- Title
- Anaerobic process formulation for methane production during dry fermentation of Acacia Mearnsii (black wattle) feedstock
- Creator
- Tambro, Boniface Kangire
- Subject
- Anaerobic
- Subject
- Methane production
- Subject
- Fermentation -Acacia mearnsii
- Date Issued
- 2023-04
- Date
- 2023-04
- Type
- Master's theses
- Type
- Thesis
- Identifier
- http://hdl.handle.net/10948/66218
- Identifier
- vital:74443
- Description
- Various batch anaerobic digestion configurations and procedures, for the production of biogas using different feed-stock, have been undertaken in multiple studies. The research presented is set apart in its approach as it focuses on the use of black wattle leaves and cow dung mixture as feedstock to a micro plant facility creating biogas with a methane content of at least 50% during a short retention period of 30 to 35 days. Varying process parameters were applied to investigate the effect on methane production; the temperature control in a mesophilic range with a target temperature of 37°C, draining and drenching of inoculant as a means of heating reactors, and the effect of mixing mass ratio (black wattle leaves: cow manure) related to carbon and nitrogen were studied. A closed-loop batch anaerobic digester, based on the bio-methane potential principle, was used to conduct three individual experiments, each with two reactors. The carbon and nitrogen content of wet black wattle leaves, cow manure, and dam water were examined in triplicate. The average carbon content of wet black wattle leaves, cow manure, and dam water used during experimentation was found to be 6.75%, 27.84%, v and 1%, respectively with corresponding nitrogen content values of 0.57%, 1.44%, and 1%. The C: N ratio was 19.3:1 for wet black wattle, 11.84:1 for the cow manure, and 1:1 for the dam water with the total extracted solids in wet black wattle and cow manure were 46.32 % and 12.65 %. From the samples tested, the mixture of wet black wattle leaves and cow manure with a C: N ratio of 25:1 for the first reactor and 20:1 for the second reactor was used. Both mixtures had a pH of 6.3. Draining and drenching of reactors twice daily, by inoculation, kept the temperature in a mesophilic range, with 37°C as the optimal temperature to assess the production of methane from a mixture of black wattle leaves and cow manure, with temperature, pH, and C: N ratio kept constant. The results showed that the reactor with a C: N ratio of 25:1 and at an average temperature of 36.74°C produced 9170 ml of biogas within 35 days, of which 1094 ml was methane. The maximum methane production was during week 4 when 335 ml, or 25.81% of total biogas, was collected. Sufficient evidence exist that biogas production from a mixture of wet black wattle leaves and cow manure is feasible, but require further investigation to increase the yield.
- Description
- Thesis (MEng) -- Faculty of Engineering, the Built Environment, and information Technology, School of Engineering: Mechanical, 2023
- Format
- computer
- Format
- online resource
- Format
- Format
- 1 online resource (xviii, 111 pages)
- Publisher
- Nelson Mandela University
- Publisher
- Faculty of Engineering, the Built Environment, and information Technology
- Language
- English
- Rights
- Nelson Mandela University
- Rights
- All Rights Reserved
- Rights
- Open Access
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| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | SOURCE1 | Tambro, BK.pdf | 3 MB | Adobe Acrobat PDF | View Details Download |