Analyser helps cement maker Holcim to raise output and quality

Malvern, UK:  Cement producer Holcim is using an on-line particle size analyser, from Malvern Instruments, at its production site in Heming, France. The Insitec laser diffraction device is helping to optimise the grinding circuits that mill the finished cement.

In cement production, particle size is a critical parameter that has a direct impact on product quality. Laser diffraction techniques are used increasingly to meet the resulting requirement for particle size information. These are replacing the traditional technique of Blaine (surface area) measurement.

The Holcim plant had previously relied on off-line analysis in the laboratory. This required greater manual input and meant a delay of around 15 minutes between sampling and receiving results.

At the Heming site two identical grinding circuits operate in parallel. The Insitec samples each one alternately, providing particle size distribution data for each line every 10 minutes.

By continuously monitoring two parallel production lines, the analyser supplies the data needed to optimise throughput and at the same time produce high-quality cement.

The device is improving the performance of the finishing mills and it is a big help to the production teams, according to Michel Berger, chemist - instrumentation and environment specialist at Holcim.

“It provides continuous particle size data for the material exiting the mills, so that the operators can react quickly and confidently when making control decisions,” said Berger. “We now control the plant extremely closely and transition between different product grades very efficiently. As a result we have increased throughput and enhanced product quality.”