Abstract: The design of an external circulation reactor dealing with algae in Taihu lake was improved,and the performance of its quick start-up process and microbial properties of granular sludge were investigated. Cyanobacteria could be treated in around 35 d when running under the condition of dosing seed sludge,continuous operation with increasing load by steps,and intermittent agitation.When start-up finished,the removal rate of chemical oxygen demand(COD)by the reactor was about 85%,and gas production rate was about 380 ml·(g COD)^-1.In addition,the removal rate of microcystins reached 92%. Microorganisms in granular sludge were mainly cocci and filamentous bacteria,containing lots of Methanococcus,and plentiful holes in granular sludge provided the condition for transport of matter and degradation of microorganisms.The dominant methane-producing archaea in the granular sludge were Methanosphaera,Methanolinea,Thermogymnomonas,Methanoregula,Methanomethylovorans,Methanosaeta. Protease and coenzyme F₄₂₀ in the sludge particles showed higher activity.Intermittent stirring device and reflux system could overcome the drawbacks of floating and crusting of cyanobacteria in the reactor and at the same time accelerate mass transfer in the reactor so as to contribute to faster startup of the reactor.

Key words: anaerobic reactor, cyanobacteria, quick start-up, granular sludge;methane

摘要： 采用自行改进设计的外循环厌氧反应器处理太湖蓝藻,研究其快速启动过程中运行效能以及颗粒污泥微生物特性。实验结果表明:反应器采用“投加接种污泥、阶梯提高负荷连续运行、间歇搅拌”的启动运行方式,可以在35 d左右实现蓝藻成功处理。启动成功时,反应器对蓝藻化学需氧量(COD)去除率在85%左右,产气率在380 ml·(g COD)^-1左右,藻毒素的去除率达到92%;颗粒污泥中菌群以球菌、丝状菌为主,颗粒污泥内丰富的空穴为物质迁移和微生物降解提供通道。反应器启动成功后颗粒污泥中主要优势产甲烷古菌为Methanosphaera,Methanolinea,Thermogymnomonas,Methanoregula,Methanomethylovorans,Methanosaeta等;颗粒污泥中蛋白酶及辅酶F₄₂₀的活性较强。研究发现间歇搅拌装置及回流系统克服蓝藻在反应器中上浮结壳的弊端,同时加快反应器内传质效果,从而有助于反应器的快速启动。

关键词: 厌氧反应器, 蓝藻, 快速启动, 颗粒污泥, 甲烷