Simultaneous activated sludge wastewater treatment and odour control

Lab-scale tests were used to determine the amount of H2S that can be treated using a range of different activated sludges. Static vessels were used to study the effects of different H2S concentrations (5, 25, 50 and 75 ppm). The data indicated that odour control may be carried out using certain types of sludge, but sludge type, e.g. carbonaceous, nitrifying, with or without coagulant, affects removal efficiency. The presence of the biomass resulted in greater H2S removal than the use of wet scrubbing and the adverse effects on mixed liquor were negligible. A pilot plant was used to study the removal efficiencies of activated sludge diffusion using a typical wastewater treatment plant H2S concentration and investigated the effects that the diffusion of H2S had on the process performance. Results indicated that the levels of H2S produced by other unit processes on a wastewater treatment site (approximately 5 ppm) can be treated using activated sludge diffusion without compromising the performance of the wastewater treatment process. The only effects on the activated sludge plant observed were: (1) nitrification was interrupted briefly as H2S diffusion commenced and (2) the species' diversity in the sludge decreased.

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A study on the effects of ozone dosage on dissolved-ozone flotation (DOF) process performance

Water Science & Technology ◽

10.2166/wst.2015.115 ◽

2015 ◽

Vol 71 (9) ◽

pp. 1423-1428 ◽

Cited By ~ 7

Author(s):

Xin Jin ◽

Pengkang Jin ◽

Xiaochang Wang

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Treatment Process ◽

Treatment Plant ◽

Pilot Scale ◽

Secondary Effluent ◽

Process Performance ◽

Wastewater Treatment Process ◽

Organic Matter Removal

Dissolved-ozone flotation (DOF) is a tertiary wastewater treatment process, which combines ozonation and flotation. In this paper, a pilot-scale DOF system fed by secondary effluent from a wastewater treatment plant (WWTP) in China was used to study the effect of ozone dosage on the DOF process performance. The results show that an ozone dosage could affect the DOF performance to a large extent in terms of color and organic matter removal as well as disinfection performance. The optimal color and organic matter removal was achieved at an ozone dosage of 0.8 mg/l. For disinfection, significant improvement in performance could be achieved only when the organic matter removal was optimal. The optimal ozone dosage of at least 1.6 mg/l was put forward, in this case, in order to achieve the optimal color, turbidity, organic matter and disinfection performance.

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Possible impact of treated wastewater discharge on incidence of antibiotic resistant bacteria in river water

Water Science & Technology ◽

10.2166/wst.2001.0077 ◽

2001 ◽

Vol 43 (2) ◽

pp. 91-99 ◽

Cited By ~ 79

Author(s):

T. Iwane ◽

T. Urase ◽

K. Yamamoto

Keyword(s):

Wastewater Treatment ◽

River Water ◽

Wastewater Treatment Plant ◽

Treatment Process ◽

Treatment Plant ◽

Treated Wastewater ◽

Resistant Bacteria ◽

Wastewater Discharge ◽

Wastewater Treatment Process ◽

Antibiotic Resistant

Escherichia coli and coliform group bacteria resistant to seven antibiotics were investigated in the Tama River, a typical urbanized river in Tokyo, Japan, and at a wastewater treatment plant located on the river. The percentages of antibiotic resistance in the wastewater effluent were, in most cases, higher than the percentages in the river water, which were observed increasing downstream. Since the possible increase in the percentages in the river was associated with treated wastewater discharges, it was concluded that the river, which is contaminated by treated wastewater with many kinds of pollutants, is also contaminated with antibiotic resistant coliform group bacteria and E.coli. The percentages of resistant bacteria in the wastewater treatment plant were mostly observed decreasing during the treatment process. It was also demonstrated that the percentages of resistance in raw sewage are significantly higher than those in the river water and that the wastewater treatment process investigated in this study works against most of resistant bacteria in sewage.

