Research Of Flue Gas Desulfurization System And Control Technology

For a long time, coal is dominated in Chinese energy structure, which accounts for70%of the totalenergy. To varying degrees, the coal in our country all contains sulfur. The coal’s directly burningwithout been processed will produce a large number of SO₂, and it will cause serious environmentalpollution. With the increasing emissions of SO₂, the harm of acid rain is becoming more and moreserious. For example, it aggravates the deterioration of ecological system, destroies the agriculture andhuman health and has severe impact on the sustainable development of social economy. The emissionsof SO₂mainly come from thermal power plants, which accounts for1/3of the national total emissionsof SO₂in our country. And the technology of flue gas desulfurization is still in its infancy. Besides, moreand more new coal-fired power plants have been built by government as the result of lack of powerresources in recent years. Therefore, it is becoming more and more important and urgent to take greatefforts to control SO₂.At present, the widespread using technics of flue gas desulfurization（FGD） mainly are: limestone-gypsum wet FGD, spray drying FGD, circulating fluidized bed FGD, Seawater FGD, electron beamFGD. From the perspective of system design, debugging and application, this paper presents someresearch about the technology of FGD for limestone-gypsum wet FGD system. Firstly, this paperdiscribes the process-design of FGD. Based on corresponding desulfurization system design, the papersets up a FGD system with reasonable structure and stable performance by calculating parametersaccording to the related technical parameters of flue gas flow, flue gas SO₂concentration, requirementsof SO₂concentration after purification, changing range of boiler load, system resistance, water-gas ratio,service life of main equipment and other basic data. Then the paper does some research aboutdesulfurization system control technology and accomplishes the FGD platform by reasonable selectionof the control method and control components. On the basis of the selection and adjustion of PH amdtemperature which have impact on desulphurization performance, the control accuracy and theefficiency of FGD system are improved by debugging the control platform. And under the satisfactionof automatic control, display, record and the other basic requirements of desulfurization process, itstrives to achieve the purpose of optimizing FGD control technology by studying of FGD controltechnology. Finally, the paper does some FGD debuggings. By using the desulfurization system whichhas already been built and adjusting some important parameter such as PH, process water, absorptiontower level, it can achieve the harmonization between desulfurization system and the equipments, and inthe end, the FGD system could keep steady state for operation..