Various embodiments disclosed herein include a system and method for processing an exhaust gas. The system comprises a regenerative thermal oxidizer (RTO), a bypass flow module in parallel with the RTO, and a mixing module disposed downstream of the RTO; wherein the RTO is configured to oxidize a first part of the exhaust gas and produce a hot tail gas and deliver a predetermined amount of the hot tail gas outside of the RTO, and the mixing module is configured to receive the predetermined amount of the hot tail gas; and wherein the bypass flow module is configured to receive and bypass a second part of the exhaust gas around the RTO into the mixing module; and wherein the second part of the exhaust gas absorbs sufficient heat from the predetermined amount of the hot tail gas in the mixing module for oxidizing and decomposing an organic compound therein.

Certain aspects of natural gas liquid fractionation plant waste heat conversion to simultaneous power and cooling capacities using modified Goswami system can be implemented as a system. The system includes a waste heat recovery heat exchanger configured to heat a buffer fluid stream by exchange with a heat source in a natural gas liquid fractionation plant. The system includes a modified Goswami cycle energy conversion system including one or more first energy conversion system heat exchangers configured to heat a working fluid by exchange with the heated buffer fluid stream, a separator configured to receive the heated working fluid and to output a vapor stream of the working fluid and the liquid stream of the working fluid, a turbine and a generator, wherein the turbine and generator are configured to generate power by expansion of a first portion of the vapor stream of the working fluid, and a cooling subsystem including a cooling element configured to cool a process fluid stream from the natural gas liquid fractionation plant by exchange with a condensed second portion of the vapor stream of the working fluid.

Methods of sequestering carbon dioxide (CO.sub.2) are provided. Aspects of the methods include contacting an aqueous capture ammonia with a gaseous source of CO.sub.2 under conditions sufficient to produce an aqueous ammonium carbonate. The aqueous ammonium carbonate is then combined with a cation source under conditions sufficient to produce a solid CO.sub.2 sequestering carbonate and an aqueous ammonium salt. The aqueous capture ammonia is then regenerated from the from the aqueous ammonium salt. Also provided are systems configured for carrying out the methods.

A device includes a desulfurization system which forms a hydrogen sulfide-containing acid gas; a system for extracting elemental sulfur and a hydrogen sulfide-containing tail gas as exhaust gas; a device for generating electricity and gypsum from the tail gas; and a gas line system for supplying acid gas from the desulfurization system to the system for extracting elemental sulfur and to the device for generating electricity and gypsum, and for supplying tail gas from the system for extracting elemental sulfur to the device for generating electricity and gypsum. The gas line system has a gas distributing apparatus which supplies acid gas solely to the system in a first position, supplies acid gas solely to the device in a second position, and supplies a first part of the acid gas to the system and a second part of the acid gas to the device in a distributing position.

CO.sub.2 capture processes and systems can be improved by recovering thermal energy from particular streams for reuse in the stripping stage. Thermal energy can be recovered from the overhead gas stream of a stripper operated under vacuum pressure conditions, and thermal energy can also be recovered from a flue gas. A heat transfer circuit can be implemented for recovering thermal energy by indirect heat transfer from the overhead gas stream, a flue gas stream, and/or other streams to a heat transfer fluid. The heat transfer circuit can include multiple heat recovery loops arranged in parallel and the heated fluid can be supplied through a reboiler of the stripper to heat the solution in the reboiler.

The present disclosure provides systems and methods that combine direct capture of one or more moieties from a gaseous mixture with one or both of calcium oxide production and power production. The systems and methods can utilize combinations of a capture unit, a regeneration unit, a calcination unit, a slaking unit, a heat exchange unit, a separation unit, and a power production unit. The present disclosure provides the ability to remove carbon dioxide and other moieties from air or other gaseous mixtures in a truly carbon negative manner by utilizing electricity from a power production unit that is operated in a carbon neutral or carbon negative manner and simultaneously provide useful products, such as calcium oxide and calcium hydroxide.

An energy-saving system using electric heat pump to recover flue gas waste heat for district heating uses flue gas waste heat recovery tower to absorb the sensible and latent heat in the high-temperature flue gas by direct contact heat and mass transfer. The circulating water is sprayed from the top and the flue gas flows upwards in the tower. The electric heat pump is indirectly connected with circulating water through the anti-corrosion and high-efficiency water-water plate heat exchanger. The return water of the heat-supply network enters the electric heat pump through the anti-corrosion and high-efficiency water-water plate heat exchanger and exchanges heat indirectly with the high-temperature circulating water. The electric heat pump uses the electric energy of the power plant as the driving power.

A carbon dioxide separation recovery method includes: bringing a particulate carbon dioxide adsorbent and a treatment target gas containing carbon dioxide into contact with each other to make the carbon dioxide adsorbent adsorb the carbon dioxide contained in the treatment target gas; and bringing the carbon dioxide adsorbent which has adsorbed the carbon dioxide and desorption steam into contact with each other to desorb the carbon dioxide from the carbon dioxide adsorbent, and thereby, regenerate the carbon dioxide adsorbent and recover the desorbed carbon dioxide. The step of recovering the carbon dioxide includes utilizing a recovery gas as a heat source of a heat exchanger, the recovery gas containing the desorption steam which has contacted the carbon dioxide adsorbent and the carbon dioxide which has been desorbed from the carbon dioxide adsorbent.

A counter-current cross-flow heat exchanger for heating a first gas and cooling a second gas, includes modules in fluid communication with one another, each module being positioned on a plane, the planes mutually overlapping. Conduits allow entry and exit of the first and second gases into and out of the exchanger. Each module has heat exchange plates, with heating and cooling faces. The plates are orthogonal to the module plane and parallel to define alternating heating and cooling spaces. The first gas crosses each heating space with a direction substantially parallel to the plane of each module and the second gas crosses each cooling space with a direction substantially orthogonal to the plane of each module. The cooling spaces between adjacent modules are in direct fluid communication. The heating spaces between adjacent modules are in fluid communication with one another by conduits/conveyors, creating a serpentine path.

A water treatment system and method. Influent water produced from an oil and gas production or the like is circulated in a multistage unit where the water is treated by degassing the water by saturating the water with air, stripping volatile compounds from the water, evaporating non-aqueous phase liquid petroleum from the water, repeatedly stripping and equilibrating inorganic carbons in the water, subliming semi-solids from the water, and breaking colloids in the water using continuous cavitation. Water from the multistage unit is clarified through floatation and sedimentation and biological material in the water is inactivated using irradiation. Water is then filtered before being provided as treated water for an application specific process such as electro desalination reversal, fracking reuse, or other wastewater recovery.