Table Contributions of emission sources

Table 4.
Contributions AR-C 66096 emission sources to life-cycle environmental impact potentials of bioethanol produced from sweet sorghum stem on saline–alkali land (%).GWPAPEPPCOPHTPFAETPMAETPTETPPlant cultivation unit79.8487.4692.9744.6470.8899.0964.7277.31 Nitrogen46.2122.707.1825.0660.401.1448.9671.17 Phosphorus3.060.7310.352.102.530.094.071.49 Potassium1.100.260.070.760.94/0.820.39 Pesticides1.420.250.664.776.020.2410.854.25 Irrigation0.480.370.063.210.07/// Diesel1.490.200.058.730.11/0.02/ Field emissions26.0762.9474.60/0.8297.59//Feedstock transport unit2.410.120.051.320.750.083.710.08Bioethanol conversion unit17.7512.426.9954.0428.370.8231.5722.61 Electricity13.3611.832.2136.208.770.258.6110.95 Auxiliary materials1.280.470.0712.400.000.5722.9611.66 Wastewater//4.64/8.47/// Biogas combustion3.120.110.075.4311.13///Full-size tableTable optionsView in workspaceDownload as CSV
The greenhouse gases (GHGs) considered are CO2, CH4, N2O, and CO. GWP was expressed using CO2 eq. The impact of specific GHGs was compared with that of CO2 over a 100-year period. In this study, CO2 emission from fertilizer production and soil N2O emission are the main sources of GWP during plant cultivation. Another important contributor is purchased electricity used in bioethanol conversion units.