Consider the following materials: 1. Agricultural residues 2. Corn grain 3. Wastewater treatment sludge 4. Wood mill waste Which of the above can be used as feedstock for producing Sustainable Aviation Fuel?

1. A. 1 and 2 only
2. B. 3 and 4 only
3. C. 1, 2, 3 and 4
4. D. 1, 3 and 4 only

Answer: C

Explanation

Sustainable Aviation Fuel (SAF) is produced from various non-petroleum-based renewable feedstocks to reduce the carbon footprint of air travel. All the listed materials are recognized as potential feedstocks for SAF production: 1. Agricultural residues: Crop stalks, husks, and other plant waste from agriculture can be converted into SAF. 2. Corn grain: While its use for fuel is debated due to food security concerns, corn grain (and other oilseeds) can be processed into biofuels, including SAF. 3. Wastewater treatment sludge: This is a type of wet waste that can be utilized through processes like hydrothermal liquefaction to produce SAF. 4. Wood mill waste: Sawdust, wood chips, and other by-products from timber processing are significant biomass sources for SAF. Therefore, all four materials can be used as feedstocks for producing Sustainable Aviation Fuel. This topic is relevant to renewable energy, climate change mitigation, and sustainable development, frequently appearing in environmental current affairs.