You are encouraged to attend the defence. The details of the defence and attendance information is included below: 

Date: December 06, 2024
Time: 9:00 AM to 11:00 AM (PT) 

Defence mode:  Remote
Virtual Attendance: via Zoom

LINK TO JOIN: Please contact the Office of Graduate Administration for information regarding remote attendance for online defences.

To ensure the defence proceeds with no interruptions, please mute your audio and video on entry and do not inadvertently share your screen. The meeting will be locked to entry 5 minutes after it begins: please ensure you are on time.

Thesis entitled:  AGRICULTURAL WASTE MANAGEMENT THROUGH PYROLYSIS BASED ON POTATO ABOVE-GROUND BIOMASS

Abstract:  Agriculture's future could benefit from adopting sustainable models where residues become feedstock for thermochemical conversion systems, specifically through pyrolysis. This approach aligns with global efforts to transition away from first-generation biomass technologies, reducing competition between energy crops and food production, preventing land use change, and minimizing crop field emissions. This research investigates the potential of potato above-ground biomass as a representative herbaceous crop residue, focusing on biomass availability, Pine Wood Vinegar (WV) application for soil improvement and pesticide efficacy in potato cultivation, and biochar characterization. The study provides insights into sustainable management based on the early-to-mid maturing "Red Pontiac" potato cultivar.

Potatoes are a globally primary food source and an important greenhouse gas (GHG) emitter due to biomass decay and burning, highlighting the timeliness of this study. In phase 1, key metrics like days after planting (DAP), phenological stages based on the BBCH scale (“Biologische, Bundesanstalt, Bundessortenamt und Chemische Industrie”), and growing degree days (GDD) were used to characterize potato above-ground biomass, with water content reaching 89% at 100 DAP. In phase 2, three concentrations of WV were applied to foliage and soil, with 0.2% WV showing maximum herbicide efficacy (76% in B3), although effectiveness varied across blocks (p=4.95e^-06 ). WV was limited in preventing tuber scabs and had adverse effects at higher concentrations, causing leaf damage, while tuber yield differences across treatments were not statistically significant (p>0.05). Haulm killing was performed 15 days before tuber harvesting to optimize biomass recovery and tuber skin setting.

In phase 3, biomass was pretreated with water washing (W and UW) and subjected to pyrolysis at 400°C, 500°C, and 600°C for both leaves and stems. Fresh green material showed better pretreatment performance than dried samples, with significant ash removal only for leaves when compared to stems biochar (WL vs.WS and WL vs. UWS). Biochar yields ranged from 31% to 43%, influenced by pretreatment (prtr), plant section (psec), and temperature (temp), with significant interaction only for psec:temp (p=0.002). This study’s findings and methods provide a foundation for optimizing biomass utilization in agriculture, applicable to potato crops and other herbaceous residues.

Defence Committee: 
Chair: Dr. Matt Reid, University of Northern British Columbia
Supervisor: Dr. Jianbing Li, University of Northern British Columbia
Committee Member: Dr. Ron Thring, University of Northern British Columbia
Committee Member: Dr. Liang Chen, University of Northern British Columbia
External Examiner: Dr. Wenbo Zheng, University of Northern British Columbia