Methods and systems for removing volatile organic compounds from spent air are provided. The method can include oxidizing cumene in the presence of an oxidant to produce an oxidized product containing methanol and a spent air, separating the spent air from the oxidized product, contacting the spent air with an absorbent, an adsorbent, or a mixture thereof to remove at least a portion of any impurities in the spent air to produce a first purified air, and contacting the first purified air with a biological material to produce a treated air.

A natural gas dehydration system and method includes a contactor, a flash tank, and a still interconnected by a desiccant circulation system. A reboiler is coupled to the still and the flash tank to burn the flash gas from the flash tank and heat the desiccant. A secondary burner is associated with a vent stack of the reboiler to burn the flash gas from the flash tank when not firing the reboiler.

A hybrid method for capturing CO.sub.2 from a gas mixture is provided, comprising a step of contacting the CO.sub.2 containing gas mixture with a slurry consisting of a liquid medium, imidazole or imidazole derivative(s), and a metal-organic framework material (MOFs). For the slurry system, the mass fraction of the imidazole or imidazole derivative(s) in it ranging from 2 to 50% and the mass fraction of the metal-organic framework material in it ranging from 5 to 25%. In the technical solution provided in the present invention, through combining absorptive separation by the liquid solution in which the imidazole or imidazole derivative(s) is dissolved, adsorption separation by the MOF material suspended in the solution, and selective permeation separation by a liquid medium film forms on the outside surface of the suspended MOFs, an absorption-adsorption hybrid separation effect for CO.sub.2 gas mixtures is efficiently achieved. In the CO.sub.2 capture method provided in the present invention, conventional absorption separation and adsorptive separation technologies are effectively combined, furthermore, the addition of imidazole or imidazole derivative(s) substantially increases both the CO.sub.2 capture ability and capture amount of the MOFs/liquid slurry, showing a great potential in industrial applications.

Systems and methods for dehydrating a natural gas stream are provided herein. The system includes a lean solvent feed system, including a line from a topsides facility, wherein the line is configured to divide a lean solvent stream to feed lean solvent to each of a number of co-current contacting systems in parallel. The co-current contacting systems are placed in series along a wet natural gas stream, wherein each of the co-current contacting systems is configured to contact the lean solvent stream with the wet natural gas stream to adsorb at least a portion of the water from the wet natural gas stream to form a dry natural gas stream. A rich solvent return system includes a line to combine rich solvent from each of the plurality of co-current contacting systems and return a rich solvent stream to the topsides facility.

Plants, processes, and methods for reducing the H.sub.2S and CO.sub.2 contents of shale gasses from fields that produce shale gasses having varying H.sub.2S and CO.sub.2 contents are provided. Acid gas enters an absorber and is scrubbed using a lean physical solvent, producing a treated gas and a rich physical solvent. The H.sub.2S content of the treated gas is further reduced in an amine absorber, producing a pipeline gas and a semi-lean amine. The pipeline gas contains lower levels of H.sub.2S and CO.sub.2 than gas produced using a polishing bed. A physical solvent regeneration unit regenerates the lean physical solvent from the rich physical solvent for feeding into the absorption unit. An amine regeneration unit regenerates the lean amine from the semi-lean amine for feeding into the amine absorber. Contemplated plants may further comprise a Claus Unit or a Redox unit for oxidizing H.sub.2S to elemental sulfur.

A method for recovering methane gas from a landfill involves the use of a main absorber, a flash system, an optional ancillary absorber and an optional polishing absorber. The recovered gas is maintained at a temperature that enhances a solvent's ability to absorb carbon dioxide from the recovered gas. While the main absorber uses the solvent for absorbing most of the carbon dioxide from the recovered gas, the flash system removes much of the carbon dioxide from the solvent exiting the main absorber. In some examples, at least portion of the flash system operates at subatmospheric pressure to create a vacuum that draws in a generally inert stripper gas (e.g., air, nitrogen, etc.) at atmospheric pressure. The stripper gas helps remove carbon dioxide from the solvent in the flash system.

The invention discloses methods and apparatus(es) for the removal and control of pollutants such as gases and suspended particulates in the air of an enclosed space or an outdoor environment by passing the air through absorbent media. The absorbent media includes any liquid, solid or combination of liquid and solid media that is capable of absorbing a material in which it comes in contact. In one aspect of the invention, formaldehyde is removed by air sparging through a liquid such as water, optionally containing additional scavenging agents.

The invention relates to an absorbent solution and to a method of removing acid compounds contained in a gaseous effluent, comprising water and at least one of the following two nitrogen compounds belonging to the family of tertiary diamines: 1-dimethylamino-3-(2-dimethylaminoethoxy)-2-propanol

##STR00001## 1,1-oxybis[3-(dimethylamino)-2-propanol]

##STR00002##

A process for reducing the amount of CO.sub.2 released into the atmosphere with the exhaust gas stream produced by the combustion of a hydrocarbon fuel in an internal combustion engine (ICE) used to power a vehicle by capturing at least a portion of the CO.sub.2 in a liquid sorbent on board the vehicle, recovering the CO.sub.2 from the sorbent and compressing the CO.sub.2 for temporary storage on board the vehicle, where the process is operated as a semi-closed system in which the liquid sorbent that captures the CO.sub.2 serves as a working fluid and retains the CO.sub.2 during the power generation cycle to produce mechanical energy or work, after which the CO.sub.2 is desorbed for densification and recovery as an essentially pure gas stream and the working fluid is recycled for use in the process.

The present invention is directed to the removal of mercury in a gas dehydration process using thermally table chemical additives. In the process a complexing agent is added to a recirculated glycol solvent as part of the glycol solution feed to the dehydration liquid contactor and recirculated continuously with the glycol solvent. The complexing agent selectively reacts with mercury in the wet natural gas to remove the mercury from the dry natural gas product.