Effect of equivalence ratio on gas distribution and performance parameters in air-gasification of asphaltene: A model based on Artificial Neural Network (ANN)

Air-gasification of asphaltene was carried out in a bench scale fluidized bed. A neural network model was also developed to study the influence of equivalence ratio (ER) on gas distribution, lower caloric value (LHV) of producer gas, and performance indicators (char conversion and cold gas efficiencies). The contents of CO and H₂ were initially increased from 53.2 to 55.4?vol% and 35.4 to 37.6?vol% as ER increased to 0.35, and then decreased to 43.3?vol% and 27.7?vol% at ER of 0.5, respectively. The results also indicated that the LHV of the produced syngas was significantly decreased with ER increasing because of more oxidation reactions at higher ERs.     

流化床内松木屑气化过程的MP-PIC数值模拟

基于多相质点网格(MP-PIC)方法建立了三维流化床内的生物质气化反应模型,考虑蒸发、挥发分析出以及均相、非均相反应等子模块,研究了松木屑在气-固强非线性耦合作用下的空间分布特性和高温热传递过程中的热物性分布规律,探究了不同的空气当量比(ER)、蒸汽生物质比(SBR)、气化温度对气化性能和气相热物性的影响规律。结果表明：可燃气体和焦炭的氧化反应促使气相温度升高,而低温蒸汽将自由空域的温度降低至约900 K;ER的增加提升了炉内的气化温度,减小了气体密度和比热容,然而过量的空气会降低气化性能和炉内温度;SBR的增大稀释了气化产物浓度;增加气化温度提升了H₂产率,但抑制了C₂H₄的生成。     

中药渣双回路循环流化床气化试验

中药渣是中药材煎煮后的残余物,其热解气化是中药渣类生物质处理应用的重要选择方向。为此,采用带有二级返料装置的循环流化床,对杞菊地黄丸药渣进行了气化试验。以200 ℃热空气为气化剂,研究了二级返料装置开启前后空气当量比（ER）对气化特性的影响,结果表明：①随着（ER）的增大,气化炉内温度升高,燃气热值和燃气中焦油含量降低,气化效率先增大后减小;②二级返料装置闭合时,较好的ER取值范围为0.24~0.30、燃气热值为5 100~5 800 kJ/m³、气化效率为71%~74%;③二级返料装置开启时,理想的ER取值范围为0.26~0.30、燃气热值为5 400~5 900 kJ/m³、气化效率为76%~78%。在二级返料装置开启状态下研究了水蒸气配比S/B对气化过程的影响,结果表明：①空气当量比为0.28时,随着S/B的增大,气化炉内温度逐渐降低,燃气中焦油含量升高,燃气热值先增加后减小,当S/B为0.4时燃气热值取得最大值（6 200 kJ/m³）;②在相同ER条件下,二级返料装置开启状态下燃气热值及气化效率均高于闭合状态。该研究成果可以为中药渣废弃物的高效清洁利用提供参考。     

Management of waste lubricant oil (WLO): WLO-to-energy through gasification process

Possibility of synthesis gas (syngas) production from waste lubricant oil (WLO) through gasification process has been investigated. The objective of this work is to develop a comprehensive model to simulate WLO gasification using Aspen Plus simulator. The model was based on Gibbs free energy minimization and validated against the published data. Increase in ER results in CO, H₂, and CH₄ reduction and CO₂ enhancement due to partial oxidation of H₂ and CO. Since the standard chemical exergy and lower caloric value of H₂ is lower than that of CO and both of values are not considerable for CO₂, with increasing SFR (steam-to-fuel ratio) from 0.25 to 1.25, EE (exergy efficiency) and GE (gasification efficiency) were decreased.     

