A compound desulfurizer for oxidizing elemental mercury and removing hcl and its preparation method

Abstract

A compound desulfurizer for oxidizing elemental mercury and removing HCl and a preparation method thereof, comprising bicarbonate 15-30%, BaCO32-5%, KMnO40.5-2%, CeO20.5- 2%, the rest is Ca(OH)2. During preparation, the calcium hydroxide, sodium bicarbonate, barium carbonate and potassium permanganate are pulverized respectively, and then the raw materials are uniformly mixed according to mass percentage. The preparation method of the composite desulfurizer is simple and feasible, and only one set of feeding and injection systems is needed in practical engineering applications to meet the needs of desulfurization and mercury removal. The composite desulfurizer of the present invention has better medium-temperature desulfurization efficiency. In the temperature range of 300-420°C, the SO2 removal efficiency is over 95%, and the SO3 removal efficiency is over 90%; the oxidation efficiency of elemental mercury reaches 80%. 95%; the removal efficiency of HCl reaches over 90%.

Description

technical field [0001] The invention relates to a desulfurizer for removing SOx, HCl and elemental mercury in flue gas, in particular to a composite desulfurizer for oxidizing elemental mercury and removing HCl and a preparation method thereof. Background technique [0002] Boilers or thermal power plants that use coal and oil as fuel emit a large amount of flue gas every year. These flue gases contain harmful substances such as SOx, NOx, HCl and HF, among which sulfur oxides include SO 2 and SO 3 , they are the main substances that form acid rain. [0003] With the development of my country's industry, the emission of sulfur dioxide in industrial flue gas is becoming more and more serious, and the damage caused by sulfur dioxide to the environment and human body has gradually been valued by the state and society. Therefore, a variety of flue gas desulfurization technologies have emerged as the times require. Imported from abroad or developed independently, they can be div...

AI Technical Summary

Problems solved by technology

[0008] The wet desulfurization system with high desulfurization efficiency is more complicated and the operating cost is higher, while the traditional dry and semi-dry desulfurization methods are relatively convenient to operate, and the desulfurization efficiency of the desulfurizer is relatively low. desulfurization agent, which has important economic and environmental significance for reducing labor and cost input in desulfurization industries

[0009] The adsorption process itself is an exothermic process, and high temperature is an unfavorable factor for this process, which will also lead to a decrease in desulfurization efficiency

Such as temperature vs. NaHCO 3 The desulfurization process is greatly affected, and the desulfurization effect is better when the temperature is lower than 150 °C. When the temperature is increased to 300 °C, the desulfurization efficiency will be significantly reduced, and it cannot meet the SO 2 environmental indicators

At present, the adsorbents or catalysts for the removal of elemental mercury under the condition of coal-fired flue gas mainly include carbon-based adsorbents such as fly ash, activated carbon, and modified activated carbon, etc., and their activation temperature window is narrow. ) The mercury removal efficiency is low and cannot be used for mercury removal in this temperature range