Removal Of NOx From Power Plant Flue Gas By Activated Coke

China is the foremost producer and consumer of coal in the world. Thermal power generation will inevitably remain the overwhelming indigenous way in the foreseeable future. Reducing pollutant emissions and improving the efficiency of thermal power generating unit are essential for the technology progress in the power generation industry. The control and reduction of NOx, following the removal of particulate material and SOx, has become a research highlight with the stringent requirements for environmental protection. Currently, carbon-based materials have gained extensive attention due to its inherent advantage in the DeNOx of the flue gas, such as low energy requirement, effective cost and ease integration with FGD. In order to provide necessary information for the design and optimization of the DeNOx reactor, the removal of NOx using activated coke as the sorbent is investigated experimentally in the fixed bed reactor.Firstly, lignite was used to generate activated coke by carbonization and activationl in the tube furnace. The industrial analysis, iodine adsorption, surface area and surface functional groups of the activated coke were subsequently determined by various measure methods. The results showed that the activated coke has less volatile, a large specific surface area and abundant micropore structure, which is beneficial to the acid gas adsorption.Secondly, the influence of operating parameters including temperature, space velocity and oxygen and water vapor concentration on the adsorption capacity were carried out in a fixed-bed reactor. The DeNOx rate and breakthrough time decreased with increasing the reaction temperature and space velocity. When increasing the oxygen concentration, the DeNOx rate increased at first. As the oxygen concentration is higher than 5%, the denitration rate do not increase obviously. The presence of water vapor was unfavorable for the DeNOx by activated coke.Thirdly, the DeNOx performance of the modified coke was investigated in the fixed-bed reactor. The results indicated that the CuO modified activated coke shows better DeNOx performance compared with the modification by Fe3O4 and MnO. The DeNOx performance of activated coke modified by different concentration of CuO (0.5%、1% and 2%) indicated that the activated coke with 1% CuO was optimal choice, and the adsorption capacity reached up to 2.89 mg/g. Ash content in the activated coke decreases by HNO3 ash removal; In addition, the high temperature calcination could increase the content of alkaline surface functional groups, both of which improved the removal efficiency of NOx. The activated coke modified by HNO3 ash removal and then loading different metal oxides, exhibits better DeNOx performance. Among of them, the activated coke modified by HNO3 ash removal and then loading 1% CuO shows highest DeNOx efficiency, and the adsorption capacity reached up to 3.43 mg/g.