Design and Implementation of Direct Air Capture Systems Based on Moisture Swing Adsorption for Efficient Carbon Dioxide Removal

Direct air capture (dac) is necessary for achieving negative emissions and meeting the temperature targets outlined in the paris agreement. However, challenges of scalability and energy demands persist. This paper presents a comprehensive design framework for large-scale dac systems utilizing moisture swing adsorption (msa), an innovative method that leverages humidity cycles to regenerate sorbents with near-isothermal energy, thereby reducing energy penalties by 50-70% compared to thermal swing alternatives. The study proposes an architecture combining modular air contractors, structured sorbent monoliths using anion exchange resins, co2 compression trains, and controlled humidification chambers, enabling continuous cyclic operation in various climatic conditions. Governing equations for momentum balance, mass transfer, and adsorption kinetics inform finite element simulations and computational fluid dynamics, which are validated against laboratory-scale experimental data. Key findings reveal 1.2-1.8 mmol co2/g working capacities with 1-5 t h2o/t co2 and levelized costs of $150-300/t co2 at current scales, which are projected to decline to $8- 150/t with deployment learning. The framework addresses critical scale-up considerations, including environmental variability, material durability, and infrastructure integration. In practice, msa-dac is positioned as a viable negative emissions technology (net) for integrating renewable energy, modular deployment, and carbon utilization, supporting global decarbonization objectives.