海水淡化技术进展及能源综合利用

海水淡化技术是将海水中的盐和水分离的技术。介绍国内外海水淡化技术发展历程,指明未来海水淡化技术发展方向,并结合我国能源现状建议采用水电联产低温多效蒸发海水淡化系统。该系统利用电厂的低品热源作为海水淡化过程的热源,实现能源的综合利用,降低制水成本,是适应我国国情、解决沿海地区淡水资源短缺的有效途径。     

低温多效蒸馏海水淡化水热电三联产系统经济性分析

对于凝汽式机组,提出采用低真空运行后的高温排汽作为低温多效蒸馏海水淡化的热源,实现水电联产.在此基础上,冬季利用一部分汽轮机排汽用于对热用户供暖.电厂在低真空运行模式下的热力计算采用矩阵法并基于弗留格尔公式进行变工况计算.低温多效蒸馏海水淡化系统的数学模型采用等温差法建立,并同时建立了制水成本的经济性计算模型.根据计算结果分析了低温多效蒸馏海水淡化系统的蒸发器效数、供热负荷、蒸发器传热系数和制水成本之间的关系,并得出了影响制水成本的主要因素及其敏感性分析.     

热电联产低温多效蒸馏海水淡化系统的节能分析

本文对比分析了热电联产海水淡化系统造水比Ｐｔ和单位当量电耗率ＥＥＣＲ,研究了分析了热电联产低温多效蒸馏（ＬＴ－ＭＥＤ）海水淡化系统利用蒸汽喷射器的节能效果。     

基于新型高导热系数材料设计的高效换热器

以新型高导热系数材料为基础,借助计算机辅助设计和流体模拟软件,设计了一种新型高效的换热器。换热器可以大规模的应用于低温多效海水淡化系统中,通过提高低温多效海水淡化系统原海水的温度,可以降低制水的抽汽量,同时降低发电循环水的温度,提高汽轮发电机组的循环热效率。通过计算机对换热器内部流场的模拟,表明换热器内部流体的流动均匀、压损较小,不易堵塞,可以大规模的应用于生产,同时为换热器的设计提供了一种新的方法。     

低温多效海水淡化工程材料的选用

通过对众和海水淡化工程有限公司参与设计并制造的三台低温多效海水淡化设备的研究,介绍了低温多效海水淡化工程用材料的选取,探讨了常用在低温多效海水淡化工程上的一些材料及其性能。在此基础上提出了对低温多效海水淡化工程材料选取的一些建议。     

横管降膜低温多效蒸发海水淡化系统的优化设计

随着横管降膜蒸发技术在低温多效蒸发海水淡化系统中的应用和推广,低温多效蒸发海水淡化技术以其传热系数高、热耗量小、要求供热的温位低等优点成为未来第二代海水淡化技术的主流技术.本文开展了横管降膜低温多效蒸发海水淡化系统的优化设计,比较了不同流程下低温多效蒸发海水淡化系统的热力特性,串并结合流程以其传热面积小、设备制造成本低...     

低温多效太阳能海水淡化装置最优集热系统的匹配研究

利用实际天气的太阳辐射值,根据一套低温四效太阳能海水淡化系统稳态实验数据,通过模拟计算,研究分析与该海水淡化系统匹配的太阳能集热系统参数,给出太阳能集热系统集热器面积和储热水箱容量、海水淡化系统启动和暂停温度等参数的最佳取值范围,计算了该装置的年淡水产量,为太阳能海水淡化装置的设计提供一种有效地方法.     

大型水平管降膜蒸发器管外热力参数分布计算分析

将分布参数方法与三维有限容积数值计算方法相结合,对大型水平管降膜蒸发海水淡化装置内的海水蒸发过程进行了模拟计算,获得了海水温度、海水盐度、二次蒸汽流速等参数的三维空间分布。详述了传热系数、海水沸点升高、传热温差等参数的空间分布特征。为低温多效蒸发海水淡化装置的工作特征理论提供了支持,为海水淡化装置的大型水平管降膜蒸发器分析与设计提供了理论基础。     

