(132a) Parametric Analysis of Membrane Properties on Post Combustion Flue Gas System Economics

Many different methods are required to address global decarbonization. While the transportation sector can rely on electrification and power generation can utilize renewable sources, the path to industrial decarbonization requires a more innovative approach¹. Industrial applications are more likely to need high heat sources and have long lived assets in the ground that are key to producing the chemical building blocks of our society. These applications, like cement, steel, and refractory materials, need low cost carbon capture systems to enable their decarbonization goals. Membranes have a unique modular nature and offer simplified, low cost, low energy systems that are a lynchpins for industrial decarbonization. When applied to post combustion flue gas, membranes can address hard to abate sectors like cement and steel² which are responsible for 15% of the global CO2 emissions.

This talk will discuss the carbon capture system design consideration for post combustion flue gas applications. The capital and operational costs are driven not only by the membrane sizing and costing, but also by the compressor costing and electricity use. System design optimization is paramount to determining best membrane staging design and balance of equipment³. To best understand this, Compact Membrane Systems(CMS) developed a model to investigate optimal staging designs. This talk will discuss the novel superstructure modelling approach used to enable membrane staging optimization for given membrane performances to find the lowest overall cost. To understand the tradeoffs, a parametric analysis was performed with membrane properties between 100-5000 GPU and 10-300 selectivity. Traditionally, higher selectivity allows for fewer stages to reach high purity products, and increased permeance, decreases the amount of membrane area needed for a given flow rate. Both are important to lowering the capital costs associated with the full system.

According to CMS’s analysis of compression cost, high performance at low pressure operation is a necessity for economic carbon capture (CC) with membrane systems. In the hard-to-abate CC applications studied, it was found that above a threshold selectivity, increased permeance unlocks significantly lower costs of capture but increased selectivity yields diminishing economic returns. Realistic capture costs were calculated with amortized installed capital estimates and industry relevant utility, maintenance, and labor cost estimates. Previous research has shown that membranes with low cost of manufacturing can be used with low pressure designs to provide low costs of capture^4,5. Because membranes with increased properties can be more expensive to manufacture, the implications of membrane costing were analyzed to determine the economic benefits of permeance and selectivity. According to these results, a high permeance membrane with modest selectivity (i.e., 1000 GPU and 20 CO₂/N₂ selectivity) can achieve capture costs under $50/ton with conservative costing assumptions. A high selectivity membrane with modest permeance (i.e., 200 GPU and 100 CO₂/N₂ selectivity) cannot achieve capture costs under $90/ton with the same costing assumptions.

1. Larsen, J. (2022, August 18). “A turning point for US climate progress: Assessing the climate and clean energy provisions in the Inflation Reduction Act.” Rhodium Group. Retrieved April 14, 2023, from https://rhg.com/research/climate-clean-energy-inflation-reduction-act/
2. Baker, Richard W., et al. "CO2 capture from cement plants and steel mills using membranes." Industrial & Engineering Chemistry Research57.47 (2018): 15963-15970.
3. Arias, Ana, et al. “Optimization of multi-stage membrane systems for CO₂capture from flue gas.” International Journal of Greenhouse Gas Control. 53 (2016). 371-390.
4. Han, Yang, Yutong Yang, and WS Winston Ho. "Recent progress in the engineering of polymeric membranes for CO2 capture from flue gas." Membranes10.11 (2020): 365.
5. Merkel, Tim, et al. Pilot testing of a membrane system for postcombustion CO2 capture. Membrane Technology And Research, Incorporated, Newark, CA (United States), 2015.