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At present, coal is the main primary energy national conditions of China's coal-fired power generation in the electric power industry occupies a position of subjectivity, and the resulting coal pollution has been the focus of environmental pollution in China, where the control of sulfur oxide emissions Governance is an important content of coal pollution, and wet flue gas desulfurization its mature technology, high efficiency desulphurization coal-fired power plants are widely used. Accumulation of large amounts of solid industrial waste emissions, pollution of the surrounding environment, if the use of the desulfurization can not only reduce environmental pollution caused by waste accumulation, but also reduce the cost of desulfurization, environmental benefits and economic benefits are very substantial. In this paper, wet FGD industrial applications for the purpose of dissolving the solid industrial waste characteristics and desulfurization characteristics were studied. Select several industrial sectors in Shandong province solid industrial waste, including spent caustic from the chemical industry, salt, mud, white clay, calcium carbide slag, waste water treatment; metallurgical industry from blast furnace slag, red mud, magnesium slag; from power industry of fly ash, slag as a test material, and use two kinds of limestone and magnesite ore as a contrast substance. Firstly, in the wet desulfurization test bed desulfurization test the basic material properties were studied by desulfurization efficiency, desulfurization saturation time, and comparative analysis of industrial waste before and after desulfurization reaction phase composition, screened with better desulfurization capacity waste. The results showed that: carbide, white clay, magnesium slag, salt, mud and caustic magnesite are five kinds of industrial waste as well as a longer period of time can maintain a high desulfurization efficiency can be used as wet desulfurization agent; Although the red mud has a higher desulfurization efficiency, but because in the desulfurization process will generate a large amount of solid precipitation, not suitable for wet desulfurization agent; fly ash, slag, blast furnace slag, waste water treatment these types of waste matter desulfurization capacity is relatively poor, and it is not used directly as a desulfurization agent. Secondly, the paper screened out as wet desulfurization waste were dissolving properties and characteristics of desulfurization for industrial waste wet FGD system environment itself and the characteristics of the slurry pH, temperature, particle size, SO 2 inlet concentration, liquid-gas ratio on the dissolving properties and desulfurization characteristics were studied to determine the industrial waste as a desulfurization agent of the optimum operating parameters. The results showed that waste as wet FGD system desulfurization agent, the caustic slurry pH value can be selected between 5.5 and 7.5; magnesium slag slurry pH of 5 to 7.5 you can choose between; Nai, salt mud, magnesite carbide and pH of the slurry can be selected between 4 to 7.5, when the desulfurization agent can achieve high desulfurization efficiency. Combination of temperature on the dissolving properties and desulfurization characteristics, caustic magnesite absorption temperature can be controlled at 60 ℃ ~ 90 ℃; salt mud, white clay, and the absorption of magnesium slag temperature can be controlled at about 60 ℃; carbide slag absorption temperature can be controlled at 30 ℃ ~ 60 ℃ range. Higher SO 2 inlet concentration causes the desulfurization effect is reduced. Improved liquid-gas ratio between liquid and gas can increase the effective contact area is conducive to the desulfurization efficiency, but will increase the ratio of liquid to gas wet desulfurization equipment investment and operating costs increase, therefore, the use of solid industrial waste desulfurization , considering all factors, while ensuring high desulfurization efficiency of the premise, can be appropriately reduced liquid-gas ratio. Finally, we study the addition of magnesium sulfate and adipic acid and caustic magnesium slag desulfurization performance. The results showed that the solid industrial waste slurry was added magnesium sulfate and adipic acid not only can improve the desulfurization efficiency, but also the buffer sorbent slurry pH reduction, the desulfurization agent slurry at lower pH level to be more high desulfurization efficiency. In the desulfurization process waste, slurry pH value decrease can be divided into three phases, namely phase high pH, ??the pH buffering intermediate stage and the low pH stage additive role mainly after the pH of the intermediate buffer stage and low pH stage. Magnesium sulfate was added to promote dissolution of the particles in the waste, as the reaction proceeds, the addition of Mg 2 form a strong activity in the slurry neutral MgSO 3 0 < / sup> 对, MgSO 3 0 formation and regeneration on the desulfurization efficiency has played a significant role in promoting. Adipic acid at low pH values ??phase slurry affect the pH effect was evident, with the organic acid is added due to the snubber can play the role of a drop in pH slurry.
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