The rate of recovery of a purification target gas from a gas purification apparatus that uses a PSA device is improved, and both a high purity and a high recovery rate are achieved with good power efficiency. The present invention is directed to a gas purification method using the PSA method, in which a carbon molecular sieve having a pore volume, at a pore diameter of 0.38 nm or more, of not exceeding 0.05 cm.sup.3/g and a pore volume, at a pore diameter of 0.34 nm, of 0.15 cm.sup.3/g or more, in a pore diameter distribution measured by the MP method is used as an adsorbent, and, in an adsorption step, a miscellaneous gas is adsorbed from a source gas by bringing the source gas into contact with the adsorbent for 10 seconds or more and 6000 seconds or less so as to obtain a concentrated methane.

The present invention relates to a process for purification of a carbon dioxide feedstock, for example from a production well, which comprises carbon dioxide and gaseous and liquid C.sub.1+ hydrocarbons. Specifically, a carbon dioxide feedstream is passed through one or more separation unit wherein each separation unit removes one or more C.sub.1+ hydrocarbon from the carbon dioxide feedstream to provide a richer carbon dioxide gas stream. The process comprises one or more separation unit which employs an adsorption media and has an adsorption step and a media regeneration step wherein the regeneration step may be operated as a batch process, a semi-continuous process, or a continuous process. One embodiment of this method provides for the use of a different regenerable adsorbent media in two or more separation units.

The present invention discloses a dust removing and coding method for an active coke regeneration apparatus. When the active coke regeneration apparatus is operating, the method includes the following: generating two negative pressure regions respectively at a discharge end and a feeding end; sucking out leaked vapor and dust by means of the negative regions; and cooling down the active coke regeneration apparatus by using gas flow generated by the negative pressure. Moreover, the present invention provides a device for implementing the method as described above.

Industrial waste derived adsorbents were obtained by pyrolysis of sewage sludge, metal sludge, waste oil sludge and tobacco waste in some combination. The materials were used as media to remove hydrogen sulfide at room temperature in the presence of moisture. The initial and exhausted adsorbents after the breakthrough tests were characterized using sorption of nitrogen, thermal analysis, XRD, ICP, and surface pH measurements. Mixing tobacco and sludges result in a strong synergy enhancing the catalytic properties of adsorbents. During pyrolysis new mineral phases are formed as a result of solid state reaction between the components of the sludges. High temperature of pyrolysis is beneficial for the adsorbents due to the enhanced activation of carbonaceous phase and chemical stabilization of inorganic phase. Samples obtained at low temperature are sensitive to water, which deactivates their catalytic centers.

A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

An activated carbon absorber, in particular an activated carbon absorber for use by a user of an externally ventilated breathing mask or breathing hood. The activated carbon absorber includes a housing for accommodating a filter cartridge, and the housing has the following features: an air inlet supply port to receive compressed air from an air-supply unit; a connector for connecting to a breathing mask or hood; a unit which can be fastened to the body of or to or on the housing of the activated carbon absorber and which is capable of forming a detachable connection with another component in particular a sliding or slip connection.

A method of using a nanoporous carbon material for adsorption of one or more PAH and diesel fuel from an aqueous solution is described. The aqueous solution may comprise the one or more PAH at a concentration of 0.1 mg/L-1 g/L, and the diesel fuel at a concentration of 0.1-5 g/L. The nanoporous carbon material may adsorb at least 96 wt % of one or more PAH within 10 minutes. The nanoporous carbon material may be obtained by contacting a carbonized asphalt with a base.

Methods for desorbing volatile organic compounds (VOCs) from beaded activated carbon (BAC) that is loaded with VOCs, during the VOC abatement process using the fluidized carbon bead system include transferring the loaded BAC in an adsorber to a desorber, where a stream of organic solvent passes over the BAC to dissolve at least a portion of the adsorbed VOCs into the organic solvent to regenerate BAC. The regenerated BAC is returned to the adsorber. The organic solvent containing dissolved VOCs may be transferred to a distiller to separate the organic solvents from the dissolved VOCs and may be reused as the organic solvent in the desorber.

The present inventors have developed systems and processes for reducing the overall carbon consumption needed for the generation of low COD treated water. In certain aspects, the systems and processes described herein include an oxidation stage (e.g., one that utilizes ozone, hydrogen peroxide, ultraviolet, or a combination thereof for oxidation) between a first activated carbon stage and a second activated carbon stage to reduce a total carbon consumption within the associated system or process.

A system and method for producing a modified coal ash involves collecting a bulk quantity of such coal ash, generally after it has been produced or landfilled, or is otherwise at temperatures closer to ambient, as opposed to power plant operational temperatures. In one possible implementation, the method herein involves removing carbon from the coal ash, such removal occurring by exposing the carbon to indirect heat, that is, externally-applied heat. For coal ashes with higher ash content. This removal is accomplished by subjecting the coal ash stream to heat, in one implementation, ranging between 850° F. and 1200° F., and such heat exposure occurring from about 10 minutes to about 30 minutes. The range of exposure time for the coal ash is determined so as to reduce the LOI from its initial level to a level acceptable for intended re-use or recycling. In one application, the LOI of carbon in the ash is reduced to 3% or less carbon. Upon completion of the range of the exposure time, the coal ash stream is removed from the sublimation heat, thereby forming a modified coal ash.