Solution Equilibrium Characteristics Of Metal Ion In Sodium Alkali Desulphurization Recycling Liquid

In flue gas desulfurization with membrane electrolysis and sodium alkali recycling, sulfuric acid used broadly as industrial raw materials is by-product. The quality of sulfuric acid decides its market; therefore, for different key element combination the quality of sulfuric acid is the basic and necessary requirements for resource of by-productosition and related to the actual application of the desulfurization process. The particularity of the regernaration of fertile liquor from desulfurization process is that there exist dissolution and precipitation equibriums of metal ions in the absorbent. Precipitation will affect the operation of equipment; on other hand, dissolution will affect the regeneration of the by-product.The relationships between the existence characteristic and maximum content of metal ions and the operating condition and the various metalic ion interational actions were investigated. First of all, the solubility for various single metal ion in different concentration sulfuric acid liquor was theoretically analyzed,then experimentally determined, at last the relations between the maximum metal ion concentration in sulfuric acid liquor and the operating conditions, the actual input content, the measuring conditions and the priciptation time were analyzed.The results from experiments about relation between maximum matal ion content and operating conditions showed that actual dosage of metal element influenced metal ion content in sulfuric acid solution greatly. For magnesium, aluminum and iron ions, the ion contents in solution were in agreement with their actual dosage. For low concentration sulfuric acid solution, the actual amount of magnesium, aluminum and iron ions are larger and magnesian, aluminous and iron ion contents in the solution are greater. For 80% and 98% sulfuric acid, the results are just the opposite. For calcium ion, when sulfuric acid concentrations are 25%, 40%, 50% and 80%, respectively, the dosage of added calcium is greater, and the calcium ion in solution is smaller. When sulfuric acid concentration is 80%, the actually added dosage of calcium is 1.0643g/L, and the calcium ion content in the solution is 0.691g/L.Different measuring methods have great influence on calcium ion concent. At the same time, Magnesian, aluminous, calcium and ferreous ion contents were affected by sedimentation time. But calcium and ferreous ion content is more pron to be affected by pricipttion time.