地下煤炭气化发电机组运行特性Yong分析

地下煤气化的产物除用作矿区居民家用燃料，还用内燃机组进行了地下煤气化发电的工业性试验。运用Yong分析方法对地下煤气化发电机组的运行参数和运行特性进行了研究，得出了造成Yong损的主要环节，进一步提出了采用先进燃气轮机的地下整体煤气化联合循环(UIGCC)发电技术有效提高地下气化煤气能量利用率，为地下煤气化发电技术的推广应用提供了技术依据。     

地下煤炭气化发电机组运行特性(火用)分析

地下煤气化的产物除用作矿区居民家用燃料,还用内燃机组进行了地下煤气化发电的工业性试验.运用(火用)分析方法对地下煤气化发电机组的运行参数和运行特性进行了研究,得出了造成(火用)损的主要环节,进一步提出了采用先进燃气轮机的地下整体煤气化联合循环(UIGCC)发电技术有效提高地下气化煤气能量利用率,为地下煤气化发电技术的推广应用提供了技术依据.     

让煤矿"喷"煤气

全世界煤的储藏量远远高于石油和天然气。全世界尚未开采的煤层有几万亿 t。到目前为止 ,要利用这些储藏的煤中的大部分的前景似乎还很遥远 ,因为开采成本太高 ,而且又出现了更加便宜、更加干净的能源。但是 ,地下煤气化技术有可能会改变所有这一切。澳大利亚政府研究机构 Cs I     

广义不可逆卡诺热机的有限时间经济性能分析

研究了牛顿定律系统广义不可逆卡诺热机有限时间(火用)经济性能,导出了存在热阻、热漏和其他内不可逆性时的最优利润率的解析式和最大利润率及相应的效率界限.     

2001年美国气化技术会议梗概

由美国气化技术协会 ( GTC)和电力研究院( EPRI)组织的第 2 1届气化技术年会于 2 0 0 1年 1 0月初在圣·弗朗西斯科市召开。参会代表来自 30个独立电站、1 6个电建工程公司、2 0多个石化公司以及 1 4个设备供货商。会上特别感兴趣的技术和议题是 :·地下煤气化 ;·离子交换膜 ;·若干工业问题及需要。地下煤气化林克能源 ( Linc Energy)公司正在建一座地下煤气化电厂 ,它位于澳大利亚昆士兰州的布里斯班西 35 0 km的青切拉 (译音 )镇。该技术不算新 ,在前苏联用到商业化项目上已有 40多年的历史 ,但是这个项目却代表着该技术在另一个地…     

硫对煤与五氯酚混烧过程二英生成影响规律的试验研究

二(口恶)英是环境中的痕量剧毒有机污染物,对人类健康极具危害.本文以垃圾中的典型成份五氯酚(PCP)为研究对象,研究了煤和PCP混烧过程中,元素硫及煤中硫对烟气中二(口恶)英生成的影响.煤的加入(特别是高硫煤的加入)可以明显降低二(口恶)英生成.试验结果表明煤和PCP混烧时,只要燃料中的S/Cl的摩尔比大于0.4时就能实现对燃烧过程中前驱物生成二(口恶)英反应超过80%的抑制效率,当S/Cl比在0.7～1范围内的抑制效果较好.本文的实验结果对于探明实际垃圾焚烧过程中二(口恶)英的生成机理和影响因素具有重要指导意义.     

南非计划建造以地下煤气化运行的2100MW IGCC电厂

据《Gas Turbine World》2007年7-8月刊报道，Eskom公司已宣布一项设计研究计划，在Mpumalanga的Majuba煤田建造一座2100MW的IGCC电厂，该电厂在设计时将结合采用地下煤气化技术。     

煤气化特性研究的现状与展望

对煤气化特性的基础研究和气化技术工艺的最新研究进展进行了综述,重点介绍了煤气化技术工艺路线和煤气化特性的研究方法与研究进展,并提出了在直流电弧炉中进行煤气化的研究新方向。     

整体煤气化联合循环系统的可靠性分析与设计

成本过高和可靠性较低是制约整体煤气化联合循环整体煤气化联合循环商业化的重要因素.从系统方面对不同配置的整体煤气化联合循环进行了可靠性建模与分析,并对单列整体煤气化联合循环系统进行了可靠性设计.结果表明:当前单列整体煤气化联合循环系统的可用度只有70%左右,采用多列耦合或备用气化炉能够大幅度提高整体煤气化联合循环系统可用度;要使单列整体煤气化联合循环可用度不低于90%,要求气化炉可用度高于94%,燃气轮机可用度高于97%,余热锅炉的可用度也需要较大幅度的提高.     

煤气化燃烧在中小型锅炉的应用

简述煤气化燃烧的技术原理,介绍中小型锅炉煤气化燃烧的主要工艺流程,分析工艺流程的利弊,指出中小型锅炉煤气化燃烧设计中应注意的几个要点.     

