热泵干燥装置的技术经济及环境分析

热泵干燥具有节能、低温干燥及环境友好等优点,但与普通干燥装置相比,有初投资大等不足。本文以中小型热泵干燥装置为背景,对热泵干燥装置与普通干燥装置在采用电能、煤、天然气为能源时的技术、经济、环境特性进行了对比分析,为热泵干燥装置的应用提供了直接的参考。     

热泵干燥技术的发展及其应用的前景

1　引言热泵技术是世界上70年代末80年代初发展起来的一项高新技术。作为工业热泵技术在我国的发展也有十多年的历史了。而热泵干燥技术是以它独特的干燥原理及其高效能被人们所重视。特别是在家具、木材加工行业中的应用,优点十分显著,因此,我国早在80年代中期木材加工业就引进了德国、意大利、荷兰等热泵木材干燥装置。热泵干燥装置的市场占有比例在逐年提高,在木材干燥领域中已占到第二位。热泵技术在其它工业领域应用,随着国民经济的经济发展,也会越来越受到大家的欢迎。2　热泵干燥技术的特点热泵技术应用于干燥领域有着十分明显的优势…     

节能环保型热泵干燥装置

介绍一种具有回热循环的闭路式热泵干燥装置,其除效率高,能量利用率高,且封闭循环,是较理想的节能,环保型干燥装置。     

带回热循环的闭路式热泵干燥装置

介绍一种具有回热循环的闭路式热泵干燥装置,其除湿率高,能量利用率高,且封闭循环,是较理想的节能型环保型干燥装置。     

热泵干燥系统优化的理论分析

用当量温度法对热泵干燥的最佳工况进行了详细的分析计算,提出热泵干燥装置最佳蒸发温度概念,它对热泵干燥装置的节能运行具有指导意义,比较了不同制冷工质的干燥效果,研究了回热循环的节能原理。     

带回热循环的闭路式热泵干燥装置

介绍一种具有回热循环的闭路式热泵干燥装置,其除湿率高,能量利用率高,且封闭循环,是较理想的节能型环保型干燥装置。     

热泵干燥装置的节能研究

对热泵干燥装置混合工质进行优选,建立典型热泵干燥装置结构数学模型,研究提出目标函数并开发出适合热泵干燥结构的程序算法。     

相变贮热在热泵干燥机组中的应用研究

热泵干燥既能节约能量又可提高产品的质量,当干燥温度满足干燥要求后,热泵干燥机组往往通过排放掉一部分热量来维持干燥温度的稳定,这样降低了热泵干燥的能源利用效率,利用相变材料相变热效应,回收这部分能量,而且又在机组需要热量时将贮存的能量释放给干燥空气,实验结果证明了相变材料在热泵干燥机组中的应用具有明显的节能潜力。     

高温热泵在木材加工行业中的应用

分析了国内外木材加工行业中高温热泵的研究与应用现状,提出了采用高温热泵回收单板干燥尾气的方案,认为当前要重视高温热泵工质及相应热泵系统的研制,发展高温热泵与太阳能和常规蒸汽干燥的联合干燥技术,使高温热泵干燥装置标准化和规范化,保证机械的产品质量与稳定性,扩大高温热泵干燥机在我国的使用范围。     

余热回收式热泵干燥装置的设计与分析

为提高热泵干燥装置的节能效率,设计并研制了能够对干燥室排出的高温气体进行余热回收的热泵干燥装置,并对其进行了性能测试。采用可编程控制器对热风的温度、湿度和风速进行调节,并可对干燥室排出的废热进行回收利用。利用该热泵干燥装置对香菇进行的干燥实验表明:该热泵出风口温度可达65℃,干燥室内温度分布均匀;与电加热干燥装置相比,该装置的干燥时间可缩短5~7 h,每度电的处理量提高了2.3倍,并且提高了干燥品质。     

Metal hydride heat pumps

Heat pumps have been known for a long time, but, until the energy crisis of 1973, there were only a few studies covering them. Since that time, in addition to alternative energy sources, scientists and engineers have started studying heat pumps more earnestly. There are several kinds of heat pump and utilizations of them, but the most common one is the vapour-compression heat pump. In recent years researchers have started to study metal hydride heat pumps. The paper considers the metal hydride bed, its thermodynamics, and its utilization as a heat pump. It is also compared with conventional heat pumps. The results indicate that the metal hydride heat pump has several advantages, and its utilization in the industrial, commercial and residential fields is foreseen.     

Performance assessment of contact heat pump drying

A comparative analysis is presented of a novel plate‐type isothermal heat pump dryer and a conventional adiabatic heat pump dryer. The energy performance and drying capacity of each dryer type is investigated subject to operational constraints on the maximum acceptable relative humidity and temperature of air passing over the product. The analysis demonstrates that for applicable products, a significant opportunity exists for improving the energy efficiency of heat pump drying, by a factor of 2–3 times compared with current adiabatic heat pump dryers. The moisture extraction rate is also increased in the contact heat pump dryer, by a similar factor. However, these improvements are shown to be sensitive both to the impact of product thickness on heat transfer and to the relative humidity constraint. Copyright © 2010 John Wiley & Sons, Ltd.     

