiongliu; Han, Jingyi; Yan, Tao

    2014-11-01

    In this study, the effect of varied COD loading (200, 400, 500, 600 and 800 mg L(-1)) on stability and recoverability of granule-based enhanced biological phosphorus removal (EBPR) system was investigated during continuously 53-d operation. Results showed that COD loading higher than 500 mg L(-1) could obviously deteriorate the granular EBPR system and result in sludge bulking with filamentous bacteria. High COD loading also changed the transformation patterns of poly-β-hydroxyalkanoates (PHAs) and glycogen in metabolism process of polyphosphate-accumulating organisms (PAOs) and inhibited the EPS secretion, which completely destroyed the stability and integrality of granules. Results of FISH indicated that glycogen-accumulating organisms (GAOs) and other microorganisms had a competitive advantage over PAOs with higher COD loading. The community composition and EBPR performance were recovered irreversibly in long time operation when COD loading was higher than 500 mg L(-1). PMID:25189512

  12. In situ identification of polyphosphate- and polyhydroxyalkanoate-accumulating traits for microbial populations in a biological phosphorus removal process

    DEFF Research Database (Denmark)

    Liu, W.-T.; Nielsen, Alex Toftgaard; Wu, JH;

    2001-01-01

    Polyphosphate- and polyhydroxyalkanoate (PHA)- accumulating traits of predominant microorganisms in an efficient enhanced biological phosphorus removal (EBPR) process were investigated systematically using a suite of non-culture-dependent methods. Results of 16S rDNA clone library and fluorescence......, electron microscopy with energy-dispersive X-ray analysis was used to validate the staining specificity of 4,6-diamino-2-phenylindole (DAPI) for intracellular polyphosphate and revealed the composition of polyphosphate granules accumulated in predominant bacteria as mostly P, Ca and Na. As a result, DAPI...... and PHA staining procedures could be combined with FISH to identify directly the polyphosphate- and PHA-accumulating traits of different phylogenetic groups. Members of Accumulibacter phosphatis and the novel gamma-proteobacterial group were observed to accumulate both polyphosphate and PHA. In addition...

  13. Effect of sludge retention time on continuous-flow system with enhanced biological phosphorus removal granules at different COD loading.

    Science.gov (United States)

    Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie

    2016-11-01

    The effect of sludge retention time (SRT) on the continuous-flow system with enhanced biological phosphorus removal (EBPR) granules at different COD loading was investigated during the operation of more than 220days. And the results showed that when the system operated at long SRT (30days) and low COD loading (200mg·L(-1)), it could maintain excellent performance. However, long SRT and high COD loading (300mg·L(-1)) deteriorated the settling ability of granules and the performance of system and resulted in the overgrowth of filamentous bacteria. Meanwhile, the transformation of poly-β-hydroxyalkanoates (PHAs) and glycogen in metabolism process was inhibited. Moreover, the results of pyrosequencing indicated that filamentous bacteria had a competitive advantage over polyphosphate-accumulating organisms (PAOs) at high COD loading and long SRT. The PAOs specious of Candidatus_Accumlibater and system performance increased obviously when the SRT was reduced to 20days at high COD loading. PMID:27472749

  14. Respirometry applied for biological nitrogen removal process; Aplicacion de la respirometria al tratamiento biologico para la eliminacion del nitrogeno

    Energy Technology Data Exchange (ETDEWEB)

    Serrano, E.

    2004-07-01

    In waste water treatment plants, the Biological Nitrogen Removal (BNR) has acquired a fundamental importance. The BNR processes are Nitrification ( aerobic) and Denitrification (anoxic). Since both processes are carried on living microorganisms, a lack of their bioactivity information might cause serious confusion about their control criteria and following up purposes. For this reason, the Re spirometry applied to those processes has reached an important role by getting an essential information in a timely manner through respiration rate measurements in static and dynamic modes and applications such as AUR (Ammonium Uptake Rate), Nitrification Capacity. RBCOD (Readily Biodegradable COD) as well as AUR related to SRT (Sludge age), RBCOD related to NUR (Specific Nitrate Uptake Rate) and others. By other side in this article we have introduced a not very well known applications related to denitrification, about the methanol acclimatization and generated bioactivity. (Author) 6 refs.

