基于单耗分析法的核电机组能耗分布评价

单耗分析法是基于热力学第二定律以分析产品单耗结构作为降耗指标的能耗评价方法。核电系统遵循单耗分析方法,其能耗评价方式可以分为:标准燃料损耗化及附加单耗分布形式和标准煤耗化及其附加单耗分布形式,体现出不同标准燃料下的能耗分布状况。针对国内最新引进的第三代非能动压水堆AP1000机组进行拓展研究,在保证核电机组安全运行的前提下,提高堆芯对一回路换热温度等级,同时相应提高二回路汽轮机系统工质参数,对提高核电机组效率有显著作用;常规岛中减小蒸汽湿度,有助于降低回热系统能耗。     

积极推广热,电,冷三联供

阐述了供冷，供冷供暖，分散制冷，集中制冷和集中制冷蒸汽－热水系统；分析了热，冷联产“节电节能”应积极推广应用。     

能源结构调整的理论基础研究

针对能源结构调整优化的战略需要,基于单耗分析理论,从热力学第二定律的角度分析了不同品质燃料对能源利用第二定律效率的影响,并对几种典型能源品种的燃料(火用)进行了分析和评价.结果表明:燃料品质越高,其电量化的燃料(火用)越高,用于发电消耗的燃料就越少.提出了基于热力学第二定律的折算标准煤系数,为能源结构调整和优化配置提供了必要的理论基础.     

供热系统_单耗分析_模型

本文首先介绍了提出了理论和方法的梗概,并在此基础上建立一现代供热系统的一般化模型,针对这一模型,计算了锅炉供热、电热供热;热泵供热和热电联产供热系统中燃料的理论单耗、附加单耗和在用户终端处供热的燃料单耗。给出了供热成本的计算公式,该计算方法适于在工程中应用。     

节能量计算的第二定律方法及其应用

鉴于第一定律的节能分析方法存在的问题,本研究基于热力学第二定律,推导出节约能量计算的一般化方法,从热力学实质上揭示节约能量正比于节能技术改造带来的能源利用系统总熵产的减少。针对火电机组,给出了系统总熵产计算模型。以输入燃料一定为条件,推导出超超临界机组锅炉烟气余热回收用于加热凝结水的节约能量计算公式,进一步揭示机组总熵产的减量正比于总热损失的减量,这意味着基于热力学第二定律的节能量计算和审计可以通过改造前后的系统总体热平衡分析进行,案例分析验证了本研究提出方法的正确性和实用性。     

能源站供冷系统冷源优化配置分析研究

对能源站供冷系统蒸汽溴化锂机组和电制冷机组的冷源优化配置进行分析研究。基于DeST软件建立某区域内若干典型建筑物的能耗模拟模型,通过模拟计算得到能源站供冷系统总的全年逐时负荷。综合考虑初投资及年运行费用,采用全寿命周期成本评价指标法,分析研究能源站供冷系统中的蒸汽型双效溴化锂与电制冷冷水机组容量的优化分配,通过计算得到典型工况下得到全寿命周期成本最低的溴化锂制最优供冷比例为61.8%。在此基础上,进而分别探讨电制冷主机COP及蒸汽价格变量因子对能源站供冷系统的制冷主机容量配比的影响规律,得出溴化锂机组最优配比随电制冷主机COP值升高而下降,随蒸汽价格升高而下降的基本规律。研究成果可为能源站供冷系冷源的配置选型提供参考。     

槽式太阳能热发电系统分析

结合SEGS-VI槽式太阳能热电站参数,建立槽式太阳能热发电系统模型。以热力学第一、第二定律为理论基础,采用能量系统的白箱模型分析方法对槽式太阳能热发电系统——聚光集热子系统、换热子系统和动力子系统分别进行计算从而得到子系统各过程的耗散。最后用总能系统的白箱模型分析将子系统看作白箱,并以流连接形成白箱网络,对总能系统用能状况作出合理评价,找出系统用能过程中的薄弱环节,为系统节能提供依据。     

燃气轮机热电联供系统的应用和发展

浦东国际机场能源中心是机场规划设计时“大集中，小分散”供冷供热方案中最为关键的“集中”——供冷供热主站，其通过燃气轮机热电联供系统采用了“汽车共生，冷、热、电三联供”这一新的制冷供热方式，为这一先进技术在国内的应用迈出了坚实的一步。燃气轮机热电联供系统通过发电机，为并网处的机场用户供电，在技术上还可以向市网送电，通过余热锅炉供热，产生的电和蒸汽通过离心式制冷机组和溴化锂吸收式制冷机组供冷，为航站楼、机场当局办公楼、海关边联检楼、餐饮娱乐中心、配餐、货运、宾馆、医疗急救中心、金融中心等用户供冷供热，由此称为“三联供”。     

