循环灰为热载体的移动床煤热解室数学模型

以循环灰为热载体的移动床煤热解室,是煤气－蒸汽联产系统中的关键设备,基于煤的干燥与热解子模型,非烧结多孔介质内流动与传热理论,以及固体间接触导热等理论,结合“限制粒径”判据,建立了移动床煤热解室内煤热解过程的综合数学模型,并利用模型对龙口褐煤的热解过程进行了仿真计算,得到了满意的结果。     

对CFB燃烧_煤热解多联产工艺过程的开发

在处理量为1kg煤的间歇式固体热载体热解装置上,以高挥发份烟煤为原料,石英砂作热载体,进行热解特性评价实验。结果表明,提高混合热解温度,气体产率有所增加。温度高于560℃时焦油产率可达9%(wt)～11%(wt)。通过模拟炉前低温干馏过程,以高硫的坪石煤为原料,发现循环灰具有明显的固硫作用,热解产生的大部分气相硫被固定在灰中。同时,结合实验室前期的研究结果以及正在进行的多联产中试试验,对CFB燃烧/煤热解多联产工艺过程开发中的关键技术问题的解决方案,如组合式U型返料器开发、反应器压力的控制方式、体系平衡关系的建立等进行了探讨。     

我国煤热解多联产技术的发展概况

目前煤热解多联产已成为一项提高煤炭资源综合利用率的高新技术,是未来洁净煤主要的发展方向.以煤热解为核心的多联产工艺已成为我国煤炭利用的主要途径,通过煤热解多联产技术可有效地将煤炭化工和电力工业结合起来,不仅解决了煤炭利用率低下、化工产品制造成本高等问题,而且对我国的环境保护有着重要影响.介绍了国内外煤热解多联产工艺的研究状况,并对国内几种典型的煤热解多联产工艺进行了评述,总结了当前煤热解多联产工艺的优缺点和主要发展方向.     

以煤热解为基础的多联产系统的热效率分析

多联产作为高效、环保的化工能源系统,特别是以联产甲醇和电为代表的多联产是最典型的多联产系统,具有显著的节能功能。本文以热力学方法研究了以煤热解为基础的多联产系统的热效率,进一步将联产和分产进行了节能效果比较。     

以煤气化为核心的多联产技术

以煤气化为核心的多联产能源系统以煤、渣油或石油焦为原料,将其气化后生产一氧化碳和氢气为主要成分的合成气,合成气极易脱除二氧化硫等。干净合成气可作为原料进行热、电、气、化联产,即在发电的同时,联产包括液体燃料在内的多种高附加值的化工产品、城市煤气以及工艺过程热。合成气经过进一步的转化反应和气体分离,可得到氢气和二氧化碳。二氧化碳可以直接分离出来,进行综合利用和埋存。多联产系统的实质是多种产品生产过程的优化耦合。优化耦合之后的产品生产流程可以简化,从而减少基本投资和运行费用,降低各个产品的成本。     

Performance analysis of an irreversible cogeneration heat pump cycle

An irreversible heat engine-driven vapour compression and absorption heat pump system is considered as a cogeneration cycle. The effects of thermal resistances and internal irreversibilities on the coefficient of performance (COP) of this cogeneration cycle were investigated using finite-time thermodynamic approach. An improved equation for the COP of the system under consideration was obtained. The results obtained here may serve as a good guide for the evaluation of existing real cogeneration heat pumps or provide some theoretical bases for the optimal design of future cogeneration heat pumps. © 1998 John Wiley & Sons, Ltd.     

Application of a chemical heat pump to a cogeneration system

The feasibility of a proposed system that combines a magnesium oxide/water chemical heat pump and a diesel engine as a cogeneration system is discussed based on experimental results. The combined system is intended to utilize the waste heat discharge from the engine by means of the chemical heat pump and to level the heat supply load of the engine, allowing enhanced energy utilization. The thermal performance of the chemical heat pump in the cogeneration system is estimated based on the results of a packed‐bed experiment. The estimation indicates that by storing the waste heat from the engine during low demand periods, the cogeneration system can produce more than several times the standard thermal output of the diesel engine during peak demand periods. Copyright © 2001 John Wiley & Sons, Ltd.     

燃气轮机在热电联产工程中的应用状况分析

燃气轮机是21世纪乃至更长时间内能源高效转换与洁净利用系统的核心动力装备.介绍了燃气轮机的发展现状及其在热电联产工程中的应用,简述了联合循环和简单循环燃气轮机电厂的基本组合方式,并列举了目前应用在热电联产工程中的几种主要的燃气轮机.阐述了燃气轮机相对于常规火电机组的优点,分析了影响燃气轮机在热电联产工程中推广的因素,并对我国燃气轮机的发展前景进行了展望.     

