人才资源有效利用的测度问题探讨

本文主要从宏观层次上对人才资源利用水平定量评价方面进行了有益的探索。主要包括以下内容:1)界定人才资源有效利用的概念,研究其表现形式;2)探讨了人才资源有效利用的理论基础和分析模式:3)分析了人才资源有效利用的主要影响因素,构建人才资源有效利用的煤炉模型:4)

Study on mathematical model of steam coal blending

It is necessary to set up a new mathematical model of steam coal blending instead of the old model. Indexes such as moisture content, ash content, volatile matter, sulfur content and heating value in the new mathematical model have linear relation. The new mathematical model can also predict ash-fusion temperature precisely by considering coal ash ratio in steam coal blending, therefore it is possible to obtain linear relation of ash-fusion temperature between single coal and steam coal blending. The new mathematical model can improve precision of steam coal blending and perfect the old mathematical model of steam coal blending.

A novel model for cost performance evaluation of pulverized coal injected into blast furnace based on effective calorific value

The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal.

CFD Study of Ejector Flow Behavior in a Blast Furnace Gas Galvanizing Plant

In recent years, there has been a growing interest toward Blast Furnace Gas （BFG） as a low-grade energy source for industrial furnaces. This paper considers the revamping of a galvanic plant furnace converted to BFG from natural gas. In the design of the new system, the ejector on the exhaust line is a critical component. This paper studies the flow behavior of the ejector using a Computational Fluid Dynamics （CFD） analysis. The CFD model is based on a 3D representation of the ejector, using air and exhaust gases as working fluids. This paper is divided in three parts. In the first part, the galvanic plant used as case study is presented and discussed, in the second part the CFD approach is outlined, and in the third part the CFD approach is validated using experimental data and the numerical results are presented and discussed. Different Reynolds-Averaged Navier-Stokes （RANS） turbulence models （k-to SST and k-e Realizable） are evaluated in terms of convergence capability and accuracy in predicting the pressure drop along the ejector. Suggestions for future optimization of the system are also provided.

Three Dimensional Modeling of Pulverized Coal Combustion in a 600 MW Corner Fired Boiler

The three-dimensional code ESTET developed at the LNH has been used to predict the reactive flow in a 600 MW coal fired boiler. Assuming a no-slip condition between the gas and the coal, the equations for a gas-particle mixture can be written. The pulverized coal particle size distribution is represented by a discrete number of particle size groups determined by the measured fineness distribution. The combustion models taking into account the pyrolysis of the particle and the heterogeneous combustion of char have been validated using intensive measurements performed on the 600 MW utility boiler. Heat fluxes were measured along the walls of the furnace and satisfactory agreement between computation and measurements has been achieved in terms of maximum flux location and heat flux intensity. Local measurements of velocities using LDV probe, gas temperature and gas species concentrations were performed in the vicinity of one burner and compared with the computed variables. Again we have observed a good agreement between the computations and the measurements in terms of jet penetration, temperature distribution, oxygen concentration and ash content.

Numerical Modeling of Pulverized Coal Combustion at Thermal Power Plant Boilers

The paper deals with development and application the numerical model for solution of processes at combustion chamber of the thermal power plant boiler. Mathematical simulation is based on solution of physical and chemical processes occuring at burning pulverized coal in the furnace model. Three-dimensional flows, heat and mass transfer, chemical kinetics of the processes, effects of thermal radiation are considered. Obtained results give quantitative information on velocity distributions, temperature and concentration profiles of the components, the amount of combustion products including harmful substances. The numerical model becomes a tool for investigation and design of combustion chambers with high-efficiency and reliable operation of boiler at thermal power plants.