GB1027846A - Improvements in or relating to the mixing or heating of materials with liquids - Google Patents

Abstract

In the continuous production of a neutral sodium sulphite solution of 5 to 50% concentration, a caustic solution (50% commercial NaOH) is injected through the central pipe 18 and sulphur dioxide through the outer plenium chamber 21 (see Fig. 3). <PICT:1027846/C1/1>ALSO:<PICT:1027846/C3/1> <PICT:1027846/C3/2> In the process of mixing a liquid with a second material which may be solid liquid or gaseous, the second material is injected as a plurality of streams into an elongated rapidly rotating zone of the liquid. The liquid may be admitted by a tangential pipe into a cylindrical container to form a rotating column, and the second material injected by an axial pipe having a closed end and radially directed orifices, see Fig. 1 (not shown). In another arrangement, Fig. 2, the container 8 may be surrounded by a planum chamber 10 to which the second material is supplied by a pipe 11 and from which it enters the container through orifices 12. Both arrangements may be combined, Fig. 3. Nozzles or pipe extensions may be used instead of simple orifices and in the arrangements of Figs. 2 and 3 may inclined at an angle of 400 degrees to 60 degrees from the radius to augment rotation of the body of liquid. Polymerization.-The apparatus and process of Fig. 2 are applicable to a continuous emulsion polymerization process in which 10 to 40% of a butadiene-styrene mix, or of vinyl chloride, may be mixed with an aqueous medium containing a catalyst, soap or other additive. Alternatively, the catalyst, soap &c. may be added through the central chamber 18 of Fig. 3, the monomer being injected from the plenium chamber 21. Starch.-The apparatus of Figs. 1 or 2 may be used further gelatinization of starch, the aqueous cold water starch slurry being introduced axially in Fig. 1 or through the plenium chamber of Fig. 2 into a rapidly rotating body of caustic soda solution of about 120 G/1 (equal to 3N-NaOH) at 230 DEG F. to provide a starch solution of about 30 G/l. In the apparatus of Fig. 3 the starch may be injected axially and the materials simultaneously heated by the injection of steam through the plenum chamber; a digestion temperature of 240-270 DEG F. for 10 minutes will produce a flocculating agent for the Bayer red hand process of superior flocculating and settling properties.