果汁废液作为碳源强化生物脱氮效果的研究

Study on the effect of juice waste liquid as a carbon source to enhance biological nitrogen removal

针对污水处理厂生物脱氮碳源缺乏、需外加大量商品碳源、投加成本过高的问题,研究采用果汁废液作为补充碳源,考察其强化生物脱氮的效果,并进行工程应用。结果表明,果汁废液有机物含量高、可生化性好、氮磷含量低,其作为补充碳源投加5%(体积分数)时,第一阶段反硝化速率是污水厂原水的5.79倍。通过水解酸化预处理可进一步提高果汁废液中易降解有机物含量,平均提高57%。工程投加24 t/d的果汁废液,较仅投加乙酸钠系统出水TN可降低2~3 mg/L,减少乙酸钠投加量0.6~0.9 t/d,年节约成本24~36万元。

In view of the lack of carbon source for biological denitrification in sewage treatment plants,the juice waste liquid was employed as a supplementary carbon source to solve the need and high cost of large amount of commercial carbon source. The performance of the juice waste liquid on enhancing biological denitrification was investigated and applied in engineering. The results showed that the juice waste liquid had high organic content,good biodegradability and low nitrogen and phosphorus contents. When it was added as a supplementary carbon source by 5%(volume fraction),the first stage denitrification rate was 5.79 times that of the sewage plant raw water. The content of easily degradable organic matter was further increased by hydrolysis acidification pretreatment,with an average increase of 57%.When 24 t/d of juice waste liquid is added into the system,the effluent TN concentration can be reduced by 2-3 mg/L compared with that of the system only adding sodium acetate,the dosage of sodium acetate can be reduced by 0.6-0.9 t/d,and the annual cost savings will be 240-360 thousand yuan.