神木烟煤与桦甸油页岩的共热解特性

采用热重分析仪和固定床反应器研究了神木烟煤和桦甸油页岩的混合共热解特性及协同作用机制. 结果表明,神木煤与桦甸油页岩混合共热解的失重率高于计算值,表明二者在热解和挥发分逸出过程中存在相互作用,促进了挥发分释放,减少了半焦生成. 煤与油页岩的协同作用可增加热解油收率、降低半焦和水收率. 油页岩与煤质量比为1:1时,所得油收率最高,为9.84%,比计算值提高8.8%. 共热解有助于提高轻质油含量和收率,油页岩与煤质量比为1:4时,轻质油含量超过80%,收率约为7.5%,比计算值分别提高了8%和11.2%,表明添加少量油页岩可明显提高热解油品质. 共热解过程中油页岩产生的富氢组分及自由基能抑制煤热解产生的芳香族化合物的聚合反应,促进芳烃向产物油转化,提高热解油的收率和品质.     

低阶煤与玉米芯低温共热解的产物特性分析

采用低温干馏装置对不同玉米芯加入量的褐煤/玉米芯混合物进行低温共热解实验。结果表明：当玉米芯加入量为30%时,焦油产率最大为11.70%,比褐煤单独热解提高了53.75%。随着玉米芯的加入量增加,热解气中CO、CH₄和H₂含量逐渐增大。对热解焦油进行GC-MS检测,发现添加30%玉米芯后脂肪族质量分数从褐煤单独热解的24%提高到了30.67%,酚类质量分数从6.29%提高到了18.49%,杂原子质量分数从29.75%降低到了13.33%,一定程度上实现了焦油的轻质化和高品质化。对热解半焦进行SEM、比表面积分析和热值测定,发现共热解半焦表面变粗糙,孔隙结构得到改善,热值明显高于褐煤单独热解半焦热值。     

生物质和煤共热解特性及催化剂对热解的影响

为研究生物质和煤程序升温共热解特性及相互作用,利用热天平和管式炉反应器对白松木屑和五彩湾烟煤的共热解特性及催化剂对生物质和煤共热解的影响进行了研究,并考察了共热解半焦的孔结构特性。结果表明：不同比例的生物质和煤在共热解过程中,两者基本保持了各自的热解特性,由于生物质和煤的主要热解阶段温度相差较大,共热解过程中没有发生明显的协同作用。生物质和煤共热解半焦产率实验值大于计算值,当生物质质量分数从75%减少至25%时,半焦产率实验值与计算值之间的差值从0.81个百分点增加到1.07个百分点。橄榄石和载镍橄榄石（NiO/olivine）的添加促进了共热解反应发生的深度。载镍橄榄石催化剂添加（原料和催化剂质量比1：1）的条件下,共热解碳转化率提高了0.5%~5.1%,随着混合物中生物质比例的增加,催化剂的催化效果更加明显。     

温度梯度与产物流动对先锋褐煤热解产物分布的影响

通过两段固定床反应器分离了煤热解和二次反应过程,模拟了传统外热式固定床反应器和外热式内构件固定床反应器内挥发性热解产物流动与固相反应颗粒间的相互作用,研究了不同温度的半焦对先锋褐煤热解产物分布和品质的影响。结果表明：当半焦的温度在500～900℃时,焦油发生剧烈的二次反应,热解气收率增加,焦油收率大幅下降,H/C同时大量降低且均低于空白样,油品质下降;在100～400℃半焦作用下,焦油发生轻微的二次反应,热解气收率略微增加,焦油收率缓慢下降,但H/C均高于空白样,油品质提升。该结果验证内构件外热式固定床反应器热解产生的焦油具有更高的收率及品质。     