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Sensitivity analysis of a municipal wastewater treatment plant model

MATEC Web of Conferences ◽

10.1051/matecconf/201925205010 ◽

2019 ◽

Vol 252 ◽

pp. 05010

Author(s):

Paweł Król ◽

Alberto Gallina ◽

Michał Lubieniecki ◽

Tadeusz Uhl ◽

Tadeusz Żaba

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Treatment Process ◽

Biological Process ◽

Treatment Plant ◽

Numerical Procedure ◽

Municipal Wastewater Treatment ◽

Wastewater Treatment Process ◽

Plant Model ◽

The Relationship

Waste management is a crucial process to keep the environment in wholesome conditions. The environmental impact of solid waste and wastewater is reduced through construction of appropriate disposal installations. The objective of wastewater treatment in biological reactors is to control the process of biomaterial growth by aerating the sewage content. The process is complex, as depending on a plenty of parameters. In the last decades an effective numerical model, called the Activated Sludge Model (ASM), has been proposed for describing the biological process. The ASM is implemented in the Benchmark Simulation Model (BSM) that simulates the whole wastewater treatment process. The most important parameters in ASM are the kinetic and stoichiometric coefficients. The former describes rate-concentration dependence. The latter characterises the relationship between the components of chemical reactions taking place in the cleaning process. Above parameters are determined by on-site calibration and their importance is relevant during the development of numeric models. This paper aims to examine the influence of kinetic and stoichiometric parameters on the wastewater treatment process of a plant in Płaszów, Kraków. The analysis is carried out by a sample-based numerical procedure. It highlights the ASM parameters playing a major role in the treatment process. Results obtained from the analysis are important for future validation and optimisation processes.

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Unravelling diversity and metabolic potential of microbial consortia at each stage of leather sewage treatment

RSC Advances ◽

10.1039/c7ra07470k ◽

2017 ◽

Vol 7 (66) ◽

pp. 41727-41737 ◽

Cited By ~ 5

Author(s):

Hebin Liang ◽

Dongdong Ye ◽

Lixin Luo

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Treatment Process ◽

Sewage Treatment ◽

Microbial Consortia ◽

Biological Wastewater Treatment ◽

Metabolic Potential ◽

Ecological Functions ◽

Wastewater Treatment Process ◽

System P

Activated sludge is essential for the biological wastewater treatment process and the identification of active microbes enlarges awareness of their ecological functions in this system.

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Insight into removals of PARAFAC components from dissolved and particulate organic matter in wastewater treatment process by two-dimensional correlation and structure equation modeling

Environmental Sciences Europe ◽

10.1186/s12302-021-00558-z ◽

2021 ◽

Vol 33 (1) ◽

Author(s):

Benxin Yu ◽

Dongping Liu ◽

Jian Wang ◽

Yingxue Sun

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Particulate Organic Matter ◽

Structural Equation ◽

Treatment Process ◽

Treatment Plant ◽

Equation Modeling ◽

Two Dimensional ◽

Wastewater Treatment Process ◽

Insight Into

Abstract Background Most particulate organic matter (POM) cannot be directly degraded in the conventional wastewater treatment, which should be transformed into dissolved organic matter (DOM) through a hydrolysis process. However, non-hydrolyzed POM in the biological treatment can limit treated efficiencies for the wastewater treatment plants (WWTPs) facilities. Hence an operational tool is indispensable for insight into removals of DOM and POM factions in the WWTP. In this study, excitation-emission matrix fluorescence spectroscopy (EEM) combined parallel factor analysis (PARAFAC), two-dimensional correlation (2D-COS) and structural equation modeling (SEM) was employed to evaluate removals of DOM and POM in a wastewater treatment plant. Results Four fluorescence components were identified in DOM and POM substances from the WWTP by EEM combined with PARAFAC, i.e., tyrosine-like (TYLF), tryptophan-like (TRLF), microbial byproduct-like (MBLF), and fulvic acid-like (FALF). In A2/O process, the TYLF and TRLF of DOM were removed to a larger extent than those of MBLF and FALF in anaerobic tank, while TYLF and MBLF of POM were removed to a great extent than those of TRLF and FALF in primary sedimentation and aerobic tanks. By the 2D-COS, a decreasing variation order of DOM fractions in the wastewater treatment process was UV-FALF → MBLF2 → Vis-FALF → TRLF → TYLF, while the decreasing order of POM fractions was Vis-FALF → UV-FALF → MBLF2 → TYLF → MBLF1 → TRLF. SEM revealed that TRLF and TYLF of DOM were degraded by anaerobic microorganism, and TRLF could be transformed partially into FALF. However, TRFL and TYLF of POM were discomposed by aerobic microorganism. Conclusions The 2D-COS and SEM can be practicable tools as EEM-PARAFAC for monitoring DOM and POM in the WWTP. The study could present a theoretical support to improving the retrofit of WWTP and formulating emission standards for organic pollutants.

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