Study On Emisssion Standard Of Air Pollutants For Woodwork-making Industry

Woodwork-making industrial is an important source of volatile organic compounds(VOCs).Coatings and adhesives and other raw materials which used during the manufacturing process contain a large number of VOCs,which will cause photochemical pollution and harmful to human health.Zhejiang Province is the manufacturing center of the Yangtze River Delta,has released a series of policies about the prevention and control of VOCs pollution.However,Zhejiang Province is still lack of targeted air emission standars of wood products manufacturing industry This study proposes scientific standard system of discharge standard of air pollutants for wood products manufacturing industry.To explore the pollution characteristics and emission coefficient of volatile organic compound(VOCs)released from the woodwork-making industry in Zhejiang province,this paper used the survey data of 310 woodwork enterprises which obtained in 2015 to analyse the current VOCs treatment status of woodwork-making industry,and further screened 213 key enterprises to study the emission coefficient of woodwork-making industry.The results showed that more than 94% of woodwork enterprises failed to effectively dispose VOCs due to most woodwork enterprise did not have treatment facilities.Moreover,solvent-based materials such as adhesive and paint was still commonly used in woodwork-making industry.Meanwhile the main pollutants of VOCs in woodwork-making industry were xylene,butyl acetate,ethyl acetate,toluene and formaldehyde.Among them,BTEX were the main contributors to the generation potential of ozone and secondary organic aerosols in the industry.Furthermore,the VOCs emission coefficient of woodwork-making industry in Zhejiang was 93.4 g(million Yuan)-1,while it was affected by the production processes,and the coating techniques was higher than the adhesive techniques,which VOCs emission coefficients were 93.6 g(million Yuan)-1 and 9.5 g(million Yuan)-1,respectively.Furthermore,the major polluting stage of woodwork-making industry was coating techniques,which VOCs emission coefficients was 31.0 g(million Yuan)-1 when using waterborne and UV coating.While the highest VOCs emission coefficients was from manufacture wooden furniture,which could reach 168.5 g(million Yuan)-1 with using solvent-based coatings.At last,we estimate the emission of VOCs and O3 are 83.6 thousand tons and 274 thousand tons,respectively.Base on the study above,“Emission standard of air pollutants for wood product manufacturing industry” was drafted,it indicated that the specific control index are as follows: resin dust(paint mist),wood dust,benzene,formaldehyde,styrene,acetates,BTEX,VOCs and odor concentration.New source,special emission limits,fugitive emission limits were included in the standard: resin dust(paint mist)(30 mg/m~3,15 mg/m~3,1 mg/m~3),wood dust(20 mg/m~3,10 mg/m~3,1 mg/m~3),benzene(1 mg/m~3,1 mg/m~3,0.1 mg/m~3),formaldehyde(4 mg/m~3,2 mg/m~3,0.1 mg/m~3),styrene(10 mg/m~3,5 mg/m~3,0.2 mg/m~3),acetates(40 mg/m~3,30 mg/m~3,2 mg/m~3),BTEX(40 mg/m~3,30 mg/m~3,2 mg/m~3),VOCs(60 mg/m~3,40 mg/m~3,2 mg/m~3),odor concentration(800 mg/m~3,500 mg/m~3,20 mg/m~3).