Since the introduction of melting acceleration technique by coal-oxygen injection in the electric are furnace operation the heat supply has changed from partial supply pattern into a new one on a large area and multi point basis, and as a result the syn- chronous melting of furnace charge has replaced the previous mode of gradually melting.

It is shown that,compared with extractive coals,gas producing ratio reduces a bit but the effective gas components CO and H2 did not reduce after adding additive.

Selecting CaO as additive,blending it into two coals in different proportions respectively,the tests of coal ash fusion characteristics are performed under condition of the infirmly deoxidized ambience.

The additives CaO or Fe2O3 were blended with the coals in different proportions respectively.

Research on flux effected to ash fusion;

Research on flux added to reduce ash fusion temperature of Huainan coal;

Mechanism of reducing ash fusion temperature by adding flux in Huainan coal;

6% containing slag is chosen as the basic slag and CaF2 is replaced by B2O3 as the fluxing agent it's found out that as the fluxing agent B2O3 is almost the same as CaF2 therefore B2O3 can be used as the pollution refining slag in place of SiO2 slag.

The slag composite contains CaO-SiO 2-Fe 2O 3-MgO-MnO 2(2?%)-Al 2O 3(3?%)-P 2O 5(2?%)and CaF 2 is used as a fluxing agent.