Study On Vocs Emissions Of Heat-setting(Curing) Process In Textile Dyeing And Printing Industry

Industrial VOCs emissions have always been one of the social focuses. With the development of the work of setting Emission Standard of Air Pollutants for Textile Dyeing and Printing Industry, more and more attention has been paid on atmospheric environmental problems of textile dyeing and printing industry. The major air pollutants of textile dyeing and printing industry----volatile organic compounds(VOCs) have been listed as one of the pollutant control indicators. This paper focuses on the confirmation of the emission types and source analysis of VOCs of heat-setting(curing) process in textile dyeing and printing industry.Firstly, according to the field sampling data of 5 workshops in 2 representative enterprises,we analyze the emissions of 8 kinds of VOCs like benzene series, halogenated hydrocarbon, 2-butanone etc. and TVOC in the heat-setting process and the results show that benzene series and 2-butanone are the major pollutants from heat-setting machine, whose toxicity will affect the environment and the humans greatly. According to the measured data, VOCs emissions of the heatsetting machine is about 17000 tons per year.Then we select three kinds of finishing agent(softening agent, resin agent and waterproofing agent) as 15 samples of different components. First, we use FID for TVOC determination under normal temperature and screen out the agents of large quantities of VOCs release; Second, based on the process conditions, we simulate the heat-setting process, collect the volatile gases and use GC-MS to analyze the components; finally, we use Raman spectra to analyze the compositions of the assistants, which is the source of VOCs.Through the experiment, we get the following conclusions: the commonly used softening agents are organic silicon softeners; volatilization of exhaust gases compositions in heat-setting progress are mainly aldehydes, esters, alcohols, alcohol ethers, siloxane etc.; the formaldehyde/ formaldehyde-free resin, gradually in place of the traditional low formaldehyde content, is used as resin finishing agent; volatilization of exhaust gases compositions in heat-setting progress are mainly esters, ethanol and acids; commonly used waterproofing agents are mainly fluorine waterproofing agents, among which the emission level of C8 waterproofing agent is the highest, followed by C6 and trumpets waterproofing agents; the exhaust gases of waterproofing agents are mainly halogenated hydrocarbons, alcohols, ketones, alcohol ethers, acids, perfluorinated. The main source of VOCs in heat-setting process is from the low boiling point solvent of the 3 kind assistants.