高效纤维质降解菌处理木薯酒精废液及其厌氧发酵动力学分析

为提高木薯酒精废液中固形物的降解效率，优化木薯酒精废液的厌氧发酵特性，采用高效纤维质降解菌群作为CSTR（continuous stirred tank reactor，连续搅拌反应器）接种污泥，通过逐级提高进料负荷，研究不同容积负荷下的厌氧消化性能及相应的酶活性变化，建立了厌氧发酵过程动力学模型.结果表明，在高温（55℃）条件下经长时间稳定运行，容积负荷为14 kg/（m3·d）（以COD_Cr计）时，反应器出水ρ（TCOD）（TCOD为总化学需氧量，以COD_Cr计）和ρ（SCOD）（SCOD为溶解性化学需氧量，以COD_Cr计）分别为15 367.6、10 982.8 mg/L，TCOD去除率达到70%~75%；φ（CH₄）在48%左右，沼气产率为0.22 L/g（以每g TCOD计）；此外，木聚糖酶活性、纤维素酶活性在该条件下达到最大值，分别为42.1、30.2 U.脱氢酶活性在容积负荷为12 kg/（m3·d）时达到最大值80.1 TFμg/（h·mL）.动力学模型研究表明，最大原料产气率（y_m）为0.335 L/g（以每g TCOD计），一级反应常数（k）为0.743 d-1，产气率为0.3 L/g，通过该模型可以得到最佳HRT（hydraulic retention time，水力停留时间）为11.5 d，最佳容积负荷为4.6 kg/（m3·d）.研究显示，在高温高容积负荷条件下，CSTR能够稳定的处理木薯酒精废液，并且能够获得较高的纤维素和半纤维素酶活性. 

Treatment of Cassava Alcohol Wastewater by Using Efficient Cellulose Degrading Microbial and the Anaerobic Fermentation Kinetics

In order to improve solid organics degradation rate of cassava alcohol wastewater and optimize its anaerobic fermentation characteristics, the high-efficiency cellulose degradation microbial was used as inoculum in the continuous stirred tank reactor (CSTR). The study investigates the anaerobic fermentation characteristics, enzyme activity changes as well as the kinetic model of anaerobic digestion by the increasing of volume loading rate. The results showed that the effluent concentration of ρ(TCOD)(total chemical demand) and ρ(SCOD)(soluble chemical demand) were 15, 367.6 and 10, 982.8 mg/L, respectively, and the total removal rate of ρ(TCOD) was 70%-75%, φ(CH₄) maintained at about 48%, the biogas generation rate was 0.22 L/g TCOD when the volume loading rate was 14 kg/(m3·d) (Calculated as COD_Cr) under the thermophilic condition (55 ℃). Besides, xylanase activity and cellulose enzyme activity reached its maximum value under this condition, which were 42.1, 30.2 U, respectively. In addition, dehydrogenase activity reached the maximum value of 80.1 μg/(h·mL) when the volume loading rate was 12 kg/(m3·d).The kinetic model results indicated that the maximum raw material biogas production rate y_m was 0.335 L/g TCOD and the first order reaction constant k was 0.743 d-1, according to the fitting curve, it could figure out the optimized hydraulic retention time (HRT) of 11.5 d and the volume loading rate of 4.6 kg/(m3·d) by the given anaerobic fermentation rate of y(t) 0.3 L/g TCOD. The anaerobic fermentation of cassava alcoholic wastewater by CSTR could be achieved stably at the high volume loading rate under the thermophilic conditions, and the activity of xylanase activity and cellulose enzyme was relatively high.