Efficient Cycle Recovery of Hydrogen from a Low Concentration Pyrolysis Gas Stream by Pressure Swing Adsorption – An Experimental Evaluation

Based on pressure swing adsorption, Proportion Pressure Swing Adsorption (PPSA), a new enrichment method with high safety, was suggested to enrich the low concentration coal bed gas. A mixture of active carbon (CA) and carbon molecular sieve (CMS) was employed as adsorbent in the process of PPSA. The methane and oxygen in coal bed gas were adsorbed simultaneously. The experimental study was carried out in order to verify the feasibility of this method. The equilibrium adsorption characteristic of CA and CMS were tested. The results showed that both concentrations of CH4 and O2 in desorption gas could be controlled well and would not exceed the explosion limit in enrichment process by adjusting the mass ratio of CMS5/AC1. Therefore, the new method, PPSA, can guarantee the safety in enrichment of coal bed methane.

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Safe Separation of the Low-Concentration and Oxygen-Bearing Coal Mine Methane by Vacuum Pressure Swing Adsorption

Adsorption Science & Technology ◽

10.1260/0263-6174.32.8.667 ◽

2014 ◽

Vol 32 (8) ◽

pp. 667-679 ◽

Cited By ~ 3

Author(s):

Xiong Yang ◽

Yingshu Liu ◽

Yongling Li ◽

Yu Meng ◽

Chuanzhao Zhang ◽

...

Keyword(s):

Coal Mine ◽

Pressure Swing Adsorption ◽

Vacuum Pressure ◽

Low Concentration ◽

Coal Mine Methane ◽

Vacuum Pressure Swing Adsorption ◽

Pressure Swing

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Impact of Process Parameters on Oxygen-Bearing Low Concentration Coal Mine Methane Enrichment by Proportion Pressure Swing Adsorption

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.549.961 ◽

2012 ◽

Vol 549 ◽

pp. 961-965

Author(s):

Yong Ling Li ◽

Ying Shu Liu ◽

Xiong Yang ◽

Yu Meng ◽

Chuan Zhao Zhang

Keyword(s):

Oxygen Concentration ◽

Coal Mine ◽

Molecular Sieves ◽

Pressure Swing Adsorption ◽

Methane Concentration ◽

Exhaust Gas ◽

Adsorption Time ◽

Low Concentration ◽

Coal Mine Methane ◽

Pressure Swing

Conventional PSA methods with a single adsorbent can result in an explosive CH4 concentration of 5 to 15%, making low concentration coal mine methane (LCCMM) or risky in terms of safety at a concentration of 30%. Proportion Pressure Swing Adsorption (PPSA) is a new and safer enrichment method suggested for LCCMM enrichment that uses a mixture of active carbon (AC) and carbon molecular sieves (CMS) as adsorbents. The effect of adsorption Pressure, adsorption time and bed length on the PPSA process were investigated to verify the feasibility of this method. The experiment results show that the methane concentration in desorption gas and the oxygen concentration in exhaust gas increased and decreased, respectively, with an increase in adsorption pressure or bed length. And the methane concentration in desorption gas is increased with the adsorption time expanding, but the recovery of methane is reduced. So the methane concentration in desorption gas can be increased to more than 30% and the oxygen concentration in exhaust gas be decrease to less than 12% by increasing the adsorption pressure or lengthening the bed.

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Adsorbents for Oxygen-Bearing Low Concentration Coal Mine Methane Enrichment by Proportion Pressure Swing Adsorption

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.479-481.521 ◽

2012 ◽

Vol 479-481 ◽

pp. 521-524

Author(s):

Yong Ling Li ◽

Ying Shu Liu ◽

Xiong Yang

Keyword(s):

Coal Mine ◽

Pressure Swing Adsorption ◽

Methane Concentration ◽

Enrichment Method ◽

Adsorption Characteristic ◽

Low Concentration ◽

Coal Mine Methane ◽

Explosion Limit ◽

Pressure Swing ◽

Explosion Risk

Traditional Pressure Swing Adsorption (PSA) approach of using single adsorbent probably makes methane concentration very close to the explosion limit and may result in explosion risk in the adsorption process, when methane concentration in coal min methane is blow 30%. Based on pressure swing adsorption, Proportion Pressure Swing Adsorption (PPSA), a new enrichment method with high safety, was suggested to enrich low concentration Coal mine methane (LCCMM). A mixture of active carbon (AC) and carbon molecular sieve (CMS) was employed as adsorbent in the process of PPSA. The methane and oxygen in CMM were adsorbed simultaneously. The experimental study was carried out in order to verify the feasibility of this method. The equilibrium adsorption characteristic of AC and CMS were tested, the mixture of AC1 and CMS5 are chosen as adsorbents for LCCMM enrichment by PPSA.

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