OCR Text |
Show 108 the brine. Because sodium chlorine, and sulfate are all present in much greater quantities than magnesium in Great Salt Lake brines, the weight percentage of magnesium in the brine is used as the indicator of the quality of brine. Pre- fill brines varied from about 0.35 percent to 0.60 percent magnesium, depending upon the Lake level and whether or not salt was precipitating. Since the fill was constructed, shallow South Arm magnesium concentrations have varied from 0.40 percent to 1.25 percent; deep South Arm brines from 0.75 to 1.50 percent; and North Arm brines from 1.00 to 1.25 percent. A graph showing the relationship of required pond area to magnesium concentration of the brine, assuming constant magnesium production, is given in Figure 20. Demand for magnesium has been growing but prices have been stable from 1956 to 1971. The rate of growth in demand is forecast at 6.2 percent per year through the year 2000. The supply, which comes mainly from sea water, is, for practical purposes, inexhaustible. The problem is to expand markets to meet available productive capacity. The increased demand for lighter economy cars due to the fuel crisis should have a favorable effect on the magnesium market. Dow Chemical Corporation has been the major producer during the post- World War II period, controlling from 80- 100 percent of the market. Recent developments have decreased production costs, and there is evidence to suggest that Dow Chemicals could sell for less. If so, it is likely that magnesium would be competitive with aluminum in price. It is expected that Utah's production of magnesium will remain at roughly one- fourth of the U. S. market ( its 1972 share) through the year 2000. At expected levels of production and assuming productivity of 14 |