连续全混反应处理木薯酒精废水产沼气能力研究

Study on Biogas Production Capacity of Treating the Cassava Alcohol Wastewater by Continuous Stirred Tank Reactor(CSTR)

燃料乙醇是国家能源安全的重要一环,现在主要通过木薯等非粮作物发酵制得,发酵过程中会产生大量废水,废水处理问题成为制约技术革新的关键。高温厌氧条件下,利用连续全混反应（CSTR）对木薯酒精废水进行厌氧处理,探究容积负荷、温度和p H对反应器产甲烷能力的影响。通过试验发现：设备启动完成后,保证COD去除率在90%以上条件下能够达到的最大容积负荷为8.2 kg COD/（m^3·d）,容积负荷达到6.8 kg COD/（m^3·d）时,系统产甲烷能力达到最大值。58℃条件下,系统转化甲烷的效率最高。反应系统本身具有较强的p H调节能力,能够维持系统p H稳定在7.3～7.5之间;人为降低p H能够提高系统产气比,但气体中甲烷含量降低。

Fuel ethanol is an important part of national energy security.At present,it is mainly produced by the fermentation of non-grain crops such as cassava.A large amount of waste water is produced during fermentation,and the treatment of waste water is the key to the technological innovation.Under high temperature anaerobic conditions,Continuous Stirred-Tank Reactor（CSTR） was used for anaerobic treatment of cassava alcohol wastewater to explore the effects of volume loading,temperature and p H on the methane-production capacity of the reactor.Through the experiment we found that when the equipment started up,the maximum volume loading was8.2 kg COD/（m3·d） in the condition of the COD removal rate over 90%.The system reached the maximum capacity of methane production when volume load was 6.8 kg/（m3·d）.Under the temperature of 58℃,the efficiency of methane conversion in the system was the highest.There was a strong ability of the reaction system to adjust p H of which could maintain the p H stability of the system in the range of 7.3～7.5;Artificially reducing p H could increase the biogas production rate,but the methane content in the gas decreased.