嗜酸光合细菌耦合萎缩芽孢杆菌降解马铃薯加工淀粉废水条件优化

Optimization of experimental conditions for the treatment of potato starch wastewater by coupling of acidophilic photosynthetic bacteria and Bacillus atrophaeus

【目的】研究嗜酸光合细菌耦合萎缩芽孢杆菌在实验室条件下降解马铃薯淀粉废水污染物。【方法】以马铃薯加工淀粉废水为材料,实验室条件下研究2种菌株复配比例、复合菌接种量、复合菌协同培养方式等对淀粉废水COD和恶臭气体的降解效率。【结果】嗜酸光合细菌∶萎缩芽孢杆菌活菌数比=10∶1,接种量15%,30℃,采用分段连续培养前72 h厌氧光照(5000 lux)培养,之后72 h采取厌氧光照∶黑暗好氧=12 h∶12 h方式。在最优条件下添加1 g/L乙酸钠能够使淀粉废水COD降解率由对照组的16.9%提升到98.21%,水体中氨氮,硝氮,总磷,硫醇,硫化氢等污染物降解效率均超过98%以上,同时较高的pH使水体实现自絮凝,沉降速度达到8 cm/h。【结论】嗜酸性光合细菌和萎缩芽孢杆菌最适生长pH差异造成的生态位分化是其耦合以及高效降解淀粉废水污染物的主要原因。

【Objective】This project aims to optimize the experimental conditions for the treatment of potato starch wastewater by coupling of Acidophilic photosynthetic bacteria(PSB)and Bacillus atrophaeus(BA).【Methods】Potato starch wastewater was used as study materials and they were divided into treatment and control groups.The treatment groups were the compounding ratio,inoculation,culture methods of the two strains and the wastewater contaminants degradation(like COD and Malodorous gas)rates were used to reflect their effects.Finally,we tested the total application effect of the optimized experimental conditions for the treatment of potato starch wastewater.【Results】The optimized experimental conditions for the treatment of potato starch wastewater were∶the ratio of PSB to BA=10∶1,15%of inoculation,30℃of incubation,and incubated 144 h including light intensity 5,000 lx under anaerobic illumination for the first 72 h,then the next 72 h incubated under anaerobic illumination/aerobic=12 h∶12 h.The COD degradation rate under the optimized condition was increased from 16.9%in control group(without inoculation)to 98.21%,and it also showed more than 98%of degradation rate of other contaminates(like ammonia nitrogen,nitrate nitrogen,total phosphorus,mercaptan,hydrogen sulfide)and its self-flocculating rate was 8 cm/h.【Conclusion】The results suggested that the wastewater contaminated with high degradation rate by coupling of acidophilic photosynthetic bacteria and Bacillus atrophaeus is mainly attributed to the niche differentiation of the optimal growth pH.