浅谈再循环系统的安全运行问题

1.前言 为了保护省煤器的安全运行,低、高、中压锅炉均有再循环系统,囚省煤器有两种:一种是沸腾式(即钢管式);另一种是非沸腾式(即铸铁式),前一种用于高、中压锅炉,后一种用于低压锅炉。     

(火用)平衡及其在化工节能中的应用

一、问题的提出众所周知,能量不能创造,也不能消灭,只能从一种形式转变为另一种形式,从一种物质传递到另一种物质。能量在数量上是守恒的。这就是热力学第一定律,即能量守恒和转化定律,它是能量平衡的基础。     

手工钨极氩弧焊接在我厂的应用

一、氩弧焊技术的应用概况锅炉和压力容器制造时,经常会碰到管子的拼接以及管子与法兰、端盖的对接焊缝(如图1),在焊接工艺上,我们采用过两种工艺方案,一种是单面手工电弧焊,一种是改变焊     

一种高效的热管式采暖系统

美国Hanford工程公司研制了一种高效燃气热管式家用采暖系统。这种采暖系统的特点是结构简便、效率高。它的主要部件是一种高效的加热炉,包括一种设计讲究的热管式热交换器和一种电动鼓风机及其控制器,采用控制器可将燃气的供给量减少75％,     

竹木复合胶合板效益显著

竹木复合胶合板是在新型改性胶粘剂研制方面取得重大突破的基础上,成功将竹材和木材两种纤维材质迥然不同的原材料进行胶合,并通过一系列生产工序加工制造的一种复合材料。竹木复合胶合板充分兼有竹材的弹性好、强度高、硬度大和木材的塑性好、密度低、易加工等特点,是一种性能优异的复合材料。竹木复合胶合板属于一种新型的人造板材,     

栽菇·沼气·肥料

我们从一九八一年以来试验了一种用稻草先栽培凤尾菇,后将菌床草进行沼气发酵、沼渣作肥料的综合试验方法,现介绍如下:凤尾菇是一种腐生性食用菌,分解纤维素、木质素的能力很强,在纯稻草、棉子壳、木屑和蔗渣中均能生长发育.它是一种营     

过热蒸汽用于织物定型初探

一、概述热定型机是印染行业内一种高耗能设备,所用热源有电、蒸汽、导热油、热风等.为了节能和提高生产的机动性,部份热定型机能同时接受二种热源,其中一种为主要热源,另一种为辅助热源.在国内已有的热定型机中,蒸汽均不能作为主要热源.若能把过热蒸汽作为热定型机的热源或主要热源,与其它热源比较具有洁净、安全、节能、成本低等优点,效益无疑是明显的.本文介绍浙江省绍兴市丝绸炼染厂利用过热蒸汽做热定型机热源的实践经验.     

地热资源

正地热资源是指贮存在地球内部的可再生热能,一般集中分布在构造板块边缘一带,起源于地球熔融岩浆和放射性物质的衰变。地热资源是一种十分宝贵的综合性矿产资源,其功能多、用途广,不仅是一种洁净的能源资源,可供发电、采暖等利用,而且还是一种可供提取溴、碘、硼砂、钾盐、铵盐等工业原料的热卤水资源和天然肥水资源,同时还是宝贵的医疗热     

管座的窄间隙GMA焊接

前言窄间隙(以下称狭坡口)GMA焊接方法不仅是一种生产效率高、成本低、焊接接头性能优良的焊接方法,同时又是一种节省材料和能量的好方法。因此,它早已在许多领域里得到广泛使用。在研究各种狭坡口焊接方法期间,根据不同的特点而采用不同的方法,但从适用对象来看,纵焊缝、环焊缝接头可以说是属于比较简单的一种焊缝形状。换言之,这两种     