  15. Gamma rays as an effective tool for removing undesirable color without adverse changes in biological activities of red beet extracts

    Science.gov (United States)

    Lee, Seung Sik; Lee, Eun Mi; Hong, Sung Hyun; Bai, Hyoung-Woo; Lee, In Chul; Chung, Byung Yeoup

    2012-08-01

    The ethanolic extracts of red beet (Beta vulgaris L.) hairy root were used to investigate the removal of color and improvement of biological activity for enhanced industrial applications. The extracts were exposed to gamma rays ranging from 2.5 to 30 kGy. The red beet hairy root is composed of two major red-colorants, betanin and isobetanin. Gamma ray radiation at 5 kGy remarkably reduced the levels of the major colorants by 94% and the reddish color was eliminated by doses greater than 10 kGy. Color removal was likely due to the gamma ray radiolysis of ethanol. Although details on the mechanism responsible for the decay of the chromophore have not been entirely determined, our results suggest that the free radicals that are produced during this process are capable of destroying the chromophore group in isobetanin, thus bleaching the substrate solution. In spite of the degradation of the major colorants, the biological activities of constituents of the extract such as DPPH radical scavenging and tyrosinase inhibition were negligibly affected by the gamma ray radiation up to 20 kGy. The antioxidant activity was 92.7% in control samples and 90.0-92.0% in irradiated samples (2.5-20 kGy), and a slight decrease to 87.5% was observed for gamma ray radiation at 30 kGy. In addition, tyrosinase inhibition activity has also the same pattern; the activity is slightly increased from 50.7% of control to 49.1-52.8% of irradiated samples (2.5-20 kGy) with a 46.8% at 30 kGy.

  16. Nutrient recycling of sorghum straw and soil biological attributes in Eastern Amazon Reciclagem de nutrientes da palhada de sorgo e atributos biológicos do solo na Amazônia Oriental

    Directory of Open Access Journals (Sweden)

    Patrícia Ribeiro Maia

    2012-10-01

    Full Text Available The microbial biomass and activity are biological indicators sensitive to environmental changes caused by agricultural use and can provide important information for the planning of adequate land use. The objective of this research was to evaluate the nutrient recycling, persistence, and biological attributes of sorghum straw in Oxisol as a function of soil management systems. The experiment was carried out at the Federal Rural University of Amazonia in randomized block design with 3 x 2 factorial and four replicates. Three sorghum hybrids and two soil management systems were the factors used to assess straw decomposition. In order to evaluate the biological attributes, a 2 x 2 factorial experiment with four replicates was carried out using two soil management systems and two sampling dates. Total organic carbon (TOC, carbon in the soil microbial biomass (C-SMB, C-SMB/TOC ratio, basal respiration and metabolic quotient (qCO2 were investigated. The Qualimax hybrid presented the highest C/N ratio (55 and longer straw persistence in soil after 120 days of management (35%. The highest TOC, C-SMB, C-SMB/TOC ratio, and basal respiration and the smallest qCO2 were observed during the rainy season and in the no-till system.A atividade e biomassa microbiana são indicadores biológicos sensíveis a alterações ambientais decorrentes do uso agrícola, podendo fornecer informações importantes para o uso adequado do solo. Objetivou-se, com este trabalho, avaliar a ciclagem de nutrientes, atributos biológicos e a persistência da palhada de sorgo em um Latossolo Amarelo distrófico, em função de sistemas de manejo do solo. O experimento foi realizado na Universidade Federal Rural da Amazônia, em um delineamento em blocos casualizados, com fatorial 3 x 2 e quatro repetições. Os fatores foram: três híbridos de sorgo e dois sistemas de manejo do solo, para avaliar a decomposição da palhada. Para avaliar os atributos biológicos, um experimento com

