两相厌氧消化工艺处理鸡粪

Treatment of chicken manure by two-phase anaerobic digestion reactor

以鸡粪为发酵原料,采用序批式两相厌氧消化工艺在中温条件(37℃)下对其进行消化处理。分别将水解酸化相和产甲烷相pH值控制在5.5±0.3和7.0±0.3,通过改变进样含固率(TS)研究有机负荷(OLR)对两相消化系统处理鸡粪过程中污染物转化和去除效果的影响。结果表明,水解酸化相出水总有机碳(TOC)、挥发酸(VFAs)和氨氮(NH4+-N)浓度都随OLR升高而升高。VFAs组成相对稳定,其中乙酸占总VFAs浓度的57%～64%,其次为正丁酸和丙酸。产甲烷相出水TOC和VFAs稳定在较低水平,TOC去除率最大达到90%以上。产甲烷相进水氨氮主要以NH4+形式在反应器内不断积累。实验后期产甲烷相生物气中甲烷体积分数维持在64%上,证明两相消化系统在实验条件下良好运行。

Two-phase batch anaerobic digestion process was carried out under the mesophilic condition （37℃） for the treatment of chicken manure. The pH values of hydrolysis acidification phase and methanogenesis phase were controlled at 5.5 ± 0.3 and 7.0 ± 0.3, respectively. The effects of organic loading rate （OLR） on the conversion and removal of pollutant were studied by changing the influent total solid content. The results indicate that with OLR increase, the concentration of total organic carbon （TOC）, volatile fatty acid （VFA） and ammonia-nitrogen （NH4＋ -N） in the effluent of hydrolysis acidification phase significantly increase. The distribu- tion of individual VFA is stable with acetic acid accounting for 57% -64% of total VFAs concentration, followed by n-butyric acid and propionic acid. The TOC and VFAs concentration in the effluent of methanogenesis phase is in a low level; and the maximum removal rate of TOC is more than 90%. In the late stage of experiment, the methane content produced in methanogenesis phase is above 64% by volume, suggesting that two-phase anaero- bic digestion process was ooerated well under the experimental condition.