Research On The Application Of Hydrolysis Fermentation On The Excess Sludge Reduction

The city sewage treatment plant is increasing with the acceleration of the process of thescale of city. Meanwhile the amount of excess sludge generated more and more. People are moreconcerned about methods of sewage to be innocuity, resourced andindustrialization. Excesssludge contains large amounts of carbohydrates, proteins and other organic matter. excess sludge,The sludge organic matter into volatile fatty acids (VFAs) by hydrolysis fermentation process,result in the sludge acid production, reduction of organic matter and decreasing of moisturecontent. Therefore, the purpose of this paper is to improve the sludge dewatering performanceand reduction organic matter. We studied the influence factors of hydrolysis fermentation processand the effect of surfactants dosing on the hydrolysis fermentation process and sludgedewatering performance.The influence factors of pH, temperature and sludge concentration on the hydrolysis andfermentation of the sludge was studied by static test. Action mechanism was investigated in theoptimum condition through the analysis of sludge particle size and the mensuration of extracellularpolymer substances.The results show that: when pH was10.0, property of producing acid andorganic matter reduction is the best. Acid production and the dewaterability is best at30℃. Therecycling of VFAs is highest in the sludge density60000mg/L. The recycling of VFAs ratereached at123.7mg/L with the volume reduction113.9%and organic matter decreased10.7%after5day fermentation in the optimum condition.Conditioning sludge by the three different types of surfactants, the effects of surfactants onthe hydrolysis and fermentation of the sludge was studied. The results show that the surfactant oftwelve sodium dodecyl benzene sulfonate (SDBS) can promote the hydrolysis of excess sludgefermentation and improve the dewatering performance of sludge, the optimum dosage of0.03g/g,the3day hydrolysis fermentation, recovery of VFAs was615.5mg/L, the3day of sludgedewatering performance best, filter cake moisture content is73.5%, volume reduction of95.7%,when the filter cake organic matter reduction of9.5%.