Analysis Model for Unit Consumption of Power Boilers and its Application

根据单耗分析理论,将锅炉各受热面的工质吸热量视为不同的热产品,分析生产这些热产品所经过的从燃料到理论燃烧温度下的烟气热流,再到实际燃烧放热温度下的烟气热流,最后到热产品具有的工质热流共3个不可逆热力学过程及其附加燃料单耗,建立了一套完整的电厂锅炉单耗分析模型;并针对某超临界机组系统及其热力参数,在热力计算的基础上,进行了锅炉单耗分析.结果表明：工质在省煤器吸热获得热流是最小的,其效率最低;从理论上证明了锅炉省煤器的概念名不副实,它的存在成为燃煤火电机组发电效率进一步提高的制约因素.     

热电冷三联产系统中制冷废热利用的研究

针对热电冷三联产系统中溴冷机排出的大量废热,提出了2种回收制冷废热的方案,并对其一次能耗综合热利用率和综合效率进行了计算与分析.结果表明:2种方案的能源利用率均得到了有效提高,在供冷/供热蒸汽量比较小时,系统相对简单的方案1优于方案2;当供冷/供热蒸汽量比增大时,方案1的一次能耗综合热利用率和综合效率变化极小,而采用热泵的方案2的一次能耗综合热利用率和综合效率均先提高后降低,且在供冷/供热蒸汽量比为3.3 k时达到最大值.     

Comparative study of different solar cooling systems for buildings in subtropical city

In recent years, more and more attention has been paid on the application potential of solar cooling for buildings. Due to the fact that the efficiency of solar collectors is generally low at the time being, the effectiveness of solar cooling would be closely related to the availability of solar irradiation, climatic conditions and geographical location of a place. In this paper, five types of solar cooling systems were involved in a comparative study for subtropical city, which is commonly featured with long hot and humid summer. The solar cooling systems included the solar electric compression refrigeration, solar mechanical compression refrigeration, solar absorption refrigeration, solar adsorption refrigeration and solar solid desiccant cooling. Component-based simulation models of these systems were developed, and their performances were evaluated throughout a year. The key performance indicators are solar fraction, coefficient of performance, solar thermal gain, and primary energy consumption. In addition, different installation strategies and types of solar collectors were compared for each kind of solar cooling system. Through this comparative study, it was found that solar electric compression refrigeration and solar absorption refrigeration had the highest energy saving potential in the subtropical Hong Kong. The former is to make use of the solar electric gain, while the latter is to adopt the solar thermal gain. These two solar cooling systems would have even better performances through the continual advancement of the solar collectors. It will provide a promising application potential of solar cooling for buildings in the subtropical region.     

Techno-economic performance analysis of solar cooling systems

Vapour absorption cooling systems, powered by solar thermal energy, are now commercially manufactured in sizes ranging from 1.5 to over 20 RT (one refrigeration ton = 3.51 kW of cooling). The needed thermal energy at appropriate temperature potential can either be provided by solar thermal collectors or else from a solar pond. The paper gives the assessment criteria and results for technical and economic evaluation of the performance of absorption chiller using a solar pond. These results, based on Kuwait's environmental data and costs, have been compared with three alternate cooling systems, namely:

• 1 Solar thermal collector absorption cooling system.
• 2 Solar photovoltaic cooling system.
• 3 Standard vapour compression cooling system.

The criteria, used for performance evaluation of the solar cooling systems on a technical basis, consists of assessing the extent to which such systems can make a positive contribution in a conserving fossil fuel. This is done by first estimating the total electrical energy needed by the standard system (defined in para. 3 above) to produce one unit of cooling output. Solar cooling systems are then analysed and compared with a standard system to establish their electrical energy saving or generation capability, after accounting for the parasitic electrical energy used in pump/fan motors and equivalent energy needed for the production of soft water (used-up in the cooling tower) from seawater desalination. The economic analysis considers the cost and life of subsystems and that of the electrical and water desalination plants to arrive at the unit cooling cost. The unit cooling is defined as the ratio of amortized capital investments plus operation and maintenance costs over the year and the total yearly cooling production by the system. The results show that the solar pond absorption cooling system is the closest competitor to the conventional cooling system.     

