浙江大學(xué)學(xué)報(bào)(理學(xué)版第37卷第4期Journal of Zhejiang University( Science Edit37No,42010年7月http://www.journalszju.educn/sciayDOI:10.3785/j,issn.1008-9497.2010.04.022污泥水煤漿的燃燒固硫試驗(yàn)研究胡勤海,朱建航,王丹,孟媛媛,武麗麗,羅彥章(浙江大學(xué)環(huán)境與資源學(xué)院,浙江杭州310029)摘要:在管式固定床上進(jìn)行了污泥水煤漿的燃燒試驗(yàn),著重研究了燃燒溫度、Ca/S摩爾比和固硫劑種類等因素對(duì)污泥水煤漿燃燒固硫的影吻,結(jié)果表明:隨著燃燒溫度的上升,污泥水煤漿的固硫車先升高后降低,在850℃時(shí)污泥水煤漿的圃硫率明顯高于其他燃燒溫度條件下的國(guó)硫率.隨著Ca/S摩爾比的增加,污泥水煤漿的國(guó)硫率呈明顯的上升趨勢(shì),但是Ca/S摩爾比從1.5增加到2.0時(shí),其固硫率上升趨于平蝮,綜合考慮經(jīng)濟(jì)性因素,污泥水煤漿燃燒國(guó)硫的優(yōu)化鈣硫摩爾比應(yīng)為1.5.污泥水煤漿燃燒時(shí)SOh析出規(guī)律與Ca(OH)2的分解規(guī)律相對(duì)比較一致,因此,Ca(OH)2的固硫效果優(yōu)于CaCO3.試驗(yàn)為污泥水煤漿的工業(yè)化應(yīng)用提供了理論基礎(chǔ),關(guān)鑣詞:污泥;水煤漿;固硫;燃燒中圖分類號(hào):X705文賦標(biāo)志碼:A文章編號(hào):10089497(2010)04-46704HU Qinhai, ZHU JianhANG Dan, MENG Yuan-yuan, WU Li-li, LUO Yan-zhang(School of environmental and Resource, Zhejiang University, Hangzhou 310029, China)Experimental study on combustion desulfurization of sludge coal water slurry. Journal of Zhejiang University( ScienceEdition),2010,37(4):467—470Abstract: Tests of combustion of sludge coal water slurry(S-CWS)were conducted in a fixed bed oven. Effects ofcombustion temperature, Ca/S molar ratio and desulfurizer kinds on desulfurization rate were investigated. Resultsshowed that when combustion temperature was raised, desulfurization rate increased at first and then decreased, anddesulfurization rate at the temperature of 850 C obviously was higher than that at other temperatures, With theincrease of Ca/S molar ratio, desulfurization rate increased obviously. However, desulfurization rate increased relatively slowly when Ca/S molar ratio increased from 1. 5 to 2. 0. The optimum Ca/S molar ratio of sludge coal waterslurry (S-CwS)should be 1. 5 when economic factor is taken into consideration. The desulfurization effect ofCa(OH), is better than that of CaCO, because the emission characteristics of So, is consistent with the decomposition pattern of Ca(OH)t, The test provides a solid basis for the industrial application of sludge coal water slurry.Key Words: sludge; coal water slurry(CWS); desulfurization; combustion隨著污水處理設(shè)施的普及和處理程度的深化,他輔助燃料混燒的方式進(jìn)行污泥的焚燒處理,相城市污水處理廠的污泥產(chǎn)量逐年迅速增長(zhǎng),如何妥對(duì)較高的投資和操作費(fèi)用在一定程度上限制了污泥善處置這些污泥已成為全球共同關(guān)注的課題.