太阳能除湿溶液再生方式及装置的分析与研究

简介了太阳能除湿溶液再生的发展历史,归纳总结了除湿溶液的再生方式和再生装置,根据除湿溶液再生过程是否直接与外界接触,将太阳能除湿溶液再生装置划分为开式集热型再生器、闭式集热型再生器和封闭式再生器三种。两级式集热型再生器溶液的再生量大于单级式集热型再生器,且再生效率有所提高;溶液温度可调单元喷淋模块结构简单,便于制作,兼有除湿和再生的功能,同时还可以与热泵组合实现多级并用,提高了系统的效率。     

复合型太阳能溶液除湿空调的性能模拟

结合热湿地区的气候特点,设计了复合型太阳能溶液除湿空调系统,并通过数值模拟,分析了除湿器和再生器入口空气参数对系统性能的影响.结果表明,除湿器入口空气温、湿度从36℃和80%冷却减湿预处理到26℃和90%时,除湿器的体积可减小约63%,溶液循环量减小约58%;使用房间排风作为再生空气源,可明显提高溶液的再生效率和浓度,有效降低再生热源温度.     

溶液除湿过程热质交换规律分析

除湿器和再生器是溶液除湿系统的重要传热传质部件。建立了一个测试叉流除湿、再生模块性能的实验台,以溴化锂溶液为除湿剂,用除湿量、除湿效率和体积传质系数描述除湿效果,实验测试了溶液和被处理空气的进口参数对除湿器性能的影响。由实验数据得到的准则关联式,可供叉流除湿器设计参考使用。     

低温驱动双转轮除湿空调系统研究

本文针对常规转轮除湿空调系统再生能耗高和除湿温升大的缺点,提出了低温驱动双转轮除湿空调系统,并分析了该系统的热力过程。建立了转轮除湿空调系统的■分析模型,并在典型夏季工况下,计算了系统的■能耗,研究表明:相比常规转轮除湿空调系统,新型系统的再生温度降低了35℃,再生温度为65℃,较低的再生温度使新型系统更好地利用太阳能等可再生能源;新型系统的加热量和制冷量分别降低了49.6%和33.1%,加热耗■及冷却耗■分别减少了64.4%和37.5%,再生排风■损失降低了38.1%,总■损失减少了52.7%,■效率提高了114.7%。新型系统■分析研究表明:处理空气先预冷后除湿和降低再生空气含湿量的措施对降低转轮除湿空调系统的再生温度有利,两者与吸附热回收相结合的措施能大大降低系统的再生能耗、制冷能耗和总能耗,新型系统具有不可逆损失少以及热力完善度高的优点。     

CO2水源热泵驱动溶液除湿新风系统性能研究

提出了一套多功能CO2水源热泵驱动的溶液除湿新风系统,该系统以CO 2跨临界循环压缩机高温排气实现LiCl溶液再生,提高了热泵驱动溶液除湿系统的溶液再生效率,并以地下水为再冷源,减小了CO2跨临界循环节流损失.通过建立系统稳态数学模型,模拟分析了标准环境工况下,新风量、 除湿/再生内循环比、 溶液总流量、 再生空气流量...     

溶液除湿系统再生性能的研究进展

溶液除湿系统不存在温室效应,对环境友好,实现了热负荷和湿负荷的独立处理,提高了人们生活和工作环境的空气品质。但在溶液吸湿的过程中,溶液浓度会不断降低,溶液表面与空气之间的水蒸气分压力差会逐渐减小,溶液失去除湿能力,需要对溶液进行再生才能循环使用。再生器是盐溶液提浓循环使用的重要场所。本文简要介绍了溶液除湿系统再生性能的研究现状以及一些不同于传统再生的方法。     

利用冷凝热回收的除湿液再生装置研究

以某示范楼为研究对象,提出了一种节能的空调系统方案,该方案涉及一种新型除湿液再生装置,其技术特征是将冷凝热回收用于溶液再生.定义了温湿度独立控制溶液除湿空调系统总的冷源设备热力系数,并根据此系数判断空调系统是否节能.理论分析表明,利用高温冷水机组冷凝器产生的热量用于除湿液再生,其系统总的冷源设备热力系数可达到6.27,比传统空调系统的冷源设备热力系数提高了45.5%,节能潜力可观.     

