Physico-chemical and Microbiological Qualities of Abattoir Wastewater in Egbu, Imo State, Nigeria

Abbattoir waste water is of a complex composition. When discharged without being treated, poses a threat to human health and the environment. This is the practice common in Nigeria, and is worrisome.Objective: The aim of this study was to assess the physico-chemical and microbiological qualities of waste water from Egbu abattoir discharged into ‘Otamiri’ river in Owerri North local government area, Imo State, Nigeria.Methods: The microbial quality of abattoir wastewater was studied. The duration of the study was three months, from June to September, 2019. Sample collection was done in the morning (8-10am) and in the evening (4-6pm). A total of thirty samples (30) were collected from two sampling points, at the place of generation of the wastewater (Effluent source) and at the point of discharge into the river (POE). Standard methods were employed to assess the microbiological and physiochemical quality of the effluent. The microorganisms isolated from the samples included Escherichia coli, Salmonella, Staphylococcus, Aspergillus, Mucor, Listeria, Micrococcus and Candida species. The Total Heterotrophic Count (THC) of effluent samples, at source and POE were 8.51log10 cfu/ml and 6.15log10cfu/ml respectively, Total Coliform Count (TCC) for same samples were 6.77log10 cfu/ml and 4.56log10 cfu/ml respectively. The Total Fungal Count (TFC) of the effluent samples at source and at POE was 5.19log10 cfu/ml and 4.18log10 cfu/ml respectively. Results further revealed that the pH of the effluent at source was 6.58 while that at Point of Entry into the river was 7.30. The temperature of both samples was 25oC. The Total Dissolved Solid values of the effluent collected at source was higher, having a value of 1400mg/L against 1000mg/L at Point of Entry. Also the Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) values of the effluent at source were 5.10mg/L and 8.58mg/L respectively, while the BOD and COD of the water at the POE were 4.3mg/L and 7.9mg/L respectively.Conclusion: Abattoir wastes are becoming a major environmental health challenge and being discharged into the Otamiri River indiscriminately is of public health concern. The potential public health implications associated with discharging untreated abattoir wastewater into the environment and thus, the need for adequate treatment to ensure decontamination as well as providing wastewater treatment facility is imperative.

Insights into the microbial community structure of anaerobic digestion of municipal solid waste landfill leachate for methane production by adaptive thermophilic granular sludge

BACKGROUND: The amount of municipal solid waste (MSW) gradually increased along with the rapid development of modern cities. A large amount of landfill leachate are generated with excessive chemical oxygen demand (COD), which create a great deal of pressure on the environment-friendly treatment process. Anaerobic digestion is an ideal technique to solve the above problem. RESULTS: A thermophilic granular sludge was successfully adapted for anaerobic digestion of MSW leachate (from an aging large-scale landfill) for methane production. The COD degradation efficiency improved by 81.8%, while the methane production rate reached 117.3 mL CH4/(g VS d), which was 2.34-fold more than the control condition. The bacterial and archaeal communities involved in the process were revealed by 16S rRNA gene high-throughput pyrosequencing. The richness of the bacterial community decreased in the process of thermophilic granular sludge, while the archaeal community structure presented a reverse phenomenon. The bacterial genus, Methanosaeta was the most abundant during the mesophilic process, while Methanobacterium, Methanoculleus, Methanosaeta and Methanosarcina were more evenly distributed. The more balanced community distribution between hydrogenotrophic and acetotrophic methanogens implied a closer interaction between the microbes, which further contributed to higher methane productivity. The detailed relationship between the key functional communities and anaerobic digestion performances were demonstrated via the multivariate canonical correspondence analysis. Conclusions: With the assistance of adaptive thermophilic granular sludge, microbial community structure was more evenly distributed, while both of COD degradation rate and methane production was improved during anaerobic digestion of MSW landfill leachate.

