前言
十二五期間(jian)，我(wo)國平均(jun)霧(wu)霾天數逐漸增多(duo)，空(kong)氣(qi)污(wu)染(ran)加(jia)劇，霧(wu)霾嚴重影響人們身體(ti)健康和正常(chang)工作(zuo)、生(sheng)活秩序。而霧(wu)霾天氣(qi)的(de)形成(cheng)與一次(ci)細顆(ke)物PM2.5的(de)排放(fang)(fang)(fang)(fang)及(ji)環境空(kong)氣(qi)中(zhong)的(de)二次(ci)細顆(ke)粒物的(de)形成(cheng)密切(qie)相關。我(wo)國的(de)能(neng)源消(xiao)費主要以煤炭(tan)為(wei)主，發電方(fang)式在(zai)很(hen)長的(de)一段時間(jian)內是以燃煤發電為(wei)主。《火電廠(chang)大(da)氣(qi)污(wu)染(ran)排放(fang)(fang)(fang)(fang)標準》（ GB 13223-2011） 要求在(zai)一般地(di)區(qu)煙塵(chen)排放(fang)(fang)(fang)(fang)限(xian)(xian)(xian)值30 mg /m3，重點地(di)區(qu)煙塵(chen)排放(fang)(fang)(fang)(fang)限(xian)(xian)(xian)值20 mg /m3。基(ji)于這樣的(de)原因，許多(duo)大(da)型電廠(chang)都安排了電袋(dai)復合除(chu)塵(chen)器，基(ji)本(ben)上達(da)到(dao)了排放(fang)(fang)(fang)(fang)要求。2014年(nian)9月12日，國家發改(gai)委、環境保護部(bu)、能(neng)源局聯合印發《煤電節能(neng)減排升(sheng)級與改(gai)造(zao)行(xing)動(dong)計劃（ 2014-2020）》的(de)通知中(zhong)，強調嚴控大(da)氣(qi)污(wu)染(ran)物排放(fang)(fang)(fang)(fang)，東部(bu)地(di)區(qu)11個省(sheng)市新建燃煤發電機(ji)(ji)(ji)組大(da)氣(qi)污(wu)染(ran)物排放(fang)(fang)(fang)(fang)濃度(du)基(ji)本(ben)達(da)到(dao)燃氣(qi)輪(lun)機(ji)(ji)(ji)組排放(fang)(fang)(fang)(fang)限(xian)(xian)(xian)值，在(zai)基(ji)準含(han)氧6%條(tiao)件(jian)下，煙塵(chen)、SO2、NOx排放(fang)(fang)(fang)(fang)濃度(du)分別(bie)不高于10、35、50 mg /m3，中(zhong)部(bu)地(di)區(qu)8 省(sheng)則要求接(jie)近或達(da)到(dao)燃氣(qi)輪(lun)機(ji)(ji)(ji)組排放(fang)(fang)(fang)(fang)限(xian)(xian)(xian)值，鼓勵西部(bu)地(di)區(qu)接(jie)近或達(da)到(dao)燃氣(qi)輪(lun)機(ji)(ji)(ji)組排放(fang)(fang)(fang)(fang)限(xian)(xian)(xian)值。
1.成熟的(de)除塵器技術
目前國內比較成熟且適(shi)用于各級容量機組的除塵(chen)(chen)技(ji)術主要是(shi)靜電除塵(chen)(chen)器和(he)袋式除塵(chen)(chen)器。
（1）靜(jing)電(dian)除(chu)(chu)(chu)塵(chen)(chen)(chen)器使用(yong)周(zhou)期長、維護費低且適用(yong)性較(jiao)廣泛，國內電(dian)除(chu)(chu)(chu)塵(chen)(chen)(chen)器出口(kou)煙塵(chen)(chen)(chen)濃度限制為(wei)20 mg /m3時，50%以上的(de)煤(mei)種(zhong)適用(yong)常(chang)規(gui)電(dian)除(chu)(chu)(chu)塵(chen)(chen)(chen)器； 但靜(jing)電(dian)除(chu)(chu)(chu)塵(chen)(chen)(chen)器耗電(dian)量大，設備(bei)復(fu)雜、占地(di)大并且對(dui)粉(fen)塵(chen)(chen)(chen)比(bi)電(dian)阻要求(qiu)較(jiao)高。