| 摘要 |
<p>Oxygen is dissolved in an aqueous liquid by entraining small bubbles of an oxygen-containing gas in a mechanically pumped stream of the liquid, which stream is flowing downwardly at a rate exceeding the upward velocity of the bubbles, whereby the bubbles are swept downwardly in the liquid and the oxygen dissolves in the liquid. Apparatus for use in the method includes a, pump (22) and one or more down-pipes (20) extending into, or constituting part of, a vessel (20, 21) for containing the liquid, the or each pipe comprising an aerator (26) for supplying fine bubbles of oxygen-containing gas into the aqueous liquid as it is pumped downwardly through the down-pipe(s). The aerator may be a fine bubble diffuser, a venturi, or a tube 2, Figure 3 (not shown) with fine port holes or inclined tubes which produce a partial vacuum in tube 2. <IMAGE></p> |
