Computer-based model of crude oil gasification in a fluidized bed

Gasification is a high-temperature, low-cost, and environmentally friendly process with uses as an alternative method to convert the carbon-based fuels into a clean syngas for engineering applications. In this work, the authors developed a mathematical model of crude oil for evaluating the crude oil potential to produce a clean and high caloric value syngas. The influence of some critical parameters during crude oil gasification including equivalence ratio, excess oxygen ratio (EOR), and residence time on tar yield, syngas caloric value, and char conversion was investigated. Results showed that with increasing the EOR, the char was converted continuously due to a significant improvement in the nature of endothermic reactions involved. It is also found that when the EOR increases from 0.2 to 0.8, gas caloric value improves, slightly.     

A parametric study for gasification of liquid fuels

Gasification is a clean technology for production of high caloric value syngas. In this study, a kinetic model of gasification of heavy oil is developed to investigate the influence of oxygen ratio and pressure on the quality of syngas and performance parameters. Results showed that the oxygen ratio improves the caloric value of syngas and gasification efficiency, and also found that the pressure has a minor effect on the process. The model was validated against experimental data and found to be in good agreement.     

An artificial neural network framework for gasification of liquid fuels under oxy-fuel conditions

Gasification is a clean thermochemical process which converts carbon-based fuels into syngas. In this work, an artificial neural network model of heavy oil gasification under different gasifying agents was developed. Model was validated with the experimental data from literature. Effect of important parameters such as equivalence ratio and oxygen ratio (OR) on the higher heating value (HHV) of the produced syngas, gasification efficiency (GE), carbon conversion efficiency (CCE) was studied. With OR increasing from 0.366 to 0.41, GE and syngas HHV decreased, but CCE increased.     

A computational fluid dynamic model for evaluating the performance of crude oil gasification

Gasification is a clean technology which converts the liquid or solid fuels into a high caloric value syngas for power generation. In this research work, we developed a computational fluid dynamic model of crude oil gasification for hydrogen production; the accuracy of the model was approved in our previous work. Effects of some important factors such as residence time, steam/fuel ratio and equivalence ratio on hydrogen yield, and char conversion were explored. Results showed that the residence time and steam/fuel ratio play a major role in the process. It was also found that the equivalence ratio has a negative effect on the hydrogen yield and a positive effect on the char conversion.     

CFD simulation of entrained-flow gasification of liquid fuels

In this study, a CFD model of entrained-flow gasification of petroleum residue proposed to simulate the effects of some critical parameters such as equivalence ratio and system pressure on carbon conversion efficiency, tar yield, hydrogen concentration, and higher heating value of the syngas. It is a 2D model and steady state, which can be used as a general model to evaluate the performance parameters of other fuels (coal, biomass, and municipal solid wastes) during gasification process. Results showed the equivalence ratio has a negative effect on the higher heating value of the syngas and a positive impact on the gasification efficiency. It also found that the carbon conversion efficiency strongly depends on the equivalence ratio and gasification temperature. The model validated against experimental observations and found to be in good agreement.     

A kinetic model for gasification of heavy oil with in situ CO2 capture

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. A gasification kinetic model of heavy oil in the presence of CaO that can predict syngas yield, tar concentration, and performance parameters has been developed. Results showed that the CaO plays a major role for a significant reduction in carbon dioxide during the process. Based on the operating conditions, it was also found that there is an optimum condition for tar yield. Modeling results were validated against experimental data and found to be in good agreement.     

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.     

Aspen plus simulation of heavy oil gasification in a fluidized bed gasifier

Gasification is a clean technology to convert fuels to high-quality syngas in presence of a gasifying agent. In this study, an Aspen Plus model of heavy oil gasification was developed to produce the hydrogen rich syngas. Effect of some parameters such as gasification temperature and steam/fuel ratio on the hydrogen yield and was investigated. Results showed that the temperature plays a major role in the process; higher temperatures produce the higher hydrogen content. It was also found that the operation under high steam/fuel ratio can cause a significant increase in the hydrogen yield. The modeling results were compared with the experimental data available in the literature and found to be in good agreement.     

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.     

Effects of residence time and heating rate on gasification of petroleum residue

Gasification of petroleum residue has been considered as the potential technology due to the advantages of converting the liquid fuels into syngas using partial oxidation. In this paper, we developed a one-dimensional kinetic model to simulate the effects of residence time and heating rate on the gasification characteristics. Results showed that gasification under higher heating rate improves the hydrogen yield and carbon conversion efficiency. It was also found that the residence time plays a major role in the process; higher residence time improves the hydrogen yield and gasification efficiency. The model was validated against the reported data and found to be in good agreement.     

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.     

