浅谈生物质气化在发电技术应用

随着经济的发展,世界各国电力需求猛增,电力供应日益紧张,在这种环境下,通过气化发电技术,把生物质能转化为电能,既能大规模处理生物质废料,又能提供电力,具有明显的社会和经济效益。介绍了生物质气化发电技术的国内外发展现状,着重讲述了生物质气化发电技术的原理、特点和分类,以及各类生物质气化发电技术的特点,分析了生物质气化发电技术的社会效益及应用前景。指出在我国这样一个农业大国应该大力发展生物质气化发电技术。     

农业生物质气化发电技术应用分析

本文从农业生物质气化过程的特点出发，分析了各种气化发电系统的技术水平及技术关键，同时从经济及社会的角度，分析了各种农业生物质气化发电设备的效益，指出只要继续提高技术水平并降低成本，农业生物质气化发电技术将很快进入工业应用，并在开源节流方面发挥重要的作用。     

生物质气化发电在分布式能源中的应用

阐述了分布式能源和生物质气化发电及它们之间的联系;介绍了生物质气化发电的几种利用形式;展望了生物质气化发电在分布式能源中的应用前景。     

生物质气化耦合燃煤发电技术的应用

生物质气化耦合燃煤发电技术是生物质资源利用的重要发展方向。根据生物质气化耦合燃煤发电技术的原理,进行生物质气化耦合燃煤发电的实际应用,研究该技术在应用过程中存在的一些问题及对策,说明生物质气化耦合燃煤发电是生物质高效和经济的应用途径之一。     

生物质流化床气化技术应用研究现状

按所得产品不同,可将生物质气化技术分为制氢、发电和合成液体燃料3大类。文章介绍了生物质流化床水蒸气气化制氢、催化气化制氢和超临界水气化制氢的工艺特点;分析了生物质流化床气化发电的技术、经济可行性;简述了生物质流化床气化合成液体燃料的研究现状;指出气化产出气化学当量比调变、焦油去除问题和合成气净化是生物质流化床气化技术应用的主要瓶颈,认为定向气化是今后研究的主要方向。     

生物质气化内燃机发电可行性分析

不同于传统化石能源,生物质能源是一种可再生能源,生物质气化发电技术的应用能够减少对化石燃料的依赖,保护环境并推动可持续发展。主要从生物质气化内燃机发电的原料分布、原料采集加工、气化工艺、发电规模、运行成本等方面对其可行性进行了综合分析。通过分析得出,生物质气化发电的主要成本为原料收集及加工成本,因此生物质气化发电技术适宜在农业发达地区或林木资源丰富的地区推广,除了发电收益外,配合气化炉副产物稻壳炭等能够大幅缩短回收周期。     

生物质气化斯特林发电单元系统设计

通过梳理现有生物质气化发电系统发电中出现的问题,提出了采用生物质气化斯特林发电单元系统.介绍了该系统的组成,分析了其球笼式框架结构、余热利用装置结构及散热系统结构,并进行了实验分析.实验结果表明,该生物质气化斯特林发电单元系统能有效提升发电功率,适合大规模建设分布式斯特林发电站发展的要求.     

生物质直燃和混燃发电环境效益分析

利用生物质代替矿物燃料发电可以减少CO2和SO2的排放量。确定了燃煤机组CO2和SO2排放量基准,建立生物质发电的CO2和SO2的排放量模型及其偏差模型;计算不同发电方式下CO2和SO2的生成量及减排量;分析了气化炉气化效率对生物质发电CO2和SO2生成量的影响。结果表明,提高生物质发电效率和气化效率可以显著降低CO2和SO2的排放;生物质发电的环境效益明显优于燃煤发电,而生物质气化合成气与煤混燃发电的环境效益优于生物质直燃发电。     

生物质气化—燃料电池发电系统性能分析

建立了基于热力学平衡的生物质气化模型,利用平衡模型分析了气化过程的特性,研究了气化过程的反应规律及各种因素对气化性能指标的影响,详细分析了当量比及物料湿度对气体产物成分及气化产物热值的影响.同时,建立了以生物质气为燃料的固体氧化物燃料电池的数学模型,该模型考虑了燃料电池的能斯特电动势及各种极化损失.利用建立的模型分析了操作参数以及物料湿度和生物质种类对生物质气化—燃料电池发电系统性能的影响.结果表明,生物质气化—燃料电池发电系统的发电效率可达30％,热电联产效率最高可达95％以上.     

