MHI Wet-FGD Waste Water Treatment Technologies - (PPT)

摘要

Waste water generated from Wet FGD systems is considered difficult to treat in the waste water treatment system, especially selenate and/or COD that are generated in the scrubber. These compounds are treated by chemical treatment requiring huge amounts of reducing or oxidizing agent or biological treatment requiring severe control to maintain the bioactive condition in the past. MHI offers in-situ control technology by controlling Oxidation-Reduction Potential (ORP) to effectively prevent formation of these compounds in the scrubber. This technology has been already adopted to several Japanese actual plants and the discharge level of selenium Is being controlled to less than the Japanese regulation limit for years. MHI also has zero liquid discharge systems, including the Wastewater Evaporation System (WES), the Wastewater Spray Dryer (WSD) and the Wastewater Concentration and Solidification System (WCS) to reduce or eliminate discharge in order to reduce cost and meet further stringent regulations. Many actual plants have already adopted these systems and are operating favorably. This paper presents the outline of these technologies and actual plant applications.