GB2299522A - A multi-stage turbo mixer - Google Patents

Abstract

The mixer comprises a housing having a radial inlet 2 and tangential inlets 3,4 at one end and a tangential outlet (5, Fig 1) at the other end. The multi-stage turbine includes inlet and outlet turbines 9,11 and an intermediate turbine 10. Static plates 13 and 14, having orifices (16,19, Figs 6 and 7), are disposed between the turbines.

Description

A Mixer The present invention relates to a mixer, and more specifically, but not exclusively, to an on-line mixer for mixing together liquids and/or liquids and solids.

The mixers currently known have a mixing body provided with two inlets, through which a homogeneous product in powder form and a liquid are respectively supplied, and an outlet through which the composite mixture formed by the two components introduced emerges.

It is usual for there to be disposed inside the mixing body various turbines which have the function of impelling the products introduced into the machine towards the outlet, there being disposed between them a number of static plates which assist in the mixing of the said products.

The problems in these mixers are basically caused by the fact that the mixing body is provided with only two inlets, for the entry of liquid and a product in powder form, because their use centres on the mixing of homogeneous products in powder form with liquids.

In view of the fact that they usually have various turbines which impel the mixture and between which static plates are interposed, the efficiency of these mixers is essentially determined by the configurations of the turbines and plates, and also the disposition thereof, while these features bring about a greater or lesser mixing capacity, as a function of the different types of flow described by the components of the mixture inside the mixing body and by the number of changes of direction of the said flow.

In order to remedy the limitations of the current mixers, the improved mixer forming the subject of this invention was devised, which has a series of design features making it possible to achieve mixtures of liquids and mixtures of solids, liquids and solutions and dispersions of pulverulent solids.

These features are brought about, on the one hand, by the fact that the same mixing body can have a radial inlet for pulverulent solids and a tangential inlet for liquids or various tangential inlets for liquids; and on the other hand, by the configurations both of the turbines and of the static plates disposed between them, which compel the mixture to make continuous changes in type of flow and direction, for the purpose of obtaining a total mixture of the products which enter to form part therof.

An embodiment of the present invention provides a mixer comprising a housing, a plurality of openings in the housing for input and output of liquid and solid particles, and turbine means, an input end of the housing including a radially extending inlet and at least one non-radially extending inlet, an output end of the housing including a non-radially extending outlet, the turbine means being provided between the two ends inside the housing and including at least an inlet and an outlet turbine, and a first static plate, disposed midstream of the turbines, for use in controlling the flow of mixture from the inlet turbine to the outlet turbine.

Preferably, the turbine means includes an intermediate turbine provided midstream of the inlet and outlet turbines, and a second static plate, disposed midstream of the intermediate and outlet turbines, for use in controlling the flow of mixture from the intermediate turbine to the outlet turbine, the first static plate being disposed midstream of the inlet and intermediate turbines.

Preferably at least two non-radially extending inlets are provided at the inlet end and means may be provided selectively to close the inlets. The turbines may be mounted on a common drive shaft which is sealably and rotatably mounted in one of the ends of the housing. The inlet turbine may comprise a plurality of helical blades. The or each static plate may be provided with one or more openings therethrough for changing the direction of the circulating mixture.

The intermediate turbine may comprise a plurality of radially extending vanes. Each vane may be provided with an inwardly extending removed section.

The openings in the second static plate are preferably holes of smaller size than those of the first static plate and may extend parallel to the drive shaft.

The outlet turbine preferably comprises a plurality of radially extending vanes. Each vane may be provided with an inwardly extending removed section. The outlet may be provided radially outermost of the outlet turbine.

The inlets may be provided axially spaced from the inlet turbine.

A nozzle may be provided upstream of the inlet turbine. The or each set of vanes preferably have a substantially 900 pitch.

An alternative embodiment of the present invention provides a mixer which has a mixing body.

provided, at one of its ends, with two or more tangential inlets and, at the opposite end, with a tangential outlet; while there is inserted longitudinally in the said mixing body, via a mechanical seal, a drive shaft on which least three turbines are mounted which impel the mixture towards the outlet, and there are interposed, between the said turbines, a number of static plates provided with orifices through which the mixture impelled by the turbines passes.

Reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 shows a front view of the mixing body, in which the various inlets for products and the outlet for the mixture can be seen.

Figure 2 shows a diagrammatic view, in elevation, of the mixing body, partially cut away through a vertical plane, in which the alternate disposition of the turbines and fixed static plates can be seen.

Figure 3 shows a view, in elevation, of the inlet turbine.

Figure 4 shows a sectional view of the intermediate turbine, cut away vertically.

Figure 5 shows a sectional view of the outlet turbine, cut away vertically.

Figure 6 shows a view, in elevation, of the static plate located between the inlet turbine and the intermediate turbine.

