第29卷第5期華北水利水電學院學報Vol 29 No 5008年10月Journal of North China Institute of Water Conservancy and Hydroelectric Power文章編號:1002-5634(2008)05-0083-03秸稈合成氣合成甲醇的催化劑優(yōu)化實驗研究杜磊(華北水利水電學院,河南郟州40011)摘要:生物質(zhì)能是一種可再生能源,為了研究秸稈類生物質(zhì)(農(nóng)業(yè)廢棄物)轉化為燃料甲醇和生物質(zhì)能的有效利用,采用熱化學方法在下吸式固定床氣化爐中生產(chǎn)了低熱值秸稈燃氣,對該燃氣進行脫硫、脫氧、焦油催分解、純化、配氫等優(yōu)化實驗制備出秸稈合成氣,在直流流動等溫積分反應器中進行了催化合成甲醇的催化實驗,在235℃和5MPa條件下進行了催化劑種類及粒度對甲醇合成的影響實驗實驗結果表明:合成甲醇的適宜催化劑型號為C301,最優(yōu)化顆粒粒度為0.833mmx0.351mm.該研究為生物質(zhì)(秸稈)氣催化合成甲醇的深人研究提供了基礎數(shù)據(jù)關鍵詞:催化劑;秸稈;合成氣;粒度;甲醇合成中圖分類號:S216文獻標識碼:A生物質(zhì)作為可再生能源不僅資源豐富、無污染可再生而且是可再生能源中惟一可以轉化為液態(tài)1實驗燃料和化學品的碳資源生物質(zhì)催化合成甲醇等化1.1試驗主要儀器及其生產(chǎn)廠家學品和液態(tài)燃料技術是生物質(zhì)能高品位開發(fā)利用技JMQ系列秸稈氣化機組,河南省宏越秸稈氣化術之一發(fā)達國家合成甲醇的生物質(zhì)主要是木材碎技術有限公司;JA-5槽直流流動等溫積分反應器,片、甘蔗渣等,采用氧氣和水蒸汽為氣化劑,氣化工江蘇海安石油科研儀器廠;zK-50可控硅電壓調(diào)整藝技術復雜,設備昂貴,制備出髙熱值合成氣后再催器,云南儀表廠;TCS-A智能溫度測控儀(控溫精化合成甲醇].中國是一個農(nóng)業(yè)大國,生物質(zhì)資源度為±0.1℃),南京攀達電子儀器廠;GC-900C型極為豐富,僅秸稈一項年產(chǎn)量即達6億多t,這些秸氣相色譜儀,中科院天樂精密科學儀器有限公司稈大部分被廢棄或隨意焚燒,嚴重污染環(huán)境,造成巨(上海);G2v-5/200隔膜壓縮機,北京第一通用機大的資源浪費.目前,全國已建成數(shù)百處秸稈氣化械廠站,生物質(zhì)氣化主要設備為上吸式及下吸式固定床1.2試驗材料氣化爐,用空氣做氣化劑,生產(chǎn)工藝技術及設備簡單選用鄭州東郊當年新收獲的玉米秸稈為原材價廉,生物質(zhì)燃氣為含少量焦油的低熱值燃氣,該氣料,經(jīng)曬干并粉碎至2~3cm,在JMQ系列秸稈氣化體中氮氣及二氧化碳含量較高,氫氣含量較低,必須機組上,以空氣為氣化劑,制備出秸稈原料氣.將原經(jīng)過處理制得合成氣后才能進行甲醇合成低熱值料氣經(jīng)脫硫、除氧、分解焦油、凈化、配氫等處理后秸稈燃氣主要用于直接燃燒做飯,少量用于取暖和制備出秸稈合成氣,合成氣組成見表1發(fā)電,生物質(zhì)能利用率較低.為使數(shù)量巨大的生物質(zhì)表1生物質(zhì)合成氣組成資源得到充分、高效的利用,加快實現(xiàn)生物質(zhì)合成甲COC.H。醇的工業(yè)化步伐筆者進行了秸稈合成氣合成甲醇4661-3040120-13.165980.76-1.16327-45.38的催化劑實驗研究注:CH。=CH4,C2H2,C2H4,C2H收稿日期:2008-07-21中國煤化工基金項目:河南省教育廳科技攻關項目(2007610008)作者簡介:杜磊(1958-),女河南范縣人,華北水利水電學院教師,主CNMHG華北水利水電學院學報2008年10月1.3實驗流程與實驗條件選用3種低壓銅基催化劑C301,C302,NC306,其對如圖1所示,生物質(zhì)合成氣自鋼瓶①經(jīng)穩(wěn)壓閥應的實驗條件為:催化劑粒度為16-20目,進口合③將壓力控制到主反應壓力后進入反應器②反應成氣組成為112%0,5.98%CO2,3273%N2,后氣體經(jīng)冷凝器⑤分離出甲醇和水,不凝氣體經(jīng)減0.76%C,Hn,46.61%H2催化劑粒度優(yōu)化實驗條件壓閥降至常壓由流量計⑥計量后,一部分氣體放為:催化劑型號為C301,催化劑重量為49246g,空另一部分流向氣相色譜儀①,由色譜T作站及電催化劑粒度(目)為16~20,20-40,40-60,60腦⑩自動采集和處理數(shù)據(jù)80,進口合成氣組成為13.16%CO,9.84%CO245.38%N2,1.16%CH,30.4%H2,催化劑的活化和實驗方法見文獻[10]2結果分析2.1催化劑的優(yōu)化實驗對每種催化劑,采用改變進口氣流量進行實驗,結果見表2.