基于核磁共振技术的牙膏含氟量测量方法

核磁共振是一种物理现象,作为一种分析测试手段在许多领域都有着极为广泛的应用,如地质勘探、石油化工、食品农业等。应用核磁共振技术对牙膏中的含氟量进行测量方法研究,包括应用相对测量、实验原理方法以及相关细节。目的是运用一种新的方法来快速便捷地测量工业生产中牙膏的含氟量,并分析此方法的优缺点、精度和误差。     

High-speed, high-horsepower electric motors for pipelinecompressors: available ASD technology, reliability, harmoniccontrol

At a time when the US natural gas pipeline infrastructure needs to be upgraded with new high-horsepower compressors to meet additional capacity demands, there exists an electric motor technology suitable for the task. The power electronic adjustable speed drive (ASD) controlled electric motor offers superior economics of initial, operating and maintenance costs compared to natural gas powered equipment. Natural gas pipeline deregulation is causing pipeline operators to evaluate electric drives as an alternative to gas driven equipment. This paper provides a needed summary of the potential for load building that is being offered to the electric power industry by the economics of the deregulated natural gas transmission industry. The gas transmission industry needs to upgrade equipment for more capacity. The new high speed electric motor technology discussed in this paper provides means for upgrading, at a fraction of the life cycle costs of conventional gas powered equipment     

An actively controlled fuel cell/battery hybrid to meet pulsed power demands

This paper presents the experimental results of an actively controlled fuel cell/battery hybrid power source topology that can be widely used in many applications, such as portable electronic devices, communication equipment, spacecraft power systems, and electric vehicles, in which the power demand is impulsive rather than constant. A step-down DC/DC power converter is incorporated to actively control the power flow between the fuel cell and the battery to achieve both high power and high energy densities. The results show that the hybrid power source can achieve much greater specific power and power density than the fuel cell alone. This paper first demonstrates that an actively controlled hybrid with a 35 W hydrogen-fueled polymer electrolyte membrane fuel cell and a lithium-ion battery pack of six cells yielded a peak power of 100 W, about three times as high as the fuel cell alone can supply, while causing a very limited (10%) weight increase to the whole system. After that, another hybrid source using a different battery array (eight cells) was investigated to further validate the control strategy and to show the flexibility and generality of the hybrid source design. The experimental data show that the hybrid source using an eight-cell battery supplied a peak power of 135 W, about four times that of the fuel cell alone. Finally, three power sources including the fuel cell alone and the two hybrids studied were compared in terms of specific power, power density, volume, weight, etc. The design presented here can be scaled to larger or smaller power capacities for a variety of applications.     

垃圾焚烧发电项目余热锅炉中参数和高参数的对比分析

垃圾焚烧发电厂蒸汽参数的选取直接影响垃圾焚烧发电厂的发电效率和收益,提高蒸汽参数成为提高发电效率的重要途径。根据对国内主流垃圾焚烧发电项目投建方和设备厂家的调研及理论分析,对中参数和高参数项目在技术特点、设备投资、维护成本、经济收益等方面进行了比较研究。采用高参数余热锅炉的项目,其设备成本和运营维护成本均较高,但发电量收入增加显著;项目的处理规模越大,采用高参数的经济收益越明显,设备投资静态回收期越短,经济优势越明显。     

出口核电项目核主泵国产化历程回顾和展望

  目的  随着我国核电产业“走出去”战略的推进,对核电装备自主供货的要求也越来越高,特别是在当下中美贸易摩擦的背景下,更加要求核心装备的国产化。  方法  以我国出口核电站核心设备——反应堆冷却剂泵国产化的顺利实现为例,就高端装备的国产化路线和方法做一些探讨。  结果  反应堆冷却剂泵（核主泵）是技术难度最高和最复杂的压水堆核电站核岛主设备,其作为两用物项同时也是出口管制设备。我国在出口核电项目上,依托国内迅猛发展的大型装备制造业能力,顺利实现了核主泵的国产化。  结论  核主泵的国产化打破了发达国家对核主泵供货的垄断地位,夯实了我国作为核电装备制造业强国的地位,也为未来其他高端核心装备的国产化提供了可供借鉴的经验。     

