The Evaluation of Carbon Emission from Waste Tires Pyrolysis Based on IPCC: A Case Study in Thailand

This research investigates the carbon emissions related to different waste tire management practices for processing an annual volume of 67,830 tons of waste tires. It emphasizes significant variations in the sources and amounts of emissions throughout pyrolysis, landfilling, and outdoor burning. Pyrolysis is a technique that transforms waste tires into multiple products. All items include syngas (9%), oil (40%), carbon black (32%), steel wire (13%), and sludge (6%). The process of pyrolysis consumes 1.9 MW of power and produces 9.9 MW of energy per year. This strategy is controlled and generally contributes to reduced CO2 emissions compared to burning waste outside. The net emissions, considering the advantages of energy consumption as well as material recovery, are estimated to be 0.17 – 0.18 x 105 tons CO2 eq./yr. Landfilling releases a small amount of CO2 since decomposition is slow. However, this process presents significant long-term environmental hazards related to the emission of methane, which is a potent greenhouse gas. The estimated emissions of methane are between 0.78 - 0.92 x 105 tons CO2 eq./yr. On the other hand, when tires are burned outside, a substantial amount of CO2 is released, that's about 1.69 - 1.86 x 105 tons CO2 eq./yr. This occurs because the carbon content of tires, which makes up 74 – 76% of their weight, undergoes oxidation during the burning process. Pyrolysis is a more sustainably beneficial approach compared to the others mentioned. It is especially beneficial since it allows for the recovery of energy. On the other hand, outdoor burning generates the maximum amount of CO2 emissions, and landfilling is concerned about long-term methane emissions.