Feasibility Analysis of Removal of Alkaloids from Processing Wastewater of Aconiti Radix by Flocculation / 中国实验方剂学杂志

Objective: To investigate the removal effect of 5 kinds of common flocculants on 6 kinds of toxic alkaloids in processing wastewater of Aconiti Radix. Method: HPLC was employed to determine contents of 6 kinds of alkaloids in the processing wastewater of Aconiti Radix before and after flocculation.The mobile phase consisted of acetonitrile-tetrahydrofuran(25:15)-0.1 mol·L-1 ammonium acetate solution(each 1 L contains 0.5 mL of glacial acetic acid) for gradient elution, volume flow rate was 1.0 mL·min-1, detection wavelength was 235 nm.The removal characteristics and effects of five common flocculants of ferric chloride, aluminum sulfate, polymeric ferric sulfate, polyaluminum chloride/polyacrylamide(PAC/PAM) and sodium polyacrylate were compared and preliminarily optimized. Result: The 5 kinds of flocculants had certain selectivity for different types of alkaloids, and the removal of 6 kinds of alkaloids showed obvious differences.Among them, the PAC/PAM attenuated relative superiority, when the pH 6, adding amount of 0.25 g·L-1 and PAC-PAM dosing ratio of 30:1, comprehensive removal effect was relatively good, removal rates of mesaconitine and hypaconitine was 85.4%and 58.3%, respectively. Conclusion: The flocculation method can be used as a pretreatment process to reduce the toxicity of processing wastewater of Aconiti Radix.

A Point of Care Testing System for Chemical Oxygen Demand Based on Graphene Oxide-Nickel Nanoparticles Modified Electrode / 分析化学

An electrochemical analysis system for rapid determination of chemical oxygen demand ( COD) in flow state was established. A planar electrode modified with GO-NiNPs was matched with a 3D printed thin-layer cell. The sample was driven smoothly through the electrode surface by a micro peristaltic pump and then measured by chronoamperometry. The effect of modified materials, dielectric and electrochemical operating conditions were investigated. The whole response time of COD was 1. 5 min and the demand for the sample was about 2 mL. It turned out that the linear range of response in the low concentration region was 0. 15-100 mg/L, the linear equation was i(μA)=3. 974c (mg/L)+0. 2295 (r = 0. 9991) and the detection limit was 0. 04 mg/L. The linear response range in the high concentration region was 100-450 mg/L, and the linear equation was i(μA)=1. 938c (mg/L)+ 230. 9 (r = 0. 9877). Compared with the national standard method (GB11914-89) for measuring the actual water samples (Qinhuai River, Xuanwu Lake and Nanjing tap water), the correlation between them was quite good and the analysis time was dropped to 1/100. This new sensing system provided an environmentally friendly and portable method for detection of COD without using expensive, highly corrosive and toxic reagents.

Delineamento Box-Behnken para remoção de DQO de efluente têxtil utilizando eletrocoagulação com corrente contínua pulsada / Box-Behnken design for COD removal of textile wastewater using electrocoagulation with pulsed DC

RESUMO A remoção de poluentes de efluentes industriais de forma efetiva e economicamente viável ainda é um desafio. Dessa forma, o presente trabalho propôs investigar a tecnologia de eletrocoagulação (EC) para o tratamento de efluente têxtil utilizando corrente contínua pulsada (CCP). A metodologia de superfície de resposta Box-Behnken foi utilizada para analisar e otimizar as condições operacionais, visando à máxima remoção de demanda química de oxigênio (DQO). Os experimentos foram realizados com um volume reacional de 2,6 L, em modo batelada. Diante dos resultados obtidos, a configuração ótima considerada foi: velocidade de agitação = 200 rpm, frequência dos pulsos = 1.000 Hz e espaçamento entre os eletrodos = 1 mm, em 50 minutos de EC. Nessas condições foi obtida uma remoção de DQO de 81,23% (valor remanescente de 152 mg O2.L-1). Em adição, verificou-se que o processo de EC também é eficaz para a redução de cor, turbidez, sólidos suspensos totais, sulfato e sulfeto. A concentração de íons cloreto não foi alterada durante a EC, apresentando-se como um aspecto favorável para a reutilização do efluente tratado no próprio processo produtivo têxtil, o qual demanda uma elevada concentração de NaCl.

ABSTRACT The effective and economically viable removal of industrial wastewater pollutants is still a challenge. Thus, this study proposed to investigate the electrocoagulation technology (EC) for the treatment of textile effluent using pulsed direct current (CCP). The methodology of Box-Behnken response surface was used to analyze and optimize the operating conditions, aimed at maximum chemical oxygen demand (COD) removal. The experiments were performed with a reaction volume of 2.6 L in batch mode. Based on these results, the optimal configuration was: agitation speed = 200 rpm, frequency of pulses = 1,000 Hz and spacing between electrodes = 1 mm, in 50 minutes of EC. Under these conditions it was obtained a COD removal of 81.23% (remainder value of 152 mg O2.L-1). In addition, it was found that the EC process is also effective for reduction of color, turbidity, total suspended solids, sulfate and sulfide. The concentration of chloride ions was not modified during the EC, presenting itself as a favorable aspect for the reuse of treated wastewater in the textile production process itself, which demands a high concentration of NaCl.

