JP3078925U - Nozzle device of dissolving device to dissolve solid in solvent - Google Patents

Abstract

The invention relates to a nozzle device (3) in a dissolving apparatus for dissolving a solid (F) in a solvent, preferably for dissolving a powdery solid in water. The nozzle device comprises a mixing tank (1) from which the solvent-solid suspension is removed in the bottom part (1a) thereof whereupon the suspension is subsequently pumped outside of the mixing tank (1) through a circulation line (6) and is returned once again. The aim of the invention is to reduce the dissolving time in the mixing tank (1) with regard to that of prior art dissolving apparatuses of the generic type and to simplify the apparatus itself. To these ends, the invention provides that the suspension is introduced into the mixing tank (1) via the nozzle device (3) arranged in the bottom part (1a) of said mixing tank. In addition, the invention provides that the nozzle device, starting from a feed tube (3a) and when viewed in a direction of flow, branches into an annular gap nozzle (3c) and a tubular nozzle (3d), that the annular gap nozzle (3c) generates an annular gap flow (R), which is oriented in an essentially transversal manner with regard to the longitudinal axis of the mixing tank (1), and that the tubular nozzle (3d) generates a driving flow (T) which, with regard to the longitudinal axis of the mixing tank (1), has both an axial and tangential directional component oriented toward the top part (1c) of the mixing tank.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 According to the invention, a suspension of the solvent and the solid is removed from the bottom of the mixing tank, and then the suspension is circulated outside the mixing tank through a circulation line and supplied to the mixing tank again. The present invention relates to a nozzle device of a dissolving device for dissolving the compound in a solvent.

[0002]

[Prior art]

 In the beverage industry, there is often the problem of turning certain additives as solid powders into aqueous solutions, for example citric acid or artificial sweeteners. By making the additive in this aqueous solution, it is possible to carry out the subsequent treatment within the production process of each beverage. First, the solids need to be suspended in a solvent, eg, water, to dissolve each solid. It is known that a mixing tank containing the required amount of water is charged with the amount of solid to be dissolved and subsequently suspended using a stirrer. This stirring device is composed of, for example, a motor driven stirring member. In addition, by circulating the suspension of the solvent and the solid outside the mixing tank through a circulation line and feeding it again to the mixing tank, the stirring action and the suspension action are improved. In this case, the suspension is usually removed from the bottom of the mixing tank and fed back into the region of the cylindrical outer wall. When dissolving citric acid or an artificial sweetener in water, such a dissolution apparatus requires a dissolution time of, for example, 15 to 20 minutes.

In addition to the basic requirement of shortening the dissolving time as much as possible, in particular the known motor-driven agitator of the dissolving apparatus is not advantageous. This is because the cost of the stirrer is high and the stirrer is an embedded device that is difficult to clean. This built-in device is often difficult or inadequate to clean with the so-called automatic cleaning in place (CIP) cleaning method.

[0004]

[Problems to be solved by the invention]

 The problem of the present invention is to reduce the dissolving time in the mixing tank and to simplify the device itself as compared to known dissolving devices of the kind mentioned at the outset.

[0005]

[Means for Solving the Problems]

 The problem is that the suspension of solvent and solids is removed from the bottom of the mixing tank, and then the suspension is circulated outside the mixing tank via a circulation line and fed back into the mixing tank, where the solids are removed. In a nozzle device of a dissolving device for dissolving a solvent, particularly a powdery solid in water, the supply of the suspension to the mixing tank (1) is performed by a nozzle device (1a) arranged in the bottom portion (1a) of the mixing tank. This nozzle device branches into an annular gap nozzle (3c) and a pipe nozzle (3d) when viewed from the supply pipe (3a) in the flow direction, and the annular gap nozzle (3c) is This annular gap flow is oriented transversely to the longitudinal axis of the mixing tank (1), the tube nozzle (3d) generates a propulsion flow (T), With respect to the vertical axis of the mixing tank (1), It was solved by Nozzle apparatus characterized by having an axial component and a tangential component oriented towards the part (1 c). Advantageous embodiments of the proposed nozzle arrangement are described in the other claims.

[0006] Unlike known dissolving devices, the suspension is supplied to the mixing tank from the bottom rather than from the outer peripheral wall of the mixing tank. For this purpose, a nozzle device is provided which branches into an annular gap nozzle and a pipe nozzle when viewed from the supply pipe in the flow direction. At that time, the annular gap nozzle generates an annular gap flow, which is oriented transversely to the longitudinal axis of the mixing tank. The remaining partial stream of the supplied suspension is discharged via a tube nozzle, which generates a propulsion flow in the mixing tank, which propulsion flow is, with respect to the longitudinal axis of the mixing tank, at the head of the mixing tank. It has both axial and tangential components pointing toward.

