Environmental Risk Identification And Prediction And Prevention Strategies For A Heavy Oil Catalytic Pyrolysis Process Project In Daqing

For years, great contributions had been made by the petrochemical enterprises tonational construction. As the pillar and energy industry of China, petrochemical industryhas a great effect on the development of national economy. But the petrochemicalindustry is also a high-risk industry. It may cause harm to the environment, staffs andresidents when the accident occurred. Therefore, doing research on environmental riskidentification and prediction and prevention strategy of petrochemical enterprises to bebuilt is meaningful.This paper takes a heavy oil catalytic pyrolysis project in Daqing as the researchobject, making environmental risk identification under the condition that the design dataand peripheral distribution of sensitive points are consulted. We determined thedangerous chemicals through the material risk identification. The dangerous chemicalsinclude8kinds of flammable liquid such as naphtha and7kinds of flammable gas suchas liquefied petroleum gas. We determine the major risk sources are800Kt/a catalyticreforming device,700Kt/a device and storage area through major hazard identification.The identification results are1.5962,1.5116and6383.96. According to the researchresults and the maximum credible accident, we identified the risk sources including thefire accident of naphtha and methanol in tank, the explosion accidents of Liquefiedpetroleum gas, ethylene, propylene and1-Butene, the leakage accident of methanol,toluene, ethylbenzene, xylene, benzene and hydrogen sulfide. Then we analyzed thesource intensity of leakage accident under the condition that the atmospheric stability F,wind speed are0.2m/s,1.5m/s and3.3m/s.In this paper, it took environmental risk prediction and analysis for the project risksource, the results showed that: the damage radius is20.6m in methanol fire accident,there are no person taking long term operation in this area, and it will not causecasualties basically. The liquefied petroleum gas explosion cause the most seriousconsequences in flammable gas explosion accident, die radius, injuries radius and minorradius were17.3m,49.0m and87.9m respectively. There are no person taking long termoperation in this area, and it will not cause casualties basically. In toxic spill accident, itdidn’t appear the phenomenon that the concentration of toxic substances exceeded halflethal concentration in the atmospheric environment. The area where exceeded shortterm exposure limit was basically in the factory, when accidents happened, it could behandled in time, which will not cause casualties. Methanol, dimethylbenzene, benzeneand hydrogen sulfide leakage would cause that the contribution to the concentration atsensitive point exceeded momentary maximum allowable concentration in residentialarea. Therefore, the accident must be handled in the first time, and put forward thesuggestion that the sensitive point which is400m distance from the plant boundary must be moved.Based on the research results of environmental risk assessment, the author putforward the prevention and control strategy of the project, including tank field safetyprevention strategies, transportation safety prevention strategies, process design safetyprevention strategies, relocation program, fire-fighting measures and contingency plans,which could prevent possible accident, deal with occurred accidents, achieve thepurpose of protecting the environment and human health.