Dust off and integration

In China’s one-time energy consumption, coal accounts for 70%, and coal-fired smoke and dust emissions are the major sources of air pollution in China. A project named "Integrated Process Technology and Equipment for Coal-Fired Flue Gas Dust Removal and Desulphurization" has recently passed the expert appraisal of the scientific and technical appraisal meeting convened by China High-tech Industrialization Research Association.

The Nankai University School of Environmental Science and Engineering cooperated with Tianjin Tianli People's Gas Purification Engineering Co., Ltd. and other companies to develop the “Integrated Process Technology and Equipment for Coal-fired Flue Gas Dust Removal and Desulphurization” and conducted long-term experiments in Tianjin Yangliuqing Power Plant.

Test data from the National Key Laboratory of Urban Suspended Solids Control, Tianjin Environmental Protection Bureau, etc. show that this technology can contain all soot particles (including PM2.5) entrained by coal-fired flue gas, sulfur dioxide, nitrogen oxides, and nitrogen oxides, and purification processes. The secondary pollutants produced are completely separated and recovered. The chimneys emit CO2 gas that is colorless, transparent and highly pure.

The appraisal committee consisting of 15 experts concluded that the results confirmed both theoretically and experimentally that in the current wet flue gas desulphurization process of conventional coal-fired flue gas, there is indeed a soluble hydrogen sulphate in the entrained droplets of flue gas. Bisulfite and other phenomena, and make a considerable part of the sulfur content eventually enter the atmosphere.

The project adopts gravity overflow oxidation technology to solve the problem of optimal desulfurization temperature; adopts series integration technology to achieve energy conservation and save space; according to the theory of multiphase flow, the technology and theory of fog drop increase are proposed to increase the fog. Drop and remove the purpose. This achievement integrates wet electrostatic augmentation technology and overflow oxidation technology, and it has developed a set of integrated flue gas purification process and equipment (environmental chimney), and the purification effect has reached the domestic leading level.

Professor Zhang Pu, a senior engineer at the Coal Planning and Design Institute, said that this technology is composed of three particle-size particles of an invention patent and gravity overflow oxidation technology, consisting of "artificial rain", dust removal, and desulphurization integration, in a chimney. Complete the entire purification process. The flue gas purification and discharge use a chimney to purify almost “zero” land; the flue gas purification process is short, the flow rate is low, and the resistance is small. Compared with other dust removal and desulfurization technologies, the power consumption is reduced by 30% and the investment is reduced by 20%. Relatively safe operation cycle is extended by 50%.

Zhang Pu said that with this technology and equipment, even if the coal-fired power plant has high ash content and high sulfur content, the treatment effect is the same, promoting the use of high-sulfur and high-ash coal, and reducing the cost of power generation.