A Microalgae Photobioreactor System for Indoor Air Remediation: Empirical Examination of the CO2 Absorption Performance of Spirulina maxima in a NaHCO3-Reduced Medium

• Published in: Applied sciences Vol. 13; no. 24; p. 12991
• Main Authors: Han, Myungho, Park, Jinsuck, Kim, Inhan, Yi, Hwang
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-12-2023
• Subjects: Air pollution; Algae; Biomass; Carbon dioxide; Efficiency; Indoor air quality; Metabolism; microalgae; Outdoor air quality; photobioreactor; Pollutants; Respiration; Spirulina maxima; Ventilation; VOCs; Volatile organic compounds; United States > US
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app132412991

Microalgae-based photobioreactors (PBRs) have gained attention as a sustainable solution for indoor air quality (IAQ) control. This study investigates indoor CO2 absorption performance of Spirulina maxima (S. maxima) in NaHCO3-limited cultivation (standard: NaHCO3-free medium = 1:1 v/v%) of a lab-scale PBR system. Cultivation performance of three medium amendments (standard, 50% NaHCO3, and NaHCO3-free) was compared by observing cell growth for 30 days in a controlled environment. Empirical examinations were conducted to evaluate the algal CO2 uptake, and overall system performance in the culture volumes of 2, 4, and 7 L and natural indoor CO2 concentration of ~1100 ppm. We found CO2 was reduced by ~55%, in an air chamber of 0.064 m3, showing the greatest mitigation rate (~20%) on Day 4. Under a high concentration of CO2 (10,000 ppm), the CO2 levels were decreased up to ~90% before saturation. This research provides valuable insights into the development of S. maxima-activated IAQ control systems for airtight buildings.