关键词: 炼焦, 挥发性有机物, 逐级制冷, 循环净化, 资源回收

Abstract: Volatile organic compounds (VOCs) in a coking plant in Inner Mongolia contain high concentration of non-methane total hydrocarbon, benzene, benzopyrene, organic compounds containing chlorine and fluorine, as well as a large amount of hydrogen sulfide, ammonia and other inorganic compounds. The organic pollutants have high concentration, high toxicity and complex composition. There is still a lot of room for improvement in many VOCs processing technologies. Through the development and application of VOC treatment technology, the high exhalation concentration of non-methane total hydrocarbon, benzene, benzo pyrene and ammonia in VOCs were effectively solved. The chemical components in VOCs were recovered by cyclic refrigeration step by step through the vent at the exhaust cylinder of the mechanical slag scraping tank, the emission concentration of non-methane total hydrocarbon is less than 10 mg/m3, and the emission reduction efficiency of VOCs is more than 99% according to the monitoring results. During the whole treatment process, the condensing equipment is in a closed operation state, without adding any chemicals, and no new pollutants are generated, which makes the VOCs treatment achieve environmental protection and zero emission, providing an engineering demonstration for the treatment of VOCs in coking plant.