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DOE OSTI · 2569124

Ammonium Looping with Membrane Absorber and Distributed Stripper for Enhanced Algae Growth

Liu, Kunlei [Univ. of Kentucky, Lexington, KY (United States)] (ORCID:0000000332290260)·Irvin, Bradley [Univ. of Kentucky, Lexington, KY (United States)]·Crocker, Mark [Univ. of Kentucky, Lexington, KY (United States)]
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Abstract

The objective of this project is to conduct a comprehensive investigation to develop and demonstrate a practical, reliable, and cost-effective integrated carbon dioxide (CO 2 ) capture and biofixation process for algae production. This process utilizes a chemical hindered ammonium solution (NH 4 OH) as both a capture reagent and an algae nutrient. The membrane absorber employed in the system ensured minimal ammonia (NH 3 ) emissions in the treated flue gas. Additionally, distributed solar-energy powered strippers located near the bioreactor modules facilitate solvent regeneration and enable just-in-time delivery of CO 2 and NH 3 to the algae, thereby minimizing the pH swing for enhanced productivity. The proposed membrane CO 2 absorber and solar-powered stripper is designed and seamlessly integrated with the existing 0.1 MWth bench-scale CO 2 capture system (CCS) and open raceway ponds (ORPs) at the University of Kentucky Center for Applied Energy (UK CAER) campus. The entire integrated process has undergone construction, operation, testing, and analysis. Furthermore, technology has been evaluated with a techno-economic analysis (TEA), technology gap analysis (TGA), life-cycle analysis (LCA), and a technology maturation plan (TMP). This project was performed within two budget periods, 54 months in duration. There are fourteen Project Tasks, twelve Milestones and four Success Criteria.

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Liu, Kunlei [Univ. of Kentucky, Lexington, KY (United States)] (ORCID:0000000332290260), Irvin, Bradley [Univ. of Kentucky, Lexington, KY (United States)], Crocker, Mark [Univ. of Kentucky, Lexington, KY (United States)]. 2025-06-01. Ammonium Looping with Membrane Absorber and Distributed Stripper for Enhanced Algae Growth. https://doi.org/10.2172/2569124

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