INTEGRATION OF CHLORELLA VULGARIS INTO PRODUCTION SYSTEMS: ENVIRONMENTAL AND TECHNOLOGICAL ASPECTS


  • O.H. Dombrovskiy MHP Eco Energy LLC
  • I.S. Traksler Institute of Engineering Thermophysics of the National Academy of Sciences of Ukraine
  • Ye.A. Derkach MHP Eco Energy LLC
  • A.V. Bondar MHP Eco Energy LLC
DOI: https://doi.org/10.31472/ttpe.3.2025.10
Keywords: Chlorella vulgaris, microalgae, biomethane, biogas, anaerobic digestion, photobioreactor.

Abstract

Objective: This study aims to explore the potential of Chlorella vulgaris as an efficient substrate for biomethanation, focusing on both liquid and dry biomass types. The research addresses the critical need for sustainable bioenergy sources and highlights the role of microalgae in bioenergy systems due to their high productivity, ability to capture CO₂, and compatibility with various bioprocesses.

Tasks:

  1. Cultivate Chlorella vulgaris in a photobioreactor under controlled environmental conditions to obtain liquid and dry biomass samples.
  2. Conduct detailed analysis of the physical and chemical properties of liquid and dry biomass, including moisture content, organic matter composition, and energy potential.
  3. Perform batch anaerobic digestion experiments in a mesophilic regime to evaluate biogas and methane production from both biomass types.
  4. Compare and analyze the differences in biogas yields, methane content, and overall energy efficiency between the liquid and dry biomass.
  5. Assess the broader implications of integrating Chlorella vulgaris into biomethanation systems in terms of environmental sustainability and resource efficiency.

Research Methods: The study employed a tubular photobioreactor (Algoliner PBR-100, Germany) for cultivating Chlorella vulgaris. Controlled parameters such as light intensity, temperature, and pH were maintained to ensure optimal growth conditions. Bold Basal Medium (BBM) was used as the cultivation medium. Biomass was harvested after a 21-day growth period and categorized into two types: liquid biomass (as-is) and dry biomass (dehydrated to a moisture content of 10-12%).

Batch anaerobic digestion tests were conducted at 37°C for 30 days, using a batch reactor system. Biogas production and methane content were measured daily, and cumulative biogas yields were calculated. Moisture content and volatile solids (VS) of the biomass were determined using standard gravimetric and biochemical methods.

Results:

  1. Moisture content analysis revealed a significant difference between liquid and dry biomass, with the latter being more concentrated in organic matter.
  2. Liquid biomass yielded approximately 430 L of biogas per kg of volatile solids, while dry biomass demonstrated a superior yield of 620 L per kg of volatile solids.
  3. Methane content in the biogas from dry biomass was higher (up to 60%) compared to the liquid form (55-58%), underscoring the enhanced efficiency of the dry substrate.
  4. The results highlight that Chlorella vulgaris biomass, especially in its dry form, is a viable and efficient substrate for biogas production.

Conclusion: The findings emphasize the potential of Chlorella vulgaris as a high-performance feedstock for biomethanation, capable of yielding substantial amounts of biogas and methane. The integration of microalgae into bioenergy systems offers multiple benefits, including the utilization of CO₂ emissions, waste valorization, and enhanced energy output. This study contributes to the broader adoption of algae-based bioenergy strategies and paves the way for further optimization of cultivation and digestion processes.

References

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Published
2025-09-30
How to Cite
Dombrovskiy, O., Traksler, I., Derkach, Y., & Bondar, A. (2025). INTEGRATION OF CHLORELLA VULGARIS INTO PRODUCTION SYSTEMS: ENVIRONMENTAL AND TECHNOLOGICAL ASPECTS. Thermophysics and Thermal Power Engineering, 47(3), 106-113. https://doi.org/https://doi.org/10.31472/ttpe.3.2025.10
Issue
Vol 47 No 3 (2025): Thermophysics and Thermal Power Engineering
Section
Articles

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