第32卷第4期燃料化學(xué)學(xué)報年JOURNAL OF FUEL CHEMISTRY AND TECHNOLOGY2004文章編號:0253-24092004)4-051003生物質(zhì)熱解油氣化試驗研究朱錫鋒', Venderboschr h1.中國科技大學(xué)生物質(zhì)潔凈能源實驗室,安徽合肥23026;2,. BTG Bion" asS Technology Group, Enschede,7500AE, The Netherlands)關(guān)鍵詞:生物質(zhì);生物油;熱解氣化中圖分類號∶TQ517.2文獻(xiàn)標(biāo)識碼:B生物質(zhì)是一種環(huán)境友好可再生資源可以通過直徑0.3mm這樣既能滿足生物油的霧化效果又多種途徑轉(zhuǎn)化為液體燃料。生物質(zhì)熱解液化即是在不致孔口被生物油中的固體顆粒堵塞:熱解部分由缺氧狀態(tài)下對生物質(zhì)進(jìn)行快速加熱然后再對熱解長200mn、直徑18mmn的無縫耐熱不銹鋼管組成,產(chǎn)物進(jìn)行快速冷凝最后獲得一種稱為生物油的液外繞加熱電阻絲加熱溫度通過可控硅溫控器進(jìn)行體燃料的技術(shù)。該技術(shù)以及生物油的特點主要有:調(diào)節(jié)泠卻部分由一強制空氣冷卻換熱器組成熱解熱解液化溫度為500℃遠(yuǎn)低于生物質(zhì)熱解氣化所高髙溫氣體流經(jīng)此換熱器后溫度能夠降低到50℃泠冷需800℃~1000℃,因而工藝難度較小泩生物油體凝部分由兩個洗瓶組成第一個是水洗瓶第二個是積能量密度約為20×10°kJ/m3為生物質(zhì)的10倍適酒精洗瓶用于過濾和吸收氣體中的固體殘余物計宜于遠(yuǎn)距離運輸和大規(guī)模儲存泩物油成分雖然復(fù)量部分由高精度容積式氣體流量計組成氣體計量雜但不同生物質(zhì)所產(chǎn)的生物油具有良好的相互混合后送至室外的特性便于大規(guī)模收集和轉(zhuǎn)化應(yīng)用泩物油屬于牛頓液體常溫下粘度系數(shù)為40cP~60cP與60號機械油相當(dāng)流動和霧化特性較好注生物油含水為20%氧質(zhì)量分?jǐn)?shù)為50%熱值為16MJ/kg~18MJ/kg熱值偏低熱穩(wěn)定性較差。圖1生物油無氧熱解試驗裝置流程圖由上可見生物油只是一種初級液體燃料雖然Figure 1 Flow chart of bio-oil gasification without oxygen可以直接用于鍋爐等燃燒熱力設(shè)備但用于內(nèi)燃機-piston pump i2--cracking tube 2-temperature controller還需要經(jīng)過精制加工如先對生物油進(jìn)行熱解氣化3--heat exchanger ,4--water washing bottle 4-ethanol制備合成氣然后再合成為高品位的液體燃料如甲washing bottle :5--flowmeter醇和二甲醚等1.2實驗方法由于生物油在高溫作用下容易發(fā)考慮到生物油氧質(zhì)量分?jǐn)?shù)較高氣化時不需要生聚合反應(yīng)而結(jié)焦因此為避免針形霧化器孔囗堵外部供氧或只需要提供少量的氧。本文在無外部供塞本實驗采用的方法為氧情況下對生物油進(jìn)行了熱解氣化試驗生物油中(1)試驗開始時,首先接通電源對熱解管進(jìn)行氫氧元素的質(zhì)量轉(zhuǎn)化率為8%而碳元素的轉(zhuǎn)化率空載加熱使其溫度較快上升到預(yù)定值只有55%由此說明生物油熱解氣化仍需外部提供(2)當(dāng)溫度達(dá)到預(yù)定值后開啟柱塞泵,先將酒少量氧氣作為氣化劑。精按實驗要求旳流量泵入熱解管,以清洗系統(tǒng)內(nèi)部實驗部分管路和縮小正式實驗時的溫度波動1.1實驗裝置圖1所示是生物油熱解氣化試驗3)當(dāng)溫度再次上升到預(yù)定值后將酒精切換裝置流程圖,它主要包括進(jìn)料、熱解、冷卻、凈化和計為生物油進(jìn)行正式試驗并開始計時量五個部分。其中進(jìn)料部分由一臺柱塞泵組成泵(4)正式實驗結(jié)束之前,先將生物油切換為酒的流量在2gmn-100g/min無級可調(diào)泵的出口是精并停止計時若干分鐘后再關(guān)閉加熱電源和柱塞針形霧化器孔口直徑可以變換試驗采用的孔口泵電源朱錫鋒等:生物質(zhì)熱解油氣化試驗研究511〔5)試驗前后對洗瓶進(jìn)行稱重并記錄氣體流1.3實驗原料實驗原料是一種木屑熱解液化得量計的讀數(shù)。為保證計量精度在前后時間段由酒到的生物油其主要特性和元素組成分別列于表1精熱解產(chǎn)生的氣體經(jīng)換熱器冷卻后由旁路引向室和表2。外而不經(jīng)過洗瓶和流量計表1生物油的主要特性Table 1 Main characteristics of bio-oilDensityCaloric valueM a/%oo kg m")Q(MJ kg") n(mms)0.02.8l190表2生物油的元素分析Table 2 Ultimate analysis of bio-oilUltimate analysis w /Element analysis w. /10CH ON SCa41.50.20.0091.4實驗參數(shù)為穩(wěn)定荻取生物油熱解氣化的實表3為生物油熱解氣經(jīng)過氣相色譜分析得到的驗數(shù)據(jù)每次試驗所采用實驗參數(shù)均相同即熱解反氣體組分以及由這些組分計算荻得的熱解氣的質(zhì)應(yīng)溫度控制在(1000±10)℃;熱解管內(nèi)的壓力為量、密度和熱值。