第32卷第6期西安科技大學(xué)學(xué)報(bào)Vol 32 No 62012年11月JOURNAL OF XI AN UNTVERSITY OF SCIENCE AND TECHNOLOGYNov.2012文章編號(hào):1672-9315(2012)06-0753-06輕度熱解提質(zhì)褐煤孔結(jié)構(gòu)研究葉普海',周敏',劉恭欣2,錢春梅',楊絮!,陳恒寶(L.中國(guó)礦業(yè)大學(xué)化工學(xué)院,江蘇徐州22116;2.新疆天池能源有限責(zé)任公司,新疆昌吉831100摘要:對(duì)霍林河褐煤熱重分析的基礎(chǔ)上,在管式爐中進(jìn)行輕度熱解實(shí)驗(yàn),通過低溫N2吸附研究了熱解前后煤樣的孔隙特性,考察不冋熱解溫度,恒溫時(shí)間對(duì)煤孔結(jié)構(gòu)的影響。結(jié)果表明:熱解溫度和恒溫時(shí)間對(duì)褐煤的孔結(jié)構(gòu)分布影響較大。褐煤和提質(zhì)煤的吸附脫附等溫曲線都存在吸附回線,但褐煤比提質(zhì)褐煤的吸附回線寬,說明提質(zhì)煤的微孔數(shù)量減少,大孔數(shù)量増多。與褐煤相比,輕度熱解處理后,褐煤的比表面積減少,孔容減小,平均孔徑增大。關(guān)鍵詞:褐煤;熱解;提質(zhì);孔隙特性;吸附/脫附曲線中圖分類號(hào):TQ531文獻(xiàn)標(biāo)志碼:A0引言褐煤是世界上重要的煤炭資源之一,約占世界煤炭資源的40%以上。褐煤全水分高達(dá)20%~60%收到基低位發(fā)熱量介于11.71-16.73MJ·kg1,高水分,高含氧量,低發(fā)熱量,同時(shí)褐煤易風(fēng)化和自燃的特性,不適合遠(yuǎn)距離運(yùn)輸限制了褐煤的廣泛利用-3。輕度熱解使褐煤經(jīng)受脫水和熱分解作用轉(zhuǎn)化成具有似煙煤性質(zhì)的提質(zhì)煤,伴隨著一些煤的組成和結(jié)構(gòu)的變化。熱解使褐煤得到提質(zhì),有利于利用、運(yùn)輸貯存和提高綜合經(jīng)濟(jì)效益,對(duì)褐煤高效潔凈利用意義重大45。文中通過考察不同熱解條件下霍林河褐煤吸附/脫附性質(zhì),分析熱解條件對(duì)褐煤孔結(jié)構(gòu)的影響,解析褐煤在輕度熱解過程中孔結(jié)構(gòu)的變化。1試驗(yàn)部分1.1樣品及性質(zhì)試驗(yàn)采用的是霍林河褐煤,該煤樣的煤質(zhì)分析數(shù)據(jù)見表表1褐煤煤質(zhì)分析Tab 1 Proximate and ultimate analyses of ligniteHg指標(biāo)18.721.2實(shí)驗(yàn)儀器熱重分析采用德國(guó) NETZSCH公司STA409C型 DTA/DSC-TG同步綜合熱分析儀溫度控制范圍0~600℃,靈敏度1.25μ,樣品質(zhì)量0~500mg,熱量測(cè)量范圍0~500mV,差熱靈敏度18μV/mV,差熱測(cè)量范圍0~5000μV.褐煤輕度熱解在管式爐中進(jìn)行,電爐型號(hào)GR-3-9,額定電壓380V,額定功率3.5kW,額定溫度950℃,控制器型號(hào)TCW-32B褐煤比表面積和孔結(jié)構(gòu)等性質(zhì)是由美國(guó)康塔儀器公司生產(chǎn)的1-mnH表面孔徑測(cè)定儀測(cè)定,以N2為吸附質(zhì)在液氮溫度(-196℃)下進(jìn)行吸附,孔容,THE中國(guó)煤化分析結(jié)果由CNMHG收稿日期:2012-05-10通訊作者:葉普海(1989-),男,四川綿陽(yáng)人,碩士研究生,從事煤炭潔凈綜合利用技術(shù)研究75西安科技大學(xué)學(xué)報(bào)2012年計(jì)算機(jī)聯(lián)機(jī)計(jì)算得出。1.3試驗(yàn)過程試驗(yàn)褐煤進(jìn)行熱重測(cè)試分析,確定合適的輕度熱解溫度區(qū)間。測(cè)試條件為樣品質(zhì)量10±0.1mg;保護(hù)載氣高純N2;載氣流速100mLmin';升溫速率30℃·min,終溫900℃。褐煤輕度熱解試驗(yàn)裝置如圖1所示。將盛有15g分析煤樣的煤1-氮?dú)怃撈?-轉(zhuǎn)子流量計(jì)3-管式妒4-反應(yīng)罐5-煤槽槽放入反應(yīng)管內(nèi),煤樣粒度1~3mm,用量15g左右,向反應(yīng)管內(nèi)以6-熱電偶7-程序控制器400mL·min-速率通入N2約2~3min將反應(yīng)管內(nèi)空氣排出,然后通圖1褐煤輕度熱解試驗(yàn)裝置過程序控制器進(jìn)行加熱。根據(jù)熱重分析所確定的輕度熱解溫度區(qū)間Fig1 Experimental apparatus of lignite選擇合適的熱解溫度,查閱相關(guān)文獻(xiàn)選擇合適的恒溫時(shí)間。mild pyrolysis upgrading按照比表面孔徑測(cè)定儀的操作規(guī)范對(duì)熱解處理后的煤樣進(jìn)行比表面分析測(cè)定。