對(dui)除(chu)(chu)(chu)塵(chen)(chen)(chen)效(xiao)率低于99.8%，通常(chang)選用(yong)電(dian)除(chu)(chu)(chu)塵(chen)(chen)(chen)器。像神府東勝煤(mei)、晉北煤(mei)等(deng)電(dian)除(chu)(chu)(chu)塵(chen)(chen)(chen)器適應性較(jiao)好的(de)煤(mei)種(zhong)，宜選用(yong)電(dian)除(chu)(chu)(chu)塵(chen)(chen)(chen)器。
（2）布(bu)袋式除(chu)塵(chen)器(qi)對(dui)粉(fen)塵(chen)氣流(liu)量(liang)的(de)變化(hua)適宜性(xing)強(qiang)，具(ju)有除(chu)塵(chen)效(xiao)率高(gao)，運行穩定，適用范圍廣，操作(zuo)維護容易(yi)并且可處(chu)理高(gao)溫、高(gao)比電(dian)阻的(de)粉(fen)塵(chen)，但布(bu)袋除(chu)塵(chen)壽(shou)命(ming)主要(yao)取決于濾袋的(de)使用壽(shou)命(ming)，不(bu)適宜于黏(nian)結性(xing)強(qiang)及吸濕性(xing)強(qiang)的(de)粉(fen)塵(chen)，特別是煙氣溫度不(bu)能低于露點溫度，否則會產(chan)生結露，致使濾袋堵塞。像準格爾煤、宣威煤、澳大利(li)亞(ya)煤等電(dian)除(chu)塵(chen)器(qi)適應性(xing)差的(de)煤種，不(bu)宜選用常(chang)規(gui)電(dian)除(chu)塵(chen)器(qi)，可選用布(bu)袋除(chu)塵(chen)器(qi)。
2.高效除塵技術方案(an)
2.1濕式電除塵(chen)器
濕式(shi)電(dian)除(chu)塵(chen)器(qi)是直接將(jiang)(jiang)水(shui)(shui)霧(wu)噴向(xiang)電(dian)極(ji)和電(dian)暈(yun)區，水(shui)(shui)霧(wu)在(zai)(zai)芒刺電(dian)極(ji)形成的(de)強大的(de)電(dian)暈(yun)場內(nei)荷電(dian)后分(fen)裂(lie)進一步霧(wu)化，在(zai)(zai)這(zhe)里(li)電(dian)場力(li)、荷電(dian)水(shui)(shui)霧(wu)的(de)碰撞攔截、吸附凝(ning)并，共同(tong)對粉(fen)(fen)塵(chen)粒子起捕(bu)集作(zuo)用，最終粉(fen)(fen)塵(chen)粒子在(zai)(zai)電(dian)場力(li)的(de)驅動下到達集塵(chen)極(ji)而被捕(bu)集；與(yu)干(gan)式(shi)電(dian)除(chu)塵(chen)器(qi)通過振(zhen)(zhen)打將(jiang)(jiang)極(ji)板上的(de)灰(hui)振(zhen)(zhen)落至灰(hui)斗不同(tong)的(de)是：濕式(shi)電(dian)除(chu)塵(chen)器(qi)則是將(jiang)(jiang)水(shui)(shui)噴至集塵(chen)極(ji)上形成連續的(de)水(shui)(shui)膜，采用水(shui)(shui)清灰(hui)，無振(zhen)(zhen)打裝置(zhi)，流動水(shui)(shui)膜將(jiang)(jiang)捕(bu)獲的(de)粉(fen)(fen)塵(chen)沖刷到灰(hui)斗中隨水(shui)(shui)排出。濕式(shi)電(dian)除(chu)塵(chen)器(qi)對酸霧(wu)、有毒重金屬以及PM10，尤其是PM2.5 的(de)細(xi)微粉(fen)(fen)塵(chen)有良(liang)好(hao)的(de)脫(tuo)除(chu)效(xiao)果。
2.2低低溫靜電除塵(chen)器(qi)技術
