Abstract: Disclosed is an improved method of producing potassium chloride by concentrating a brine thereof with respect to potassium chloride by multiple stage evaporation conducted at progressively higher temperatures, thereby precipitating other salts and thereafter cooling the brine in multiple stage crystallizers operated at progressively lower temperatures, thereby precipitating potassium chloride crystals. The improvement comprises cooling the brine in hotter crystallizer utilizing streams to or between cooler evaporators whereby in addition heat is provided to the evaporator stream.

Abstract: The invention disclosed herein relates to solution mining soluble ore deposits by creating a cavity substantially entirely filled with a deep bed of rubble. Solvent introduced at the top of the cavity is permitted to percolate downwardly through the rubble and is withdrawn near the bottom of the cavity. More specifically, the invention relates to selective solution mining generally horizontal beds of sylvinite, i.e., a mixture of crystals of halite (NaCl) and sylvite (KCl) wherein water or salt brine is washed down a generally vertical bore hole into the deposits and recovered enriched with dissolved KCl.

Abstract: Disclosed is an improved method of solution mining a mineral from a subterranean deposit thereof, where an aqueous solvent is introduced into the deposit and a solution enriched in the mineral is withdrawn from the deposit through a conduit which traverses a water bearing formation which overlies the deposit. The improvement comprises establishing through the wall of the conduit communication between the water bearing formation and the conduit to effect dilution of the enriched withdrawn solution thereby avoiding plugging of the conduit caused by crystallization of the mineral.

Abstract: Disclosed is a method of increasing the solution mining rate of potassium chloride from a cavity in a subterranean ore deposit containing potassium chloride and sodium chloride, in which cavity ore has been rubblized to effect a large contact surface area, by (1) solution mining the ore rubble at a first temperature for a time sufficient to determine the mining rate at that temperature; (2) increasing the temperature of the cavity solution to a temperature determined to be near the highest temperature at which the invariant composition is achievable at the solvent dissolving rate; and (3) solution mining the ore at the higher temperature.

Abstract: Subterranean formations of water soluble salt deposits are solution mined by introducing into the formation an aqueous solvent having a temperature substantially above the temperature of the deposit thereby heating the deposit and dissolving the soluble salts, and withdrawing from the deposit an aqueous solution enriched in the dissolved salts. An aqueous solvent having a temperature lower than the temperature of the first solvent is subsequently introduced into the deposit thereby recapturing heat given up to the deposit and dissolving the soluble salt utilizing greater solubility characteristics of the soluble salts owing to the increased deposit temperature, and withdrawing from the deposit a substantially increased amount of dissolved salt.

Abstract: Disclosed is an improved method of concentrating an aqueous solution containing a first salt and a second salt, the solubility of the first salt increasing more with increasing temperature than the solubility of the second salt, by multiple effect evaporation, wherein the multiple effect evaporators are backward fed, wherein the first evaporator effect is the hottest, wherein second salt is precipitated during evaporation, wherein the concentrated mother liquor is forwarded to a zone operated at atmospheric pressure, and wherein mother liquor effluent from the zone operated at atmospheric pressure is forwarded to a zone wherein the first salt is recovered.

Abstract: Disclosed is an improved method of separating a first salt and a second salt from an aqueous solution containing both salts and salt impurities, where the solubility of the first salt increases more with increasing temperatures than the solubility of the second salt, and at least a portion of the salt impurities precipitates as slower settling rate crystals than the settling rate of precipitated second salt. The solution is passed through a series of evaporators in which second salt and salt impurities are precipitated. The bottom of each evaporator communicates with an elutriation leg into which precipitated salts settle, and into which a fluidizing liquid is introduced to carry precipitated salt impurities back to the evaporators and from which second salt slurry is withdrawn.

Abstract: Disclosed is an improved method of recovering a salt having a solubility which increases with increasing temperatures from a multiple salt aqueous solution also containing a salt having a solubility which increases less with increasing temperatures than the solubility of the salt to be recovered. The solution is subjected to multiple effect evaporation having a plurality of evaporator effects operating at progressively higher temperatures. In the improved method, a means is provided whereby the mother liquor effluent overflow from the hottest evaporator effect is saturated with the salt to be recovered. Additionally, solution being concentrated in other effects having at least one preceding cooler evaporator effect may be allowed to become saturated with respect to the salt to be recovered. A slurry of the salt having a solubility increasing less with temperature is withdrawn from all effects.

Abstract: Disclosed is an improved method of concentrating an aqueous solution containing a first salt and a second salt, the solubility of the first salt increasing more greatly with increasing temperatures than the solubility of the second salt, by multiple effect evaporation, wherein the first evaporator effect is the hottest, mother liquor effluent overflow from cooler evaporator effects is forwarded to hotter evaporator effects, mother liquid effluent overflow from the first evaporator effect is forwarded to a zone maintained at atmospheric pressure and mother liquor effluent from the zone maintained at atmospheric pressure is forwarded to a first salt recovery step. In the improved method, the first evaporator effect is operated at super atmospheric pressure and at least 4.degree. C.

Abstract: Disclosed is an improved method of concentrating with respect to a first salt an aqueous solution containing the first salt and a second salt, the solubility of the first salt increasing more with increasing temperatures than the solubility of the second salt, by multiple stage evaporation at progressively higher temperatures and backward feed, wherein first salt and second salt is precipitated in an evaporator stage which communicates with an elutriation leg, wherein an aqueous slurry containing first salt and second salt is withdrawn from the elutriation leg and wherein the concentrated solution is forwarded to a step where the first salt is recovered. In the improved method, slurry withdrawn from the evaporator stages is leached with raw feed and/or mother liquor from this step in which the first salt is recovered to dissolve first salt from the slurry and return the dissolved first salt to the evaporator effect.

Abstract: Disclosed is a method of disposing solid sodium chloride while selectively solution mining potassium chloride from a subterranean deposit containing potassium chloride and sodium chloride. In this novel method an aqueous solvent saturated with respect to sodium chloride, unsaturated with respect to potassium chloride and slurried with solid sodium chloride, is fed into the deposit having a cavity wherein there is face on which rich and lean potassium chloride ore is exposed. Potassium chloride is thereby dissolved while sodium chloride is deposited from the solvent slurry and the resultant solution withdrawn from the cavity enriched in potassium chloride.

Abstract: Method of removing alkyl lead from air and other gases by contacting said air or other gas with at least a catalytic amount of lead dioxide at temperatures in the range between 60.degree. C. and 225.degree. C.

Abstract: Well completion apparatus is prepared in such a manner that a first metal element and a second metal element of the apparatus will have the capability of acting as a galvanic couple when contacted intimately with an electrolyte. During a sufficient amount of time of contact with the electrolyte, the first metal element will sacrificially corrode providing a passageway for flow of fluids between the interior and exterior of a conduit disposed in a well bore.