烟气冷却器在电厂烟气余热回收中的应用

为了解烟气冷却器对电厂烟气余热的节能作用,深入探讨了烟气冷却器的应用途径及其性能提升的影响因素,着重分析了烟气冷却器在电厂中的布置方式对节能效果的影响,通过比较烟气冷却器布置前后电厂各发电设备的效率及节能指标,达到电厂节能减排,烟气余热利用,提高系统经济性的目的。     

煤矿空压机节能及余热回收系统设计

为解决当前煤矿空压机电能消耗过大且效率较低的问题,结合实际生产开展了空压机节能设计和余热回收系统设计方面的研究。空压机节能方面,通过重新选型空压机及采用变频节能启动达到目的;余热回收系统方面,通过配置不同型号的余热回收系统实现对热能的回收利用。最后验证了空压机节能改造和余热回收系统的实际应用效果。实践证明,设计取得了理想效果。     

纺织厂空调改造与节能效果

<正> 我厂现有空调系统16个,其中老式空调10个,存在着送风阻力大、风量小、电耗高、效率低等问题,已经不适应节能和纺织生产工艺的要求。为了解决上述问题,我们对耗能高而又长期不能满足生产工艺要求的梳棉、细纱等5个空调系统进行了改造。一、改造方法和主要内容 1.由于我厂空调室的地方所限,无法做到完全按新型空调要求进行设计,只能根据本厂的具体情况,本着节省改造投资的原则,在保证主要设备与构件尺寸的前提下,尽量从简。     

低温热管能量回收装置在纺织厂中的应用

低温热管能量回收装置在纺织厂中的应用周耘低温热管能量回收装置可通过易气化工质的相变过程进行热量交换，是一种十分有效的热回收装置，在余热利用、太阳能利用等领域具有广阔的应用前景。本文以应用在潍坊２万吨粘胶短纤维的纺练车间空调通风为例，说明低温热管能量回...     

中央空调余热回收在宾馆酒店中的应用

介绍利用中央空调运行时产生的废热回收后生产出生活热水，对原有热水系统进冀改造，并对系统改造后的运行情况进行分析总结，从节能、环保、经济三方面说明了中央空调余热回收的可行性。     

余热回收与热管换热器

论述了节能在世界范围内的重要意义,指出对烟气余热进行回收利用具有很高的经济效益。分析了五种常用于烟气余热回收和的热换器的优缺点,着重阐述了热管换热器受到普遍欢迎的原因。     

浅谈几种典型空压机的余热回收

文章介绍了几种典型空压机的余热回收系统,如喷油螺杆空压机、无油螺杆空压机、离心式空压机等,对各种空压机的工作原理和相应的余热回收系统特点进行了阐述,这些丰富的空压机余热回收的途径和形式,可供有关单位和工程技术人员参考和采用,更好地进行余热回收,降低企业的能源费用,减少对环境的热污染,达到节能环保的目的。     

螺杆空压机余热回收及节能分析

基于螺杆空压机在工作过程中大量热能外排的情况,介绍了空压机余热回收系统的原理及实施方案,进行了节能量及经济效益分析。结果表明无论是从环保角度还是经济效益方面,空压机余热回收系统都具有一定的合理性及可行性。     

Energy analysis and waste heat recovery in a refinery

Petroleum refining is an energy-intensive industry and waste-heat recovery is essential. We investigate energy consumption of 4 refining processes: two crude distillation units, a vacuum distillation unit, and a platforming unit. Current heat-recovery practices and a new heat-recovery system are explored. Heat losses ranged from 25 to 62% of total heat input. The proposed heat-recovery methods increased the heat-utilization efficiencies by 12 to 48.5%, with overall heat losses reduced by 9.9 to 37.3%. A rotating regenerative heat exchanger is the heat-recovery unit of choice in terms of fuel saving and pay-back time.     

