Research On The Method Of Measuring The Filling Degree Of Cement Kiln Based On Infrared Images

The core equipment in the production of cement is a cement rotary kiln, and the cement raw material enters from the rotary kiln feed end, followed by drying zone, preheating and decomposition zone, combustion zone and cooling zone a total of five reaction zones, finally the formation of clinker from the discharge end.The material filling degree is an important parameter to reflect the process of cement production, not only can reflect to the large amount of information and material in the kiln, the liquidity and other important characteristics, but also reflects the material calcination process of rotary kiln internal temperature of the material changes.Presently,the number of measurement methods of material filling degree in the literature are rare, due to the special structure of the rotary kiln, and the environment is relatively poor,full of dust and high temperature, making contact measuring method of filling degree subject to many restrictions.Therefore, it has important application value to study a non-contact material filling degree measurement method to improve the existing monitoring system of rotary kiln production process. presently, most of the cement plants use infrared camera to monitor the temperature of the cement rotary kiln, to prevent damage to prevent abnormal temperature of rotary kiln.The paper presents a simultaneous measurement of the material filling method of the calcining and cooling zone by using cement kiln temperature information.This method is simple and effective and does not need additional investment and hardware facilities.Firstly, combined with the structure of the cement rotary kiln and the main reaction mechanism of cement clinker calcining process, the paper describes the cement clinker calcination process, the existing material filling degree calculation method and its important research significance in detail, and carry on the deeper exposition to the basic principle of infrared temperature measurement system. Secondly, the infrared temperature monitoring system of a cement plant in Jiangxi was used to collect the infrared image data and other important information of operating conditions of the rotary kiln. And the obtained infrared image sequences were pretreated as follow: the infrared image information is transformed to the gray level information by using the relation between the temperature value and the gray value, which is beneficial to the analysis and processing of the following works; The surface temperature change of cement kiln is analyzed in order to determine the research area of the calcination and cooling zone. 143 groups of experimental data image sequences can be obtained after preprocessing. Finally, through the analysis of the experiment based oninfrared image sequences data of many days, a calculation method of material filling degree that can measure the calcining zone and the cooling zone simultaneously is proposed and implemented. The comparison and analysis between the calculated results and other calculation methods are carried out, which proves the feasibility and accuracy of the method.