Evaluation Of Key Technologies Of Mercury Emission Reduction And Cleaner Production In PVC Industry

PVC is a thermoplastic resin with vinyl chloride as monomer and produced by various polymerization methods.Because of its heat resistance,wear resistance,corrosion resistance and other advantages,it is widely used in electronics,industry,agriculture and other fields.Calcium carbide method is the main method of producing polyvinyl chloride in China,and it is also one of the production methods with the largest amount of mercury.A large amount of waste water containing mercury,waste activated carbon and waste mercury catalyst are produced in the production process,which causes harm to the environment and human health.Therefore,how to reduce the generation of mercury-containing waste and effectively deal with the mercurycontaining waste has become an urgent problem to be solved by the calcium carbide PVC industry.Through literature review and field investigation of advanced enterprises,combined with process flow and mercury production nodes,this study sorted out the existing catalyst technology,acetylene gas cleaning technology,gas phase mercury removal technology and mercury containing wastewater treatment technology;by using the multi-attribute comprehensive evaluation method,the evaluation index framework is established and the weight is set from the quantitative(resources and energy consumption,pollutants,economy,technology,etc.)and qualitative(expert scoring)directions,and the advanced technologies in each link are evaluated and studied.The research results show that under the current technology conditions,catalyst technology,acetylene cleaning technology,gas phase mercury removal technology and Technology for treatment of wastewater containing mercury in the highest ranked respectively as the copper-based catalyst,acetylene cleaning technology with concentrated sulfuric acid as reagent,New high efficiency mercury remover and pretreatment + mercury and heavy metal capture technology.The technical evaluation results can provide effective support for the carbide polyvinyl chloride industry to choose the appropriate mercury emission reduction technology in practical application.