3.4.1.Overviewofsludgegeneratedfrom flotation
Table2 demonstratesthatthesludgegeneratedfromthetreatedeffluents canberecycledasuseful
productssuchasananimalfeed,afertilizerandabiofuel.Itshowssomecomparativedataofprotein
(nitrogen),phosphorusandenergylevelfromdifferenttypesofanimalfeeds,foodwastes,biofuels
and pigmanurewiththoseofthesludgegeneratedfrom flotation.Foodwastescollectedbylivestock
farmers areusuallyutilizedasanimalfeedscontaininghighwatercontent.
3.4.2. Watercontentandamountgeneratedofthesludge
Table2 revealsthatthewatercontentofallthesludgesamplescollectedwaslessthan70%forthe
study period(15May–22 May2009).Thehighestwatercontentwas63.7%whilethedriestonewas
45.6% anditgaveameanvalueof54.7%.Itsvaluewasnearlythesameasthoseoffoodwastesexcept
breadwaste[32:10.7%]andtomatowaste[33:81.4%].Thefoodwasteswerecollectedandusedas
feeds ormixedwithotheringredientsforlivestockrearing.Therefore,thesludgegeneratedfrom
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