Study On The Effects Of Rare Earth Ce On Granulation Of Activited Sludge And The Performance

There are abundant rare earth in our country,the field where rare earth can apply to becomes wider along with the technique develops.Rare earth have biological effect on animal,plant and bacteria.Rare earth can enhance the activity of enzyme,increase the amount of microorganism.The major content of this article comprise three parts: The first is effect of rare earth(Ce)on activated sludge,the second is effect of rare earth on formation of aerobic granular sludge,the last is study on treatment of beer wastewater by aerobic granular sludge.The purpose of this article is the prospect of rare earth applying to environment problem and the prospect of aerobic granular sludge treating on treating high strength organic wastewater.The main researches included as follows:1.The effect of rare earth(Ce)on growth kinetic of activated sludge,EPS in activated sludge,and microbial morphology were researched.Result indicated right strength of rare earth(Ce)can improve growth,enhance the activity of enzyme, improve surface of activated sludge,stimulate life of microorganism.But high strength rare earth(Ce)were inhibitory and toxicity.It caused enzyme destroyed, depressed the activity of enzyme,wrecked structure of zoogloea,and it is bad to sludge depositing.2.Effect of rare earth(Ce)on formation of aerobic granular sludge in two same SBR was studied while Ce³⁺was added to one SBR,the nutriment was synthetic wastewater,the process was divided to three periods according air flow rate and volume loading.Result indicated that aerobic granular sludge which Ce³⁺was added formed more early than aerobic granular sludge which was cultivated commonly.In first period the effect of rare earth(Ce)is most conspicuous.The shape of sludge,the amount of EPS,amend the ratio of Protein/Amylose,hydrophobicity of sludge, became more different between the two SBR in first period,right strength of rare earth(Ce)have effects on degradation,improve phosphorus removal ability. Phosphate uptake and release experiment indicated denitrifying phosphate accumulating bacteria was main phosphate accumulating-bacteria in aerobic granular sludge,right strength of Ce³⁺improve the growth of denitrifying phosphate accumulating bacteria.Ce³⁺have effect mainly at early period,the effect was weakening along with granulation and time.aerobic granular sludge cultivated adding Ce³⁺was solider than cultivated commonly,the kinds of microorganism is more,the volume of microorganism is smaller,the distance of interstice is shorter.3.Effect of treatment of beer wastewater by aerobic granular sludge was good, the effluent water can meet table 1 of Discharge Standard of Pollutants for beer industry(GB19821-2005).the characteristic of operation cycle showed that microorganism is hunger in residual time in one operation cycle,and it helped aerobic granular sludge more compact.The dynamic of improved aerobic granular is studied, while treating beer wastewater.The degradation dynamic parameter is below:V_maxof the aerobic granular is 0.64 h^-1,Ks of the aerobic granular is 136.6 mg/l and 336 mg/l. The growth dynamic parameter is below:Y of the aerobic granular is 0.142 kgMLVSS/kgCOD,K_d of the aerobic granular is 0.035 d^-1.