Study Of Engineering Application On Magnesia Desufurization

Environment protection is becoming more and more important as it is industrialized. The sulfur dioxide emission on China increases continuously, which amounts the 1st in the world and exceeds the allowable environmental capacity by more than 80%. Around one third of national land are affected by acid rain caused by SO2,and 50% of SO2 emmission are from coal combution in coal fired boiler of power generation plant.So flue desulfurization is a demand for power plants which will have a large amount of SO2 emission potentially.Different desulfurization process have been compared in this paper,and magnesium desulfurization is described detailedly.Since magnesia desulfurization has following advantages: low investment and operation cost, widely usage for byproducts and no secondary ,the point of this paper is that this process is much suitable for desulfurization of middle size boiler or below and old type boiler.Principle of magnesia desulfurization have been studied which includes: process diagram, chemical reaction process,absorption mechanism of SO₂ and mass balance.And affecting factors for remand effeciency have been studied based on actual engineering application which includes: inlet SO₂ concentration, gas quantity,pH value and ratio between liquid&gas flue rate.Analysis having been done to these affecting mechanism,and optimum control type is got for this process.Solubility diffenrence and its affection on desulfurization have been analysed for the intermediates and final product MgSO₃ &MgSO₄. Experiments have been done to study the transform rate from MgSO3 to MgSO₃ based on different conditions,which will seek academic basis for the PH value control point of absorption liquid of this process.Technical and economic analysis have been done for magnesia desulfurization and other calcium based desulfurization,and the advantages,disadvantages and applicability have been discussed too.