Salt-mine preservation method - uses solids of compression strength greater than rock pressure and gas cushion, greatly reduces risk of roof cracking

摘要

Salt mines are finally and safely preserved using solids and free liquids. The mine is filled partly or completely with brine, after which solids, mostly of compression strength greater than the rock pressure and of grain size such that the rock salt is permentantly prevented from flowing through the intervening spaces, are delivered into it. The brine is at least partly extracted, and a cushion of gas or air formed in the spaces. Finally part of the latter are filled with liquids which do not dissolve the salt or solids. ADVANTAGE - Greatly reduces risk of roof cracking.