Assembly for the production of dispersions

Patent metadata

Field	Value
Publication number	US-9409133-B2
Application number	US-201113990825-A
Country	US
Kind code	B2
Filing date	Dec 9, 2011
Priority date	Dec 9, 2010
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

An assembly for the production of dispersions including a mixing unit ( 7 ) and a circulation tank ( 1 ) for holding liquid, the mixing unit ( 7 ) including a first solid inlet ( 8 ) for receiving a solid, a second liquid inlet for receiving the liquid, a mixing chamber where the liquid and solid are mixed, and a return outlet ( 13 ), the liquid inlet is fluidly connected to the circulation tank ( 1 ) such that liquid in the circulation tank flows to the mixing unit ( 7 ) via a circulation tank outlet ( 4 ), the return outlet ( 15 ) transferring the combined liquid and solid from the mixing chamber ( 7 ) into the circulation tank ( 1 ) via a circulation tank inlet. The circulation tank has an interior height which is configured such that a chamber exists inside the tank above the level of the liquid. Alternatively, the circulation tank inlet is permanently positioned above the liquid level or it includes a pipe configured such that the dispersion forms a film on its inner surface. Alternatively, the circulation tank includes an impeller having a diameter equal to or greater than 0.5 times the internal diameter of the tank.

First claim

The invention claimed is:

1. A continuous process for the production of dispersions in an assembly including a mixing unit and a circulation tank for holding a liquid; the mixing unit including a first solid inlet for receiving a solid, a second liquid inlet for receiving liquid, a mixing chamber for mixing liquid and solid, a return outlet, and a mixing unit pump; the circulation tank including a circulation tank outlet, a circulation tank inlet including a tank inlet pipe and the circulation tank having a wall with an inner surface, wherein the liquid inlet is fluidly connected to the circulation tank via an inlet pipe such that liquid in the circulation tank can flow to the mixing unit from the circulation tank outlet via the inlet pipe and the liquid inlet, wherein the mixing chamber is fluidly connected to the circulation tank via a liquid return pipe, the liquid return pipe being connected to the mixing unit at the return outlet and to the circulation tank at the circulation tank inlet, so that dispersion from the mixing chamber can be transferred into the circulation tank via the circulation tank inlet,
the process comprising:
providing liquid contained in the circulation tank;
drawing liquid contained in the circulation tank into the mixing chamber via the inlet pipe by means of the mixing unit pump and allowing solid material to flow into the mixing chamber via the first solid inlet to form a dispersion of solid material in the liquid; and
transferring the dispersion from the mixing chamber to the circulation tank via the circulation tank inlet,

wherein the tank inlet pipe in the circulation tank inlet is configured such that the dispersion forms a film on the inner surface and wherein the tank inlet is permanently positioned above the liquid level in the circulation tank.

2. The process according to claim 1 wherein the pipe is tangential to the inner surface such that the dispersion flows directly onto the inner surface.

3. The process according to claim 2 wherein the pipe is circumferentially tangential to the inner surface.

4. The process according to claim 1 wherein the pipe is directed towards the inner surface such that the dispersion flows directly onto the inner surface.

5. The process according to claim 1 , wherein the circulation tank has an internal diameter D T , and includes an impeller with an impeller diameter D I , wherein D I is equal to or greater than 0.5 D T .

6. The process according to claim 5 wherein D I is equal to or greater than 0.6 D T .

7. The process according to claim 5 wherein D I is equal to or greater than 0.64 D T .

8. The process according to claim 1 wherein the dispersions have a solids content equal or more than 45 wt %.

9. The process according to claim 1 wherein the dispersions have a viscosity greater than 10 Pas at a shear rate of 1 s −1 and a viscosity greater than 1000 Pas at a shear rate of 0.001 s −1 .

10. The process according to claim 2 wherein the dispersions have a solids content equal or more than 70 wt %.

11. The process according to claim 5 wherein the dispersions have a solids content equal or more than 70 wt %.

12. The process according to claim 5 wherein the dispersions have a viscosity greater than 10 Pas at a shear rate of 1 s −1 and a viscosity greater than 1000 Pas at a shear rate of 0.001 s −1 .

13. The process according to claim 5 wherein the dispersions have a viscosity greater than 10 Pas at a shear rate of 1 s −1 and a viscosity greater than 1000 Pas at a shear rate of 0.001 s −1 .

Assignees

• Baltussen Jozef Johannes Maria
• Ypma Marco
• Akzo Nobel Coatings Int Bv

Inventors

• Baltussen Jozef Johannes Maria
• Ypma Marco

Classifications

• B01F2215/0495

  Numerical values of viscosity of substances · CPC title

• B01F2215/0431

  Numerical size values, e.g. diameter of a hole or conduit, area, volume, length, width, or ratios thereof · CPC title

• B01F23/53 Primary

  using driven stirrers · CPC title

• B01F3/1271 Primary

  Operations & Transport · mapped topic

• B01F5/106

  Operations & Transport · mapped topic