溴化锂吸收式制冷机采用塑料传热管的研究

提出了在溴化锂吸收式制冷机中采用塑料传热管代替铜传热管,以解决传热管腐蚀及其引起的冷量衰减问题。以1台制冷量为35kW的溴冷机为例,对采用塑料传热管的溴冷机与传统铜管溴冷机相关部件的参数进行比较。通过对溴冷机的传热面积、管道阻力的计算和安全强度的校核,发现采用塑料传热管的溴冷机在技术上是可行的。     

溴化锂吸收式冷暖水机组及投资决策分析

本文简述了溴化锂吸收式冷暖水机组的优点和目前我国国内溴冷机的生产、销售情况，运用了一系列专门的方法对溴冷机生产投资决策作了较为具体的可行性分析，并提出了应注意的有关问题。     

在溴化锂制冷机上应用板式换热器的可行性分析

在溴化锂制冷机上应用板式换热器的可行性分析陈亚平东南大学动力系溴化锂吸收式制冷机（简称溴冷机）具有节能、节电、无公害等优点，是取代氟利昂压缩式制冷机作为中央空调主机的最佳形式。目前溴冷机的结构形式都采用管壳式，大多用铜管作传热面。国外的先进技术也主要...     

烧结余热发电技术应用与改造

对现有烧结余热发电机组存在的问题进行分析,指出烟气温度低、回风管布置不合理、环冷机密封不严、循环风机磨损等是环冷机余热利用效率低的主要原因,进而进行取烟点优化、密封系统改造、回风管路优化。现场检测数据表明,该改造方案有效提高环冷机余热利用率,同时烟气含尘量明显减小,循环风机蜗壳和转子叶轮磨损情况得到改善,每年节省检修成本40万元,增加发电收入120万元。     

烧结环冷机低温余热锅炉的优化设计

针对现有烧结环冷机低温余热锅炉技术状况,通过对烟风系统和热力系统、余热锅炉结构优化,降低投资成本,提高余热利用效率。     

链篦机-回转窑系统中环冷机的质能平衡与节能分析

在总结链篦机-回转窑球团生产工艺特点的基础上,对首钢矿业公司链篦机-回转窑系统中的环冷机进行了质能平衡测试,得到了环冷机的风量平衡、物料平衡和能流平衡。测试表明:环冷机平均产量274.24 t/h,热回收率达到93.91%,成品球质量、冷却温度等均满足生产要求。此外,还针对环冷机运行中存在的问题,提出了优化改造的建议。     

大通道封闭板型传热元件制造工艺解决方案探讨

本文主要介绍电站锅炉回转式空气预热器大通道封闭板型传热元件的制造技术,介绍该类板型制造技术的难点,重点探讨该类板型制造工艺的解决方案和取得的初步成果。     

热水余热制冷技术在塔河油田溴冷机中央空调上的应用

对塔河油田发电一厂余热锅炉高温段出水夏季热用户不足,存在热能浪费,难以寻找突破口以增加热用户等问题,通过应用热水余热利用技术,设计热水型溴化锂制冷机中央空调系统,取代已有直燃型溴冷机系统,节约了燃气费、电费等。在夏季热用户锐减形势下增加了热用户,确保余热锅炉平稳运行。完成了中石化"能效倍增计划"2014年立项项目之一。     

烧结环冷机余热电站运行特性研究

提高吨烧结矿余热发电量是环冷机余热电站优化设计与运行的目标。以唐钢炼铁厂北区烧结环冷机余热电站为例,通过建立以质能平衡为基础的热力计算模型和以发电净功率为目标函数的优化调度模型,研究了发电净功率随热废气温度和主蒸汽压力等参数的变化规律。统计分析了吨烧结矿发电运行指标的变化规律,确定了环冷机余热电站吨烧结矿发电指标的选择范围。其研究结果可为烧结环冷机余热电站运行参数调整和装机容量选择提供参考依据。     

违章操作造成柴油机故障分析

由于违章操作而造成的柴油机故障，在柴油机的故障中占有很大比例，主要表现在以下几方面：ａ．柴油机冷机启动后猛轰油门。有些驾驶员在启动柴油机后总爱轰几脚油门，这是一种坏毛病。因为发动机停放一段时间后，各摩擦表面润滑油已流失，而冷机启动时，由于温度低，机油...     

