The corundum castable samples with different nano-CaCO3 contents are prepared by taking tabular corundum, alumina powder, commodity calcium carbonate, Alphabond300 as main raw materials and FS10 as water reducer, and their apparent porosities, bulk densities and crushing strengths after the heat treatments at 1 000℃ and 1 600℃ are measured. The microstructures of the materials are observed with scanning electronic microscope. The result shows that when the water reducer is added in a constant amount, with the increase of nano-CaCO3 addition amount the water demand is increased gradually, apparent porosity is raised and crushing strength is heightened inch by inch. Under the condition that the basically same flow values of the castables are controlled, apparent porosity is enlarged obviously, but crushing strength is heightened gradually with the increase of the nano-CaCO3 addition amount.

Silicon powder and aluminum powder are added into the matrix of corundum based refractory, β-Sialon is formed through in-situ nitrogenizing reaction and it is used to prepare β-Sialon bonded composite phase material. The effect of β-Sialon formed amount on the physical property, mechanical property, thermal shock resistance and so on of the material is studied. The phase composition and microstructure of the material are analyzed by XRD and SEM.

By using alumina hollow balls with grain sizes of 5~3mm, 3~2mm, 2~1mm and 1~0.2mm as raw material and adding SiO2 micro-powder the gel bonded alumina hollow ball castable is formed. The effect of pre- synthesized magnesia-alumina spinel on the properties of gel bonded alumina hollow ball castable is studied. The property determination of spinel specimens adding different amounts of spinel is  carried out with various kinds of refractory product determining and analytical equipment and instrument.In combination with the theoretical analysis done with magnesia-alumina-silica phase diagram, the result shows that the addition of spinel promotes the sintering function of corundum phase in castable, raises the cold crushing strength and apparent porosity of gel bonded alumina hollow ball castale and reduces the bulk density of it. Spinel has the strengthening function to the matrix of the gel bonded alumina hollow ball castable and is favorable to improve the thermal shock resistance of it.

According to the features of Maerz lime kiln and in combination with the production experi ence of Maerz lime kiln of Hansteel, it is described that the equipment needs to be inspected and corre sponding measures are to be taken when the temperature of 11m lime discharge platform is too high. The good temperature control of 11m discharge platform of Maerz lime kiln is favorable to produce high quality product and prolong the service life of the lime kiln.

The method for direct determination of the silicon content in industrial silicon with hydrofluoric acid weight method is described. Sample is decomposed with nitric acid and hydrofluoric acid to form silicon tetrafluoride for removal and then it is burned in a high temperature oven. According to the mass difference before and after treatment of hydrofluoric acid, the mass percentage of silicon is calculated by subtracting the increment of ferric oxide formed by iron oxidation. The relative deviation of the method is below 0.20%.

In the production of siliceous bricks for hot blast stove, the method of mixing loading of checker bricks with other shaped bricks that is used in the past is changed and the centralized loading of checker bricks on the selected kiln cars in “two-step pit” location in tunnel kiln is done and the brick setting method is improved. Therefore the finished product qualified rate of checker bricks is raised and no influence on finished product rate of other shaped bricks is ensured.