Development Of DL-SW Micro-Cabin And Analysis Of VOCs Released From Wood-based Panels

Nowadays,indoor air pollution has become a common concern of all countries in the world.Indoor air pollution is mainly due to the decoration of the use of wood-based panels which release a variety of volatile organic compounds.Some of the volatile organic compounds,such as benzene,aldehydes,etc.,have a great harm to human health.At present,the method of collecting volatile organic compounds(VOCs)in domestic and abroad is mainly chamber method.Chamber method can simulate the VOCs release environment of wood-based panels reasonably and realistically.However,the cost of the chamber equipment is up to millions of dollars,while the detection cycle is 28 days,the detection cycle is too long led to the reduction of turnover rate.In recent years,domestic scholars began to study the rapid detection of VOCs released from wood-based panels using imported heat extraction apparatus,the method can shorten the detection cycle to 10 days or so,but because of the thermal extraction apparatus can not accurately control the relative humidity and the equipment cost nearly two hundred thousand yuan,the popularization and application of the method is facing some difficulties.In order to accurately simulate the various test environment(including temperature,relative humidity,area specific ventilation rate),reduce VOCs detection cost and shorten the test cycle,this paper introduced the development of DL-SW micro cabin.DL-SW micro cabin costs about 30 thousand yuan,has 6 test chamber and canaccurately adjustand control temperature,relative humidity,area specific ventilation rate and can be used for VOCs detection of wood-based panels.The medium density fiberboard(MDF),plywood and particleboard were taken as the research objects,this study collected VOCs released from three kinds of boards using the DL-SW micro-cabin,and used GC/MS to analyze the release characteristics,composition and concentration of VOCs.The test results of DL-SW micro-cabin and 1m~3chamber and the rapid test methodwere compared and analyzed:(1)This study detected the VOCs released from MDF,plywood,particleboard by DL-SW micro-cabin,and the results showed that TVOC emissions of the three kinds of panels decreased fastest in 1~3 days,then gradually slowed down and eventually reached equilibrium state.TVOC concentration of the DL-SW micro-cabin method under the stable state was slightly higher than that of the 1m~3 chamber method and the rapid test method,and the average deviations were 6.66%and 1.72%,respectively.(2)The detection cycle can be shortened with increased temperature and humidity or increased area specific ventilation rate.Underthe condition of 60?,60%relative humidity,1area specific ventilation rate,TVOC released from the MDF,plywood,particleboard detected by DL-SW micro-cabin reached stable state in the shortest time,which was 12 days for MDF and plywood,13 days for particleboard.Compared with the 1m~3chamber method,the detection cycle was shortened by more than half.Therefore,the conditions of 60?,60%relative humidity,1 area specific ventilation ratewere selected as the optimal conditions for the DL-SW micro-cabin.(3)The influencing degree of temperature on initial TVOC release concentration of three kinds of panels were 41.46%,165.40%,133.67%.The influencing degree of relative humidity were13.72%,43.23%,29.28%,and the influencing degree of area specific ventilation rate were 20.55%,26.43%,27.99%.In the external environment factors,the temperature has the greatest influence on the VOCs release.(4)The test results of DL-SW micro-cabin and 1m~3chamber and the rapid test method showed that the types of VOCs released from MDF,plywood and particleboard were alkenes,aromatic hydrocarbons,alkanes,aldehydes,ketones,esters,alcohols.The main substances released fromMDF,plywood and particleboard were aromatic hydrocarbons,hydrocarbons and alkenes,respectively.The initial release amount of VOCs increased with increasing temperature or relative humidity,while the area specific ventilation rate increased,the initial release of VOCs decreased.Increasing the hot pressing time can significantly increased the release of TVOC,especially the amount of aromatic hydrocarbon,and increasing the thickness of the panels,which would cause the increase of alkenes,aromatichydrocarbons,alkanes and aldehydes.The environmental performance of adhesive had significant effect on the release of aldehydes and aromatic hydrocarbons.(5)The fitting line of DL-SW micro-cabin method and the rapid test method was y=0.9892x-0.2707,the fitting degree was 0.9995.The fitting line of DL-SW micro-cabin method and1m~3chamber method was y=0.9093x+1.1367,the fitting degree was 0.9942,the correlation between these methods was good.