JPH01215238A - Method and apparatus for centrifugal removal of milk - Google Patents

Abstract

PURPOSE: To decrease the quantity of generated bacteria condensed object by drawing the condensed object, which is led out through a nozzle, from the central range of a condensed object chamber and returning it to the supply part of a concentric drum. CONSTITUTION: Milk is supplied through a supply part 12 into a centrifugal drum 1 and let flow through a flow-in chamber 2. and a passage 3 into a separate plate setting 4 and the bacteria separated from the milk is moved into a condensed object chamber 5. The partial stream of condensed object having a little bacteria is led out of the condensed object chamber 5 of the centrifugal through a lead-out passage 6 and a nozzle 7 and returned through a lead-out mechanism 9, condensed object flow-out part 10 and return guide 11 into the supply part 12 with no omission. The bacteria integrated on the surrounding wall of the drum is periodically conveyed out of the concentric drum 1 through a carry outlet 14.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a method for centrifugally sterilizing milk, in which milk is supplied to a feed section of a centrifugal drum, and in the concentrate chamber of the one-core drum. The centrifuged bacteria-containing concentrate is accumulated, a portion of this concentrate is drawn out of the centrifugal drum through a outlet passage provided with a nozzle, and the remaining concentrate is passed through a spout provided on the outer wall of the drum. It relates to a type of equipment that is periodically carried out via a carry-out note. Furthermore, the invention relates to a device for carrying out the above method.

[Conventional technology]

Processes of this type are known and are advantageously used for sterilizing cheese-making milk (K) and drinking milk (Trinkmil, ch 2 ). Suitable centrifuges for carrying out this process can be found, for example, in West German Patent Application No. 29
13406.

Approximately 3 inches of the milk quantity supplied via the feed section of the centrifugal drum is withdrawn as bacteria-containing concentrate via a discharge channel equipped with nozzles. Another 0.3 g of the feed is periodically discharged as bacteria-containing concentrate via the discharge hole of this centrifugal drum. The bacterial concentrate thus obtained contains, inter alia, bacterial strains that have an adverse effect on cheese quality. The two partial streams are then combined again and subjected to a heat treatment in a special sterilization device, in which case the combined bacterial strains are killed. The sterilized concentrate can then be added back to the kettle milk. However, when sterilizing drinking milk, it is not allowed to reintroduce the sterilized bacterial concentrate into the drinking milk, so that the amount of bacterial concentrate produced is lost when producing the drinking milk.

In fact, there are even moves to ban the addition of sterilized bacterial concentrates to dairy products in principle. This bacterial concentrate can then only be used as low-paying feed.

[Problem to be solved by the invention]

The problem of the present invention is to provide a method for centrifugal sterilization of milk, which makes it possible to significantly reduce the amount of bacterial concentrate produced. This is achieved by withdrawing the concentrate from the central region of the concentrate chamber and returning it to the supply of the centrifugal drum.

Surprisingly, it has been found that, using the method according to the invention, it is possible to return the entire concentrate quantity drawn off via the nozzle to the feed without adversely affecting the quality of the sterilized milk flowing out. found.

This is based on the fact that the portion delivered via the nozzle is drawn from the central region of the concentrate chamber, where only a small amount of bacteria is present. That is, while the bacteria contained in the concentrate accumulates particularly on the peripheral wall of the drum near the outlet, the remaining components of this concentrate, fats and proteins, take their path through the outlet passage and nozzle.
Returns do not result in a significant increase in bacterial counts in the incoming milk. This does not result in a predictable increase in the number of bacteria in the sterilized milk.

The range in which the partial quantities delivered via the nozzle are derived is
The choice should be made such that skimmed milk with as low a bacterial content as possible is drawn off on the - side, while still not allowing fat particles to be removed along with the other side. Otherwise, this skimmed milk would be spoiled.

In the case of known centrifugal drums, both partial volumes of the resulting bacteria-containing concentrate are drawn off from the peripheral wall of the concentrate chamber.

Both portions therefore have high bacterial concentrations.