生物质气化发电技术的进展

本文对各种生物质气化发电技术及该技术在国内外的发展现状做了综述.目前我国的生物质气化发电仅仅是初具规模,热效率很低且存在不少技术问题.要利用气化发电技术创造良好经济效益,同时取得良好的环保效益,在解决技术性问题的同时,一定要因地制宜采用适宜的气化发电技术形式.     

双工质并联型联合循环热电冷三联产总能系统的研究

该文将并联型联合循环和三联产技术相结合，提出了综合利用能源的新思路，并对HAT循环和STIG循环构成的热电冷三联产总能系统进行了研究和比较，得出了有关并联型联合循环热电冷三联产总能系统的一些有用的结论。图5参5     

Performance improvement for a simple cycle gas turbine GENSET––a retrofitting example

Due to the serious power shortage in Taiwan, many simple cycle gas turbine generation sets (GENSETs) that were originally designated to serve as peak load units are forced to operate continuously during the entire summer season. The retrofitting projects have been seriously considered to convert these GENSETs (which have the advantage of fast startup, but suffer from low power output and thermal efficiency at high ambient temperature) into more advanced cycle units with higher efficiency and higher output. Among many proven technologies, such as inlet air cooling, intercooling, regeneration, reheating and steam-injection gas turbine (STIG) etc., STIG is found to be one of the most effective in boosting both the output capacity and thermal efficiency. The results from computer simulation indicated that the retrofitting of existing GE Frame 6B simple cycle unit into STIG cycle can boost the output from about 38 to 50 MW, while the generation efficiency can be increased from about 30% to 40%. Besides, the power output of STIG cycle is less sensitive to ambient temperature than that of simple cycle. NO_x reduction to less then 25 ppm (when LNG is used) and operating flexibility under variable heat demand could be achieved.     

PEvGT循环参数优化及热力性能分析

PEvGT循环是湿空气透平(HAT)循环和注蒸汽燃气轮机(STIG)循环的结合,既具有较高的发电效率,又可对外提供蒸汽并实现灵活的热电比调节,具有在热电联供领域应用的潜力。对配置不同的两种PEvGT循环进行了参数优化,分析了其热力性能和热电联供特性。研究表明:纯发电时,两种PEvGT循环的效率最高点对应的分流比在0～20%之间。未加湿空气、加湿空气及蒸汽在回热器前混合(PEvGT-2),循环最佳压比与HAT循环最佳压比为10左右;最高效率为51.4%比HAT循环及STIG循环分别高出0.8和3个百分点。未加湿空气和蒸汽在回热器后与湿空气混合(PEvGT-1),循环最佳压比较高且最高效率与STIG循环相当。热电联供时,两种PEvGT循环具有与STIG循环相似的热电负荷灵活性,且在蒸汽输出比例相同时,PEvGT-1与PEvGT-2循环的发电效率分别比STIG循环高0.7～1.5和3.4～12个百分点。     

燃气轮机STIG化的研究

燃气轮机回注蒸汽循环具有高效率、高比功及系统组成的简单性等特点受到广泛注意。能在现有的燃气轮机上实施STIG化是STIG发动机能迅速实用化的重要原因之一。本文讨论了对现有燃气轮机进行STIG化改装中的某些问题,并分析了在工业上采用单轴,双轴和叁轴燃气轮机STIG化的工作情况,从中得出了一些结论。     

Blade cooling optimisation in humid-air and steam-injected gas turbines

Humidified gas turbine cycles such as the humidified air turbine (HAT) and the steam-injected gas turbine (STIG) present exciting new prospects for industrial gas turbine technology, potentially offering greatly increased work outputs and cycle efficiencies at moderate costs. The availability of humidified air or steam in such cycles also presents new opportunities in blade and disk cooling architecture. Here, the blade cooling optimisation of a HAT cycle and a STIG cycle is considered, first by optimising the choice of coolant bleeds for a reference cycle, then by a full parametric optimisation of the cycle to consider a range of optimised designs. It was found that the coolant demand reductions which can be achieved in the HAT cycle using humidified or post-aftercooled coolant are compromised by the increase in the required compression work. Furthermore, full parametric optimisation showed that higher water flow-rates were required to prevent boiling within the system. This corresponded to higher work outputs, but lower cycle efficiencies. When optimising the choice of coolant bleeds in the STIG cycle, it was found that bleeding steam for cooling purposes reduced the steam available for power augmentation and thus compromised work output, but that this could largely be overcome by reducing the steam superheat to give useful cycle efficiency gains.     

