A Computer-Based Kiln Shell Temperature Monitoring (Control) System

The principle of and experience in continuous and instantaneous monitoring of shell temperature level for a 3000 ton/day preheater kiln is described. The system primarily consists of a high-speed infrared scanner which measures the kiln shell temperature, a computer which transforms and analyzes the temperature measurements, and a graphical display screen/printer to show the results. With the system it is possible to determine the state of the lining and coating, i.e., the degree of lining wear, location and size of existing or developing hot spots, the location, extent, and uniformity of protective coating, as well as the location and geometry of material rings. The system was installed and commissioned during three weeks of November 1982, and the experience gained during the first 12 months of operation is discussed. Subsequent to system installation, kiln uptime between brick jobs has improved 11 percent and tonnage seven percent in excess of rated capacity produced regularly. Uptime could have been better, but a kiln shutdown was taken to rationalize clinker inventory. Although the scanner could not take credit for the improved kiln uptime, it was certainly a major contributor as, for the first time, the operators had accurate timely information about lining and coating conditions.