History of cement - Understanding Cement- manufacturing cement ,While Johnson used the same materials to make Portland cement as we use now, three important developments in the manufacturing process lead to modern Portland cement: Development of rotary kilns Addition of gypsum to control settingThe manufacturing process - CEMBUREAUCement 101 ; The manufacturing process; The manufacturing process. Quarrying raw materials. Crushing. Raw meal grinding. Preheating. Precalcining. Clinker production in the rotary kiln. Cooling and storing. Cement grinding.