Abstract: In order to verify the feasibility of ligniteblended burning in the 300MW unit of the Heilongjiang Huadian Qiqihaer Thermal Power Company Limited, the maximum ratio of the lignite in the ligniteblended burning was determined, which can ensure the safe and stable operation under the rated load. In the 1025t/h boiler, the bituminite and the lignite are pulverized separately, and blended and burned in furnace through different burners. The experiments of the pulverizing system output, the characteristics of the coal and the boiler efficiency in different ligniteblended burning mode were carried out. The experiment result shows that the maximum ratio of the lignite in the ligniteblended burning is about 54%, and in this condition, the main operation parameters of the unit are normal, and there was no serious slagging even at full load. Under the same load, the boiler efficiency of ligniteblended burning is decreased slightly. Considering the difference between the lignite and the bituminite prices, the cost of the unit with ligniteblended burning is decreased greatly, and the economical benefit of the unit increased obviously.

Key words: lignite-blended burning, parameters of equipment, characteristics of coal quality, test data, economical analysis, estimation