活性污泥热碱水解释碳的实验研究

Experimental study of carbon release from activated sludge by alkaline thermal hydrolysis

实验采用热碱条件(T为60℃,pH为11),分别对自养型、异养型和富集进水碳源后的活性污泥(富碳污泥)进行了水解释碳研究。结果表明,自养型、异养型和富碳污泥的水解释碳过程都能在运行24 h后趋于稳定,释碳量分别为811、933和781 mg SCOD/g VSS,且对碱的消耗分别为130.2、122.1和151.1 mg NaOH/mg SCOD。同时,研究结果表明,水解后污泥的沉降性能很差,在量筒内长时间的沉淀也不会出现明显的泥、水分界线,通过观察水解污泥的微观结构发现,污泥在水解后,其絮体结构完全被破坏,污泥松散,呈糊状;但是通过短时间(≤0.5 h)的沉降,水解污泥能够形成一个比较明显的污泥浓度分界线,约60%以上的污泥量能够沉降到量筒总高度的1/3以下部分。

Carbon releases of autotrophic sludge,heterotrophic sludge and the sludge enriched with influent carbon（enriched sludge） by hot alkaline hydrolysis of temperature 60 ℃and pH 11were investigated.Results indicated that the carbon releases of autotrophic,heterotrophic and enriched sludge could reach the maximum after 24 hours hydrolysis and was stable at 811,933 and 781 mg SCOD/g VSS,respectively,companying alkali consumption of 130.2,122.1 and 151.1 mg NaOH/mg SCOD,respectively.Moreover,it was found that the hydrolyzed sludge had bad settleability and could not form a clear boundary of sludge and water after long time settling of above 5 hours.By microscopic observation of the hydrolyzed sludge,it was found that the sludge floccule was destroyed seriously,and sludge structure became incompact and mushy.However,an obvious boundary of the sludge with different concentrations was found after a short settling time of below 0.5 hour,and more than 60% of the total sludge biomass could settle down to the bottom.