半焦基催化剂裂解煤热解产物提高油气品质

利用上段热解下段催化的两段固定床反应器,针对府谷煤研究了半焦和半焦负载Co催化剂对煤热解产物的催化裂解效果。结果表明,半焦和半焦负载钴对热解产物催化裂解后,热解气收率增加,焦油收率降低,但焦油中沸点低于360℃的轻质组分含量提高,轻质焦油收率基本保持不变或略有增加。与煤在600℃直接热解相比,在热解和催化温度均为600℃,采用煤样质量20%的半焦为催化剂时焦油中轻质组分质量含量提高了约25%,轻质组分收率基本不变,热解气体积收率增加了31.2%;在热解温度600℃,催化温度500℃时,采用煤样质量5%的半焦负载钴催化剂,焦油中轻质组分质量收率和含量分别提高了约8.8%和28.8%,热解气体积收率增加了21.5%。煤热解产物的二次催化裂解的总体效果是将焦油中重质组分转化为轻质焦油和热解气。     

褐煤与大豆荚共热解的产物特性分析

利用自制的低温热解装置研究褐煤与大豆荚共热解的产物特性,考察大豆荚掺混比和催化剂Fe₂O₃对热解产物特性的影响。通过FT-IR、GC-MS、SEM-EDX和UV-vis分析共热解产物的性质,并将半焦用于亚甲基蓝吸附实验。研究结果表明：掺混比30%时,共热解焦油的产率达到最大值11.98%,比煤焦油产率增加44.86%,与计算值的正偏差最大（0.8%）,同时,大豆荚的添加有促进焦油生成的协同作用。大豆荚的添加有利于共热解焦油中含氧杂环的断裂,使共热解焦油中直链烷烃增多,芳香族化合物减少,使重质组分转化为轻质组分,从而提高焦油品质;同时,大豆荚的添加使共热解半焦的含氧基团增加,微观形貌变粗糙。而Fe₂O₃的加入使共热解焦油中酚、醇类物质增加;加Fe₂O₃共热解半焦的褶皱更加明显。共热解半焦对亚甲基蓝的吸附率为33.62%,比煤半焦的吸附率提高8.84%,加Fe₂O₃共热解半焦的吸附率为55.57%,比共热解半焦提高65.29%。     

生物质与催化裂化油浆共热解协同作用研究

基于生物质焦油氧含量高、品质差的缺陷,本文提出将生物质与重油共转化利用的方法。以催化裂化油浆（FCC）、稻壳（RH）、木屑（PS）为原料,通过低温固定床热解实验对其共热解产物分布进行了研究。结果表明,在FCC的供氢作用下,共热解有利于焦油中含氧化合物的脱除,随着生物质比例增加,反应过程中脱羧基、脱羰基反应减弱,脱羟基反应增强,产物中CO、CO₂产率较计算值增加幅度减小,水的产率较计算值逐渐增大。焦油中烃类物质增加,其中芳香烃以二元环和四元环增加为主,脂肪烃中以C₁₃~C₂₀增加为主。整体上,共热解过程促进了半焦产率的增加,焦油产率虽无明显改变但品质得到了显著提升。     

生物质三组分二元混合热解特性研究

采用TG-FTIR-MS研究了生物质三组分二元混合热解过程的失重特性和小分子气体逸出规律。结果表明二元混合组分热解过程降低了热解反应开始温度。纤维素与半纤维素混合热解过程热解反应受到抑制,热解失重率降低,H₂、CH₄和H₂O产量减小,CO和CO₂产量增加。木质素和半纤维素在混合热解过程中存在协同效应,促进热解反应进行,H₂产量增加,然而其他小分子气体产物的生成被抑制,协同效应的效果更有利于可冷凝挥发分产物生成,这种效应随着半纤维素比例增大而减弱。半纤维素和纤维素在整个热解过程表现出相互抑制的效果,其小分子气体产物产量减小,但随着纤维素比例增大,影响减弱。     

生物质与催化裂化油浆共热解协同作用研究

基于生物质焦油氧含量高、品质差的缺陷,本文提出将生物质与重油共转化利用的方法。以催化裂化油浆（FCC）、稻壳（RH）、木屑（PS）为原料,通过低温固定床热解实验对其共热解产物分布进行了研究。结果表明,在FCC的供氢作用下,共热解有利于焦油中含氧化合物的脱除,随着生物质比例增加,反应过程中脱羧基、脱羰基反应减弱,脱羟基反应增强,产物中CO、CO₂产率较计算值增加幅度减小,水的产率较计算值逐渐增大。焦油中烃类物质增加,其中芳香烃以二元环和四元环增加为主,脂肪烃中以C₁₃~C₂₀增加为主。整体上,共热解过程促进了半焦产率的增加,焦油产率虽无明显改变但品质得到了显著提升。     