有机固体废弃物化学链气化技术研究进展

化学链气化技术(CLG,Chemical looping gasification)是基于化学链燃烧技术(CLC,Chemical looping combustion)发展而来的一种新颖的固体燃料气化技术.相较于常规气化技术,化学链气化技术省去了氧气制备、且不需要燃料燃烧来提供热量,具有合成气不被氮气稀释、焦油及N/...     

A Comprehensive Study on Gasification of Petroleum Wastes Based on a Mathematical Model

Gasification is a thermochemical process that produces useful and environmentally friendly by-products. Here the effects of various parameters such as equivalence ratio, pressure, and steam gasifying on the gasification process of waste lubricant oil are investigated based on Gibbs free energy minimization approach. The model is validated by reported data and found to be in good agreement. Various gasification performance parameters such as cold gas efficiency, carbon conversion efficiency, gasification temperature, pressure, and heating value of produced gas were determined based on a parametric study. The use of CaO catalyst has also been investigated for the production of hydrogen-rich gas with in situ CO₂ capture in steam gasification of waste oil. The results indicate that an appropriate steam/fuel ratio and more catalyst are favorable for getting a higher H₂ ratio and a lower CO₂ output.     

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.     

The prediction of the concentrations of syngas components produced during non-catalytic steam gasification of bitumen

In this article the results of calculation for concentrations of syngas components produced during non-catalytic steam gasification of bitumen in consideration of chemical kinetics are presented. As an object of research the natural bitumen of Ashalchinskoe oil field of Tatarstan Republic (Russia) was chosen. The rate constants values of chemical reactions for bitumen gasification process were obtained using thermogravimetric analysis (TGA). Results were compared with the data of other researchers and showed a good convergence.     

流化床中造纸黑液催化石油焦气化特性

利用实验室规模流化床气化反应器,考察了造纸黑液对石油焦水蒸气气化反应的催化效果,并分析了其催化反应机理。结果表明,造纸黑液不仅能显著提高石油焦的气化反应活性,还能大幅提高气化气中H₂的含量。脱水黑液添加量为黑液与石油焦质量之和的10%时催化效果较好,达到相同气化反应速率时的反应温度比纯石油焦气化低200℃左右;在相同反应温度下提高气化反应速率5倍左右,可提高气化气中H₂体积分数约8百分点。黑液中的碱金属活性组分能够破坏石油焦中的C=C芳香结构,同时与石油焦中的碳结合生成活性较高的碳氧复合物C(O),从而提高气化反应速率;碱金属还促进了水煤气变换和CH₄水蒸气重整反应,使得H₂的生成量增多。因此,造纸黑液是一种有效的石油焦气化生产富氢合成气的催化剂。     

Steam gasification of bitumen oil in presence of Ni/dolomite catalysts

An important step in developing clean energy and reducing greenhouse gas emissions is the use of clean technologies such as gasification. In this work, we were used a bubbling fluidized bed (BFB) to convert the bitumen oil into a clean syngas in presence of three kinds of Ni/dolomite catalysts. While all three catalysts were acceptable in the process of tar elimination, but DN-22 was more successful in eliminating tar than the other two samples, which might be due to the higher amount of CaO in the composition DN-22. With increase in Ni, the amount of eliminated tars in the tar cracking process was also increased due to the delay in the deactivation of the dolomite catalyst.     

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。     

Modeling crude oil gasification

Abstract

The characteristics of CO₂-gasification of crude oil under steady-state condition were studied using a simulator. The model was developed using the minimization Gibbs free energy minimization. The effects of reactor temperature and CO₂/crude oil ratio on gas composition and lower heating value (LHV) of the produced syngas were investigated. As a result, the maximum LHV was obtained at a CO₂/crude oil ratio of 0.1 and gasification temperature of 800?°C.     

从战略高度认识和推进天然气替代交通运输燃料

交通运输能源的低碳多元化是当前中国抑制石油对外依存度过快攀升的紧迫需要。为此,通过分析不同交通运输替代燃料的发展趋势,指出在天然气（LNG/CNG）、电、生物质和煤基燃料3大类交通运输燃料替代物中,LNG和CNG技术最成熟、成本最低、竞争力最强（天然气作为发动机燃料具有单位热值最高、尾气排放最少、CO₂排放量仅为同热值汽柴油排放量的3/4的优点,有利于改善大气质量）,且LNG和CNG的供应具有保障性（至少到2030年,中国将有进口LNG、非常规天然气和小气田就地液化的LNG、管网天然气液化的LNG、城市燃气门站或调压站液化的LNG等4种LNG供应源,足以保障到2030年有1 000×10⁸ m³/a 的LNG和CNG供应量）,价格较低且比较稳定。因此,推进天然气汽车（LNGV和CNGV）在中国的发展,加速其替代目前占中国交通运输能源93%、占原油总耗量60%的汽柴油车的进程,对保障国家战略安全具有极其重要的意义。结论认为,政府及早制定相关规划、标准、法律法规是推进天然气替代交通运输燃料发展的关键。