Waste heat powered reverse osmosis plants

The purchased power required for operation of reverse osmosis systems can be greatly reduced or sometimes eliminated by reclaiming waste heat from diesel engines, gas turbines, flare gases, etc. This can be accomplished by using a Biphase turbine to convert low level waste heat to shaft horsepower.The system can be designed to use waste heat from existing installations or to reduce the size of the generating equipment in new supplies.The Biphase conservation turbine is driven by a two phase stream generated by flashing a superheated liquid through a nozzle to the turbine. The turbine can be directly coupled to a pump shaft, to an electrical generator or to a combination of the two. Performance of the turbine is discussed. The waste heat recovery turbine and a hydraulic turbine to recover energy from the high pressure concentrated brine can be combined into one system.This paper describes the design of a seawater reverse osmosis system using waste heat from an existing diesel generating unit. The SeaRO system is designed to produce 750 cmd of 400 ppm water at an energy consumption of approximately 2.5 KWH of purchased power per cubic meter.A discussion of available desalination capacity at various quantities and temperature levels of the waste heat source is presented. A comparison of water costs obtained using this system and a conventional electrical drive is presented.     

INFLUENCE OF DESIGN AND OPERATING CONDITIONS ON THE SYSTEM PERFORMANCE OF A TWO-STAGE ADSORPTION CHILLER

This article aims at clarifying the possible design and operating conditions for silica gel-water adsorption refrigeration cycles driven by near-ambient temperature waste heat sources (between 45 and 75°C) with relatively small regenerating temperature lifts (15 to 45 K). A two-stage silica gel-water advanced adsorption chiller is introduced and a simulation model of the chiller was developed to analyze the influence of operating and design conditions on the system performance (coefficient of performance, COP, and cooling capacity). It was hypothesized that the proposed chiller can be driven by low temperature waste heat at 55°C to produce effective cooling. Simulation results show that the operating conditions such as cycle time and hot and cooling water inlet temperature have an influential effect on cooling capacity and COP. COP is proportional to cycle time and heat transfer coefficient as well as inversely proportional to the cooling water inlet temperature, while there are optimum values of hot water temperature and silica gel weight for maximum COP. Cooling capacity mainly improves with the addition of silica gel weight and decreases as cooling water temperature increases. Simulation results also revealed that the system performance can be improved significantly by setting the design and operating conditions optimally.     

INFLUENCE OF DESIGN AND OPERATING CONDITIONS ON THE SYSTEM PERFORMANCE OF A TWO-STAGE ADSORPTION CHILLER

This article aims at clarifying the possible design and operating conditions for silica gel-water adsorption refrigeration cycles driven by near-ambient temperature waste heat sources (between 45 and 75°C) with relatively small regenerating temperature lifts (15 to 45 K). A two-stage silica gel-water advanced adsorption chiller is introduced and a simulation model of the chiller was developed to analyze the influence of operating and design conditions on the system performance (coefficient of performance, COP, and cooling capacity). It was hypothesized that the proposed chiller can be driven by low temperature waste heat at 55°C to produce effective cooling. Simulation results show that the operating conditions such as cycle time and hot and cooling water inlet temperature have an influential effect on cooling capacity and COP. COP is proportional to cycle time and heat transfer coefficient as well as inversely proportional to the cooling water inlet temperature, while there are optimum values of hot water temperature and silica gel weight for maximum COP. Cooling capacity mainly improves with the addition of silica gel weight and decreases as cooling water temperature increases. Simulation results also revealed that the system performance can be improved significantly by setting the design and operating conditions optimally.     

