| Coking industry which is the process of organic matter carbon zoom (in the high temperature carbonization of coal carbonization finger) is the foundation,precursor and key point of coal chemical industry, and chemical products generated in the coking process through recycling and processing extract tar, ammonia, naphthalene, hydrogen sulfide and other products, and get the net coke oven gas, coal tar, etc. Whereas, our country is lack of oil, natural gas and rich of coal, so it has become a hot issue to develop coking industry concerning the increasing demand for energy. However, there exist some environmental risks such as fire, blast, toxic leakage in this industry because high temperature and pressure must be applied when coal is gasified, and its products have characters of combustibleness, explosiveness and high toxicity, also the potential risks are caused by transporting and storing huge sum of those products, therefore, in order to reduce environmental accident risk and loss of environmental risk ,it is the right time to launch environmental risk assessment in coking industry. In this paper, the core is the study on the way of atmosphere environmental risk assessment of coking industry, combined with the characteristics of the risk of coking industry. The main conclusions of this paper are listed as follow:Firstly, combing the features of the coking industry, various types of risk characteristics were identified. Results show that there are fire, explosion, leakage and Hazardous Substances release to the atmosphere or the body of water. On that basis, environmental risk assessment procedure of coking industry was built which was applicable to environmental risk assessment system.Secondly, the environmental risk assessment of a Typical Process coking industry was researched. Adopting the Technical method starting from risk identification, source analysis, results calculation to final risk analysis and characterization, several types of risks in the coking industry were analyzed in detail. Results showed that leakage was the main risk of the coking industry and the main risk substances were methanol, carbon monoxide, ammonia, hydrogen sulfide, benzene and BaP which come from raw gas, benzene, ammonia and tar, etc. The biggest accident probability of raw gas leakage was 3 times/year comparing to benzene which was 1×10-5. Finally adopting a typical coking project, environmental risk analysis was carried out. Results show that the value of the personal risk of pyrene was much higher than the toxic substances of the body. Within the research the risk value of the coking project was 1.25 10-7/a. Although the risk value was less that the maximum acceptable level which was 1 10-6/a, the risk value was much higher than that of other regions. For the new coking project of that region, there was risk of cancer round the coke oven under normal condition particularly within 800m of the coking furnace. Under adverse weather conditions, cancer risk was much higher than that under wind conditions. There was certain relevance between the benzopyrene round the coking plant and the local dominant wind direction. Therefore, reasonable layout planning of the coking plant could significantly reduce the risk of cancer.
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