Degradation of biomass fuels during long term storage in indoor and outdoor environments

Graham, Shalini L. (2015) Degradation of biomass fuels during long term storage in indoor and outdoor environments. EngD thesis, University of Nottingham.

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This project has investigated the degradation of freshly harvested Willow chips, thermally treated wood pellets and white wood pellets in both indoor and outdoor storage.

Novel research has been carried out, by combining a range of fuels, storage scenarios, stockpile sizes and weather/seasonal patterns. A wide spectrum of tests was regularly performed on the stored fuel samples, to determine the extent of chemical, mechanical and biological degradation. The storage trials have been divided into Phase 1 and Phase 2, with Phase 1 starting in April 2011 and Phase 2 in November 2011.

The results showed that the extent of chemical degradation was not significant for the different fuels. The main concern for the Willow storage was the high concentration of different fungi on the chips and two pathogenic fungi were identified. In order to fully appreciate the deposition, inhalation and ingestion potential of fungal spores, the release mechanism of the spores from the wood fuels into the air would be recommended as future work.

The indoor white wood pellet pile stored in an open barn suffered severe mechanical degradation and it would be therefore advisable to store white wood pellets in a fully enclosed environment with no exposure to ambient temperature and humidity.

For the thermally treated pellets, the extent of degradation in the outdoor piles was far more significant than in the indoor one, with rainfall and humidity having an impact on the extent of degradation. Therefore, while the long term storage of thermally treated wood pellets in an open barn with covered storage would be a viable option; pellets stored in outdoor stockpiles would still be vulnerable to mechanical degradation. So outside storage of thermally treated pellets might be an option for short term strategic stocks, but in the majority of cases, covered storage would still be necessary.

Item Type: Thesis (University of Nottingham only) (EngD)
Supervisors: Eastwick, C.N.
Snape, C.E.
Quick, W.J.
Subjects: T Technology > TP Chemical technology
Faculties/Schools: UK Campuses > Faculty of Engineering
Item ID: 29110
Depositing User: Graham, Shalini
Date Deposited: 29 Sep 2015 12:42
Last Modified: 10 Sep 2016 01:10

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