以聚乙烯醇为骨架材料的固相碳源反硝化脱氮试验研究

Denitrification of the solid carbon source with polyving akohol as framework material

针对反硝化过程中液态碳源投加量难以控制的问题,研发了一种缓释固相碳源。对比了不同骨架材料、乳化剂及组分配比对固相碳源脱氮性能的影响,优化固相碳源制备条件,并分析其释碳规律。结果表明,以聚乙烯醇(PVA)为骨架材料,失水山梨糖醇脂肪酸酯(SPAN80)为乳化剂,PVA∶淀粉质量比为1∶1时制得的固相碳源释碳效果和脱氮效果更优,对于硝态氮为25~30mg/L模拟污水,其硝态氮去除率可以达到95%以上,出水COD保持在80mg/L左右。在连续流试验中,系统可在3d内迅速实现稳定反硝化脱氮,高效脱氮时间可维持在40d左右,在实际工程应用中,可以通过调节水力停留时间、反应器流态等参数,提高固相碳源的使用寿命。

Aiming at the problem that liquid carbon source dosage was difficult to control during denitrification process,a slow-release solid carbon source was developed to solve it. The effects of different framework material,emulsifier and addition proportion on denitrification efficiency of solid carbon source were compared,the preparation conditions of solid carbon source were optimized,and the carbon release characteristic of obtained solid carbon sources was analyzed. The result showed that the solid carbon source,with polyving akohol (PVA) as framework material,sorbitol fatty acid ester (SPAN80) as additive and PVA∶starch mass ratio of 1∶1,had a stronger COD release capacity and a better denitrification efficiency,when the nitrate nitrogen was 25-30 mg/L ,the nitrate nitrogen removal efficiency could be stably more than 95% and the effluent COD was kept at about 80 mg/L . In the continuous flow experiment,the obtained solid carbon source also presented perfect denitrification performance,the system could quickly achieve denitrification in 3 days,and high denitrification stage could maintain about 40 d. In practical engineering application,the service life of solid carbon source could be improved by adjusting operation parameters such as hydraulic retention time,reactor flow state and so on.