秸秆与兖州煤共液化反应条件的研究

在高压反应釜内,以四氢萘为供氢溶剂,Fe2O3＋S为催化剂,研究了温度、反应时间、初始氢压、配比对兖州煤与秸秆共液化的影响。结果表明,提高反应温度,转化率、油产率增加;延长反应时间对转化率、油产率的影响较小;升高初始氢压,转化率、油产率刚开始增加,6 MPa以后增幅趋缓;在m（秸秆）∶m（兖州煤）=0.5∶9.5时,共液化的油产率为60.45%,比兖州煤单独液化的油产率提高了4.17%;在m（兖州煤）∶m（秸秆）=9.5∶0.5,440℃,8 MPa,90 min的条件下,共液化转化率和油产率达到最大,分别为83.58%和63.1%。     

溶剂抽提对兖州煤高温快速液化反应性的影响

以四氢呋喃为抽提溶剂,利用索氏提取器对兖州煤进行了抽提处理.对原煤与所得到的抽余煤进行了扫描电镜、N2吸附-脱附、热重和红外分析并进行了高温快速液化实验.通过与原煤的对比,考察了溶剂索氏抽提对煤的结构和液化反应性的影响.结果表明:抽余煤结构和热解行为均发生了明显改变;与原煤相比较,其高温快速液化的转化率有明显提高;低分子化合物对无外在活性氢来源的煤高温快速液化明显起到提供氢源的作用.     

胜利煤与秸秆共液化的研究

选用胜利褐煤和玉米秸秆为原料,在高压反应釜内,对其共液化反应性进行了研究。利用索氏抽提对液相产物进行了分离,系统地考察了反应温度、原料配比、初始氢压和反应时间对胜利煤和秸秆共液化的影响。研究结果表明:秸秆能够有效地促进胜利煤的转化,提高油产率。在反应温度420℃、初始氢压9MPa、秸秆/胜利煤质量配比=2/8和反应时间60min时,胜利煤和秸秆共液化的转化率和油产率分别为99.74%、65.30%。     

煤液化基础研究进展

综述了煤结构、煤相关模型化合物反应及煤与生物质共液化的研究进展 .着重讨论了煤结构的研究方法、煤的物理结构及煤分子结构的发展情况 ,供氢溶剂、金属及其硫化物在煤液化中的作用 ,模型化合物的分子结构和反应性的关系及模型化合物反应的动力学 ,煤与废塑料和木屑共液化等 .指出基于煤分子结构和煤液化理论研究的突破 ,可望开发出可行的煤液化工艺 ,实现煤的高附加值转化 .     

木质素加氢液化研究

在高压釜内,研究了温度、反应时间、初始氢压和搅拌速率对木质素加氢液化反应的影响。结果表明,木质素加氢液化的最佳工艺条件为:温度300℃,反应时间60 min,氢压3 MPa,搅拌速率800 r/min。在此条件下,木质素转化率与液体产率分别为71.3%与66.8%。     

高温下兖州煤焦/CO2气化反应性

在常压、温度为950 ℃～1 400 ℃范围内,以二氧化碳为气化剂,用等温热重法研究了我国兖州煤的高温气化反应性.主要考察了反应温度、热解终温和热解速率对兖州煤焦高温反应性的影响,并把兖州煤焦的高温反应性和神府煤焦的高温反应性作了比较.结果表明:随气化温度的提高,兖州煤焦反应性的总体趋势增强;快速热解焦的反应性优于慢速热解焦;热解温度对兖州煤焦反应性的影响甚微;在低温段,兖州煤焦的反应性比神府煤焦略差,但在高温段,兖州煤焦的反应性与神府煤相近.     

新疆淖毛湖煤加氢液化特性及液化产物中氢的分布规律

以新疆淖毛湖煤和四氢萘为原料,在2L高压釜中进行加氢液化实验,开展新疆淖毛湖煤直接液化过程调控研究,考查了温度、压力、时间及催化剂对氢耗、气产率、转化率、油产率和沥青类物质产率的影响规律,探讨了复杂多相体系液化产物中氢的分布规律,揭示了煤直接加氢液化反应与氢分布规律的内在联系.结果表明:在420℃,15MPa和60min的反应条件下,淖毛湖煤的转化率为94%,油产率为65%,是适宜直接液化的优良煤种;氢较均匀地分布在淖毛湖煤加氢液化的轻质产物(水、150℃馏分油、150℃～260℃馏分油和260℃～350℃馏分油)中,在350℃重质馏分油中分布最高,接近30%;氢在液化产物中的分布与加氢液化反应效果呈现出正相关特征.     

