Design and optimisation of a small, robust outdoor duckweed bioreactor for operation under ‘on-site’ farmyard conditions

Simple item page
dc.contributor.advisorByrne, Edmond
dc.contributor.advisorKavousi, Fatemeh
dc.contributor.authorO'Sullivan, Grace
dc.contributor.funderDepartment of Agriculture, Food and the Marine, Ireland
dc.date.accessioned2025-01-31T15:03:02Z
dc.date.available2025-01-31T15:03:02Z
dc.date.issued2024
dc.date.submitted2024
dc.description.abstractDuckweed (Lemnaceae) is a small, aquatic plant that is ubiquitous across Ireland. It grows remarkably fast, with a doubling time of one to two days. Duckweed is typically found on slow moving water bodies, but it can grow on agricultural waste streams such as yard washings. Usefully, the plant removes excess nutrients (nitrogen and phosphorus) from wastewater to produce a high protein crop. Duckweed dry weight can contain up to 40% protein. Duckweed is currently being investigated for use in human nutrition, biofuel production, and the remediation of waste streams (Appenroth et al., 2017, Xu et al., 2012, Zhou et al., 2023). The rising need for sustainable agriculture systems magnifies the importance of a circular economy approach to farming. This project involves the design and optimisation of an outdoor duckweed growth system suitable for use on farms. It offers farmers a plausible solution to managing the large volumes of nutrient-rich wastewater produced on farms daily, whilst also generating high-value biomass. Hence, it can help provide a circular economy approach to sustainable agriculture. Currently, two main styles of growth systems are used in the production of duckweed: ponds and raceway systems. A literature survey (undertaken as part of this research) reveals that limited studies have been completed on the effect of system design on duckweed cultivation. The approach undertaken in this project involves a systematic analysis of fluid flow using Computational Fluid Dynamics (CFD) and tracer response experiments to inform the design of a system optimal for duckweed production. ANSYS Fluent is used to optimise the system geometry and interpret the effects of the geometry on nutrient distribution. Relative growth rate and nutrient uptake experiments were also employed to gain experiential knowledge and thus a holistic understanding of the impact of design on duckweed growth. From this study, it can be concluded that low levels of mixing within a cultivation system have a positive effect on both the relative growth rate of duckweed and its remediation ability. However, at higher flow rates the growth of duckweed is negatively impacted. The results also feature the design of a medium-scale outdoor duckweed cultivation system, informed by the literature review and experimental work. This work will inform stakeholders on the most suitable system for duckweed production in a farm setting. In addition to this, it will provide guidance on the style of system that is most suitable for large scale duckweed production sites worldwide.
dc.description.statusNot peer revieweden
dc.description.versionAccepted Versionen
dc.format.mimetypeapplication/pdfen
dc.identifier.citationO'Sullivanr, G. 2024. Design and optimisation of a small, robust outdoor duckweed bioreactor for operation under ‘on-site’ farmyard conditions . MRes Thesis, University College Cork.
dc.identifier.endpage99
dc.identifier.urihttps://hdl.handle.net/10468/16951
dc.language.isoenen
dc.publisherUniversity College Corken
dc.relation.projectDepartment of Agriculture, Food and the Marine, Ireland (The Duck-Feed project)
dc.relation.projectDuck-Feed
dc.rights© 2024, Grace O' Sullivan.
dc.rights.urihttps://creativecommons.org/licenses/by-nc-nd/4.0/
dc.subjectDuckweed
dc.subjectCircular economy
dc.subjectComputational fluid dynamics
dc.subjectBiorector design
dc.subjectFarmyard effluent
dc.subjectAnimal feed
dc.titleDesign and optimisation of a small, robust outdoor duckweed bioreactor for operation under ‘on-site’ farmyard conditions
dc.typeMasters thesis (Research)en
dc.type.qualificationlevelMastersen
dc.type.qualificationnameMRes - Master of Research
Files
Original bundle
Now showing 1 - 2 of 2
Thumbnail Image
Name:
OSullivanG_MEngSc2024.pdf
Size:
3.25 MB
Format:
Adobe Portable Document Format
Description:
Full Text E-thesis
Download
Thumbnail Image
Name:
OSullivanG_MEngSc2024_Submission for examination form.pdf
Size:
208.95 KB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
5.2 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Research Theses
College of Science, Engineering and Food Science - Masters by Research Theses
Environmental Research Institute - Masters by Research Theses
Process and Chemical Engineering - Masters by Research Theses