A modular gas processing system built with various gas processing modules and cubes improve transportability and customization. Individual gas processing modules and cubes can be included or removed in multiple combinations for customization because each module has a common interconnection point for connecting to any other gas processing module and cube.

A gas processing system for recovering methane gas from a landfill includes a high pressure main absorber plus a relatively low pressure one. The low pressure absorber receives a gas stream from an equally low pressure flash tank. This low pressure gas stream consists mostly of carbon dioxide and methane. The methane would normally be lost due to the high cost of recompressing the carbon dioxide, but by running this mixture of carbon dioxide and methane through the low pressure absorber with a slip stream of cold absorbent, a large portion of the carbon dioxide can be removed with negligible methane losses. The remaining methane can be recycled through the high pressure main absorber without having to recompress the removed portion of carbon dioxide.

A process for producing methanol includes the following steps (a) reacting, via a catalytic partial oxidation (CPO) reaction, a CPO reactant mixture (hydrocarbon, oxygen, and optionally steam) in a CPO reactor to produce syngas including H.sub.2, CO, CO.sub.2, H.sub.2O, and unreacted hydrocarbons; and wherein the CPO reactor includes a CPO catalyst; (b) introducing the syngas to a methanol reactor to produce a methanol reactor effluent stream (methanol, water, hydrogen, carbon monoxide, carbon dioxide, and hydrocarbons); and (c) separating the methanol reactor effluent stream into a crude methanol stream, a hydrogen stream, a CO.sub.2 stream, and a purge gas stream. The crude methanol stream comprises includes methanol and water; wherein the purge gas stream includes carbon monoxide and hydrocarbons; and the CO2 stream includes at least a portion of the CO2 of the methanol reactor effluent stream; and (d) recycling at least a portion of the CO2 stream to the CPO reactor.

A water gas shift reaction is carried out on a feed gas comprising carbon monoxide to produce carbon dioxide and hydrogen gas. The feed gas is split into multiple input streams flowed into respective reactors coupled in series. Steam is supplied to the input stream fed to the first reactor. The shift reaction is carried out in each reactor, with an overall reduced consumption of steam relative to the amount of gas shifted. The water gas shift reaction may be performed in conjunction with removing acid gas compounds from a process gas such as, for example, syngas or natural gas, by flowing a feed gas into a desulfurization unit to remove a substantial fraction of sulfur compounds from the feed gas and flowing the resulting desulfurized gas into a CO.sub.2 removal unit to remove a substantial fraction of CO.sub.2 from the desulfurized gas.

Methods and systems are described for more effectively sequestering or removing mercury from flue gases. This is accomplished by feeding an adsorbent into the flow of flue gas in ductwork leading into a scrubber housing containing a wet scrubber composition and providing a residence time sufficient to enable the mercury to be sequestered by the adsorbent.

Provided are apparatus and systems for performing a swing adsorption process. This swing adsorption process may involve passing an input feed stream through two swing adsorption systems as a purge stream to remove contaminants, such as water, from the respective adsorbent bed units. The wet purge product stream is passed to a solvent based gas treating system, which forms a wet hydrocarbon rich stream and a wet acid gas stream. Then, the wet hydrocarbon rich stream and the wet acid gas stream are passed through one of the respective swing adsorption systems to remove some of the moisture from the respective wet streams.

The present invention relates generally to the field of emission control equipment for boilers, heaters, kilns, or other flue gas-, or combustion gas-, generating devices (e.g., those located at power plants, processing plants, etc.) and, in particular to a new and useful method and apparatus for: (i) reducing the levels of one or more gas phase selenium compounds and/or one or more other RCRA metals, or RCRA metal compounds (regardless of whether such other RCRA metals or RCRA metal compounds are in the gas phase or some other phase); (ii) capturing, sequestering and/or controlling one or more gas phase selenium compound and/or one or more other RCRA metals, or RCRA metal compounds (regardless of whether such other RCRA metals or RCRA metal compounds are in the gas phase or some other phase) in a flue gas stream and/or in one or more pieces of emission control technology; and/or (iii) capturing, sequestering and/or controlling one or more gas phase selenium compound and/or one or more other RCRA metals, or RCRA metal compounds (regardless of whether such other RCRA metals or RCRA metal compounds are in the gas phase or some other phase) in a flue gas stream prior to desulfurization and/or in one or more pieces of emission control technology prior to one or more desulfurization units,

A method for treating an offgas produced in the processing of a renewable feedstock, includes hydrotreating a renewable feedstock to produce an effluent having a hydrotreated liquid and a vapour phase. The effluent vapour phase contains hydrogen, carbon dioxide, hydrogen sulphide and carbon monoxide. The effluent is separated into a liquid stream and an offgas streams. The offgas stream, containing carbon dioxide and hydrogen sulphide is directed to abiological desulfurization unit where a majority of the hydrogen sulphide is converted to elemental sulphur and a CO2-rich gas stream is produced.

A process for treating a flue gas produced in at least one upstream unit operating at a nominal operating pressure, the flue gas containing from 5 mol % to 90 mol % of CO2 on a wet basis and being at a pressure between 0.5 and 2 bar absolute. The process includes treating, via at least one downstream treatment unit, all or virtually all of the stream of flue gas originating from the upstream unit or upstream units, thereby producing, from the flue gas, a gaseous or liquid stream rich in CO2 which contains more than 50 mol % of CO2. Then enabling the stream of flue gas to communicate, between the upstream unit and the downstream unit with a stack opening to the atmosphere, and this outlet line is left open or partially open in nominal operation thereby equilibrating the pressure in the stream of flue gas to atmospheric pressure.

Apparatuses and methods for reforming of hydrocarbons including recovery of products. A reforming-zone effluent is separated into a net gas phase stream and a liquid phase hydrocarbon stream. The net gas phase stream may be passed separated into an H.sub.2 rich stream and a tail gas stream in a PSA. The tail gas may be passed through an absorber and then passed through a membrane to form a second H.sub.2 rich stream and a liquid stream. A second absorber is used to recover C.sub.3/C.sub.4 hydrocarbons. The two absorbers may be stacked on top of each other.