[0007] Due to the above characteristics, convection is generated in the mixing tank by the tube nozzle. This convection captures the entire tank contents and circulates the tank contents vertically and tangentially. The other suspension partial flows exiting the annular gap nozzle intersect, in particular, with downwardly directed convection, on the one hand resulting in intense mixing of the suspension and, on the other hand, suspension conditions due to very energetic transverse flows. Is improved. Since the removal and supply of the suspension takes place via the bottom of the mixing tank, convection and annular gap flow necessarily cross. Thus, by convection, the entire contents of the tank are systematically incorporated into the mixing and dissolving processes. This ensures that stagnation areas in the tank where material exchange conditions are undesirable are avoided.

[0008] It has been found to be advantageous if the annular gap nozzle is designed to extend over a spray angle of approximately 360 °. By this means, the annular gap flow is discharged over the cross-sectional area of the mixing tank and thereby intersects with the convection flowing downward over the entire circumference of the cylindrical outer wall of the mixing tank.

[0009] The proposed nozzle arrangement is advantageous because it is simplified if the supply tube is guided through a discharge housing which serves for the removal of the suspension from the bottom part. In this case, it is only necessary to provide one opening at the bottom of the mixing tank.

If the feed tube is arranged coaxially in the bottom part, the apparatus is further simplified and the flow in the mixing tank is made sufficiently axially symmetric, so that very effective melting conditions and Suspension conditions arise.

The dissolution and suspension conditions are furthermore such that the solids to be suspended and dissolved are not supplied directly to the mixing tank, but rather to a suspension which is circulated outside the mixing tank. Greatly improved. For this purpose, it is proposed that the supply device for the solids opens into a suction line provided between the discharge housing and the circulation pump.

The average flow velocity in the supply pipe is v = 2.5 to 3 m / s, and the average flow velocity in the annular gap nozzle is v ₁ = 10 to 15 m / s, particularly 13.5 to 14.4 m / s. s and the cross-section of the nosul device is measured such that the average flow velocity in the tube nozzle is v ₂ = 4-6 m / s, especially 4.5-5.4 m / s, Optimal conditions for suspension and dissolution occur.

[0013]

[Embodiment of the invention]

 An embodiment of the nozzle device proposed by the present invention is shown in the drawings. Next, this embodiment will be described. The dissolving device (FIG. 1) substantially comprises a mixing tank 1, a housing 2, and a circulation line 6. This mixing tank has a bottom part 1a, a cylindrical outer peripheral wall part 1b and a head part 1c. The housing is flanged to the bottom part 1a and comprises a discharge housing 2b and an inflow housing 2a arranged therebelow. The circulation line 6 exits from the discharge housing 2b and opens to the inflow housing 2a. The circulation line 6 includes a suction line 6a connecting the discharge housing 2b and the circulation pump 5, and a pressure line 6b guided from the circulation pump 5 to the inflow housing 2a. A supply device 4 for the solid F opens into the suction line 6a.

A nozzle device 3 penetrates from the inflow housing 2a through the discharge housing 2b and reaches the bottom area of the mixing tank 1 through the bottom opening 1d of the bottom part 1a. The nozzle device 3 includes a supply pipe 3a (FIG. 2). The supply pipe 3a starts from a partition wall (not shown) arranged between the inflow housing 2a and the discharge housing 2b, and the other end is defined by a lid 3b, and is provided between the end of the supply pipe 3a and the lid 3b. An annular gap nozzle 3c is formed at the bottom. At this time, the lid 3b is connected to the supply pipe 3a via at least one connecting web 3e. The lid 3b is furthermore provided with a centrally located opening, to which the tube nozzle 3d is connected. The pipe nozzle 3d is formed such that the outlet on the side opposite to the lid 3b faces in the following direction. That is, the mixing tank 1 is formed so as to have an axial component directed toward the head portion 1c and a tangential component. The vertical angle of attack of the tube nozzle 3d is indicated by α in FIG. 2 and the tangential component results from the tangential angle of attack indicated by β in FIG.

The suspension and dissolution of the solid F in the solvent are performed as follows. First, the required amount of solvent, generally water, for the amount of solid F to be dissolved is placed in the mixing tank 1. Then, water is sucked by the circulation pump 5 from the bottom area of the mixing tank 1 and the discharge housing 2b connected thereto through the circulation line 6, and then through the inflow housing 2a and the supply pipe 3a connected thereto, and on the way. It is again supplied from the annular gap nozzle 3c and the pipe nozzle 3d to the mixing tank 3d.