Regenerative steam-injection gas-turbine systems

There is a demand for developments of the distributed energy system using a small-scale gas turbine. The steam injection configuration can improve the thermal efficiency of simple and regenerative gas-turbine cycles. In this paper, the performance characteristics of two types of regenerative steam-injection gas-turbine (RSTIG) systems are analyzed and they are compared with the performances of the simple, regenerative, water injection and steam injected gas-turbine (STIG) cycles. The thermal efficiencies of the RSTIG systems are higher than those of the regenerative, water injection and STIG systems and the specific power is larger than that of the regenerative cycle. The optimum pressure-ratio for maximum efficiency of the RSTIG systems is relatively low. Furthermore, the steam-injection configuration can be applied in the flexible heat-and-power cogeneration system and the total efficiency of the RSTIG cogeneration system reaches more than 70% (HHV).     

燃煤气的闭式 STIG 循环的热力学分析

本文将煤气化技术用于闭式注蒸汽燃气轮机循环,对以煤气化产物为燃料的闭式注蒸汽循环进行了热力学分析,并与燃煤气的开式ＳＴＩＧ循环做了比较,同时分析了回收水量的影响因素。     

Optimization of inlet air cooling systems for steam injected gas turbines

The cooling of the inlet air in gas turbines is a practice used to improve power performances. In the past, the authors suggested extending this practice to STIG turbines, using some of the heat generated in the back boiler to supply the absorption systems. Positive results have prompted further developments. For the purpose of verifying the positive effects of compression air cooling in STIG turbines, a calculation model has been developed and studied specifically for gas turbines and STIG turbines. The model has been applied to the Allison 501 KH turbine.In addition to focusing on the two traditional techniques used to cool the air of the compression system through an absorption unit and an intercooling unit, the present work emphasizes the advantages of using an ejection cooling system. The availability of exhaust heat from the STIG turbines prompted the idea of cooling through a double ejection system. Water cannot be used as a primary refrigerant in compression cooling systems because of the very low pressures that have to be reached, whereas the ejection system used for steam compression allows for the use of water. Moreover, the ejection system is relatively easy to design and construct. The use of this cooling system, enables good results to be obtained in terms of the ejection system's coefficient of performance and consequently of the STIG turbine's performance.     

高温燃料电池/燃气轮机混合循环发电技术

高温燃料电池／燃气轮机混合循环系统以其效率高、排放低的特点,在未来分布式发电和集中式大规模发电中占有重要地位。本文首先简介了高温燃料电池和先进燃气轮机的结构特点及其分类,在此基础上阐述了高温燃料电池与先进燃气轮机混合系统的基本模式,然后对适用于分布式发电和集中式发电的几种典型混合循环系统的结构和相应的流程及特点进行了详细的描述,最后给出了高温燃料电池和燃气轮机混合循环发电系统中的一些主要代表性技术以及目前研究的进展、挑战和目标。     

Solar hybrid steam injection gas turbine (STIG) cycle

Solar heat at moderate temperatures around 200 °C can be utilized for augmentation of conventional steam-injection gas turbine power plants. Solar concentrating collectors for such an application can be simpler and less expensive than collectors used for current solar power plants. We perform a thermodynamic analysis of this hybrid cycle. High levels of steam-to-air ratio are investigated, leading to high power augmentation compared to the simple cycle and to conventional STIG. The Solar Fraction can reach up to 50% at the highest augmentation levels. The overall conversion efficiency from heat to electricity (average over fuel and solar contributions) can be in the range of 40–55% for typical candidate turbines. The incremental efficiency (corresponding to the added steam beyond conventional STIG) is in the range of 22–37%, corresponding to solar-to-electricity efficiency of about 15–24%, similar to and even exceeding current solar power plants using higher temperature collectors. The injected water can be recovered and recycled leading to very low water consumption of the cycle, but a very low cost condenser is required to make water recovery feasible.