Transient simulation and parametric study of solar-assisted heating and cooling absorption systems: An energetic,economic and environmental (3E) assessment

This paper presents energetic, economic, and environmental (3E) analyses of four configurations of solar heating and cooling (SHC) systems based on coupling evacuated tube collectors with a single-effect LiBr–H₂O absorption chiller. In the first configuration (SHC1), a gas-fired heater is used as the back-up system, while a mechanical compression chiller is employed as the auxiliary cooling system in the second configuration (SHC2). The capacity of the absorption chiller is designed based on the maximum building cooling load in these configurations. The third and fourth configurations (SHC3 and SHC4) are similar to SHC2, but the absorption chiller size is reduced to 50% and 20%, respectively. The results show that the highest primary energy saving is achieved by SHC2, leading to a solar fraction of 71.8% and saving 54.51% primary energy as compared to a reference conventional HVAC system. The economic performance of all configurations is still unsatisfactory (without subsidies) due to their high capital costs. However, if a government subsidy of 50% is considered, the results suggest that SHC4 can be economically feasible, achieving a payback period of 4.1 years, net present value of 568,700 AUD and solar fraction of 43%, contributing to 27.16% decrease in the plant primary energy consumption.     

Solar space heating and cooling for Spanish housing: Potential energy savings and emissions reduction

An experimental solar energy facility was designed to meet as much of the heating demand in a typical Spanish dwelling as possible. With a view to using the facility during the summer and preventing overheating-induced deterioration of the solar collectors in that season of the year, an absorption chiller was fitted to the system to produce solar-powered air conditioning. The facility operated in solar space heating mode in the winter of 2008–2009 and in cooling mode during the summer of 2008. The design was based on a new type of flat plate vacuum solar collectors that delivered higher efficiency than conventional panels. This type of collectors can reach temperatures of up to 110 °C in the summer and up to 70 °C on the coldest winter days. The solar facility comprised a 48-m² (with a net area of 42 m²) solar collector field, a 25-kW plate heat exchanger, a 1500-l storage tank, a 4.5-kW (Rotartica) air-cooled absorption chiller and several fan coils. The facility was tested by using it to heat and cool an 80-m² laboratory located in Madrid. As the average area of Spanish homes is 80 m², the findings were generally applicable to national housing. The solar facility was observed to be able to meet 65.3% of the space heating demand. For air conditioning, the system covered 46% of the demand, but with high indoor temperatures. In other words, the collector field was found to be able to air condition only half of the home (40 m²). Lastly, the savings in CO₂ emissions afforded by the use of this facility compared to conventional air conditioning were calculated, along with its amortisation period. These results have been extrapolated calculating the potential energy savings and emissions reduction for all the Spanish households.     

Experience with fully operational solar-driven 10-ton LiBr/H2O single-effect absorption cooling system in Thailand

A solar-driven 10-ton LiBr/H₂O single-effect absorption cooling system has been designed and installed at the School of Renewable Energy Technology (SERT), Phitsanulok, Thailand. Construction took place in 2005, after which this system became fully operational and has been supplying cooling for our main testing building's air-conditioning. Data on the system's operation were collected during 2006 and analyzed to find the extent to which solar energy replaced conventional energy sources. Here, we present these data and show that the 72 m² evacuated tube solar collector delivered a yearly average solar fraction of 81%, while the remaining 19% of thermal energy required by the chiller was supplied by a LPG-fired backup heating unit. We also show that the economics of this cooling system are dominated by the initial cost of the solar collector array and the absorption chiller, which are significantly higher than that of a similar-size conventional VCC system.     

A solar thermal cooling and heating system for a building: Experimental and model based performance analysis and design

A solar thermal cooling and heating system at Carnegie Mellon University was studied through its design, installation, modeling, and evaluation to deal with the question of how solar energy might most effectively be used in supplying energy for the operation of a building. This solar cooling and heating system incorporates 52 m² of linear parabolic trough solar collectors; a 16 kW double effect, water-lithium bromide (LiBr) absorption chiller, and a heat recovery heat exchanger with their circulation pumps and control valves. It generates chilled and heated water, dependent on the season, for space cooling and heating. This system is the smallest high temperature solar cooling system in the world. Till now, only this system of the kind has been successfully operated for more than one year. Performance of the system has been tested and the measured data were used to verify system performance models developed in the TRaNsient SYstem Simulation program (TRNSYS). On the basis of the installed solar system, base case performance models were programmed; and then they were modified and extended to investigate measures for improving system performance. The measures included changes in the area and orientation of the solar collectors, the inclusion of thermal storage in the system, changes in the pipe diameter and length, and various system operational control strategies. It was found that this solar thermal system could potentially supply 39% of cooling and 20% of heating energy for this building space in Pittsburgh, PA, if it included a properly sized storage tank and short, low diameter connecting pipes. Guidelines for the design and operation of an efficient and effective solar cooling and heating system for a given building space have been provided.     

