《相变储能专刊:从材料到系统集成与应用》特约主编寄语CSCD

储能技术有多种,其适用范围各异,热能存储(储热/储冷)技术是其中之一.目前全球储能装机容量约为22.4GW,其中抽水蓄能约为91％,其余9％的份额中,热能存储装机容量约为65％——体现了热能存储的重要性.如下图所示,热能存储技术可分为化学热能存储和物理热能存储两大类,其中化学热能存储技术可分为基于可逆化学反应和吸附/吸收两种,而物理热能存储技术则包括显热和潜热(或相变)热能存储两种.     

基于生物质能的MDF生产线综合供能系统

热能中心是一种基于生物质能的综合供能系统,可以向MDF(中密度纤维板)生产线提供所需的热能和电能.文章介绍了热能中心的基本原理、系统组成和工艺流程,以年产20万m<'3>的MDF生产线热能中心为例,重点分析了热能中心的节能效益和环保效益.     

热能利用的评价及其意义

<正> 一、热能利用评价的基本理论目前对热能利用的评价依据是:对某一系统或某一设备进行能量平衡。能量平衡的方法有两类:一类是以热力学第一定律为基础的能量数量分析法,称热平衡分析法;另一类是以热力学第二定律为基础的能量质量分析法,称(火用)平衡分析法。 1.热平衡分析法中的技术指标热力学第一定律阐述;各种形式的能量在传递和转换过程中,总量守恒。对热能而言: 输入的热能=有效利用热能+损失热能热效率=有效利用热能/输入的热能×100％     

谈小型锅炉使用单位的节能减排

如何提高小型锅炉的使用单位的使用管理水平是节能减排的重点研究的课题,热能从生产到使用大体可以分成热能的产生环节、热能的使用环节、热能输送环节三个部分,着重就以上3个环节中可能出现或经常出现的问题加以分析,就可能出现的问题和解决措施进行探讨,着重分析了热能的产生环节,希望对中国小型锅炉的使用单位的节能减排有所帮助.     

太阳能热发电

太阳能热发电是先将太阳能转化为热能．再将热能转化成电能。它有2种转化方式。1种是将太阳热能直接转化成电能;如半导体或金属材料的温差发电,真空器件中的热电子和热电离子发电,碱金属热电转换,以及磁流体发电等。     

太阳能集热器

太阳能集热器的定义是：吸收太阳辐射并将产生的热能传递到传热介质的装置。这短短的定义却包含了丰富的含义：太阳能集热器是一种装置;太阳能集热器可以吸收太阳辐射;太阳能能集热器可以产生热能;太阳能集热器可以将热能传递到传热介质。     

内燃机的分类方法及分类

1.热力发动机及其类别将热能转变为机械能的发动机称为热力发动机(简称热机)。热机的热能是由燃料燃烧后产生的。热机有内燃机和外燃机之分。内燃机是燃料和空气的混合物在发动机内部燃烧,并且放出热能而作功的原动机;外燃机是燃料和空气的混合物在发动机外部燃烧,并放出热能而作功的原动机。外燃机一般分为蒸汽机和蒸汽轮机两种。     

热能存储及转化技术进展与展望

能量的消耗、转换与利用伴随着人类社会的各种生产及生活活动.随着社会的持续发展,世界范围内的能源危机与环境污染问题对能源的高效合理利用及存储技术提出了更高要求.热能是最常见及最重要的能量形式,深入分析目前热能的主要来源、利用、存储方式及特点,促进热能的合理高效利用对当代社会的可持续发展至关重要.本文主要从热能来源形式及利...     