Performance simulation of heat recovery steam generators in a cogeneration system

The performance simulation of heat recovery steam generators in a cogeneration system has been investigated to see the effect of pinch and approach points on steam generation and also on temperature profiles across the heat recovery steam generator. The effects of operating conditions on steam production and also on exit gas temperature from the heat recovery steam generator are discussed. Low pinch point results in improved heat recovery steam generator performance due to reduced irreversibilites. The supplementary firing enhances the steam production. © 1998 John Wiley & Sons, Ltd.     

论“热电联产”型燃气—蒸汽联合循环的特性

探讨了“热电联产”型燃气－蒸汽联合循环中热电联产的各种组合方案及其特性,剖析了燃气轮机热电联产系统特性图的物理含义,提出了热电联产型联合循环装置的各种组合方案。     

Energy supply performance and environmental load‐reduction effect of a cogeneration system for an apartment building using distributed heat storage technology

In order to make distributed generation systems for apartment buildings economically viable, it is essential to develop an efficient and low‐cost heat supply system. We are developing a new cogeneration system (Neighboring CoGeneration system: NCG system). The key concept of this system is to install a heat storage unit for the hot water supply, floor heating, and bath heating in each house, and to connect the heat storage units by a single‐loop hot water pipe. The system leads to time leveling of the total heat supply and reduced installation costs. Furthermore, it is expected that the cogeneration can operate according to electrical demand because of the large heat storage capacity of the system. In this study, a dynamic simulation model is developed to evaluate the performance and environmental load‐reduction effect of the NCG system for 50 households. The results show that the NCG system can supply sufficient heat for peak demand in winter and reduce annual CO₂ emissions by 23% on average. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res, 42(8): 745–757, 2013; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20376     

基于大规模热电联产的低碳城市建设方案研究

在满足城市发展需求的同时,如何能够有效控制碳排放,是中国必须面对的现实问题,也是应对全球气候变化的重要举措。为实践上述举措,在辽宁省营口市进行了以大规模热电联产为主要实施手段的低碳城市建设研究:在对整个市域范围内的热力与电力需求进行预测的基础上,结合对现有工业热源的改造,规划并建设了若干大型燃煤热电厂,以提高整个区域的能源利用效率,减少碳排放,为未来安装集中式碳捕集装置提供便利条件。该研究不仅是构建中国特色低碳城市的一次大胆尝试,而且也为发展中国家的节能和碳减排工作提供了有益参考。     

有机热载体锅炉尾部高效余热利用装置的设计与应用

有机热载体锅炉广泛应用于纺织、印染行业,由于高温定型和染整的特殊工艺以及有机热载体锅炉的构造和运行原理造成其尾部排烟温度在300℃左右,产生巨大的热能浪费。为减少热能损失,通过高温烟气的余热回收利用,提高有机热载体锅炉的综合热效率,可实现节能降耗和减排。本课题运用热管技术设计研制了结构合理、操作方便、高效的有机热载体锅炉尾部高温烟气的回收再利用装置。     

Study on waste heat recovery from exhaust smoke in cogeneration system using woody biomass fuels

In recent years, fossil fuels such as petroleum, coal, and natural gas have become limited resources. In addition, bad effects caused by excessive carbon dioxide (CO₂) emissions have now begun destroying our global environment seriously. Since current living and economical standards depend strongly on the fossil fuels, it is necessary to realize a new society that utilizes biomass as one of major sources of energy. In this background, we manufactured a practical Stirling engine using woody biomass fuels for the first time in Japan in 2005. Further we proposed a unique cogeneration system with the Stirling engine that uses woody biomass fuels such as sawdust, firewood, and wood pellets. In this cogeneration system, 43% of the input energy is wasted as heat loss from the exhaust smoke into the atmosphere. Therefore we tried to recover the waste heat by using a thermoelectric conversion module in this study. In this report, the results of basic performance test and demonstration experiment as a cogeneration system combined the waste heat recovery with a power generating system are reported. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20390     

A district heating system based on absorption heat exchange with CHP systems

In order to decrease the energy consumption of large-scale district heating systems with cogeneration, a district heating system is presented in this paper based on absorption heat exchange in the cogeneration system named Co-ah cycle, which means that the cogeneration system is based on absorption heat exchange. In substations of the heating system, the temperature of return water of primary heat network is reduced to about 25°C through the absorption heat-exchange units. In the thermal station of the cogeneration plant, return water is heated orderly by the exhaust steam in the condenser, the absorption heat pumps, and the peak load heater. Compared with traditional heating systems, this system runs with a greater circuit temperature drop so that the delivery capacity of the heat network increases dramatically. Moreover, by recovering the exhausted heat from the condensers, the capacity of the district heating system and the energy efficiency of the combined heat and power system (CHP system) are highly developed. Therefore, high energy and economic efficiency can be obtained.