Kinetic modeling of crude oil gasification for hydrogen production with in situ CO2 capture

Steam gasification process in the presence of CaO is an efficient method to convert carbon-based fuels, producing a gas with low concentration of CO₂ and high hydrogen yield. In the present work, an unsteady-state, kinetic model of crude oil gasification was developed for prediction of gas composition and performance parameters. The effects of key operating parameters including [H₂O]/[C] and [CaO]/[C] on hydrogen yield and CO₂ capture ratio (CCR) were studied. The results showed that the CCR increased with increasing [CaO]/[C] from 0.1 to 0.7 (mg/mg) and then decreased, probably due to the reversal of exothermic carbonation reaction by Le Chatelier's principle. In spite of [CaO]/[C], CCR improved continuously with increasing [H₂O]/[C] probably due to a significant improvement in the endothermic nature of the process by increasing [H₂O]/[C].     

Effect of asphaltene,carbonate, and clay mineral contents on water cut determination in water–oil emulsions

The role of asphaltene, carbonate, and clay contents on the stability of water–oil emulsions and water cut determination was evaluated via both IR analysis and physicochemical properties of the tested mixtures. To study the effect of asphaltene addition, 10 emulsions were prepared. The first five emulsions contained different water cuts from 10 to 50 wt.%, and constant asphaltene ratio of 0.2 wt.% while the second five specimens contained different asphaltene ratios of 0.1, 0.3, 0.5, and 0.7 wt.%.To study the effect of clay types, 10 water-in-oil emulsions with different clay types (kaolinite and bentonite) and different water cuts from 10–50 wt.% were tested. To study the effect of clay ratios, six water-in-oil emulsions with different clay types and ratios of 2, 4, and 8 wt.% were prepared. The effect of carbonate type was studied with the use of calcite (CaCO₃), magnesite (MgCO₃), and dolomite (CaMg (CO₃)₂), and different water cuts from 10–50 wt.% The effect of different carbonate ratios of 1, 3, and 5 wt.% was also studied.Relationships between water cut, major functional groups, and mixture physicochemical properties were developed. Therefore, for a known property, water cut could be predicted.     

Change of asphaltene and resin properties after catalytic aquathermolysis

Resin and asphaltene were separated from Liaohe heavy oil. Catalytic aquathermolysis of asphaltene and resin was investigated by using water soluble catalysts （NiSO4 and FeSO4） and oil soluble catalysts （nickel naphthenate and iron naphthenate）. Before and after aquathermolysis, the properties of the resin and asphaltene was compared by means of ultimate analysis, vapor pressure osmometer （VPO） average molecular weight, X-ray diffraction （XRD）,^13C and ^1H nuclear magnetic resonance （NMR）. The conversion sequence was as follows： No-catalyst〈NiSO4〈FeSO4〈nickel naphthenate〈iron naphthenate. In the presence of catalysts, the amount of H2 and CO increased significantly, while H2S in the gas product decreased. The molecular weight of asphaltene and resin increased after reaction without catalyst. But the catalysts restrained this trend. The H/C ratio of asphaltene and resin decreased after reaction. From the results of average structural parameters and molecular weight, it was found that asphaltene and resin were partly aggregated after aquathermolysis.     

串行流化床生物质气化动力学模拟

生物质是一种清洁、可再生能源,来源广泛。串行流化床气化工艺将生物质气化和燃烧过程分离,具有气化温度较低和合成气浓度高等优点,是国内外学者进行生物质能源利用研究的热点之一。为模拟其气化过程,针对松木和玉米秸秆这2种生物质原料,以水蒸气为气化介质,结合气化反应动力学方程,利用Aspen Plus系统(V7.2)对串行流化床生物质气化过程进行了动力学模拟,考察了进料水蒸气与生物质质量比(S/B)和气化温度对气化干气组成和产率的影响。模拟结果表明:①S/B值的变化、气化湿度的变化对松木和玉米秸秆气化所得干气组成及产率的影响趋势是一致的,但随着S/B增加,松木和玉米秸秆气化所得干气产率增加,CO_2和H_2含量升高,CO含量降低;②随着气化温度的升高,干气中H_2和CO_2含量逐渐降低,CO含量和干气产率增加;③在相同研究条件下,松木气化所得干气中的H_2含量与玉米秸秆气化相当,但产率优于玉米秸秆气化的产率。     