2結(jié)果與討論2.1褐煤的熱重分析圖2為試驗(yàn)所用霍林河褐煤的熱重分析圖。由圖可知:DTG曲線在100℃附近出現(xiàn)一個(gè)明顯的脫水峰,溫度上升至大約150℃時(shí),峰型趨于平穩(wěn),褐煤脫水結(jié)束。TG曲線在200~250℃出現(xiàn)一個(gè)平臺(tái),說明褐煤在該溫度范圍內(nèi)基本不發(fā)生反應(yīng)。到250℃之后,TG曲線開始下滑,在低于350℃范圍內(nèi),TG曲線下滑比較平緩,在350~600℃范圍內(nèi),曲線迅速下降,600℃之后TG曲線趨于平緩。說明褐煤在250℃左右開始熱分解,350℃之前只發(fā)生輕度熱解,350~600℃褐煤發(fā)生劇烈分解。450℃左右DIG曲線出現(xiàn)一個(gè)非常明顯的峰,該峰可能為褐煤中可揮發(fā)性氣體和焦油析岀產(chǎn)生的失重峰,該峰比一般褐煤的失重峰大,表明霍林河褐煤的揮發(fā)分較髙。根據(jù)以上分析結(jié)果,褐煤輕度熱解溫度選在250~350℃范圍,該溫度范圍內(nèi)主要脫出褐煤中部分活性含氧基團(tuán),褐煤分子的主體結(jié)構(gòu)基本不發(fā)生變化。2.2吸附/脫附等溫曲線根據(jù)BET吸附理論基本假定,吸附和凝聚現(xiàn)象可作為計(jì)算100孔徑分布的依據(jù),不同分壓下孔隙中的吸附量對(duì)應(yīng)著相應(yīng)尺寸孔的孔體積,由此可以得到孔徑大小隨孔體積的分布6-7。除9去少數(shù)個(gè)別情況外,吸附等溫曲線可以分5種類型,即第Ⅰ類吸附等溫曲線、第Ⅱ類吸附等溫曲線…第④4類吸附等溫曲線。5種80吸附等溫曲線的類型反映了5種不同類型的吸附劑的表面特性、孔分布、和吸附物質(zhì)與吸附劑之間的相互作用的性質(zhì)8-10褐煤及提質(zhì)褐煤(保溫時(shí)間30mi,熱解溫度250,300,350℃)圖2褐煤的熱失重曲線的N2吸附/脫附等溫曲線如圖3所示。Fig 2 Thermo-gravimetric curve of ligniteP和P分別是測(cè)試壓力和N2的飽和壓力;ⅴ是液氮的吸附量。圖3所示表明褐煤及提質(zhì)褐煤的低溫N2吸附等溫線的形態(tài)均屬于第Ⅲ類吸附等溫線吸附質(zhì)與吸附劑表面之間存在較弱的相互作用,煤樣表面發(fā)生多層吸附,其中有50A以上的孔,且孔徑一直增加21。在相對(duì)壓力P/P很低的情況下褐煤吸附曲線和脫附曲線分離,說明褐煤中有開放性透氣性孔,并以小孔徑孔居多。褐煤在不同溫度下熱解30min,出現(xiàn)吸附回線時(shí)的相對(duì)壓力幾乎都在0.5~0.99之間,說明經(jīng)輕度熱解后褐煤中開放性小孔數(shù)變少較大的孔數(shù)量增多,在相對(duì)壓力PP低于0.5的區(qū)間沒有產(chǎn)生吸附回線,說明在褐煤相對(duì)微小的孔隙中有一端開放一端封閉的孔。吸附等溫線的起始部分向上翹,可能是的階段:隨著相對(duì)壓力的增加,吸附急劇上升,在接近飽和蒸汽壓煤中有些孔發(fā)生了毛細(xì)凝聚現(xiàn)象,使吸附量急劇增加13YHE嗎附向多八子層吸附過渡中國(guó)煤化工CNMHG主要是由于第6期葉普海等:輕度熱解提質(zhì)褐煤孔結(jié)構(gòu)研究755吸附曲線吸附曲線12脫附曲線脫附曲線250℃00.00.2040.60.81.0081.0吸附曲線吸附曲線脫附曲線◆脫附曲線300℃350℃C00.204060.81.0圖3褐煤和提質(zhì)褐煤的吸附/脫附等溫曲線ig. 3 Adsorption and desorption isotherms of lignite and upgrading coal2.3熱解溫度對(duì)褐煤孔隙結(jié)構(gòu)的影響褐煤及不同熱解條件下提質(zhì)褐煤的總比表面積為大孔、中孔以及微孔的比表面積之和。圖4所示為根據(jù)BET理論計(jì)算得到不同輕度熱解溫度條件下(恒溫時(shí)間30mn)提質(zhì)褐煤的比表面積、平均孔徑、孔容數(shù)據(jù)。褐煤的孔隙結(jié)構(gòu)數(shù)據(jù)見表2輕度熱解后提質(zhì)褐煤的總比表面積從表2褐煤比表面積、孔容和平均孔徑3.16m2·g降低到2.92m2·g-2,孔容由Tab.2 Specific area, pore volume and average pore size of lignite0.0227c·g減少至0.0209c·g-,平樣品比表面積/m2·g-平均孔徑10-1m孔容/c·g-1均孔徑從304.60A降低到273.90A.熱解溫褐煤度范圍內(nèi),以液態(tài)形式停留在煤粒表面和空隙結(jié)構(gòu)中的焦油等粘稠液相組分阻塞孔道使得褐煤比表面積→比表面積m·g1400減小。隨著溫度的升高,褐煤的比表面積與孔容的變化不亠平均孔徑10"m孔容!c"g0.028致,其主要原因是比表面積的大小除與孔容相關(guān)外,還與孔徑v231的分布有關(guān)。