Biodegradable polymer supported denitrification (BPD) system shows good denitrification performance for the wastewater with low nitrate concentrations. In this study, a BPD system using Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) polymer as carbon source was developed to treat the wastewater with high nitrate concentrations. The denitrification performance, utilization ratio of PHBV polymers, and microbial community structure evolution and key denitrifying bacteria were comprehensively studied. Results indicated that an average nitrate removal efficiency of 99% could be achieved with an influent NO₃⁻-N concentration of 100 mg L⁻¹ and a hydraulic retention time (HRT) of 7.25 h. Mass balance model predicted that 80% of the PHBV polymers were consumed by denitrifying bacteria, close to 72% consumption in real condition, suggesting the model might be useful for PHBV polymers management in BPD system. Further, the bacterial community structures varied along the bioreactor profile, which closely linked to the concentration profiles of nitrate and ammonia. Metatranscriptomic analysis identified the key denitrifying bacteria as Comamonas, Acidovorax and Dechloromonas. The PHBV supported denitrification system developed in this study shows potential for removal of high concentration of nitrate from wastewater.

可生物降解的聚合物支持的反硝化（BPD）系统对低硝酸盐浓度的废水显示出良好的反硝化性能。在这项研究中，开发了使用聚（3-羟基丁酸酯-co-3-羟基戊酸酯）（PHBV）聚合物作为碳源的BPD系统，以处理高硝酸盐浓度的废水。全面研究了PHBV聚合物的反硝化性能，利用率，微生物群落结构的演变和关键反硝化细菌。结果表明，进水NO ₃ ^-- N浓度为100 mg L ^-1时，平均硝酸盐去除率可达到99％水力停留时间（HRT）为7.25小时。质量平衡模型预测，反硝化细菌会消耗80％的PHBV聚合物，实际消耗量接近72％，这表明该模型可能对BPD系统中的PHBV聚合物管理有用。此外，细菌群落结构沿生物反应器轮廓变化，这与硝酸盐和氨的浓度轮廓紧密相关。Metatranscriptomic分析确定的主要反硝化细菌为毛单胞，西瓜果和脱氯。在这项研究中开发的PHBV支持的反硝化系统显示了从废水中去除高浓度硝酸盐的潜力。