過(guo)(guo)濾(lv)式除(chu)(chu)塵(chen)器(qi)是使含塵(chen)氣(qi)體(ti)通過(guo)(guo)一定的過(guo)(guo)濾(lv)材料來達到(dao)分離氣(qi)體(ti)中固(gu)體(ti)粉塵(chen)的一種高(gao)效除(chu)(chu)塵(chen)設備。過(guo)(guo)濾(lv)式除(chu)(chu)塵(chen)器(qi)主要有兩類(lei)。一類(lei)是利用(yong)纖(xian)維編(bian)織物作為過(guo)(guo)濾(lv)介(jie)質(zhi)的袋式除(chu)(chu)塵(chen)器(qi);另一類(lei)是采用(yong)砂、礫(li)、焦炭(tan)等顆粒物作為過(guo)(guo)濾(lv)介(jie)質(zhi)的顆粒層(ceng)除(chu)(chu)塵(chen)器(qi)。
袋式除塵器工(gong)作原理(li)
袋(dai)式除塵(chen)器是(shi)將棉、毛或人(ren)造纖(xian)維等材料(liao)加(jia)工成織物作為濾(lv)料(liao),制(zhi)成濾(lv)袋(dai)對含(han)塵(chen)氣體進行(xing)過(guo)(guo)濾(lv)。當含(han)塵(chen)氣流(liu)通(tong)(tong)過(guo)(guo)濾(lv)料(liao)孔(kong)隙時粉(fen)塵(chen)被阻留下(xia)來,清潔氣流(liu)穿過(guo)(guo)濾(lv)袋(dai)之后排出。沉積在濾(lv)袋(dai)上的粉(fen)塵(chen)通(tong)(tong)過(guo)(guo)機(ji)械振動,從濾(lv)料(liao)表面脫(tuo)落(luo)至灰斗中(zhong)。
濾(lv)(lv)(lv)(lv)料(liao)本身的網(wang)孔較大,一般(ban)為(wei)20~50μm,表面(mian)起絨(rong)的濾(lv)(lv)(lv)(lv)料(liao)為(wei)5~10μm。因此,新用濾(lv)(lv)(lv)(lv)袋(dai)(dai)的除(chu)塵(chen)(chen)(chen)效(xiao)率較低(di)。粉(fen)(fen)塵(chen)(chen)(chen)顆(ke)粒因篩濾(lv)(lv)(lv)(lv)、慣性碰撞、攔截、擴散、靜電(dian)和重力(li)沉降等作(zuo)用,使得(de)粗塵(chen)(chen)(chen)粒首先被阻(zu)留,并在(zai)(zai)網(wang)孔之(zhi)間產生(sheng)(sheng) “架橋(qiao)”現象,很(hen)快(kuai)在(zai)(zai)濾(lv)(lv)(lv)(lv)布(bu)表面(mian)形成(cheng)(cheng)(cheng)一層(ceng)(ceng)所謂粉(fen)(fen)塵(chen)(chen)(chen)初層(ceng)(ceng)。初層(ceng)(ceng)形成(cheng)(cheng)(cheng)后,它(ta)(ta)便成(cheng)(cheng)(cheng)了濾(lv)(lv)(lv)(lv)袋(dai)(dai)的主(zhu)要(yao)過(guo)(guo)濾(lv)(lv)(lv)(lv)層(ceng)(ceng),而(er)濾(lv)(lv)(lv)(lv)布(bu)只不(bu)過(guo)(guo)起著(zhu)形成(cheng)(cheng)(cheng)顆(ke)粒初層(ceng)(ceng)和支撐它(ta)(ta)的骨(gu)架作(zuo)用。粉(fen)(fen)塵(chen)(chen)(chen)初層(ceng)(ceng)形成(cheng)(cheng)(cheng)之(zhi)后,使濾(lv)(lv)(lv)(lv)布(bu)成(cheng)(cheng)(cheng)為(wei)對粗、細(xi)粉(fen)(fen)塵(chen)(chen)(chen)皆有(you)效(xiao)的過(guo)(guo)濾(lv)(lv)(lv)(lv)材(cai)料(liao),過(guo)(guo)濾(lv)(lv)(lv)(lv)效(xiao)率劇增(zeng)。對于(yu)1μm以(yi)(yi)(yi)上(shang)的塵(chen)(chen)(chen)粒,主(zhu)要(yao)靠慣性碰撞,對于(yu)1μm以(yi)(yi)(yi)下(xia)的塵(chen)(chen)(chen)粒,主(zhu)要(yao)靠擴散,總的過(guo)(guo)濾(lv)(lv)(lv)(lv)效(xiao)率可達(da)99%以(yi)(yi)(yi)上(shang)。隨著(zhu)粉(fen)(fen)塵(chen)(chen)(chen)在(zai)(zai)濾(lv)(lv)(lv)(lv)袋(dai)(dai)上(shang)的積聚(ju),除(chu)塵(chen)(chen)(chen)效(xiao)率不(bu)斷(duan)增(zeng)加,同時(shi)(shi)阻(zu)力(li)也相(xiang)應(ying)增(zeng)大。當阻(zu)力(li)達(da)到(dao)一定程度時(shi)(shi),濾(lv)(lv)(lv)(lv)袋(dai)(dai)兩(liang)側的壓力(li)差(cha)會(hui)把有(you)些已附著(zhu)在(zai)(zai)濾(lv)(lv)(lv)(lv)料(liao)上(shang)的細(xi)小粉(fen)(fen)塵(chen)(chen)(chen)擠壓過(guo)(guo)去,使除(chu)塵(chen)(chen)(chen)效(xiao)率明(ming)顯(xian)下(xia)降,同時(shi)(shi)除(chu)塵(chen)(chen)(chen)器(qi)阻(zu)力(li)過(guo)(guo)大會(hui)使除(chu)塵(chen)(chen)(chen)系統的處理氣(qi)體量顯(xian)著(zhu)下(xia)降,影響(xiang)生(sheng)(sheng)產系統的排風效(xiao)果。因此,除(chu)塵(chen)(chen)(chen)器(qi)阻(zu)力(li)達(da)到(dao)一定數值后,要(yao)及(ji)時(shi)(shi)進行清灰,而(er)清灰時(shi)(shi)又(you)不(bu)能(neng)破壞粉(fen)(fen)塵(chen)(chen)(chen)初層(ceng)(ceng),否則(ze)會(hui)引起除(chu)塵(chen)(chen)(chen)效(xiao)率顯(xian)著(zhu)降低(di)。