Application of food industry waste to agricultural soils mitigates green house gas emissions

Application of organic waste materials such as food processing and serving industry cooking oil waste (OFW) can recycle soil nitrate nitrogen (NO3–N), which is otherwise prone to leaching after the harvest of crop. Nitrogen (N) recycling will not only reduce the amount of N fertilizer application for corn crop production but is also expected to mitigate green house gas (GHG) emissions by saving energy to be used for the production of the same amount of industrial fertilizer N required for the growth of corn crop. Application of OFW at 10 Mg solid ha−1 y−1 conserved 68 kg N ha−1 y−1 which ultimately saved 134 L diesel ha−1 y−1, which would otherwise be used for the production of fertilizer N as urea. Average fossil energy substitution value (FESV) of N conserved/recycled was calculated to be 93 US$ ha−1 y−1, which is about 13 million US$y−1. Potential amount of GHG mitigation through the application of OFW to agricultural soils in Canada is estimated to be 57 Gg CO2Eq y−1.