輕度熱解后,褐煤中小孔減少較大的孔發(fā)育,30e1024300℃以后,褐煤揮發(fā)分快速析出,孔隙結(jié)構(gòu)變得更加發(fā)達(dá),320R同時(shí)伴隨出現(xiàn)更多的二次孔導(dǎo)致平均孔徑下降?？兹莸慕档土?90.020可能是因?yàn)橄鄳?yīng)孔徑分布趨向孔徑比較小的部分。2.4恒溫時(shí)間對(duì)褐煤孔隙結(jié)構(gòu)的影響熱解溫度℃C圖5為根據(jù)BET理論計(jì)算得到不同輕度熱解時(shí)間條件下(熱解溫度350℃)提質(zhì)褐煤的比表面積、平均孔徑、孔圖4熱解溫度對(duì)提質(zhì)褐煤孔隙結(jié)構(gòu)的影響Fig 4 Influence of the pyrolysis temperature on數(shù)據(jù)。upgrading coal pore structure輕度熱解后提質(zhì)褐煤的比表面積由2增加到98m2·g-,孔容由0.0209cc·g降至到0.0233c·g-1,平均孔徑由34290A下降至285.90A.隨著恒溫時(shí)間的增長(zhǎng),提質(zhì)褐煤比表面積逐漸增大,平均孔徑和孔容YH中國(guó)煤化工1時(shí)達(dá)到最小值整體呈現(xiàn)近似“V"型變化規(guī)律。恒溫時(shí)間不同,褐煤軟化程度CNMHG孔的塌縮,改變了褐煤中孔的數(shù)量與分布,導(dǎo)致平均孔徑和總孔容發(fā)生變化。隨著恒溫時(shí)間的增長(zhǎng),煤粒內(nèi)部揮發(fā)分大量析出,伴隨生成很多小孔,褐煤的比表面積隨之增大)。在350℃熱解溫度下,軟化變形煤粒中半析756西安科技大學(xué)學(xué)報(bào)2012年出態(tài)焦油阻塞煤中孔隙,某些孔由于表面張力的作用孔徑減2x·比表面積m:g平均孔徑10m0.024小甚至關(guān)閉,最終提質(zhì)褐煤的平均孔徑和孔容減小,在30min孔容/e:g至最小值,此后由于揮發(fā)分析出大量形成的毛細(xì)孔以及被阻30340罕10023塞孔隙的再次打開使提質(zhì)褐煤平均孔徑和孔容在一定程度上320又增大。恒260.0222.5熱解條件對(duì)褐煤孔徑分布的影響300根據(jù) IUPAC的分類法:0~2m為微孔,2~50mm為中L,>50mm為大孔。圖6所示為根據(jù) BJH Desorption Pore恒溫時(shí)間/minDistribution Report數(shù)據(jù)中的dv/ dd Pore volume對(duì) Average恒溫時(shí)間對(duì)提質(zhì)褐煤孔隙結(jié)構(gòu)的影響Diameter作圖得到的褐煤及不同熱解條件下提質(zhì)褐煤的孔徑5 Influence of constant temperature time分布曲線圖。al圖6所示,褐煤和不同溫度提質(zhì)褐煤的孔徑分布在30~300A.與褐煤相比,恒溫時(shí)間30min隨著熱解溫度的升高,提質(zhì)褐煤孔徑分布在中孔范圍內(nèi)的孔數(shù)量增多,其中孔徑為50A以下的孔數(shù)減少,50-300A范圍的孔數(shù)增多。恒溫時(shí)間一定提高熱解溫度可以使提質(zhì)褐煤的孔徑分布向孔徑相對(duì)較大的方向轉(zhuǎn)移。圖7所示,保持熱解溫度350℃不同恒溫時(shí)間下得到的提質(zhì)褐煤孔徑分布在30~300A。隨著恒溫時(shí)間的增長(zhǎng),提質(zhì)褐煤的孔徑分布向小孔范圍方向移動(dòng),孔徑為50A左右的孔先減少后增加。熱解溫度為350℃時(shí),隨著恒溫時(shí)間的增加,煤粒軟化程度的不同,煤中揮發(fā)分析出所形成的毛細(xì)孔數(shù)量不同以及揮發(fā)分析出伴隨生成的半析出態(tài)焦油的影響提質(zhì)褐煤的孔徑分布向孔徑相對(duì)較小的方向轉(zhuǎn)移恒溫時(shí)間30mi褐煤熱解溫度350℃0.0001010min250℃熱解00008300℃熱解0.000亠30min0.00006、-350℃熱解000006800004000300000000020.00000000000100D/10m圖6褐煤及提質(zhì)褐煤的孔徑分布圖7提質(zhì)褐煤的孔徑分布Fig 6 Pore diameter distribution of lignite andFig 7 Pore diameter distribution of lignite andupgrading coal at different pyrolysis conditionsupgrading coal at different homeothermic conditions3結(jié)論通過對(duì)霍林河褐煤的低溫?zé)峤庖约疤豳|(zhì)褐煤的吸附/脫附試驗(yàn),得到如下結(jié)論。