The contact factor for dryer performance and design

We describe an approach using the contact factor (CF) as the dryer performance and design parameter. The CF is calculated using known drying variables with a view to minimizing the drying costs. An algorithm to obtain the ‘economic’ CF for drying is presented. Besides being a design parameter of single‐stage dryers, the CF is a useful parameter in determining the schedule of cascade dryers in multi‐stage drying. We demonstrate the dryer component selection process using a set of design charts for heat pump dryers. Copyright © 1999 John Wiley & Sons, Ltd.     

热泵工艺在油田注水站的应用分析

热泵系统也称余热回收系统,是使用部分驱动能源(如燃气、蒸汽、燃气或热水),将余热形式为地热水、冷却水、洗涤水或伴油污水,温度在20~70℃的低品位能量取出,转移到45~100℃的中高温热媒中的系统。热泵系统在利用低品位热能的同时,仅消耗少量电能,节能效果显著。我国直到20世纪90年代,开始大面积应用热泵技术。目前,在热泵制造、安装和运行规模上,已走到了国际前例。现在,不管是压缩式热泵,还是吸收式热泵,也不论是设备还是系统,其技术已经成熟,热泵机组制热温度达到45~100℃,COP值(能量与热量之间的转换比率,简称能效比)也达到相当高的水平,机组的超小型化和超大型化技术得到长足发展,被广泛应用到建筑、烘干、石油化工、医药、筑路等领域。以热泵工艺在油田注水站的应用为分析对象,针对热泵的起源、发展、工作原理及在注水站的应用展开论述,着重从初期投资、运行费用、人工费用、社会效益、节约清水及10年费用现值方面,对注水站采用热泵冷却工艺与常规冷却工艺进行对比分析,提出了注水站采用热泵工艺有利于提高注水站系统的热能效率,降低运行成本,减少加热炉加热过程中产生的废气和余热排放,实现节能减排,对于热泵工艺在大庆油田注水站的应用具有借鉴意义。     

Performance study of a heat pump dryer system for specialty crops—Part 2: Model verification

The experimental and predicted performance data of a heat pump dryer system is reported. Chopped alfalfa was dried in a cabinet dryer in batches and also by emulating continuous bed drying using two heat pumps operating in parallel. Results showed that alfalfa was dried from an initial moisture content of 70% (wb) to a final moisture content of 10% (wb). The batch drying took about 4.5 h while continuous bed drying took 4 h to dry the same amount of material. The average air velocity inside the dryer was 0.36 m s^?1. Low temperatures (30–45°C) for safe drying of specialty crops were achieved experimentally. The heat pump drying system used in this study was about 50% more efficient in recovering the latent heat from the dryer exhaust compared to the conventional dryers. Specific moisture extraction rate (SMER) was maximum when relative humidity stayed above 40%. The dryer was shown to be capable of SMER of between 0.5 and 1.02 kg kW^?1 h^?1. It was concluded that continuous bed drying is potentially a better option than batch drying because high process air humidity ratios at the entrance of the evaporator and constant moisture extraction rate and specific moisture extraction rate values can be maintained. An uncertainty analysis confirmed the accuracy of the model. Copyright © 2002 John Wiley & Sons, Ltd.     

地热水源热泵技术应用市场前景

该文描述了利用水源热泵技术的直接、间接经济效益和环境效益；并针对水源热泵设备的类型及供暖规模适用范围进行了优化设计；通过动态监测的实际工程运行参数指出使用水源热泵比燃气锅炉更经济。     

污水源热泵技术及其应用

介绍了污水源热泵的特点。通过对空气源热泵、地源热泵和污水源热泵等不同采暖系统的经济性和环保效果分析显示，污水源热泵系统的初投资为地源热泵的70％左右。综合考虑初投资和运行费用等因素，污水源热泵系统的经济效果和环保效果最为显著。     

浅谈地源热泵空调系统的分类及其优越性

本文简述了地源热泵(GSHP)不同类型的划分,据此对目前常用的各种土壤源热泵、水源热泵作了进一步的分类,并从对自然资源的利用、对环境的影响、一次能源利用率、能效比等不同方面将地源热泵与传统空调系统作了对比性分析,显示了地源热泵系统的优越性,指出地源热泵将会成为21世纪最有效的供热和供冷空调技术之一     

A review of heat pump systems for heating and cooling of buildings in China in the last decade

Heat pump technology fully shows the principle of energy recycling in terms of Heating, Ventilating and Air Conditioning (HVAC). It avoids unipolarity of energy using in the conventional HVAC system. Heat pumps use high-grade energy as a driving energy, recovering and upgrading low-grade energy for avail, like a pump. Because heat source used in HVAC usually is low temperature heat, heat pump systems adopted in HVAC will help improve heating performance coefficient. Therefore, HVAC is one of ideal users of heat pump applications, and thus high-grade energy used in HVAC can be replaced with a large number of low-temperature renewable energy. Through the heat pump technology, natural low-grade energy stored in the soil, water, air or waste heat from variant industries and daily lives, is supplied for building cooling/heating and hot water serving. Therefore, vast applications and developments of heat pump technology are presented in HVAC in China, and some progresses are achieved in the system innovation, experimental research, product development and engineering application, etc. This paper reviews the progress of researches, applications and development in the field of heat pumps for building cooling/heating in China since the 21st century.