Effect of operational parameters and petroleum coke blending on the recycling of CO2 during fixed-bed gasification of bamboo char

Abstract

Biomass is a promising alternative energy source that can reduce our reliance on fossil fuels and achieving carbon neutrality. Gasification is a process of converting biomass into producer gas, which can be used to produce heat or electricity. The interaction between carbon-rich raw materials and catalysts in gasification is crucial for efficient conversion, product gas composition, and process stability. Understanding this interaction is essential for scaling up gasification processes and promoting sustainability and economic viability. The present study uses CO₂ as a gasification medium to address the recycling of CO₂ and its reduction to CO. This study focuses on three key operating parameters influencing gasification reactivity: catalyst, temperature, and pressure. Bamboo and petroleum coke are used as feedstock for gasification. Potassium carbonate salt is used as a catalyst for the reaction. It is found that using catalyst-impregnated biochar leads to higher concentrations of CO than un-impregnated biochar. A notable increase in CO production and char conversion was observed as the temperature increased from 1023 K to 1173 K at three different pressures. It is also observed that ash residues melted at a temperature of 1173 K, which impacted the char conversion. Petroleum coke is added to catalyst-loaded bamboo char to study the synergistic effect of alkali metal on the CO₂ gasification process. It is found that increasing the percentage of bamboo char in the blended samples led to a significant increase in both CO fraction and char conversion. These findings are useful for recycling of CO₂, and utilizing petcoke blended fuel samples in a gasification process.