Study On Performance Of Sludge Reduction By Micro-Metazoa

Among all domestic and overseas,the sludge reduction technique with physics and chemistry which is invented has some flaws which consume large energy and priduce the second pollution.Using predation of micro-metazoa to reduce excess sludge production in wastewater treatment system is praised an eco-technology of sludge reduction with low-power and no-secondary pollution.But this technique has it's own disadvantage,that most pursuer don't put the micro-metazoa in the wastewater treatment system directly,but this will increase the difficult of the running and management,and they never consider the remove of the nourishment.Therefore,aiming at the problem,this paper chooses the tubifex which was gained easily as the micro-metazoa to reduce the sludge.And put the tubifex in the sewage reactor with the YJZH paddings directly to reduce sledge meanwhile treat with the sewage.This study is conducted from the effluence environmental factors on the tubifex, the effect of the sledge reduction and the nourishment remove by different tubifex grouops.The result indicates that:â‘ According the experiment of the acute toxicity,it educe that there is no effect on the survival of tubifex when the salinity is less than the 0.5%,the pH value is between 6-8.5,the NH₄⁺-N is less than 200mg/l,the COD value is less than 6000mg/l.And the untreated wastewater also never influences the survival of tubifex.â‘¡As the tubifex is hard to measure,so we use the tubifex like grown in group to measure.The tubifex group whose diameter is 1cm has 251 tubifex,the average weight of the bubifex is 0.001g.â‘¢The tubifex undergo four stages with adapting,increase,transition,stabilization in the whole experiment.The microorganism was never influenced by the tubifex.But it appears another kind of tubifex in the reactor which was never put the tubifex.â‘£As the tubifex are put in different number,the sludge yield is also different.And as the higher the number is,the less the sludge yield is.And the more the tubifex are put, the better the influence of the sledge reduction.And the VSS/SS value was also fall.⑤Tubifex never influence the remove of the COD.When the system reach the stabilization,the remove rate of the COD can measure up the first-class standard A of GB18918-2002.The number of the tubifex that is less the 167 per llitre don't influence the remove of N in the anaphase.But with the tubifex is more than 250 per llitre,the remove effect of TN is influence.â‘¥The tubifex never influence the P remove.Contrarily the more the tubifex are put,the better the influence of the P remove.The mostly reason may be that the tubifex eat a lot of dissolved P,and egest the undissolve P.Therefore,tubifex can reduce the sludge.And when the quantity of the tubifex group with 1cm dia is 10,the effect of the sludge reduction and the remove of the contamination aren't neither influence.The average suspended sludge yield is 0.1201 gVSS/gCOD,and the sludge reduction is 36.32%comparatively.