由表2可知:對C301,C302催化劑,CO轉化率隨合成氣進口流量的逐漸增大而逐漸變小;器:⑤一冷凝器:⑥—流量計:(一壓縮機:⑧-溫度控制器:⑨一8對NC306催化劑則是先升高后逐漸降低;對C301開關:①一溫度顯示器;①氣相色譜僅;⑩一載氣瓶:①一數(shù)據(jù)處催化劑CO2轉化率隨著進口合成氣流量的不斷增理器;①一計算機大的變化趨勢為由高到低再升高降低是倒S型,而圖1試驗裝量系統(tǒng)圖對C302和NC306催化劑則為由低到高再降低升高生物質(zhì)合成氣在催化劑作用下,可能發(fā)生CO,呈S型變化;甲醇時空收率隨進口合成氣流量的不CO2與H2反應合成甲醇的反應及生成CO2和H2斷增大各催化劑的變化趨勢與CO2轉化率變化趨的逆反應前2個反應分子數(shù)目變小且放熱,最后一勢相同,且C301催化劑甲醇時空收率最大,C302催個反應吸熱且反應前后分子數(shù)目相同由化學反應化劑次之,NC306催化劑的稍微小些試驗結果表理論可知,增加壓力、降低溫度對前2個合成反應明:C301,C302,NC3063種催化劑均可作為秸稈類有利,但考慮到設備投資和催化劑活性,反應壓力控生物質(zhì)合成甲醇的催化劑,其中,C301催化劑催化制為5MPa,反應操作溫度235℃.催化劑優(yōu)化實驗效果最佳.表2催化劑的活性試驗結果進口氣流量c0出口c0出口甲醇c0轉化C02轉化甲醇時空收率(mol,b)摩爾分率摩爾分率摩爾分率摩爾分率摩爾分率(kg·(kgnb)“)0.0741620.06l1990.0541630.3982630.0766220.2900222c3011.0523380.0814820.0617610.0421850.3242640.0475720.2648761.3061010.0832980.0603860.0415130.3083430.0676100.3239131.7160850.0896090.0585600.0346980.2464580.0842802.0978130.0938520.0591800.0273060.1997140.0616080.3514332.4690810.0970890.0586640.0231710.1655670.0624440.353767C3020.8992770.0785180.0623360.0458150.3531730.0450982379978c3021.2513970.0855150.0603960.0381280.2854660.0615890.279557C3021.5943400.0935870.0590170.0279570.2029550.0653510.266187C3021.9632080.0941600.0577780.0289693389852.3121120.1002780.0571250.006630.1340060.0826380.28931012C3022.4722040.1020060.0579600.0167680.1124400.0622120.25291613NC3060.9250480.0853040.0623180.0355290.2837690.027030.19604614NC3061.2916440.0837270.0623410.0378900.3000.0309440.29064815Nc306l.8195360.0931550.0598180.020.30194216NC3062.1333220.0962940.0609580.0中國煤化工17Nc3062.4910260.0999400.0590400.01YHSCNMHG0.28049018Nc3062,6919300.0997470.0597280.0175143480.0349980.29101519NC3062.9990900.1002600.0598870.0164940.1271740.0305280.305944第29卷第5期杜磊:秸稈合成氣合成甲醇的催化劑優(yōu)化實驗研究2.2催化劑粒度優(yōu)化實驗不同粒度的催化劑優(yōu)化實驗結果見表3考文獻[1] Goudeau Jean Claude, Bourreau Alain, Souil Francois. An表3實驗結果隨催化劑粒度的變化investigation on methanol catalytic synthesis from biomass催化劑粒度/目gases[ J]. Energy Res, 1983(3): 191-202O#R*/% 12. 37 16.98 18. 79 20. 23 [2] Corte P, Lacoste C, Traverse J P. Gasifition and catalyticcO2轉化率/%0.300.270.872.01conversion of biomass by flash pyrolysis[ J].J. Anal Appl1046(kKm:b),1023614391610Pyrolysis,1985,7(4):323-325.[3] Baker E G, Brown M D Catalytic steam gasification of ba-gasse for the production of methanol[ J]. Energy Biomass由表3可知,CO轉化率及甲醇時空收率均隨催Wastes,1984,8:651-674.化劑粒度變小而增大,CO2轉化率出現(xiàn)相同的變化[4] Beenackers AA C M, Van swaaij W P M. Methanol from趨勢,但20~40目時例外;甲醇時空收率隨催化劑ood[ J]. Int. J. Sol. Energy, 1984, 2(5): 349-367.