Therefore, returning the drawn-off part quantity via the outlet channel equipped with a nozzle to the supply of the centrifugal P ram gradually increases the bacterial concentration in the outlet of the centrifuge, and thus the sterilized This may have an adverse effect on the quality of milk produced.

It has been found possible to have the passage leading to the nozzle start from the central area of the concentrate chamber, thereby drawing off almost sterile skim milk, without any disadvantage to the separation effect of the centrifugal drum. The withdrawal of this partial quantity is therefore only necessary in order to exert a suction effect on the bacteria in the concentrate chamber so that these bacteria migrate to the peripheral wall of this concentrate chamber.

Without this suction effect, the separation effect would be significantly poorer.

In one advantageous embodiment of the invention, the concentrate discharged via the nozzle is divided into two partial streams, of which the first partial stream is returned to the feed of the centrifugal P ram and the second partial stream is conveyed. The concentrate flowing out from the outlet is merged with this second
The amount of the partial stream is adjusted depending on the amount of concentrate exiting the outlet so that after this merging, a constant output concentrate stream is produced. This is advantageous for the subsequent sterilization step. This is because a constant power must be supplied to this sterilization process. Accordingly, the correspondingly large stacks of containers required hitherto to collect these fluctuations can be dispensed with.

Since the concentrate volume emerging from the outlet of the centrifugal drum is only about 10% of the total concentrate volume, it is sufficient for K to branch off a small partial stream from the return conduit in order to generate a constant volumetric flow. be.

Further advantageous developments of the method according to the invention are specified in claim 3 or 4.

A device for carrying out the method according to the invention as well as advantageous embodiments thereof is defined in one of the claims 5 to 9.

An embodiment of the invention is shown in the drawings and will now be described in detail.

〔Example〕

FIG. 1 shows a centrifugal drum at 1, the inlet chamber 2 of which communicates via a passage 3 with a set of separator plates 4, which separates a concentrate chamber 5 in a radial direction. Limit yourself inwardly. From this concentrate chamber 5, a discharge channel 6 with a nozzle T leads to a discharge chamber 8, in which a discharge mechanism 9 is present, and a concentrate outlet 10 of this discharge chamber is connected to a return conduit. Via 11, it communicates with a feed 12 which opens into the inlet chamber 2 of the centrifugal drum 1. A discharge opening 14, which is opened by a piston slide 13, from the drum peripheral wall leads to a collection container 15 for the bacterial concentrate. The return conduit 11 is provided with a regulating mechanism 16 for regulating the amount of bacterial concentrate to be returned. The outlet channel 6 is connected to the drum cover 17 at a distance "A" with respect to this cover in the centrifugal drum 1.
Conical lead-out plate 1 with ribs 19 provided while maintaining the
8. The sterilized milk flows into the outlet chamber 21 through the passage 20, and is then further guided to the outlet 23 by the outlet mechanism 22.

The milk to be sterilized is fed to this centrifugal drum via a feed 12 and flows via an inlet chamber 2 and a passage 3 into a separating plate set 4 in which bacteria are separated from the milk. These bacteria then move to the concentrate chamber 5.

Via the outlet channel 6 and the nozzle 7, a partial stream of the bacteria-poor concentrate is continuously drawn off from the concentrate chamber 5 of the centrifugal drum;
and a discharge mechanism 9, a concentrate outlet 10 and a return conduit 1.
1 to the supply section 12 of the centrifugal drum 1. Bacteria accumulated on the peripheral wall of the drum are periodically transported out of the centrifugal drum 1 via the exit port 14.

A discharge channel 6 with a nozzle 7 extends from the radially central region of the concentrate chamber 5 .

As a result, particularly bacteria-poor concentrate is withdrawn from the concentrate chamber 5, so that the risk of an increase in the number of bacteria in the supply section 12 of the centrifugal drum 1 is avoided.

