Purification of Synthetic Gas from Fine Coal Waste Gasification as a Clean Fuel

The presence of CO2 in the syngas is attracting more attention in terms of reducing the greenhouse gas emissions in its utilisation. The aim of this study was to purify syngas from the CO2 content of fine coal gasification. Fine coal is gasified with and without absorption using CaO, which is hydrated to Ca(OH)(2) in the modified updraft gasifier at 450-700 degrees C. Apart from investigating the CO2 absorption process, the gasification process also evaluates the influence of temperature in terms of its synergy with Ca(OH)(2). The best conditions for the gasification process are achieved at 700 degrees C. The content of CO2 was proven to be well absorbed, which is characterised by a decrease in the CO2 content and an increase in H-2 in syngas. After the absorption process, the H-2 content obtained increased from 42.6 mole% to 48.8 mole% of H-2 at 700 degrees C. The H-2 ratio also increased after absorption to 2.57 from the previous value of 2.23. The highest absorption efficiency of CO2 by Ca(OH) 2 occurred at 700 degrees C at 50.63%. With an increase in temperature in the gasification process with absorption, the CO2 content decreased dramatically from 16.9 mole% to 3.9%. Ca(OH)(2) has good absorption power at CO2 at high temperatures.

Automated summary

This study aimed to purify syngas by absorbing CO2 using CaO, finding that the gasification process performed best at 700 degrees Celsius, resulting in a significant decrease in CO2 content and an increase in H-2. Ca(OH)2 demonstrated good absorption power for CO2 at high temperatures.