关键词: 煤化工过程, 污染特征, 资源经济, 环境战略

Abstract: The basic principles of coal chemical processes were reviewed in this paper including coal carbonization,coal-to-coke,coal-to-gas and coal-to-oil,and the product direction of coal chemical process was analyzed. The reasons of main pollutants produced by coal chemical process were introduced from the coal properties,the process requirements,and the technology features. The source and composition of the “three wastes” were selectively analyzed from the processes of coal-to-coke and coal-to-gas. Among them,the waste gas came from the incompletely carbonized pulverized coal in the chemical conversion process,the precipitated matters including volatile matter,tar fog and fly ash,the leaked raw gas,as well as CO,CO₂ and NO₂ generated by burning coke on contact with air. The wastewater included dedusting wastewater,surplus aqueous ammonia,phenol and cyanogens wastewater,desulfurization liquid and the water sealing gas. The waste residue included dust,coal dust,acid tar,tar slag and sludge. The gas phase pollutants from coal chemical process mainly included oxycarbide,oxysulphide,ammonia gas,volatile phenol,benzene,benzopyrene,CO,CH₄ and small molecule hydrocarbons. The liquid phase pollutants contained not only ammonia,cyanide,sulphide,benzene,phenol and oil,but also a lot of benzopyrene,naphthalene and other PAHs,and heterocyclic aromatic hydrocarbons including pyridine,carbazole,biphenyl,terphenyl,etc. The pollution characteristics showed wide distribution,complex components,high concentration,coexistence of multiphase mediums with high environment risk. The typical characteristics of the coal chemical wastewater were high concentration/salinity,high pollution (multicomponent),toxic and refractory. The clarification of the relationship between the coal chemical process and pollution characteristics needed researchers to deepen the comprehensive understanding for the basic coal properties,the principles of conversion,purification and application. Therefore,the control technology and strategy should be based on the deep understanding for the chain of resource- product-economy-environment-society and the effective integration system,and the strategic design and logic innovation should be enhanced through the scale,product,technology,management,market and talent.

Key words: coal chemical process, pollution characteristic, resource economy, environment strategy