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Search Results: 1 - 10 of 10071 matches for " biological phosphorus removal "
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Influence of Azo Dye on Metabolism of Phosphorus Accumulating Organisms Linked to Transformation of Intracellular Storage Products  [PDF]
Fang Fang, Hui Chen, Jing-Yang Luo, Zhe-Ying Zhu, Jia-Shun Cao
Journal of Geoscience and Environment Protection (GEP) , 2018, DOI: 10.4236/gep.2018.65001
Abstract: In this study, the influence of azo dye of methyl red (MR) on COD, dye and phosphorus removal and the transformation of polyhydroxyalkanoate (PHA) and glycogen of phosphate accumulating organisms in enhanced biological phosphorus removal (EBPR) system were investigated. The results indicated COD and dye removal efficiencies were decreased from 97.9% to 72.8% and 99.7% to 82.0%, respectively, when MR concentration was increased from 0 to 40 mg/L. Low MR concentration (5 mg/L) had no influence on P removal and transformation of PHA and glycogen. However, P removal, PHA production and consumption, and glycogen replenishment were seriously inhibited at high MR concentration, while glycogen hydrolysis was simulated at MR concentration of 20 and 40 mg/L. The transformations of PHA and glycogen at aerobic condition were more sensitive to those at anaerobic condition at high MR concentration. These results demonstrated dye and its intermediate products would inhibit the metabolism of polyphosphate accumulating organisms, which should be taken into account in future work.
Saldarriaga,Julio César; Hoyos,Dora ángela; Correa,Mauricio Andrés;
Revista EIA , 2011,
Abstract: two different systems of biological treatment were operated (anaerobic-anoxic-aerobic -a2o-, namely, arrangement i, and aerobic-anoxic, namely, arrangement ii). after modification by the addition of anoxkaldnes as a support medium for the aerobic chambers, they were used in the simultaneously elimination of organic material and two nutrients:nitrogen and phosphorus. the arrangements involved the growing of suspending biomass in anaerobic and anoxic chambers, and combined (suspended and attached) in the aerobic chambers. during the experiments, recirculation rates (aerobic-anoxic) within 100 and 300% were guaranteed, applied in the same experimental periods, from the secondary settler toward the anaerobic chamber in the arrangement i and toward the anoxic chamber in arrangement ii, with rates of 100%. the hydraulic retention time (hrt) varied within 10 and 24 hours per arrangement, and the solids retention time (srt) remained between 15 and 20 days. the processes were evaluated using synthetic residual water with composition similar to the found in the domestic residual water; it was prepared from milk powder whey with the addition of macro and micro-nutrients. the percentage of removal material during the experiments reached values larger than 90% in cod and close to 85% in n and p; these values correspond to the median of the experimental data, meaning that they include all the data obtained from the different recirculation rates (aerobic-anoxic) and for a total experimental period of 14 months.
Tratamento de esgoto sanitário em reator híbrido em bateladas sequenciais: eficiência e estabilidade na remo??o de matéria organica e nutrientes (N, P)
Lamego Neto, Luiz Gonzaga;Costa, Rejane Helena Ribeiro da;
Engenharia Sanitaria e Ambiental , 2011, DOI: 10.1590/S1413-41522011000400013
Abstract: 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.
Remo??o biológica de fósforo em reatores em bateladas sequenciais com diferentes tempos de reten??o de sólidos
Henrique, Israel Nunes;Sousa, José Tavares de;Ceballos, Beatriz Susana Ovruski de;Brasil, Danielle Patrício;
Engenharia Sanitaria e Ambiental , 2010, DOI: 10.1590/S1413-41522010000200012
Abstract: in recent years, there has been an increasing need to design wastewater treatment systems that are capable of removing both organic material and nutrients, notably nitrogen and phosphorus. this study evaluated biological phosphorus removal by activated sludge systems fed with domestic sewage and operating as sequencing batch reactors (sbr) with different solids retention times (srt) namely 20, 5 and 3 days. this was supported by respirometry experiments at bench scale using acetate as the source of organic carbon. the results showed satisfactory total phosphorus removal efficiencies mean values between 79-82% for the three regimes with the best removal efficiency occurring in the sbr operating with a five-day srt.
Experimental study on phosphorus removal of silk factory cocoon wastewater