Reator anaeróbio tipo UASB conjugado com processo Fenton para remoção de cor e demanda química de oxigênio de água residuária sintética de indústria têxtil / Anaerobic reactor type UASB conjunction with process Fenton to remove color and chemical oxygen demand textile industry of synthetic wastewater

RESUMO A contaminação por despejos de efluentes industriais têxteis tem sido uma preocupação emergente de pesquisadores e ambientalistas, pois esses apresentam composição extremamente heterogênea e grande quantidade de material tóxico e recalcitrante, o que dificulta seu tratamento. Durante o processamento têxtil, uma ampla gama de corantes é liberada e alguns desses, como os azo corantes, que se caracterizam pela função azo (-N=N-) ligada a grupos aromáticos e podem ser tóxicos, carcinogênicos e/ou mutagênicos. Em vista disso, esta pesquisa teve como principal objetivo avaliar os benefícios da utilização de um reator anaeróbio tipo reator anaeróbico de fluxo ascendente com manta de lodo (UABS), seguido de processo oxidativo avançado (POA) do tipo Fenton na degradação de cor e demanda química de oxigênio (DQO) de efluente sintético de indústria têxtil. Com os resultados, foram verificadas remoções de DQO em torno de 82,0% para o reator UASB e de 95,6% para o conjunto. A cor alcançou 96,1% de remoção no reator UASB e 100,0% ao final do processo.

ABSTRACT Contamination by textile industrial wastewater discharges has been an emerging concern of researchers and environmentalists, as they have extremely heterogeneous composition and loads of toxic and recalcitrant material, which complicates treatment. In the textile processing, a wide range of dye is released and some of these, such as dyes, azo, characterized by the feature azo (-N=N-) attached to aromatic groups and may be toxic, carcinogenic and/or mutagenic. In view of this, this research aimed to evaluate the benefits of using an anaerobic reactor type anaerobic reactor upflow sludge blanket (UABS), followed by advanced oxidation process (AOP) type Fenton in color degradation and chemical oxygen demand (COD) of synthetic textile industry effluent. From the results of COD removal was observed at around 82.0% for the UASB reactor and 95.6% for the group. The color reached 96.1% removal in UASB reactor and 100.0% at the end of the process.

Biodegradation of deproteinized potato wastewater and glycerol during cultivation of Rhodotorula glutinis yeast

Background Deproteinized potato wastewater and glycerol are two by-products which are difficult to dispose. The objective of this study was to determine the ability of Rhodotorula glutinis to use glycerol and nitrogen compounds present in deproteinized potato wastewater and to evaluate the ability of simultaneous biodegradation of potato wastewater and glycerol via microbiological methods. Results It has been found that R. glutinis used glycerol and potato wastewater as a source of carbon and nitrogen, respectively. The highest degree of glycerol content (70.6%) reduction was found after cultivation of the investigated strain using a medium with 5% glycerol. In this medium, a significant reduction in the total protein content, estimated at 61%, was observed. The process of 72 h cultivation of yeast in a medium containing potato wastewater and 5% glycerol reduced the chemical oxygen demand (COD) more than 77%. Supplementation of media with high doses of glycerol (i.e. 20 and 25%) led to decreased metabolic activity in the yeast strain tested. Conclusion It has been found that there is a possibility of simultaneous biodegradation of potato wastewater and glycerol during the cultivation of R. glutinis.

Phytoremediation of Textile Waste Water Using Potential Wetland Plant: Eco Sustainable Approach.

One of the major problems encountered in the textile industry is the production of large volumes of highly coloured wastewater. The textile industries daily discharge million litres of untreated effluents in the form of wastewater into public drains that eventually empty into rivers. They cause serious health hazard. Textile wastewater also contains substantial pollution loads which increase the Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), Total Suspended solids (TSS), Total Dissolved Solids (TDS) and heavy metals. So pre-treatment is needed prior to discharge of these effluents. Among all method investigated presently, Phytoremediation by AMATS (Aquatic Macrophytes Treatment Systems) is a well established environmental protective technique. The most common aquatic Macrophytes being employed in wastewater treatment are water hyacinth, penny wort, water lettuce, water ferns and duck weeds, because they are cheaper to construct and a little skill is required to operate them. This review paper discusses comparative study and efficiency of plants and proposed mechanism of various plant contributed for remediation of textile waste water.