铁系催化剂对煤高温快速液化的影响

以兖州煤为研究对象,采用微型反应釜研究了两种铁系催化剂对煤高温快速液化的影响.结果表明,担载Fe2S3的催化剂和高分散铁系催化剂对煤的热解行为影响较小;担载Fe2S3催化剂促进了氢气参与反应和煤液化产物向轻质化转化,在优秀和足量的供氢溶剂条件下,溶剂的供氢速度明显优于氢气转换的供氢速度,催化剂的作用不明显;对比添加高分散铁系催化剂并加助剂S和添加Fe2S3催化剂的煤高温快速液化,发现元素S的作用与S和主催化剂铁的结合形态有关.     

超声波预处理对煤-油临氢共炼的影响

在预设的超声条件下对不同煤-油共炼原料进行预处理,并在相同的反应条件下使用实验室自制的铁系催化剂进行煤-油共炼反应,考察煤液化率的变化,对液体产物进行元素和馏程分析以及对固体产物进行工业四组分分析,确定超声波预处理对煤-油临氢共炼的影响.结果表明:经过超声波预处理后,共炼原料结构发生改变,分别对油浆及使用安徽煤与油浆所配油煤浆进行超声处理,再进行共炼反应,安徽煤的液化率分别提高9.85%和12.42%;分别对煤焦油及对使用安徽煤与煤焦油所配油煤浆进行超声处理,再进行共炼反应,安徽煤的液化率分别提高7.99%和18.65%,固体产物的灰分、挥发分降低,固定碳含量增加,质量有所提高;液体产物的馏程分布基本没有改变.达到了在提高煤液化率的同时、保证共炼产物质量不变的目的.     

煤与生物质共液化研究进展

重点介绍了木质素结构及其液化、煤与木质素共液化工艺及研究进展。同时还介绍了煤与其它生物质的共液化情况,对煤与生物质共液化研究发展方向以及目前面临的一些问题作了简要叙述。     

Viscosity variations of coal-oil slurry under high temperature and high pressure during heating process

Heating coal-oil slurry (COSL) is an important step in direct coal liquefaction. Some physical and chemical properties of COSL including its viscosity will change during heating. A rotary viscometer was self-designed to measure the viscosity of COSL under high pressure and temperature. Three kinds of coal, which are Yanzhou coal (middle rank and caking), Shenhua coal (low rank and non-caking) and Shengli coal (brown coal), were mixed with anthracene oil to prepare the COSL. The COSL from Yanzhou, Shenhua and Shengli at the same experimental conditions showed different viscosity variations under high hydrogen pressure during heating. Yanzhou COSL had a higher viscosity peak, while Shenhua COSL had two small viscosity peaks and in the case of Shengli COSL, no viscosity peak was present under a high hydrogen pressure during the whole heating process. The coal nature is the important factor of viscosity variations of COSL. The higher the coal rank, the more caking coal is present, and the more obvious the viscosity variations of the COSL are.     

Additive effect of tyre constituents on the hydrogenolyses of coal liquefaction residue

A numerous amount of waste tyre is landfilled or dumped all over the world, which causes environmental problems. The coal liquefaction residue (CLR) produced in 30% yield through the process supporting unit of the NEDOL coal liquefaction process. As one of the effective method for processing both CLR and waste tyre, simultaneous hydrogenolyses of these materials was carried out. The synergistic effects to upgrading, such as the increase of oil yield and the decrease of asphaltene yield, were appeared on the hydrogenolyses. However, the interaction between tyre and CLR to synergistic effects was not clarified. In this study, the effects of hydrogen donatable solvent (tetralin) and pressurized gas on the hydrogenolyses of CLR and tyre constituents are discussed. As a result, it was clarified that both tetralin and the pressurized H₂ gas were necessary for the simultaneous hydrogenolyses of CLR and tyre. The hydrogen shuttling from H₂ gas and tetralin was enhanced by the aromatic compounds derived from tyre rubber constituents (styrene-butadiene rubber and natural rubber). The hydrogenation of the heavy oil constituent in CLR was enhanced by carbon black and the inorganic constituents in tyre, such as zinc oxide and sulfur. Accordingly, the synergistic effects on the simultaneous hydrogenolyses of CLR and tyre were appeared because the hydrogen shuttling occurred by the aromatics from tyre rubber constituents, and the hydrogenation was enhanced by carbon black and the inorganic constituents in tyre.     

氢气在无催化煤液化中的反应机理

采用平衡液相取样法气体溶解度测定装置测定了氢气在萘中的溶解规律,并采用间歇式微型反应釜研究了氢气在无催化煤液化中的反应机理.结果表明:1)氢气在萘中的溶解随着温度和压力的升高而增加,溶解速率先快后慢,在5min时达到最大溶解量的76.21%左右,直到30min达到平衡;2)在萘溶剂的无催化煤液化反应中,氢气的溶解不是控制步骤,溶解氢参与液化反应的速度才是控制步骤;3)在较短时间的萘溶剂无催化煤液化时,氢气在萘溶剂中的预溶解提高了无催化煤液化的总转化率,其主要原因是部分预溶氢提前活化,使得煤液化反应初期活性氢增加;4)在较长时间的萘溶剂无催化煤液化时,预溶氢对总转化率的提高很小,但促进了液化产物的进一步裂解加氢轻质化.     

