Msc: Sustainable Engineering : Chemical and Process Engineering
Conclusion
Anaerobic digestion presents Scotland a multi-faceted solution that simultaneously addresses waste management, renewable energy generation, and sustainable agriculture. With ongoing technological advancements, supportive policies, and public education, AD has the potential to reshape Scotland's energy landscape and secure a cleaner, greener future for generations to come.
This work demonstrates the feasibility of producing biomethane from cow manure at a rate of 23,400 kg/day. Using Aspen Plus simulations, we calculated potential biogas yields and methane content, ultimately designing a viable anaerobic digestion (AD) system. The Coolfarmtool analysis highlights the potential of this AD system to significantly reduce greenhouse gas (GHG) emissions compared to conventional manure management practices.
Our findings underscore the following:
• Biomethane Production Potential: The designed AD system with a ratio of 95:5 manure with distillery can produce 30 kg/h of biomethane with a purity of 93% meeting the infection grid criteria. This demonstrates the potential to convert agricultural waste into a valuable renewable energy source.
• Environmental Benefits: The assessment using the Coolfarmtool indicates a significant reduction in GHG emissions achievable through biomethane production. AD with biomethane upgrading captures 504 tons CO2 yearly (equal to emissions from 315 cars). This highlights how AD contributes to sustainable agricultural practices and the mitigation of climate change.
In summary, our findings provide a strong foundation for considering biomethane production from cow manure and distillery waste as a viable strategy for waste valorisation, renewable energy production, and the reduction of GHG emissions.
Limitations and Future work
Data availability: Accessing real-time operating data, yield information, and economic details from commercial AD plants might be restricted due to commercial confidentiality.
Lack of references available: Lack of information about the feedstock composition in Scotland.
Software Expertise/Time constraints
Economic Analysis: While this work verifies technical feasibility, further economic analysis is crucial to determine the commercial viability of this biomethane production project.
Digestate Management: The AD process generates digestate, a nutrient-rich byproduct. Exploring sustainable management and utilization of the digestate is important for maximizing the benefits of this system
Acknowlegments
Dear Dr Sorcha Daly, Dr Tuohy, classmates, and everyone involved,
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We, the AD group, would like to express our sincere gratitude for your invaluable support throughout this project journey.
Prof Sorcha , your unwavering patience, guidance, and willingness to help whenever we needed it have been instrumental to our success. We truly appreciate your dedication and the expertise you shared with us.
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Professor Tuohy, thank you for your insightful orientation, your constructive feedback during our sessions, and your continuous support throughout the project. Your guidance has been invaluable in shaping our understanding and approach.
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To our classmates and everyone else who contributed directly or indirectly, thank you for your collaboration, ideas, and encouragement. Your collective efforts have made this project a truly enriching experience.
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We are deeply grateful for the opportunity to have worked alongside such a talented and supportive team. Thank you all for making this journey a memorable one.
Sincerely,
The AD group