Is low-heat portland cement still under patent protection?

Not here. The patent protection of low-heat portland cement began at 1930, with a patent protection period of 20 years, and the patent has expired. Low-heat Portland cement is a kind of cement with dicalcium silicate as the main mineral and low tricalcium aluminate content. It has the characteristics of low energy consumption, less harmful gas emission and low production cost. When producing this kind of cement, no admixture is allowed.