兖州煤与大庆减压渣油共处理的研究

采用大庆减压渣油与兖州煤共处理，详细考察了共处理过程对煤液化转化率的影响，并借助棒状薄层色谱（ＴＬＣ－ＦＩＤ）通过对原料组成的考察，论证了大庆减压渣油在共处理过程的作用。结果表明，大庆减压渣油是煤液化的不良溶剂，当它与兖州煤共处理时，能降低兖州煤的液化能力。共处理过程中延长反应时间与升高反应温度有类似的效果，均使甲苯不溶物－前沥青烯含量降低，促进煤液化产物向小分子方向转化。在共处理中大庆减压渣油在     

微波条件下两种煤丙酮萃取物的GC/MS分析

以丙酮作为溶剂,在微波辐射条件下对兖州煤和神府煤进行萃取,并利用气相色谱/质谱联用(GC/MS)技术对萃取物进行分析.结果表明:萃取物主要由芳烃和脂肪烃组成.在兖州煤的萃取物中芳烃主要是茶系化合物,而在神府煤的萃取物中检测出的芳烃以菲系为主;在兖州煤的萃取物中检测出多种异构烷烃,而在神府煤中只检测出一种异构烷烃.     

Quantitative study on cross-linking reactions of oxygen groups during liquefaction of lignite by a new model system

Cross-linking reactions (CLR) of oxygen groups during liquefaction of lignite were quantitatively studied by a new model system. Chinese Yitai lignite (YT) was first oxidized by nitric acid at 70 °C and about 98% of the oxidized sample could be dissolved in tetrahydrofuran (THF) at room temperature. Then benzyl alcohol, PhCH₂OH (BA), as a model compound was added into the oxidized coal, also acted as solvent in the subsequent liquefaction. Temperature-programmed reactions (TPR) at liquefaction conditions under hydrogen atmosphere were performed to evaluate the CLR by quantitative analysis of THF-insoluble solid products (THFI) after reaction. Extensive CLR were observed even under high pressure of H₂ at 200-400 °C, and more than 51.7% and 81.2% of the THFS fraction was converted into the THFI at 300 °C with tetralin (TET) and BA as solvent, respectively. The THFI fraction was almost solely caused by the CLR, which makes it possible to quantitatively study the CLR by analyzing the amount of the cross-linked solid products (CSP). The pyrolysis behaviours of CSP and oxidized coal were examined by TG. Other model compounds containing oxygen-functional groups (alcohol, phenol, carboxyl, carbonyl and ether groups) can also be used in this model system to study CLR of oxygen groups in low-rank coals.     

Effects of ion-exchanged calcium, barium and magnesium on cross-linking reactions during direct liquefaction of oxidized lignite

In this work the influences of alkaline earth metals on cross-linking reactions (CLRs) during direct liquefaction of lignite were investigated. The oxidized lignite, which has been proved to be appropriate for quantitatively examine the extent of CLR during direct liquefaction, was used as a model coal to study the effects of ion-exchanged calcium, barium and magnesium on CLR during direct liquefaction of the oxidized lignite. The amounts of tetrahydrofuran (THF) insoluble solid products after liquefaction were used to quantitatively evaluate the CLR during liquefaction of the ion-exchanged coal. The results show that the oxidized coal is appropriate to quantitatively examine the extent of CLR and the targeted ions are exchanged to the oxidized coal in the form of highly-dispersed ion. The ion-exchanged Mg^2 + suppresses the CLR during direct liquefaction of coal at both low and high temperature. However, the exchanged Ca^2 + always promotes the CLR at the selected temperatures. While the exchanged Ba^2 + promotes the CLR at low temperature, but suppresses it at high temperature.     

氢气在煤液化初始高活性阶段的作用机理

采用GJ-2型共振搅拌反应釜,首先研究了一定条件下煤液化转化率随时间的变化关系.结果表明,煤液化反应过程中存在着初始高活性反应阶段,而且煤在该阶段完成了绝大部分液化反应;接着研究了氢气在煤液化初始高活性阶段的作用机理.结果如下:1)在无催化液化条件下,氢气在煤液化初始高活性阶段几乎不参与煤液化反应;2)煤液化初始高活性阶段氢气能够快速溶解于煤液化溶剂中,因此氢气的溶解过程不是其未有效参与煤液化反应的主要原因;3)在煤液化初始高活性阶段添加高分散性铁系催化剂和助剂硫,氢气在催化剂作用下参与了煤液化反应,进而使液化总转化率提高7%以上.