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Jie Hou, Ling Xia, Tao Ma, Yiqing Zhang, Yiyong Zhou, Xugang He
This study aim to enhance nitrogen removal performance via shifting nitrogen removal pathway from nitrate to nitrite pathway. It was demonstrated that nitrite pathway was successfully and stably achieved in CWs by using modified intermittent aeration control with aeration 20min/non-aeration 100min and reducing DO concentration during aeration, nitrite in the effluent could accumulate to over 70% of the total oxidized nitrogen. Q-PCR analysis showed that nitrifying microbial communities were optimized under the alternating anoxic and aerobic conditions, ammonia oxidizing bacteria increased from 7...
February 10, 2017: Bioresource Technology
Didem Güven, Oytun Hanhan, Elif Ceren Aksoy, Güçlü Insel, Emine Çokgör
A lab-scale Sequencing Batch Reactor (SBR) was implemented to investigate biological treatability and kinetic characteristics of paint shop wastewater (PSW) together with main stream wastewater (MSW) of a bus production factory. Readily biodegradable and slowly biodegradable COD fractions of MWS were determined by respirometric analysis: 4.2% (SS), 10.4% (SH) and 59.3% (XS). Carbon and nitrogen removal performance of the SBR feeding with MSW alone were obtained as 89% and 58%, respectively. When PSW was introduced to MSW, both carbon and nitrogen removal were deteriorated...
January 29, 2017: Journal of Hazardous Materials
Yao Du, Teng Ma, Yamin Deng, Shuai Shen, Zongjie Lu
High levels of ammonium from anthropogenic sources threaten the quality of surface waters and groundwaters in some areas worldwide, but elevated ammonium levels of natural sources also have been identified. High levels of ammonium have been detected in both surface water and shallow groundwater of the Jianghan Plain, an alluvial plain of the Yangtze River. This study used N isotopes coupled with ancillary chemistry to identify ammonium in this region. Ammonium in the Tongshun River (up to 10.25 mg L(-1)) showed a sharp accumulation in the upstream and gradual attenuation in the downstream...
February 16, 2017: Environmental Science. Processes & Impacts
K Solon, X Flores-Alsina, C Kazadi Mbamba, D Ikumi, E I P Volcke, C Vaneeckhaute, G Ekama, P A Vanrolleghem, D J Batstone, K V Gernaey, U Jeppsson
The objective of this paper is to report the effects that control/operational strategies may have on plant-wide phosphorus (P) transformations in wastewater treatment plants (WWTP). The development of a new set of biological (activated sludge, anaerobic digestion), physico-chemical (aqueous phase, precipitation, mass transfer) process models and model interfaces (between water and sludge line) were required to describe the required tri-phasic (gas, liquid, solid) compound transformations and the close interlinks between the P and the sulfur (S) and iron (Fe) cycles...
February 6, 2017: Water Research
Laura A Sauder, Mads Albertsen, Katja Engel, Jasmin Schwarz, Per H Nielsen, Michael Wagner, Josh D Neufeld
Thaumarchaeota have been detected in several industrial and municipal wastewater treatment plants (WWTPs), despite the fact that ammonia-oxidizing archaea (AOA) are thought to be adapted to low ammonia environments. However, the activity, physiology and metabolism of WWTP-associated AOA remain poorly understood. We report the cultivation and complete genome sequence of Candidatus Nitrosocosmicus exaquare, a novel AOA representative from a municipal WWTP in Guelph, Ontario (Canada). In enrichment culture, Ca...
February 14, 2017: ISME Journal
Yuanyuan Miao, Liang Zhang, Baikun Li, Qian Zhang, Simeng Wang, Yongzhen Peng
Intermittent aeration and bio-augmentation were integrated to enhance single-stage partial nitrification-anammox (SPN/A) stability over 235-day operational period treating low-strength sewage. The effect of bio-augmentation sludge (with different abundances of ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB)) was determined. Partial nitrification sludge based bio-augmentation increased the total nitrogen (TN) removal efficiency from 29.1% to 70%, followed by the nitrification sludge (from 38...
January 27, 2017: Bioresource Technology
Fabrizio Sabba, Cristian Picioreanu, Joshua P Boltz, Robert Nerenberg
Wastewater treatment plants can be significant sources of nitrous oxide (N2O), a potent greenhouse gas. While our understanding of N2O emissions from suspended-growth processes has advanced significantly, less is known about emissions from biofilm processes. Biofilms may behave differently due to their substrate gradients and microbial stratification. In this study, we used mathematical modeling to explore the mechanisms of N2O emissions from nitrifying and denitrifying biofilms. Our ammonia-oxidizing bacteria biofilm model suggests that N2O emissions from biofilm can be significantly greater than from suspended-growth systems...