Aspen Plus simulation of steam-gasification of different crude oils: A detailed comparison

The gasification process is being developed to obtain environmentally clean and efficient syngas from solid (coal, biomass, and municipal solid waste) or liquid (heavy oil and waste lubricant oil) fuels for power generation. An Aspen Plus model of crude oil gasification in presence of steam as a gasifying agent that can predict syngas yield, tar concentration, and performance parameters was developed. Effects of some critical parameters such as gasification temperature, steam-fuel-ratio on hydrogen yield, tar content, and char conversion of three different crude oils were explored. Results showed that the hydrogen yield increases by increasing steam/fuel ratio from 0.5 to 0.7 (wt/wt), and then reduces smoothly due to the endothermic behavior of methane reforming reaction, which releases three hydrogen moles. It also found that as the temperature increases within the range, hydrogen yield increases dramatically, which can be explained according to the Le Chatelier's principle on the endothermic reforming reactions of methane and tar cracking. Modeling results validated against the experimental measurements and found to be in a good agreement.     

Syngas production from gasification of high sulfur fuel oil using a CO2 sorbent

Hydrothermal gasification is a thermochemical; process that operates at a temperature range of 800-1000 C, in order to convert solid and liquid feedstocks into chemicals or clean gaseous fuel known as syngas. In this research, an Aspen plus model of heavy oil was developed to investigate the effect of operating conditions and a CO₂ sorbent (CaO) on gas composition and gasification efficiencies. An increase in CaO/F ratio from 0.5 to 1.0 greatly reduced amount of produced CO₂ and increased H₂ due to positive performance of carbonation reaction in conversion of CO₂ to CaCO₃. Carbon Conversion Efficiency (CCE) initially increased by raising CaO/F, and then it is relatively decreased by a further increase in CaO/F.     

Energy and economic aspects of synthesis gas production from oil sludge and plastic waste

A series of experiments have been performed to investigate the influence of reaction temperature, the equivalence ratio (ER), and blending ratio on the gas composition, tar content and higher heating value (HHV) of synthesis gas. H₂ content decreased from 10.7 to 8.2% in the range of BR while CO and CH₄ increased from 17.4 to 23.1% and 3.4 to 6.3%, respectively. HHV increased with BR and H₂/CO showed an opposite trend. The highest HHV and H₂/CO were obtained at 100%PW and 100%OS, respectively. Tar content increased from 4.8 to 9.5?g/Nm³ with BR increasing in the range because of a reduction in the endothermic nature of volatile combustion.     

Steam gasification of oil sludge with calcined olivine

Abstract

Steam gasification of solid/liquid fuels is an efficient method for producing hydrogen and syngas. The purpose of this work was to examine the catalytic behavior of olivine in steam gasification of oil sludge. To achieve this, an Aspen Plus model was developed based on Gibbs free energy minimization. Results showed that the concentration of H₂, CO and CH₄ increased with adding the olivine particle, while CO₂ showed an opposite trend. With ER increasing from 0.12 to 0.36, H₂, CO and CH₄ decreased significantly, while CO₂ increased from 10.97 to 21.87. ER is an important parameter in the gasification process.     

