Supply method for liquid and supply apparatus

Abstract

A solution having a predetermined concentration is stably supplied to a use point, at which the amount of use of the solution changes, by only modifying currently-used equipment at a low cost and in a space-saving manner. In order to supply a solution containing a solute at a predetermined concentration from a preparation portion of the solution to a use point through a supply pipe, a retention portion that has no gas-liquid interface and at which the solution is retained is provided at an intermediate portion of the supply pipe. Even when the amount of use of the solution at the use point changes, the change is absorbed by the retention portion, whereby a solution having a predetermined concentration can be stably supplied to the use point. Such a retention portion is advantageous in terms of space saving since the retention portion can be formed by using, for example, a long pipe portion or a large-diameter portion of a pipe having no gas-liquid interface. Such a retention portion can be installed in existing equipment at a low cost by only slightly modifying an intermediate portion of a supply pipe.

Dependencies are inferred from the claim text.