An energy-exergy analysis of the Koppers-Totzek process for producing hydrogen from coal

Energy and exergy analyses of the Koppers-Totzek (KT) coal gasification process were performed. The KT process involves the partial oxidation of coal with oxygen and steam to produce a synthesis gas, and the treatment of the synthesis gas to yield hydrogen. The analyses were carried out using a process-simulation computer code which had been enhanced by the authors for exergy analysis. The exergy efficiency for the overall process was found to be 49%, and the energy efficiency 59%. The majority of energy losses was found to be associated with emissions of cooling water and stack gas. The majority of exergy losses was found to be due to internal consumptions, particularly within the gasification and steam generation systems. The losses associated with the cooling water and stack gas streams, although significant on an energy basis, are shown to be not that important on an exergy basis.     

粉煤加压气化小型试验研究

煤气化技术是燃煤联合循环发电、煤化工、综合利用系统、近零排放系统中的核心技术。干煤粉加压氧气气化技术是煤气化技术发展的一个主流方向。介绍了国电热工研究院的干煤粉加压气化试验系统,以及干煤粉加压气化试验研究的过程和结果。试验结果达到了预期的目的,得到干煤粉加压气化过程的规律,并验证了试验系统在高压下的稳定性。     

A novel hydrogen production system based on the three-step coal gasification technology thermally coupled with the chemical looping combustion process

Coal gasification technology is a significant process for the coal-based hydrogen production system and is considered as a key technology in the transition to “Hydrogen Economy”. To decrease the exergy destruction and enhance the cold gas efficiency of the coal gasification process, a novel three-step gasification technology thermally coupled with the chemical looping combustion process is proposed. And the hydrogen production system with CO₂ recovery is integrated based on the three-step gasification technology. Results indicated that the cold gas efficiency of the three-step coal gasification technology is 86.9%, which is 10.1% points enhanced compared with GE gasification technology. Besides, the novel system has an energy efficiency of 62.3%, which is 3.1% higher than that of the reference system. Exergy analysis presented that the employment of the three-step gasification technology contributed to the reduction of system exergy destruction by 4.2%. Furthermore, the energy utilization diagram (EUD) suggested that matching between endothermic reactions and exothermic reactions plays important role in the enhancement of cold gas efficiency.     

现代煤气化制合成气的工艺

叙述了国内外先进的Texaco气化工艺,Shell气化工艺,GSP气化工艺等3种气流床气化工艺及从气化压力,气化温度及产出合成气组分等方面进行比较的结果,指出,若是煤种适合制浆选择Texaco气化技术性价比较高;Shell气化炉适合用于发电,用于煤化工存在风险;GSP在煤化工领域有很大的发展前景。     

Exergy analysis in the assessment of hydrogen production from UCG

The demand for H₂ increases rapidly with the gradual recognition of the potential of H₂ as an important secondary energy. At present, coal gasification is the main way to obtain hydrogen on a large scale and at a low cost in China. The underground coal gasification (UCG), as a kind of in-situ utilization technology that can exploit the unreachable deep coal resources, could become an alternative H₂ production pathway. This paper presents comparative study of energy utilization and resource consumption in H₂ production by UCG and typical surface coal gasification (SCG) technology, namely Lurgi fixed bed gasification, with 1.2 billion Nm³/a throughput of H₂ as example, to offer corresponding data support. The efficiency and the amount of resources consumed in constructing and operating each coal-to-hydrogen system under different conditions have been researched from exergetic point of view, which is not reported in existing literatures. In this paper, the exergy efficiency is calculated to be 40.48% and 40.98% for hydrogen production using UCG and SCG. The result indicates the competitiveness of UCG in the field of hydrogen production comparing with widely used coal gasification technology. The resource consumption is measured by cumulative exergy consumption (CExC), which is 8.17E+10 MJ and 6.57E+10 MJ for H₂ production from UCG and SCG. The result shows that although the H₂ production from UCG has higher CExC, it can significantly reduce the resource consumption of equipment comparing with H₂ production from SCG, indicating its advantage in total investment. It is found that the exergy efficiency increases with the rise in H₂O-to-O₂ and O₂-to-CO₂ ratio, while the value of CExC decreases with the appreciation of H₂O-to-O₂ ratio yet increases as the O₂-to-CO₂ ratio rises. In addition, the sensitivity analysis of production capacity reveals that the exergy efficiency gap and CExC gap between hydrogen production by UCG and SCG diminishes at smaller scale production capacities, showing that UCG is more suitable for small-scale hydrogen production.     

Integration of underground coal gasification with a solid oxide fuel cell system for clean coal utilization

Underground coal gasification (UCG) is a promising clean coal technology. Typically, the syngas obtained from UCG is used for power generation via the steam turbine route. In the present paper, we consider UCG as a hydrogen generator and investigate the possibility of coupling it with a solid oxide fuel cell (SOFC) to generate electrical power directly. We show, through analysis, that integration with SOFC gives two specific advantages. Firstly, because of the high operating temperature of the SOFC, its anode exhaust can be used to produce steam required for the operation of UCG as well as for the reforming of the syngas for the SOFC. Secondly, the SOFC serves as a selective absorber of oxygen from air which paves the way for an efficient system of a carbon-neutral electrical power generation from underground coal. Thermodynamic analysis of the integrated system shows considerable improvement in the net thermal efficiency over that of a conventional combined cycle plant.     

