Praxair Technology, Inc.

Timothy Mark Aaron

James Smolarek

Herbert Raymond Schaub

Minish Mahendra Shah

Frederick Wells Leavitt

Paul William Belanger

Richard John Jibb

Nicholas R Stuckert

Yang Luo

Michael John Sinicropi

Osemwengie Uyi Iyoha

John Harry Fassbaugh

Pedro Berges

Jeffrey Abbatiello

The invention relates to a process for modifying the VPSA/VSA/PSA cycle to allow for maximum product pressure without the need for a base load oxygen compressor (BLOC) or base load oxygen blower (BLOB), thus supplying low pressure oxygen (3 to 7 Psig) to the end user while at the same time lowering product costs 10 to 30%. The system of this invention preferably employs larger piping runs from the VPSA to the oxy-fuel control skids, larger piping for the oxy-fuel control skid, larger piping for the VPSA, low pressure drop flow measurements, and low pressure drop check valves.

Process for generating higher VPSA product pressure

An adsorbent bed structure and process is disclosed for use in an adsorption based gas separation process. A conventional adsorbent bed in a gas separation process is replaced with a one or more modular compact adsorbent bed units which are connected to make an adsorbent bed structure. The modular design requires lower fabrication and maintenance costs; is easier to transport; and is easier to load with adsorbent material.

Adsorption bed structure and process

A catalytic reactor is provided with one or more reaction zones each formed of set(s) of reaction tubes containing a catalyst to promote chemical reaction within a feed stream. The reaction tubes are of helical configuration and are arranged in a substantially coaxial relationship to form a coil-like structure. Heat exchangers and steam generators can be formed by similar tube arrangements. In such manner, the reaction zone(s) and hence, the reactor is compact and the pressure drop through components is minimized. The resultant compact form has improved heat transfer characteristics and is far easier to thermally insulate than prior art compact reactor designs. Various chemical reactions are contemplated within such coil-like structures such that as steam methane reforming followed by water-gas shift. The coil-like structures can be housed within annular chambers of a cylindrical housing that also provide flow paths for various heat exchange fluids to heat and cool components.

Catalytic reactor

A pressure swing adsorption process for the recovery of oxygen from air improves upon a prior art process by depressurizing the adsorbent bed within an adsorbent vessel to an intermediate pressure by releasing void space gas from the product end of the vessel to a low purity oxygen tank while concurrently evacuating the adsorbent vessel from the feed end. This action enables an increased speed of depressurization and a reduction of the cycle time. Further, the adsorbent bed is repressurized to an intermediate pressure from the product outlet end with gas from the low purity oxygen tank, while concurrently pressurizing the adsorbent vessel from the input feed end. This action increases the load time fraction for a feed/vacuum blower. Further, oxygen is introduced to the product end of the adsorbent bed vessel from a high purity oxygen tank (which provides product to downstream applications) while concurrently, air is introduced to the feed end of the adsorbent bed within the vessel. This enables an increased speed of increase in pressure in the bed from the intermediate desorption pressure. Next, a reduction in pressure ratio during the cycle elevates the pressure within the desorption vessel to approximately 7 psia, thereby reducing the evacuation requirements placed on the feed/vacuum blower. The above actions enable achievement of efficiency improvements on the order of 10%.

Single bed pressure swing adsorption process for recovery of oxygen from

Waste heat generated within a pressure swing adsorption system is effectively captured and utilized to preheat the feed gas passing to a feed gas blower for compression to the desired adsorption pressure level. The energy efficiency of the system, and overall system performance, are thereby enhanced.

Pressure swing adsorption heat recovery

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East Amherst, NY, United States of America

Timothy Mark Aaron