Место издания: Dundee , Год издания: 2003

Compositions of chute concrete masses excluding any carcinogenic substance were studied and tested on a chute by the SSUI in conjunction with the Kuznetsk Metallurgical Combine company. The best results were obtained with the following composition: 75% fused electrocorundum, 20% refractory clay, 5% high-alumina cement and 7.3% water (above 100%). Thermal resistance in heat changes was above 25 cycles at 800┬░C, apparent density was 2.54 to 2.75 g/cm3, compressive strength was 76.6 and 79.2 MPa at 110┬░C and 1450┬░C, respectively, slag resistance was 0.1 to 0.2 mm at 1450┬░C, firing shrinkage was 0.2% with no corrosion observed. This composition increases the service life by 10 times when compared to the composition generally used and it does not emit any carcinogenic matters. However, in view of the economic crisis and rising cost of electrocorundum, its application is limited. Therefore, we have developed compositions with high-alumina product (HAP, the waste from the Yurga abrasive works) as a replacement for electrocorundum. They are as follows: (i) 35% HAP, 20% refractory clay, 30% waste from the production of silicon carbide; (ii) 40% HAP, 20% refractory clay, 32% coke with a particle size distribution of 3 to 0 mm, 8% coke pitch. These compositions reduce their strengths by half (from 80 to 40 MPa) at 1450┬░C with other indices (slag resistance, iron resistance, apparent density and shrinkage) being the same as for compositions containing purely fused electrocorundum. Their costs correspond to that of the concrete masses generally used but the service life is 4 times longer which was proved by testing in a central chute of a blast furnace.