The World Cement Association (WCA) held its 'Energy efficiency and New Technologies' webinar yesterday with guest speakers from Sinoma Research Institute (SRI), CNBM group.



Nie Wenhai, assistant general director of SRI, presented a paper on milling technology that evaluated the power efficiency of grinding for raw and finish milling, replacing ball mills with roller press systems or vertical roller mills (VRM). Sinoma has completed 350 roller press installations and 531 VRM projects in the cement sector, consistently reporting power consumption falls of 50 per cent. 



An innovative grinding system that SRI has been developing is the External Circulation VRM system. It has recorded power consumption falls of 20 per cent and increases in output of 10 per cent over traditional grinding systems. This grinding system, which uses external bucket elevators to raise material up to the mill rather than fan power,  provides significant electrical power savings and a large pressure drop of 5000pa.

Ma Jiaomei, senior engineer and assistant director of SRI's Technology Application Dept, also presented research on improved efficiency and reduced energy consumption through a new pyroprocessing technology. The advances SRI have achieved have been in reducing heat consumption to 640kcal/kg clinker and power consumption to 18kWh/t clinker for the pyro-system. Due to the innovation of the technology and equipment, the preheater heat loss for exhaust gases and dust can be reduced from 150 to 120kcal/kg clinker, the surface heat loss reduced from 60 to 44kcal/kg clinker, and by improving the cooler technology it can increase cooler efficiency from 72 to more than 74 per cent, while reducing clinker exit temperatures from 150 to 95˚C.

SRI has also developed a Self DeNOx Calciner and the Sinowalk clinker cooler which have proved popular in China and southeast Asia.