a b s t r a c t
Access tocleanwaterhasbeenagreatchallengearoundtheglobeduetothehighpollutantcontentsin
the water.Therefore,thereisahighdemandoffreshwaterresourcesoradireneedofcleanrecycle
wastewaterasanewsourceofwatersupply.Inordertoaccomplishthis,newconceptorengineering
systemsneedtobedevelopedwherehybridwastewatertreatmentsystemcanbeaneffectivepollutants
removal.Wastewatercontainsenergyintheformofbiodegradableorganicmatter.Theconceptof
accomplishing wastewatertreatmentandgenerateenergysimultaneouslyhasbeenatrendrecentlyand
can bedonewithhybridwastewatertreatmentsystem.Energygainedfromsuchhybridsystemis
thereforebothsustainableandenvironmentalfriendlywhichmaybegoodsourceofbio-energyto
compliment thepowerofatreatmentplant.Inthispaper,weclassifyhybridwastewatersystems
typically includephysical–biological hybrid,physical–chemical hybrid,chemical–biological hybridand
physical–chemical–biological hybridsystem.Fromthedetailedliteraturegatheredthusfar,hybridsys-
tems demonstratedsomepotentialadvantagescomparedtostand-alonesystemssuchas:morestable
and sustainableinthevoltagegenerated,betteroveralltreatmentefficiency andenergysavings.