Title:
Energy Balance Analysis of Rice Straw for Anaerobic Digestion
Author(s):
Nguyen, V.H., Topno, S., Balingbing, C., Roeder, M., Quilty, J., Jamieson, C., Thornley, P., Gummert, M.
Document(s):
Paper
Abstract:
This study was conducted to evaluate the energy balances of rice straw supply chains and energy conversion through anaerobic digestion (AD). Rice straw supply chains included the operations of harvesting, collection, handling, transportation, and storage. Two supply chain options were considered - manual and mechanized operations. The biogas production was conducted in a small-scale anaerobic digester of 6 cubic meters. Input energy was accounted for direct and indirect energy. Direct energy included fuel consumption and manpower. Fuel consumption was measured directly for the vehicles and equipment relevant to the research processes. Manpower was obtained based on measuring labor time per ton of rice straw and the metabolic equivalent of task (MET). Indirect energy was calculated based on the energy for the manufacture, lubrication, and maintenance of the related machines and equipment. Results showed that total energy input of rice straw from harvesting to storage ranges from 593 to 1,133 MJ per ton (MJ t-1) of straw depending on the nature of operation (i.e., manual or mechanized). Input energy of rice straw AD with a 6 m3 digester made of high density polyethylene was about 4,000 MJ t-1 of straw. Net energy of rice straw supply chain and using it for generating biogas through AD was about 3,300 and 2,800 MJ t-1 of straw for the manual or mechanical supply chain, respectively. These practices of rice straw management can provide a benefit of output energy, which is 50% higher than the corresponding input energy.
Keywords:
anaerobic digestion, energy balance, rice straw, supply chain
Topic:
Biomass Policies, Markets and Sustainability
Subtopic:
Sustainability assessment and criteria
Event:
23rd European Biomass Conference and Exhibition
Session:
4AV.1.22
Pages:
1488 - 1491
ISBN:
978-88-89407-516
Paper DOI:
10.5071/23rdEUBCE2015-4AV.1.22
Price:
FREE