低温多效海水淡化造水比影响因素研究

低温多效海水淡化技术以其诸多优势得到市场广泛应用。为进一步提升电厂余热等低品位热源利用效率,减少海水淡化过程中的热力消耗,针对冬夏季不同海水温度引入条件、进料海水温度及流量控制参数、蒸发器效间温差等因素对低温多效海水淡化的造水比进行分析。研究结果显示,优化设计和分配进料海水的热力参数对提升造水比有直接重要的影响。     

热泵循环海水淡化系统

对现有的热法海水淡化方法进行了节能评述,并提出一种综合了低温多效蒸馏与压汽蒸馏两种海水淡化方法技术优势的新系统,通过对此系统的设计计算,得出结论：本文提出的利用热泵循环的节能海水淡化系统能耗低,在热法海水淡化系统中最为节能。     

Modeling and optimization of a solar driven membrane distillation desalination system

The desalination technology using membrane distillation driven by solar energy is a feasible solution for reducing the energy cost. A dynamic simulation model for a solar driven membrane distillation desalination system (SMDDS) is developed on the Aspen Custom Modeler^® (ACM) platform for the system performance and optimization study. The rigorous model for the spiral-wound air gap membrane distillation (SP-AGMD) module takes into account the heat and mass transfer resistances associated with each composing layer. The effects of adopting different objective functions, solar radiation conditions, thermal storage tank configurations, as well as the flowrates of the membrane distillation module and the thermal storage tank on the optimized performance are reported. Simple thermal storage tank and lower flowrate of the membrane distillation module are advantageous to higher water production rate. A control system using conventional PI (Proportional/Integral) controllers is proposed and the water production rate can reach about 87% of the optimal result for clear sky operation.     

Experimental validation of the distillation module of a desalination station using the SMCEC principle

This paper presents the simulation and the experimental validation of the distillation module of a desalination unit, currently operating in Sfax, Tunisia. The desalination process is based on the Solar Multiple Condensation Evaporation Cycle (SMCEC) principle.The work presented in this paper focuses on modelling the desalination module as it is supplied with either water heated by solar energy or geothermal water. Geothermal water resources are abundant in Tunisia with salinity levels of 1–50 g/l. The simulation of the dynamic behaviour of the desalination module with and without disturbances on the inlet temperature was carried out to predict the variations of key output variables subjected to thermal variations. Such variables include water temperature, air temperature, humidity in the evaporation and condensation chambers and the amount of produced distilled water. To validate the dynamic model of the distillation module, a series of experiments was conducted. Experimental results were compared with the simulation results. It was shown that the developed model is able to predict accurately the trends of the heat and mass characteristics of the evaporation and condensation chambers. As a result, the proposed model can be used to design and test the behaviour of such a type of desalination unit.     

Design and modeling of a multigeneration system driven by waste heat of a marine diesel engine

In this study, a novel marine diesel engine waste heat recovery layout is designed and thermodynamically analyzed for hydrogen production, electricity generation, water desalination, space heating, and cooling purposes. The integrated system proposed in this study utilizes waste heat from a marine diesel engine to charge an organic Rankine and an absorption refrigeration cycle. The condenser of the Organic Rankine Cycle (ORC) provides the heat for the single stage flash distillation unit (FDU) process, which uses seawater as the feedwater. A portion of the produced freshwater is used to supply the Polymer Electrolyte Membrane (PEM) electrolyzer array. This study aims to store the excess desalinated water in ballast tanks after an Ultraviolet (UV) treatment. Therefore it is expected to preclude the damage of ballast water discharge on marine fauna. The integrated system's thermodynamic analysis is performed using the Engineering Equation Solver software package. All system components are subjected to performance assessments based on their energy and exergy efficiencies. Additionally, the capacities for power generation, freshwater production, hydrogen production, and cooling are determined. A parametric study is conducted to evaluate the impacts of operating conditions on the overall system. The system's overall energy and exergy efficiencies are calculated as 25% and 13%, respectively, where the hydrogen production, power generation, and freshwater production capacities are 306.8 kg/day, 659 kW, and 0.536 kg/s, respectively. Coefficient of Performance (COP) of the absorption refrigeration cycle is calculated as 0.41.     