1)熱解溫度和恒溫時(shí)間對(duì)褐煤的孔結(jié)構(gòu)分布影響較大,褐煤和提質(zhì)褐煤吸附等溫線均屬第Ⅲ類吸附等溫線。2)隨著熱解溫度的升高,提質(zhì)褐煤比表面積先逐漸減小隨后增大,平均孔徑和孔容先增大再減小;隨著恒溫時(shí)間的增長(zhǎng),提質(zhì)褐煤的比表面積逐漸增大,平均孔徑和孔容先減小后增大,在30min有最小值,整體呈現(xiàn)“V"型變化規(guī)律。3)褐煤及提質(zhì)褐煤的孔徑分布在30-300A,屬中孔范圍,300A以上的孔較少。不同熱解條件下,褐煤軟化程度不同,揮發(fā)分析出所形成的毛細(xì)孔數(shù)量不同以及揮發(fā)廠HH中國(guó)煤化工態(tài)焦油共同影響提質(zhì)褐煤的孔徑分布:提高熱解溫度有利于孔徑分布向較大孔CNMH間有利于孔徑分布向較小孔方向轉(zhuǎn)移。4)褐煤提質(zhì)技術(shù)主要有非蒸發(fā)脫水提質(zhì)、成型提質(zhì)、熱解提質(zhì)3類,其中國(guó)內(nèi)在成型提質(zhì)和熱解提質(zhì)第6期葉普海竽:輕度熱解提質(zhì)褐煤孔結(jié)構(gòu)研究757方面研究得較深入,逐步掌握了相關(guān)的核心技術(shù)和設(shè)備,在工業(yè)化應(yīng)用方面取得重要成果。褐煤提質(zhì)在實(shí)現(xiàn)褐煤脫水的同時(shí)有效的提髙了褐煤質(zhì)量,對(duì)于實(shí)現(xiàn)我國(guó)豐富褐煤資源的髙效綜合利用具有重要意義。參考文獻(xiàn) References[1]李培,周永剛楊建國(guó)等.蒙東褐煤脫水改質(zhì)的孔隙特性研究[J].動(dòng)力工程學(xué)報(bào),2011,31(3):176-180LI Pei, ZHOU Yong-gang, YANG Jian-guo, et al. Study on pore characteristics of dewatered east Inner Mongolia lignite[J]Jourmal of Chinese Society of Power Engineering, 2011, 31(3): 176-180[2]王亞峰.褐煤低溫?zé)峤馓匦匝芯縖J]河南化工,2011,28(8):25-27WANG Ya-feng. Study on the characteristics of lignite within low temperature pyrolysis[J]. Henan Chemical Industry, 201128(8):25-2[3] Christian Bergins. Kinetics and mechanism during mechanical thermal dewatering of lignite[J ]. Fuel, 2003, 82(3): 355-364[4]陳海旭.我國(guó)褐煤燃前脫灰脫水提質(zhì)現(xiàn)狀[J].中國(guó)煤炭,200,35(4)98-100CHEN Hai-xu. Current situation ofdeliming dehydration and improving the quality before burning[ J]. China Coal2009,35(4):98-100[5]邵俊杰褐煤提質(zhì)技術(shù)現(xiàn)狀及我國(guó)褐煤提質(zhì)技術(shù)發(fā)展趨勢(shì)初探[J]-神華科技,2009,7(2):17-22SHAO Jun-jie. The development status of lignite quality improvement technology and development trend of Chinas lignitequality improvement technology[ J]. Shenhua Science and Technology, 2009, 7(2): 17-22[6]楊慶賢,盧學(xué)棟氣體吸附理論的研究[J.應(yīng)用科學(xué)學(xué)報(bào),1998,16(2):191-19YANG Qing-xian, LU Xue-dong. a study on adsorptive theory of real gases[ J]. Joumal of Applied Sciences, 1998, 16(2)7]孟憲明煤孔隙結(jié)構(gòu)和煤對(duì)氣體吸附特性研究[D].青島:山東科技大學(xué),200MENG Xian-ming. Study on the pore structure of coals and characteristics of gases adsorption on coals[D]. Qingdao: Shan-dong University of Science and Technology[8]張占存煤的吸附特征及煤中孔隙的分布規(guī)律[J].