华栾制药厂余热综合利用方案分析

就华栾制药厂余热蒸汽的综合利用提出了设计改造方案,并对该方案进行了经济性及可行性分析与研究,从而为优化设计、比较方案提供经济技术方面的依据。计算结果表明:该设计方案是可行的,其设计改造方案比现有设备运行时具有明显节能效果和良好的经济效益。     

Second law analysis of a waste heat recovery steam generator

In recent years a great deal of attention is focussed on the efficient utilization of energy resources with minimum heat loss. There is a growing interest on second law analysis to minimize the entropy generation in various thermal units and thereby to improve and optimize the design and performance. In the present work, a waste heat recovery steam generator is considered, which consists of an economizer, an evaporator and a super heater. The unit produces superheated steam by absorbing heat from the hot flue gases. A general equation for the entropy generation has been proposed, which incorporates all the irreversibilities associated with the process. By using suitable non-dimensional operating parameters, an equation for entropy generation number is derived. The effect of various non-dimensional operating parameters, on the entropy generation number are investigated. The role of gas specific heat, non-dimensional inlet gas temperature difference ratio (τ), heat exchanger unit sizes (NTUB, NTUS, NTUE) on entropy generation number are also reported. The results will help to understand the influence of different non-dimensional operating parameters on entropy generation number, which in turn will be useful to optimize the performance of the unit.     

除氧器余汽余热回收装置的应用及节能效益分析

热电厂除氧器系统的排汽量较大,含有大量热能的蒸汽排至大气,浪费现象比较严重。为了达到节能创效的目的,采用新型余汽回收节能装置将其回收,可使热量得到充分利用,既实现节能降耗的目的,又达到了环保的要求。     

Thermodynamic analysis of waste heat recovery of molten blast furnace slag

Based on the first law of thermodynamics and second law of thermodynamics, using enthalpy–exergy compass, the thermodynamic analysis of the waste heat recovery system using different methods to recover the sensible heat of molten BF slag was studied. The results show that the heat efficiency of physical methods is 76.9%, and the exergy efficiency of recovery as steam is 34.2%; the heat efficiency of combined methods is 92.2%, and the exergy efficiency is above 60%. The heat efficiency and exergy efficiency of combined methods are higher than that of physical methods. On the promise of making comprehensive consideration for the exergy efficiency and the reaction condition, whether or not to consider the use of catalyst, the consumption of reactant and the amount of product, the C-CO₂/H₂O reaction are selected as the best reaction.     

Second-law performance of heat exchangers for waste heat recovery

Exergy change rate in an ideal gas flow or an incompressible flow can be divided into a thermal exergy change rate and a mechanical exergy loss rate. The mechanical exergy loss rates in the two flows were generalized using a pressure-drop factor. For heat exchangers using in waste heat recovery, the consumed mechanical exergy is usually more valuable than the recovered thermal exergy. A weighing factor was proposed to modify the pressure-drop factor. An exergy recovery index (η_II) was defined and it was expressed as a function of effectiveness (?), ratio of modified heat capacity rates (C^∗), hot stream-to-dead-state temperature ratio, cold stream-to-dead-state temperature ratio and modified overall pressure-drop factor. This η_II–? relation can be used to find the η_II value of a heat exchanger with any flow arrangement. The η_II−Ntu and η_II−Ntu_h relations of cross-flow heat exchanger with both fluids unmixed were established respectively. The former provides a minimum Ntu design principle and the latter provides a minimum Ntu_h design principle. A numerical example showed that, at a fixed heat capacity rate of the hot stream, the heat exchanger size yielded by the minimum Ntu_h principle is smaller than that yielded by the minimum Ntu principle.     

中小型砖厂轮窑余热回收净化系统设计

针对目前大多数中小型砖厂轮窑焙烧所产生的废气带有大量热量并不经处理直接排放的现象,提出应用砖厂轮窑废气余热回收净化系统将轮窑焙烧所产生的废气的余热通过换热装置进行回收,再利用回收的余热分别用来干燥湿坯砖以及加热生活用水,经过换热后的废气通入旋流板塔净化装置,经脱硫除尘后再将废气排出等处理措施。该系统不仅最大化地有效利用废气余热,废气进行脱硫除尘,而且降低了生产成本、减少了空气污染、实现了节能减排的效益。     

加热炉热管烟气余热回收系统的长周期运行

本文阐述了影响常压炉热管长周期高效率运行的主要因素 ,分析出热管腐蚀和积灰的成因 ,提出减缓热管腐蚀和积灰、延长其运行周期的措施