利用装置低温余热蒸汽伴热改热水伴热浅析

通过对蒸汽伴热和热水伴热耗量及散热损失的计算,对比研究了蒸汽伴热和热水伴热的散热损失。并本着就近解决的原则,充分利用原有伴热管线,提出了蒸汽管线改造方案并进行了实施。通过对两种伴热方式散热损失比较分析,以及对伴热用户量改为热水伴热后的节能分析,表明将蒸汽伴热改为热水伴热对降低生产成本,提高能源利用效率起十分重要的作用,对节能降耗具有深远的意义。     

仪表伴热的改造和维护经验

论述目前国内北方地区普遍采用的仪表蒸汽伴热、热水伴热系统 ,在设计、施工以及维护中的若干问题以及解决方案 ,同时叙述了在节能方面我们所作的一些工作和采取的一些措施     

仪表伴热的改造及维护

论述了目前国内北方地区普遍采用的仪表蒸汽伴热、热水伴热系统，在设计、施工以及维护中的若干问题以及解决方案，同时叙述了在节能方面所做的工作和采取的措施。     

蒸汽伴热改热水伴热节能分析

由于国际原油市场低迷,迫使我厂鉴于盈利和亏损边缘,因此平稳生产节能降耗是我厂创造效益的主要增长点。对于储运单元,蒸汽伴热造成能耗损失及经济损失尤为突出,如果将蒸汽伴热改为热水伴热会大大减少能耗损失及经济损失,一年将为我厂创造效益约270余万元,同时也将大大减少我厂的人工成本和设备损耗成本,为我厂节约了成本,做到了效益最大化。     

热带地区原油罐区蒸汽伴热改热水伴热分析

从蒸汽伴热管线设置、调节能力及对凝结水管网的影响方面分析热带地区原油罐区蒸汽伴热系统的缺陷,通过不同改进伴热方式特点及优缺点分析,提出伴热系统改进方法,并以处于热带地区的东方石化原油罐区伴热为例进行分析计算,得出蒸汽伴热改低温热水伴热时经济可行的结论。     

固定顶储罐内盘管蒸汽伴热工艺设计

本文首先对储罐常见的伴热型式及其适用范围进行对比分析;在此基础上,系统地介绍了固定顶储罐内盘管蒸汽伴热的工艺设计步骤,分别计算维持系统正常运行和出现极端情况时蒸汽使用量,为罐区公用工程蒸汽设计提供依据,最后采用极端加热情况进行伴热管规格设计。     

厂际管道伴热改造分析与设计

对厂际管道伴热改造项目进行了分析,对热水需要量及管道压降进行计算,以满足苯线在冬季运行时最低温度不低于10℃。节能效果从改造前蒸汽运行费用约82.81万元/a,降至现在的热水运行费用约0.76万元/a。     

油品工艺管道伴热介质剖析

通过对油品伴热介质电热、蒸汽、热水的分析、比较、计算,在不改变伴热线长度和管径的情况下,得出了热水不仅是维持低凝点油品管线伴热的理想介质,而且热水伴热节约大量能源的结论。     

大型煤化工项目全厂工艺外管伴热方案研究

蒸汽伴热是石油化工、煤化工工艺外管常采用的伴热方式,优点是来源可靠,使用方便,缺点是伴热温度调节困难,能耗高,冷凝水很难收集、处理,维修量大,特别是疏水阀更换率高,漏气严重。随着节能环保要求越来越高,许多企业采用工艺生产装置无法回收利用的热水、蒸汽冷凝液等低位热能,或电伴热,取得了较理想成果。     

浅谈如何经济地选用蒸汽伴热与电伴热

在化工装置中伴热系统虽然不能作为整个装置的主体部分,但是合理的选择本系统适用的伴热将对整个装置最经济的运转起到不可估量的作用。本文就化工系统中最常用的蒸汽伴热及电伴热的优、缺点做一比较,为选择最经济的系统用于化工生产提供参考。伴热的作用是在管道内没有流体的情况下防止管道冷却到低于要求的温度。这可以通过在管道保温层下放置热源来完成。化工装置中通常用伴热防止水管道的水结冰以及油管道的油温低于流点。最常用的两种伴热是蒸汽伴热和电伴热。在前些年大多数的伴热采用蒸汽伴热,但随着科学技术的不断发展,越来越多…     

Mechatronics using piezoelectric actuators

Mechatronics has enabled “intelligent” machinery such as car antiskid braking systems to be created. Any new automotive development has to incorporate a large number of mechanical servo functions, and the range of functions and requirements in servo technology is growing apace. New actuator technologies, therefore, give fresh impetus to product development and accelerate progress. Piezoelectric actuators represent a new technology that offers a host of advantages. In combination with signal-processing electronics, the good mechanical and electrical integratability of piezoelectric actuators make these devices key elements in innovative, intelligent systems. This paper presents prototype applications. Particular attention is focused on powerful large-displacement piezoelectric actuators. The article also includes concrete characterization of piezoelectric actuator elements. To this end specific static and dynamic measurement methods were developed to characterize the elements under temperature and load influences.     

