生物质固定床热解特性的试验研究与分析

对稻杆、稻壳、木屑在固定床热解反应器内的热解特性进行研究,考察热解反应温度和生物质种类对热解特性的影响,分析了热解产物的性质。结果表明,三种原料热解气的热值在１２０００￣１５０００ｋＪ／Ｎｍ＾３之间,可满足民用煤气的热值要求;产气率一般为０．２５￣０．４５Ｎｍ＾３／ｋｇ,其中稻壳的产气率最低;温度对热解产气率、生物油产率的影响很大,对热解气组份、热值、气流率及半焦产率影响也较显著;生物油的特性数据     

生物质废弃物在回转窑内热解研究--Ⅰ.热解条件对热解产物分布的影响

研究了生物质类废弃物在回转窑内的热解特性,讨论了物料种类,热解终温,加热方式,给料粒径和含水率对热解产物分布的影响。物料挥发份和热解终温高,加热快,粒径小,有利于燃气产率的提高以及炭产率的降低,而水分的提高会提高焦油的产率并降低炭的产率。同时,还研究了回转窑内的温升特性和热解气体的瞬态析出特性。     

SO2 emission characteristics and BP neural networks prediction in MSW/coal co-fired fluidized beds

The SO₂ emission characteristics of typical MSW components and their mixtures have been investigated in a Φ150mm fluidized bed. Some influencing factors of SO₂ emission in MSW fluidized bed incinerator were found out in this study. The SO₂ emission is increasing with the growth of the bed temperature, and it is rising with the increasing oxygen concentration at furnace exit. When the weight percentage of auxiliary coal is being raised, the conversion rate of S to SO₂ is largely going up. The SO₂ emission decreases if the desulfurizing agent (CaCO₃) is added during the incineration process, but the desulfurizing efficiency is weakened with the enhancement of the bed temperature. The fuel moisture content has a slight effect on the SO₂ emission. Based on these experimental results, a 12×6×1 three-layer BP neural networks prediction model of SO₂ emission in MSW/coal co-fired fluidized bed incinerator was built. The prediction results of this model give good agreement with the experimental results, which indicates that the model has relatively high accuracy and good generalization ability. It was found that BP neural network is an effectual method used to predict the SO₂ emission of MSW/coal co-fired fluidized bed incinerator.     

Induction-heating ignition of pulverized coal stream

Induction-heating ignition burner for the pulverized coal fired boiler is introduced. Some experiments were conducted on an experimental set-up, which includes alternative current power system, induction-heating system, pulverized coal and air supplier system, and measurement system to study the ignition process of coal powder and air mixture stream. Some results are presented. An industrial induction-heating burner for a 220 t/h boiler, which was designed on the basis of a series of researches, is described. This kind of oil-free ignition burner is characterized by its stable operation performances, and the lower cost in its maintenance.     

环保型增塑剂腰果壳油对丁腈橡胶性能的影响

研究了腰果壳油(CNSL)用量对丁腈橡胶胶料的硫化特性和硫化胶性能的影响,并与使用邻苯二甲酸二辛酯和环氧大豆油作为增塑剂进行了对比。结果表明,在0～30份(质量)用量内,加入CNSL后胶料的焦烧时间和正硫化时间有所缩短。与加入相同用量的邻苯二甲酸二辛酯和环氧大豆油的胶料及硫化胶相比,使用CNSL的胶料在硫化曲线上的最小转矩和最大转矩以及硫化胶的硬度、定伸应力和耐ASTM1#标准油体积增加率较小;硫化胶的拉伸强度、撕裂强度、扯断伸长率和耐ASTM3#标准油体积增加率较大;硫化胶的耐热空气老化性能较好。     

Experimental study of improved two step synthesis for DME production

Dimethyl ether (DME) has received growing attention due to its potential use as a multi-purpose fuel. A new technical route of improved two step synthesis is proposed for DME production, which is composed of methanol synthesis and methanol dehydration in a fixed-bed reactor. The influences of the operating conditions including reaction pressure, temperature, H₂/CO mole ratio in the syngas and space velocity on CO conversion, selectivity and yield of DME are investigated. CO conversion and DME yield both increase monotonically with the pressure increase. The optimal reaction temperatures for the synthesis and dehydration of methanol are different. CO conversion increases at first and keeps constant when the H₂/CO mole ratio is above 2. DME yield increases obviously and then decreases gradually with the space velocity increase. The optimal conditions are obtained to maximize the CO conversion and DME selectivity. The reaction temperatures of the top and bottom stage are in the range of 270-280 °C and 235-245 °C, respectively. The optimal ratio of H₂/CO is above 2, and the space velocity is in the range of 1000-1300 h^− 1.     

Filtration combustion characteristics of low calorific gas in SiC foams

This study investigated the combustion characteristics of low calorific gas in silicon carbide (SiC) foam. The temperature distribution, reaction zone, maximum temperature, and combustion wave propagation velocity were analysed at different inlet velocities, equivalence ratios of premixed gases, and pore densities. The temperature distribution near the reaction zone was determined by a time-based method. Super-adiabatic combustion was obtained in porous media under different conditions. The experimental results showed that higher temperatures were obtained in SiC foams of 30 pores per inch (PPI) than those measured for foam of 20 PPI. Increased equivalence ratio of premixed gases and pore density led to a thicker reaction zone and a higher preheating efficiency in the preheating zone. The combustion wave propagation velocity, which was less than 2 mm/s under these experimental conditions, was increased with increased inlet velocity and decreased equivalence ratio of premixed gases. The combustion wave propagation in foams of 20 PPI had the lowest velocity because of the good match of convection and radiation.     

基于Modelica/Dymola的小型燃气轮机建模与仿真

为了研究小型燃气轮机在不同环境下的动态特性,采用模块化建模方法,并根据质量和能量守恒原理,对小型燃气轮机进行了合理划分,建立了压气机、燃烧室、透平等单元部件的数学模型,并将这些部件划分为容积模块和流动模块.采用面向对象的、多领域的物理系统建模语言Modelica和Dymola编译器编制了各部件的仿真程序,建立了SmallGasTurbine通用模型库,以方便不同结构系统的小型燃气轮机的模型搭建.以川崎M1A-13D、M7A-01小型燃气轮机为例,搭建了它们的系统模型,将厂家给定基本数据与仿真结果进行了对比.研究结果表明,小型燃气轮机模型模拟仿真误差较小,具有很高的精确度.     

CCHP系统综合评价指标体系的信度与效度验证

基于冷热电联供(CCHP)系统初始综合评价指标体系,结合算例,对不同配置方案下初始综合评价指标体系进行信度与效度验证,获得了CCHP系统综合评价指标体系。     

2000年以来发布的有关暖通空调专业的部分国家标准和行业标准

列出了2000年以来发布的部分供暖供热、空调制冷、节能、通风除尘、洁净技术、计算机及网络技术、防火排烟、给水排水、减振降噪、环境保护、室内空气品质、材料与设备等标准．以及有关设计、验收规范和一些综合类标准。