不同余热情况下有机朗肯循环和卡琳娜循环能量性能对比

有机朗肯循环和卡琳娜循环都是发展前景广阔的低温余热动力利用技术,这两种技术在余热利用方面各有其优势和劣势。在炼厂中,余热资源分布广泛,针对不同余热热源选择合适的动力循环系统对能量的有效利用具有实际意义。热效率和(火用)效率是评价动力循环系统的两个重要指标。通过将余热资源分成3类,即显热热源、复合热源和潜热热源,用Aspen Hysys软件对有机朗肯循环和卡琳娜循环进行流程模拟,考察了余热资源特性对有机朗肯循环和卡琳娜循环能量性能的影响。结果表明当余热为显热热源时,卡琳娜循环系统优于有机朗肯循环;当余热为复合热源且潜热与显热比R=1或当余热为潜热热源时,有机朗肯循环优于卡琳娜循环。     

硫铁矿制酸干吸工段废热回收系统

介绍一种可用于硫铁矿制酸干吸岗位废热回收系统。该系统基于高温吸收工艺,采用两台阳极保护酸冷器串联的方式对出循环酸进行冷却,同时部分回收低温位废热,用于预热锅炉用水。该系统能有效回收利用低温位废热,具有经济效益明显,投资省,安全风险低等特点,可在硫铁矿制酸企业推广应用。     

Energieeinsparmöglichkeiten mit Dampf- oder Heißwassererzeugern

Possibilities of Energy Saving with Vapour or Hot Water Producers Shortage of energy is a fact and becomes a problem of world wide interest. A steam or hot water producer should be able to produce valuable steam at low costs. The Clayton steam hot water producers for example have all desirable properties of efficiency to lower the heating costs. The efficiency at low evaporation becomes even higher. The energy costs can be lowered up to 12% by a short heating time. 5-15% of the fuel costs can be saved by use of heat exchangers in systems in which the occurring hot condensate can be exploited. This can be carried out very easily by the Clayton-system. Thus result the following advantages: good efficiency, counter-current principle, compact construction, quick heating, closed condensate system. Waste heat boilers of the same construction exploit the waste heat which would be lost otherwise.     

A novel hybrid adsorption heat pump water heater

A hybrid adsorption heat pump water heater has been studied for domestic use. It is a water heater with dual heat sources, and it combines the performances of adsorption heat pumps and conventional gas boilers. Moreover, functional adsorbent material‐zeolite (FAM‐Z02, Mitsubishi Chemicals) and water are a new adsorption pair for adsorption heat pumps. This article describes the operation, design, and performance analysis of one such water‐heating device. The experimental results showed that the hybrid water heater in the whole year has a stable COP even at low ambient temperature. The hybrid water heater can thus achieve high energy efficiency.     

Optimal water purification using low grade waste heat in an absorption heat transformer

A proposal for rational energy saving using wasted heat is showed in the present paper. Thermodynamicmathematical model is presented like an effort for water purification from waste heat. This paper describes computing results of heat transformer operation for water purification using low grade waste heat. Equations, parameters and simplifications used in the model are briefly described. The main parameter of the carried out study is the coefficient of performance (COP) defined for reversed heat pumps and the second main parameter is absorber temperature, both parameters has been showed and correlated between them. Main objective of this work is to show the optimal operating condition for different process which deliver low grade waste heat and requires water purification. Assisted computing simulation was used for obtain these results. The main conclusion is an ecological proposal for optimal recover of low grade waste heat. Many operating conditions are showed in graphical form and discussed for different environment conditions.     

船用蒸馏造水机设计分析

造水机是重要的船舶辅机之一,使用蒸汽或内燃机缸套冷却液余热作为驱动热源,为船舶提供淡水.目前国际市场上船用蒸馏造水机已由管壳式换热器向板片式换热器过渡,国内相关设计产品和技术研究比较缺乏.本文为了研究板式蒸馏造水机换热及流动特性,以内燃机冷却液余热作为驱动力,选取实际运行工况,从热力学和流体力学角度分析研究板式蒸馏造水装置的设计要点,通过对造水机的板式蒸馏器进行热力计算和换热计算,对引射器进行结构改进设计以及对造水机的整体工艺流程设计,得到船用板式蒸馏造水机各部分的结构和详细尺寸参数.计算得到额定工况下的理论产水量并进行低负荷实验.结果表明,造水机产水品质和运行特性符合设计要求,为板式造水机制造和研发提供参考.     

