Study On The Application Of Wet Limestone Desulfurization In Circulating Fluidized Bed Boiler

In recent years, the technology of large circulating fluidized bed boiler is developing rapidly, and has become an important way of the efficient clean utilization of the inferior fuel in China. However, with increasingly stringent environmental standards, traditional in circulating fluidized bed boiler limestone desulfurization technology is difficult to meet new environmental standards, at the same time in furnace desulfurization limestone utilization rate is low and the boiler combustion will cause some negative impact.Based on the above research background, this paper to a type of HG-440/13.7-L.PM circulating fluidized bed boiler desulfurization transformation of Chentang thermal power plant as the object of study, comparative study of limestone wet and dry RCFB flue gas desulfurization process technology and economic performance indicators, combined with the transformation of the project feature to determine the desulfurization process for limestone wet flue gas desulphurization, and according to the actual site conditions, optimization of the process design to determine the selection of equipment. Limestone wet FGD system during the test run, the performance test of the desulfurization system, 100% and 75% respectively in the boiler load test conditions, the important parameters in the field test of flue gas temperature, moisture content, flow velocity, flow, pressure, SO₂, calculate the amount of flue gas, desulfurization efficiency, limestone consumption, Ca/S, the total pressure loss, water and electricity consumption, through chemical test method of by-product gypsum and waste water quality in the laboratory indicators, through the analysis of the test data, the results show that the desulfurization system in the slurry of Cl- content is too high, has the effect of gypsum quality and treated waste water quality, we need to further optimize. The lime stone powder of circulating fluidized bed boiler desulfurization transformation before and after consumption, SO₂ concentration in flue gas, boiler fly ash combustible exhaust gas temperature operating parameters for a month of continuous acquisition analysis.Research shows that: First, after the transformation of desulfurization system the concentration of SO₂ emission can meet the new national standards of environmental protection;Second, in the transformation of the desulfurization system, in order to meet the requirements of environmental emissions and save more than 80% of lime stone powder consumption; Third, after the transformation of the desulfurization system, the combustible material of the fly ash is decreased by 36%, the temperature of the flue gas is 10.8%, and the combustion efficiency of the boiler is improved. Finally, this paper studies the encountered in the actual operation of the limestone wet desulphurization absorption tower slurry overflow, GGH blockage, slurry corrosion in the circulating pump wear serious problem. The results show that: First., the system of desulfurization slurry quality improvement is to prevent the absorption tower foaming overflow; Second, to ensure the absorption tower in mist eliminators for normal washing, can slow the GGH jam, increase the economic operation of desulfurization system; Third, desulfurization system slurry circulating pump over flow components with high polymer wear-resisting, corrosion-resistant material coated, can slow a flow components of the wear and corrosion resistance. The research and analysis of this research have important guidance for the formulation and implementation of the desulfurization scheme of the circulating fluidized bed boiler.