Cement Production in the Victor Valley
California’s cement manufacturing industry is a significant contributor to the state’s economy. In 1999, the state produced more than 13 millions tons of portland cement, valued at over 765 million dollars.
California has led the nation in cement production from 1958 to the present, with the exception of the 5 years between 1980 and 1985. Cement is California’s second most important mineral commodity, after construction aggregates, and PRESENTLY represents 25% of California’s annual mineral production. About 80% of the cement produced in California is consumed within the state, the rest is exported to the Pacific northwest, Nevada, Arizona, Utah and New Mexico.
Eight companies operating 11 plants manufacture cement in California. Reflecting both markets and geologIC CONDITIONS, eight of those plants are located in Southern California (see figure) and 3 are located in the Victor Valley. Those plants are TXI Riverside Cement, located in Oro Grande, Southdown Victorville Cement LLC,( formerly Southwest Portland Cement,) located in Apple Valley, and Mitsubishi Cement Corporation, located in Lucerne Valley. These plants together produce over 5.5 * million tons of cement annually,OR about % of California’s total production.
Cement is THE binding agent in concrete, mortar and other construction products, and has become essential to modern construction. There are several varieties of cement, the most widely used and produced is portland cement which accounts for most US cement production, It has been the dominant type produced in the United States for over 100 years.
The basic ingredients in cement are deceptively simple: lime or calcium oxide, (65%), silica or silicon dioxide (20%), alumina (4% to 5%), iron (3% to 4%), and calcium sulfate (4%). Limestone or marble provides the main ingredient, calcium carbonate, and the location of this ingredient generally determines the location of the cement plant. The Victor Valley cement plants are located near suitable deposits of limestone or marble. The other ingredients are provided by raw materials that are either mined nearby, or in another location and imported. These raw materials include natural materials such as clay or bauxite ( for alumina), quartzite, quartz sand or diatomite ( for silica), magnetite or hematite ( for iron). Recycled materials such as used refractory brick, diatomite filtering agents or slag CAN ALSO BE used for the silica and iron requirement in cement manufacture.
The basic recipe for cement sounds simple: after the raw materials are proportioned properly, grind all materials into a fine powder, heat to 2400 degrees Fahrenheit, until the new compounds form marble-like balls called clinker, cool, then regrind to a fine powder, adding calcium sulfate (to ensure workability of the concrete), and ship either in bulk or in bags.
Energy is the most expensive ingredient in portland cement manufacture. Large amounts of energy are consumed in cement production because of the high temperatures required in the kilns and the large volumes of material processed. The most common fuel in cement plants is coal, but coal is supplemented with alternative fuels including coke, waste tires, and sewage sludge. Some of these alternative fuels actually help reduce polluting emissions.
All cement companies make basically the same product so staying competitive involves many strategies. Cutting the costs of the raw materials is one way for cement manufactures to stay competitive. This involves carefully weighing the location, chemistry, physical form, transportation costs, and on-site storage and conveyance costs to produce a competitive product.
Many cement producers may cut costs by relying on a backhaul to transport necessary raw materials. A truck will haul a load of additive materials after delivering a load of cement.