新型空气-水双热源复合热泵系统性能和除霜实验

针对低温环境条件下热泵逆循环除霜存在的诸多问题,提出了一套具备预热除霜功能的新型空气-水双热源复合热泵系统（new air-water double source composite heat pump system,AWDSHPS-N）,通过阀门切换和低温水源侧水泵的启停控制可直接进入除霜模式,除霜过程中可保证制热的连续性,每次除霜时长不超过5 min。利用恒温恒湿环境仓模拟室外环境条件,可调控水温的低温水箱模拟太阳能等低温热源搭建AWDSHPS-N实验台,对不同测试工况下,单空气源制热模式（air source heating mode,ASHM）、单水源制热模式（water source heating mode,WSHM）、空气-水双热源制热模式（air-water source heating mode,AWSHM）3种制热模式将水从18℃加热至51℃的系统性能系数（coefficient of performance,COP）进行了实验,结果表明：AWSHM的COP比ASHM提高了6.1%~20.5%;当环境温度和低温水源温度均高于15℃时,系统COP高低顺序为AWSHM、ASHM和WSHM。     

基于机械蒸汽压缩蒸发的油田污水脱盐系统及分析

针对油田污水污染物成分复杂、污染性强不适合膜法脱盐的特点,提出用机械蒸汽压缩蒸发（MVC）技术对油田污水进行脱盐处理的技术方案。建立了基于MVC的油田污水脱盐系统的工艺流程设计计算模型,系统分析了降膜蒸发器传热温差、油田污水温度和蒸发温度的影响。结果表明：传热温差是影响系统装置规模和运行电耗的控制因素,减小传热温差可以明显降低压缩机比电耗,付出的代价是系统比传热面积的增大;MVC系统的热力完善度高,无废热排放,油田污水温度越高,系统比传热面积减小;在其他条件允许的条件下,提高系统的运行温度有利于改善系统的性能。     

水管-热管复合式废热锅炉在硫酸生产中的应用

在介绍水管-热管复合式废热锅炉的结构及性能的基础上,列出了水管-热管复合式废热锅炉的基础设计参数,并对其水管换热面和热管换热面的管壁温度进行了简单衡算,结果表明,通过合理的换热面设计可以避免低压废热锅炉烟气露点腐蚀并减少灰堵.     

Usability of low temperature waste heat for sea water desalination

Waste heat - energy that is cooled away from a process - appears at two very different temperature levels. The waste heat that is 50° C warmer than the ambience, can be utilized by a multi-effect-distillation process, and it is competitive to utilize it at least as thoroughly as the first-rate energy.At low temperatures, less than 20 °C above the ambient temperature, waste heat can be technically, and economically utilized, if the temperature difference is 7... 15 °C, depending on the pumping energy cost.     

Development of water re-use treatment system for municipal wastewater

The move for environmental protection and preservation of clean water sources has given rise to the latest tendency in Japan toward reuse of waste water after advanced treatment. As a means of saving water and securing water sources, water reuse systems are beginning to be installed to treat waste water for reuse as flushing water and cooling water for air conditioners.This study was conducted with the aim of developing a compact high-performance water treatment system that may meet the stated requirement.Most water reuse systems in practical use today are based on biological treatment. With this process, treatment is slow and equipment takes up much space. In addition, it involves a large amount of sludge.In an attempt to overcome these disadvantages, we developed a physico- chemical treatment technique that combines the three elementary techniques of dissolved air flotation, foaming separation, and activated carbon packed electrolyzer, and that permits multifunctional treatment with compact equipment. The activated carbon packed electrolyzer, which forms the core of the new system, is a newly developed technique. The purification mechanism was established, and conditions of application to actual waste water were determined. The electrolyzer was combined with the dissolved air flotation and foaming separation methods, to make up an optimum system.With a 10 m³/d trially manufactured apparatus, a demonstration test on reuse of sewage was performed to study the performance and economics of the system. The desired target was achieved and prospects were gained for commercialization.     

