空分装置预冷系统冷冻水改造

由于夏季循环水系统水温高,以及溴化锂冷水机组制冷效果差,空冷塔出口温度超标,影响空分装置的稳定运行。利用低温、洁净的低压生产消防水替代进入空冷塔上部的冷冻水,降低了分子筛吸附器入口温度,保证了系统的稳定运行,同时降低了运行成本和检维修费用。     

高压静电水处理设备在制冷循环水系统的应用

介绍了高压静电水处理器的基本结构、原理。将其应用在氯碱制冷系统循环水装置，进出氨冷凝器冷却水温差从～4 ℃提高到～7 ℃，整个夏季节约用水100 kt，避免人工清洗管板，每年可节约费用19.4 万元。     

多冷却塔循环水系统的结构优化

对含有多个冷却塔的循环水系统进行研究，建立了多冷却塔循环水系统结构优化模型，用商业软件GAMS中NLP（非线性规划法）求解该模型，求解出操作费用最小时的匹配系数，并系统给出了最优结构；文章最后部分给出了详细的案例分析，将优化前后风机和水泵的电耗，补充水量，操作费用加以比较；结果表明，优化后风机和水泵的电耗，补充水量均有所降低，操作费用节约多达20％左右，优化效果明显。     

循环水冷却塔扩容技术研究

循环水冷却塔是以水为循环冷却剂,从系统中吸收热量排放至大气中,以降低水温的装置。其冷却原理是利用水与空气流动接触后进行冷热交换产生蒸汽,蒸汽挥发,利用蒸发散热、对流传热和辐射传热等原理散去生产中循环水的热量,来降低水温。此次改造通过对风机、填料、配水系统、收水器的更换,提高了冷却塔的处理效率,改造后通过测试达到预期目标。     

余热发电循环水加药系统技术改造

1改造背景我公司余热发电循环水加药(阻垢剂)系统自2007年建成使用至今已经10余年,设备老化、漏药严重,近几年故障频发,维修量及更换备件费用逐年加大,由于加药管道在室外,到冬季管道容易上冻,严重影响机组平稳运行.如果更换新设备,购买设备费用将近3万元,而且原厂家设计的循环水加药装置直接把阻垢剂通过柱塞泵打入循环水池,存在药品扩散慢的缺点,不利于阻垢剂充分发挥效果.鉴于此,车间组织电气、机械相关人员对循环水加药系统进行改造,使其能更好地满足生产需求.     

老成鼓循环水系统的络合化学清洗

我公司粘胶原液生产使用的KRl00老成鼓其循环水系统由循环管线、循环水泵、板式换热器、调温水槽组成。正常情况下一般水温与碱纤维素料温相差2～3℃。随着生产的运行,老成鼓鼓体内的水垢增多,老成鼓温度控制难度增加,主要表现在水温与老成鼓体内的碱纤维素温差增大且不成比例,特别是停车检修后重新运行,很难及时把料温调整到位。     

开阳化工循环水系统药剂筛选试验与研究

贵州开阳化工有限公司500kt/a合成氨装置配套2套循环水系统,其管道主要材质为碳钢、不锈钢及黄铜,设计循环水浓缩倍数>4,循环水系统补水为一次水.为缓解一次水水质恶化对设备产生的不利影响,并节约用水和减少药剂消耗费用,在保证各项指标正常的情况下,开阳化工通过一系列的循环水系统药剂筛选试验,筛选出了合适的药剂来提高循环...     

循环水闭式运行系统在石化行业的应用研究

循环水系统已成为石化行业节水降耗的关注重点。介绍了以闭式冷却塔为核心的循环水冷却系统及其运行过程中的注意事项,与开式循环水系统相比,闭式冷却系统具有水质优异、降耗节能的特点,节省水耗可达45%以上,有利于降低循环水系统运行费用、提高生产平稳性,在石化行业应用前景广阔。     

设计密闭循环水系统的几点技术措施

在某厂炼胶车间的设计中，我们依据该厂引进的法国米西林生产工艺的要求，将生产设备的冷却方式设计为密闭循环水系统。该系统具有水质要求高、水量和水压变化小、水温力求恒定、水的损耗少回收率高等特点，其系统如附图所示。为了使该密闭循环水系统更好地发挥它的优势，...     

中小型氯碱企业循环水利用探讨

介绍本厂循环水集中处理的工艺，其特点之一是对质量不稳定的循环水进行了水质处理以达到循环水再利用的要求；之二是采用横流钢结构冷却塔，保证水温降至生产工艺要求。该工艺使循环水利用率提高到８１％。     

无霜空气源热泵系统冬季除湿性能初步实验

通过对比现有的空气源热泵空调系统的优缺点，提出了一种新型无霜空气源热泵空调系统。该热泵系统最大的新颖之处在于热交换塔实现了“一塔三用”，不仅冬季可以无霜高效运行与再生，夏季蒸发冷却后性能也有所提升。通过搭建该系统实验平台研究了溶液塔入口空气温湿度、空气流量、溶液入口温度、溶液流量、溶液质量分数对除湿性能及空气出口温度与溶液出口温度的影响，结果表明：出口空气与溶液温度随入口空气温湿度、流量、溶液温度、质量分数的升高,溶液流量的下降而升高；溶液塔的除湿效率主要受风量和溶液流量的影响，而入口空气温湿度、入口溶液温度、溶液质量分数影响很小，溶液塔的除湿量随着室外空气湿度的升高、入口溶液温度的降低、空气流量和溶液流量的升高而升高。     

鲁奇甲醇生产装置的数学模拟和工况分析——(Ⅱ)鲁奇管式变换炉

建立了鲁奇甲醇装置中管式变换炉催化床的一维数学模型,模拟计算了变换炉催化床气体浓度、床层温度、冷管内气体温度分布,讨论了不同操作条件对变换率及床层出口温度的影响。     

Optimal temperature for DMFC stack operation

We report a model of heat transport in a fragment of DMFC stack consisting of a bipolar plate with the linear anode channel. The model takes into account fragment heating due to reactions and cooling by the flow in the anode channel and by water evaporation. The resulting system of equations is solved using asymptotic technique. The solution yields optimal inlet temperature of the anode flow, which provides uniform distribution of stack temperature. Physically, in this regime stack and flow temperatures are equal and local rate of stack heating is exactly compensated for by the local rate of cooling due to evaporation.     

