Determinación de la huella de carbono del proceso de regeneración de catalizador agotado fcc usado en pirólisis catalítica de plásticos

Abstract

The implementation of the catalytic pyrolysis technique to face the problem related to overaccumulation of plastic waste requires the use of catalysts to improve the process; however, the regeneration of used catalysts is a complex procedure that emits polluting gases into the atmosphere; therefore, the aim of this research was to determine the carbon footprint in the regeneration process of used catalyst FCC (Fluidized Catalytic Cracking), useful in catalytic pyrolysis of plastics. The methodology used was research-based and the data were obtained from previous small-scale experiments; it started with the determination of two catalyst sample sizes, then the necessary equipment was selected for pretreatment, chemical treatment, thermal treatment and properly scaled ethanol recycling according to the sample size; then, the corresponding calculations were carried out to determine the energy consumption of each equipment, which was multiplied by the emission factor in order to obtain the individual carbon footprint and after the sum of these values, the global carbon footprint (CoF) of the process was obtained. After applying the methodology, it was determined that during the regeneration of 1713.88 kg/d of catalyst, a total energy consumption of 4350.92 kWh was reported, this originates an integral carbon footprint of 1996.79 kg CO2; while for the regeneration of polypropylene waste it is necessary to regenerate 325.25 kg of catalyst, a process that includes an overall energy consumption of 683.67 kWh allowing to establish a total HdC of 268.06 kg CO2. Thus, it is concluded that the catalyst regeneration process for the pyrolysis of plastics reflects a high HdC compared to mechanical recycling due to the high temperatures with which it works; however, this treatment allows the recovery of materials to produce added value products.