Development and testing of a prototype of low-power water–ammonia absorption equipment for solar energy applications

This article outlines the development and testing of a prototype of a water–ammonia absorption system designed for solar-powered refrigeration in small rural operations. The objective is to design a 2 kW refrigeration equipment for isolated areas with a high level of solar radiation to meet refrigeration requirements. The equipment has been designed to operate with a concentrating solar power system to obtain the required temperatures. The heat exchangers, which act as condensers, as well as the absorber and evaporator, are all made of galvanized steel piping having fins. The design uses natural convection; the generator and energy-saving heat exchanger have a multi-tubular arrangement and a transfer tank is used in place of a pump for displacing the ammonia solution. All of the operations are manually controlled. Overall, the test results showed unsatisfactory operation of the equipment having low efficiency. Nevertheless, the proposed objectives have been met and it is evident that with several important modifications the equipment will operate satisfactorily. In conclusion, based on the development phase, it is apparent that future prototypes must be more compact and more efficient.     

船用蒸汽动力装置控制监测系统的研制

蒸汽动力装置系统复杂,设备多,需要控制的参数多,大部分被控对象的特性无法用简单的数学模型来表示,装置运行时参数间相互关联,耦合关系复杂,许多被控参数用简单的单回路控制无法满足使用要求。而船用蒸汽动力装置负荷变化频繁,且变化辐度大,其控制系统的技术难度大。本文作者介绍了某船用蒸汽动力装置集中控制监测系统的组成,功能及系统的创新点。     

Application of flywheel energy storage equipment in vital places

飞轮储能设备在重要场所,可以被用于支撑大功率负载。应用时,需充分考虑供电系统的电能质量指标,电能质量可以系统地用各种指标描述。本文首先介绍了电能质量的国家标准,其次介绍了几类较常见的电压敏感类用电设备。最后介绍了一个案例,案例显示飞轮储能设备在重要场所带大功率敏感用电设备时,其输出稳定可靠。     

Energy sources for the future dismounted soldier,the total integration of the energy consumption within the soldier system

At present, the energy supply for the electronic equipment of the soldier is problematic. Each component has its own battery pack. These battery packs are not interchangeable and each requires its own charger. Furthermore, because they are all dimensioned to deliver the peak power for each item of equipment, this leads to a higher battery weight than necessary.It is expected that the system of the future soldier will use a central power source to supply the energy for all the different components. An energy bus will be integrated within the soldier’s system for this. The different components will generate their required voltages from the bus voltage by using high efficiency dc/dc converters. The use of an energy bus with local voltage conversion will facilitate inter-operability between different forces. The energy sources can easily be exchanged.For the near future, batteries are still considered to be the best option for the energy source. Rechargeable batteries are preferred above non-rechargeable ones due to logistic and environmental problems. For the long-term replacement of batteries, the direct methanol fuel cell (DMFC) is considered a viable option.Several different battery packs were tested for their capability to supply both the required energy and power during a 24 h mission. The tests were carried out with a controlled power method, as maximum power should be deliverable during 10% of the operation time.     

Front Cover

Next-generation control equipment for the transmission grid was installed in 2001 at a New York Power Authority (NYPA) substation as part of a project that will increase power flow transfer limit by 240 MW, approximately enough electricity for more than 200,000 homes. The project is the result of long-term collaborative research with EPRI, Siemens, and numerous energy companies including NYPA, Tennessee Valley Authority (TVA), and American Electric Power (AEP). The new control equipment, called a convertible static compensator (CSC) is quietly revolutionizing the way electricity is transported and controlled on the US National power grid, updating the grid to the standards needed to meet the demands of the electronic revolution while benefiting the environment by reducing the need to build new transmission lines.     

一种用于电力系统通信电源功率因数校正的方法

电力系统中的通信电源设备从相控式整流器已逐步被高频开关整流器所代替,针对这种情况提出了一种通信用高频开关电源升压电路。