The Removal of Biomass Tar Derived Producer Gas by Means of Thermal and Catalytic Cracking Methods

Tar derived from biomass gasification system needs to be eliminated before applying biomass producer gas for avoiding equipment and its gas problems. In this study, thermal and catalytic cracking methods of biomass tar along with microwave assistance in heat transfer were experimented at various temperatures during 650-1,200 °C and residence at 0.24-0.5 s. The results present that high tar removal efficiency by approximately 90 % under thermal cracking treatment and about 98 % with catalytic cracking method. It also shows that the catalytic cracking especially modified catalyst could be lowered carbon deposition on catalyst surface.

AN EFFECT OF SPRAY CONFIGURATION AND ADSORBENT MATERIAL ON PERFORMANCE OF THE SPRAY SCRUBBER IN THE DOWNDRAFT GASIFIER-ENGINE SYSTEM

The work aims to investigate an effect of spray configuration and adsorbent material on performance of wet scrubber in removing tar gravimetric in producer gas. The scrubber is installed at small scale downdraft gasifier-engine system and the tests are conducted in two sections. Firstly, the scrubber is tested using water adsorbent at various spray flow configurations to the producer gas flow (cross flow, counter flow, mixed flow). Secondly, the scrubber is tested using adsorbent of cooking oil and waste of engine lubricant at cross flow spray configuration. The performance of the scrubber investigated are temperature profile, log mean temperature difference, heat transfer rate, and tar removal effectiveness. For spray configuration test, the result shows that cross spray configuration (CrS) has the optimum performance. The CsS scrubber has the highest LMTD, heat transfer rate, and tar removal efficiency among others. The values are 29.8°C, 7.84 kW, and 0.43, accordingly. Meanwhile, the test using different adsorbent indicates adsorption property of the adsorbent plays an important rules in tar removal effectiveness of the scrubber. The removal effectiveness of the scrubber for using adsorbent of water, cooking oil, and engine lubricant are 0.43, 0.12, and 0.60, respectively.

WOOD GASIFICATION. INFLUENCE OF PROCESS PARAMETERS ON THE TAR FORMATION AND GAS CLEANING

We present an analysis of influence of biomass pre-treatment and change of gasifying agent on the performance of an oxygen-steam-air updraft gasification plant and a technological process capable of delivering high quality producer gas. The results of these changes on composition of tar collected with absorption type gas purification unit, designed for dust and tar removal are also reported.