Abstract: The improved production of sodium sulfate, potassium sulfate and other valuable salts from salt plant bitterns or the like wherein initial reduction in sulfate ion concentration yields salt cake and greatly facilitates the selective recovery of potassium and other valuable by-product salts. The process includes cooling the bitterns while below a certain concentration to produce glauber salt, followed by successive solar evaporation steps to yield harvestable potash salts. The salts are selectively treated and then refined by flotation. The flotation overflow is converted to potassium sulfate product by decomposition and crystallization steps and the underflow provides a recycle salt mixture for converting the glauber salt to salt cake.

Abstract: A salting-out process for recovering lithium from brines which have been concentrated by solar or thermal evaporation. Soluble sulfate salts are added to the strong brine solutions containing lithium to yield lithium sulfate monohydrate. Subsequent treatment of some residual brines with a strong acid will crystallize quantities of boron present as boric acid. Depending on the time of year and type of brine being used, a brine solar heating or plant evaporation system is provided to enhance the recovery processes.

Abstract: A method of obtaining energy in useful form utilizing complex geothermal waters as a source of energy, the method comprising the steps of initially maintaining pressure on the hot geothermal waters to prevent vaporization, directly contacting the hot waters with at least one immiscible working fluid to effect a transfer of the heat energy from the geothermal waters to the working fluid. The heat transfer contact is preferably made in a multiple stage counter-current contact centrifuge, mixer-settlers, or a column. Solid phase heat transfer between the water and fluid may alternatively be employed such as by the use of heat pipes. The heated working fluid is thereafter separated from the geothermal waters, subjected to multiple stage vaporization and the resulting vapors are channeled to a turbine or similar working device to produce electricity. The spent working vapors are cooled and/or condensed to be recycled within the system.

Abstract: A process for the recovery of chemical values from waste solids, wherein shredded waste solids are intermixed with hot char and a carrier gas in turbulent flow and passed through a pyrolysis zone under turbulent conditions at a temperature ranging from about 300.degree. F. to about 2000.degree. F., with zone residence time of under 10 seconds, with subsequent segregation and recovery of volatilized organic chemical values, char and inorganic chemical values therefrom.

Abstract: Solid trash is comminuted and classified into an organic fraction and a metals-inorganic fraction. The organic fraction is processed for recovery of paper pulp and the residue pyrolysed. The metals-inorganic fraction is processed for recovery of each major metal and inorganic constituent.

Abstract: Process for the gasification of coal in situ comprising driving shafts or tunnels into a coal seam, injecting air into the bore holes to ignite and burn the coal to raise its temperature ceasing the flow of air when the coal is hot enough to support the endothermic water gas reaction, and injecting steam into the hot coal formation, such steam preferably being preheated by the flue gases taken from the same end of the bore holes where the air was injected, and recovering product gases, including carbon monoxide and hydrogen, and also product oil, exiting the tunnel at the other end of the bore holes. When the temperature of the coal drops during injection of steam to a level which will just permit combustion, the steam flow is stopped, and the cycle is repeated by air injection and flue gas removal at the front end of the bore holes, and through the tunnel connected therewith. This cyclic process is repeated until the entire mass of coal within the area encompassed by the bore holes is exhausted.

Abstract: A method for obtaining solar energy in a useful form by utilizing solar ponds, the method comprising direct or indirect contact of hot liquid from the pond with a low boiling point immiscible working fluid for transfer of the heat energy from the liquid to the working fluid. Subsequently, the heated working fluid is separated from the liquid and flash evaporated to provide hot high pressure vapors which are led to a turbine or similar working device to produce electricity. The spent vapors are thereafter condensed and reused in the system. The solar ponds employ a covering agent to minimize evaporation of the liquid and thus provide for a maximum internal heat building. Additionally, light absorbing dyes may be added to the pond liquid to improve solar absorbing efficiency. The pond liquids may alternatively be used for a medium thermal requirement process or supplying heat source for a building structure.

Abstract: This application discloses a process for accomplishing in situ retorting of coal, or a similar hydrocarbon by constructing a substantially impervious retorting area, and then fragmenting the coal to provide a substantially homogeneous, porous mass. After pyrolysis due to the introduction of oxygen-containing gas at one portion and withdrawal of oil and gas at another portion, the direction of gas flow is reversed to convert the char into a relatively high B.T.U. gas product.

Abstract: An underground in situ oil shale retort, having predetermined boundaries, contains a bed of fragmented oil shale particles having an appreciable void volume distributed therethrough. Air passed through this bed of fragmented oil shale supports combustion of some of the carbonaceous material in the oil shale and provides heat for retorting oil therefrom. A number of such retorts may be formed in an area and pillars are left to support the overburden. Pillars forming walls between adjacent retorts also prevent gas leakage. Oil recovery from intact oil shale pillars is enhanced by fracturing the pillars as well as fragmenting the shale in the retort. The pillars are fractured by hydraulic fracturing, electrical fracturing, liquid explosive fissuring, or the like. The fractures are propagated from access holes in the vicinity of the pillars, typically between similar holes adjacent the next retort volume when the pillars are between retorts.

Abstract: A subterranean deposit containing oil shale is prepared for in situ retorting by initially excavating a plurality of vertically spaced apart voids of similar horizontal cross section located one above another within the deposit. A plurality of vertically spaced apart zones of unfragmented deposit are temporarily left between the voids, each unfragmented zone having a thickness of less than about 190 percent of the smallest lateral dimension of the voids above and below it. Explosive placed in each of the unfragmented zones is detonated, preferably in a single round to expand each unfragmented zone into the voids on either side of it and form a subterranean room containing a fragmented mass of particles having a void volume equal to the void violume of the initial voids. Retorting of the expanded mass is then carried out to recover shale oil from the oil shale.

Abstract: A cathodic bed of essentially inert, low cost silicon metal alloys in particulate form is used for the removal of ionic impurities from aqueous solutions by electrolytic deposition. The alloys used are substantially inert to the strong acid used to regenerate the alloy surface and remove the deposited metals.