Nickel electrodeposition using EnFACE

In this paper, the usefulness of EnFACE “maskless” technology to transfer millimetre and micro scale features of nickel has been described. Here, electrode position was used with a patterned tool (anode) and uncoated substrate (cathode) placed in an electrochemical reactor separated by a narrow gap i.e. 300 μm. It requires resistive electrolytes with low concentration of metal ions which leads to a reduction of material and chemical usage. An electrochemical cell with a volume about 500 ml was utilised. An electrolyte of 0.19 M nickel sulfamate was chosen and shown to be capable of depositing nickel. Millimetre and micron scale feature manually fabricated as well as micron feature prepared by using photolithography were used. Current density for nickel deposition was observed to be different for each feature area. Nickel was deposited at cell potential ranging between ?2.2 and ?2.4 V. A feature of 1 mm × 5 mm and features of 300–800 μm width have been successfully transferred. An increase in dimension of the deposited feature was observed due to current spreading. The features were broader at longer processing time and for smaller feature size. A thickness up to 0.54 μm was obtained for 125–600 s at a current efficiency ranged between 50 and 90 %. EDX and XPS analysis show that the nickel deposit was metallic. SEM analysis shows that the deposited nickel was dense and compact.     

Metal recovery using chitosan

Chitosan is a natural polycationic polymer which possesses valuable properties as a metal recovering and water purifying agent. Applications are —waste water treatment for heavy metal and radio isotope removal and valuable metal recovery, —potable water purification for reduction of unwanted metals, —agriculture—controlled release of trace metals essential to plant growth, —food—complex binding of iron in precooked food to reduce ‘warmed-over flavour’. The interactions of metals with chitosan are complex, probably simultaneously dominated by adsorption, ion-exchange and chelation. To study this it is of utmost importance to work with well characterized chitosans. This has been a problem as available characterizing methodology is limited. Degree of polymerization and deacetylation and the distribution of acetyl groups along the polymer chain is of crucial importance for chitosan metal interacting characteristics. Making chemical derivatives is a way to alter the metal interacting characteristics of chitosan. Chitosan possesses general coagulant/flocculant characteristics towards bio-molecules and surfaces.     

Metameric correction using parameric decomposition

The theory underlying parameric decomposition using a Cohen-Kappauf algorithm is explained. The decomposition is utilized to correct parameric color differences to metameric differences in order that indices of metamerism may be calculated from conventional formulae. The implications of the decomposition on the definitions of metamerism and of paramerism are discussed, and a physical realization of the fundamental stimulus is offered.     

Color correction using principal components

The problem of color correction for changes in illumination is briefly reviewed. A new method using the spectral reflectance distribution in the image is introduced and compared to a white-point mapping method. The new method is based on principal component analysis and thus is dependent upon the characteristics of the images that are to be viewed. These two methods are compared using chromaticity plots and the CIE L*a*b* ΔE measurement, for test samples which include color copiers, thermal writers, ink-jet printers, and lithography.     

Benzophenone reduction using sulphur-based additives

Pyrite and γ-Fe₂S₃ are the best of the mineral promotors tried for the CO—H₂O reduction of benzophenone to diphenylmethane. A mixture of ferrous sulphide and sulphur matches the promotional effect of iron pyrite, which implies that sulphur plays a role in the reaction. Both elemental sulphur and hydrogen sulphide are shown to promote CO—H₂O-induced reductions.     

Undercoat enamels using metallurgical slag

A composition of undercoat enamel for steel is developed, whose main material component is blast-furnace slag from Novolipetsk Steel and Iron Works. The main properties of the obtained enamel are determined, and the optimum conditions for the synthesis of a high-quality undercoat sheet-steel enamelare described.     

Reaction screening using a microreactor

This article discusses the screening of chemical reactions using a microreactor equipped with infrared spectroscopy as online analytics. An esterification reaction has been optimized in continuous mode with the proposed setup. The esterification did not work well due to the material of the microreactor (stainless-steel 316Ti) that catalyzed the decomposition of formic acid. However, despite the occurrence of decomposition, an optimization could be achieved with this system.