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Weiqiang Zhu, Peiyu Zhang, Deshuang Yu, Huiyu Dong, Jin Li
A sequencing batch reactor (SBR) was used to test the nitrogen removal performance of anaerobic ammonium oxidation (ANAMMOX) in presence of organic matter. Mesophilic operation (30 ± 0.5 °C) was performed with influent pH 7.5. The results showed, independent of organic matter species, ANAMMOX reaction was promoted when COD was lower than 80 mg/L. However, specific ANAMMOX activity decreased with increasing organic matter content. Ammonium removal efficiency decreased to 80% when COD of sodium succinate, sodium potassium tartrate, peptone and lactose were 192...
February 9, 2017: Biodegradation
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
Zhi-Guo Wu, Fang Wang, Li-Qun Ning, Robert D Stedtfeld, Zong-Zheng Yang, Jing-Guo Cao, Hong-Jie Sheng, Xin Jiang
Several bacteria have been isolated to degrade 4-chloronitrobenzene. Degradation of 4-chloronitrobenzene by Cupriavidus sp. D4 produces 5-chloro-2-picolinic acid as a dead-end by-product, a potential pollutant. To date, no bacterium that degrades 5-chloro-2-picolinic acid has been reported. Strain f1, isolated from a soil polluted by 4-chloronitrobenzene, was able to co-metabolize 5-chloro-2-picolinic acid in the presence of ethanol or other appropriate carbon sources. The strain was identified as Achromobacter sp...
February 2, 2017: Biodegradation
Lamia Ayed, Nedra Asses, Nadia Chammem, Nada Ben Othman, Moktar Hamdi
Table olive processing wastewaters constitute a dangerous environmental problem in the Mediterranean countries because of their large volumes, high organic matter and salt concentration. The quantity and the characteristics of wastewaters produced, and thus, their environmental impact, varied depending on the season, varieties, soil and process employed. Several chemicals, biological and combined technologies have proven effective at bringing down organic pollution and toxicity of these effluents. Advanced oxidation processes have recognized as highly efficient treatments for the degradation of organic matter...
January 23, 2017: Biodegradation
Hunter W Schroer, Kathryn L Langenfeld, Xueshu Li, Hans-Joachim Lehmler, Craig L Just
Insensitive munitions explosives are new formulations that are less prone to unintended detonation compared to traditional explosives. While these formulations have safety benefits, the individual constituents, such as 2,4-dinitroanisole (DNAN), have an unknown ecosystem fate with potentially toxic impacts to flora and fauna exposed to DNAN and/or its metabolites. Fungi may be useful in remediation and have been shown to degrade traditional nitroaromatic explosives, such as 2,4,6-trinitrotoluene and 2,4-dinitrotoluene, that are structurally similar to DNAN...
December 2, 2016: Biodegradation
Guang-Feng Yang, Li-Juan Feng, Cai-Rong Guo, Tian Xia, Xiang-Yang Xu, Liang Zhu
The initial formation of biofilm and the removal performance of pollutants in biological pretreatment process for polluted raw water were limited due to the oligotrophic niche in raw water. In this study, the feasibility of using pre-inoculation biofilm formed under nutrients enhanced condition for polluted raw water treatment was analyzed in nine batch reactors. Results showed that the pollutants removal performance of biofilm was improved under nutrients enhanced conditions. Ammonia oxidation rate (AOR) was exponentially increased with the increasing in NH4(+)-N levels, and organic matter removal rate (ORR) was positively related to the initial total organic carbon (TOC) concentration...
December 2, 2016: Biodegradation
Alberto Ordaz, Mariana Sánchez, Rodrigo Rivera, Rafael Rojas, Alejandro Zepeda
A nitrifying consortium was kinetically, stoichiometrically and molecularly characterized via the in situ pulse respirometric method and pyrosequencing analysis before and after the addition of m-cresol (25 mg C L(-1)) in a sequencing batch reactor (SBR). Five important kinetic and stoichiometric parameters were determined: the maximum oxygen uptake rate, the maximum nitrification rate, the oxidation yield, the biomass growth yield, and the substrate affinity constant. An inhibitory effect was observed in the nitrification process with a recovery of this by up to eight SBR cycles after m-cresol was added to the system...