Use of Palm Oil Mill Effluent as Medium for Cultivation of Chlorella sorokiniana.

Aims: Palm oil mill effluent (POME) erodes the principal biophysical characteristic of both soil and water when discharged untreated but could be exploited as medium for microalgae cultivation due to its vast mineral contents. Place and Duration of study: POME samples were collected from a local palm oil processing mill at Nsukka, Enugu State, Nigeria. A part of the study was done at the Graduate School of Life and Environmental Sciences, University of Tsukuba, Japan while the rest at the University of Nigeria, Nsukka between March and September, 2012. Methodology: Chlorella sorokiniana C212 was grown in several Batches (A-D) of POME supplemented with urea (60 mg/L) before subjecting to different sterilization protocols. Cultivation was conducted in shaker flasks at 150 rpm, 1 vvm, 3000 lux and pH 7.0±0.2. Results: The filter sterilized Batch (B) promoted the highest (1070±30 mg/L) dry cell weight (DCW), lipid (156±12 mg/g-cell) and chlorophyll (1.59±0.11 mg/g-cell) contents while chemical oxygen demand (COD) decreased by 45±08%. The autoclaved medium (Batch A) gave the least DCW (310±20 mg/L), lipid production (40±05 mg/g-cell) and chlorophyll content (0.58±0.02 mg/g-cell) while COD reduced by 20±04%. The highest COD decrease (70±05%) was achieved in the unsterilized Batch (D). Batch B was most positively affected by dilution because at 75% concentration, DCW increased to 1360±30 mg/L, lipid contents to 174±10 mg/g-cell, chlorophyll to 1.87±0.14 mg/g-cell the while COD declined by 63±03%. Conclusions: POME has potential for use in microalgae cultivation with significant saving in treatment costs.

Municipal wastewater treatment and kinetic studies using immobilized fixed bed anaerobic digester.

This study was designed to evaluate the performance of a cylindrical immobilized fixed Bed. Anaerobic digester in treating diluted municipal waste water. A series of three independent batch experiments was performed for a total operation time of 28 days. The system of anaerobic digestion showed stability conditions, with no noticeable scum or foaming problems. The anaerobic treatment of diluted municipal waste water is done using immobilized fixed bed anaerobic batch reactor. The source of waste generation is a mixed sludge collected from dock yard. The present study, thus initiated a need based experimental work on anaerobic digester incorporated with immobilized poly urethane foam system. The kinetic parameters are also estimated using experimental data. Empirical relations were developed for the characteristics like BOD, COD, SCOD, TDS and TSS using modeling equations.

Evaluation of Uncertainty of Chemical Oxygen Demand Measure in Drinking Water / 环境与健康杂志

Objective To estimate the marginal value of the chemical oxygen demand (COD) in drinking water by evaluation of uncertainty. Methods According to Evaluation and Expression of Uncertainty in Measurement (JJF1059-1999), analysis of measure uncertainty of the chemical oxygen demand determined by acidic potassium permanganate titrate prescribed in Sanitary Standards for Drinking Water (2001) was conducted. Results The type A relative standard uncertainty was 0.584%, type B was 0.781%, in which the sub-item uncertainty led by using 25 ml burette was 0.708%, the water sample volume was 0.056%, the adjusted potassium permanganate standard solution was 0.325%; the relative combined standard uncertainty was 0.975%, the expanded uncertainty was 1.95%. Conclusion According to the result of the uncertainty (3.08?0.06) mg/L, COD in the polluted sample exceeds the limit, the use of 25 ml burette produced the most contribution to the uncertainty.

Comparison of 3 Methods for Determination of Chemical Oxygen Demand of Water / 环境与健康杂志

ve To compare the advantage and disadvantages of spectrophotometry assay, microwave di-gestion and standard circumfluence method for determination of chemical oxygen demand (COD) in various water samples. Methods The levels of COD of the water samples were determined by spectro-photometry, microwave di-gestion and standard circumfluence method respectively. Results The relative standard variations were 4.3% ~ 9.59% for spectrophotometry, 3.58% ~5.61% for microwave digestion method and 4.03% ~ 4.27% for standard circumfluence method. The recovery rates of adding standard material were 90% -95% , 90% ~96% and 90% ~98% respectively. Conclusion The microwave digestion method showed easy, rapid and accurate. It presented good practical prospect in monitoring environmental samples.