Bureau of Mines / Minerals yearbook: Metals and minerals 1978-79
Year 1978-79, Volume 1 (1978-1979)
Dikeou, James T.
Cement, pp. 153-191 ff. PDF (4.3 MB)
153Cement By James T. Dikeou1 Portland cement shipments from plants in the United States and Puerto Rico, including cement imported and distributed by domestic producers, totaled 83.8 million tons in 1978 and 83.4 million in 1979. Shipments in 1979 were 7% higher than shipments in 1977 but 4% less than the 1973 record high cement shipments of 86.6 million tons. Mill value of these shipments increased to $3.4 and $3.9 billion, respectively, for 1978 and 1979, 21% and 39% higher, respectively, than that of 1977. This reflects an increase in the unit value of $4.35 and $9.88 per ton respectively, for 1978 and 1979, or 12% and 27%, respectively, compared with that of 1977. Demand for cement during the 2-year period was strong in most end use sectors. Housing starts in 1978 remained high, at about 2 million units, dropping to 1.7 million units in 1979. In addition, nonresidential building exceeded expectations. Total cement sales in constant dollars rose 13% in 1978 and 17% in 1979 compared with 1977 sales. Much of the increased cement demand was west of the Appalachians. Cement production capacities in 1978 were not adequate to meet demand in many parts of the West and severe shortages were chronic throughout the year particularly in Washington, Oregon, California, and Arizona. Although production of cement for 1979 was about the same level as in 1978, the shortages of the previous year did not occur. During this 2-year reporting period, produàtion was affected by isolated strikes, conversion to coal burning, installation of pollution control facilities to meet environmental regulations, operating difficulties, shortages of special railcars, and the inability to raise capital for expansion of this capitalintensive industry. Over the previous 20 years, cement consumption had risen at an average annual rate of about 2.3%. This is a slightly higher rate than that of construction as measured in constant dollars. Contributors to the higher consumption of portland cement include concrete slip form payers for highway construction; the use of cement for slope protection in reservoirs; shotcreting for mine shaft-lining systems; concrete overlays on highways and airport runways as a means of rehabilitation, mainly since 1973; increased use of concrete rail ties; special admixtures permitting the manufacture of higher strength concrete; and wider use of prestressed and precast structures for industrial plants, box girders, bridge decks, and rapid transit systems. New cement plants being built or modernized are designed to minimize labor through the use of automated equipment. This factor has contributed to labor productivity gains in the cement industry where tons-per-employee-hour have risen from 0.9 in 1960 to 2.3 in 1979. During this period, portland cement manufacturing capacity increased from 81 million tons to 106 million tons in 1979. In contrast the number employed has dropped from 35,000 to 24,000. Several new capacities came onstream including one new plant, four modernizations, and expansions and the startup of a plant that was closed in 1976. Estimates of the capacity added is about 2 million tons; However, in geperal, capacity increases have been impeded by government legislation and regulation on both the Federal and State levels. Energy continued to be a major concern in the cement industry. In keeping with a trend set in motion by the fuel crises of 1974, a number of kilns were converted to coal as the primary fuel. In addition, several companies were experimenting with the burning of industrial wastes, waste oil, and a variety of combustible materials other than coal, oil, or natural gas. Another recent movement has been the acquisition
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