scholarly journals Engineered electrocoagulation reactor for the removal of E. coli from wastewaters

2021 ◽  
Vol 877 (1) ◽  
pp. 012048
Author(s):  
Eman A. Al-Imara ◽  
Rand L. Al-Jaryan ◽  
Sabrean F. Jawad ◽  
Mohanad M. Kareem ◽  
Hayfaa A. Mubarak

Abstract As a consequence of natural pollution, water and sewage are polluted in many nations across the globe. Especially in poorer countries, sewage treatment and disposal practices are often substandard. Throughout many limited-income nations, the poor economic condition and absence of resources assistance severely hamper the planning and application of novel water and sewage systems. This has resulted in a rise in the number of bio-contaminants in the environment. The objective of this study is to use electrocoagulation as a low-cost method to remove or lower the amount of bio contaminant in sewage. By transmitting a voltage between the two conductors, disinfectants are generated in place. Sewerage samples were obtained at the Kerbala wastewater treatment plant, which is situated south of Kerbala, Iraq. In this work, steel plates were utilized to create coagulants. Furthermore, the effect of many factors on the performance of the electrolysis device was studied, namely spacing among electrodes and current density. The analysis indicates after 40 min of irradiation employing electrodes spaced 5mm apart and a current intensity of 2 mA/cm2, the E. coli bacteria as a biocontrol agent were killed. Furthermore, the results demonstrated that an initial pH value of 6.0 is appropriate for bio-contaminants removal utilizing electrocoagulation.

2011 ◽  
Vol 474-476 ◽  
pp. 158-161 ◽  
Author(s):  
Jin Yong Liu ◽  
Xu Nan Ning ◽  
Zuo Yi Yang

Sewage sludge incineration residue was obtained from a sewage treatment plant in Guangzhou and used as a low-cost sorbent for removing Ni2+ from wastewaters. The adsorption effectiveness and their factors of Ni2+ in aqueous solutions were simulated detailed using the adsorbents of the sludge incineration residue. The simulation contents and the factors included the adsorption time, the pH of solution and the dosage of adsorbents and so on. The results showed that at room temperature, the adsorption equilibrium of Ni2+ can be achieved in 6h and the best pH value of the solution was about 7.0. The removal rates of Ni2+ were increased with the adsorbent concentration increasing and the optimal concentration of adsorbent was 10g/L with the initial concentration of Ni2+ less than 30mg/L.At the best adsorption conditions, the removal rate of Ni2+ reached more than 70%.


2011 ◽  
Vol 55-57 ◽  
pp. 308-311 ◽  
Author(s):  
Jing Yong Liu ◽  
Shui Yu Sun ◽  
Rong Xue Zhang ◽  
Sheng Zhong ◽  
Min Ting Chen

Sewage sludge incineration slag, the waste generated in sewage sludge incineration, was obtained from a sewage treatment plant in Guangzhou and used as a low-cost sorbent for removing Cu(Ⅱ) from wastewaters. The adsorption effectiveness and their factors of Cu2+ in aqueous solutions were simulated detailed using the adsorbents of the sludge incineration slag. The simulation contents and the factors included the adsorption time, the pH of solution and the dosage of adsorbents and so on. The results showed that at 30 °C, the adsorption equilibrium of Cu2+ can be achieved in 6h and the best pH value of the solution was about 4.5-5.5. The removal rates of Cu2+ were increased with the adsorbent concentration increasing and the optimal concentration of adsorbent was 20-30g/L with the initial concentration of Cu2+ less than 25mg/L.At the best adsorption conditions, the removal rate of Cu2+ reached more than 80% and the adsorption capacity was 0.83-1.25mg/g.


2019 ◽  
Vol 3 (1) ◽  
pp. 27 ◽  
Author(s):  
Samir Tayar ◽  
Renata Guerrero ◽  
Leticia Hidalgo ◽  
Denise Bevilaqua

The packing material selection for a bioreactor is an important factor to consider, since the characteristics of this material can directly affect the performance of the bioprocess, as well as the investment costs. Different types of low cost packing materials were studied in columns to reduce the initial and operational costs of biogas biodesulfurization. The most prominent (PVC pieces from construction pipes) was applied in a bench-scale biotrickling filter to remove the H2S of the biogas from a real sewage treatment plant in Brazil, responsible for 90 thousand inhabitants. At the optimal experimental condition, the reactor presented a Removal Efficiency (RE) of up to 95.72% and Elimination Capacity (EC) of 98 gS·m−3·h−1, similar to open pore polyurethane foam, the traditional material widely used for H2S removal. These results demonstrated the high potential of application of this packing material in a full scale considering the robustness of the system filled with this support, even when submitted to high sulfide concentration, fluctuations in H2S content in biogas, and temperature variations.


