洗滌塔是一種新(xin)型的(de)氣(qi)(qi)體(ti)凈(jing)化處(chu)理設備。它(ta)是在可浮動(dong)填料層氣(qi)(qi)體(ti)凈(jing)化器的(de)基礎上改進而產生的(de),廣泛(fan)應用于(yu)工業廢氣(qi)(qi)凈(jing)化、除塵(chen)等方面的(de)前處(chu)理,凈(jing)化效果很好。對煤氣(qi)(qi)化工藝來說(shuo),煤氣(qi)(qi)洗滌不可避免(mian),無論什么(me)煤氣(qi)(qi)化技術都用到這一單元操(cao)作。由于(yu)其工作原理類(lei)似(si)洗滌過(guo)程,故名洗滌塔。
洗(xi)(xi)(xi)滌(di)(di)塔(ta)與精(jing)餾塔(ta)類似(si),由(you)塔(ta)體(ti),塔(ta)板(ban)(ban),再沸器,冷凝(ning)(ning)器組(zu)成。由(you)于(yu)(yu)洗(xi)(xi)(xi)滌(di)(di)塔(ta)是進(jin)行粗分(fen)(fen)(fen)(fen)(fen)離的設(she)備(bei),所以(yi)(yi)塔(ta)板(ban)(ban)數(shu)量(liang)一(yi)般(ban)較(jiao)少,通(tong)常不會(hui)超過(guo)十(shi)級(ji)。 洗(xi)(xi)(xi)滌(di)(di)塔(ta)適用于(yu)(yu)含有少量(liang)粉塵的混(hun)合(he)(he)氣體(ti)分(fen)(fen)(fen)(fen)(fen)離,各(ge)組(zu)分(fen)(fen)(fen)(fen)(fen)不會(hui)發生(sheng)(sheng)反應(ying),且產物應(ying)容易液(ye)(ye)化,粉塵等雜質(zhi)(也(ye)可以(yi)(yi)稱之為高沸物)不易液(ye)(ye)化或凝(ning)(ning)固(gu)。當混(hun)合(he)(he)氣從洗(xi)(xi)(xi)滌(di)(di)塔(ta)中部(bu)通(tong)入洗(xi)(xi)(xi)滌(di)(di)塔(ta),由(you)于(yu)(yu)塔(ta)板(ban)(ban)間存(cun)在產物組(zu)分(fen)(fen)(fen)(fen)(fen)液(ye)(ye)體(ti),產物組(zu)分(fen)(fen)(fen)(fen)(fen)氣體(ti)液(ye)(ye)化的同時蒸發部(bu)分(fen)(fen)(fen)(fen)(fen),而雜質(zhi)由(you)于(yu)(yu)不能被(bei)液(ye)(ye)化或凝(ning)(ning)固(gu),當通(tong)過(guo)有液(ye)(ye)體(ti)存(cun)在的塔(ta)板(ban)(ban)時將(jiang)會(hui)被(bei)產物組(zu)分(fen)(fen)(fen)(fen)(fen)液(ye)(ye)體(ti)固(gu)定下來,產生(sheng)(sheng)洗(xi)(xi)(xi)滌(di)(di)作用,洗(xi)(xi)(xi)滌(di)(di)塔(ta)就(jiu)是根據(ju)這一(yi)原(yuan)理設(she)計(ji)和制(zhi)造的。
洗(xi)滌塔由塔體、塔板、再沸器和(he)冷(leng)凝器組成。在使用(yong)過(guo)程中再沸器一般(ban)
用(yong)(yong)(yong)(yong)(yong)蒸(zheng)(zheng)汽加熱,冷凝(ning)(ning)器(qi)用(yong)(yong)(yong)(yong)(yong)循環水導熱。在(zai)使(shi)(shi)用(yong)(yong)(yong)(yong)(yong)前(qian)應(ying)(ying)建立平(ping)衡(heng),即通(tong)(tong)入(ru)較純的(de)產(chan)物(wu)組分用(yong)(yong)(yong)(yong)(yong)蒸(zheng)(zheng)汽和冷凝(ning)(ning)水調節(jie)(jie)(jie)其(qi)蒸(zheng)(zheng)發(fa)量(liang)和回流(liu)量(liang),使(shi)(shi)其(qi)能(neng)(neng)(neng)(neng)在(zai)塔(ta)(ta)板(ban)上(shang)積累一定厚(hou)度液(ye)(ye)(ye)體,當混(hun)(hun)合(he)氣體組分通(tong)(tong)入(ru)時(shi)就能(neng)(neng)(neng)(neng)迅(xun)速起(qi)到(dao)洗(xi)(xi)滌(di)(di)(di)(di)作用(yong)(yong)(yong)(yong)(yong)。在(zai)使(shi)(shi)用(yong)(yong)(yong)(yong)(yong)過程中要控(kong)制(zhi)好一個(ge)液(ye)(ye)(ye)位,兩(liang)個(ge)溫(wen)度和兩(liang)個(ge)壓差等幾(ji)個(ge)要點。即洗(xi)(xi)滌(di)(di)(di)(di)塔(ta)(ta)液(ye)(ye)(ye)位,氣體進(jin)口溫(wen)度,塔(ta)(ta)頂溫(wen)度,塔(ta)(ta)間(jian)壓差(洗(xi)(xi)滌(di)(di)(di)(di)塔(ta)(ta)進(jin)口壓力(li)與(yu)塔(ta)(ta)頂壓力(li)之差),冷凝(ning)(ning)器(qi)壓差(塔(ta)(ta)頂與(yu)冷凝(ning)(ning)器(qi)出(chu)口壓力(li)之差)。