Characteristics of adsorbents made from biological, chemical and hybrid sludges and their effect on organics removal in wastewater treatment

For the upgrade and expansion of an existing caprolactam wastewater treatment plant, a freely floating sponge media (BioCube) process was selected based on extensive pilot-plant tests, due to extreme space constraints. In order to protect nitrifier inhibition caused by high strength organics in caprolactam wastewater, the pilot plant consisted of an organics removal reactor, which functioned as a pretreatment for nitrification, and followed the nitrogen removal reactor. The suspended MLSS was 1,800-4,000 and the media attached MLSS was maintained at 22,000-26,000 mg/L. The final effluent COD was noticeably low, around 20.4-37 mg/L, even with fairly large fluctuations in the feed levels, between 1,400-6,770 mg/L. The removal of total nitrogen with the system, when denitrification was close to completion, was approximately 97.6%. For the entire run, complete nitrification of 99.6% was achieved, which might have been due to well-acclimatized nitrifiers attached in the BioCube media. Specifically, after adaptation, the nitrification continuously increased in the organics removal reactor, even under high residual organics conditions. From the numerous experimental results, the BioCube process seemed to be an effective method for the upgrading and expansion of the existing wastewater treatment plant, with minimum reactor enlargement.

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Effects of Trichloroethylene on the Wastewater Treatment in Membrane Bioreactors

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.588-589.34 ◽

2012 ◽

Vol 588-589 ◽

pp. 34-38 ◽

Cited By ~ 1

Author(s):

Yuan Hong Ding ◽

Qing Wang ◽

Hong Qiang Ren ◽

Jian Lu

Keyword(s):

Wastewater Treatment ◽

Chronic Toxicity ◽

Membrane Bioreactors ◽

Ammonia Removal ◽

Membrane Reactors ◽

Nitrifying Bacteria ◽

Low Concentration ◽

Organics Removal ◽

Removal Efficiencies ◽

Sludge Activity

The activities of nitrifying bacteria and organic utilizing bacteria against TCE in sludge was investigated using three series of Membrane bioreactors, and the results indicated that, the removal efficiencies of COD decreased gradually, but was not affected severely with TCE inhibition, good organics removal efficiencies was possibly realized, while the ammonia removal efficiencies dropped sharply due to the severe inhibition of TCE against nitrifying bacteria, the degree of TCE inhibition against nitrifying bacteria increased with the TCE concentration, but low-concentration TCE addition seems act as a chronic toxicity to the sludge activity, However, the nitrifying bacteria was gradually adapted to the TCE inhibition and its activities could be entirely resumed, and the ability of the nitrifying sludge to tolerate TCE could be satisfactory maintained either after the stop of TCE addition, therefore, TCE could be degradated partly by the nitrification processes, when the TCE was added intermittently and continuously into the Membrane reactors, simultaneously, a good performance of nitrification and organic utilization processes was possibly maintained stably.

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ROLE OF PHYCOREMEDIATION IN DOMESTIC WASTEWATER TREATMENT

Water Conservation and Management ◽

10.26480/wcm.02.2021.53.57 ◽

2020 ◽

Vol 5 (2) ◽

pp. 53-57

Author(s):

Nandini Moondra ◽

Namrata D Jariwala ◽

Robin A Christian

Keyword(s):

Wastewater Treatment ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Domestic Wastewater ◽

Secondary Treatment ◽

Organics Removal ◽

Treated Effluent ◽

Domestic Wastewater Treatment

Conventional domestic wastewater treatment in most developing countries is confined to secondary treatments, mainly focusing on solids and organics removal, which results in eutrophication when the effluents are discharged into receiving bodies. Thus, to resolve the issues associated with the conventional treatment system, in the present study, microalgae was introduced in the primary treated effluent collected from a sewage treatment plant to study the efficiency of the system in reducing eutrophication and other challenges of secondary treatment. Phycoremediation is an effective and eco-friendly treatment alternative that reduced the primary-treated effluent’s PO4-P, NH3-N and COD concentration to 97.89%, 98.81%, and 88.24%, respectively at the identical HRT practiced for secondary treatment. One-way ANOVA was also conducted to determine the effectiveness of the system statistically. The experimental and statistical analysis proved that microalgal treatment could resolve the challenges of conventional secondary treatments if adopted for domestic wastewater.

