射水抽气器代替射汽抽气器的经济分析

目前电厂常用的有射汽抽气器和射水抽气器两种。下面通过我厂的射汽抽气器改用射水抽气器的实例,对两种抽气器在电厂运行中的经济性、可靠性做一比较。     

射水抽气器改造的特性试验工作

射水抽气器由于具有众所周知的优点,已广泛用于火力发电厂汽轮机组。近年来国内正普遍进行射水抽气器的改造,用高效率的长喉型抽气器取代原短喉部抽气器,一般可节能35—50％,效益显著。改造抽气器必须进行特性试验,其方法正确与否对试验结果影响颇大。但是,目前关于如何进行实验方面的资料甚少,为了适应当前改造射水抽气器工作的需要,本文介绍了射水抽气器的特性及其长喉部抽气器的特性试验方法。文中所举的实例是我们通过对N125型机组长喉型射水抽气器的实际调试结果。     

影响射水抽气器性能的因素

射水抽气器效率高低、性能优劣不仅取决于射水抽气器本身的结构优化设计,还决定于其制造工艺及安装质量、工作条件等诸多因素.文中结合实践经验对这些影响射水抽气器性能的因素进行了分析.     

射水抽气器蚀损的原因及消除方法

汽轮机组现已广泛采用射水抽气器来抽吸凝汽器内的空气。在射水抽气器内流体的流速仅20余米,其值比射汽抽气器内的流速要小得多。但是射水抽气器内部件的蚀损速度比射汽抽气器要快得多。旧式射水抽气器的蚀损一般发生在如图1所示的三个部位。其中喷嘴进口A部及喉管进口B部的损坏系射流冲蚀所引起;扩散管上段C部的损坏系汽蚀所引起。由     

射水抽水器结构型式的探析

射水抽气器被广泛用作汽轮机凝汽真空系统的主抽气器,本文对短喉部和长喉部两种不同结构型式的射水抽气器在射流机理和能量损失等方面进行初步的探析,并通过试验数据和特性计算,对两种结构型式的射水抽气器的经济性进行分析分析,阐明了采用长喉部射水抽气器的优越性。     

射水抽气器结构型式的探析

射水抽气器被广泛用作汽轮机凝汽真空系统的主抽气器,本文对短喉部和长喉部两种不同结构型式的射水抽气器在射流机理和能量损失等方面进行初步的探析,并通过试验数据和特性计算,对两种结构型式的射水抽气器的经济性进行分析比较,阐明了采用长喉部射水抽气器的优越性。     

射水抽气器代替射汽抽气器的经济分析

目前电厂常用的有射汽抽气器和射水抽气器两种，下面通过我厂的射汽抽气器改用射水抽气器的实例，对两种抽气器在电厂运行中的经济性，可靠性做一比较。     

长喉管射水抽气器的试验研究和设计计算

本文介绍了国内外长喉管射水抽气器的试验研究简况和本所的试验研究、设计应用简况,并介绍了长喉管射水抽气器的结构、机理和合理的设计计算方法。应用结果表明,长喉管射水抽气器的经济性可比传统短喉射水抽气器提高二倍。     

射水抽气器系统的改进研究

本文指出了工作水温对射水抽气器的影响,分析了影响射水抽气器工作效率的几个因素,提供了多种可行的降低射水抽气器工作水温,提高其工作效率,降低汽机真空的方法。     

汽轮机射水抽气器的改进

汽轮机射水抽气器的改进闵行发电厂周文龙射汽式抽气器由于蒸汽消耗大、经济性能差，又有很大的噪声，故不少电厂已相继改成射水式抽气器。射水式抽气器的引射过程较复杂，如何获得最佳引射效果在理论研究和实践上尚难一致。几年来，射水抽气器喷嘴由单到多、喉部由短到长...     

Control and Use of Dual Fuel Systems in Forehearths, Glazers, and Lehrs

A solution to the curtailments of natural gas for the combustion systems of forehearths, glazers, lehrs, an other small burners used in the glass industry is reported. The solution lies in the use of oil-to-gas converters which are fully automatic, oil-fired air heaters that supply a precisely controlled flow of heated combustion air to the mixture manifold. Oil is atomized, vaporized, and delivered to the existing burners. The mixture of hot air and oil vapors has the same calorific value as the mixture of cold air and natural gas, and its combustion produces a blue flame characteristic of gas firing. This system has been used successfully in Mexico for the last two years in plants manufacturing containers, pressed table ware, opal borosilicate dinner ware, automatic paste mold ware, and hand blown glass.     

用热电冷联供方式节约能源

本文介绍了热电冷联合循环的原则性系统图及其工作原理，并结合实际着重论述了实现这一技术的供热、供冷系统。比较了蒸气压缩式制冷及溴化锂吸收式制冷两种方式。热电冷联供技术将成为节能的一条新的、有效的途径。     

新风量、新风品质及新风处理对室内空气品质的影响

分析了新风量、新风品质及新风处理对室内空气品质的影响,提出在热舒适基础上的可接受的室内空气品质必须考虑节能的需求,指出带热回收装置的新风预处理系统和独立新风系统是暖通空调系统的发展方向。     

Design, Installation, and Operation of Electrostatic Precipitators on Fluid Catalytic Cracker Flue Gas Applications

The function of electrostatic precipitators installed on fluid catalytic cracker flue gas lines is to remove the particulate matter as an air pollution control measure. This paper reviews significant steps involved in designing a particular precipitator installation, coordinating the construction effort, starting up and operating the system, and obtaining necessary results to satisfy the local air quality regulating agencies. The material presented is based upon experience gained from recent electrostatic precipitator installation projects in several refineries located across the nation.     

