Labor and Energy Issues in Cement Manufacturing from the 1st Cement Industry Technical Conference to the 50th

Increases in labor and energy efficiencies from the 1^st Cement Industry Technical Conference to the 50^th Cement Industry Technical Conference are impressive. Production has expanded from 577 less efficient kilns producing 56 million metric tons of cement to 178 kilns producing 91 million metric tons of cement. The average energy used has declined from 9.70 MBTU (million British Thermal Units) per ton of clinker to 4.375 MBTU per equivalent [metric] ton with the lowest reported energy values dropping from 3.5 MBTU per ton of clinker to 2.74 MBTU per equivalent [metric] ton. Productivity has increased from 0.714 metric tons per employee hour to 2.97 metric tons per employee hour. The factors behind this change, and prospects for further efficiencies, are examined in this paper.