Characteristics Of VOCs In The Process Of Waste Rubber Reclaiming And Its Impact On The Surrounding Area

Volatile organic compounds?VOCs?have been paid increasingly attention due to their primary and secondary environmental pollution,and were mainly from industrial emissions.Therefore,identifying the impacts of VOCs on environment in industrial park was important for regional pollutants reduction.In this study,VOCs samples at the Yanwu Rubber Industrial Park and surrounding area were collected by SUMMA canisters from October 25 to November 8,2019and analyzed by gas chromatograph-mass spectrometer.The emission characteristics of VOCs from different processes in the reclaimed rubber plants,the spatial-temporal distribution and composition of VOCs at the surrounding area were analyzed.In addition,the patterns of the pollution event under the dominant wind conditions were also analyzed.The ratio analysis,positive matrix factor analysis model?PMF?and potential source contribution factor method?PSCF?were used to identify the potential source of VOCs in the receptor region.Meanwhile,suggestions were put forward for the management and control of the rubber industry.The main conclusions were as follows:1.A large amount of organic waste gas was resulted from the high temperature production,the use of chemical additives and the long-time exposure of the rubber powder in the production process of reclaimed rubber.The concentration level of VOCs was higher in the devulcanizing and refining process.The aromatic hydrocarbons dominated in all crafting processes?more than 99%?,in which naphthalene from coal tar was the most important substance.2.The pollutants were mainly affected by the emission of pollution sources in this area.The concentration level of pollutants?except for O₃?is high at night and low in the daytime.Alkanes and aromatic hydrocarbons were the main substance,among which naphthalene was most abundant,followed by ethane,ethylene,propylene,acetylene and benzene.3.In the pollution event,VOCs in the ambient air were mainly affected by the emission from the reclaimed rubber plants.Under the prevailing wind,Yanwu Town and Xiangle Village are more affected by the emissions from the recycled rubber plant,and the transportation of pollutants emitted by this pollution source can be observed.4.This area is mainly affected by the sources of combustion and local emissions,according to the ratio of toluene to benzene and the ratio of p-xylene to ethylbenzene.The result from the PMF model show that VOCs were mainly from coking sources?32.1%?,reclaimed rubber plant sources?29.51%?,vehicles and LPG/NG sources?21.01%?,and combustion sources?17.38%?.The results of PSCF model show that the VOCs were mainly from the western regions?within60km?of the receptor,potentially including the emissions from the rubber industry parks and vehicles etc.,and also influenced by the emissions from the coking parks in the southwest and southeast regions?within 30km?.5.Based on these conclusions,some advices on the raw and auxiliary materials,crafting process improvement,treatment of solid and hazardous wastes and utilization of treatment facilities were proposed for the regenerated rubber industry.Moreover,related supervision measures were put forward for the control of raw and auxiliary materials in this industry and enterprises illegal production.