November 30, 2016: Biodegradation
Kozet Yapsakli, Cigdem Kalkan Aktan, Bulent Mertoglu
For a successful nitrogen removal, Anammox process needs to be established in line with a stable partial nitritation pretreatment unit since wastewater influent is mostly unsuitable for direct treatment by Anammox. Partial nitritation is, however, a critical bottleneck for the nitrogen removal since it is often difficult to maintain the right proportions of NO2-N and NH4-N during long periods of time for Anammox process. This study investigated the potential of Anammox-zeolite biofilter to buffer inequalities in nitrite and ammonium nitrogen in the influent feed...
November 2, 2016: Biodegradation
Jiang Tian, Chenlei Yu, Yingwen Xue, Ruixue Zhao, Jing Wang, Lanzhou Chen
The novel trichlorfon (TCF)-degrading bacterium PA F-3, identified as Bacillus tequilensis, was isolated from pesticide-polluted soils by using an effective screening and domesticating procedure. The TCF biodegradation pathways of PA F-3 were also systematically elucidated. As revealed by high-performance liquid chromatography, the TCF residues in the mineral salt medium demonstrated that PA F-3 can utilize TCF as its sole carbon source and reach the highest degradation of 71.1 % at an initial TCF concentration of 200 mg/L within 5 days...
November 2016: Biodegradation
Daisuke Inoue, Tsubasa Tsunoda, Kazuko Sawada, Norifumi Yamamoto, Yuji Saito, Kazunari Sei, Michihiko Ike
In recent years, several strains capable of degrading 1,4-dioxane have been isolated from the genera Pseudonocardia and Rhodococcus. This study was conducted to evaluate the 1,4-dioxane degradation potential of phylogenetically diverse strains in these genera. The abilities to degrade 1,4-dioxane as a sole carbon and energy source and co-metabolically with tetrahydrofuran (THF) were evaluated for 13 Pseudonocardia and 12 Rhodococcus species. Pseudonocardia dioxanivorans JCM 13855(T), which is a 1,4-dioxane degrading bacterium also known as P...
November 2016: Biodegradation
Jinkai Xue, Yanyan Zhang, Yang Liu, Mohamed Gamal El-Din
Batch experiments were performed to evaluate biodegradation of raw and ozonated oil sands process-affected water (OSPW) under denitrifying anoxic and nitrifying aerobic conditions for 33 days. The results showed both the anoxic and aerobic conditions are effective in degrading OSPW classical and oxidized naphthenic acids (NAs) with the aerobic conditions demonstrating higher removal efficiency. The reactors under nitrifying aerobic condition reduced the total classical NAs of raw OSPW by 69.1 %, with better efficiency for species of higher hydrophobicity...
November 2016: Biodegradation
Gulsum Yilmaz, Umit Bozkurt, Karin Aleksanyan Magden
Aerobic granulation is a promising technology for wastewater treatment, but problems regarding its formation and stability need to be solved. Divalent metal ions, especially Ca(2+), Mg(2+) and Mn(2+), have been demonstrated to play an important role in the process of aerobic granulation. Here, we studied whether iron ions can affect aerobic granulation. Granular sludge formed without iron ion addition (<0.02 mg Fe(2+) L(-1)) was fluffy and had a finger-type structure and filamentous out-growth. The addition of iron ions to concentrations of 1 and 10 mg Fe(2+) L(-1) repressed the finger-type structure and filamentous out-growth...
October 21, 2016: Biodegradation
Sunday A Adebusoye
Cupriavidus sp. strain SK-3, previously isolated on polychlorinated biphenyl mixtures, was found to aerobically utilize a wide spectrum of substituted aromatic compounds including 4-fluoro-, 4-chloro- and 4-bromobenzoic acids as a sole carbon and energy source. Other chlorobenzoic acid (CBA) congeners such as 2-, 3-, 2,3-, 2,5-, 3,4- and 3,5-CBA were all rapidly transformed to respective chlorocatechols (CCs). Under aerobic conditions, strain SK-3 grew readily on 4-CBA to a maximum concentration of 5 mM above which growth became impaired and yielded no biomass...
October 20, 2016: Biodegradation
N Fahrenfeld, A Pruden, M Widdowson
Methyl ethyl ketone (MEK) is a common groundwater contaminant often present with more toxic compounds of primary interest. Because of this, few studies have been performed to determine the effect of microbial community structure on MEK biodegradation rates in aquifer sediments. Here, microcosms were prepared with aquifer sediments containing MEK following a massive spill event and compared to laboratory-spiked sediments, with MEK biodegradation rates quantified under mixed aerobic/anaerobic conditions. Biodegradation was achieved in MEK-contaminated site sediment microcosms at about half of the solubility (356 mg/L) with largely Firmicutes population under iron-reducing conditions...