鄂尔多斯盆地延长组7段页岩全组分定量生烃模拟及原油可动性评价

页岩油和致密油是中国目前油气勘探的热点,页岩生烃模拟实验可为此类油气资源勘探提供重要数据。以鄂尔多斯盆地延长组7段（长7段）页岩为例,利用金管-高压釜模拟生烃装置,系统研究了Ⅱ型有机质在与"生油窗"对应的成熟度范围（Easy R_o 0.7%~1.6%）内生烃产物中的气体烃（C_1-5）、轻烃（C_6-14）、重烃（C₁₄₊）、各族组分,以及生烃残渣的地球化学特征。发现长7段页岩在生油期可同时生成2.35~103.91 mL/g的气体烃和10.83~88.24 mg/g的轻烃。重烃的生成高峰对应的Easy R_o约为1.0%,与其中的饱和烃、芳烃和非烃的高峰产率对应的成熟度非常接近。重烃中沥青质的产率在Easy R_o约1.35%后开始下降,说明沥青质在此后才开始大量裂解与固化。而对原油物性影响很大的轻重比[（气体烃+轻烃）/重烃]及气油比[气体烃/（轻烃+重烃）]随成熟度增加而不断增大,其增速分别在Easy R_o为1.05%~1.15%之后明显变快。在生油过程中,长7段页岩残渣HI值和H元素的大量减少、干酪根固体碳同位素的变重均发生在Easy R_o约1.00%之前。干酪根碳同位素的变化相对较小,在鄂尔多斯盆地可以作为母源指标。通过对生烃产物中6种常见生物标志物成熟度参数的对比,证实多环芳烃成熟度参数中的甲基菲指数（MPI）和甲基菲比值（F1）在整个生油窗内都与成熟度有很好的线性相关性,可用于鄂尔多斯盆地母源为长7段页岩的原油成熟度判识。生烃产物的各地球化学特征变化节点、以及成熟度指标可用于鄂尔多斯盆地长7段页岩油或相关致密油资源的可采性评价。     

蓬莱与达里亚减压馏分的催化裂化反应规律

利用小型固定流化床实验装置考察了蓬莱与达里亚减压馏分（VGO）的催化裂化反应性能,研究了反应温度、剂油比、空速和水油比对产物分布的影响。结果表明：轻油收率随反应温度与剂油比的减小以及空速与水油比的增大而增大;在反应温度500 ℃、剂油质量比6、质量空速20 h-1和水油质量比0.08的工业操作条件下,蓬莱VGO的转化率为92.18%,轻油收率为62.62%,总液体收率为81.71%,达里亚VGO的转化率为94.14%,轻油收率为64.14%,总液体收率为82.63%;在反应温度490 ℃、剂油质量比5、质量空速25 h-1和水油质量比0.10的较优操作条件下,蓬莱VGO的转化率为91.98%,轻油收率为66.54%,总液体收率为84.09%,达里亚VGO的转化率为93.59%,轻油收率为70.98%,总液体收率为84.86%。总体来说,达里亚VGO的裂化性能优于蓬莱VGO。     

Thermal cracking of tar generated from steam gasification of petroleum residue using dolomite particles

Gasification is a thermochemical process that converts carbon-based fuels into a clean synthesis gas (so-called syngas). The produced syngas can be used directly as a fuel to produce electricity in gas engines or an intermediate chemical for production of Dimethyl ether (DME), methanol (MeOH), and/or ethanol. In this work, an unsteady-state, kinetic model that is used to predict the gas composition and performance indicators in presence of dolomite was developed. Results showed a good performance for biomass gasification in presence of dolomite as a catalyst. It is also concluded that the tar destruction ratio (TDR) exhibits an increasing trend with increasing [CaMg (CO₃)₂]/[C] from 0.1 to 0.9 (mg/mg), while after that, the increase levels off.     

醋糟间歇气化制备燃气试验

醋糟是酿造食醋后所剩余的残渣,由于醋糟具有盐度高、酸性强、自然分解慢等特点,将醋糟气化后制备燃气,对于提高酿醋行业资源利用率、减小环境污染均具有重要的意义。为此,采用单一流化床两步气化方法,以煤作为热载体与发热体,纯水蒸气作为气化介质,在自行研制的实验装置上进行了醋糟气化制备燃气的试验,探讨了气化温度(900~1 000℃)、水蒸气与醋糟质量比(1.23~3.57)对燃气组分(H2/CO、CO/CO2等)、产率、低热值等的影响。在实验研究的条件范围内,燃气中(H2+CO)含量为67.07%~73.72%,燃气产率为0.32~0.72m3/kg,低位热值为10 757.2~11 746.16kJ/m3。试验结果表明:①H2和CO是燃气中最主要的2种气体,随着气化温度的升高,燃气中H2与CO含量、CO/CO2值和燃气产率均增加,而CH4与CO2含量、H2/CO值和燃气低位热值则相应地减少;②随着水蒸气与醋糟质量比的增加,燃气中H2与CH4含量、H2/CO值、燃气产率和低位热值均增加,而CO含量呈现下降趋势。结论认为:该单一流化床两步气化系统能够稳定获得富含氢气的燃气,并可长时间平稳、安全、可靠地运行。     