过冷式小型冰蓄冷系统(火用)分析

通过对过冷式小型冰蓄冷系统火用分析模型的建立,采用[火用]分析的方法,揭示了小型过冷式冰蓄冷系统的能量转换的薄弱环节以及过冷度对各部件[火用]损失系数和系统火用效率的影响。分析了减少火用损失的途径,节约能源。并为系统的改进和优化提供有力的理论参考。     

高铁客运站分布式多能源系统供能协同优化策略研究

为解决传统高铁客运站供能系统中能源利用率较低的问题,以日运行购气费用和购电费用最优为优化目标,以系统运行过程中实时能量平衡为约束条件,以可再生能源出力和吸收式制冷占比为优化变量,建立多能源协同供能的分布式能源系统,并将该模型应用于北方某高铁客运站,分析可再生能源的利用率、制冷系统中可再生能源电出力的电制冷占比以及电网出力的节电率。仿真计算结果表明,分布式能源系统的使用提高了可再生能源的利用率,其中风电机组出力占其出力极限的96.5%,光伏机组出力94.7%;相比于参比系统,分布式能源系统的成本节约率为12.5%;电制冷占比为13%;电网的节电率为53.9%。     

双效固体吸附制冷技术在热电厂集中供冷中的应用研究

采用双效固体吸附式制冷技术开发了热电厂新型集中供冷系统,该系统结构简单,性能可靠,投资低,耗电少,无污染,不但可为全厂提供空调用冷,而且可大幅度提高电厂机组热经济性,具有显著的节能与环保效果。     

热电冷联产经济效益分析

以热电冷联产系统的供电煤耗,燃料节约量,当量热力系统作为评价标准,对热电冷联产系统的节能效益进行了分析与研究,并提出了临界供电煤耗概念,作为判断在热电冷联产系统中节能的条件。     

Thermoeconomic optimization of an ice thermal storage system for gas turbine inlet cooling

The gas turbine power output and efficiency decrease with increasing ambient temperature. With compressor inlet air cooling, the air density and mass flow rate as well as the gas turbine net power output increase. The inlet cooling techniques include vapor or absorption refrigeration systems, evaporative cooling systems and thermal energy storage (TES) systems. In this paper the thermoeconomic analysis of ice (latent) thermal energy storage system for gas turbine inlet cooling application was performed. The optimum values of system design parameters were obtained using genetic algorithm optimization technique. The objective function included the capital and operational costs of the gas turbine, vapor compression refrigeration system, without (objective function I) and with (objective function II) corresponding cost due to the system exergy destruction. For gas turbines with net power output in the range of 25-100 MW, the inlet air cooling using a TES system increased the power output in the range of 3.9-25.7%, increased the efficiency in the range 2.1-5.2%, while increased the payback period from about 4 to 7.7 years.     

火电机组热力系统成本分布通用矩阵方程

基于成本理论建立了热力系统局部成本分析通用模型及火电机组热力系统成本分布的通用矩阵方程,并对某600MW机组的热力系统进行实例计算与分析,得到了额定工况下独立流的单位成本.结果表明：该方程构造规范,适用于各种不同的热力系统,可以用于分析热力系统中存在的共性规律;对于具体的热力系统,通过将一些必要的矩阵元素代入方程中,可得到独立流的单位成本和单位成本的分布规律,为机组的节能降耗提供指导;如果对方程进行进一步的微分运算分析,还可求出一些因素变化对单位成本影响的敏感度.     

Development of a combined system based on a PEMFC and hydrogen storage under different conditions equipped with an ejector cooling system

In the current work, thermodynamic examination for cogeneration of electricity and cooling based on a polymer exchange membrane (PEM) fuel cell was carried out. To the waste energy in the fuel cell, an absorption refrigeration unit is employed in two modes with ejector and without ejector. This system includes a PEM-FC, an absorption refrigeration unit, a hydrogen storage tank, an ejector, and an air compressor. The produced thermal energy in the fuel cell is received entirely by a working fluid and is given to the absorption chiller generator. The system simulation was carried out from two perspectives of energy and fuel saving. Findings showed that the energy efficiency of the combined cooling and power (CCP) unit and the CCP system equipped with the ejector (CCP-E) was 63.72% and 78.33%, respectively. It indicated that adding the ejector to the system increases the energy efficiency of the system by 23%. The fuel economy percentages of the CCP system and CCP-E were 44.43% and 45.9%, respectively. The results also showed that adding the ejector in the refrigeration system increases the system performance by up to 44%. The presence of the ejector causes the working fluid flow in the evaporator to increase with the suction of the secondary flow, and the cooling capacity increases significantly. Moreover, with increasing generator and evaporator pressure, the suction ratio of the cooling system equipped with the ejector decreases and increases, respectively.     

联产供冷与电力供冷能耗比较分析

文中将两种供冷能耗比较分解成用电煤耗差、用热煤耗量、增加产汽用电煤耗量三部分进行分析，按照热量法得出在目前一般情况下联产供冷比电力供冷通常费能和定性定量结论，为全面研究比较热电冷联产与分产的能耗奠定一个基础。