由表可見3000Pa,等于熱解系統(tǒng)的流動阻力損失泩生物油泵(1)生物油熱解氣氧氣組分為零氮氣組分很入質(zhì)量流量為3.5g/min正式試驗10min。低組分最高的四種氣體依次分別是一氧化碳、氫2結(jié)果與分析氣、甲烷和二氧化碳。2.1熱解氣組分與特性按照上述實驗方案本研(2)生物油熱解氣的熱值為21.09M/kg乘以究對生物油熱解氣化進(jìn)行了若干次重復(fù)試驗每次燃?xì)饧瓤捎米鳛榫用裆钊細(xì)庖部勺鳛楣I(yè)原料試驗均用去35g生物油并產(chǎn)生0.024m3熱解氣,數(shù)據(jù)重復(fù)性較好,用于生產(chǎn)合成氣。表3生物油熱解氣的組分與特性Table 3 Concentration and properties of cracked gas from bio-oiH O, N CH Co CO2 C H CHCH CH Cracked gasVolume o /%031.5102016.9237.739.384.000.120.090Density p( kg m)0.081,291,130.651.131.781,131.211.781,860.610.000.062.6210001.080.030.040.02Caloric value Q人Mkg)141.650.00.0554510.090.0050.2551.8348.8749.9421.0922熱解氣化質(zhì)量衡算試驗使用35g生物油熱個重要評價指標(biāo)是其質(zhì)量轉(zhuǎn)化率表5所列是根據(jù)解產(chǎn)生了18.7g氣體試驗前后兩只洗瓶的質(zhì)量增上述實驗結(jié)果計算獲得的碳、氫、氧以及這三種元素量為15.3g。據(jù)此可對生物油熱解氣化進(jìn)行質(zhì)量平總的質(zhì)量轉(zhuǎn)化率。由于生物油中的水分和灰分不能衡計算結(jié)果列于表4。由表可見尚有少量殘余物熱解氣化故此處采用的計算基準(zhǔn)是干燥無灰基。質(zhì)如焦炭等粘附在管道內(nèi)壁上。表5生物油熱解氣化質(zhì)量轉(zhuǎn)化率表4生物油熱解氣化質(zhì)量衡算Table 5 Mass conversion efficiency of bio-oil gasificationTable 4 Mass balance of bio-oil gasificationElementC H O (C+H+O)Input mass ma/gItput mass mad /gBio-oil md/g15.381.6710.3927,44cracked gas washing liquids n/%15.38.481.448.7818.70512燃料化學(xué)學(xué)報致謝:本項研究是筆者在荷蘭BTG生物質(zhì)技術(shù)研究所從事訪問學(xué)者期間完成的在此謹(jǐn)向BTG表示衷心感謝參考文獻(xiàn)[1]蘇學(xué)泳王智微程從明等.生物質(zhì)在流化床中的熱解和氣化研究J.燃料化學(xué)學(xué)報,2000,2X4)298-30(SU Xue-yong, WANG Zhi-wei, CHENG Cong-ming, et al. Study on biomass pyrolysis and gasification in a fluidized bed J]Journal of Fuel Chemistry and Technology, 2000, 284): 298-305.)[2]侯斌呂子安李曉輝籌.生物質(zhì)熱解產(chǎn)物中焦油的催化裂觚J]燃料化學(xué)學(xué)報,2001,∞1):0-75(HOU Bin, LU Zi-an, LI Xiao-hui, et al. Catalytic cracking of tar derived from biomass pyrolysis J ] Joumal of Fuel Chemistryand Technology,2001,291):70-75.)[3]郭建維宋曉銳崔英德.流化床反應(yīng)器中生物質(zhì)的催化裂解氣化研究J]燃料化學(xué)學(xué)報,20012X4)319-322GUO Jian-wei, SONG Xiao-rui, CUI Ying-de. Catalytic pyrogasification of biomass in a fludized bed reacto J]. Joumal of FrChemistry and Technology, 2001, 294): 319-322.)[4]王智微唐松濤蘇學(xué)泳等.流化床中生物質(zhì)熱解氣化的模型硏究J.燃料化學(xué)學(xué)報,2002,3(4)342-346WANG Zhi-wei, TANG Song-tao, SU Xue-yong, et al. A study on model from biomass pyrolysis and gasification in fluidized bed[JI. Joumal of Fuel Chemistry and Technology 2002, 304): 342-346[5]呂鵬梅常杰熊祖鴻等.