低(di)(di)（低(di)(di)）溫(wen)(wen)(wen)(wen)(wen)靜(jing)電(dian)(dian)除(chu)塵技術是指(zhi)當煙(yan)(yan)(yan)氣(qi)(qi)(qi)(qi)經過(guo)低(di)(di)溫(wen)(wen)(wen)(wen)(wen)省煤器時，煙(yan)(yan)(yan)氣(qi)(qi)(qi)(qi)溫(wen)(wen)(wen)(wen)(wen)度(du)降低(di)(di)，靜(jing)電(dian)(dian)除(chu)塵器入(ru)口煙(yan)(yan)(yan)氣(qi)(qi)(qi)(qi)溫(wen)(wen)(wen)(wen)(wen)度(du)運(yun)行在(zai)低(di)(di)于(yu)煙(yan)(yan)(yan)氣(qi)(qi)(qi)(qi)酸露點溫(wen)(wen)(wen)(wen)(wen)度(du)5 ℃～10 ℃。低(di)(di)（低(di)(di)）溫(wen)(wen)(wen)(wen)(wen)靜(jing)電(dian)(dian)除(chu)塵技術工(gong)作原理：煙(yan)(yan)(yan)溫(wen)(wen)(wen)(wen)(wen)降低(di)(di)，使(shi)得粉塵比電(dian)(dian)阻降低(di)(di)至(zhi)108Ω·cm～1011Ω·cm，粉塵的荷電(dian)(dian)性(xing)能(neng)提高；煙(yan)(yan)(yan)溫(wen)(wen)(wen)(wen)(wen)降低(di)(di)，煙(yan)(yan)(yan)氣(qi)(qi)(qi)(qi)量(liang)減(jian)少，電(dian)(dian)除(chu)塵器電(dian)(dian)場(chang)風(feng)速也得以降低(di)(di)；煙(yan)(yan)(yan)溫(wen)(wen)(wen)(wen)(wen)降低(di)(di)，煙(yan)(yan)(yan)氣(qi)(qi)(qi)(qi)中顆粒及氣(qi)(qi)(qi)(qi)體(ti)分(fen)子熱運(yun)動能(neng)力減(jian)弱，氣(qi)(qi)(qi)(qi)體(ti)擊(ji)穿電(dian)(dian)壓提高，粉塵趨近速度(du)提高；當除(chu)塵器入(ru)口煙(yan)(yan)(yan)氣(qi)(qi)(qi)(qi)溫(wen)(wen)(wen)(wen)(wen)度(du)已經降到(dao)露點溫(wen)(wen)(wen)(wen)(wen)度(du)以下，可去除(chu)絕大(da)部分(fen)SO3，減(jian)小尾(wei)部煙(yan)(yan)(yan)氣(qi)(qi)(qi)(qi)低(di)(di)溫(wen)(wen)(wen)(wen)(wen)腐(fu)蝕。低(di)(di)（低(di)(di)）溫(wen)(wen)(wen)(wen)(wen)靜(jing)電(dian)(dian)除(chu)塵技術在(zai)國外應用非常成熟，也普(pu)遍引起(qi)了國內(nei)業主的關注。
2.3靜電除(chu)塵(chen)器(qi)的旋轉電極技術
旋轉電(dian)(dian)極(ji)靜電(dian)(dian)除塵(chen)(chen)器(qi)(qi)(qi)的(de)(de)(de)收塵(chen)(chen)機(ji)理(li)與常規(gui)電(dian)(dian)除塵(chen)(chen)器(qi)(qi)(qi)完全相同，但為了使末電(dian)(dian)場極(ji)板始終保持(chi)干(gan)凈，防止(zhi)反電(dian)(dian)暈，防止(zhi)二次揚(yang)塵(chen)(chen)，以保障(zhang)除塵(chen)(chen)器(qi)(qi)(qi)效率，改(gai)傳統的(de)(de)(de)振打清灰為清灰刷，可清除高比(bi)電(dian)(dian)阻粉(fen)塵(chen)(chen)、粘性粉(fen)塵(chen)(chen)；清灰刷置(zhi)于非收塵(chen)(chen)區，最(zui)大(da)限(xian)度地減少二次揚(yang)塵(chen)(chen)，從而降(jiang)低能耗(hao)的(de)(de)(de)同時提高粉(fen)塵(chen)(chen)收集(ji)效率，滿足更高的(de)(de)(de)環保要求。經過多年的(de)(de)(de)運行(xing)經驗，日立公司(si)的(de)(de)(de)移動極(ji)板靜電(dian)(dian)除塵(chen)(chen)器(qi)(qi)(qi)技術已經比(bi)較成熟；國內的(de)(de)(de)浙江(jiang)菲達(da)環保科技股(gu)份有限(xian)公司(si)在河北衡豐發電(dian)(dian)廠(chang)二期(qi)300 MW機(ji)組和江(jiang)蘇徐塘發電(dian)(dian)廠(chang)5號爐300 MW機(ji)組有運行(xing)業績(ji)。
