Device for measuring the amount of gas dissolved in a liquid

Abstract

Beer fermentation apparatus comprises a main pipe for transporting a water-entrained mixture of wort, yeast and gas to a fermentation tank. A measuring device is mounted in a by-pass circuit of the main pipe for measuring the amount of gas dissolved in the water, the device comprising a vertically disposed measuring chamber having an inlet at its lower end and an outlet at its upper end which are connected to upstream and downstream portions of the main pipe for flowing the mixture through the measuring chamber. The chamber inlet is located a sufficient distance above the lowermost end of the chamber so as to effect formation of a relatively stagnant flow region which is substantially free of gas bubbles in the measuring chamber beneath the level of the inlet during flow of the water-entrained mixture through the measuring chamber. A gas-sensitive element extends downwardly in the measuring chamber into the stagnant flow region for measuring the amount of gas dissolved in the mixture and due to the relative locations of the chamber inlet and outlet and the location of the gas-sensitive element, the gas bubbles and lighter mixture particles entrained in the water flow in the inlet upwardly through the measuring chamber and out the outlet while the heavier mixture particles entrained in the water tend to flow downwardly and settle in the stagnant flow region thereby minimizing erroneous measurements which would otherwise occur due to the presence of gas bubbles in the vicinity of the gas-sensitive element.