太阳能空调综合系统在住宅小区应用的可行性探讨

经济性是制约太阳能空调普及推广应用的难题。文中介绍了一种太阳能空调和热水站综合系统方案，即在居民住宅楼的屋顶布置太阳能集热器阵，结合地源水低温热源系统，建设全年供应全体住户生活热水的太阳能热水站，以及夏季和冬季供应顶一、二层住户空调冷、热水的综合系统．提出了一种双效与单效耦合的板壳式溴化锂吸收式制冷机循环方案，白天日照时段采用双效循环运行并进行蓄热，而在其余时段切换为单效循环利用蓄热运行。该方案不仅效率高、而且其单位体积蓄能罐的蓄能密度极大，可实现无需用辅助能源而完全靠太阳能进行昼夜空调。由于综合利用系统中集热器的投资费用被所有热水用户分摊，空调用户的投资可很快从节省的电费中得到回收。     

Introducing an integrated SOFC,linear Fresnel solar field,Stirling engine and steam turbine combined cooling,heating and power process

A new integrated combined cooling, heating and power system which includes a solid oxide fuel cell, Stirling engine, steam turbine, linear Fresnel solar field and double effect absorption chiller is introduced and investigated from energy, exergy and thermodynamic viewpoints. In this process, produced electrical power by the fuel cell and steam turbines is 6971.8 kW. Stirling engine uses fuel cell waste heat and produces 656 kW power. In addition, absorption chiller is driven by waste heat of the Stirling engine and generates 2118.8 kW of cooling load. Linear Fresnel solar field produces 961.7 kW of thermal power as a heat exchanger. The results indicate that, electrical, energy and exergy efficiencies and total exergy destruction of the proposed system are 49.7%, 67.5%, 55.6% and 12560 kW, respectively. Finally, sensitivity analysis to investigate effect of the different parameters such as flow rate of inputs, outlet pressure of the components and temperature changes of the solar system on the hybrid system performance is also done.     

小型太阳能溴化锂吸收式制冷系统的优化设计

小型太阳能溴化锂吸收式制冷机是当今制冷空调业中的研究重点,其中需要解决的关键问题是换热器的合理选择和优化设计,最终达到提高效率、减小体积和节约成本的多重目的。实验室设计的5 kW吸收式制冷机组为板式换热器和管壳式换热器的结合体,经过数值计算模拟,可达到理想效果。     

Building integration of concentrating systems for solar cooling applications

The high energy consumption in buildings in Mediterranean countries, especially in the spring and summer months due to the extensive use of air conditioning, requires immediate actions to minimise energy costs and environmental impact given the current energy crisis. Solar cooling systems offer an attractive solution, but the main drawbacks of this type of systems are the low efficiency of the currently used single-effect absorption chillers and the large areas of thermal collectors needed to produce the thermal energy. These large solar installations make difficult their building integration. A way to overcome these difficulties is the use of high efficient integrated solar concentrator systems able to achieve temperatures around 150 °C that could be used to activate the more energy efficient double-effect absorption chillers. In the frame of this concept, in the present work a comparison between two cooling systems for a specific three-floor building, with and without solar concentration, is performed. The first is a conventional system which consists of evacuated tube collectors feeding a single-effect absorption chiller. On the other hand, a Fresnel reflective solar concentrating system, integrated on the building façade, is coupled to a double-effect absorption chiller. The results show an important reduction of the solar collectors absorber area in the concentrating system compared with the standard solar thermal installation. However, the solar concentrating system requires a large aperture area. In addition, the rejected heat in the double-effect chiller is lower, implying that the investment and operation costs of the solar concentrating cooling system can be reduced significantly.     

大型建筑中应用应急柴油发机实现冷热电三联供及其实例分析

介绍了一种新型的高效节能中央空调冷暖系统－自备发电、余热利用及热泵冷暖系统。该系统充分发挥了大型建筑必备设备－自备电源应急柴油发电机的作用，使一次能源在使用中更加符合热力学的原理；该系统不追求某一种机组的高COP，而是利用各种设备的优点，有机匹配,以求一年中最高效的节能。通过与三种常规冷暖系统的一次能源利用率比较，得出该新型冷暖系统的一次能源利用率比三种常规冷暖系统的一次能源利用率高27．88％－104．6％以上。并通过实例计算了采用该系统的某大型广场的全年经济效益。     

Thermal performance of an ammonia-water refrigeration system

The conservation and efficient use of energy has led to alternate methods for air conditioning in buildings. Presently, two types of absorption air conditioning systems are widely used: the lithium-bromide-water system and the ammonia-water system. The first type is typically a water fired absorption chiller while the second one is a gas fired chiller. Some of the lithium-bromide-water systems use as a source of heat a stream of hot water supplied from solar collectors at a temperature level of the order of 95–100 °C. The purpose of this paper is to explore the possibilities to use solar energy to operate an ammonia-water system and to predict its thermodynamic performance.

The results indicate that it is feasible to use solar energy to operate an ammonia-water absorption-refrigeration system.