Electrocoagulation of cheese whey wastewater

Cheesewheywastewater is a by-product of thedairyindustry. Cheesewhey is yellow?gren liquidwhichremainedaftertheprecipitationandremoval of milkcaseinduringcheesemaking.Majorcomponentsarelactose (44?52 g/L), proteins (6?8 g/L) and mineral salts (4?9 g/L) .Wheywastewater is producedmorethan 145×106 tonnesperyear in theworld-wideandmorethanhalfof whey produced is disposed of in the environment.It is a protein andlactoserichby-product of thecheeseindustryanditscost-effectiveutilizationordisposal has becomeincreasinglyimportantduetomorestringentlegislativerequirementsforeffluentquality.Althoughseveralpossibilitiesforcheesewheyexploitationhavebeenexaminedoverthelast 50 years, approximatelyhalf of worldcheesewheyproduction is not treated, but is discharged as effluent.Inthisstudy,cheesewheywastewaterwastreatedwithelectrocoagulation. Twouniqueelectrocoagulationreactorsweredesignedtotreatcheesewheywastewater. Wheywastreatedwithtwodifferenttypes of ironreactors .Reactorsperformancewereestimated in bothbatch EC reactorandcontinuous EC reactor.The effect of current density ,pH, supporting electrolyte type, supporting electrolyte concentration,concentrationof H2O2, addition type of H2O2, polyelectrolyteand time were investigatedforbatch EC reactor. Current density ,pH, flow rate andeffect of H2O2wereexaminedbydesigning of an experimentthe COD removalefficiencyforcontinuous EC reactor.CODvalue of 15 500 mg/Lcheesewheywastewaterwastreatedwithelectrocoagulation .It is decreased 1408 mg/L COD withbatch EC reactor ; 1760 mg/L COD withcontinuous EC reactor. Respectively, COD removalefficienciesare %90,92 and %88,65.Keywords: COD removal, Electrocoagulation, Iron electrodes