Pressure swing adsorption reformer

Fig. 2. Hydrogen production flow sheet showing steam reforming, shift, and pressure swing adsorption (PSA). BFW = boiling feed water.

Hydrogen Liquefaction. Hydrogen can be produced from caustic—chlorine electrolytic cells, by decomposition of ammonia or methanol, or by steam—methane reforming. Hydrogen recovered by these methods must be further purified prior to Hquefaction. This is generally achieved by utilizing pressure swing adsorption methods whereby impurities are adsorbed on a soHd adsorbent. 

Figure 4.1. A process for producing hydrogen by steam reforming of hydrocarbons (1) reforming furnace (2,3) purification section, (4) shift converter, (5) pressure swing adsorption.

SMR—steam methane reformer ATR—auto thermal reformer POX—partial oxidation PSA—pressure swing adsorption... 

In most hydrogen plants, a pressure-swing adsorption (PSA) system is used for hydrogen purification. In these plants, a major portion of reformer fuel is PSA offgas with a hydrocarbon stream for makeup fuel. 

Because of the modular nature of fuel cells, they are attractive for use in small portable units, ranging in size from 5 W or smaller to 100 W power levels. Examples of uses include the Ballard fuel cell, demonstrating 20 hour operation of a portable power unit (32), and an IFC military backpack. There has also been technology transfer from fuel cell system components. The best example is a joint IFC and Praxair, Inc., venture to develop a unit that converts natural gas to 99.999% pure hydrogen based on using fuel cell reformer technology and pressure swing adsorption process. 

Steam methane reforming 93 Pressure-swing adsorptive reactor (PSAR)... 

The advanced reformer unit combines naturally with a Pressure Swing Adsorption (PSA) system to permit supply of complete hydrogen facilities totally skid mounted and factory assembled with up to 6 million scf/day capacity in a single reformer train. 

Description The generic flowsheet consists of feed pre-treatment, prereforming (optional), steam-HC reforming, shift conversion and hydrogen purification by pressure swing adsorption (PSA). However, it is often tailored to satisfy specific requirements. 

In some ammonia process schemes operating without a secondary reformer and applying pressure swing adsorption (PSA) for further purification (KTI PARC), only a HTS is used. 

The heat in the exit gas is recovered downstream the tubular reformer, usually by the production of steam, preheating of boiler feed water, etc. The final separation into the desired product compositions depends on the application. Pressure swing adsorption (PSA) is in most cases used if pure hydrogen is desired. Pure carbon monoxide can be obtained by cryogenic separation in a cold box. Adjustment of the H2/CO ratio can be accomplished by polymer membrane modules with different selectivities for permeation of the two compounds. 

Develop an efficient, cost-effective means to purify the hydrogen-rich reformate to pure hydrogen employing pressure swing adsorption (PSA) technology ... 

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