Research On Drum’s Water Level Control Methods Of Waste Heat Boiler In Sinter Plant Of Baosteel

Drum’s water level control technology is an important factor to restrict continuous and stable operation of the boiler. As there is large difference in diversity and ability of boiler, there is also large difference in water level control method. It presents various features, from simple to complex, and from basic to sophisticated.As the rising of environmental consciousness, waste heat boiler in sinter plant has been listed as one of the most important equipments for energy conservation and environmental protection. Whether the boiler can work smoothly or not depends mostly on the water level control of drum. If we can well control the water level, the boiler can run continuously.To further improve the drum’s water level control performance, and basing on the improvements of it in Baosteel, this thesis makes relative researches on drum’s water level control method, further explores more effective methods, and tries to find a more suitable method. This thesis mainly includes the following parts:(1) It briefly introduces drum’s water level features, and makes analysis and comparison between conventional control methods for water level.(2) It changes the two impulse control into three impulse computer control, since two impulse control used in waste heat boiler of baosteel sinter plant can not meet the need of big boiler water level control, It also gives detail description to the improvements from the perspective of expected target, core description and systematic features.(3) It applies fuzzy control method to solve the problems in improving process. Firstly, it introduces the basic ideas of fuzzy control, and compares it with the conventional control method, and also introduces its system structure and working principle. Secondly, it builds fuzzy control model and makes fuzzy design, and through simulation analysis and comparison to simulate improvements in the response speed of water level control, and reduction in the dynamic error and the control effect of "false water level". And lastly, it analyses and summaries the actual running results in working.Although the technology for boiler water level control is already mature, still there are evident shorts in application of it in industrial practice. This thesis, from the perspective of actual problems in drum’s water level control of waste heat boiler in Baosteel does relative researches on water level control methods, and makes analysis and comparison to the advantages and disadvantages of various methods, and raises a method, which is more convenient to practice and easier to implement, and is also more accurate and effective. And ultimately it achieves the purpose of improvements in control effects, and has made contribution for energy saving in sinter plant of Baosteel.