2015 ◽  
Vol 733 ◽  
pp. 334-337
Author(s):  
Ang Li ◽  
Li Na Sun

By aerobic composting bin type of sewage treatment plant sludge composting, through periodic sampling, research composting process temperature, moisture content, PH value changes and study the changes in compost maturity parameters of the DH. The results show that the compost temperature increased rapidly in the early rise in the first two days when fast to 50 degrees Celsius, in the tenth day decreased to room temperature; moisture content than the original sludge reduced by 40 percent to compost indicators; PH by reaction initial 6.2, and gradually becomes neutral and alkaline 7.8 biased. Experiments show that after aerobic sludge composting in temperature, moisture content, PH value terms have been reached sludge disposal requirements.


2004 ◽  
Vol 70 (6) ◽  
pp. 3535-3540 ◽  
Author(s):  
Cristina Garc�a-Aljaro ◽  
Maite Muniesa ◽  
Juan Jofre ◽  
Anicet R. Blanch

ABSTRACT Shiga toxin-producing Escherichia coli strains are human pathogens linked to hemorrhagic colitis and hemolytic uremic syndrome. The major virulence factors of these strains are Shiga toxins Stx1 and Stx2. The majority of the genes coding for these toxins are borne by bacteriophages. Free Stx2-encoding bacteriophages have been found in aquatic environments, but there is limited information about the lysogenic strains and bacteria present in the environment that are susceptible to phage infection. The aim of this work was to study the prevalence and the distribution of the stx 2 gene in coliform bacteria in sewage samples of different origins. The presence of the stx 2 gene was monitored every 2 weeks over a 1-year period in a municipal sewage treatment plant. A mean value of 102 genes/ml was observed without significant variation during the study period. This concentration was of the same order of magnitude in raw municipal sewage of various origins and in animal wastewater from several slaughterhouses. A total of 138 strains carrying the stx 2 gene were isolated by colony hybridization. This procedure detected approximately 1 gene-carrying colony per 1,000 fecal coliform colonies in municipal sewage and around 1 gene-carrying colony per 100 fecal coliform colonies in animal wastewaters. Most of the isolates belonged to E. coli serotypes other than E. coli O157, suggesting a low prevalence of strains of this serotype carrying the stx 2 gene in the wastewater studied.


2006 ◽  
Vol 50 (7) ◽  
pp. 2433-2438 ◽  
Author(s):  
M. Lavollay ◽  
K. Mamlouk ◽  
T. Frank ◽  
A. Akpabie ◽  
B. Burghoffer ◽  
...  

ABSTRACT One hundred twenty CTX-M-15-producing Escherichia coli strains isolated in 10 different hospitals from Paris (France), in the Hospital Charles Nicolle in Tunis (Tunisia), and in the Pasteur Institute in Bangui, Central African Republic (CAR), between 2000 and 2004 were studied. Eighty isolates, recovered from the three countries, were clonally related by repetitive extragenic palindromic PCR and pulsed-field gel electrophoresis. Various resistance profiles were identified among these clonal strains. After conjugation or electroporation of plasmids from E. coli strains representative of each profile and each geographic region, we observed seven resistance profiles in the recipient strains. Incompatibility typing showed that all the plasmids transferred from the clonal strains studied, except one, belonged to the incompatibility group FII. They all shared a multidrug resistance region (MDR) resembling the MDR region located in pC15-1a, a plasmid associated with an outbreak of a CTX-M-15-producing E. coli strain in Canada. They also shared the common backbone of an apparent mosaic plasmid, including several features present in pC15-1a and in pRSB107, a plasmid isolated from a sewage treatment plant. This study suggests that although the plasmid-borne bla CTX-M-15 gene could be transferred horizontally, its dissemination between France, Tunisia, and CAR was due primarily to its residence in an E. coli clone with a strong propensity for dissemination.


Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Tianbo Liang ◽  
Linjie Shao ◽  
Erdong Yao ◽  
Jie Zuo ◽  
Xiongfei Liu ◽  
...  

Hydraulic fracturing requires a large volume of fresh water, which is difficult and expensive to obtain in the desert area such as Tarim Basin. Currently, flowback fluid is typically transported to the sewage treatment plant and then discharged after reaching environmental requirements; however, this is not only costly, but also a waste of water resource. Therefore, it is imperative to understand the potential interactions between fracturing fluid and reservoir rock, and then find solutions to reuse the flowback water for subsequent fracturing. In this study, once flowback fluid was directly collected from the field, its chemical compositions were analyzed; then, filtering, decoloring, and chelating methods were chosen to effectively remove or shield the unfavorable reintroduced components. Moreover, pH value was further tuned during different stages of the recycling process to ensure good gelation and cross-linking properties of guar. Cross-linked guar synthesized with the flowback fluid was evaluated in the lab through shear resistance tests and coreflood tests under the reservoir conditions; results indicated the recycled gel behaved similarly as the original gel, or even better. From this work, a cheap and effective treatment process was proposed to reuse the flowback fluid in the desert area.


In the present investigation , neem leaves are obtained from the agricultural fields and its potential for the removal of dye is tested with the model system of methylene blue in water . The MB has health hazards, its been reported that exposures to the dyes cause allergic reactions, and hence its reflected as toxic. The results obtained from batch experiments are quite useful in giving information about the efficacy of dye-adsorbent system. The influence of factors such as the initial pH value, adsorbent dose, and time of contact was investigated. The results indicate that the percentage removal also increased with the rise in the adsorption capacity (qe). 82% of colour elimination can be obtained at the dose of 100g/l NLP for methylene blue of 10mg/l concentration. The optimal parameters for this experiment were 10mg/l for initial dye concentration, 5gm/50ml adsorbent dosage and pH 8. In the batch system, the adsorption capacity was increased when the parameters were increased until it achieved the equilibrium. Langmuir adsorption isotherm graphics plotted with l/qevis 1/Ce. Trend lines for the adsorption data of different concentration of methylene blue with neem leave as adsorbent is plotted. The linear regression was piloted using plot l/qevis 1/Ce; it was found that R2 value are quite closer to 1 signifying Langmuir isotherm as a good fit for this experimental data. Results indicated that neem leaves has potential to remove Methylene Blue Dye from aqueous streams and can be successfully used as a low cost adsorbent.


1989 ◽  
Vol 21 (10-11) ◽  
pp. 1447-1451 ◽  
Author(s):  
Peter Thomas Ruggenthaler

The sewage treatment plant at Simmering, Vienna, has been operating since June 1980, together with the ‘EbS' plant for sludge treatment and disposal. This latter consisted of centrifuges, grinder dryers and fluidised bed incineration but due to difficulties with the grinder dryers it has never operated efficiently. Accordingly trials have been done using improved centrifuges and filter presses to increase the dry solids content of the cake fed to the incinerators without using the grinder dryers. It was found that all systems tried were an improvement on the existing but that the best result was achieved using a Centripress on preheated sludge conditioned by polyelectrolyte. The plant was converted to this system in 1987 and results of full-scale operation as well as test results are given in the paper.


2006 ◽  
Vol 1 (3) ◽  
Author(s):  
Dong-Jin Ju ◽  
Im-Gyu Byun ◽  
Chang-Han Lee ◽  
Gab-Hwan An ◽  
Tae-Joo Park

This study examined the removal of reactive dye onto dead cells in activated sludge collected from the municipal sewage treatment plant in Suyoung, Pusan. The biosorption of reactive dye from aqueous solutions using the activated sludge was studied using a batch system with respect to the initial pH, temperature, amount of adsorbent and the pre-treatment of the adsorbent. Both the Freundlich and Langmuir isotherm models could describe the adsorption equilibrium of the reactive dye onto the activated sludge with the Langmuir isotherm showing the best agreement. First- and second-order kinetic models were used to investigate the adsorption mechanism. The adsorption capacity of Rhodamine-B(Rh-B) onto the activated sludge increased with decreasing initial pH and temperature.


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