2.4增(zeng)加濕(shi)式(shi)電除(chu)塵技術
濕(shi)(shi)式電(dian)(dian)除(chu)(chu)(chu)(chu)塵(chen)(chen)(chen)器(qi)(qi)(qi)將水(shui)(shui)(shui)噴至極板上(shang)(shang)使粉(fen)塵(chen)(chen)(chen)沖刷(shua)到(dao)灰斗(dou)中(zhong)隨水(shui)(shui)(shui)排出(chu)，可(ke)(ke)以(yi)避免已捕集粉(fen)塵(chen)(chen)(chen)的(de)再(zai)飛揚，達到(dao)很(hen)高(gao)(gao)的(de)除(chu)(chu)(chu)(chu)塵(chen)(chen)(chen)效(xiao)率(lv)，同時(shi)還可(ke)(ke)以(yi)消除(chu)(chu)(chu)(chu)“石膏雨(yu)”現(xian)象。國外該技(ji)(ji)術已很(hen)很(hen)熟，從美國和日本電(dian)(dian)廠(chang)(chang)的(de)運(yun)行情況(kuang)來看，濕(shi)(shi)式除(chu)(chu)(chu)(chu)塵(chen)(chen)(chen)器(qi)(qi)(qi)能(neng)夠(gou)長期(qi)穩定地(di)除(chu)(chu)(chu)(chu)去(qu)煙塵(chen)(chen)(chen)，并且煙氣濃(nong)度(du)(du)可(ke)(ke)以(yi)控(kong)制在(zai)(zai)10 mg /m3 以(yi)下，去(qu)除(chu)(chu)(chu)(chu)率(lv)在(zai)(zai)70%以(yi)上(shang)(shang)，對汞控(kong)制效(xiao)果也很(hen)好(hao)。但初(chu)始投(tou)入(ru)成本較(jiao)高(gao)(gao)、耗水(shui)(shui)(shui)量大、污(wu)水(shui)(shui)(shui)需要處理、在(zai)(zai)高(gao)(gao)粉(fen)塵(chen)(chen)(chen)濃(nong)度(du)(du)或高(gao)(gao)NOx濃(nong)度(du)(du)的(de)煙氣條件下，不宜(yi)采(cai)用(yong)濕(shi)(shi)式電(dian)(dian)除(chu)(chu)(chu)(chu)塵(chen)(chen)(chen)器(qi)(qi)(qi)。日立濕(shi)(shi)式靜電(dian)(dian)除(chu)(chu)(chu)(chu)塵(chen)(chen)(chen)器(qi)(qi)(qi)2001 年應(ying)用(yong)于(yu)中(zhong)部電(dian)(dian)力的(de)碧(bi)南電(dian)(dian)廠(chang)(chang)4、5 號1 000 MW 機(ji)組。運(yun)行狀況(kuang)良好(hao)，常年維持在(zai)(zai)2 ～ 5 mg /m3，煤(mei)質較(jiao)好(hao)情況(kuang)最低達到(dao)1 mg /m3。國內南京國電(dian)(dian)山(shan)大能(neng)源公司(si)研發的(de)濕(shi)(shi)式靜電(dian)(dian)除(chu)(chu)(chu)(chu)塵(chen)(chen)(chen)器(qi)(qi)(qi)技(ji)(ji)術，于(yu)2012 年8 月在(zai)(zai)國電(dian)(dian)益陽電(dian)(dian)廠(chang)(chang)300 MW 機(ji)組上(shang)(shang)進行應(ying)用(yong)，效(xiao)果良好(hao)。浙江六橫電(dian)(dian)廠(chang)(chang)、國華舟山(shan)電(dian)(dian)廠(chang)(chang)投(tou)運(yun)的(de)濕(shi)(shi)式靜電(dian)(dian)除(chu)(chu)(chu)(chu)塵(chen)(chen)(chen)器(qi)(qi)(qi)，測得(de)出(chu)口煙塵(chen)(chen)(chen)濃(nong)度(du)(du)也都低于(yu)5 mg /m3。
