The cement grinding application solution from Pavilion Technologies and the Insitec Fineness Analyzer from Malvern Instruments were installed to automate control and improve the efficiency of the finishing circuit that mills cement to the required fineness. Specific energy consumption - the amount of energy used to mill each ton of cement - is now 17% lower while the key performance indicator of one-day strength is up by about 15%. The company has estimated a return on investment of less than two years, based on energy savings alone.
“This project has transformed operation of the finishing circuit,” said John Murphy III, production manager, at Florida Rock Industries. “Together the technologies have revealed how to operate the plant in a very different, much more efficient way. We have reduced costs and have simultaneously improved product quality even though we are now targeting a much lower Blaine, the standard industry measure used to quantify fineness.”
Recognizing that cement strength and other aspects of cement performance correlate better with particle size parameters than with Blaine has been fundamental to the success of the project. The Insitec fineness analyzer provides continuous real-time particle size measurement at a rate of up to four complete distributions per second, reporting three specific size fractions to the control system. At the heart of the cement grinding application lies a powerful multivariate predictive control model that uses these data in combination with other routinely measured plant variables, to predict process behavior and provide closed loop control.
“This project highlights the synergy between advanced control packages such as the excellent offering from Pavilion and real-time particle size measurement,” notes Rob Norris, business line manager for Malvern’s process systems. “Using both technologies to fully optimize operation pays big dividends – as this installation clearly demonstrates.”
Further details of this installation and Malvern’s solutions for online particle size analysis for the cement industry can be found at www.malvern.com/common/downloads/campaign/MRK1244-01.pdf