1999-12-15_GENERAL DOCUMENTS - M1999051

Home Browse Search

4 operation is that they have not created a cavity of a commercial size. So, they show potential but one section could be leaching out, say 10 times faster than another. It may mine out and you would not get the recovery. You've got two or three such thin, rich zones where solution mining could take off but the bulk of your nahcolite is still retained in the oil shale. You've got to get more recovery. You've got to get a reasonable diameter —full height of the resource to get something workable. In the mining of that individual well, not only are we worried about the efficiency of the operation and the shape of the cavity, we also are very concerned about the impurities that are natural in the ground, are soluble and come to the surface influencing the process. Our process, to be commercial, needs to produce a marketable product. Moving toward the animal kingdom, dairy cows are the primary nonhuman consumption market segment. This material can not be talcum powder, or farmers won't buy it. The material handling characteristics are very important to the marketability of the product. When we did pilot work at the bulk sample operation in 1983 -84, we bought a crystallizer from the leading crystallizer expert out there, Swenson Crystallizers. We ran for 3 months and never made a proper size crystal. All we made was talcum powder for 3 straight months. They had a process engineer in there working side by side with me for 2 of those months. They also had a dozen engineers in the plant back in Chicago advising over the phone. Not once did we get a commercial product—with 3 months of experimental crystallization. The experts weren't the help anticipated. Later, we developed our own crystallization for Industrial Resources and took it to the field. The first 6 months of operating the new crystallization failed to achieve commercial production. After failing for 6 months, we found a way to get these crystals to grow. Then, there were weeks of production with crystals too large. We finally got control of it, but only for a 6 -month period. After that, each day it became harder and harder to grow these crystals. There was some impurity, likely in a few parts per million, which we were unable to identify by assay, that changed, inhibiting the growth of the crystals. Following an extended trial and error research, we found an additive to counteract whatever happened. The importance of the additive was huge. Prior to its use, &large volume of material shipped was being rejected. In large part due to natural impurities, solution mining nahcolite and crystallization of competitive sodium bicarbonate is unpredictable and as much art as science. You don't just go down in the ground and get this product out. Natural impurities can prevent successful solution mining. Sound research and development is necessary. In nahcolite solution mining, the critical impurities can be organic or inorganic and have been unpredictable. They are known to change with location and depth in the basin. They are known to change with cavity temperature and injection liquor chemistry. I mentioned my experience at White River Nahcolite. With the original mix of natural impurities, initially we found mechanical controls to made the crystallization process work. This success slipped away over a period of time as we were increasing cavity temperature and mining new cavities. We could not determine if we lost a natural positive impurity or gained a negative one. We did not know why it changed. We could not tell if it was organic or inorganic. We could only guess it was something in the 10 to 200 ppm range. We were unable to detect the shift by assay. To add to the confusion, some organics present in the solution were constantly molecularly in flux as they are acted upon by the solution in a process called