Production of negative-emission biomethane by twin double-bed pressure swing adsorption with tail gas sequestration

Effect of combined primary and secondary amine loadings on the adsorption mechanism of CO2 and CH4 in biogas

“…MOFs, such as MIL-53 (Cr) and MOF-508b, have CH4 capacities of 0.4-0.5 mmol/g, with CO2 capacity of 1.2-1.6 mmol/g in equimolar CO2/CH4 breakthrough experiments at 100-200 kPa and 30°C [70,71]. A more recent study by Golmakani et al [7] on novel polymeric adsorbents, showed slightly higher CH4 adsorption of 0.12 mmol/g compared to the adsorbents presented here, with CO2 adsorption capacity of 0.6 mmol/g. Higher CH4 adsorption capacities result from the adsorbents presented here compared to low-moderate amine grafted SBA-15, which in this study show significantly lower CH4 adsorption of ~0.05 -0.06 mmol/g, at CO2 adsorption capacities that range from 0.68 to 1.11 mmol/g.…”

“…This qualifies biogas as a feasible source of energy towards the UK's net-zero target. Moreover, upgrading biogas to biomethane for an increased calorific value while producing a high-purity CO2 tail gas for storage can drive this initiative towards a negative-emissions energy source [7].…”

Advances, challenges, and perspectives of biogas cleaning, upgrading, and utilisation

“…However, the vacuum requirement in a 2 PVSA configuration increases the energy consumption. To address this additional energy penalty, Golmakani et al [362] developed a polymeric adsorbent with a practical working capacity achievable at above atmospheric pressure, and a cyclic performance that enables biogas upgrading by PSA without vacuum desorption required. They used a twin double-bed PSA unit to produce biomethane with a 91% recovery, and a CO2 tail gas purity >90% from the second PSA unit, thus suitable for geological storage.…”

A Review of Numerical Research on the Pressure Swing Adsorption Process

“…Aspen Adsorption™ is an industrially acclaimed software for multistep coupled process design and assessing feasibility-model development and simulation [47]. Considering the current computing power constraints, most process designs based on Aspen Adsorption™ adopted a 1D mathematic model with an adsorption-bed model and auxiliary-module models, which are summarized in Table 2 and Table 3, respectively [52][53][54][55][56][57]. However, the 1D model cannot describe the fine characteristics directly, such as the adsorber structure, adsorbent packed form and single particle internal morphology, nor their influence on the adsorption-mass transfer, resulting in the inability to accurately predict the local component concentration and other information in the adsorption process.…”