PURPOSE: To enable a combustion of fine powder coals at less energy cost to be performed by a method wherein each of auxiliary combustion gas containing concentration of oxygen of more than a specified value and fine powder coals are preheated to a specified temperature and the fine powder coals are ignited with the auxiliary combustion gas.

CONSTITUTION: In a burner for an electric furnace for melting scraps and a melting furnace for aluminum and copper etc.,when an auxiliary combustion gas and fine powder coals are preheated and the fine powder coals are ignited with the auxiliary combustion gas, if T = auxiliary combustion gas temperature (°C), C = concentration of oxygen in the auxiliary combustion gas (%) and t = temperature of fine powder coals (°C), an equation of T≥ exp{14.14-1.84lnC-exp(0.01127t-3.444)}, where t≤300°C and C≥30%, a combustion is carried out to fulfill this condition. When the fine powder coals are preheated to above 300°C, low temperature tar is extracted and a feeding or transportation of fine powder coals becomes difficult. When the combustion is performed with an exclusive fine powder coal burner in a range of a preheating temperature of fine powder coals of a maximum temperature of 300°C, a concentration of oxygen in the auxiliary combustion gas of more than 30% and a preheating temperature of auxiliary combustion gas of more than 80°C, a flame of more than bout 2,000°C can be formed. With this arrangement, it is possible to ignite fine powder coals at less energy cost.