Mining gypsum

摘要

The invention describes the protection of building materials containing gypsum or consisting of pure gypsum and also calcium sulphate dihydrate as packing material for underground mining against the action of anaerobic bacteria (H2S liberation), which is characterised in that the materials have added to them alkalis or alkaline earth compounds such as NaOH, Na2CO3, CaO, Ca(OH)2 etc. to increase the pH to greater than pH 11 and, additionally, oxygen-liberating agents such as, for example, potassium persulphate, perborates etc. which, in the alkalinity of the compositions, slowly release the oxygen and thus prevent the liberation of hydrogen sulphide by anaerobic bacteria.