煤礦安全,2006(9):1-3ZHANG Zhan-cun. Adsorption characteristic of coal and distribution rules of pore of coal[ J]. Safety in Coal Mines, 2006(9)[9]陳萍,唐修義低溫氮吸附法與煤中微孔隙特征的研究[J]煤炭學(xué)報(bào),2001,26(5):52-56CHEN Ping, TANG Xiu-yi. The research on the adsorption of nitrogen in low temperature and micro-pore properties in coal[J]- Journal of China Coal Society, 2001, 26(5): 52-56[10] Gulbin Gurdal, Namlk YalcIn. Pore volume and surface area of the Carboniferous coals from the Zonguldak basin(NW Turkey)and their variations with rank and maceral composition[ J]. Intemational Journal of Coal Geology, 2001,48(12): 133[1]何余生,李忠,奚紅霞,等氣固吸附等溫線的研究進(jìn)展[J]離子交換與吸附,2004,20(4):376-384HE Yu-sheng, LI Zhong, XI Hong-xia, et al. Research progress of gas-solid adsorption isotherms[ J ]. lon Exchange and Ad-sorpuon,2004,20(4):376-384[12]嚴(yán)繼明.吸附與凝聚一固體的表面與孔[M].北京:科學(xué)出版社,1986Yan Ji-ming. Adsorption and condensed-solid surface and holes[M]. Beijing: Science Press, 1986[13]袁曉紅,姚源,唐永良活性炭吸附劑的孔結(jié)構(gòu)表征[J].中國(guó)粉體技術(shù),200,6(s):190-191YUAN Xiao-hong, YAO Yuan, TANG Yong-liang. Characterization of activated carbon hole structure[ J]. China Powder Sci-ence and Technology, 2000, 6(s): 190-191[14]邱紀(jì)華.煤粉在熱分解過程中比表面積和孔隙結(jié)構(gòu)的變化[J].燃料化學(xué)學(xué)報(bào),1994,22(3):316-319QIU Ji-hua. Variation of surface area and pore structure of pulverized coal de中國(guó)煤化工 I Chemistry andTechnology,1994,2(3):316-319CNMHG[15]張雙全.煤化學(xué)[M].徐州:中國(guó)礦業(yè)大學(xué)出版社,2004ZHANG Shuang-quan. Coal chemistry[ M]. Xuzhou: China University of Mining and Technology Press, 2004758西安科技大學(xué)學(xué)報(bào)2012年P(guān)ore structure of mild pyrolysis of upgrading ligniteYE Pu-hai, ZHOU Min, LIU Gong-xinQIAN Chun-mei, YANG Xu, CHEN Heng-bao(1. Key Laboratory of Coal Processing and Eficient Utilization, Ministry of Education, School of ChemicalEngineering and Technology, China University of Mining and Technology, Xuzhou 221116China; 2. Xinjiang Tianchi Energy limited liability company, Changji 831100, China)Abstract: Based on the TGA analysis of Huolinhe lignite, experiments were performed to explore theprocess of slight pyrolysis in the tube furnace. Low-temperature nitrogen adsorption