Co-pyrolysis of pine cone with synthetic polymers

Biomass from pine cone (Pinus pinea L.) was co-pyrolyzed with synthetic polymers (PE, PP and PS) in order to investigate the effect of biomass and plastic nature on the product yields and quality of pyrolysis oils and chars. The pyrolysis temperature was of 500 °C and it was selected based on results from thermogravimetric analysis of the studied samples. Co-pyrolysis products namely gases, aqueous and tar fraction coming from biomass, oils from synthetic polymers and residual char were collected and analyzed. Due to the synergistic effect in the pyrolysis of the biomass/polymer mixtures, higher amounts of liquid products were obtained compared to theoretical ones. To investigate the effect of biomass content on the co-pyrolysis, the co-pyrolysis of pure cellulose as model natural polymer for biomass with polymer mixture was also carried out. In the presence of cellulose, degradation reaction leading to more gas formation and less char yield was more advanced than in the case of co-pyrolysis with pine cone. Co-pyrolysis gave polar oxygenated compounds distributed between tar and aqueous phase and hydrocarbon oils with composition depending on the type of synthetic polyolefin. Co-pyrolysis chars had higher calorific values compared to pyrolysis of biomass alone.     

热解条件对西湾煤与秸秆流化床加压共热解的影响

在流化床加压热解装置中考察温度、压力、气氛和生物质掺混比等条件对西湾煤与秸秆共热解特性的影响,结果表明:在600℃,0.3 MPa,100%N₂气氛条件下,随着生物质掺混比增加,共热解油产率先增加后降低,实验值均大于计算值;当生物质掺混比为30%(质量分数)时,共热解油的实验值达到最大(16.90%),高于计算值(13.05%);热解压力由常压升至1.0 MPa时,受高氢分压作用下较多的氢分子参与自由基的加氢饱和作用,共热解油产率先增加后降低,在0.3 MPa时共热解油产率达到最大(17.90%);100%(体积分数,下同)N₂,100%CO₂和50%CO₂+50%H₂气氛下的共热解油产率分别为16.73%,16.55%和16.07%;与焦油相比,共热解油的密度变化不大,在元素中碳的质量分数由79.32%降低至71.80%,硫的质量分数由0.60%降低至0.31%,n(H)/n(C)增加;共热解油中脂肪烃、芳香烃和含氧化合物的质量分数降低,酚类组分的质量分数增加,三环及以上的多环产物裂解为小分子化合物,油品质量得到改善。     

Pyrolysis and co-pyrolysis of Laminaria japonica and polypropylene over mesoporous Al-SBA-15 catalyst

The catalytic co-pyrolysis of a seaweed biomass, Laminaria japonica, and a typical polymer material, polypropylene, was studied for the first time. A mesoporous material Al-SBA-15 was used as a catalyst. Pyrolysis experiments were conducted using a fixed-bed reactor and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). BET surface area, N₂ adsorption-desorption isotherms, and NH₃ temperature programmed desorption were measured to examine the catalyst characteristics. When only L. japonica was pyrolyzed, catalytic reforming slightly increased the gas yield and decreased the oil yield. The H₂O content in bio-oil was increased by catalytic reforming from 42.03 to 50.32 wt% due to the dehydration reaction occurring on the acid sites inside the large pores of Al-SBA-15. Acids, oxygenates, mono-aromatics, poly aromatic hydrocarbons, and phenolics were the main components of the bio-oil obtained from the pyrolysis of L. japonica. Upon catalytic reforming over Al-SBA-15, the main oxygenate species 1,4-anhydro-d-galactitol and 1,5-anhydro-d-manitol were completely removed. When L. japonica was co-pyrolyzed with polypropylene, the H₂O content in bio-oil was decreased dramatically (8.93 wt% in the case of catalytic co-pyrolysis), contributing to the improvement of the oil quality. A huge increase in the content of gasoline-range and diesel-range hydrocarbons in bio-oil was the most remarkable change that resulted from the co-pyrolysis with polypropylene, suggesting its potential as a transport fuel. The content of mono-aromatics with high economic value was also increased significantly by catalytic co-pyrolysis.     

