焦化项目环境风险评价要点解析

焦化项目工艺复杂,环境风险较大,然而目前焦化环境风险评价过程中存在标准选取、模型选用等方面的不足。以西北某240万t/年焦化项目为例,通过风险源项分析、污染气象条件假定及预测模型选取等方面分析和探讨了此类项目环境风险评价的重点和技术要点。项目确定最大可信事故为粗苯泄露扩散,采用AEGLs标准并增加LC50作为比较,通过重质气模型对其预测,结果表明采用LC50标准计算结果明显偏小,存在适用局限性。根据预测结果项目需要对边界外900~1 990 m内的敏感点进行风险防范。

ANALYSIS OF ENVIRONMENTAL RISK ASSESSMENT FOR COKING PROJECT

Coking project process is complex，and the environmental risk of the production process of coking is bigger． The present situation of the coking process environmental risk assessment exists some insufficient， such as standard selection and model selection， etc． The paper taking a 2. 4 million tons /year northwest coking project as an example， through the risk source analysis， the pollution meteorological conditions assumed and prediction model selection，analyzed and discussed the focus and technical key points of environmental risk assessment． The project determined the maximum credible accident for coarse benzene leakage diffusion and adopt AEGLs as risk standard and LC50 for comparison． Through the heavy gas model to predict， the results showed that the standard of LC50 calculation was significantly small and limited． According to the prediction，this project need risk prevention within the scope of project boundaries from 900 m to 1 990 m．