粒度的目數(shù)增大而逐漸變大,但變化幅度較小由于[5] Palmer eric R. Gasification of wood for methanol Produc催化劑粒度越小,目數(shù)越大,使氣體通過單位高度催tion[ J]. Energy Agric., 1984, 3 (4): 363-375化床的壓力降增大,動力消耗增大通過綜合考慮,[6] Specht M, Bandi a, Baumgart F,ta, Synthesis of metha催化劑粒度以20-40目為宜,即最佳粒度為nol from biomass/C0, resources[ c]//Greenhouse GasControl Technol. Proc. Int Conf. 4th, 1998: 723-727.0.833mmx0.351mm.[7] Plzak Vojtech, Wendt Hartmut Energetic utilization of bio-3結語mas[J].Chem.lng.Tech.,1992,64(12):1084-1095[8] Demirbas Ayhan Biomass resources for energy and chemi-1.農(nóng)業(yè)廢棄物——秸稈通過熱化學轉化等處理cal industry[ J]. Energy, Educ. Sci. Technol, 2000, 5(1)后制得的合成氣可直接催化合成燃料甲醇;21-45.2在催化合成反應溫度和壓力分別為235℃,[9]房鼎業(yè)姚佩芳朱炳辰甲醇生產(chǎn)技術及進展[M]·上5MPa的條件下,秸稈合成氣催化合成燃料甲醇的海:華東化工學院出版社,1990適宜催化劑為C301,催化劑顆粒最佳粒度為10]朱靈峰張百良梁庚白等.玉米秸秤熱化學法合成0.833mmx0.351mm,該研究為生物質(zhì)(秸稈)氣甲醇的研究[]河南農(nóng)業(yè)大學學報,2003,37(4):400催化合成甲醇的深入實驗提供了理論數(shù)據(jù)Study on the Optimum Experiments of Methanol Synthesis Catalyst from Cornstalk SyngasDU LeiNorth China Institute of Water Conservancy and Hydroelectric Power, Zhengzhou 450011, China)Abstract: Biomass energy is a renewable and potential resource. In order to research the conversion of cornstalk biomass( the agricultural residues)into the fuel methanol and the effective utilization of biomass energy, the low-heat-value cornstalk gas is produced by themeans of the thermo-chemical method in the down-flow fixed bed gasifier. The comstalk gas is purified and the technical proceduresch as desulfurization, catalytic cracking of tar, deoxygenation, purification and hydrogenation are performed, and the cornstalk synthesisgas is prepared. The catalytic experiments of methanol synthesis with cornstalk syngas are carried out in a tubular flow integral and iso-thermal reactor, the effect of the catalyst types, catalyst particle size is investigated at 235 C under the pressure 5 MPa. The experital results indicat that the proper catalyst for the synthetic reaction is C301 and the optimum catalyst size is 0. 833 mm xO. 351 mmThis study can provide basic data for the further studies of methanol syntheKey words: catalyst; cornstalk; syngas: particle size; methanol synthesisYHE中國煤化工CNMHG