不同沥青质含量渣油临氢热转化反应特性研究

以塔河常压渣油为原料、正己烷为溶剂沉淀出沥青质,并将其回调至渣油中配制成不同沥青质含量的油样进行高压加氢热转化实验;利用热重并结合1H-NMR和13C-NMR对反应产物中不饱和亚组分进行表征。结果表明：随着配制油样中沥青质含量的增加,焦炭和气体收率均呈线性增加趋势,次生饱和分收率在沥青质质量分数为30%时,取得极大值55.04%;不饱和亚组分均发生了烷基侧链的断裂脱落及环烷环开环裂解,致使芳香氢和芳环α位氢含量增加,且饱和碳分率呈显著降低趋势,而芳碳分率、共二环芳碳分率和共三环芳碳均表现为大幅度增加的变化趋势。     

塔河常压渣油中亚组分化学组成与结构分析

以塔河常压渣油为原料、正己烷为溶剂沉淀出沥青质,并将其回调至渣油中配制成不同沥青质含量的油样进行高压加氢热转化实验;利用热重并结合1H-NMR和13C-NMR对反应产物中不饱和亚组分进行表征。结果表明：随着配制油样中沥青质含量的增加,焦炭和气体收率均呈线性增加趋势,次生饱和分收率在沥青质质量分数为30%时,取得极大值55.04%;不饱和亚组分均发生了烷基侧链的断裂脱落及环烷环开环裂解,致使芳香氢和芳环α位氢含量增加,且饱和碳分率呈显著降低趋势,而芳碳分率、共二环芳碳分率和共三环芳碳均表现为大幅度增加的变化趋势。     

全馏分高温煤焦油悬浮床加氢裂化中试试验

采用150 kg/d悬浮床加氢裂化中试装置,以全馏分高温煤焦油为原料,考察了反应温度、反应质量空速及反应压力对煤焦油加氢裂化反应性能及产物分布的影响。结果表明：升高反应温度和降低反应质量空速,均可以促进煤焦油中重油和沥青质的深度转化,气体和焦炭收率增加,重油收率降低,但过高的反应温度会降低轻油馏分收率;提高反应压力可以抑制气体和焦炭的生成,促进沥青质的加氢转化,保证了较高的轻油收率。在反应温度为465℃,反应压力为22 MPa,反应质量空速为0.5 h-1,氢气/原料油（体积质量比,L/kg）为1 500的最佳条件下,重油和沥青质的转化率分别达到26.05%和62.95%,轻油收率为77.42%,气体和焦炭收率为17.28%。     

Asphaltene Precipitation During Different Production Operations

Asphaltene precipitation due to enhanced oil recovery (EOR) methods or natural depletion is a serious technical problem at petroleum industry. The authors present the result of asphaltene precipitation during associated gas injection, CO₂ injection, and natural depletion in reservoir condition. In addition, the effect of variations in operation pressure, injection gas concentration, and production rate on asphaltene precipitation and difference between slope of precipitation graph due to various method of EOR or natural depletion were investigated. The results revealed that temperature has an efficient role on result of asphaltene deposition through associated gas and CO₂ injection. By decreasing temperature, the amount of asphaltene precipitation due to associated gas injection was increased. In fact, recovery of gas injection was decreased at lower temperatures, hence; solubility has an important rule on asphaltene precipitation.