Embodiments of the present disclosure include a system, method, and apparatus comprising a direct steam generator configured to generate saturated steam and combustion exhaust constituents.

Provided is a superheated steam boiler. The superheated steam boiler, in this embodiment, includes an inner tank system, the inner tank system including a first wet tank and a second dry tank separated from one another by an isolation member, an outer sleeve at least partially surrounding the inner tank system, wherein one or more wet tank fluid openings proximate a lower surface of the first wet tank allow the first wet tank to be in fluid communication with the outer sleeve, and further wherein one or more dry tank steam openings in the second dry tank allow the second dry tank to be in steam communication with the outer sleeve, and a burner system located primarily within the inner tank system. The burner system, in this embodiment, includes a combustion/expansion chamber having one or more spherical surfaces located in and fluidly isolated from the first wet tank, a distribution chamber located in and fluidly isolated from the second dry tank, a plurality of heat tubes extending through the isolation member between the combustion/expansion chamber and the distribution chamber; and an exhaust tube extending from the distribution chamber and out of the inner tank system to exit the superheated steam boiler.

Provided is a superheated steam boiler. The superheated steam boiler, in this embodiment, includes an inner tank system, the inner tank system including a first wet tank and a second dry tank separated from one another by an isolation member, an outer sleeve at least partially surrounding the inner tank system, wherein one or more wet tank fluid openings proximate a lower surface of the first wet tank allow the first wet tank to be in fluid communication with the outer sleeve, and further wherein one or more dry tank steam openings in the second dry tank allow the second dry tank to be in steam communication with the outer sleeve, and a burner system located primarily within the inner tank system. The burner system, in this embodiment, includes a combustion/expansion chamber having one or more spherical surfaces located in and fluidly isolated from the first wet tank, a distribution chamber located in and fluidly isolated from the second dry tank, a plurality of heat tubes extending through the isolation member between the combustion/expansion chamber and the distribution chamber; and an exhaust tube extending from the distribution chamber and out of the inner tank system to exit the superheated steam boiler.

A modular boiler system for implementing fuel combustion is provided. The system includes a first boiler and a second boiler of a plurality of boilers, an oxygen input unit, a fuel input unit, a recycled flue gas input unit, and a flue gas separator. The first boiler receives oxygen from the oxygen input unit, fuel from the fuel input unit, and recycled flue gas from the recycled flue gas input unit. The first boiler outputs intra-system flue gas. The flue gas separator separates the intra-system flue gas into a first and second flue gas stream, transfers the first flue gas stream to the second boiler, and transfers the second flue gas stream to a gas cleaning system. The second boiler receives oxygen from the oxygen input unit, fuel from the fuel input unit, and the first flue gas stream from the flue gas separator.

A modular boiler system for implementing fuel combustion is provided. The system includes a first boiler and a second boiler of a plurality of boilers, an oxygen input unit, a fuel input unit, a recycled flue gas input unit, and a flue gas separator. The first boiler receives oxygen from the oxygen input unit, fuel from the fuel input unit, and recycled flue gas from the recycled flue gas input unit. The first boiler outputs intra-system flue gas. The flue gas separator separates the intra-system flue gas into a first and second flue gas stream, transfers the first flue gas stream to the second boiler, and transfers the second flue gas stream to a gas cleaning system. The second boiler receives oxygen from the oxygen input unit, fuel from the fuel input unit, and the first flue gas stream from the flue gas separator.

A process for in situ thermal recovery of hydrocarbons from a reservoir is provided. The process includes: providing an oxygen-enriched mixture, fuel, feedwater and an additive including at least one of ammonia, urea and a volatile amine to a Direct-Contact Steam Generator (DCSG); operating the DCSG, including contacting the feedwater and the additive with hot combustion gas to obtain a steam-based mixture including steam, CO.sub.2 and the additive; injecting the steam-based mixture or a stream derived from the steam-based mixture into the reservoir to mobilize the hydrocarbons therein; and producing a produced fluid including the hydrocarbons.

A process for in situ thermal recovery of hydrocarbons from a reservoir is provided. The process includes: providing an oxygen-enriched mixture, fuel, feedwater and an additive including at least one of ammonia, urea and a volatile amine to a Direct-Contact Steam Generator (DCSG); operating the DCSG, including contacting the feedwater and the additive with hot combustion gas to obtain a steam-based mixture including steam, CO.sub.2 and the additive; injecting the steam-based mixture or a stream derived from the steam-based mixture into the reservoir to mobilize the hydrocarbons therein; and producing a produced fluid including the hydrocarbons.

A modular pressurized combustion system for flexible energy generation is provided. The system comprises a plurality of pressurized combustion boilers, at least one compressor configured to provide pressurized oxidizer gas to each of the plurality of pressurized combustion boilers in parallel, and at least one feeder configured to provide fuel to each of the plurality of pressurized combustion boilers in parallel. The system further comprises a flue gas input unit configured to provide recycled flue gas to each of the plurality of pressurized combustion boilers in series, at least one pressurized heat recovery unit configured to receive a flue gas output stream from each of the plurality of pressurized combustion boilers, and at least one particle filter configured to filter a flue gas output stream from the pressurized heat recovery unit. The system also comprises an integrated pollutant removal unit.

A modular pressurized combustion system for flexible energy generation is provided. The system comprises a plurality of pressurized combustion boilers, at least one compressor configured to provide pressurized oxidizer gas to each of the plurality of pressurized combustion boilers in parallel, and at least one feeder configured to provide fuel to each of the plurality of pressurized combustion boilers in parallel. The system further comprises a flue gas input unit configured to provide recycled flue gas to each of the plurality of pressurized combustion boilers in series, at least one pressurized heat recovery unit configured to receive a flue gas output stream from each of the plurality of pressurized combustion boilers, and at least one particle filter configured to filter a flue gas output stream from the pressurized heat recovery unit. The system also comprises an integrated pollutant removal unit.

A boiler includes an upper steam drum, an optional intermediate drum, and a lower drum. Each drum is divided by an internal divider into a clean section and a concentrated section. Downcomers connect the upper steam drum to the lower drum, and tubes are connected to convey a heated steam-water mixture from the lower drum into the upper steam drum (through the optional intermediate drum, if provided). An optional superheater has an input terminal connected to receive steam from the clean section of the upper steam drum. An attemperator may be provided to attemperate superheated steam output from an output terminal of the superheater, and the attemperation fluid may optionally be provided from the concentrated side of the upper steam drum.