AnMBR/A/OMBR处理焦化废水的运行条件优化与运行效果

Operating conditions optimization and characteristics study of an AnMBR/A/OMBR Process for coking wastewater treatment

采用厌氧膜生物反应器/缺氧/好氧膜生物反应器(An MBR/A/OMBR)处理某焦化厂实际焦化废水,通过优化运行参数使该工艺达到最佳运行工况,并考察最佳运行条件下系统长期稳定运行的处理效果。结果表明,向进水添加磷源能满足微生物的生长需求并促进脱氮过程,同时控制OMBR内的pH能较好地保证系统出水NH_3-N的去除率和稳定性。AnMBR/A/OMBR系统的最佳运行条件为:总HRT为61.3 h,进水TP浓度为(2.3±0.3)mg·L^(-1),OMBR内pH为(7.5±0.2)、DO为4~6 mg·L^(-1),回流比为2∶1。当系统进水COD、TOC、NH_3-N和TN的平均浓度分别为(1790±17)mg·L^(-1)、(447.3±9.1)mg·L^(-1)、(107.3±5.2)mg·L^(-1)和(221.9±5.6)mg·L^(-1)时,在最优条件下系统出水的平均浓度分别为(254±76)mg·L^(-1)、(53.8±3.2)mg·L^(-1)、(3.9±1.1)mg·L^(-1)和(70.0±8.8)mg·L^(-1),去除率分别为(85.7±0.9)%、(88.0±0.7)%、(96.4±1.1)%和(68.5±3.7)%。进水中Ⅰ、Ⅱ区芳香族蛋白质类似物和Ⅳ区溶解性微生物副产物的总和所占比例达88.5%,系统出水中Ⅱ区芳香族蛋白质类似物占40%,含量最高。

A laboratory scale anaerobic membrane bioreactor/anoxic/aerobic membrane bioreactor （AnMBR/A/ OMBR） was developed and the operating conditions optimized for treatment of coking wastewater. Its perform- ance under optimum operating conditions was investigated. The results indicated that the addition of a phosphorus source in the influent could meet the growth need of microorganisms and promote the denitrification process. The control of pH in the OMBR ensured steady ammonia-nitrogen removal in the AnMBR/A/OMBR system. The best performance was obtained at total HRT 61.3 h,influent TP （2.3 ±0. 3）mg · L^-1 ,pH （7.5 ±0.2） ,and DO 4- 6 mg· L^-1 of OMBR,with reflux ratio 2： 1. Under these operating conditions,and with the influent conditions of COD （（1 790±17）mg· L^-1）,TOc （（447.3±＋9.1）mg· L^-1）,NH3-N （（107.3±5.2）mg· L^-1）,and TN （ （221.9 ±5.6） mg· L^-1） ;the effluent COD,TOC,NH3-N,and TN were （254 ± 76） mg · L^-1 , （53.8 ± 3.2） mg· L^-1,（3.9 ±1.1）mg · L^-1 ,and （70.0 ±8.8）mg · L^-1 The removal rates were （85.7 ±0.9）% ,（88.0 ± 0.7） % , （96.4 ± 1. 1 ） % , and （68.5 ± 3.7 ） % , respectively. The total proportion of Region Ⅰ and Ⅱ aro- matic protein analogues, and Region Ⅳ soluble microbial by-products in the influent,was 88.5% . The content of Region Ⅱ aromatic protein analogues was highest in the AnMBR/A/OMBR system effluent, and accounted for 40%.