混凝-A^3-MBR处理餐厨垃圾发酵废液运行条件优化与特性

Optimization operating conditions and characteristic of treatment for kitchen waste fermentation wastewater by coalugation-A^3-MBR process

采用混凝-两级厌氧/缺氧/好氧-膜生物反应器(A3-MBR)处理实际餐厨垃圾发酵废液,通过对运行参数进行优化确定最优工况,并考察其在该条件下长期运行的处理效果。结果表明,混凝预处理的最适pH为8,最佳混凝剂投加量为1 000 mg·L^(-1)。A3-MBR系统在最优运行条件:总HRT为110 h,回流比为200%,进水COD负荷控制在2.3~3.6 g·(L·d)-1下可稳定运行。当系统进水COD、TN、NH3-N和TP浓度分别为(10 984±383)、(335.9±16.2)、(209.1±6.7)和(37.2±2.3)mg·L^(-1)时,系统进水有机负荷为2.3~3.5 g·(L·d)-1,在最优条件下处理系统出水的COD、TN、NH3-N和TP分别为(202±23)、(62.1±7.1)、(0.33±0.13)和(8.3±0.9)mg·L^(-1),其去除率分别为98.2%、81.5%、99.8%和77.8%。A3-MBR系统对有机物具有良好的去除效果,厌氧段未积累挥发性脂肪酸。最终出水中溶解性有机物主要为II区芳香族蛋白质类似物,残留的挥发性有机物以酯类物质为主。

A combined coagulation and two-phase anaerobic / anoxic / oxic-membrane bioreactor（ A^3-MBR）process was developed at the lab scale to treat kitchen waste fermentation wastewater. The operational parameters were optimized,and the performance of the process under such conditions was investigated. The results showed that the optimum pH and coagulant dosing for coagulation were 8 and 1 000 mg·L^-1,respectively. In addition,the best performance occurred with an HRT of 110 hours,a reflux ratio of 200%,and an influent COD loading from 2. 3 to 3. 6 g ·（ L · d）- 1. Under these operational conditions; with influent concentrations for COD of（ 10 984 ± 383） mg·L^（-1）,TN of（ 335. 9 ± 16. 2） mg·L^（-1）,NH_3-N of（ 209. 1 ± 6. 7） mg · L^（-1）,and TP of（ 37. 2 ± 2. 3） mg·L^（-1）; and influent organic loading from 2. 3 to 3. 5 g·（ L·d）- 1,the effluent COD,TN,NH_3-N,and TP concentrations were（ 202 ± 23）,（ 62. 1 ± 7. 1）,（ 0. 33 ± 0. 13）,and（ 8. 3 ± 0. 9） mg·L^（-1）,respectively,corresponding to removal rates of 98. 2%,81. 5%,99. 8%,and 77. 8%. The A3-MBR effectively removed the organic compounds without accumulation of volatile fatty acids during the anaerobic period. Region II of the aromatic proteins and esters took the main part of the dissolved organic matter and volatile organic compounds in the effluent,respectively.