METHOD OF AND APPARATUS FOR INTRODUCING A METERED QUANTITY OF FOREIGN LIQUID INTO A CONTINUOUS MAIN CURRENT OF LIQUID

摘要

1348227 Mixing liquids in proportions BOEHRINGER MANNHEIM GmbH 16 June 1972 [18 June 1971] 28228/72 Heading B1C [Also in Divisions B8 and F2] In a method and apparatus for metering a liquid additive into a flowing liquid without causing flow rate fluctuations, the main flow is supplied to two pipes ZZ1, ZA1 and ZZ2, ZA2 connected in parallel and interrupted by a valve member AS having a flow passage VDI and a metering passage VD2. As shown in Fig 2b the metering passage is being filled by a vacuum previously built up in the chamber VK while the main flow passes through ZZ1, VD1, ZA1. In a subsequent position, of the valve member, Fig. 2c, the flow through ZZI, ZA1 is interrupted and flow takes place through ZZ2, VD2, ZA2, the additive being swept out into the main flow and mixed in a column (S, Fig. 1, not shown) without disturbance of the flow rate. At the same time the additive inlet FFZ and vacuum chamber VK are purged by connection to the vaccum pipe KVL. Subsequently the metering passage is also purged by connection between the air inlet LZ and vacuum pipe VA, see Fig. 2d, not shown. The metering apparatus may be embodied as a rotary valve, see Figs. 3-9, not shown, which may be rotated manually or by motor in a constant sense to perform successive metering operations; it may be controlled by a timing device.