溶液再生回流比例对溶液除湿系统性能的影响

给出了可调节再生回流比例的除湿系统流程,建立了系统各主要部件的数学模型。模拟得到了夏季工况不同除湿负荷、不同溶液再生回流比例下系统的能耗和性能系数(COP)。结果表明:降低溶液再生回流比例可提高除湿系统性能;在较低的溶液再生温度和较低的除湿负荷条件下,降低溶液再生回流比例对系统性能的改善作用较大;再生回流比例的降低受再生温度的限制,存在合理的较优再生回流比例。     

溶液除湿空调及热湿独立处理空调系统

综合比较各种除湿方式，得出溶液除湿是实现湿度独立处理的较为可行的方式。对溶液除湿空调的溶液除湿过程和再生过程进行了分析，提出采用分级和热回收的方法提高其效率，并通过模拟计算，得出其夏季工况下的能效比为1～3。介绍了基于溶液除湿的热湿独立处理空调系统的构成及其能源利用率高且可用低品位热源驱动等优点，比较了这种系统和传统冷凝除湿空调系统的运行经济性。     

被动除湿太阳房实验研究

从节能、环保、战略与效率的角度阐述了被动太阳房除湿与传统除湿方法相比，有其独特的优势。而且，高湿环境不仅影响到室内人员的热舒适感，而且对室内卫生条件，人体健康，室内设备，室内家具的使用寿命等也有不利影响。为了降低室内湿度，我们设计了一种新的除湿构件，利用太阳能使其再生循环使用，试验证明，这种除湿构件具有很好的除湿效果，可以在一定范围内推广使用。     

长沙地区太阳能溶液除湿独立新风系统能耗分析

基于长沙市太阳能资源分布情况,评价了太阳能溶液除湿在该地区的可行性,得到该地区太阳能保证率为89%。计算并比较了太阳能溶液除湿DOAS同常规空调系统的能耗情况:该系统比传统DOAS节电19.1%,比带全热交换器的一次回风系统节电32%,比一次回风系统节电52%。     

夏热冬暖地区太阳能溶液除湿空调的应用分析

本文介绍了太阳能溶液除湿空调系统的形式及其工作原理,并将该系统运用到广州某一小型办公楼上,利用DesT软件,进行了逐时模拟计算。计算结果表明：在不考虑传统空调的再热量,忽略其他传热损失下,溶液除湿空调系统用电量仅为传统空调系统的40％;由于通过溶液的蓄能来充分利用太阳能,使得燃气加热器的供热量仅为再生热负荷的13．4％;在广州地区的电、燃气价格下,太阳能溶液除湿空调系统的运行费用仅为传统空调系统的49．03％。     

溶液除湿空调系统蓄能性能分析

介绍了溶液除湿蒸发冷却空调系统的蓄能原理,分析了蓄能密度的影响因素。与冰蓄冷、水蓄冷和气体水合物蓄冷等常规蓄冷方式的比较结果表明,溶液除湿空调系统在蓄能方面有明显的优势,其蓄能密度远大于常规蓄冷方式。该系统可以利用太阳能作为再生能源,白天蓄存浓溶液用于夜间制冷,节能效果显著。     

溶液-湿空气热质交换过程的匹配研究

吸湿性溶液与空气的热质交换过程既有热量的交换又有质量的交换,提高该过程的可逆程度是提高溶液除湿空调系统性能的重要手段。在对溶液的性质进行合理简化的基础上,分析了溶液与空气的热质交换过程的流量比和过程需要吸收或释放的热量,得到在不同工况下,可逆过程所要求的流量比和应该补充或带走的热量。认为这一结论有助于溶液除湿空调流程的设计和相关参数的选取。     

TRNSYS simulation for solar-assisted liquid desiccant evaporative cooling

ABSTRACT

Recently, desiccant cooling systems are well thought of as a competent method for controlling the water content in the air. A solar flat-plate collector has been used as it decreases the dependency on non-renewable resources. Solar-aided liquid desiccant systems have been used to reduce the dependency of air-conditioning systems on non-renewable sources of energy. Manipal’s humid and searing climate provides certain benefits in setting up such a system. The suggested system has reliability and equipment life and also takes complete advantage of the available solar energy for the renewal of the liquid desiccant. TRNSYS simulation is used to predict the efficiency and feasibility of the system. The temperature and energy-load variations were successfully obtained. An effective simulation was developed whereby the solar air conditioning of a room was indicated.     

