Optimized Production and Energy Conservation

The possibilities of energy conservation in a cement factory are great. At least two important energy waste sources can be identified: flue gas heat and electrical energy of fan drives. A study of the Cementa AB factory at Slite, Sweden (production 2.1 million ton/y) shows that even though considerable efforts already have been made in energy saving, the potential is still great. Thus it is estimated that about 40 MW of gas heat can be turned into 3.5 MW of electrical energy. By applying high-efficiency motor drives about 2 MW can be recovered from fan drives. These two sources correspond to a total annual saving of $2.5 million. An investment to recover this energy will be paid back in less than a year.