A multi-stage process to remove contaminant gases from raw methane streams is provided. The present technology is an innovative solution to recover and purify biogas by use of a process having at least two pressure swing adsorption stages. Taking advantage of the presence of carbon dioxide in the raw biogas streams, nitrogen and oxygen are bulky removed in the first stage, using selective adsorbents, and a nitrogen and oxygen-depleted intermediate stream is yielded to the second stage. The second stage employs an adsorbent or adsorbents to selectively remove carbon dioxide and trace amounts of remaining nitrogen and oxygen, thus producing a purer methane stream that meets pipeline and natural gas specifications.

The present invention is directed to a method and system of purifying hydrogen supplied from a storage cavern, particularly to removing methane and other hydrocarbons from the hydrogen withdrawn from the cavern by using selective adsorption. The adsorbed impurities can be removed from the adsorbent by increasing the temperature, reducing the pressure, or a combination of both.

The present invention is directed to a method and system of purifying hydrogen supplied from a storage cavern, particularly to removing methane and other hydrocarbons from the hydrogen withdrawn from the cavern by using selective adsorption. The adsorbed impurities can be removed from the adsorbent by increasing the temperature, reducing the pressure, or a combination of both.

A radial flow adsorption vessel comprising a cylindrical outer shell having a top end and a bottom end, the top end is enclosed by a vessel head that provides a centrical opening usable as a port to introduce or remove adsorbent particles into or from the vessel; at least one annular adsorption space disposed inside the shell, the at least one annular adsorption space defined by an outer and inner cylindrical porous wall, both co-axially disposed inside the shell; and a loading device for the adsorbent particles positioned above the at least one annular adsorption space at the top end of the vessel, the loading device comprises at least one conical element that extends radially to the outer cylindrical porous wall, the at least one conical element provides a plurality of orifices arranged at least in a region sitting above the at least one annular adsorption space.

An evaporated fuel treatment device includes a main adsorption chamber and a sub adsorption chamber. The sub adsorption chamber includes a first adsorption layer, a second adsorption layer and a high-desorption layer. The second adsorption layer is situated closer to an atmosphere port than the first adsorption layer is, and has a lower performance of adsorbing fuel vapor than the first adsorption layer does. The high-desorption layer is situated closer to the main adsorption chamber than the first adsorption layer is, and a higher performance of desorbing the fuel vapor than the first adsorption layer or the second adsorption layer does.

The present disclosure describes an evaporative emission control canister system that includes: one or more canisters comprising at least one vent-side particulate adsorbent volume comprising a particulate adsorbent having microscopic pores with a diameter of less than about 100 nm; macroscopic pores having a diameter of about 100 - 100,000 nm; and a ratio of a volume of the macroscopic pores to a volume of the microscopic pores that is greater than about 150%, and having a retentivity of about 1.0 g/dL or less. The system may further include a high butane working capacity adsorbent. The disclosure also describes a method for reducing emissions in an evaporative emission control system.

An evaporative emission control canister system comprises an initial adsorbent volume having an effective incremental adsorption capacity at 25° C. of greater than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, and at least one subsequent adsorbent volume having an effective incremental adsorption capacity at 25° C. of less than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, an effective butane working capacity (BWC) of less than 3 g/dL, and a g-total BWC of between 2 grams and 6 grams. The evaporative emission control canister system has a two-day diurnal breathing loss (DBL) emissions of no more than 20 mg at no more than 210 liters of purge applied after the 40 g/hr butane loading step.

Disclosed herein is an air cleaner which performs dust collection and sterilization as well as deodorization while having a small size enough to be fitted into a vehicle cup holder for its use, and has a strong and easy maintenance structure. The air cleaner includes a photocatalytic UV LED (57) installed on an UV LED substrate (55), and a photocatalytic filter installed on a surface facing the photocatalytic UV LED while being spaced apart from the UV LED substrate. The photocatalytic filter has a structure in which a photocatalytic material is coated on a base in which a plurality of cells (83) defining an air flow path in a direction toward the photocatalytic UV LED are arranged in parallel adjacent to each other.

An evaporative emission control canister system comprises an initial adsorbent volume having an effective incremental adsorption capacity at 25° C. of greater than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, and at least one subsequent adsorbent volume having an effective incremental adsorption capacity at 25° C. of less than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, an effective butane working capacity (BWC) of less than 3 g/dL, and a g-total BWC of between 2 grams and 6 grams. The evaporative emission control canister system has a two-day diurnal breathing loss (DBL) emissions of no more than 20 mg at no more than 210 liters of purge applied after the 40 g/hr butane loading step.

A compressed air supply unit for operating a pneumatic unit by means of a compressed air flow, in particular of an air suspension unit of a vehicle, comprises an air dryer arrangement in a main pneumatic line that pneumatically links a compressed air feed line from an air compressor and a compressed air connection to the pneumatic unit. A valve arrangement is pneumatically connected to the main pneumatic line for controlling the compressed air flow. The air dryer arrangement has a drying container having a container outer wall. A partition along a length of the drying container divides an internal space delimited by the container outer wall into first and second chambers delimited by the partition and the container outer wall. The partition adjoins the container outer wall along the length of the drying container, and the first and second chambers are adjacent to one another along that length.