节能检测与成份自动分析

<正> 一、节能管理实行仪器仪表化的重要意义煤、油、天然气等能源物资是实现我国四个现代化极其重要的物资条件。党和国家对于能源的开发及合理利用十分重视。在我国,能源利用效率很低,主要表现在热能的浪费上。这就要求热能的使用部门加强节能管理,改造热工设备,改进工艺操作,提高热能利用率。热能利用是一门科学,必须采用必要的     

氢能知识系列讲座(7)氢内燃机和氢燃料

氢气的常规利用方式主要是两种,一种是通过电化学方法,利用我们前两讲介绍的"燃料电池"将氢的化学能变为电能和热能;另一种方式是通过热化学方式,即燃烧氢,将化学能变成热能或动能。例如,用锅炉将氢能变成热能,用"内燃机"将氢能变成动能。本讲就是介绍氢内燃机。"内燃机"是一种动力机械,它是通过燃料在汽缸内燃烧,将放出的热能直接转换为动力的热力发     

Evaluation of retrofitting a conventional natural gas fired boiler into a condensing boiler

The exit flue gas temperature of a conventional gas fired boiler is usually high and a great amount of heat energy is lost to the environment. If both sensible heat and latent heat can be recovered by adding a condensing heat exchanger, the efficiency of the boiler can be increased by as much as 10%. In this paper, based on combustion and heat transfer calculations, the recoverable heat and the efficiency improvement potential of different heat recovery schemes at various exit flue gas temperatures are presented by performing design calculations. The payback period method has been used to analyze the feasibility of retrofitting a conventional gas fired boiler into a condensing boiler in a heating system in detail. The results show that the most economical exit flue gas temperature is 40–55 °C when a conventional natural gas fired boiler is retrofitted into a condensing boiler simply by adding a condensing heat exchanger. It is feasible to use the return water of a heating system as the cooling medium of the condensing heat exchanger because the return temperature varies with the ambient temperature and is lower than the dew point of the water vapor in the flue gas in most periods of a heating season in some regions, which has been verified by retrofitted case.     

Analysis of the impact of heat-to-power ratio for a SOFC-based mCHP system for residential application under different climate regions in Europe

In this paper, the ability of a micro combined heat and power (mCHP) system to cover the heat and electricity demand of a single-family residence is investigated. A solid oxide fuel cell based mCHP system coupled with a hot water storage tank is analyzed. The energy profiles of single-family households in different European countries are evaluated. The range of Heat-to-Power Ratio for the SOFC-based mCHP System of 0.5–1.5 shows good agreement with the hot water, space heating and electricity demand during the warm seasons across Europe. This suggests that the fuel cell system should be sized according to the summer energy demand. The winter energy demand shows a Heat-to-Power Ratio which cannot be covered by the mCHP unit alone. To ensure that the mCHP system meets both the thermal and electrical energy demand over the entire year, an auxiliary boiler and a hot water storage tank need to be coupled with the mCHP unit. It is further noted that the size of the auxiliary boiler should match the larger winter space heating demand. In contrast, the hot water tank volume should be sized according to the warm season space heating requirement, when space heating is not required but electricity and hot water are still in demand. This maximizes the running time of the fuel cell, and thus the economic and environmental benefit of the system, without wasting produced heat.     

矸石砖厂排烟废热回收系统研究

叙述了利用高效热风换热器,将矸石砖厂排烟、排潮回风中蕴含的热能交换到循环水中,实现为热泵系统提供稳定的低温热源,替代传统的燃煤锅炉,为冬季采暖、井筒防冻及洗浴提供热水的节能改造情况,提出,热泵系统联合排烟热能回收系统的研究思路、设计方案.     

Optimization of a thermal storage unit combined with a biomass boiler for heating buildings

The performance of a boiler with a built-in thermal storage unit is presented. The thermal storage unit is an insulated water tank that absorbs surplus heat from the boiler. The stored heat in the thermal storage unit makes it possible to heat even when the boiler is not operating, thus increasing the heating efficiency. A system with three components is described. The model of the system and the mathematical model were made using the TRNSYS program package and a test reference year (TRY). The degree of efficiency, which optimizes the thermal storage volume and the heating power of the boiler, was determined. The thermal storage must also ensure that the heat is stored at the highest possible exergy level, and complete mixing of the water is a condition for optimizing the thermal storage. The matching of the boiler’s heating capacity with the thermal storage unit ensures a supply of heat even when the boiler is not operating.     

