Vertical cylindrical mixing vessel for liming sugar juice - enables extremely fine pH control in minimum floor space to be achieved

摘要

The vessel is of the vertical cylindrical type and it is divided into superimposed, cylindrical chambers by perforated, horizontal partitions. A vertical, rotary shaft extends coaxially through the chambers and is fitted with agitator blades in some, at least, of the chambers. The shell of the vessel is now extended downwards to contain a cylindrical receiver. The rotary shaft extends into the receiver where it is fitted with agitator blades. This receiver constitutes the principal liming zone while preliming is carried out in the superimposed chambers. Flow passages between adjacent chambers are fitted adjustable flow restrictors, e.g. valves, shutters etc. Alternate chambers pref. have different agitator blades and internal profiles. This induces centrifugal circulation in one chamber and centripetal circulation in the next. Through one partition liq. flows upwards through an axial passage and downwards via edge passages. Adjacent partitions have reverse flow conditions. The edge passages can be fitted with pivoted, flow-control shutters which can be adjusted from the exterior. By building the preliming chambers on top of the principal liming receiver, the installation occupies min. floor space. Controlled recycling via the preliming chambers facilitates extremely fine adjustment of pH value.