Figure 7 shows a view, in elevation, of the static plate disposed between the intermediate turbine and the outlet turbine.

PREFERRED EMBODIMENT OF THE INVENTION As can be seen in the figures, which are provided with reference numerals, this mixer has a mixing body (1) which defines, near one of its ends, a radial opening (2) and two tangential openings (3 and 4), which respectively form a possible inlet for pulverulent products and two possible inlets for liquid; the said mixing body having, near the opposite end, a tangential opening (5) via which the mixture emerges from the body (1), regardless of whether the said mixture is constituted by liquids or by liquids and pulverulent solids.

In order that the operative inlets to the mixer may be selected as a function of the type of mixture to be achieved, provision has been made for each of the inlets (2, 3 and 4) to have removable caps (6), the function of which is to achieve hermetic sealing of those inlets which are to remain inoperative, so that the product supplied via the said inlets does not enter to form part of the mixture.

Inside the body (1) there is inserted longitudinally, via a mechanical seal (7), a drive shaft (8) on which an inlet turbine (9), an intermediate turbine (10) and an outlet turbine (11) are mounted between the product inlet openings and the mixture outlet opening, there being respectively disposed in front of each of the turbines a nozzle (12), a first static plate (13) and a second static plate (14), which are mounted on the internal wall of the body (1).

The inlet turbine (9) is constituted by a plate having, on its periphery, a plurality of machined portions which define various helicoidal blades (15) of fixed pitch, the function of this inlet turbine (9) being to impel the components of the mixture while giving rise to a helicoidal flow.

The static plate (13) has a plurality of straight orifices (16) which compel the mixture to change the helicoidal direction imparted by the turbine (9), the flow of mixture leaving the straight orifices (16) in multiple jets parallel to the drive shaft.

The second turbine (10) has a number of straight blades (11) which are disposed radially and have a central groove (18) on their periphery; this turbine impels the mixture of products while compelling it to rotate, the grooves (18) succeeding in creating a number of major turbulences in the mixture which promote its homogeneity.

The static plate (14) has a plurality of orifices (19) parallel to the drive shaft (8) and of smaller diameter than those defined in the plate (13); these orifices (19) divide up the mixture and compel it to change direction again.

The outlet turbine (11) has a number of straight blades (20) of greater width than those of the other turbines and having, on their periphery, a groove (21) that sets up turbulences in the mixture, which is impelled by this turbine towards the outlet opening (5).

It is not deemed necessary to extend this description any further in order for any person skilled in the art to understand the scope of the invention and the advantages derived therefrom.

The terms in which this memorandum has been couched must always be taken in their broad and non-limitative sense.

The materials, shape, size and disposition of the elemente will be capable of variation, always assuming that does not presuppose any alteration in the essential features of the invention, which are claimed below.

Claims (9)

CLATM

1.- Improved mixer of the on-line type, which contains a mixture body, flanges for input and output of components as liquids and solid particles, and turbines equipped by blades who drive the direction of mixture, characterised in that it presents a mixture body (1) which in one of its ends are defined a radial flange (2) and two tangential flanges (3) and (4) for products inlet, and next to the opposite end a tangential flange (5) for the mixture outlet; inside of mixture body (1) is introduced a drive shaft < s) whereon are mounted; an inlet turbine (9), an intermediate turbine (10) and an outlet turbine (11), respectively disposing before every turbine a nozzle (12), a first static plate c13) and a second static plate t14).

2.- mixer, according to the former claim, characterised in that every of the inlets (2, 3 and a) is provided with withdrawable cover plates (6) which enable to select the operative inlets.

3.- Mixer, according to the former claims, characterised in that the drive shaft enters in the mixture body through a mechanical sealing, same solidary to one of its ends.

4.- Mixer, according to the former claims, characterispd in that the inlet turbine (9) is constituted by a plate which peripherically presents a plurality of mechnaizations that defined various helicoidal blades (15 of fixed thread pitch.

5.- MLxP; according to the former claims, characterised in that the static plate (13) presents a plurality of straight holes (16), of equal diameter, provided for changing the direction of the circulating mixture.

6.- Mixer, according to the former claims, characterised in that the second turbine (10) presents the blades (11) straight and radially disposed and that they peripherically presents a central cut (IS).

7.- Mixer, according to the former claims, characterised in that the static plate (14) presents a plurality of holes (19) parallel to the drive shaft < 8) and of minor diameter as those provided for plate (13).

8. - Mixer, according to the former claims, characterised in that the outlet turbine (11) presents the blades (20) straight, and of bigger thickness as those provided for the other turbines, and that they peripherically presents a central cut (21).

9. A mixer substantially as hereinbefore described with reference to, and as shown in, Figures 1 to 7 of the accompanying drawings.