在(zai)用(yong)多孔性固體(ti)(ti)物質(zhi)處理流體(ti)(ti)混合物時(shi),流體(ti)(ti)中的(de)(de)某一組(zu)分或(huo)某些(xie)組(zu)分可(ke)被吸(xi)表面并(bing)濃集其上,此現象稱為(wei)吸(xi)附(fu)(fu)(fu)。吸(xi)附(fu)(fu)(fu)處理廢氣時(shi),吸(xi)附(fu)(fu)(fu)的(de)(de)對象是氣態污染(ran)物,氣固吸(xi)附(fu)(fu)(fu)。被吸(xi)附(fu)(fu)(fu)的(de)(de)氣體(ti)(ti)組(zu)分稱為(wei)吸(xi)附(fu)(fu)(fu)質(zhi),多孔固體(ti)(ti)物質(zhi)稱為(wei)吸(xi)附(fu)(fu)(fu)劑(ji)。
固體(ti)表面(mian)(mian)(mian)吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)了吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)質(zhi)后,一部被吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)的吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)質(zhi)可(ke)從吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)劑(ji)(ji)(ji)表面(mian)(mian)(mian)脫離(li),此(ci)現附(fu)(fu)(fu)(fu)(fu)。而當吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)進行(xing)一段時(shi)間后,由于表面(mian)(mian)(mian)吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)質(zhi)的濃(nong)集(ji),使其吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)能力明(ming)顯(xian)下(xia)降而吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)凈化的要(yao)求,此(ci)時(shi)需(xu)要(yao)采用一定(ding)的措施使吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)劑(ji)(ji)(ji)上已吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)的吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)質(zhi)脫附(fu)(fu)(fu)(fu)(fu),以協的吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)能力,這個過(guo)程稱為(wei)吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)劑(ji)(ji)(ji)的再(zai)生。因此(ci)在實際吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)工程中,正是利用吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)一再(zai)生一再(zai)吸(xi)(xi)(xi)(xi)(xi)附(fu)(fu)(fu)(fu)(fu)的循(xun)環過(guo)程,達到除去廢氣(qi)中污染物質(zhi)并回收廢氣(qi)中有(you)用組分(fen)。