聚丙烯环形反应器模拟与分析：（Ⅱ）动态特性和操作稳定性

建立了聚丙烯环形反应器动态数学模型,通过模拟计算,研究了工艺参数扰动时聚丙烯环形反应器的动态响应规律、反应器结构参数对动态特性的影响,并对冷却水流量和冷却水入口温度进行了动态操作稳定性分析。     

新型节水装置--闭式空冷循环冷却水系统的工业应用

根据传统的工业循环冷却水系统存在的水蒸发量大、出水温度不稳定、水质逐步恶化、排污量大、电耗高、维护费用高等现状,研究开发了一种新型节水装置——闭式空冷循环冷却水系统。介绍了该装置的冷却原理、工艺流程和主要设备。工业应用表明,该装置具有冷却水温度稳定、可提高工艺换热设备传热效率和使用寿命、节省电耗、排污量小、设备占地面小、维护简单、运转费用低等特点。经济效益测算表明,以水费2元／m^3、电费0．5元／kw·h计,使用寿命10年,该装置产生的直接经济效益为4230万元。     

Cooling Conditions of Ozone Generators

The efficiency of ozone generators is determined by many factors. Operating conditions such as feed gas quality and especially cooling conditions are of utmost importance. Cooling of ozone generators is absolutely necessary, since ozone destruction reactions increase exponentially with temperature. The most common way to cool an ozone generator is water flowing in close contact to the electrodes. The heat removal out of the discharge gap depends on different parameters. Electrical input power, cooling water flow conditions, electrode geometry and material properties are some of them. Simultaneously lowering cooling water temperature, applied power density and gap width, leads to a lower gas temperature in the discharge gap and thus to increased ozone production efficiency. Minimizing the temperature difference between the cooling water inlet and outlet improves the ozone production efficiency as well. This measure, however, results in high cooling water flows and requires additional cooling water chilling, resulting in higher operational costs and capital expenses. Cooling associated costs rise disproportionally with increasing cooling water flow. Simultaneously, energy consumption of ozone generators decreases as the average cooling water temperature goes down. As a result, there exists an optimum between the operational and capital expenses for the combination of ozone generator and cooling water system related expenses, offering significant cost savings for the customer.     

MINLP optimization of mechanical draft counter flow wet-cooling towers

In this paper, the problem of the optimal design of mechanical draft counter flow cooling towers that meets a set of specified constraints is formulated as a mixed-integer nonlinear programming (MINLP) problem. The Merkel's method is used to specify the characteristic dimensions of cooling towers, together with empirical correlations for the loss and overall mass transfer coefficients in the packing region of the tower. Water-to-air mass ratio, water mass flow rate, water inlet and outlet temperatures, operational temperature approach, type of packing, type of draft, height and area of the tower packing, total pressure drop of air flow, power consumption of the fan, and water consumption provide the set of optimization variables. The MINLP problem is formulated so as to minimize the total annual cost of the cooling tower. The performance of the proposed procedure is shown with the solution of six examples.     

Humidification-dehumidification desalination system driven by geothermal energy

The work presented in this paper focuses on desalinating sea water system using a humidification-dehumidification process as it is supplied with water heated by geothermal energy as clean and renewable natural resources of energy. Computer simulation of the behavior under various working conditions of the desalination system was carried out to predict the variations of key output. Such variables include the ratio of sea water mass flow rate related to air mass flow rate, cooling water temperature difference across the condenser, geothermal source inlet temperatures to the heat exchanger and the amount of produced distilled water. To validate the computer program, a comparison between the experimental and theoretical results was conducted, and a good agreement had been obtained. The result showed that, the optimum value of the ratio between sea water mass flow rate to air mass flow rate was found to be in the range of 1.5 to 2.5. Improvement in the fresh water productivity at the optimum ratio of sea water mass flow rate to the air flow rate was observed by increasing both the geothermal source inlet temperature and the cooling water temperature difference across the condenser.     

Optimization of Methanol Yield from a Lurgi Reactor

Methanol is an important chemical with the potential to become an alternative fuel. An optimization study was performed for a Lurgi methanol synthesis reactor using the commercial process simulator Aspen Plus. The optimization routine is coupled with a steady‐state model of the methanol synthesis reactor. Syngas inlet temperature, steam drum pressure, and cooling water volumetric flow rate were optimized so that methanol production in the reactor outlet was maximized. The methanol yield increased by 7.04 %.     

立式壳管式氨冷凝器自动除垢防垢技术

简述了常用的除垢方法 ,重点介绍了一种新的自动清洗技术———在每根冷凝管内悬挂一条特制的塑料螺旋纽带 ,利用冷却水带动纽带自转对管内污垢实行刮擦清洗作用。在某大型肉联厂初步的工业应用试验结果表明 ,安装纽带后冷却水进出口温度差比安装前提高了 2 7.5 %。