Zhou Jian,He Wenshi,Zhang Qin,Zhang Zhi,

环境工程学报 , 2007,
Abstract: 针对丝绸厂汰头废水高有机物浓度高氮磷的特点,对该废水的化学除磷工艺及生物化学组合除磷工艺的除磷效能进行了对比研究,考察了有机负荷、运行工况、工艺组合、药剂种类和投加量等对除磷效能的影响.试验结果表明:对汰头废水采用厌氧-生物除磷-生物脱氮-化学除磷组合工艺除磷经济高效,当生物除磷SBBR工艺单元有机负荷为3 kgBOD5/m3·d,运行工况为进水0.5 h-厌氧2 h-曝气4 h-沉淀1 h-排水0.5 h,化学除磷工艺单元投加60 mg/L聚合氯化铝(PAC)时,可使COD及PO3-4分别为10 000 mg/L和114 mg/L的进水,出水COD及PO3-4分别为93 mg/L和0.23 mg/L;总ηCOD91.5%,ηPO3-4为99.8%.其中生物除磷工艺单元承担的ηPO3-4为75%;化学除磷工艺单元承担的ηPO3-4为24.8%.
Nitrogen and phosphorus removal in pilot-scale anaerobic-anoxic oxidation ditch system

PENG Yongzhen,HOU Hongxun,WANG Shuying,CUI Youwei,Zhiguo Yuan,

环境科学学报(英文版) , 2008,
Abstract: To achieve high efficiency of nitrogen and phosphorus removal and to investigate the rule of simultaneous nitrification and denitrification phosphorus removal(SNDPR),a whole course of SNDPR damage and recovery was studied in a pilot-scale,anaerobicanoxic oxidation ditch(OD),where the volumes of anaerobic zone,anoxic zone,and ditches zone of the OD system were 7,21,and 280L,respectively.The reactor was fed with municipal wastewater with a flow rate of 336 L/d.The concept of simultaneous nitrification and denitrification (SND)rate(rSND) was put forward to quantify SND.The results indicate that:(1)high nitrogen and phosphorus removal efficiencies were achieved during the stable SND phase,total nitrogen (TN) and total phosphate(TP) removal rates were 80%and 85%,respectively;(2)when the system was aerated excessively,the stability of SND was damaged,and rSND dropped from 80% to 20%or less;(3)the natural logarithm of the ratio of NOx to MJ4 in the effluent had a linear correlation to oxidation-reduction potential (ORP);(4)when NO3- was less than 6 mg/L.high phosphorus removal efficiency could be achieved;(5)denitrifying phosphorus removal (DNPR) could take place in the anaerobic-anoxic OD system.The major innovation was that the SND rate was devised and quantified.
Nitrous oxide emission by denitrifying phosphorus removal culture using polyhydroxyalkanoates as carbon source
Yan Zhou,Melvin Lim,Soekendro Harjono,Wun Jern Ng,
Yan Zhou
,Melvin Lim,Soekendro Harjono,Wun Jern Ng

环境科学学报(英文版) , 2012,
Abstract: Nitrous oxide (N2O) emission has been reported to be enhanced during denitrification when internally-stored compounds are used as carbon sources. However, negligible N2O emissions have been detected in the few studies where polyhydroxyalkanoates (PHA) were specifically used. This study investigated and compared the potential enhancement of N2O production, based on utilization of an internally-stored polymer and external carbon (acetate) by a denitrifying phosphorus removal culture. Results indicated that at relatively low chemical oxygen demand-to-nitrogen (COD/N) ratios, more nitrite was reduced to N2O in the presence of an external carbon source as compared to an internal carbon source (PHA). At relatively higher COD/N ratios, similar N2O reduction rates were obtained in all cases regardless of the type of carbon source available. N2O reduction rates were, however, generally higher in the presence of an internal carbon source. Results from the study imply that when the presence of an external carbon source is not sufficient to support denitrification, it is likely competitively utilized by different metabolic pathways of denitrifying polyphosphate accumulating organisms (DPAOs) and other ordinary denitrifiers. This study also reveals that the consumption of PHA is potentially the rate-limiting step for N2O reduction during denitrification.
Research Advance in polyphosphate-accumulating microorganisms in enhanced biological phosphorus removal process