供热机组-海水淡化联产系统的经济性分析

针对供热机组-海水淡化联产系统的特点,应用循环函数法、等效焓降法和汽轮机变工况分析理论,建立了计算分析矩阵模型,得出了用于海水淡化的抽汽对供热机组发电和供热两方面以及制水成本影响的计算分析方法.研究结果表明,增加夏季供热负荷用于海水淡化,能够增加供热机组的发电热效率和热能利用率,同时降低海水淡化的成本;采用制水电耗率（ELWP）比采用传统的造水比（GOR）指标更能够准确地评价海水淡化系统热性能;该水电联产系统能够提高热电机组的能源利用效率,有效解决沿海地区火电厂的缺水问题.图3表1参7     

Characterization of Pool Boiling of Seawater and Regulation of Crystallization Fouling by Physical Aberration

ABSTRACT

As fresh water becomes increasingly scarce desalination has become an important technique to meet the portable water requirements around the world. Thermal distillation continues to be one of the most important and widely used methods of desalination currently used. Scale formation, corrosion of the heater surface, and the subsequent degradation of the heat exchanger is one of the biggest challenges in thermal desalination. In this paper, pool boiling of seawater is characterized using standard artificial sea water. Various boiling characteristics such as critical heat flux and heat transfer coefficient are analyzed. The nature of the scales formed on the heater surface and their effect on the heat transfer efficiency are studied. A passive method to reduce the thermal resistance due to scale buildup from crystallization fouling using stainless steel beads is examined.     

LiBr吸收式空调与海水淡化联合运行装置工艺流程的研究

将LiBr吸收式空调排放出的废热应用于多效蒸馏法 (MED)海水淡化工艺流程是海水淡化领域一个全新的设计概念。本文对这种联合运行的热力循环进行了描述和论证 ,并用一算例证明此工艺流程在技术上是可行的。该装置利用LiBr冷水机组排出的废热加热预处理后的海水。本文给出算例中的理论计算值可供设计做参考     

应用人工神经网络(ANN)分析热泵型海水淡化系统产水特性

利用人工神经网络来模拟仿真热泵型海水淡化系统的性能。以空气入口干球温度和湿球温度、预冷器进口冷却水温度、预冷器出口冷却水温度、海水喷淋温度作为输入参数,建立了海水淡化系统产水(淡水)模型。对建好的神经网络模型经训练学习后,用来模拟预测预冷器和蒸发器的产水值,并且与数值模拟产水值、实验产水值进行了比较,误差较小。表明利用人工神经网络(ANN)建立的热泵型海水淡化系统仿真模型取得了满意的结果。     

压汽闪蒸海水淡化方法的研究与进展

分析、比较、归纳出现有海水淡化方法中,多级闪蒸法和多效蒸馏法在开路热焓过程中,有二次蒸汽的凝结潜热损失问题、蒸馏法的结垢与腐蚀问题、反渗透法的海水前处理与产品水质不稳定问题.进而综合其优点,首次提出:由热功效率最高的压汽法,来驱动产品水质最好的闪蒸法,这样一种全新、最优、集成的压汽闪蒸法海水淡化工艺,兼具投资成本最低、独立闪蒸操作、模块化组合生产等技术优势.由于集成技术成熟而全面,装置运行安全而可靠,必将以卓越的技术性、经济性,逐步取代现有各种方法,统一海水淡化市场,引导海水淡化技术发展.     

天津石化炼油节能优化措施及潜力分析

天津石化1000×104t/a炼油工程由3号常减压、2号加氢裂化、重整抽提、2号延迟焦化、2号柴油加氢、蜡油加氢、航煤加氢、2号硫磺回收等装置及储运系统和公用工程系统组成。炼油新区在设计中进行了能量综合优化,采取了一系列节能措施。在流程设置上,加氢装置采用热高压分离器流程和循环氢脱硫流程,一些装置采用热直供料,2号柴油加氢装置与航煤加氢装置实现了热联合。在低温热利用方面,设立高温热媒水系统,回收新区加氢装置低温热,用来加热热电部除盐水。设立低温热媒水系统,回收2号延迟焦化装置的低温热,冬季为新区装置采暖伴热提供热源,夏季为溴化锂机组供热。炼油新区各装置实施了节能优化,主要项目有:重整抽提装置蒸汽凝结水热能利用,2号延迟焦化和重整抽提装置部分蒸汽伴热改为水伴热,2号延迟焦化装置热出料流程优化。针对炼油新区在低压蒸汽平衡、中压蒸汽管网运行方面存在的问题,提出优化措施。