| 摘要 |
The catalyst is provided for anhydrite mortars comprising, by weight, from 25 to 80 % of anhydrite and 75 to 20 % of moist neutral granulates passing through the 50-mm mesh and retained on the 4-mm mesh, where the catalyst is introduced in the weight dosage of 1 to 1.6 %. It consists of a mixture comprising, by weight, from 34 to 58 % of a mixture of sulphates, from 40 to 60 % of a mixture of calcined oxides and from 2 to 6 % of pulverulent silica, the mixture of oxides comprising, in the case of at least 70 % of its weight, alumina and lime, these two oxides in a weight ratio of between 0.8 and 1.25, while the mixture of sulphates consists, by weight, of 2 to 3 parts of potassium sulphate, of 4 to 5 parts of calcium sulphate hemihydrate and iron sulphate heptahydrate and/or zinc sulphate, the iron sulphate, when it is present by itself, accounting for 12 to 16 parts and the zinc sulphate, when it is present, being substituted for all or part of the iron sulphate in a proportion of one part of zinc sulphate per two parts of iron sulphate. Application to the support of mines, by spraying with a lance with 8 to 16 % of water relative to the anhydrite.
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