热(汽、水)冷联供及其效益分析

根据山东省的地理位置和气候特点,论述了一种在原冬季供热设备的基础上用大型供热锅炉或热电厂中的锅炉,结合溴化锂吸收式制冷机向用户供冷的方案,并从能耗水平、节能效益、节电效益、热电厂的增电效益、设备投资、运转费用和社会效益等几个方面阐述了这种热（汽、水）冷联供的优越性,认为这种热（汽、水）冷联供方式是协调大中城市热电厂和大型集中供热锅炉冬夏负荷不均、充分利用现有供热设备、为夏季空调提供冷源的一种有效方式。     

Fuzzy controlled central heating system

In this paper a comparison study was carried out in order to understand how two different systems, classical and fuzzy logic control of central heating affect the economy and comfort of private homes or offices. Also a literature review was done to help decide which one of these systems is more effective. The objective of the fuzzy controller heating system is to estimate the actual heat requirement of the house. It uses a total of five inputs, four of which are derived from energy consumption curve, using conventional digital filtering techniques; the fifth is the average outdoor temperature, whereas, the classical control system burns diesel type fuel in its furnace to heat the water supply (boiler). From the boiler, the hot water is distributed by a pipe system to the individual radiators in the house. Thereby, it is shown that the fuzzy controlled heating system is more effective, also it maximizes the economy and the comfort of the consumer. Copyright © 2002 John Wiley & Sons, Ltd.     

家用壁挂式燃气炉供暖的应用探讨

天然气是优质洁净能源,采用家用壁挂燃气炉供暖不仅减少了环境污染,而且一炉多用,不仅可以供暖,同时也可以提供生活热水,而且供暖的自动化程度高。经过分析表明,采用家用壁挂式燃气炉供暖比按供热面积收费的集中供热方式和热泵空调供暖方式经济。     

A novel hybrid heat-pipe solar collector/CHP system—Part II: theoretical and experimental investigations

A theoretical analysis has been carried out to investigate the thermodynamic and heat transfer characteristics of a hybrid heat pipe solar collector/CHP system based on the assumption that the system operates on a typical Rankine cycle. Experimental testing of the prototype was also carried out using two types of turbine units. The variation of refrigerant pressures and temperatures, hot water temperatures in the collector and boiler systems, as well as chill water temperatures were recorded. The results were used to estimate the heat from the boiler and the solar collectors, the electricity and hot water generation (indicated as kW energy) from the CHP operation and the gas consumption of the system. The modelling and experimental results were compared for the impulse-reaction turbine system, and a simple analysis of the energy and environmental benefits of the system was carried out. The analysis indicated that the proposed system would save primary energy of approximately 3150 kWh per annum compared to the conventional electricity and heating supply systems, and this would result in reduction in CO₂ emission of up to 600 tonnes per annum. The running cost of the proposed system would also be lower than conventional heating/power systems.     

采暖用燃气热水锅炉增效方式探讨

以采暖用燃气热水锅炉为分析背景,通过介绍锅炉运行过程中能源消耗情况,分析了每个环节的节能潜力,得出,降低排烟热损失、提高运行控制水平的节能潜力较大,而降低锅炉排污热损失、降低燃气热水锅炉系统补水率有一定的节能潜力。     

超临界“W”火焰炉关键技术应用

针对燃用高硫高灰无烟煤超临界"W"火焰锅炉投产后暴露出来的燃烧稳定性差、锅炉受热面热偏差严重、NO_x排放浓度高、锅炉受热面结焦腐蚀、启动油耗偏大等影响机组安全稳定运行、高效清洁燃烧等问题,开展超临界"W"火焰锅炉设计优化、燃烧及制粉系统制造运行优化、锅炉热面在线监测技术研究、锅炉受热面防结焦防高温腐蚀技术材料研究、无烟煤节油点火技术开发等关键技术研究与应用,有效解决了超临界"W"火焰锅炉安全稳定、高效清洁燃烧的技术难题。