A new process for dry flue gas desulfurization and denitration has been developed

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This post was last edited by 654262293 on 2016-2-18 at 13:40. A new process for dry flue gas desulfurization and denitration has been developed. Author/Source: China Chemical Industry News; Date: 2016-02-04; Views: 41. After more than 5 years of research efforts, the industrial-scale trial of the catalytic cracking flue gas desulfurization and denitration technology (dry desulfurization and denitration trial), which was part of Sinopec Group’s research projects, has been completed. It passed the technical evaluation conducted by Sinopec’s Science and Technology Department, with Academician Cao Xianghong serving as the head of the evaluation committee. 　　This testing device directly removes sulfides and nitrogen oxides from flue gas through a catalyst. Compared with traditional wet desulfurization and denitration technologies, the new dry desulfurization and denitration technology not only offers better environmental benefits, but also features a more convenient, efficient, and economical process flow. It has advantages such as simplified equipment, reduced floor space, easy operation and management, low production costs, and no secondary wastewater pollution. 　　The test results show that the removal rates of sulfur oxides and nitrogen oxides from catalytic cracking flue gas are as high as 95% and 60%, respectively. The minimum mass concentrations of sulfur oxides and nitrogen oxides are both below 10 mg/m³, with no emission of secondary pollutants. It exhibits strong adaptability to flue gas, and the adsorbent can be used as a catalyst in catalytic cracking. 　　It is reported that this project is jointly undertaken by Sinopec Engineering Construction Company, the China Petroleum Research Institute, and Zhongyuan Oilfield. The experimental facility is located at the Petrochemical Complex of Zhongyuan Oilfield. It operates on a continuous adsorption-regeneration cycle mode, using catalytic cracking catalysts as adsorbents and hydrogen-containing or small-molecule saturated hydrocarbon media as reducing agents, in order to achieve the resource recovery of sulfur oxides into hydrogen sulfide and the harmless emission of nitrogen oxides into nitrogen gas. The testing facility has been in use for experiments since its completion in October 2013. Over the past two years, through careful adjustments by technical personnel and repeated tests, all parameters have met the expected standards, with the purified flue gas satisfying the **emission requirements. 　　It is understood that the wet desulfurization and denitrification technologies commonly used for catalytic cracking flue gas at home and abroad currently require large amounts of space, have complex post-treatment processes, and can easily cause secondary pollution of water. These technologies have begun to be phased out in developed countries and regions, and the development of dry processes for simultaneous desulfurization and denitrification has become a trend. 　　The existing dry flue gas desulfurization and denitration technologies follow an integrated approach, characterized by high overall efficiency and low land use. However, ammonia is used in the removal of NOx, which can lead to ammonia leakage and subsequent secondary pollution. As for the semi-dry process used in flue gas desulfurization in coal-fired power plants, since the adsorbent has no capacity for regeneration, it can only be disposed of after reaching adsorption saturation, resulting in solid waste. This either leads to secondary pollution or requires additional investment for further treatment. 　　The new dry desulfurization and denitration technology developed by Sinopec uses catalytic cracking catalysts as adsorbents, employing a circulating fluidized bed adsorption-regeneration process. It does not alter the existing processes or operating conditions of the catalytic cracking units, and the adsorbents can be reused. Meanwhile, after regeneration and reduction of processes such as catalytic cracking dry gas, the sulfur oxides on the adsorbent are reduced to hydrogen sulfide for subsequent utilization, while nitrogen oxides are reduced to nitrogen and emitted harmlessly. The adsorbent dust contained in the purified flue gas can be recovered using established dry dust removal methods. http://www.nmtech.com.cn/*nwen_xgyw_xx.asp?path=57&id=175305