  17. Biological Removal of Propylene Glycol from Wastewater and its Degradation in Soil by the Activated Sludge Consortia

    Directory of Open Access Journals (Sweden)

    G.R Moussavi

    2009-07-01

    Full Text Available "n "nBackground and Objectives : Propylene glycol is the main compound of anti-freezing chemicals. A significant amount of propylene glycol is released to the environment after application and contaminates the soil. The main objective of this study was to determine the biological removal of propylene glycol from wastewater and its degradation in soil by the isolated bacteria from activated sludge process."nMaterials and Methods: In the present study, the sludge taken from the return flow in a local activated sludge treatment system was used as the initial seed. The performance of the bioreactor in treating the wastewater was evaluated at four different retention times of 18, 12, 6 and 4 h all with the inlet COD concentration of 1000 mg/L. This phase lasted around 4 months. Then, a part of the adapted microorganisms were transported from the bioreactor to the soil which was synthetically contaminated to the propylene glycol."nResults: The average of propylene glycol removal efficiency from the wastewater in detention times of 18, 12, 8 and 4 h in steady state conditions was 98.6%, 97.1%, 86.4% and 62.2% respectively. Also, the maximum degradation in soil was found to be 97.8%."nConclusion: According to the results obtained from this study, it appears that propylene glycol is inherently well biodegradable and can be biodegraded in liquid phase and soil after a short period of adaptation.

  18. "Candidatus Propionivibrio aalborgensis": A Novel Glycogen Accumulating Organism Abundant in Full-Scale Enhanced Biological Phosphorus Removal Plants.

    Science.gov (United States)

    Albertsen, Mads; McIlroy, Simon J; Stokholm-Bjerregaard, Mikkel; Karst, Søren M; Nielsen, Per H

    2016-01-01

    Enhanced biological phosphorus removal (EBPR) is widely used to remove phosphorus from wastewater. The process relies on polyphosphate accumulating organisms (PAOs) that are able to take up phosphorus in excess of what is needed for growth, whereby phosphorus can be removed from the wastewater by wasting the biomass. However, glycogen accumulating organisms (GAOs) may reduce the EBPR efficiency as they compete for substrates with PAOs, but do not store excessive amounts of polyphosphate. PAOs and GAOs are thought to be phylogenetically unrelated, with the model PAO being the betaproteobacterial "Candidatus Accumulibacter phosphatis" (Accumulibacter) and the model GAO being the gammaproteobacterial "Candidatus Competibacter phosphatis". Here, we report the discovery of a GAO from the genus Propionivibrio, which is closely related to Accumulibacter. Propionivibrio sp. are targeted by the canonical fluorescence in situ hybridization probes used to target Accumulibacter (PAOmix), but do not store excessive amounts of polyphosphate in situ. A laboratory scale reactor, operated to enrich for PAOs, surprisingly contained co-dominant populations of Propionivibrio and Accumulibacter. Metagenomic sequencing of multiple time-points enabled recovery of near complete population genomes from both genera. Annotation of the Propionivibrio genome confirmed their potential for the GAO phenotype and a basic metabolic model is proposed for their metabolism in the EBPR environment. Using newly designed fluorescence in situ hybridization (FISH) probes, analyses of full-scale EBPR plants revealed that Propionivibrio is a common member of the community, constituting up to 3% of the biovolume. To avoid overestimation of Accumulibacter abundance in situ, we recommend the use of the FISH probe PAO651 instead of the commonly applied PAOmix probe set. PMID:27458436

  19. “Candidatus Propionivibrio aalborgensis”: A Novel Glycogen Accumulating Organism Abundant in Full-Scale Enhanced Biological Phosphorus Removal Plants

    Science.gov (United States)

    Albertsen, Mads; McIlroy, Simon J.; Stokholm-Bjerregaard, Mikkel; Karst, Søren M.; Nielsen, Per H.

