为了解决厌氧氨氧化颗粒污泥容易破坏并发生上浮,造成系统出水不稳定甚至崩溃的问题,主要针对厌氧氨氧化颗粒污泥上浮机理及控制策略进行综述.研究结果发现:厌氧氨氧化颗粒污泥上浮的主要机理是当氮负荷率(nitrogen loading rates,NLRs)过高时,厌氧氨氧化颗粒污泥产生大量氮气(N2)无法释放,在颗粒污泥内部形成气囊或附着于颗粒污泥表面,致使颗粒污泥密度降低,导致上浮.相应控制策略包括:控制颗粒污泥粒径(1.5~4.0mm);适当控制NLRs(以N计,下同)(4.0~34.5 kg/(m^3·d));适当提高进水磷和钙的质量浓度(籽(KH2PO4)=10mg/L,籽(Ca Cl2·2H2O)=0.15~5.65 mg/L);选择带有搅拌功能的反应器;调整排水口位置并控制排水时间等.
To solve the problem of breaking and floating of anaerobic ammonium oxidation(anammox)granular during reaction may lead to instability or collapse of the treatment system,the mechanism and control strategy of anammox granular sludge floating were summarized in this paper.The previous studies showed that the density of the anammox granule decreased which was thought to be the main mechanism of granular sludge floating.Therefore,at high nitrogen loading rates(NLRs) level,floating would occur which might be the fact that the anammox granular sludge produced a large amount of nitrogen gas(N_2)and the gas could not release easily.Then the gas trapped in the granular sludge inside or attached to the granular sludge surface.There were some strategies which were adopted to control the anammox sludge floating,such as controlling the particle size of the sludge(1.5 ~4.0 mm);controlling the NLRs(4.0~ 34.5 kg/(m·d));improving the concentrations of phosphorus and calcium in the influent(p(KH2PO4) = 10 mg/L,p(CaCl2-2H2O) =0.15 ~5.65 mg/L);using the reactor with stirring;adjusting the location of outlet and controlling the time of output,etc.