火电厂脱硫废水微滤、反渗透膜法深度处理试验研究

为使电厂脱硫废水循环使用并达到废水零排放目标，采用“微滤（MF）-反渗透（RO）”工艺对预处理后的火电厂脱硫废水进行深度处理，分别考察不同固含量条件下微滤系统的运行稳定性和微滤膜的化学清洗方法，以及不同回收率条件下反渗透系统的运行稳定性和脱盐率情况。研究结果表明：经中和软化处理的脱硫废水再经微滤处理后，产水浊度小于0.2 NTU，膜污染指数SDI值小于4.0，微滤系统运行稳定；反渗透系统在不同回收率条件下运行稳定，无明显的污堵现象，系统脱盐率大于98%，单支膜的脱盐率大于99%。反渗透产水含盐量低于510 mg/L，可用作循环水补充水、脱硫工艺用水等电厂其他系统的补水。

Experimental Study on the Reduction Treatment of Desulfurization Wastewater in Power Plants by Membrane

To recycle the desulfurization wastewater and achieve the goal of zero wastewater discharge in power plants, the desulfurization wastewater after pretreatment is treated by adopting microfiltration(MF) and reverse osmosis(RO). The stability of MF system and the chemical cleaning method of MF membrane under different solid content conditions are explored as well as the stability and desalination rate of RO system under different recovery rate conditions. The study results show that the MF system can operate stably and the turbidity of its water production is less than 0.2NTU with the silt density index(SDI) less than 4.0. The RO system also operates stably without obvious scaling observed under various recovery rate conditions. Its desalination rate is more than 98%, and the desalination rate of single RO membrane is more than 99%. The salinity of its water production is less than 510 mg/L, which means that the water production can be used as the make-up water for the recycled water as well as the replenishment for other systems in the power plant such as the desulfurization processing water.