一般來(lai)說(shuo),氣體進(jin)口溫(wen)度越高越好,可以(yi)防(fang)(fang)(fang)止(zhi)雜質凝(ning)(ning)固或液(ye)(ye)(ye)化(hua)不(bu)能(neng)(neng)(neng)(neng)進(jin)入(ru)洗(xi)(xi)滌(di)(di)(di)(di)塔(ta)(ta),但是(shi)也(ye)(ye)不(bu)能(neng)(neng)(neng)(neng)太高,以(yi)防(fang)(fang)(fang)系統因溫(wen)度過高而不(bu)易(yi)控(kong)制(zhi)。控(kong)制(zhi)溫(wen)度的(de)同時(shi)還需(xu)保證氣體流(liu)速,即進(jin)口的(de)壓力(li)不(bu)能(neng)(neng)(neng)(neng)太小,以(yi)便粉(fen)塵能(neng)(neng)(neng)(neng)進(jin)入(ru)洗(xi)(xi)滌(di)(di)(di)(di)塔(ta)(ta)。混(hun)(hun)合(he)氣體通(tong)(tong)入(ru)洗(xi)(xi)滌(di)(di)(di)(di)塔(ta)(ta)后,部分氣體會冷凝(ning)(ning)成液(ye)(ye)(ye)體而留在(zai)塔(ta)(ta)釜(fu)(fu),調節(jie)(jie)(jie)再(zai)(zai)沸器(qi)的(de)溫(wen)度使(shi)(shi)液(ye)(ye)(ye)體向(xiang)上(shang)蒸(zheng)(zheng)發(fa),再(zai)(zai)調節(jie)(jie)(jie)冷凝(ning)(ning)器(qi)使(shi)(shi)液(ye)(ye)(ye)體回流(liu)至塔(ta)(ta)板(ban),形(xing)成一個(ge)平(ping)衡(heng)。由于塔(ta)(ta)板(ban)上(shang)有(you)一定厚(hou)度液(ye)(ye)(ye)體,所(suo)以(yi)洗(xi)(xi)滌(di)(di)(di)(di)塔(ta)(ta)塔(ta)(ta)間(jian)會有(you)一定壓差,調節(jie)(jie)(jie)再(zai)(zai)沸器(qi)和冷凝(ning)(ning)器(qi)時(shi)應(ying)(ying)盡量(liang)使(shi)(shi)壓差保持(chi)恒定才(cai)能(neng)(neng)(neng)(neng)形(xing)成一個(ge)平(ping)衡(heng)。調節(jie)(jie)(jie)塔(ta)(ta)頂溫(wen)度時(shi)應(ying)(ying)防(fang)(fang)(fang)止(zhi)溫(wen)度過高而使(shi)(shi)雜質汽化(hua)或升華為氣體而不(bu)能(neng)(neng)(neng)(neng)起(qi)洗(xi)(xi)滌(di)(di)(di)(di)作用(yong)(yong)(yong)(yong)(yong),但冷凝(ning)(ning)溫(wen)度也(ye)(ye)不(bu)宜過低,防(fang)(fang)(fang)止(zhi)產(chan)物(wu)液(ye)(ye)(ye)體在(zai)冷凝(ning)(ning)器(qi)積液(ye)(ye)(ye)影(ying)響使(shi)(shi)用(yong)(yong)(yong)(yong)(yong)。在(zai)注意(yi)以(yi)上(shang)要點的(de)同時(shi)還需(xu)注意(yi)用(yong)(yong)(yong)(yong)(yong)再(zai)(zai)沸器(qi)調節(jie)(jie)(jie)洗(xi)(xi)滌(di)(di)(di)(di)塔(ta)(ta)的(de)液(ye)(ye)(ye)位,為防(fang)(fang)(fang)止(zhi)塔(ta)(ta)釜(fu)(fu)液(ye)(ye)(ye)中雜質濃度過高產(chan)生(sheng)沉淀,應(ying)(ying)使(shi)(shi)其(qi)緩(huan)慢上(shang)漲(zhang)。
1、由于高沸(fei)物在(zai)(zai)(zai)洗滌過(guo)程(cheng)中(zhong)被固定在(zai)(zai)(zai)洗滌塔(ta)(ta)塔(ta)(ta)釜(fu)中(zhong),所以使用一段時間后塔(ta)(ta)釜(fu)液的(de)高沸(fei)物含量會升高,所以在(zai)(zai)(zai)使用一定時間后要對洗滌塔(ta)(ta)塔(ta)(ta)釜(fu)液進行置(zhi)換,防(fang)止高沸(fei)物在(zai)(zai)(zai)塔(ta)(ta)釜(fu)沉積。
2、由于洗滌(di)塔塔釜液(ye)中含有高(gao)沸物,容(rong)易堵(du)塞(sai)液(ye)位(wei)計(ji),所以一般采用部分回(hui)流液(ye)沖洗液(ye)位(wei)計(ji)的(de)方式(shi)防止液(ye)位(wei)計(ji)堵(du)塞(sai)。
煤氣化技術(shu)都用到這一單(dan)元操作。