石脑油和轻烃资源裂解方式优选研究

由于我国轻烃资源缺乏,而石脑油资源相对丰富,考虑将其掺入石脑油进行共裂解。在实验室裂解装置上对油田轻烃、拔头油的分组裂解以及与石脑油共裂解的产物收率变化进行了研究,得出油田轻烃、拔头油的分组裂解优于与石脑油共裂解,因此探讨了拔头油与油田轻烃共裂解的可行性,提出在原料短缺的情况下,可根据"性质相近"的原则进行共裂解,即可将油田轻烃与拔头油掺混进行共裂解。同时在工业裂解炉上进行了拔头油与石脑油共裂解标定试验,得出的结论与实验室结论一致。     

Liquefaction of cellulosic wastes: III. Production,characterization and evaluation of pyrolytic oils

Liquefaction of municipal solid wastes has been achieved in an atmosphere of hydrogen gas and in the presence of boric acid which catalyzes the pyrolysis reaction. Two petroleum distillates, namely gas oil and residual fuel oil, were used as carrier media of solid refuse. The yield of pyrolytic oil was studied as a function of different operational conditions (temperature, pressure of hydrogen, carrier oil medium and concentration of boric acid). Hydrocarbon constituents of the oil mixtures, produced by liquefaction of cellulosic wastes slurried in fuel oil, were investigated by means of gas chromatography. It was found that the oil mixture, obtained at optimum reaction conditions, showed pronounced occurrence of low hydrocarbons in the range C₃-C₁₅ as compared with the original fuel oil and the oil resulting from the pyrolysis of carrier oil without solid refuse. The residual pyrolytic char exhibited catalytic activity towards hydrocracking. It was suggested that the activity of char is due to the presence of transition metals as evidenced by an electron dispersion system (EDS). The hydrocracking activity of char seemed to be dependent on the operational conditions of the liquefaction. Multiple analytical parameters including API gravity, calorific value, total acid number and wt% of residue over 450°C were used to evaluate the oil mixtures produced as a petroleum crude oil. Carrier oils, particularly fuel oil, seemed to be highly modified in the course of the pyrolysis process. Also, the oil mixtures produced were distinguished from the original carrier oils by a considerably higher acidity due to association with oxygenated compounds which could be derived from cellulose macromolecules.     

强粘结性煤与有机废弃物共热解的研究

用处理量为1kg/h的回转炉作为强粘结性煤分别与生物质、废橡胶、废塑料共热解的反应器,研究了热解温度对各产品产率和煤气性质的影响,以及添加有机废弃物对焦炭光学组织的影响。结果表明：热解过程中有机废弃物能阻止煤粒之间发生粘结,得到粒状焦炭。焦油的生成率和裂解率随热解温度的变化可分别用正态分布函数和韦布尔分布函数模拟。锯末对焦炭中光学各向异性组织的形成和发展有阻碍作用,而废橡胶轮胎和废聚氯乙烯塑料对其有促进作用。     

低变质煤与塑料微波共热解研究

进行了微波加热条件下陕北孙家岔低变质煤与塑料共热解的实验研究.结果表明:随着塑料添加比例的增大,兰炭产率逐渐降低,焦油产率明显提高.当塑料加入量为10%时,焦油产率可达到17%,同时煤气中H2,CO和CH4的含量显著增加,分别可达到44.21%,18.75%和21.97%.塑料的加入有利于提高焦油的回收率,优化热解煤气成分,对煤气的进一步综合利用具有重要意义.     

