過濾(lv)式(shi)除(chu)(chu)(chu)塵(chen)(chen)器是使含塵(chen)(chen)氣(qi)體通過一定的(de)過濾(lv)材料來達到分(fen)離氣(qi)體中固(gu)體粉塵(chen)(chen)的(de)一種(zhong)高效除(chu)(chu)(chu)塵(chen)(chen)設備。過濾(lv)式(shi)除(chu)(chu)(chu)塵(chen)(chen)器主要(yao)有兩類。一類是利用纖維編織物作為過濾(lv)介(jie)質(zhi)的(de)袋式(shi)除(chu)(chu)(chu)塵(chen)(chen)器;另(ling)一類是采用砂、礫、焦炭等顆(ke)粒物作為過濾(lv)介(jie)質(zhi)的(de)顆(ke)粒層(ceng)除(chu)(chu)(chu)塵(chen)(chen)器。
袋式除(chu)塵器工作原理
袋式除(chu)塵(chen)器是(shi)將棉、毛或人造纖維等材料(liao)加工成織物(wu)作(zuo)為濾(lv)(lv)料(liao),制成濾(lv)(lv)袋對含塵(chen)氣體進行過濾(lv)(lv)。當含塵(chen)氣流通過濾(lv)(lv)料(liao)孔隙時粉塵(chen)被阻留下(xia)來,清潔氣流穿過濾(lv)(lv)袋之(zhi)后排出。沉積在濾(lv)(lv)袋上的粉塵(chen)通過機械振動,從(cong)濾(lv)(lv)料(liao)表面脫(tuo)落至灰斗(dou)中。
濾(lv)(lv)(lv)料本(ben)身的(de)(de)網孔(kong)較(jiao)大(da),一(yi)般(ban)為(wei)(wei)(wei)20~50μm,表(biao)面(mian)起絨的(de)(de)濾(lv)(lv)(lv)料為(wei)(wei)(wei)5~10μm。因此,新(xin)用(yong)濾(lv)(lv)(lv)袋(dai)的(de)(de)除(chu)(chu)(chu)塵(chen)(chen)(chen)效(xiao)(xiao)率較(jiao)低(di)。粉塵(chen)(chen)(chen)顆粒因篩濾(lv)(lv)(lv)、慣性碰撞、攔截、擴(kuo)散、靜(jing)電和重力(li)沉降(jiang)等作用(yong),使(shi)(shi)得(de)粗塵(chen)(chen)(chen)粒首先被阻(zu)(zu)留,并在網孔(kong)之間產(chan)生 “架橋”現(xian)象(xiang),很快在濾(lv)(lv)(lv)布(bu)(bu)表(biao)面(mian)形(xing)(xing)(xing)成(cheng)一(yi)層(ceng)所謂粉塵(chen)(chen)(chen)初(chu)(chu)層(ceng)。初(chu)(chu)層(ceng)形(xing)(xing)(xing)成(cheng)后,它便(bian)成(cheng)了濾(lv)(lv)(lv)袋(dai)的(de)(de)主(zhu)(zhu)要過(guo)(guo)(guo)(guo)濾(lv)(lv)(lv)層(ceng),而濾(lv)(lv)(lv)布(bu)(bu)只不(bu)過(guo)(guo)(guo)(guo)起著形(xing)(xing)(xing)成(cheng)顆粒初(chu)(chu)層(ceng)和支撐它的(de)(de)骨架作用(yong)。粉塵(chen)(chen)(chen)初(chu)(chu)層(ceng)形(xing)(xing)(xing)成(cheng)之后,使(shi)(shi)濾(lv)(lv)(lv)布(bu)(bu)成(cheng)為(wei)(wei)(wei)對粗、細粉塵(chen)(chen)(chen)皆有效(xiao)(xiao)的(de)(de)過(guo)(guo)(guo)(guo)濾(lv)(lv)(lv)材料,過(guo)(guo)(guo)(guo)濾(lv)(lv)(lv)效(xiao)(xiao)率劇(ju)增。對于1μm以(yi)(yi)上的(de)(de)塵(chen)(chen)(chen)粒,主(zhu)(zhu)要靠慣性碰撞,對于1μm以(yi)(yi)下(xia)的(de)(de)塵(chen)(chen)(chen)粒,主(zhu)(zhu)要靠擴(kuo)散,總的(de)(de)過(guo)(guo)(guo)(guo)濾(lv)(lv)(lv)效(xiao)(xiao)率可達99%以(yi)(yi)上。隨著粉塵(chen)(chen)(chen)在濾(lv)(lv)(lv)袋(dai)上的(de)(de)積聚,除(chu)(chu)(chu)塵(chen)(chen)(chen)效(xiao)(xiao)率不(bu)斷增加,同時(shi)阻(zu)(zu)力(li)也相(xiang)應增大(da)。當阻(zu)(zu)力(li)達到一(yi)定(ding)程度時(shi),濾(lv)(lv)(lv)袋(dai)兩側的(de)(de)壓(ya)力(li)差會(hui)把有些已附著在濾(lv)(lv)(lv)料上的(de)(de)細小粉塵(chen)(chen)(chen)擠(ji)壓(ya)過(guo)(guo)(guo)(guo)去,使(shi)(shi)除(chu)(chu)(chu)塵(chen)(chen)(chen)效(xiao)(xiao)率明顯(xian)(xian)(xian)下(xia)降(jiang),同時(shi)除(chu)(chu)(chu)塵(chen)(chen)(chen)器阻(zu)(zu)力(li)過(guo)(guo)(guo)(guo)大(da)會(hui)使(shi)(shi)除(chu)(chu)(chu)塵(chen)(chen)(chen)系(xi)統(tong)(tong)的(de)(de)處理氣(qi)體量(liang)顯(xian)(xian)(xian)著下(xia)降(jiang),影響生產(chan)系(xi)統(tong)(tong)的(de)(de)排風(feng)效(xiao)(xiao)果。因此,除(chu)(chu)(chu)塵(chen)(chen)(chen)器阻(zu)(zu)力(li)達到一(yi)定(ding)數值后,要及時(shi)進(jin)行清灰,而清灰時(shi)又(you)不(bu)能破壞粉塵(chen)(chen)(chen)初(chu)(chu)層(ceng),否則會(hui)引起除(chu)(chu)(chu)塵(chen)(chen)(chen)效(xiao)(xiao)率顯(xian)(xian)(xian)著降(jiang)低(di)。