海藻酸钠包埋固定化微生物处理含油废水研究

采用海藻酸钠固定化包埋活性炭与菌Brevibacillus parabrevis Bbai-1,制备海藻酸钠-活性炭固定化微球。通过活性炭吸附前后的菌浓变化,测定了25℃时活性炭对Bbai-1的最大吸附量。采用正交试验优化了影响海藻酸钠-活性炭固定化微球的物理性质和微生物活性的4个主要因素(海藻酸钠浓度,活性炭含量,种子菌液浓度和交联时间),确定了固定化微球的最佳制备条件:海藻酸钠浓度为3.5%,活性炭含量为0.7%,种子菌液浓度为6×107 cell/mL,交联时间为24 h。并在25℃,原油含量为0.2%,固定化微球与含油培养基的体积比为3:20时,以游离菌作对比,考察了固定化微球降解原油的最佳pH和盐度。结果表明,固定化菌在pH 6~9,盐度为1.5%~3.5%时,原油降解率可达50%以上,比游离菌提高了20%,且具有较高的盐度适应能力和较宽的pH适应范围。

Application of Alginate Embedded Immobilized Microbes in Oil Wastewater Treatment

Alginate-activated carbon immobilized microspheres(AACIM)were prepared through immobilized biosorption of activated carbon and Brevibacillus parabrevis Bbai-1 by sodium alginate.The maximum adsorbing capacity of Bbai-1 on activated carbon was measured at 25 ℃ by comparing the biomass of Bbai-1 before and after adsorption.4 major factors such as alginate concentration,activated carbon content,seed bacteria biomass and cross-linking time on physical properties and microbial activity of AACIM were investigated by orthogonal test,and the optimal preparation conditions of AACIM were determined as 3.5% of alginate,0.7% of activated carbon,6×107 cell/mL of seed bacteria and 24 h of cross-linking time.At the temperature of 25 ℃ and oil content 0.2%,the optimal volume ratio of AACIM and oil medium 3:20,the optimal pH and salinity of crude oil degradation for immobilized bacteria were investigated to compare with the free ones.Results indicated that under the conditions of pH 6~9 and salinity 1.5%~3.5%,the biodegradation rate of immobilized bacteria reached above 50%,which was 20% more than that of free ones,and the immobilized bacteria were also able to endure higher salinity and adapt to wider range of pH.