Research On Optimization And System Design For Power Coal Blending Process In The Thermal Power Plants

Thermal power is the main source of electric power resources, which takes more than 80% of the total power generated in the country. As the most important fuel for thermoelectricity generation, thermal coal accounts for 70%-80% of generation cost. There are abundant resources of coal in our country, but the regional distribution of them is very unequal, and there is great difference in coal quality among different regions. The coal quality deviates much more than the design of boiler, so that the service life of the coal-fired boiler becomes shorter. The study of steam coal blending optimization model can fully improve the utilization rate of low-cost low-quality coal and realize advantage complementation of coal resources. In addition, the study can not only reduce transportation cost through using local or nearby coal resources, but also save coal purchasing cost through reducing the purchase amount of high price coal. At the same time, the study can limit the SO2 emissions, thus achieve the goal of energy conservation and environmental protection.This paper analyzes the necessity and significance of steam coal blending in thermal power plants first, then introduces the present research status at home and abroad, including the development status of both blending techniques and blending software systems, and describes the characteristics of coal quality and combustion in detail. In addition, constraints and objective functions for coal blending were determined according to the actual requirements of the power plant. On the basis of these work, the coal blending linear mathematical models of single objective and multi-objective were established, which were solved by a software package called lp_solve and Multiple Objective Particle Swarm Optimization respectively, at the same time, a selection strategy for the multi-objective model results was formulated.Based on the above models and algorithms, the paper has carried out the system analysis and design, and developed the power coal blending optimization management system at last. Taking into consideration that the users of this system are most non-computer professional people, and the system will be used in the actual production environment of a power plant, user experience need to be paid more attention in the system development process, including operating conveniences, timeliness and operability. Based on the above requirements, the system has not only embed the two models mentioned before, but also realized basic data maintenance of coals, system management including users, roles and authorities, as well as statistical analysis for optimization results and so on. The system was developed with the integrated environment of both MyEclipse and Flash Builder and the Web server used by which is Tomcat, the database used by which is MySQL, the development frame used by which is Flex+Spring+Hibernate.The models, algorithms and system were verified by the practical problems of a certain power plant in our country. The result shows that the optimization schemes of coal blending which were obtained by the models the paper proposed are reliable and practical, which can meet the accuracy requirements of the thermal power plant on coal blending accuracy. At the same time, the system has friendly interfaces, high operating efficiency and strong maneuverability.