Performance of PAHs emission from bituminous coal combustion

Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion.     

燃烧火焰法在低碳钢沉积碳材料的观察

低碳钢基体经过240#~1 200#水磨砂纸研磨后,通过火焰法沉积碳材料,观察到组织具有一定缺陷碳纳米纤维沉积,平均长度为1um,长径比5~10,管径大小与研磨后基体上的催化剂颗粒大小相近。     

关于《燃烧热的测定》实验中热平衡计算式的商榷

本文证明用外壳等温式弹式量热计测定物质燃烧热时，在许多教材中长期使用的基本公式中存在错误，并对正确计算公式提出了见解．     

Simulation study on radiative imaging of combustion flame in furnace

Radiative imaging of combustion flame in furnace of power plant plays an increasingly important role in combustion diagnosis. This paper presents a new method for calculating the radiative imaging of three-dimensional (3D) combustion flame based on Monte Carlo method and optical lens imaging. Numerical simulation case was used in this study. Radiative images were calculated and images obtained can not only present the energy distribution on the charge-coupled device (CCD) camera target plane but also reflect the energy distribution condition in the simulation furnace. Finally the relationships between volume ele- ments and energy shares were also discussed.     

Study on the comprehensive combustion kinetics of MSW

The combustion behavior of typical components of MSW was examined with a thermal gravimetric analyzer (TGA). The experiments were done over the temperature range of room temperature to 1000℃ at a heating rate of 10 oC/min and in an oxidizing atmosphere. The results indicated that the entire weight loss process of each typical component of MSW consists of one to three distinct combustion stages. The combustion of typical components of MSW could be modeled by one to three independent reactions. The corresponding parameters of typical components of MSW such as activation energy, pre-exponential factor, and reaction order were determined. The calculated results using the comprehensive kinetic model composed of one to three independent and consecutive reactions, agreed well with experimental results.     

Knock prediction for dual fuel engines by using a simplified combustion model

INTRODUCTIONDuetodwindlingfueloilreservesandthedesireforreducedpollutantemissions,naturalgas,whichisdominantlycomposedofmethane,hasbeennowwidelyusedasanalternativefuelininternalcombustionengines .Aconventionaldieselenginecanbeconvertedwithoutexcessiveincr…     

燃烧加热污染空气对超燃冲压发动机性能影响研究

针对燃烧加热地面试验设备存在的工质污染问题,采用数值模拟方法研究了燃烧加热污染空气对氢燃料超燃冲压发动机性能的影响。以飞行马赫数Ma=6.5,当量油气比ER=0.6为计算基准状态,分别对纯净空气和污染空气来流下氢燃料超燃冲压发动机的整机流场和性能进行了对比计算分析。燃烧化学反应模拟采用了改进的H₂/O₂七组分八方程模型,湍流模型为标准的 k-ε模型,并采用直连式燃烧室试验数据进行了数值方法的验证。研究结果表明:(1)相对于纯净空气来流,污染空气来流下的超燃冲压发动机推力和比冲均有所下降。(2)采用酒精燃烧加热器的前提下,来流参数匹配静温、静压、马赫数时,发动机性能与纯净空气来流下的结果最为接近,而匹配总温、总压、马赫数时相差最大。(3)来流参数匹配总焓、静压、马赫数的前提下,采用氢燃烧加热器时发动机性能与纯净空气来流下的结果最为接近,而采用甲烷燃烧加热器时相差最大。      

微油点火技术浅析

主要介绍微油点火技术的原理、技术特点及组成等。     

影响回转烘干机技术性能的因素及技术改造

回转烘干机广泛应用于建材工业、化学工业及矿物烘干,分析了影响回转烘干机技术性能的两类因素,一类为由转筒烘干机本身引起的因素,另一类为烘干工艺方面的因素.同时提出技术改造措施.