Advanced treatment technology for FGD wastewater in coal-fired power plants: current situation and future prospects.

At present, the desulfurization wastewater produced from flue gas desulfurization (FGD) has complex compositions, discharging of FGD wastewater results not only consumption of large quantities of water resources but also destruction of the environment. With the implementation of "The Action Plan for Prevention and Treatment of Water Pollution" in China, the discharging requirements for FGD wastewater from coal-fired power plants are increasingly stringent. Besides, the traditional chemical precipitation method can no longer meet the needs of the current "zero discharge" policy. Thus, advanced treatment of desulphurization wastewater has become an inevitable trend. It is necessary to analyze the existing advanced treatment technologies for desulfurization wastewater and find out the difficulties and problems existing in these technologies. Then, the rationalizations of these technologies will be proposed, and improvable system will be designed as well as the goal of "zero discharge" achieved gradually. This paper will discuss the characteristics of desulphurization wastewater and introduce the current status of existing wastewater treatment techniques by comparing their advantages and disadvantages. In the end, combined with technologic development and the analytic results above, a new concept of "thermal membrane hybrid method" is being proposed. [ABSTRACT FROM AUTHOR]