Thermodynamic and economic analyses of a coal and biomass indirect coupling power generation system

The coal and biomass coupling power generation technology is considered as a promising technology for energy conservation and emission reduction. In this paper, a novel coal and biomass indirect coupling system is proposed based on the technology of biomass gasification and co-combustion of coal and gasification gas. For the sake of comparison, a coal and biomass direct coupling system is also introduced based on the technology of co-combustion of coal and biomass. The process of the direct and the indirect coupling system is simulated. The thermodynamic and economic performances of two systems are analyzed and compared. The simulation indicates that the thermodynamic performance of the indirect coupling system is slightly worse, but the economic performance is better than that of the direct coupling system. When the blending ratio of biomass is 20%, the energy and exergy efficiencies of the indirect coupling system are 42.70% and 41.14%, the internal rate of return (IRR) and discounted payback period (DPP) of the system are 25.68% and 8.56 years. The price fluctuation of fuels and products has a great influence on the economic performance of the indirect coupling system. The environmental impact analysis indicates that the indirect coupling system can inhibit the propagation of NO_x and reduce the environmental cost.     

660 MW燃煤发电机组的碳捕集系统余热利用和集成系统性能评估

碳捕集与封存（CCS）技术能有效捕获燃煤电厂排放的CO₂但再生能耗大且效率低。为提高燃煤电厂能源利用效率,提出集成有机朗肯循环（ORC）与CCS的太阳能-燃煤发电系统,利用热力学、火用和经济性分析模型对集成系统进行参数敏感性分析。基于外部燃料火用矩阵模型,分析再沸器所需热量中CO₂压缩过程和太阳能集热器的热量占比及集成ORC系统对外部燃料火用贡献度的影响。研究表明：当热源比θ=0.4时的集成系统热经济性能最优且具有较合理的不可逆性;集成ORC系统后锅炉燃煤火用、一、二次再热燃煤火用对系统产品的贡献度均有所提高;随着θ增加,锅炉燃煤火用和一、二次再热燃煤火用对碳捕集系统产品的贡献度逐渐降低;压缩余热火用和太阳能火用的贡献度逐渐增加。     

Underground coal gasification: From fundamentals to applications

Underground coal gasification (UCG) is a promising option for the future use of un-worked coal. UCG permits coal to be gasified in situ within the coal seam, via a matrix of wells. The coal is ignited and air is injected underground to sustain a fire, which is essentially used to “mine” the coal and produce a combustible synthetic gas which can be used for industrial heating, power generation or the manufacture of hydrogen, synthetic natural gas or diesel fuel. As compared with conventional mining and surface gasification, UCG promises lower capital/operating costs and also has other advantages, such as no human labor underground. In addition, UCG has the potential to be linked with carbon capture and sequestration. The increasing demand for energy, depletion of oil, and gas resources, and threat of global climate change have lead to growing interest in UCG throughout the world. The potential for UCG to access low grade, inaccessible coal resources and convert them commercially and competitively into syngas is enormous, with potential applications in power, fuel, and chemical production. This article reviews the literature on UCG and research contributions are reported UCG with main emphasis given to the chemical and physical characteristic of feedstock, process chemistry, gasifier designs, and operating conditions. This is done to provide a general background and allow the reader to understand the influence of operating variables on UCG. Thermodynamic studies of UCG with emphasis on gasifier operation optimization based on thermodynamics, biomass gasification reaction engineering and particularly recently developed kinetic models, advantages and the technical challenges for UCG, and finally, the future prospects for UCG technology are also reviewed.     

Comparisons of MHD topping combined power generation systems

The efficiencies of six MHD topping combined power generation systems and one gas turbine topping combined system driven by different combinations of fuel and oxidant supply schematics were compared and classified on the bases of overall chemical reaction models for the combustion and gasification processes. The primary fuel was carbon that modeled a coal. The fuel types considered were coal and coal-synthesized gases which were provided by either conventional top gasification or by the tail gasification process. The oxidant was either pure oxygen, oxygen enriched air or air. In the MHD topping cases, the oxidant was preheated to each appropriate temperature. The enthalpy extraction of the corresponding power generation units in the topping and bottoming systems and the temperatures at the inlets of regenerators as well as at the stacks were assumed to be identical in all cases, except the inlet temperatures at the recuperative air heaters and the steam generators. We showed that the tail gasification system with an MHD topping and a combined gas turbine and steam turbine bottoming exhibited the highest plant efficiency insofar as it was based on the state-of-the-art technology of the power generation units and the heat exchanger.