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Hyperhaline Municipal Wastewater Treatment of a Processing Zone through Pilot-Scale A/O MBR, Part I: Characteristics of Mixture Liquor and Organics Removal

Procedia Environmental Sciences ◽

10.1016/j.proenv.2011.10.117 ◽

2011 ◽

Vol 8 ◽

pp. 773-780 ◽

Cited By ~ 2

Author(s):

Jingmei Sun ◽

Xiaohui Wang ◽

Ruixian Li ◽

LiFeng Dai ◽

Wen-ting Zhu

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Pilot Scale ◽

Municipal Wastewater Treatment ◽

Organics Removal ◽

Processing Zone

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Nitrifying biocathode enables effective electricity generation and sustainable wastewater treatment with microbial fuel cell

Water Science & Technology ◽

10.2166/wst.2009.209 ◽

2009 ◽

Vol 59 (9) ◽

pp. 1803-1808 ◽

Cited By ~ 6

Author(s):

Hung-Thuan Tran ◽

Dae-Hee Kim ◽

Se-Jin Oh ◽

Kashif Rasool ◽

Doo-Hyun Park ◽

...

Keyword(s):

Wastewater Treatment ◽

Fuel Cell ◽

Microbial Fuel Cell ◽

Power Density ◽

Treatment Plant ◽

Cell Voltage ◽

Maximum Power ◽

Maximum Power Density ◽

Organics Removal ◽

Sustainable Wastewater Treatment

Simultaneous organics removal and nitrification using a novel nitrifying biocathode microbial fuel cell (MFC) reactor were investigated in this study. Remarkably, the introduction of nitrifying biomass into the cathode chamber caused higher voltage outputs than that of MFC operated with the abiotic cathode. Results showed the maximum power density increased 18% when cathode was run under the biotic condition and fed by nitrifying medium with alkalinity/NH4+-N ratio of 8 (26 against 22 mW/m2). The voltage output was not differentiated when NH4+-N concentration was increased from 50 to 100 mg/L under such alkalinity/NH4+-N ratio. However, interestingly, the cell voltage rose significantly when the alkalinity/NH4+-N ratio was decreased to 6. Consequently, the maximum power density increased 68% in compared with the abiotic cathode MFC (37 against 22 mW/m2). Polarization curves demonstrated that both activation and concentration losses were lowered during the period of nitrifying biocathode operation. Ammonium was totally nitrified and mostly converted to nitrate in all cases of the biotic cathode conditions. High COD removal efficiency (98%) was achieved. In light of the results presented here, the application of nitrifying biocathode is not only able to integrate the nitrogen and carbon removal but also to enhance the power generation in MFC system. Our system can be suggested to open up a new feasible way for upgrading and retrofitting the existing wastewater treatment plant by the use of MFC-based technologies.

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Removal of Organic Matter by Physico-Chemical Mechanisms in Wastewater Treatment Plants

Water Science & Technology ◽

10.2166/wst.1993.0275 ◽

1993 ◽

Vol 27 (11) ◽

pp. 167-183 ◽

Cited By ~ 11

Author(s):

M. Boller

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Separation Performance ◽

Chemical Mechanisms ◽

Organics Removal ◽

Trace Organics ◽

Dissolved Organics ◽

Physico Chemical ◽

Solids Separation

Solids separation, adsorption onto participates and volatilization are the main physico-chemical mechanisms responsible for the removal of organic matter in wastewater treatment plants. In addition, solids separation as well as adsorption performance may be enhanced by chemical flocculation/precipitation with hydrolyzing metal salts. With the help of particle size distributions and other characteristics of the particulates at different treatment stages, more insight can be gained into the interactions between paniculate properties and solids separation performance. Significant removal of trace organics is achieved by adsorption onto paniculate surfaces and stripping in aeration tanks. Examples illustrate the adsorption of the relatively large quantities of substances contained in detergents and reveal the effect on water and sludge quality. Octanol/water partition coefficients of trace organics may be used together with oxygen transfer characteristics to determine the potential of volatilization into the air. The effect of flocculants on paniculate and dissolved organics removal in wastewater treatment is illustrated when Fe-salts are dosed to raw sewage, to the biological stage or to tertiary filters.

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