February 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Alvaro J Romera, Rogerio Cichota, Pierre C Beukes, Pablo Gregorini, Val O Snow, Iris Vogeler
Intensification of pastoral dairy systems often means more nitrogen (N) leaching. A number of mitigation strategies have been proposed to reduce or reverse this trend. The main strategies focus on reducing the urinary N load onto pastures or reducing the rate of nitrification once the urine has been deposited. Restricted grazing is an example of the former and the use of nitrification inhibitors an example of the latter. A relevant concern is the cost effectiveness of these strategies, independently and jointly...
January 2017: Journal of Environmental Quality
Tao Huang, Xiaotang Ju, Hao Yang
Nitrate leaching is one of the most important pathways of nitrogen (N) loss which leads to groundwater contamination or surface water eutrophication. Clarifying the rates, controlling factors and characteristics of nitrate leaching is the pre-requisite for proposing effective mitigation strategies. We investigated the effects of interactions among chemical N fertilizer, straw and manure applications on nitrogen leaching in an intensively managed calcareous Fluvo-aquic soil with winter wheat-summer maize cropping rotations on the North China Plain from October 2010 to September 2013 using ceramic suction cups and seepage water calculations based on a long-term field experiment...
February 8, 2017: Scientific Reports
Bradley Young, Robert Delatolla, Turki Abujamel, Kevin Kennedy, Edith Laflamme, Alain Stintzi
The moving bed biofilm reactor (MBBR), operated as a post carbon removal system, requires long start-up times in comparison to carbon removal systems due to slow growing autotrophic organisms. This study investigates the use of carriers seeded in a carbon rich treatment system prior to inoculation in a nitrifying MBBR system to promote the rapid development of nitrifying biofilm in an MBBR system at temperatures between 6 and 8 °C. Results show that nitrification was initiated by the carbon removal carriers after 22 h of operation...
February 6, 2017: Bioprocess and Biosystems Engineering
Qingkai Ren, Yang Yu, Suiyi Zhu, Dejun Bian, Mingxin Huo, Dandan Zhou, Hongliang Huo
 A novel micro-pressure swirl reactor (MPSR) was designed and applied to treat domestic wastewater at low temperature by acclimating microbial biomass with steadily decreasing temperature from 15 to 3 °C. Chemical oxygen demand (COD) was constantly removed by 85% and maintained below 50 mg L(-1) in the effluent during the process. When the air flow was controlled at 0.2 m(3) h(-1), a swirl circulation was formed in the reactor, which created a dissolved oxygen (DO) gradient with a low DO zone in the center and a high DO zone in the periphery for denitrification and nitrification...
February 6, 2017: Biodegradation
Yating Li, Yanru Wang, Lin Fu, Yizhan Gao, Haixia Zhao, Weizhi Zhou
An aerobic marine bacterium Vibrio sp. Y1-5 was screened to achieve efficient nitrate and ammonium removal simultaneously and fix nitrogen in cells without N loss. Approximately 98.0% of nitrate (100mg/L) was removed in 48h through assimilatory nitrate reduction and nitrate reductase was detected in the cytoplasm. Instead of nitrification, the strain assimilated ammonium directly, and it could tolerate as high as 1600mg/L ammonium concentration while removing 844.6mg/L. In addition, ammonium assimilation occurred preferentially in the medium containing nitrate and ammonium with a total nitrogen (TN) removal efficiency of 80...
January 27, 2017: Bioresource Technology
Wen Xu, Yan-Peng Cai, Zhi-Feng Yang, Xin-An Yin, Qian Tan
Leached cinnamon soil is the main agricultural soil distributed in the North China Plain. In this research, leached cinnamon soil samples were collected in the upper basin of Miyun Reservoir (northeast of Beijing, China). The BaPS method (Barometric Process Separation) was applied to measure nitrification, denitrification and respiration rates. The rates of nitrification, denitrification and respiration were 0-120.35 μg N/kg SDW h, 0-246.86 μg N/kg SDW h and 0.17-225.85 μg C/kg SDW h (Soil Dry Weight, SDW), respectively...
February 6, 2017: Scientific Reports
Akihiko Terada, Sho Sugawara, Keisuke Hojo, Yuki Takeuchi, Shohei Riya, Willie F Harper, Tomoko Yamamoto, Megumi Kuroiwa, Kazuo Isobe, Chie Katsuyama, Yuichi Suwa, Keisuke Koba, Masaaki Hosomi
The goal of this study was to elucidate the mechanisms of N2O production from a bioreactor for partial nitrification (PN). Ammonia-oxidizing bacteria (AOB) enriched from a sequencing batch reactor (SBR) were subjected to N2O production pathway tests. The N2O pathway test was initiated by supplying an inorganic medium to ensure an initial NH4(+)-N concentration of 160 mg-N/L, followed by (15)NO2(-) (20 mg-N/L) and dual (15)NH2OH (each 17 mg-N/L) spikings to quantify isotopologs of gaseous N2O ((44)N2O, (45)N2O, and (46)N2O)...
