Article

Slaughterhouse Wastewater Treatment by Combined Chemical Coagulation and Electrocoagulation Process

Queen's University Belfast, United Kingdom
PLoS ONE (Impact Factor: 3.23). 06/2012; 7(6):e40108. DOI: 10.1371/journal.pone.0040108
Source: PubMed

ABSTRACT

Slaughterhouse wastewater contains various and high amounts of organic matter (e.g., proteins, blood, fat and lard). In order to produce an effluent suitable for stream discharge, chemical coagulation and electrocoagulation techniques have been particularly explored at the laboratory pilot scale for organic compounds removal from slaughterhouse effluent. The purpose of this work was to investigate the feasibility of treating cattle-slaughterhouse wastewater by combined chemical coagulation and electrocoagulation process to achieve the required standards. The influence of the operating variables such as coagulant dose, electrical potential and reaction time on the removal efficiencies of major pollutants was determined. The rate of removal of pollutants linearly increased with increasing doses of PACl and applied voltage. COD and BOD(5) removal of more than 99% was obtained by adding 100 mg/L PACl and applied voltage 40 V. The experiments demonstrated the effectiveness of chemical and electrochemical techniques for the treatment of slaughterhouse wastewaters. Consequently, combined processes are inferred to be superior to electrocoagulation alone for the removal of both organic and inorganic compounds from cattle-slaughterhouse wastewater.

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    • "sses at laboratory scale for syn - thetic SWW treatment . Results showed that combined processes are more efficient than individual processes for SWW treatment . Up to 95% TOC , 98% COD , and 97% BOD removals were obtained for influent concentrations of 973 mg / L at HRTs in the ABR of up to 3 . 8 days and 3 . 6 h within the UV / H 2 O 2 reactor . Bazrafshan et al . ( 2012 ) assessed the performance of combined chemical coagulation ( CC ) and EC for the SWW treatment . BOD and COD removal rates were directly proportional to the applied voltage and coagulant dosage with up to 99% removal efficiencies for both parameters . As a result , the combined CCeEC processes were found to be more efficient than EC al"
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    • "As it mentioned earlier, low BOD 5 /COD ratio indicates the necessity of an efficient physicochemical treatment for this wastewater. Similar findings were reported by Bazrafshan et al. on slaughterhouse wastewater treatment by combined chemical coagulation and electrocoagulation [47] "
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