In order to reduce the CO2 emission of an existing 600MW(e) power plant in Hubei Province of China, a 30MW(th) biomass CFB gasifier was built to co-fire of the product gas in the pulverized coal boiler. Experiments were conducted with rice husks as the fuel. Different operation conditions, temperatures and loads, are investigated for their effects on the compositions, calorific properties, gasification efficiencies, carbon conversions and tar production. It was found that under the different working condition, the temperature curves along the riser height are similar, and temperatures at the bottom are higher than the top temperatures. The combustible components, calorific value and gasification efficiency of gas first increase and then decrease with temperature rise. The maximum calorific value and the maximum gasification efficiency of gas were 5751 kJ/Nm(3) and 73.41%, respectively, at 789 degrees Cand 814 degrees C. The gasification system runs smoothly under different loads, and the best gasification condition occurs at 30 MWth. (C) 2020 Elsevier Ltd. All rights reserved.