Bonneville

BONNEVILLE (EN: Bonneville; RU: Бонневил) is the region of extraction of the potassium salts within the USA, within the Utah, Idaho, and Nevada states. It occupies the territory of the ancient lake, which existed during the Pleistocene epoch. The length is more than 500 kilometres, with the width of up to 230 kilometres, with the depth of 400 metres. The area is approximately 50 thousand square kilometres. More than 15 thousand years ago, it drained to the north, through the basin of the Snake river. The modern relics are the Little Salt, Sevier, Rush, Utah, and Great Salt lakes. There have practical significance the resources of salts from the Great Salt Lake, and from the Bonneville salt plain, which is located on the border of the Utah and Nevada states, within the region of the Wendover city. As the potential source of potassium, the brines within this region are known since the 1907. During the 1919, there has been performed the attempt of their industrial usage, and during the 1937, there has been started the issue of marketable produce, namely, of potassium chloride.

The Quaternary salt-bearing depositions of the plain have formed themselves as the result of the complete drying of the water body, which has not connected itself with the Great Salt Lake. They are represented by the salted silts, clays, oolitic limestones and gypsums. These depositions are overlain by the salt crust with the thickness of 1.5 metres, which is developed on the area of 380 square kilometres; down to the depth of 6 metres, there is contained within them the brine, which is having the industrial significance; they are underlain by the dense clay, below which there are embedded the lacustrine and fluvial depositions (420 metres). The brines are of the chloride type, are saturated with NaCl, and contain 1.0-1.5% of KCl. The salinity of the brines increases into the direction to the centre of the plain. They collect the brines into the channels with the depth of 6 metres, and with the total length of 150 kilometres. The brines are pumped from the channels into the primary evaporative pond (the area is 29 square kilometres), then into the intermediate pond, where proceeds the sedimentation of the major mass of halite, then into the sedimentary pond (2.03 square kilometres), within which there separates itself sylvinite, which contains 65% of NaCl, 32% of KCl, and 3% of MgCl2. The season of evaporation is limited to 90-100 days of the summer months. Sylvinite is collected by bulldozers into piles, is loaded into the hopper freight cars, and is transported to the plant, which is situated at the distance of 1.6 kilometres to the east from the Wendover city. The productive capacity of the plant is 66 thousand tonnes of K2O; the byproduct is MgCl2. The brine extracting facility and plant belong to the "Kaiser Aluminium and Chemical Corp." firm. During the 1981, there has been extracted 300 thousand tonnes of sylvinite. During the 1979, there has been completed the construction of the new brine extracting facility.