February 6, 2017: Environmental Science & Technology
Heng Dong, Dong Wei, Siyu Wang, Xiaodong Wang, Tao Yan, Liangguo Yan, Bin Du, Qin Wei
The purpose of this study was to evaluate the effect of toxic 4-chlorophenol (4-CP) on the production of soluble microbial products (SMP) in aerobic granular sludge system. Compared with control experiment, NH4(+)-N removal efficiency generally reduced by 37.90% after the exposure of 4-CP of 10 mg L(-1), indicating that 4-CP had a toxic effect on the performance of biological nitrification. Meanwhile, the contents of polysaccharides (PS) and proteins (PN) of SMP increased from 31.0±0.32 and 0.8±0.12 mg L(-1) to 39...
February 6, 2017: Environmental Technology
Yangwu Chen, Shuhuan Lan, Longhui Wang, Shiyang Dong, Houzhen Zhou, Zhouliang Tan, Xudong Li
The performance and stabilization of biological wastewater treatment systems (1)are closely related to the microbial community structure and dynamics. In this paper, the effects and mechanisms of influent composition, process configuration, operating parameters (dissolved oxygen [DO], pH, hydraulic retention time [HRT] and sludge retention time [SRT]) and environmental condition (temperature) to the change of microbial community structure and process performance (nitrification, denitrification, biological phosphorus removal, organics mineralization and utilization, etc...
January 27, 2017: Chemosphere
Catiane Pelissari, Miriam Guivernau, Marc Viñas, Samara Silva de Souza, Joan García, Pablo Heleno Sezerino, Cristina Ávila
The dynamics of the active microbial populations involved in nitrogen transformation in a vertical subsurface flow constructed wetland (VF) treating urban wastewater was assessed. The wetland (1.5m(2)) operated under average loads of 130gCODm(-2)d(-1) and 17gTNm(-2)d(-1) in Period I, and 80gCODm(-2)d(-1) and 19gTNm(-2)d(-1) in Period II. The hydraulic loading rate (HLR) was 375mmd(-1) and C/N ratio was 2 in both periods. Samples for microbial characterization were collected from the filter medium (top and bottom layers) of the wetland, water influent and effluent at the end of Periods I (Jun-Oct) and II (Nov-Jan)...
February 1, 2017: Science of the Total Environment
Junhao Qin, Chuxia Lin, Patrick Cheruiyot, Sandra Mkpanam, Nelisiwe Good-Mary Duma
Microcosm experiments were conducted to examine the effects of rainwater-borne H2O2 on inactivation of water-borne coliforms, oxidation of ammonia and nitrite, and degradation of organic pollutants in canal and urban lake water. The results show that the soluble iron in the investigated water samples was sufficiently effective for reaction with H2O2 in the simulated rainwater-affected stagnant water to produce OH (Fenton reaction), which inactivated coliform bacteria even at a H2O2 dose as low as 5 μM within just 1 min of contact time...
January 25, 2017: Chemosphere
Dong Wei, Keyi Zhang, Huu Hao Ngo, Wenshan Guo, Siyu Wang, Jibin Li, Fei Han, Bin Du, Qin Wei
In present study, the feasibility of partial nitrification (PN) process achievement and its greenhouse gas emission were evaluated in a sequencing batch biofilm reactor (SBBR). After 90days' operation, the average effluent NH4(+)-N removal efficiency and nitrite accumulation rate of PN-SBBR were high of 98.2% and 87.6%, respectively. Both polysaccharide and protein contents were reduced in loosely bound extracellular polymeric substances (LB-EPS) and tightly bound EPS (TB-EPS) during the achievement of PN-biofilm...
January 25, 2017: Bioresource Technology
Doaa Bassuney, Ahmed Tawfik
The aim of the study is to assess the efficiency of a novel bioremediation system namely baffled duck weed pond (BDWP) system for treatment of agricultural drainage water containing pharmaceuticals at different hydraulic retention times (HRTs). The removal efficiencies of acetaminophen (ACT), amoxicillin (AMX) and ampicillin (AMP) increased from 69.3±8.6 to 87.3 ±3.5%, from 52.9±9.4 to 82.9±5.2% and from 55.3±7.9 to 90.6±2.8% at increasing the HRT from 6 to 8 d., respectively. However, ACT, AMX and AMP removal efficiencies were slightly improved at increasing the HRT from 8 to 12 d...
February 3, 2017: International Journal of Phytoremediation
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