methods were usedto study the pore characteristics of the coal sample before and after pyrolysis. Influences of different ofpyrolysis temperature and constant temperature time on the coal pore structure were investigated. Theresults shows that pyrolysis temperature and constant temperature time have significant influences on thepore structure distribution, the adsorption and desorption isotherms are not coincident while the difference of raw coal is greater which indicates the upgraded coal has fewer microspores and more largerpores. Compared with the raw coal, surface area and pore volume decrease and average pore size in-creased after slight pyrolysisKey words: lignite; pyrolysis; upgrading; pore characteristic; adsorption/desorption isotherms*CorrespondingauthorYePu-hai,CandidateforM.D.,Xuzhou221116,P.R.cHina,Tel:0086-13852439846,e-mail:yphs@163.com必必必必必必必必必必必必必必必必必必必必必必必必必必必必必必必①必必必必必(上接第721頁(yè))[8 Duncan J M Chang C Y. Non-linear analysis of stress and strain in soils[ J]. Soil Mech and Found, 1970, 96(SM5): 1 629l653[9 Kondner R L. Hyperbolic stress-strain response of cohesive soils[ J]. Soil Mech and Found, 1963, 89(1): 115-143[10]黃文熙.土的彈塑性應(yīng)力應(yīng)變模型理論[J].巖土力學(xué),1979,1(2):14-37HUANG Wen-xi. Elastoplastic stress-strain model theories of soil[ J]. Rock and Soil Mechanics, 1979, 1(2): 14-37Application of voltage-sharing anchor netssupporting on"three soft compound roofwU Xin-xuan, YE Dong-sheng, wU Zhao-junShaanxi Coal Mining Co., LTD, Heyang 715306, China)Abstract: Wangcun coal mine belongs to the"three soft"compound roof, Its roadway support is a seri-ous problem that should be permanently explored. In order to solve this problem, we conduct an expement with high strength and high prestress that yielding pressure anchor nets supporting on 13503 working face, optimize yielding voltage-sharing supporting system, so as to solve the problems such as validation control the deformation of roadway wall rock, improve the quality of the supportKey words: roadway support; voltage-sharing anchor nets support中國(guó)煤化工CNMHGCorresponding author WU Xin- xuan, Senior Engineer, Xi'an 710054, P R China, Tel 0086-13891371023, E-mail: wuxinxuanl63@ 163.