Simulasi Termodinamika Perengkahan Tar pada Keluaran Fixed Bed Gasifier

Abstract

Gasification is process to convert solid fuel such as biomass to gaseous fuel. Gasification produces synthetic gas which can be used as fuel, or feedstock for chemical synthesis. Tar production is one of major problem in gasification. Tar can be reduced by steam reforming of producer gas and modification of gasifier’s configuration. Gasifier and tar catalytic cracking reactor configurations and operating conditions are studied by using equilibrium thermodynamic model for steam reforming process. Steam/tar mole ratio and operation temperature must be taken into consideration to minimize tar production and prevent coke formation in catalyst. Simulation result can give guidance about operating condition of steam tar cracking reactor and guidance for gasifier configuration to minimize tar production. Simulation results showed that in order to eliminate tar and prevent coke formation, tar cracking reactor minimum temperature of 500-700oC should be used for downdraft gasifier, 662-756oC for conventional updraft gasifier, and 648-715oC for modified downdraft gasifier depending on steam/tar ratio in tar cracking reactor feed.