Method for recovering calcium and magnesium from desulfurization wastewater by flue gas method

• Main Authors: YUE LIYI, ZHANG RUTING, LIU WENTING, CHEN CHUANMIN, KANG JIACHENG, LIU SONGTAO, YUAN WEIQIAN, HU YANGLIN, LIU ZIXUAN
• Format: Patent
• Language: Chinese; English
• Published: 04.01.2019
• Subjects: CHEMISTRY; COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM,CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THERARE-EARTH METALS; INORGANIC CHEMISTRY; METALLURGY; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

The invention discloses a method for recovering calcium and magnesium from desulfurization wastewater by a flue gas method, and belongs to comprehensive recovery and utilization of wastewater in the technical field of environmental protection. The method comprises the following steps: performing simple pretreatment on the desulfurization wastewater, then introducing desulphurization flue gas intoa carbon capture device, removing calcium ions, then adding alkali and recovering magnesium hydroxide in a precipitate by utilizing a tubular membrane. The method disclosed by the invention has the benefits that the flue gas from a power plant is reasonably utilized, the wastewater is subjected to reduction and emission reduction simultaneously, calcium carbonate is reused, the magnesium hydroxideis recovered, and the resource utilization of the wastewater is realized. 本发明公开了种烟气法回收脱硫废水中钙镁的方法，属于环保技术领域的废水综合回收利用，对脱硫废水进行简单预处理后通入装有碳捕集装置的脱硫烟气，除去钙离子后投加碱利用管式膜回收沉淀中的氢氧化镁。本发明既将电厂烟气合理利用，同时对废水减量减排，回用碳酸钙，回收氢氧化镁，实现了废水的资源化利用。