Hydrocarbon generation and gasification study of Valia lignite, Gujrat, India

Abstract

ABSTRACT In the present investigation, an attempt was made on the Valia lignite, Surat, Gujarat, based on different analysis to determine the hydrocarbon generation, kerogen type, mineralogical characterization and CO2 gasification kinetics. Hydrocarbon generation is estimated by FTIR analysis and kerogen type have concluded by proximate and ultimate analyses data, SEM and EDX analysis were used to determine various mineral associated with coal. Isothermal CO2 gasification implemented by TGA at three different gasification temperature range of 900°C, 950°C, and 1000°C. Value of “A” (0.668) and “C” (0.502) factors concluded that the sample has the lowest aromaticity showed the highest hydrocarbon generation potential, which also validated by the Van Krevelen’s diagram. The results of FE-SEM and EDX of coal sample reveal several metals in various minerals form like sulfate, kaolinite, albite, mullite, Illite, hematite, hercynite, and pyrite. Alkali/alkaline earth metal oxides also found in ash. Kinetic parameters and activation energy of the sample were calculated by three kinetic models, such as the volumetric model (VM), grain model (GM), random pore model (RPM), and the Arrhenius equation. The CO2 gasification VM model showed a lower activation energy (E a ) value of 128.44 kJ/mol than the GM and RPM model value 130.31 kJ/mol and 133.98 kJ/mol, respectively, for the temperature range from 900°C, 950°C, and 1000°C. The overall study concludes that Valia lignite has sufficient potential for hydrocarbon generation and its suitability for clean coal technology such as CO2 gasification.