    2016-01-01

    Enhanced biological phosphorus removal (EBPR) is widely used to remove phosphorus from wastewater. The process relies on polyphosphate accumulating organisms (PAOs) that are able to take up phosphorus in excess of what is needed for growth, whereby phosphorus can be removed from the wastewater by wasting the biomass. However, glycogen accumulating organisms (GAOs) may reduce the EBPR efficiency as they compete for substrates with PAOs, but do not store excessive amounts of polyphosphate. PAOs and GAOs are thought to be phylogenetically unrelated, with the model PAO being the betaproteobacterial “Candidatus Accumulibacter phosphatis” (Accumulibacter) and the model GAO being the gammaproteobacterial “Candidatus Competibacter phosphatis”. Here, we report the discovery of a GAO from the genus Propionivibrio, which is closely related to Accumulibacter. Propionivibrio sp. are targeted by the canonical fluorescence in situ hybridization probes used to target Accumulibacter (PAOmix), but do not store excessive amounts of polyphosphate in situ. A laboratory scale reactor, operated to enrich for PAOs, surprisingly contained co-dominant populations of Propionivibrio and Accumulibacter. Metagenomic sequencing of multiple time-points enabled recovery of near complete population genomes from both genera. Annotation of the Propionivibrio genome confirmed their potential for the GAO phenotype and a basic metabolic model is proposed for their metabolism in the EBPR environment. Using newly designed fluorescence in situ hybridization (FISH) probes, analyses of full-scale EBPR plants revealed that Propionivibrio is a common member of the community, constituting up to 3% of the biovolume. To avoid overestimation of Accumulibacter abundance in situ, we recommend the use of the FISH probe PAO651 instead of the commonly applied PAOmix probe set. PMID:27458436

  20. Functionally relevant microorganisms to enhanced biological phosphorus removal performance at full-scale wastewater treatment plants in the United States.

    Science.gov (United States)

    Gu, April Z; Saunders, A; Neethling, J B; Stensel, H D; Blackall, L L

    2008-08-01

    The abundance and relevance ofAccumulibacter phosphatis (presumed to be polyphosphate-accumulating organisms [PAOs]), Competibacter phosphatis (presumed to be glycogen-accumulating organisms [GAOs]), and tetrad-forming organisms (TFOs) to phosphorus removal performance at six full-scale enhanced biological phosphorus removal (EBPR) wastewater treatment plants were investigated. Coexistence of various levels of candidate PAOs and GAOs were found at these facilities. Accumulibacter were found to be 5 to 20% of the total bacterial population, and Competibacter were 0 to 20% of the total bacteria population. The TFO abundance varied from nondetectable to dominant. Anaerobic phosphorus (P) release to acetate uptake ratios (P(rel)/HAc(up)) obtained from bench tests were correlated positively with the abundance ratio of Accumulibacter/(Competibacter +TFOs) and negatively with the abundance of (Competibacter +TFOs) for all plants except one, suggesting the relevance of these candidate organisms to EBPR processes. However, effluent phosphorus concentration, amount of phosphorus removed, and process stability in an EBPR system were not directly related to high PAO abundance or mutually exclusive with a high GAO fraction. The plant that had the lowest average effluent phosphorus and highest stability rating had the lowest P(rel)/HAc(up) and the most TFOs. Evaluation of full-scale EBPR performance data indicated that low effluent phosphorus concentration and high process stability are positively correlated with the influent readily biodegradable chemical oxygen demand-to-phosphorus ratio. A system-level carbon-distribution-based conceptual model is proposed for capturing the dynamic competition between PAOs and GAOs and their effect on an EBPR process, and the results from this study seem to support the model hypothesis. PMID:18751532