有机朗肯循环热电联供系统的实验研究

有机朗肯循环低温热力循环性能优越,易于小型化和自动运行,非常适合于分布式热电联供系统。依托已有的ORC-CHP实验平台,对热源温度101℃,膨胀机乏汽余热利用温度21.6～48.7℃时系统的热力性能进行了实验研究。在该温度范围内,ORC-CHP系统的综合能量效率96%～97%,其中热功转换效率4.4%～5.1%,乏汽余热利用效率91%～92%;从可用能角度出发,系统综合可用能效率50.0%～75.3%,其中热功可用能效率24.4%～19.2%,乏汽余热可用能效率25.7%～56.2%。实验表明该系统可以高效利用膨胀机乏汽余热,明显提高了有机朗肯循环的综合利用效率。     

采用自然工质水的高温热泵系统性能分析

面对严重的能源与环境问题,开发节能与环保的新技术一直都是国内外特别重视的研究热点。采用自然工质水的高温热泵系统结合了高温热泵与自然工质水的优势,不仅可以有效地回收低品位热能,而且绿色环保,是理想的下一代高温热泵技术。从理论计算以及实验验证两方面对采用自然工质水的高温热泵系统进行了性能分析研究。结果表明,负压条件下蒸发、正压条件下冷凝的水蒸气闭式热泵循环系统是可行的,同时实验结果表明当压缩机吸气温度为80℃,排气饱和温度从117℃提高到133℃,系统压比从3.47升高到5.94时,采用自然工质水的高温热泵系统COP从5.6下降到3.7。其中压缩机的排气饱和温度为120℃,压比为4.2时,热泵系统的COP接近于5,性能优越,在工业生产中具有较大的推广应用价值。     

焦炉烟道气余热负压蒸氨成套装置技术

分析了传统蒸汽蒸氨技术的不足,介绍了近年来导热油蒸氨、管式炉蒸氨、负压蒸氨技术的进展情况,研究开发了焦炉烟道气余热负压蒸氨成套装置技术,将热管技术、焦炉烟气-剩余氨水换热器技术成功应用于80万t/a焦炭生产系统,焦化废水处理成本降低40%,蒸氨废水量减少25%,提高了处理水水质,为焦化废水实现资源化利用和零排放创造了有利条件。     

水管-热管复合式废热锅炉在硫酸生产中的应用

介绍了水管-热管复合式废热锅炉的结构和性能优势。水管-热管复合式废热锅炉在550～850℃高温区间采用水管换热面,在330～550℃低温区间采用热管换热面,在中、低压运行状况下,通过优化设计可保证水管换热面和热管换热面的管壁温度均高于烟气露点。目前水管-热管复合式废热锅炉已在秦皇岛双益磷化有限公司和青岛东方化工有限公司...     

Energy analysis of a lignite predrying power generation system with an efficient waste heat recovery system

Lignite has been extensively used for electricity generation in many regions worldwide. However, its high water content has obviously negative effect on plant thermal efficiency. Performance of lignite-fired power plant can be improved by predrying the lignite before combustion. In addition, recovery of waste heat from the dryer and the power generation system will enhance the plant thermal efficiency further. In the present study, a new lignite predrying power generation system integrated with an efficient waste heat recovery system was proposed. Both dryer exhaust waste heat and steam turbine exhaust latent heat were recovered to heat boiler feed water. Energy analysis indicates that system performance is improved significantly. The plant thermal efficiency increases linearly with drying degree and then increases at a lower rate. The generation of unused dryer exhaust changes the variation tendency of system performance with drying degree.     

集散控制系统（DCS）在多热源热水工程系统中的应用

在分析多热源热水工程控制特点的基础上,针对目前热源供水自控系统存在的问题,给出了DCS系统的控制结构及其相关软、硬件的设计方案.实际数据监测结果表明,DCS控制系统弥补了现有系统控制方面的不足,改善了网络通信的稳定性,降低系统运行成本.