两种共混BDPs 作为生物膜载体和碳源的脱氮研究比较

采用 PHBV/PLA 和PHBV/木纤维素两种可生物降解聚合物作为反硝化碳源和生物膜载体进行序批试验和填充床连续反硝化试验。序批试验结果表明, PHBV/木纤维素固相碳源启动速度快于PHBV/PLA, 但两者24 小时脱氮效果并无明显差异; 反硝化速率分别为0.10 mg N/(L·h·g)和0.12 mg N/(L·h·g)。填充床连续反硝化试验结果表明, 两种碳源NO3 ?-N 去除负荷分别为13.95 mg/(L·h)和14.02 mg/(L·h), 去除率均高于90%, PHBV/PLA 比PHBV/木纤维素具有更好的碳源控释能力。扫描电镜结果表明, 内部结构特征的差异是共混固相碳源脱氮性能和碳源控释性能产生差异的关键因素。

Comparison of Two Biodegradable Polymer Blends as Biofilm Carrier and Carbon Source for Nitrogen Removal

Two kinds of biodegradable polymers (BDPs), PHBV/PLA and PHBV/Methyl Cellulose blends, were used as biofilm carrier and carbon source in batch and continuous packed-bed reactors for nitrogen removal. Results of batch test indicated that denitrification with PHBV/Methyl Cellulose blends had a shorter start-up period in comparison to that with PHBV/PLA, but there was no significant difference on the nitrogen removal efficiency after 24 hours and denitrification rates were found to be 0.10 and 0.12 mg N/(L·h·g) respectively. The NO3 ?-N removal loads of 13.95 and 14.02 mg/(L·h) for PHBV/PLA and PHBV/Methyl Cellulose blends were achieved in the continuous packed-bed reactor while their removal efficiencies exceeded 90%。Further DOC analysis showed that PHBV/PLA had a better profile of controlled carbon release for desired denitrification. Scanning Electron Microscope (SEM) images suggested that difference between internal structures of both blends affected nitrogen removal and controlled carbon release.