Indonesian brown-coal with high ash-content is gasified by two microwave steam-plasmas heating up the gas temperature in a reaction chamber of 1145 l in a swirl-type gasifier for production of hydrogen-rich synthetic gas. With additional heating of synthetic gas by a partial oxidation of coal, the inner temperature of the gasifier can reach to 1700 degrees C. The carbon conversion rate at the chamber temperature of 1640 degrees C is almost 100 percent, ensuring a complete gasification of carbons in a low-grade coal. The cold gas efficiency of the hydrogen-rich synthetic gas is 84%, very high in a relatively-small gasifier like the experiment here. The total calorific value of the synthetic gas is 500 kW. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.