相焚燒的應(yīng)用關(guān)學(xué)者對(duì)各種污泥處理技術(shù)展開了廣泛的研相關(guān)學(xué)者對(duì)利用石油焦或造紙黑液摻制水煤漿究2-.污泥的焚燒處置具有減量化、無(wú)害化、資源以利用低品位能源和處理廢棄物展開了廣泛的研化等顯著優(yōu)點(diǎn),在歐美及日本等許多國(guó)家得到迅速究,并取得了較大的成果”.筆者根據(jù)污泥含水率發(fā)展-η,但機(jī)械脫水污泥含水率高,熱值較低,高的特點(diǎn)和水煤漿的理化特性,提出了基于水煤漿般無(wú)法單獨(dú)穩(wěn)定燃燒因此通常采用污泥與煤或其技術(shù)中國(guó)煤化工污泥摻入煤粉中CNMHG收稿日期:20090915基金項(xiàng)目:浙江省科技廳科研項(xiàng)目(No.2007C23032)作者簡(jiǎn)介:胡勤海(1962-),男,副教授,博士,主要從事固體廢棄物資源化方面的研究浙江大學(xué)學(xué)報(bào)(理學(xué)版)第37卷研磨制成污泥水煤漿根據(jù)筆者對(duì)污泥水煤漿成漿入空氣使其燃燒.并開啟煙氣分析儀對(duì)煙氣中的性及燃燒動(dòng)力學(xué)特性的研究發(fā)現(xiàn),當(dāng)污泥質(zhì)量摻混SO2等氣體成分進(jìn)行分析.到達(dá)給定燃燒時(shí)間后,停比例不高于10%時(shí),污泥水煤漿的物理特性和熱力止加熱,并將瓷舟取出置于干燥皿中冷卻至常溫學(xué)特性符合國(guó)家《水煤漿技術(shù)條件》(GB/T188552002)標(biāo)準(zhǔn)0,本文在上述研究的基礎(chǔ)上,進(jìn)一步研2結(jié)果與討論究污泥水煤漿的燃燒固硫特性,為污泥水煤漿技術(shù)的工業(yè)化應(yīng)用提供參考依據(jù)2.1燃燒溫度對(duì)污泥水煤漿燃燒固硫的影響般而言,在煤粉燃燒過程中,隨著燃燒溫度的1試驗(yàn)部分升高,其固硫率有所上升.但當(dāng)燃燒溫度超過1000℃時(shí),CaO容易發(fā)生燒結(jié)現(xiàn)象,使其活性下降,固硫試驗(yàn)物料率降低.若燃燒溫度高于1200℃,則生成的硫酸試驗(yàn)所用污泥水煤漿由山東微山煤,以及杭州鈣開始大量分解,固硫率進(jìn)一步降低.因此,煤粉四堡污水處理廠的中溫消化污泥和杭州七格污水處燃燒固硫存在一個(gè)最佳的燃燒溫度.水煤漿中含理廠的二沉池脫水污泥等按9:1質(zhì)量比根據(jù)濕法有30%左右的水分,燃燒溫度比煤粉低200℃左制漿工藝而制成所制得污泥水煤漿分別簡(jiǎn)稱為四右,從而減少了固硫劑的燒結(jié)有利于提高水煤漿堡污泥水煤漿( SB SCWS)和七格污泥水煤漿(QG的燃燒固硫率SCWS).四堡污泥水煤漿和七格污泥水煤漿的工污泥水煤漿燃燒固硫試驗(yàn)結(jié)果如圖2~圖5所業(yè)分析及硫含量如表1所示,由表可見四堡污泥水示其中,圖2和3為添加固硫劑CaCO3時(shí),燃燒溫煤漿的灰分略高于七格污泥水煤漿,而七格污泥水度和鈣硫摩爾比對(duì)四堡和七格污泥水煤漿燃燒固硫煤漿的固定碳含量略高于四堡污泥水煤漿率的影響圖4和5為添加固硫劑Ca(OH)2時(shí),燃表1污泥水煤漿的工業(yè)分析及硫含量燒溫度和鈣硫摩爾比對(duì)四堡和七格污泥水煤漿燃燒Table 1 Proximate analysis of sludge coal water slurry固硫率的影響.燃燒溫度是影響污泥水煤漿燃燒固硫的一個(gè)重要因素.由圖可見,隨著燃燒溫度從800工業(yè)分析/,adM,kg")硫分℃上升至950℃,污泥水煤漿的燃燒固硫率呈現(xiàn)出試樣水分灰分揮發(fā)份固定碳熱值S/明顯的先升高后降低的趨勢(shì),而且850℃時(shí)污泥水M/% A/% V/% Fc/% Qnet nd煤漿的燃燒固硫率明顯高于其他燃燒溫度條件下的微山煤6.2310.7931.6153.9320.8120.75燃燒固硫率.如四堡污泥水煤漿添加碳酸鈣固硫劑四堡污泥5.257.3137.255.447.081.53七格污泥5.0155.4337.512.059.021.52且Ca/S比為2時(shí),在850℃時(shí)其固硫率達(dá)到了5506%,而在800、900、950℃時(shí),其固硫率均在45%1.2試驗(yàn)裝置左右.究其原因,鈣基固硫劑受熱分解產(chǎn)生CaO實(shí)驗(yàn)在水平管式固定床上進(jìn)行,如圖1所示,整度過低不利于鈣基固硫劑的分解溫度過高又會(huì)導(dǎo)套實(shí)驗(yàn)裝置由熱電偶、加熱器、瓷舟、推桿、流量計(jì)氣瓶、煙氣分析儀和控制面版等部分組成管式固定致固硫劑因燒結(jié)而失去活性以及脫硫產(chǎn)物的分解床溫度調(diào)節(jié)范圍為室溫~1000℃,有效加熱段為800℃固硫劑CaCO300mm.