高频振捣对混凝土含气量、抗冻性和气泡参数的影响

采用水利水电工程常用的4种引气剂,配制水胶比为0.40、0.45和0.55的二级配混凝土.检测高频振捣对混凝土含气量和抗冻性的影响.结果表明,水胶比相同时,含气量损失率基本上随着高频振捣时间的延长而增大;高频振捣时间相同时,含气量损失率随着水胶比的增大而增大.水胶比为0.40时,掺加优质引气剂的混凝土的抗冻性对高频振捣并不敏感;水胶比为0.45时,高频振捣60s和90s后混凝土的抗冻性明显下降;水胶比增加至0.55时,混凝土的抗冻性随着高频振捣时间的延长迅速下降.同时,高频振捣对混凝土的气泡参数有明显的负面影响.根据试验结果,对混凝土的高频振捣时间提出要求,供施工参考.     

Decomposition of dilute trichloroethylene by nonthermal plasma processing-gas flow rate, catalyst, and ozone effect

Decomposition performance of dilute (100-1000 ppm) trichloroethylene (TCE) contaminated in air by using nonthermal plasma processing was studied to improve the decomposition efficiency. Three kinds of experiments were performed. One is the observation of the decomposition efficiency related to the processing gas flow rate. There exists an optimal gas flow rate for our reactor. The second experiment is the plasma decomposition performance observation related to the catalysts. Some catalysts, such as vanadium oxide (V/sub 2/O/sub 5/) or tungsten oxide (WO/sub 3/) on/in titanium oxide (TiO/sub 2/) pellets, improve decomposition performance. Indirect plasma processing (plasma processed pure air is mixed with TCE contaminated air) suggests the existence of very active oxidation radicals whose lifetime is more than a few minutes but details of them are not yet clear.     

光纤通道传送线路保护信号的方式及其分析

简介光纤通道纵联保护系统的组成,以及浙江省电网用光纤通道传送线路保护信号专用和复用的2种方式。同时分析了继电保护信号对传输延时、误码、同步质量要求的影响因素,并结合电网工程,利用SDH光纤系统传输保护信号,进行了500kV线路采用的复用光纤通道保护实例计算。     

Loss and recovery of hydrophobicity, surface energies, diffusioncoefficients and activation energy of nylon

The loss of hydrophobicity of nylon 6/6 caused by immersion in saline water for up to 336 h at different conductivities (0.005 to 100 mS/cm) and different temperatures (0 to 98°C) and its subsequent recovery in air (during 4500 h) have been investigated. The hydrophobicity is determined by measuring the static contact angle &thetas; between the tangent to a droplet of distilled water and the horizontal surface. The changes in the surface roughness and in the weight of the specimens were determined and correlated with the changes in the contact angle. It has been found that &thetas; decreased with increasing conductivity and increasing temperature of the saline solution. After removal from the solution, the higher the conductivity and temperature, the longer it took for &thetas; to recover in air. &thetas; decreased from 70° to 54° after nylon was subjected for 521 h to a uniform field of 15 kV_dc/cm in air. The surface free energy of nylon was determined as a function of time of immersion, the conductivity and temperature of the solution and during the recovery in air. The surface energies calculated for the virgin specimen are in good agreement with the literature. The diffusion coefficient of water into nylon increased from 0.23×10^-12 m²/s at 23°C to 7.4×10^-12 m²/s at 75°C. The activation energy was determined to be 59.4±2.2 kJ/mol. For unaged nylon the surface energies were determined at 23°C to be γ_S=44.7 mJ/m², γ_SD=29.3 mJ/m², γ_SH=15.4 mJ/m², W_SL =97.7 mJ/m² and γ_SL=19.8 mJ/m²      

SBWL-CFS燃烧系统中周界风、一次风及二次风混合特性试验研究

针对SBWL-CFS燃烧系统中周界风、一次风及其二次风混合特性进行炉内空气动力场试验研究,并对试验结果进行分析,为燃烧器安全稳定运行提供技术依据和运行参考。     

Effect of gas type on high repetition rate performance of a triggered, corona stabilised switch

This paper reports on the work undertaken to determine the effect of the gas type on the high repetition rate performance of a triggered corona stabilised (TCS) closing switch at a charging voltage of 23 kV. The voltage/pressure (V/p) characteristics as well as the ability of the switch to operate at high repetition rates were measured with SF/sub 6/, air and six different SF/sub 6//air mixtures having an SF/sub 6/ concentration ranging from 75 to 2% by pressure. The high repetition rate tests were conducted with a high-power facility at a pulse repetition frequency (PRF) ranging from 500 Hz up to a maximum of 3 kHz. During the investigation, it was found that for the given nonuniform switch geometry the high repetition rate performance of the device was closely associated with the efficiency of corona stabilisation, as measured from the V/p characteristics. This was clearly manifested by the superior performance of most of the SF/sub 6//air mixtures tested, which displayed a more efficient corona stabilisation compared to pure SF/sub 6/. In contrast, air displayed the worst performance of all the gases tested, due to the weak V/p characteristic and inefficient corona stabilisation.