Abstract: Systems and methods for variable rate steam injection, including via solar power for enhanced oil recovery, are disclosed. Several embodiments include using the variable nature of solar-generated steam to improve the efficiency and cost-effectiveness of enhanced oil recovery processes. In particular embodiments, the variable rate injection can provide more uniform steam distribution in an oil-bearing formation, at a lower cost than if the same amount of steam were provided on a continuous basis.

Abstract: Heat storage devices for solar steam generation, including recirculation and desalination, and associated systems and methods are disclosed. A representative method includes directing a high temperature working fluid (a) from a thermal storage device to a solar field to heat the high temperature working fluid, and (b) back to the thermal storage device. The method can further include directing a first portion of the high temperature working fluid from the thermal storage device through a first branch of a high temperature working fluid loop to transfer heat to a process fluid at a first temperature. A second portion of the high temperature working fluid is directed from the thermal storage device through a second branch of the high temperature working fluid loop, in parallel with the first branch, to transfer heat to the process fluid at a second temperature less than the first temperature.

Abstract: Systems and methods for selectively producing steam from solar collectors and heaters, for processes including enhanced oil recovery. A representative system includes a water source, a solar collector that includes a collector inlet, a collector outlet, and a plurality of solar concentrators positioned to heat water passing from the collector inlet to the collector outlet, a fuel-fired heater, a steam outlet connected to an oil field injection well, and a water flow network coupled among the water source, the solar collector, the heater, and the steam outlet. The system can further include a controller operatively coupled to the water flow network and programmed with instructions that, when executed, direct at least one portion of the flow through the solar collector and the fuel-fired heater in a first sequence, and direct the at least one portion or a different portion of the flow through the solar collector and the fuel-fired heater in a second sequence different than the first sequence.

Abstract: Separators and mixers for delivering controlled-quality solar-generated steam over long distances for enhanced oil recovery, and associated systems and methods. A representative method includes heating water to steam at a solar field, separating a liquid fraction from the steam, directing the steam toward a target steam user via a first, steam conduit, and directing the liquid fraction toward the target steam user in parallel with the steam via second, liquid fraction conduit. The method can further include mixing the liquid fraction and the steam before delivering the combined liquid fraction and steam to the target user.

Abstract: Systems and methods for variable rate steam injection, including via solar power for enhanced oil recovery, are disclosed. Several embodiments include using the variable nature of solar-generated steam to improve the efficiency and cost-effectiveness of enhanced oil recovery processes. In particular embodiments, the variable rate injection can provide more uniform steam distribution in an oil-bearing formation, at a lower cost than if the same amount of steam were provided on a continuous basis.

Abstract: Heat storage devices suitable for storing solar energy, and associated systems and methods are disclosed. A representative system includes a storage housing that contains a working fluid. A working fluid inlet pipe is coupled to the storage housing. A plurality of concrete plates are positioned in the housing, with the adjacent plates at least partially forming individual flow passages. A working fluid outlet pipe is coupled to the housing. A controller maintains a predominantly laminar flow of the working fluid in the flow passages. In some embodiments, the working fluid can be thermal oil having a boiling temperature of 300° C. or higher.

Abstract: Solar energy generates steam in a “once-through” configuration without recirculation, with closely managed steam quality, to produce wet steam from high-contaminant feed water without scaling or fouling. Feed water is pressurized, preheated, and evaporated in a series of pipes exposed to concentrated solar energy to produce a water-steam mixture for direct distribution to an industrial process such as enhanced oil recovery or desalination. Water flow rates are managed based on measurements of solar energy and steam production to manage variations in the solar energy. Steam generator piping system uses continuous receiver pipe that is illuminated by segmented parabolic mirrors enabled to track the sun. Provisions for steam generator piping recurring maintenance are provided. Thermal energy from hot condensate and/or from low quality steam is recaptured and warms inlet water.

Abstract: Techniques for purifying gases, and associated systems and methods are disclosed. A representative system includes an absorption vessel that can separate impurities from an input gas, a regeneration vessel that can release the impurities from the solvent, a rich solvent storage vessel, and a lean solvent storage vessel. The system can include a solar concentrator array and a thermal storage unit for storing the thermal energy generated by the solar concentrator array.

Abstract: Systems and methods for selectively producing steam from solar collectors and heaters, for processes including enhanced oil recovery. A representative system in accordance with a particular embodiment includes a water source, a solar collector that includes a collector inlet, a collector outlet, and a plurality of solar concentrators positioned to heat water passing from the collector inlet to the collector outlet, a fuel-fired heater, a steam outlet connected to an oil field injection well, and a water flow network coupled among the water source, the solar collector, the heater, and the steam outlet.

Abstract: Solar energy is collected and used for various industrial processes, such as oilfield applications, e.g. generating steam that is injected downhole, enabling enhanced oil recovery. Solar energy is indirectly collected using a heal transfer fluid in a solar collector, delivering heat to a heat exchanger that in turn delivers heal into oilfield feedwater, producing hotter water or steam. Solar energy is directly collected by directly generating steam with solar collectors, and then injecting the steam downhole. Solar energy is collected to preheat water that is then fed into fuel-fired steam generators that in turn produce steam for downhole injection. Solar energy is collected to produce electricity via a Rankine cycle turbine generator, and rejected heat warms feedwater for fuel-fired steam generators. Solar energy is collected (directly or indirectly) to deliver heat to a heater-treater, with optional fuel-fired additional heat generation.

