洗滌(di)塔是酸堿廢氣處理常用(yong)的設(she)備(bei)之一,適用(yong)于(yu)(yu)有機廢氣的預處理,應用(yong)于(yu)(yu)化工,電(dian)子(zi)、電(dian)鍍、制(zhi)藥、印刷、實(shi)驗室等行業。
洗滌塔的(de)工作(zuo)原理(以酸性(xing)氣體(ti)為例):
廢氣(qi)(qi)(qi)氣(qi)(qi)(qi)體(ti)(ti)從塔體(ti)(ti)下(xia)(xia)方進(jin)氣(qi)(qi)(qi)口進(jin)入洗(xi)滌塔,在(zai)通(tong)(tong)風機的(de)動力作用下(xia)(xia),迅(xun)速充滿進(jin)氣(qi)(qi)(qi)段(duan)(duan)空間,然(ran)后(hou)均勻地通(tong)(tong)過(guo)均流段(duan)(duan)上(shang)升到第(di)(di)1級(ji)填料吸收(shou)(shou)(shou)段(duan)(duan)。在(zai)填料的(de)表(biao)面上(shang),氣(qi)(qi)(qi)相中酸性(xing)物質與液(ye)相中堿性(xing)物質發生化學反(fan)應(ying)。反(fan)應(ying)生成物油(多數(shu)(shu)為可溶性(xing)鹽類)隨(sui)吸收(shou)(shou)(shou)液(ye)流入下(xia)(xia)部貯(zhu)液(ye)槽(cao)。未完全(quan)吸收(shou)(shou)(shou)的(de)廢氣(qi)(qi)(qi)氣(qi)(qi)(qi)體(ti)(ti)繼續上(shang)升進(jin)入第(di)(di)1級(ji)噴(pen)(pen)淋段(duan)(duan)。在(zai)噴(pen)(pen)淋段(duan)(duan)中吸收(shou)(shou)(shou)液(ye)從均布的(de)噴(pen)(pen)嘴高(gao)速噴(pen)(pen)出,形成無數(shu)(shu)細小霧滴(di)與氣(qi)(qi)(qi)體(ti)(ti)充分(fen)混合、接觸、繼續發生化學反(fan)應(ying)。然(ran)后(hou)酸性(xing)氣(qi)(qi)(qi)體(ti)(ti)上(shang)升到第(di)(di)二(er)級(ji)填料段(duan)(duan)、噴(pen)(pen)淋段(duan)(duan)進(jin)行(xing)與第(di)(di)1級(ji)類似的(de)吸收(shou)(shou)(shou)過(guo)程(cheng)。第(di)(di)二(er)級(ji)與第(di)(di)1級(ji)噴(pen)(pen)嘴密度(du)(du)不同(tong)(tong),噴(pen)(pen)液(ye)壓力不同(tong)(tong),吸收(shou)(shou)(shou)酸性(xing)氣(qi)(qi)(qi)體(ti)(ti)濃(nong)度(du)(du)范圍也有所不同(tong)(tong)。在(zai)噴(pen)(pen)淋段(duan)(duan)及(ji)填料段(duan)(duan)兩相接觸的(de)過(guo)程(cheng)也是材熱與傳(chuan)質的(de)過(guo)程(cheng)。
通過(guo)控制廢氣(qi)(qi)(qi)洗滌塔(ta)流速(su)與滯貯時間保證這(zhe)一過(guo)程的(de)充分與穩(wen)定(ding)。對于某(mou)些化學活潑(po)性(xing)較差(cha)的(de)酸性(xing)氣(qi)(qi)(qi)體(ti)(ti),尚需(xu)在吸收液(ye)中加入(ru)(ru)一定(ding)量的(de)表面(mian)活性(xing)劑。塔(ta)體(ti)(ti)的(de)上(shang)部是除霧(wu)段(duan),氣(qi)(qi)(qi)體(ti)(ti)中所夾帶的(de)吸收液(ye)霧(wu)滴在這(zhe)里被清除下來(lai),經過(guo)處理后的(de)潔(jie)凈空氣(qi)(qi)(qi)從廢氣(qi)(qi)(qi)吸收塔(ta)上(shang)端排氣(qi)(qi)(qi)管放入(ru)(ru)大氣(qi)(qi)(qi)。