PVDF膜接触器在电厂含氨废水处理中的应用研究

Application research of PVDF membrane contactor in the treatment of ammonia-containing wastewater in power plants

燃煤电厂含氨废水具有水量大、氨氮浓度高、水质波动大的特点,常规脱氨工艺处理困难.本文采用PVDF膜接触器处理燃煤电厂高浓含氨废水,考察了膜接触器类型、水侧流量、气侧真空度、气液接触面积、进水水质等因素对脱氮效率的影响.结果表明,基于PVDF膜接触器的气液分离工艺,能够将高浓含氨废水中的氨氮浓度由1 250 mg/L降至300 mg/L以下;外压式和内压式膜接触器都有理想的应用效果;提高膜接触器水侧流量、气侧真空度能够有效提高NH3传质效率;增大传质膜面积能够显著提升循环液氨氮脱除率.提出了分离NH3在燃煤电厂的多种资源化回用途径,为膜接触器的工程化应用提供参考.

The ammonia-containing wastewater from coal-fired power plants has the characteristics of large water volume,high ammonia-nitrogen concentration,and large water quality fluctuations,making conventional ammonia removal processes difficult to treat.In this paper,PVDF membrane contactor was used to treat high-concentration ammonia-containing wastewater from coal-fired power plants.The effects of membrane contactor type,water flow,gas vacuum,gas-liquid contact area and influent water quality on nitrogen removal efficiency were investigated.The results show that the gas-liquid separation process based on PVDF membrane contactors can reduce the concentration of ammonia nitrogen in high-concentration ammonia containing wastewater from 1250 mg/L to below 300 mg/L.Both external and internal pressure membrane contactors have ideal application effects;The mass transfer efficiency of NHs can be effectively improved by increasing the flow rate of water side and the vacuum degree of air side;Increasing the mass transfer membrane area can significantly improve the removal rate of ammonia nitrogen in circulating liquid.Multiple resource utilization pathways for separating NH in coal-fired power plants have been proposed,which provides reference for the engineering application of membrane contactors.