The solid F is continuously supplied from the supply device 4 to the suction line 6a. This suspension of solid F and solvent reaches the inflow housing 2a via the circulating pump 5 and the pressure line 6b and from there on the way through the supply pipe 3a to the annular gap nozzle 3c and to the pipe nozzle 3d. . At this time, the cross sectional area A in the supply pipe 3a is measured so that the average supply speed of the circulation flow S formed in the supply pipe 3a is about v = 2.5 to 3 m / s. Is preferred. The propulsion flow T flows out of the pipe nozzle 3d. This propulsion flow T has a pipe cross-sectional area A₂ Based on the tube speed v₂ = 4-6 m / s, especially 4. It is preferable to have 5 to 5.4 m / s. Propulsion flow T generates convection K in the mixing tank. This convection flows upwards on the one hand and tangentially on the other hand, and becomes a substantially downward flow within the area of the cylindrical outer peripheral wall portion 1b. This downward flow intersects with the annular gap flow R generated from the annular gap nozzle 3c in the bottom area of the mixing tank 1. Based on this crossing flow, strong suspension and mixing movements occur. Suction flow S corresponding to circulation flow S^* Exits the mixing tank 1 through the bottom opening 1d. Annular gap Cross-sectional area A of annular gap of nozzle 3c₁ Is the average annular clearance velocity v ₁ = 10 to 15 m / s, particularly preferably 13.5 to 14.4 m / s.

It has been found that a dissolution time of, for example, 5 minutes or less is achieved with the proposed nozzle device. On the other hand, similar known dissolving devices require a dissolving time of 15 to 20 minutes for the same amount of solid F.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view schematically illustrating one embodiment of a mixing tank and a nozzle device disposed therein, along with other portions of the schematically illustrated dissolving apparatus.

FIG. 2 is an enlarged longitudinal sectional view schematically showing one embodiment of a portion of the nozzle device indicated by “X” in FIG. 1;

FIG. 3 is a plan view schematically showing one embodiment of the nozzle device of FIG. 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Mixing tank 1a Bottom part 1b Cylindrical outer peripheral wall part 1c Head part 1d Bottom opening 2 Housing 2a Inflow housing 2b Discharge housing 3 Nozzle device 3a Supply pipe 3b Cover 3c Annular gap nozzle 3d Tube nozzle 3e Connection web 4 Supply device 5 Circulation pump 6 Circulation line 6a Suction line 6b Pressure line F Solid R Annular gap flow T Propulsion flow S Circulation flow S ^* Suction flow A Supply cross section A ₁ Annular cross section A ₂ Tube cross section X Nozzle device α Vertical direction Angle of attack β Angle of attack in the tangential direction v Average flow velocity in the supply line v ₁ Average flow velocity in the annular gap nozzle v Average flow velocity in the ₂ pipe nozzle

Claims (7)

[Utility model registration claims] 1. A suspension of solvent and solids is taken from the bottom of the mixing tank, and the suspension is subsequently circulated outside the mixing tank via a circulation line and fed again to the mixing tank. In a nozzle device of a dissolving device for dissolving the compound in a solvent, the supply of the suspension to the mixing tank (1) is performed via a nozzle device (3) arranged in a bottom portion (1a) of the mixing tank. The nozzle device branches into an annular gap nozzle (3c) and a pipe nozzle (3d) as viewed from the supply pipe (3a) in the flow direction, and the annular gap nozzle (3c) generates an annular gap flow (R). The annular interstitial flow is transverse to the longitudinal axis of the mixing tank (1), the tube nozzle (3d) generates a propulsion flow (T), and this propulsion flow is relative to the longitudinal axis of the mixing tank (1). , Facing the head (1c) of the mixing tank A nozzle device having an axial component and a tangential component. 2. The nozzle device according to claim 1, wherein the dissolving device for dissolving the solid in the solvent is a dissolving device for dissolving the powder solid in water. 3. The annular gap nozzle (3c) is approximately 360 °
2. The nozzle device according to claim 1, wherein the nozzle device extends over an injection angle of the nozzle. 4. The nozzle according to claim 1, wherein the supply pipe of the nozzle device is guided through a discharge housing serving to remove the suspension from the bottom part. apparatus. 5. The nozzle device according to claim 1, wherein the supply pipe (3a) is arranged coaxially with the bottom part (1a). 6. The solid supply device (4) opens into a suction line (6a) provided between the discharge housing (2b) and the circulation pump (5). Nozzle device according to one. 7. An average flow velocity (v) in the supply pipe (3a) is v = 2.5 to 3 m / s, and an average flow velocity (v ₁ ) in the annular gap nozzle (3c) is v _1.
= 10 to 15 m / s, and then the average flow velocity in the tube nozzle (3d) _{(v 2)} is _v 2 = _4~6m / s at a nozzle device according to any one of claims 1 to 5.