Abstract: Techniques for subsurface thermal energy storage of heat generated by concentrating solar power enable smoothing of available energy with respect to daily and/or seasonal variation. Solar thermal collectors produce saturated steam that is injected into a producing or wholly/partially depleted oil reservoir that operates as a heat storage reservoir. Some of the saturated steam generated by the collectors is optionally used to generate electricity. Heat is withdrawn from the reservoir as saturated steam and is used to operate an active thermal recovery project (such as a producing thermally enhanced oil reservoir) and/or to generate electricity. Withdrawn heat is optionally augmented by heat produced by firing natural gas. The reservoir is optionally one that has been used for thermally enhanced oil recovery and thus is already warm, minimizing heat losses.

Abstract: Systems and methods for selectively producing steam from solar collectors and heaters are disclosed. A method in accordance with a particular embodiment includes directing a flow of water to a solar collector, directing the flow of water to a gas-fired heater, and, as a result of heating the flow of water at the solar collector and the gas-fired heater, forming steam from the flow of water. The method further includes changing a sequence by which at least a portion of the flow passes through the solar collector and the gas-fired heater.

Abstract: Solar energy is collected and used for various industrial processes, such as oilfield applications, e.g. generating steam that is injected downhole, enabling enhanced oil recovery. Solar energy is indirectly collected using a heat transfer fluid in a solar collector, delivering heat to a heat exchanger that in turn delivers heat into oilfield feedwater, producing hotter water or steam. Solar energy is directly collected by directly generating steam with solar collectors, and then injecting the steam downhole. Solar energy is collected to preheat water that is then fed into fuel-fired steam generators that in turn produce steam for downhole injection. Solar energy is collected to produce electricity via a Rankine cycle turbine generator, and rejected heat warms feedwater for fuel-fired steam generators. Solar energy is collected (directly or indirectly) to deliver heat to a heater-treater, with optional fuel-fired additional heat generation.

Abstract: Separators and mixers for delivering controlled-quality solar-generated steam over long distances for enhanced oil recovery, and associated systems and methods. A representative method includes heating water to steam at a solar field, separating a liquid fraction from the steam, directing the steam toward a target steam user via a first, steam conduit, and directing the liquid fraction toward the target steam user in parallel with the steam via second, liquid fraction conduit. The method can further include mixing the liquid fraction and the steam before delivering the combined liquid fraction and steam to the target user.

Abstract: The disclosed technology includes converting solar energy to thermal energy and delivering heat for use in a process. A representative method includes transferring solar energy to a working fluid and transferring energy from the working fluid to a heating element positioned inside a heating well. The heating well contains a thermal energy storage substance (TESS). A controller controls the heating element, which is in thermal communication with the TESS. In some embodiments, the TESS releases and absorbs heat as latent heat, which reduces temperature variation in heat exchange between the heating well and the formation surrounding the heating well. In such embodiments, the TESS is positioned between the heating element and an outer casing of the heating well. In addition to heating wells, the disclosed technology can be applied to other processes involving heat delivery.

Abstract: Systems and methods for variable rate steam injection, including via solar power for enhanced oil recovery, are disclosed. Several embodiments include using the variable nature of solar-generated steam to improve the efficiency and cost-effectiveness of enhanced oil recovery processes. In particular embodiments, the variable rate injection can provide more uniform steam distribution in an oil-bearing formation, at a lower cost than if the same amount of steam were provided on a continuous basis.

Abstract: Techniques for subsurface thermal energy storage of heat generated by concentrating solar power enable smoothing of available energy with respect to daily and/or seasonal variation. Solar thermal collectors produce saturated steam that is injected into a producing or wholly/partially depleted oil reservoir that operates as a heat storage reservoir. Some of the saturated steam generated by the collectors is optionally used to generate electricity. Heat is withdrawn from the reservoir as saturated steam and is used to operate an active thermal recovery project (such as a producing thermally enhanced oil reservoir) and/or to generate electricity. Withdrawn heat is optionally augmented by heat produced by firing natural gas. The reservoir is optionally one that has been used for thermally enhanced oil recovery and thus is already warm, minimizing heat losses.

Abstract: Systems and methods for selectively producing steam from solar collectors and heaters, for processes including enhanced oil recovery. A system in accordance with a particular embodiment includes a water source, a solar collector that includes a collector inlet, a collector outlet, and a plurality of solar concentrators positioned to heat water passing from the collector inlet to the collector outlet, a fuel-fired heater, a steam outlet connected to an oil field injection well, and a water flow network coupled among the water source, the solar collector, the heater, and the steam outlet.

Abstract: Heat storage devices suitable for storing solar energy, and associated systems and methods are disclosed. A representative system includes a storage housing that contains a working fluid. A working fluid inlet pipe is coupled to the storage housing. A plurality of concrete plates are positioned in the housing, with the adjacent plates at least partially forming individual flow passages. A working fluid outlet pipe is coupled to the housing. A controller maintains a predominantly laminar flow of the working fluid in the flow passages. In some embodiments, the working fluid can be thermal oil having a boiling temperature of 300° C. or higher.

Abstract: Techniques for purifying gases, and associated systems and methods are disclosed. A representative system includes an absorption vessel that can separate impurities from an input gas, a regeneration vessel that can release the impurities from the solvent, a rich solvent storage vessel, and a lean solvent storage vessel. The system can include a solar concentrator array and a thermal storage unit for storing the thermal energy generated by the solar concentrator array.