木屑与煤慢速共热解产物特性研究

采用TG-FTIR联用的分析方法对木屑与煤共热解产物进行分析,结果发现,木屑与煤共热解产物不是两者单独热解的简单叠加,而是木屑与煤协同反应相互促进或抑制的结果。煤化程度越高木屑与煤共热解过程中CO和CH₄的产率越多,CO₂的产率越少,液体和固体产物越多。木屑与煤掺混比例对于共热解产物的影响规律性不是非常明显,对于CO和CH₄,掺混比例5:5时产率最低;CO₂在共热解温度<500 ℃时,掺混比例5:5时产率最高,而在共热解温度>500 ℃时,随着煤的掺混比例的增加产率逐渐减小。木屑与褐煤的共热解固体产率随着掺混比例的增加逐渐增大,木屑与无烟煤的共热解固体产率正好相反。     

间热径向流反应器料层厚度对煤热解特性的影响

考察了方形径向流固定床煤热解反应器中变化煤层厚度对料层升温速度及煤热解产物分布特性的影响。随着料层厚度增加,导致煤热解反应要求的时间增长,热解水和气的产率相应增加,焦油和半焦收率逐渐降低,但焦油中轻质组分(沸点低于360℃组分)含量呈升高趋势,半焦和煤气热值稍许降低。如,加热壁温度900℃、从45 mm至105 mm增加煤料层厚度时,焦油产率从7.17%(质量,下同)下降到6.26% (相对干基煤),但焦油中的轻焦油组分含量则从67%升至72.7%,半焦产率由80.0%降至77.0%,热解水和煤气产率分别由6.96%和5.91%增至8.85%和7.90%,煤气热值则由24348.5 kJ·m^-3下降至20649.2 kJ·m^-3。所得半焦的热值径向上由高温侧向低温侧逐渐降低,煤料层越厚、热值降幅越大,而相同煤料层厚度处与加热壁平行的同一轴向平面上的半焦热值基本相同。针对研究的反应器,气相热解产物在反应器内沿径向(横向)由高温料层区向低温料层区流动。在该过程中伴随着热解产物对远离加热壁的低温煤料的传热、热解生成重质组分的冷凝和在煤/半焦颗粒表面的吸附截留,进而在低温料层进一步升高温度时发生二次裂解等物理化学过程。反应器内煤层厚度越大,上述各种伴随的物化作用越显著,从而明显影响煤料层的升温及热解特性。     

Co-pyrolysis of bituminous coal and biomass in a pressured fluidized bed

An experimental study on co-pyrolysis of bituminous coal and biomass was performed in a pressured fluidized bed reactor. The blend ratio of biomass in the mixture was varied between 0 and 100 wt%, and the temperature was over a range of 550–650 °C under 1.0 MPa pressure with different atmospheres. On the basis of the individual pyrolysis behavior of bituminous coal and biomass, the influences of the biomass blending ratio, temperature, pressure and atmosphere on the product distribution were investigated. The results indicated that there existed a synergetic effect in the co-pyrolysis of bituminous coal and biomass in this pressured fluidized bed reactor, especially when the condition of bituminous coal and biomass blend ratio of 70:30(w/w), 600 °C, and 0.3 MPa was applied. The addition of biomass influenced the tar and char yields and gas and tar composition during co-pyrolysis. The tar yields were higher than the calculated values from individual pyrolysis of each fuel, and consequently the char yields were lower.The experimental results showed that the composition of the gaseous products was not in accordance with those of their individual fuel. The improvement of composition in tar also indicated synergistic effect in the co-pyrolysis.     

固定床烟煤与木屑共热解的协同反应性研究

在自制的固定床反应装置上对木屑和烟煤以及两者的混合物进行了热解特性研究,考察了木屑与烟煤在不同掺混比例和热解终温下的共热解反应特性。研究结果表明:协同作用发生的程度与热解反应条件有关,烟煤与木屑共热解的协同反应性不仅体现在气、液产物收率方面,同时对气体组成也有显著影响;因木屑灰分中的碱金属化合物对热解焦油的催化裂解作用,使得共热解反应在较高热解终温和较低木屑掺混比条件下表现出更为显著的协同作用;在木屑掺混比(木屑质量分数)为25%、终温540℃条件下,热解气产率的协同值达到22.6%,焦油产率协同值为-27.3%;H自由基与烟煤热解产生的自由基结合成CH4等烃类气体或转移到焦油组分,是一种重要的协同作用机理。