典型BNR工艺污泥中温和高温厌氧消化特征对比

Comparison of Mesophilic and Thermophilic Anaerobic Digestion Characteristics of Sludge from Typical BNR Process

针对我国城市污水处理厂生物营养物去除(BNR)工艺目前产生的大量污泥,以典型BNR工艺氧化沟和A/A/O工艺产生的污泥为研究对象,考察中温[(36±1)℃]和高温[(52±1)℃]厌氧消化时BNR工艺污泥的水解、产气及减量特征。结果表明,在中温和高温厌氧消化条件下,氧化沟工艺污泥的最大比产甲烷速率(R_(max))和最大产甲烷潜力(P_(0))均明显低于A/A/O工艺污泥,且其消化时间更长。此外,高温厌氧消化大幅提高了BNR工艺污泥的R_(max)和P_(0),并缩短了消化时长,如高温下氧化沟工艺污泥的R_(max)、P_(0)和消化时长分别为中温下的2.47倍、1.33倍和53.8%。高温厌氧消化可明显提高BNR工艺污泥的有机物降解率,可满足《城镇污水处理厂污泥处理处置污染防治最佳可行技术指南(试行)》(HJ—BAT—002)对污泥中有机物降解率的要求。

Focusing on a large amount of sludge produced in the biological nutrient removal(BNR)processes of municipal wastewater treatment plants in China,this paper investigated the characteristics of hydrolysis,gas production and reduction of sludge from two typical BNR processes(oxidation ditch and A/A/O process)during mesophilic[(36±1)℃]anaerobic digestion(MAD)and thermophilic[(52±1)℃]anaerobic digestion(TAD).Under MAD and TAD conditions,both the maximum specific methane production rate(R_(max))and the maximum methane production potential(P_(0))of sludge from oxidation ditch were significantly lower than those of sludge from A/A/O process,and the digestion time was longer.In addition,TAD significantly increased the R_(max)and P_(0)of sludge from BNR process and shortened the digestion time.For example,the R_(max),P_(0)and digestion time of sludge from oxidation ditch in TAD were 2.47 times,1.33 times and 53.8%of that in MAD,respectively.TAD significantly improved the organic degradation rate of sludge from BNR process,which met the requirements of sludge organic degradation rate specified in Guideline on Best Available Technologies of Pollution Prevention and Control for Treatment and Disposal of Sludge from Municipal Wastewater Treatment Plant(on Trial)(HJBAT-002).