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1.
内加热式热泵干燥装置可提高干燥器出口空气的温度和相对湿度,增加空气从物料中吸纳水蒸气的能力。介绍了内加热式热泵干燥装置的结构和工作原理,建立了其SMER计算方程,并对干燥器进口空气温度、干燥器出口空气温度和相对湿度、除湿器出口空气温度对SMER的影响进行了计算和分析。  相似文献   

2.
概略介绍了PPC干燥系统工艺,从物料衡算、热量衡算的角度详细介绍了本系统内关键设备的选型,同时从设备组成、原理、材质等方面重点解析了本系统核心设备的结构特点,为相似物料特征的干燥系统设备选型提供了有益参考.  相似文献   

3.
水循环式热泵干燥装置是指热泵和干燥部分通过水循环耦合而成的热泵干燥装置,是一种较适宜于中小型热泵干燥装置的结构型式。以典型的物料干燥工艺为基础,对水循环式热泵干燥装置的冷却器、加热器、冷水循环部分、热水循环部分、热泵部件及工质的设计进行了分析和讨论,为水循环式热泵干燥装置的应用提供了较好的基础。  相似文献   

4.
热泵干燥节能技术研究与经济评价   总被引:1,自引:0,他引:1  
本文提供了一套热泵干燥实验装置及流程,并在整个干燥周期内对其动态性能进行了全面考察。对装置的适宜操作范围进行实验,运用正交实验法找到一组使得热泵干燥单位能耗最小的最优操作条件。以陶瓷粘土、木材、棉布为干燥物料,进行热泵干燥与电加热干燥节能对比实验表明,热泵干燥的节能效果为50~57%。本文还对热泵干燥、电加热干燥、蒸汽加热干燥的一次能源消耗和能源费用进行了比较和经济评价。  相似文献   

5.
容积换热系数是决定回转圆筒干燥器载热体向物料传热的主要因素。在设计任务给定后,确定了设计所需的基本参数。进行了物料衡算和热量衡算,解决了需要消耗多少干燥介质和热量的问题。依据物料衡算和热量衡算的结果计算并确定了设备的规格参数。本文从容积换热系数入手,结合油页岩干燥的工程实例,对直接加热转筒式干燥机参数(筒体直径、长度)进行了理论设计计算。  相似文献   

6.
针对现有己内酰胺装置环己酮肟化催化剂干燥工艺的不足,将干燥设备由耙式干燥机更换为桨叶干燥机,实现了浆液物料连续、清洁的干燥工艺过程。通过质量衡算和热量衡算,对干燥系统设备做了规格选型,分析了本工艺的技术优势和特点。经实际运行情况表明,该干燥器具有干燥效果好,能耗低等特点。该干燥系统具有安全可靠、易于操作及环境污染小的优点。  相似文献   

7.
本文研究了湿法制造热塑性片材工艺过程中的湿片干燥和压轧工艺方法。着重对干燥部分进行物料衡算和热量衡算,以确定干燥形式、炉体结构及其所需加热功率。  相似文献   

8.
为了克服湿微细粉易于结团形成“细粉群”、不易流化和干燥的缺点,在微细粉中加入惰性大颗粒物料,由于大颗粒的“搅动”作用,使细粉分散,可提高流化质量,从而提高微细粉的流化干燥热效率.在实验基础上进行了物料衡算和热量衡算,并进行连续干燥热效率的计算.该方法为微细粉的流化干燥提供一条新的途径.  相似文献   

9.
对影响聚丙烯粉料干燥效果的因素和设备结构进行分析,并对整个系统做热量衡算和物料衡算,分析了循环氮气的流量、流化床的干燥温度等因素影响粉料干燥的效果。  相似文献   

10.
热泵干燥装置中干燥介质的物性及其应用分析   总被引:1,自引:0,他引:1  
在热泵干燥装置中,干燥介质对干燥过程的传热传质速率、物料干燥质量和装置的能源效率均具有重要影响。给出了空气、氮气、二氧化碳、氩气、氢气、氦气六种干燥介质的热物性数据及其计算方程,并分析了其适宜的应用场合,为热泵干燥装置中选择适宜的干燥介质提供了较好的参考。  相似文献   

11.
Heat pump–assisted dryers are an alternative method for drying heat-sensitive food products at low temperature and less relative humidity with lower energy consumption. The mathematical models of a heat pump dryer consist of three submodels; namely, drying models, heat pump models, and performance models. Heat and mass balance of both refrigerant and air circuits in all components of the system are used for development of mathematical models. The models are used for design of different components of heat pump dryers operating under constant drying rate condition. A simple stepwise design procedure for batch-type, closed-loop heat pump dryer is also presented.  相似文献   

