Shackley S.,University of Edinburgh |
Carter S.,University of Edinburgh |
Knowles T.,SME Renewable Energy Ltd. and 92K Russia Boulevard |
Middelink E.,SME Renewable Energy Ltd. and 92K Russia Boulevard |
And 2 more authors.
In part I we described the gasification technology and characterised the physio-chemical properties and environmental impacts of the rice husk char (RHC) by-product. In part II we present summary results from field trials using the RHC, and provide an estimate of the carbon abatement and economic evaluation of the system. Statistically significant yield increases are demonstrated for RHC addition in irrigated rice cultivation (33% increase in paddy rice yield for a 41.5t (dry weight) RHC application per hectare). The carbon abatement from the RHC addition is approximately 0.42tCO 2t -1 rice husk; including energy generation from gasification this increases to ca. 0.86tCO 2t -1. Assuming a carbon value of $5tCO 2t -1, and agronomic value of $3t -1 RHC based on the field trials, the economic value of the RHC varies from $9t -1 (including only recalcitrant carbon) to $15t -1 (including avoided emissions from energy production). We summarise results from parts I and II, concluding that the gasification-biochar system meets many of the criteria of sustainability, but requires better waste water management and more field trials to demonstrate repeatable agronomic efficacy of RHC application. © 2011. Source