2.5改(gai)工頻(pin)(pin)為(wei)高頻(pin)(pin)電源(yuan)
高頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)是一(yi)種利用高頻(pin)(pin)開關技術(shu)而形成(cheng)的(de)逆變(bian)式電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)，其供(gong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)由一(yi)系列窄(zhai)脈沖構(gou)成(cheng)。高頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)采(cai)用三相平(ping)衡電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)，對電(dian)(dian)(dian)網(wang)影響小，無缺(que)相損耗，比(bi)工(gong)頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)對復雜多變(bian)的(de)煙氣(qi)工(gong)況具(ju)有更(geng)強的(de)適應(ying)性。就南京某電(dian)(dian)(dian)廠(chang)1 號(hao)爐1 臺電(dian)(dian)(dian)除(chu)塵器(qi)配(pei)(pei)備(bei)工(gong)頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)、2 號(hao)爐1 臺除(chu)塵器(qi)配(pei)(pei)備(bei)高頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)。該(gai)電(dian)(dian)(dian)廠(chang)2 號(hao)爐配(pei)(pei)套的(de)高頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)與1 號(hao)爐配(pei)(pei)套的(de)工(gong)頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)相比(bi)較，高頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)安(an)裝更(geng)方(fang)便、操作更(geng)簡單，可(ke)降低煙塵排放(fang)40% ～ 60%，相比(bi)工(gong)頻(pin)(pin)電(dian)(dian)(dian)源(yuan)(yuan)(yuan)(yuan)(yuan)(yuan)可(ke)節約電(dian)(dian)(dian)耗40% ～ 80%。配(pei)(pei)合電(dian)(dian)(dian)除(chu)塵器(qi)，除(chu)塵效率能(neng)達到99.80% ～ 99.85%。
結語
在當(dang)前的污染物排(pai)(pai)放(fang)(fang)控(kong)制形(xing)勢下，選(xuan)擇適合(he)(he)火電(dian)廠的排(pai)(pai)放(fang)(fang)限值乃至具體的技術路和除塵設備選(xuan)型至關重要。，需要在生產過程中(zhong)仔細研究(jiu)，根據環保排(pai)(pai)放(fang)(fang)要求和燃煤(mei)特性及(ji)煙氣參數等諸多方(fang)面綜合(he)(he)分析(xi)，選(xuan)擇合(he)(he)理的煙塵控(kong)制工藝技術，滿足達標排(pai)(pai)放(fang)(fang)的要求。