12.
水循环式热泵干燥装置是指热泵和干燥部分通过水循环耦合而成的热泵干燥系统,是一种中小型热泵干燥装置的结构型式。对水循环式热泵干燥装置的开机过程、调控特性、能源效率进行了分析,相关结论可为推广应用提供参考。  相似文献   

13.
Simulation of the heat pump cycle and the drying process has been carried out to obtain the design parameters of the dryer. The analysis indicates that a specific moisture extraction rate (SMER) greater than 3.4 kg/kWh can be obtained. A box-type heat pump dryer has been developed and investigated for the performance of drying of shredded radish. Heat pump drying took 1.0–1.5 times longer than hot air drying. However, the heat pump dryer showed considerable improvement in energy savings. The SMER of the heat pump dryer was about three times higher than that of the hot air dryer.  相似文献   

14.
农产品干燥加工占干燥行业能耗的12%左右,是一项高能耗的过程。为促进农产品加工业的健康发展,本文介绍了回热热泵、真空带式干燥、旋流床气流膨化、太阳能和热泵组合干燥等四种节能减排的新工艺新装备,同时还探讨了农产品干燥加工节能减排的发展方向。  相似文献   

15.
热泵干燥具有节能、低温干燥及环境友好等特点,控制热泵干燥装置运行在较佳的状态,是保证热泵干燥装置效率和可靠性的基础。以带循环空气旁通的封闭式热泵,干燥装置为例,对热泵干燥装置的调控方法进行了分析,给出了装置的被控参数和一组较佳的控制参数,并建立了各控制参数的计算公式。  相似文献   

16.
回热式热泵干燥高湿稻谷的试验研究   总被引:1,自引:0,他引:1  
应用带有嵌入回热器的热泵装置,对华南地区高湿稻谷进行干燥试验,测定其干燥速率、能耗和品质。并与同期作业的燃油低温循环稻谷干燥机进行对照。试验结果表明:回热式热泵干燥机的干燥速率较燃油低温循环干燥机提高20%,干燥周期缩短约12%,而干燥能耗及费用可节省30%以上,干燥品质两者无差异。  相似文献   

17.
Saffron is the most expensive spice and Iran is the largest producer of this crop in the world. Saffron quality is profoundly affected by the drying method. Recent research has shown that hybrid photovoltaic–thermal solar power systems are more efficient in comparison with individual photovoltaic and thermal systems. In addition, heat pump dryers are highly energy efficient. Furthermore, they are suitable for heat-sensitive crops such as saffron. Therefore, in the present study, the performance of a hybrid photovoltaic–thermal solar dryer equipped with a heat pump system was considered for saffron drying, in order to obtain a high-quality product and reduce fossil fuel consumption. The effect of air mass flow rate at three levels (0.008, 0.012, and 0.016 kg/s), drying air temperature at three levels (40, 50, and 60°C), and two different dryer modes (with and without the heat pump unit) on the operating parameters of the dryer was investigated. The results of the investigation showed that total drying time and energy consumption decreased as air flow rate and drying air temperature increased. Applying a heat pump with the dryer led to a reduction in the drying time and energy consumption and an increase in electrical efficiency of the solar collector. The average total energy consumption was reduced by 33% when the dryer was equipped with a heat pump. Maximum values for electrical and thermal efficiency of the solar collector were found to be 10.8 and 28%, respectively. A maximum dryer efficiency of 72% and maximum specific moisture extraction rate (SMER) of 1.16 were obtained at an air flow rate of 0.016 kg/s and air temperature of 60°C when using the heat pump.  相似文献   

18.
A total energy balance method for venting electric tumbler dryers was developed and the experimental methodology and calculation details are provided in this article. The energy to evaporate the water in the load; the energy to heat the water, textile, and dryer; energy losses by convection and radiation; and the energy not used in the process were considered to calculate the total output energy. This method was applied to a domestic venting electric tumble dryer. The results of the method suggested areas of improvement. The maximum difference between the measured total input and the calculated total output energies was 2.6%, indicating the accuracy of the method.  相似文献   

19.
One of the methods with the most potential to reduce energy consumption in grain drying is heat recovery from the dryer exhaust air. A parallel plate heat exchanger to recover heat energy from the exhaust air of a recirculating batch grain dryer was examined by theoretical assessments as well as by measurements in a scaled-down research dryer and experimental heat exchanger. In addition to the heat transfer performance, the operability in dusty conditions was investigated. Finally, the optimization of the heat exchanger was introduced by the aid of the calculation models and practical measurement. The heat exchanger performed satisfactorily, providing an average energy saving of approximately 18%. A significant improvement in the performance could be achieved by increasing the air velocity. No severe dust accumulation was observed, and a heat exchanger of this type could provide remarkable energy saving possibilities in grain drying. Further tests are necessary to ensure the operability in long-term use.  相似文献   

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