實(shí)驗(yàn)時(shí)每次精確稱取0.5000g燃料于瓷舟中.在固定床達(dá)到設(shè)定溫度后把瓷舟推入中央,通數(shù)據(jù)采集流量計(jì)同舊CaS=0 CaS=1 Ca/s=1.5 Ca/s=2M凵中國(guó)煤化工堡污泥水煤漿N固定床反應(yīng)器煙氣分析儀CNMHG圖1固定床燃燒試驗(yàn)裝置fect of combustion temperature and Ca/sFig. 1 The combustion test device of fixed bed ovenmolar ratio on desulfurization rate of SB S-cwS第4期胡勤海,等:污泥水煤漿的燃燒固硫試驗(yàn)研究固硫劑CaCO鈣基固硫劑的基本原理就是通過CaO固體與SO2氣體反應(yīng)生成鈣鹽而實(shí)現(xiàn)固硫的.單純從化學(xué)反應(yīng)本身來看,增加鈣硫摩爾比有利于反應(yīng)向著固硫反應(yīng)方向進(jìn)行,鈣硫比越大,CaO與SO2接觸機(jī)會(huì)越多,固硫效果越好.但是當(dāng)鈣硫摩爾比較髙時(shí),隨著反應(yīng)的進(jìn)行,不僅生成的CaSO4覆蓋在CaO表面阻斷SO2氣體向CaO擴(kuò)散的通道,而且由于生成的CaSO4體積膨脹,填滿CaO內(nèi)的空隙,阻礙圖3燃燒溫度和鈣硫摩爾比對(duì)七格污泥水煤漿SO2向CaO內(nèi)部擴(kuò)散因此,當(dāng)鈣硫摩爾比較高時(shí),燃燒固硫影響進(jìn)一步增加鈣硫摩爾比,污泥水煤漿的燃燒固硫率Fig 3 Effect of combustion temperature and Ca/s上升趨于平緩.此外,CaCO3分解是一個(gè)吸熱反應(yīng)molar ratio on desulfurization rate of QG S-CWS過量的CaCO3會(huì)增加熱量損失和惡化污泥水煤漿2.2Ca/S摩爾比對(duì)污泥水煤漿燃燒固硫的影響燃燒,甚至可能會(huì)影響漿體的霧化燃燒,因此,在本Ca/S摩爾比是影響污泥水煤漿燃燒固硫的另文試驗(yàn)條件下,污泥水煤漿燃燒固硫的最佳鈣硫摩個(gè)重要因素.由圖2-5所示,隨著Ca/S摩爾比爾比應(yīng)該為1.5從0增加到2,污泥水煤漿的燃燒固硫率呈現(xiàn)出先2.3固硫劑種類對(duì)污泥水煤漿燃燒固硫的影響顯著上升,后趨于平緩的趨勢(shì).如七格污泥水煤漿添鈣基固硫劑種類對(duì)四堡和七格污泥水煤漿燃燒加固硫劑Ca(OH)2且燃燒溫度為850℃時(shí),隨著固硫率的影響如圖6和7所示,由圖可見,各工況條a/S摩爾比從0增加到1.5,固硫率從34.9%上升件下,Ca(OH)2的固硫效果略好于CaCO3,如四堡到5.12%,而進(jìn)一步增加Ca/S摩爾比至2時(shí),固污泥水煤漿燃燒溫度為850℃且Ca/S摩爾比為2硫率只上升到58.09%時(shí),Ca(OH)2的固硫率為59.06%,而CaCO3的固固硫劑caOH2硫率為55.06%□CaCO,燃燒溫度:850℃so[Ca(OH)Ca/S-0 Ca/S-l Cas=l5 Ca/S=2圖4燃燒溫度和鈣硫摩爾比對(duì)四堡污泥水煤漿燃燒固硫的影響Fig 4 Effect of combustion temperature and Ca/s圖6固硫劑種類對(duì)四堡污泥水煤漿固硫的影響molar ratio on desulfurization rate of SB s-cwsFig 6 Effect of desulfurizer kinds on desulfurization rateof sB s-cws固硫劑Ca(OHcaCO,燃燒溫度:850℃5o Ca(OH)Ca/S=0 Ca/S=1 Ca/s-1.5 Ca/S-2中國(guó)煤化工圖5燃燒溫度和鈣硫摩爾比對(duì)七格污泥水煤漿CNMHGCa/s=2燃燒固硫的影響失對(duì)藥死樂漿固硫的影響Fig 5 Effect of combustion temperature and Ca/sFig 7 Effect of desulfurizer kinds on desulfurization ratemolar ratio on desulfurization rate of QG S-cwSof QG sCwS470浙江大學(xué)學(xué)報(bào)(理學(xué)版)第37卷一般而言,若污泥水煤漿燃燒時(shí)SO2析出規(guī)律cessing Technology, 2002,75: 55-82.與鈣基固硫劑分解規(guī)律基本一致即可獲得最佳的固3] GUPTA R, GARG VK. 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