溶液全热回收装置与热泵系统结合的新风机组

提出了一种以溶液为媒介的全热回收装置和热泵系统相结合的新风处理机。安装于某医院的新风机性能测试结果表明：测试条件下，新风机夏季性能系数为6．3～7．3，冬季性能系数为4．7～5．0。新风机中吸湿溶液能去除空气中多种污染物，可避免新风和室内排风之间的交叉污染。     

Experimental study on dehumidifier and regenerator of liquid desiccant cooling air conditioning system

A new type of air conditioning system, the liquid desiccant evaporation cooling air conditioning system (LDCS) is introduced in this paper. Desiccant evaporation cooling technology is environmental friendly and can be used to condition the indoor environment of buildings. Unlike conventional air conditioning systems, the system can be driven by low-grade heat sources such as solar energy and industrial waste heat with temperatures between 60 and 80 °C. In this paper, a LDCS, as well as a packed tower for the regenerator and dehumidifier is described. The effects of heating source temperature, air temperature and humidity, desiccant solution temperature and desiccant solution concentration on the rates of dehumidification and regeneration are discussed. Based on the experimental results, mass transfer coefficients of the regeneration process were experimentally obtained. The results showed that the mean mass transfer coefficient of the packing regenerator was 4 g/(m² s). In the experiments of dehumidification, it was found that there was maximal tower efficiency with the suitable inlet humidity of the indoor air. The effective curves of heating temperature on the outlet parameters of the regenerator were obtained. The relationships of regeneration mass transfer coefficient as a function of heating temperature and desiccant concentration are introduced.     

溶液除湿空调系统在工业厂房应用的能耗分析

通过对深圳某工业厂房分别选用常规冷凝除湿空调系统和溶液除湿空调系统进行系统设计和理论计算分析,比较了两类空调系统的能耗及COP。在夏季室外设计工况下,常规冷凝除湿空调系统的COP为2.94,溶液除湿空调系统的COP为5.42。室外空气含湿量越小,对提高溶液除湿系统的性能越有利。溶液除湿空调系统在节能方面具有较大的优势。     

Performance analysis of liquid desiccant based air-conditioning system under variable fresh air ratios

In conventional air-conditioning system, fresh air volume is always restricted to save energy, which sacrifices indoor air quality (IAQ) to some extent. However, removing the latent load of air by liquid desiccant rather than by cooling is an alternative way of reducing energy consumption. Therefore, IAQ can be improved by increasing the volume of fresh air introduced into an air-conditioning system. In this paper, a liquid desiccant based air-conditioning system is studied, with the system performance under various fresh air ratios analyzed using simulation tests. In addition, the proposed system and a conventional system are compared. In the proposed system, with the increase in fresh air ratio, the heating load for solution regeneration rises, the dehumidification efficiency increases and the regeneration efficiency drops. The coefficient of performance (COP) of the liquid desiccant based system decreases sharply when the fresh air ratio exceeds 60%. The results also show that the proposed system can save power notably. The maximum power saving ratio is 58.9% when the fresh air ratio is 20%; however, the ratio drops when the fresh air ratio increases. These findings will be beneficial in the selection of fresh air ventilation strategies for liquid desiccant based air-conditioning systems.     

Evaporative air cooler coupled with variable frequency drive for dehumidification of indoor air

This study deals about the investigation of a solar-powered desiccant dehumidification system coupled with variable frequency drive (VFD). The proposed design of the system consists of two evaporative air coolers. One cooler performs as an absorber and the other one as desiccant regenerator coupled with a solar water heater. The VFD is connected with the first evaporative air cooler. In this work, using solar energy, a zeolite is regenerated as part of the investigation. Regeneration cycle for hot water absorption is explained and analysed. A simple expression for the cycle is proposed. System efficiency is derived with consideration of flow of work and heat to and from the system. The operating concentration of desiccant used greatly affected regeneration temperature limits and mass of strong solution for unit mass of vapour produced.