October 20, 2016: Biodegradation
Yonglan Tian, Huayong Zhang, Yang Chai, Lijun Wang, Xueyue Mi, Luyi Zhang, Maxwell Adam Ware
The importance of nickel (added as NiCl2) on mesophilic anaerobic fermentation of Phragmites australis straw and cow dung was demonstrated by investigating the biogas properties, pH values, organic matter degradation [chemical oxygen demand (COD)] and enzyme activities (cellulase, protease and dehydrogenase) during the fermentation process. The results showed that Ni(2+) addition increased the cumulative biogas yields by >18 % by improving the efficiency of first peak stage and bringing forward the second peak stage...
October 7, 2016: Biodegradation
Jennifer Z Menzies, Kathleen McDonough, Drew McAvoy, Thomas W Federle
The ultimate disposition of chemicals discarded down the drain can be substantially impacted by their fate in the sewer, but to date limited data have been published on the biodegradability of chemicals in sewer systems. The recently established OECD 314 guideline (Simulation tests to assess the biodegradability of chemicals discharged in wastewater, 2008) contains a simulation method (314A) for evaluating the biodegradation of chemicals in sewage under simulated sewer conditions. This research used the OECD 314A method to evaluate the rates and pathways of primary and ultimate biodegradation of a suite of (14)C-labeled homologues representing four classes of high volume surfactants including nonionic alkyl ethoxylates (AE), and anionic alkyl ethoxysulfates (AES), alkyl sulfate (AS) and linear alkyl benzene sulfonate (LAS)...
September 23, 2016: Biodegradation
Yuan Fang, Yao Du, Lifang Hu, Jing Xu, Yuyang Long, Dongsheng Shen
Hydrogen sulfide (H2S) is one of the major contributors to offensive odors from landfills, and its concentration differs under different operation modes. This study examined the distribution of H2S emission from different landfill depths under different operation modes (anaerobic, semi-aerobic, semi-aerobic transformation, and the three operation modes with additional leachate recirculation). The microbial community (especially the sulfur-metabolizing bacterial community) was investigated using high-throughput sequencing technology...
July 11, 2016: Biodegradation
Shu Zhang, Zhen Hou, Xiao-Ming Du, Dong-Ming Li, Xiao-Xia Lu
Site in a former chemical manufacture plant in China was found contaminated with high level of chlorinated volatile organic compounds (CVOCs). The major contaminants chloroform (CF), 1,2-dichloroethane (1,2-DCA) and vinyl chloride (VC) in groundwater were up to 4.49 × 10(4), 2.76 × 10(6) and 4.35 × 10(4) μg/L, respectively. Ethene and methane were at concentrations up to 2219.80 and 165.85 μg/L, respectively. To test the hypothesis that the CVOCs in groundwater at this site could be removed via biodegradation, biomarker analyses and microcosm studies were conducted...
June 28, 2016: Biodegradation
Zhaoming Zheng, Jun Li, Jing Ma, Jia Du, Wei Bian, Yun Li, Yanzhuo Zhang, Baihang Zhao
The simultaneous partial nitrification, anammox and denitrification (SNAD) process for treating domestic wastewater was investigated in a sequencing batch reactor (SBR). The SBR was operated with air flow rate of 500 L h(-1) at 30 °C. Domestic wastewater was used as influent and Kaldnes rings were used as biomass carriers. In the beginning, long aeration condition was implemented to cultivate nitrification biofilm. Afterwards, intermittent aerobic condition was conducted during the cycle operation. The influent organic matter loading rate was improved by reducing the aeration and mixing times...
June 21, 2016: Biodegradation
A M Ferro Orozco, E M Contreras, N E Zaritzky
As a result of its wide usage in the production of polycarbonate plastics and epoxy resins, bisphenol A (BPA) is commonly detected in wastewaters. Recently, BPA became a major concern because its adverse effects as an endocrine disruptor. In this work, the biodegradation kinetics of BPA and its metabolic intermediates 4-hydroxyacetophenone (4HAP), 4-hydroxybenzaldehyde (4HB) and 4-hydroxybenzoic acid (4HBA) by BPA-acclimated activated sludge was studied using manometric respirometry (BOD) tests. For all the tested compounds, BOD curves exhibited two phases...
June 9, 2016: Biodegradation
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