松材室干过程中VOCs释放规律研究

Study on the VOCs Release Rule of Pine Wood During Chamber Drying

木材干燥排放的尾气因含有对环境有害的VOCs而备受关注。以企业实际运行的木材干燥过程为研究对象,采样研究了松材在室干过程中VOCs的释放规律,包括VOCs采样方式、采样时间以及采样点对VOCs释放的影响。结果表明:松材在室干过程中释放醛类及萜烯类等化合物25种,其中甲醛与乙醛浓度高于国标规定的污染物排放浓度限值,苯与丙烯醛浓度低于排放限值;采样40 min测得的VOCs释放量高于采样20 min;不同采样点的VOCs释放量有差别;采样方式对VOCs释放无明显影响。总有机挥发物释放量呈先升高,后降低,再升高的趋势,在含水率为30%左右达到最大。

The exhaust gas emitted during wood drying has attracted more and more attention because it contains some VOCs which are harmful to the environment.In this paper,taking the wood drying process in actual operation of the enterprise as research object,the release rule of VOCs in the room drying process of pine wood was studied,including the effect of sampling method,sampling time,and sampling point on VOCs release.The results showed that 25 kinds of aldehydes,terpenes,and other compounds were released from pine wood in the process of drying.Among them,the concentration of formaldehyde and acetaldehyde exceeded the limit of pollutant emission concentration specified in the national standard,and the concentration of benzene and acrolein did not exceed the limit of concentration emission specified in the national standard.More VOCs were released by sampling for 40 min than by sampling for 20 min.The amount of VOCs released between sampling points was different.The sampling method had no obvious effect on VOCs release.The release of total organic volatiles increased first,then decreased,and finally increased,and reached the maximum value when the water content was about 30%.