The interactions of grinding aids and quality conditioners are complex and you have to conduct trials to find the optimum additive and addition rate. The specialists in this area are Grace. If they cannot help you then perhaps Mapei? I think your wish to increase the 28 day strength by almost 40 per cent is too ambitious and that no additive can do this. You must continue with your trials to find the best possible additive and addition rate.

We always have problems to get masonry cement with 95 per cent passing the 200 mesh in a mill with an O-sepa separator. We have high Blaine numbers but low in fineness. Do you have any solution please?

I think you have a problem with different grindability for the clinker and limestone fractions of your masonry cement. The limestone is preferentially grinding and giving you the high Blaine, however the harder clinker remains coarse and is the reason for the high residue. The best solution would be to separately grind the limestone and blend with OPC to create the masonry cement.

We are facing problem of poor fluidity of cement while extracting cement from silo even with fresh cement stock. We are having only Ordinary Portland Cement grinding with no water cooling facility in mill. Cooling takes place only in O-sepa. Since the last two months we started water spray in mill inlet to control mill outlet product temperature of around 108 to 113 deg C. Product temp. entering to silo is around 85 deg C and at outlet 72 to 75 deg C. Humidity is around 40 to 60 per cent in air because of coastal area. Please highlight some of the possible causes for such phenomenon and also give the method normally applied to determine moisture content in cement. As additional information we are using mineral gypsum 5 to 5.5 per cent in the cement.