Measuring the environmental impact of a carbon capture system integrated with a dehumidification system

Battery production is set to increase sixfold by 2030 compared to 2023. Dehumidification systems play a pivotal role in battery production, as multiple drying processes consume the majority of the energy required for manufacturing batteries. This thesis conducts a comparative cradle-to-grave Life Cycle Assessment (LCA) of two dehumidification systems. System 1 (S1) includes a standard dehumidification system, while System 2 (S2) combines a dehumidification system with a Direct Air Capture (DAC) system. Both systems are evaluated for use in a battery manufacturing plant in Poland. The environmental impacts of both systems throughout their lifecycle are compared, identifying the major contributing processes. The LCA adheres to the EU taxonomy, and utilizes the Recipe 2016 midpoint method for lifecycle environmental impact assessment. SimaPro software, utilizing the ecoinvent 3.0 database, was employed. The majority of the data, such as material usage in manufacturing and transportation within the product system, was sourced from the manufacturer. The functional unit for this study is defined as m³ of air conditioned, facilitating the comparison between S1 and S2. Selected impact categories include global warming, terrestrial ecotoxicity, marine ecotoxicity, human carcinogenic toxicity, human non-carcinogenic toxicity, and fossil resource scarcity. The study reveals that the usage phase contributes the most (92.4%- 99.9%) to the environmental impacts of S1 across all categories, with similar results for S2 (84.3%- 99.7%). S2, due to its DAC system, exhibits greater impacts in both the cradle-to-gate and cradleto-grave analyses. The environmental impacts from DAC of S2 heavily depend on the energy source (for regeneration of adsorbent) used during the usage phase. Due to Poland's reliance on fossil-based electricity, both systems exhibit significant environmental impacts. S2 only becomes carbon-negative when powered by a 100% renewable electricity grid, as in Paraguay, where the global warming indicator for cradle-to-grave results per functional unit shows negative environmental impact (-2.17E-04 kg CO2 eq.), indicating a carbon-negative system. Furthermore, comparing different carbon adsorbents during the cradle-to-gate phase revealed that activated carbon has a lower environmental impact than zeolite in all considered categories. After conducting the LCAs, it is recommended that inventory data be more refined, particularly the data from the secondary manufacturers. Developing countries should focus on policies that promote cleaner energy grids. As cleaner grids (Paraguay, Sweden) reduce the environmental impact of S2 significantly when compared to electricity grids of developing countries (India, China, Brazil). LCA should be conducted during the design phase of such systems to minimize environmental impacts, as the LCA results would pin point the most environmentally impacting processes (for example zeolite had significant impact in the cradle to gate phase of S2 other carbon adsorbents could have been considered). Lastly, the DAC unit could be redesigned to utilize a more renewable energy source for the regeneration of the adsorbent.