ZHENG Jinwei,RAN Wei,ZHONG Zengtao,HE Jian,

应用生态学报 , 2004,
Abstract: This paper discussed the function of enhanced biological phosphorus removal (EBPR) in P pollution control,P containing wastewater treatment and P resources recovery,and summarized the metabolic characteristics,research progress and methodologies of polyphosphate-accumulating organisms (PAOs).Although polyphosphate has been found in many organisms,only few of PAOs were isolated,cultured and identified.Culture medium formulation is the key to isolate PAOs and to study the microbial accumulation of polyphosphate,and the competition of glycogen-accumulating organisms (GAOs) with PAOs for carbon resources is one of the reasons of low EBPR efficiency.Modern scientific methods such as fluorescent in situ hybridization,confocal laser scanning microscope,microautoradiography,and in vivo NMR spectroscopy,provided powerful tools to analyze PAO species composition,spatial structure and functional properties under field conditions.The knowledge of PAO is valuable to enhance the P removal efficiency in water treatment plant,and to improve our understanding on P transformation and transferring in environment.
Denitrifying phosphorus removal in a step-feed CAST with alternating anoxic-oxic operational strategy

MA Juan,PENG Yong-zhen,WANG Shu-ying,WANG Li,LIU Yang,MA Ning-ping,

环境科学学报(英文版) , 2009,
Abstract: A bench-scale cyclic activated sludge technology (CAST) was operated to study the biological phosphorus removal performance and a series of batch tests was carried out to demonstrate the accumulation of denitrifying polyphosphate-accumulating organisms (DNPAOs) in CAST system. Under all operating conditions, step-feed CAST with enough carbon sources in influent had the highest nitrogen and phosphorus removal e ciency as well as good sludge settling performance. The average removal rate of COD, NH4 +-N, PO4 3??-P and total nitrogen (TN) was 88.2%, 98.7%, 97.5% and 92.1%, respectively. The average sludge volume index (SVI) was 133 mL/g. The optimum anaerobic/aerobic/anoxic (AOA) conditions for the cultivation of DNPAOs could be achieved by alternating anoxic/oxic operational strategy, thus a significant denitrifying phosphorus removal occurred in step-feed CAST. The denitrification of NOx??-N completed quickly due to step-feed operation and enough carbon sources, which could enhance phosphorus release and further phosphorus uptake capability of the system. Batch tests also proved that polyphosphate-accumulating organisms (PAOs) in the step-feed process had strong denitrifying phosphorus removal capacity. Both nitrate and nitrite could be used as electron acceptors in denitrifying phosphorus removal. Low COD supply with step-feed operation strategy would favor DNPAOs accumulation.
Effect of the COD and Total Phosphorus Concentration on Biological Phosphorus Removal Supplied with Acetate as a Sole Carbon Source

Ruan Wenquan,Zou Hua,Chen Jian,

环境科学 , 2002,
Abstract: The effect of the concentration of acetate and total phosphorus on biological phosphorus removal process in sequencing batch reactor fed with sodium acetate (as sole carbon source) was studied in this paper. The reason of the inefficiency of phosphorus removal by sludge fed with high concentration acetate solution was analyzed. The results indicated that when COD<600 mg·L-1 the phosphorus removal increased with the increase of COD/TP; and this removal increased obviously when COD/TP<50 but not when COD/TP>50. The phosphorus removal descended at high acetate concentration ( COD>600 mg·L-1) and broke down when COD>1000 mg·L-1 . It is the transmissions of high acetate concentration from the anaerobic stage to the aerobic stage that led to the proliferation of the filamentous microorganism and the expansion of sludge, then polyP bacteria was wash out, which resulted in the drop of phosphorus removal.
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