GB2241796A

GB2241796A - Fluidic mixers

Info

Publication number: GB2241796A
Application number: GB9005459A
Authority: GB
Inventors: Michael Joseph Bowe; Lionel Houston Ford
Original assignee: UK Atomic Energy Authority
Current assignee: UK Atomic Energy Authority
Priority date: 1990-03-10
Filing date: 1990-03-10
Publication date: 1991-09-11
Also published as: GB9005459D0

Abstract

In spiralling through a vortex chamber 6 a liquid flow experiences high resistance to achieve thorough mixing and blending. A particular application is the homogenisation of milk, the constituents of which are thoroughly mixed and blended into a homogenous and stable mixture in spiralling through the vortex chamber. <IMAGE>

Description

Fluidic Mixers The present invention concerns fluidic devices for use as homogenisers.

Homogenisation is the process of thoroughly mixing and blending the constituents of a liquid, or separate and different liquids, into a uniform homogenous and stable mixture. Thus it is known, for example, to pass milk through a homogeniser to break up the fat globules and to resist separation of the fat or cream content of the milk. In a known homogeniser, the milk is forced under pressure through openings in a plate against a solid surface for the purpose of blending the constituents of the milk.

The present invention proposes the use of a fluidic device, in particular a vortex chamber, for blending the constituents of milk into a uniform homogenous and stable mixture.

According to the present invention a process for homogenising liquids comprises passing liquid through a vortex chamber such that the liquid experiences a high resistance to flow in spiralling through the vortex chamber to achieve thorough mixing of the constituents in the liquid.

The liquid can be milk and in spiralling through the chamber from an inlet at the periphery of the chamber to a central axial outlet in an end wall of the chamber the cream or fat content is broken down to mix with the non-fat content of the milk. The breakdown of the fat content is proportional to the pressure drop across the chamber. Conveniently, the flow can be enhanced by recycling a portion of the flow emerging from the vortex chamber. The vortex chamber can be a fluidic diode having a tangential inlet to create a spiralling flow to the central axial outlet. Preferably however, the vortex chamber comprises a vortex amplifier having a radial inlet, an axial outlet and a tangential control port. A control flow at the tangential port causes the main incoming liquid flow at the radial port to spiral through the chamber to the axial port.The control flow can be taken from the flow emerging from the chamber at the axial port. The amount of control flow is adjustable.

The invention will be described further, by way of example, with reference to the accompanying schematic diagrams in which Figures 1 and 2 depict alternative embodiments for homogenising milk.

In Figure 1, a vortex chamber 1 has a tangential inlet 2 and an axial outlet 3 to receive a flow of milk in the direction indicated by the arrows. The chamber is a vortex diode. In swirling through the chamber 1 the milk encounters a resistance to flow and its constituents become thoroughly mixed. The cream or fat content of the milk is broken down and substantially homogenised milk emerges from the outlet 3.

To improve performance a part of the outflow can be recycled along path 4, which includes a pump 5, to the flow at the inlet 1.

Preferably, and as shown in Figure 2, the vortex diode is replaced with a vortex amplifier 6 having a radial inlet 7, an axial outlet 8 and a tangential control 9. As before the control is taken from the flow emerging at the outlet 7 and a selectively adjustable pump 10 is included in the flow line. In this case it is possible to vary the control flow and hence the degree of mixing in the vortex chamber.

Claims

1. A process for homogenising a liquid or liquids comprising passing a flow of the liquid or liquids through a vortex chamber such that the flow experiences a high resistance in spiralling through the vortex chamber to achieve thorough mixing of the constituents in the liquid or the liquids.

2. A process as claimed in Claim 1 which comprises recycling a portion of the flow from the vortex chamber.

3. A process as claimed in Claim 1 or 2 which comprises introducing the flow tangentially into the vortex chamber.

4. A process as claimed in Claim 1 or 2 which comprises introducing the flow radially into the vortex chamber and causing the flow to spiral through the chamber by introducing a tangential control flow into the chamber.

5. A process as claimed in Claim 4 which comprises taking the tangential control flow from the flow emerging from the vortex chamber.

6. A process as claimed in Claim 5 which comprises selectively adjusting the control flow.

7. A process as claimed in any preceding claim which comprises passing a flow of milk through the vortex chamber.

8. A process for homogenising a liquid or liquids substantially as herein described with reference to the accompanying drawings.