Study On Calculation Method Of Vocs In Waste Water Collection,transportation And Treatment Unit Of Petrochemical Industry

Volatile Organic Compounds(VOCs)are a class of organic compounds that form haze precursors in atmospheric photochemical reactions.As an important emission source of VOCs,the VOCs of industrial sources are complex and toxic,causing damage to the environment and human health to a certain extent.As the national pillar industry,the petrochemical industry's VOCs management and control work has always been the top priority in many industries.Firstly,analyzing the accuracy of VOCs emission accounting coefficient of waste water source in petrochemical enterprises.China's major crude oil imports and physical properties of crude oil are different from the United States.In addition,the discharge coefficient is given by the United States in 1995,and the timeliness is poor,which can not meet the current domestic petrochemical enterprises' emission status.At the same time,the discharge coefficients of waste water collection,transportation and treatment unit have the certain scope of application.The set of coefficients are used to calculate the emission of VOCs of the entire waste water source,with low accuracy.Secondly,according to the geographical distribution,size and product types of domestic petrochemical enterprises,9 sample enterprises are selected for sampling,analyzing and accounting emissions.Under the premise of taking into account the difference between the liquid phase flashing of the collection unit and the sealing condition of the treatment unit processing tank,when the regulating tank is not covered and sealed,the VOCs emission coefficient of waste water collection and transportation unit is 0.032kg/m3.The VOCs emission coefficient is 0.0168kg/m3 when the processing tanks are not covered and sealed.The VOCs emission coefficient is 0.0143kg/m3 when separation tank,floatation tank and biochemical tank are covered and sealed but no tail gas treatment facility.The VOCs emission coefficient is 0.0044kg/m3 when separation tank,floatation tank and biochemical tank are covered and sealed with tail gas treatment facility.The VOCs emission coefficient is 0.0004kg/m3 when all the processing tanks are covered and sealed.Finally,selecting 7 petrochemical companies for verification.As for collection and transportation unit,the fluctuation of emissions calculated by the coefficient and the measured emissions are in the range of 4.0%-20.6%.The fluctuation of treatment unit emissions calculated by the coefficient and the measured emissions are in the range of 2.1%-29.4%.Water9 simulation is used to verify the rationality of the emission coefficient of the treatment unit.The fluctuation range of measured and simulated values is between 1.6%and 31.1%.