热泵精馏与常规精馏的热力学分析比较

以实际运行装置的丙烯精馏塔为例,采用PROII 9.4软件对丙烯—丙烷分离过程中常规精馏和热泵精馏分别进行模拟,通过分析模拟结果,对比两种精馏方式的公用工程消耗、能耗及其经济性。     

热泵精馏与多效精馏的分析和比较

化学工业中,精馏过程是能量消耗最大的单元操作之一,为了减少精馏能耗,通过改变传统工艺而引进了一些新工艺,热泵精馏和多效精馏便在其中且应用广泛。文章将介绍热泵精馏和多效精馏的理论,以及它们的在工业上的一些应用,对两者进行比较和分析。     

热泵精馏技术进展介绍

简要介绍了热泵精馏技术在国内外的发展情况,并对精馏技术的发展进行了讨论。     

乙烯开式热泵精馏系统的经济技术分析

介绍了茂名乙烯裂解装置开式热泵乙烯精馏流程和技术,分析了开式热泵乙烯精馏技术的能耗和投资,并与常规乙烯精馏技术进行了比较。     

两种乙烯热泵精馏的能耗对比

摘在相同基准条件下,用ASPEN PLUS软件计算乙烯闭式热泵精馏和开式热泵精馏的能耗,得出结论：在乙烯精馏塔仅一股进料的条件下,闭式热泵精馏能耗较低;在精馏塔有两股进料的条件下,两种精馏系统能耗相当。提出了乙烯热泵精馏流程的选取思路。     

醋酸丁酯热泵精馏新工艺

针对常规醋酸丁酯生产工艺能耗高的特点,提出将热泵精馏应用于醋酸丁酯生产,开发出醋酸丁酯热泵精馏新工艺。分析了新工艺流程的原理、特点,热泵的介质特性和操作参数,进行了能耗和经济性的比较。结果表明,与常规工艺相比,热泵精馏新工艺流程能降低能耗56.9%,是一种节能、经济、环保的新工艺。     

热泵技术在化工精馏中的应用

介绍了热泵的基本原理及其在精馏中的应用。正确配置热泵,是精馏塔降低能耗的一条有效途径     

热泵热集成精馏流程的优化设计与综合

从综合的角度详细讨论了热泵精馏的原理,提炼出了用于综合的热泵精馏规则,并开发了综合所用的热泵精馏简捷经济评价方法,提出了一个两水平综合策略,给出了热泵精馏综合步骤。实例研究表明,本文开发的算法及提出的规则用于热泵热集成精馏流程的综合,能够得出最优的絷泵精馏流程。     

水/乙二醇高温吸收式热泵循环的热力分析及实验研究

从热力学原理出发 ,理论分析与实验研究了水 /乙二醇高温吸收式热泵循环及各个单元设备的火用效率、火用损失、火用产生原因及其影响因素 ,实验结果与理论分析相吻合。     

热泵蒸煮过程的分析与计算

本文对可应用于蒸煮过程的压缩式热泵和蒸汽喷射式热泵,进行了分析与计算,结果表明在蒸煮过程中采用热泵系统。能收到极显著的节能、节水效益;还表明应以整个供热系统的供热系数和一次能源利用系数来衡量各热泵系统的能量利用性。     

ON THE EXERGY ANALYSIS OF BINARY DISTILLATION COLUMNS WITH HEAT INTEGRATION

The exergy analysis is done for the conventional distillation, the VR (Vapor Recompression) distillation, and the SRV (Secondary Reflux and Vaporization) distillation with the aid of computer simulation. It is shown that the careful use of thermodynamic diagrams helps us for the exergy analysis.     

基于化学热泵系统的叔丁醇脱水反应精馏过程

采用柱状阳离子交换树脂S-54作催化剂研究了叔丁醇脱水的反应精馏过程.在实验基础上建立了该过程的数学模型,采用超松弛法,并以动态方程逼近计算稳态过程对模型进行了求解,计算结果与实验结果吻合良好.在以上研究基础上考察了不同进料流量、进料组成、进料位置以及不同回流比等对反应转化率的影响,进行了上述工艺操作参数的模拟寻优,得到以下结论：反应精馏操作实现了水从反应体系中的有效移除,减小了水对反应的阻害作用,使叔丁醇接近完全分解;同时改变操作压力可以适用不同温度热源的热量回收要求.     

热泵吸附器中传热传质过程的研究

对吸附式热泵循环系统中的传热传质进行了理论分析和实验研究,建立了吸附器中热传导方程.计算求解值与实验结果相一致,说明了吸附器中的传热速率控制了热泵循环速度.据此,对吸附器中强化传热肋片进行了模拟分析,作为吸附器优化设计的理论依据.     

再生塔回流液泵故障原因分析及处理

分析合成氨装置三柱塞式冷凝液回收泵常见的故障,从备件质量及部件设计等方面找出其故障因素,针对故障因素确定相应的解决措施。通过改造确保了回流液泵的稳定运行,节约了维修成本。     

THE PERFORMANCE ANALYSIS OF A SOLAR ADSORPTION HEAT PUMP UTILIZING ZEOLITE COATINGS ON METAL SUPPORTS

The presence of temperature and concentration gradients inside a solar collector may decrease the efficiency of a solar adsorption heat pump. In this study, an arrangement involving zeolite synthesized on metal wire gauzes is proposed.in order to remove any possible limitations originating from the inefficient heat and mass transfer inside the solar collector. Accordingly, zeolite 4A is envisioned to be synthesized as continuous coatings on stainless steel wire gauzes which are assumed to be placed in the collector vertically in a manner assuring a firm contact between the absorber plate and the wire gauzes. A related mathematical model is presented which is solved by using the Euler-explicit, finite difference scheme and the effects of such an arrangement on the COP values, indicators of the efficiency of the solar adsorption heat pumps, are investigated. The mass of the zeolite and the inert materials, as well as the condenser and evaporator temperatures are taken into consideration. As a result, no possible drawback concerning the design of such an arrangement is anticipated and a zeolite layer thickness around 50-100μm; is determined to be sufficient to neglect the adverse effect of the mass of the metal wire gauzes on the efficiency of the solar adsorption heat pumps     

HEAT PUMP DRYERS: RESEARCH AND DEVELOPMENT NEEDS AND OPPORTUNITIES

ABSTRACT

As some previous research works on heat pump dryers (HPD) gave contradictory results, there is a need to review and identify R&D needs and opportunities in HPD. It was found that mathematical modeling cannot ignore the interdependence of the heat pump working fluid and the process air of the dryer. The performances of various HPD configurations with respect to all operating varibles need further investigation. A well defined mathematical model of combined dryer-drying material characteristic is required for the system modeling. The relative specific drying cost and relative useful energy were introduced as the dryer selection criteria. The role of the heat pump in the HPD system, CFC alternatives and non-conventional heat pump cycles using air or steam as working fluids deserve further investigation.