生物質(zhì)在流化床中的空氣-水蒸汽氣化研究J]燃料化學(xué)學(xué)報,206,34)305-310( LU Peng-mei, CHANG Jie, XIONG Zu-hong, et al. An experimental research on biomass air-steam gasification in a fludized bedechnology,2003,3X4):305-310.)WAGENAAR B M PRINS W, VAN SWAALJ W P M. Pryolysis of biomass in the rotating cone reactoR D ] Twente UniversityEnschede, the Netherlands 1984[7] RADOVANOVIC M, VENDERBOSCHR H, PRINS W, et al. Some remarks on the viscosity measurement of pyrolysis liquids[J]. Biomass Bioenergy 2001, 228):209-222[8]吳創(chuàng)之凃冰燕羅曾凡等.生物質(zhì)中熱值氣化技術(shù)的分析與探訶J]煤氣與熱力,1995,132)8-14(WU Chuang-zhi, XU Bing-yan, LUO Zeng-fan, et al. Analysis of biomass gasification for MHV fuel gas[ J ] Gas &&Heat1995,12):8-14.)[9]朱錫鋒,生物質(zhì)液化制備合成氣的研究J]可再生能源200(1)11-14(ZHU Xi-feng. Study on syngas made from biomass pyrolysis[ J ] Renewable Energy, 2003(1): 11-14)[⑩0]朱錫鋒, VENDERBOSCH H王俊三.燃料理論空燃比與其高位熱值之間的關(guān)系J中國科技大學(xué)學(xué)報,204,341)1-(ZHU Xi-feng, VENDERBOSCH R H, WANG Jun-san. Correlation between stoichiometrical ratio of air to fuel and its higlheating valud J]. Joumal of University of Science and Technology of China, 2004, 3( 1): 111-115.)Experimental research on gasification of bio-oilderived from biomass pyrolysisZHU Xi-feng Venderbosch R h(I. Laboratory of Biomass Clean Energy University of Science and Technology of China, Hefei 230026,China2. BTG Biomass Technology Group, Enschede, 7500.AE, the NetherlandsAbstract: Biomass can be converted into bio-oil by pyrolysis with high heating and cooling rates. Bio-oil is a crudeoil which can be upgraded into high quality liquid fuels, for instance it can be first gasified into syngas and then sythesized into methanol, dimethyl ether and so on. Considering bio-oil has high oxygen content bio-oil gasificationwithout any external supply of oxygen has been performed. The result shows that the mass conversion efficiencies ofoxygen and hydrogen elements could reach as high as 85 %, but that of carbon is only 55%. Hence, the external oxy-gen supply should be needed to improve the mass conversion efficiency of bio-oil gasificationKey words: biomass bio-oil i gasificationAuthor introduction: ZHU Xi-feng( 1962.), male, Associate Professor engaged in the research of biomass conversion