Distance “A” between drum cover 17 and conical lead-out plate 18
is selected such that at the flow rate of the bacteria-containing concentrate in the outlet channel 6 resulting from this distance, an additional bacterial separation still takes place in this outlet channel. Due to the Coriolis forces acting in the outlet channel 6, a sufficient spacing "A" is necessary regardless of the cross section of this outlet channel 6. This interval “A”
Good results have been obtained when ``A'' is selected in such a way that a throughput of approximately 15 J/h per fl of interval ``A'' is obtained for the individual outlet channels 6.For example, 20
0001/h of milk containing bacteria is supplied, and when 5% of it is drawn out as a bacteria-containing concentrate through the outlet passage 6 formed by eight ribs 19, this outlet passage 61
Nikki; 200001/hxO,05: 8=1 25A'/h
processing power can be obtained.

The value of 151/h is targeted for interval "A" 1n.
The interval "'A" is calculated to be 8.33fl.

By means of the adjustment mechanism 16 of the return conduit 11, the amount of concentrate to be drawn off via the outlet channel can be easily adjusted.

In order to keep the amount of bacteria-containing concentrate produced small, the amount of concentrate discharged via the discharge port must be at most 0.4 to 0.0% of the supply amount.
It is desirable that it is 6 inches.

According to FIG. 2, a post-separation plate 24 is provided between the drum cover 17 and the conical outlet plate 18 in order to achieve a better post-separation of the bacteria.

In the case of the device shown in FIG. 3, a concentrate conduit 36 leads from the return conduit 11 to a merging device 25 for merging the concentrate discharged via this concentrate conduit 36 and the outlet 14. A regulating device 26 is assigned to this merging device 25, which is connected via lines 27, 28 and a control device 29 to the regulating device 16 and to the regulating device 30 in the concentrate line 36. . An adjustable pump 31 is connected to the merging device 25, which pumps the bacterial concentrate from the merging device 25 with a constant output and subsequently pumping it to a sterilization device (not shown).

The partial stream of the bacterial concentrate discharged via the nozzle 7 flows via the concentrate conduit 36 into the combining device 25 in which the concentrate ejected via the outlet 14 is also collected. Ru. Adjustment mechanism 16 depending on the liquid level in the merging device 25.
3G is regulated by the regulating device 26 and the control device 29 in such a way that the liquid level in this merging device 25 remains essentially unchanged. Manual adjustment mechanisms 32,33 can be used to perform the reference amount adjustment. If the liquid level in the merging device 25 drops to an unacceptable degree despite the adjustment mechanism 30 being fully open, the reference volume adjustment of the concentrate conduit 36 is carried out by means of the bypass conduit 35 with the adjustment mechanism 34. can be exceeded. When using adjustment mechanisms 32.33 and 34, adjustment mechanism 16.3 operated by the control device
0 and 34 can be configured as a simple remote-controlled shut-off mechanism, which provides particularly inexpensive adjustment possibilities.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which FIG. 1 is a schematic vertical sectional view of a centrifugal drum, and FIG.
3 shows a circuit diagram of the device for mixing the partial flow from the return conduit with the bacterial concentrate ejected from the outlet. 1. Centrifugal drum, 2. Inlet chamber. , 3...Aisle,
4... Separation plate set, 5... Concentrate chamber, 6... Outlet passage, 7... Nozzle, 8... Outlet chamber, 9... Outlet mechanism, 10... Concentrate outflow Part, 11...Return conduit, 1
2... Supply section, 13... Piston slider, 14.
... Carrying out port, 15... Collection container, 16... Outlet passage, 17... Drum cover, 18... Conical outlet plate, 1
9... Rib, 20... Passage, 21... Lead-out chamber, 2
2... Derivation mechanism, 23... Outflow section, 24... Rear separation plate, 25... Merging device, 27.28... Conductor, 2
9... Control device, 30... Adjustment mechanism, 31... Pump, 32.33.34... Adjustment mechanism, 35... Bypass conduit, 36... Concentrate conduit, A... interval

Claims (1)

[Scope of Claims] 1. A method for centrifugally sterilizing milk, in which milk is supplied to a supply section of a centrifugal drum, and a centrifuged concentrate containing bacteria is accumulated in a concentrate chamber of the centrifugal drum. , a type in which a portion of this concentrate is led out of the centrifugal drum through a lead-out passage equipped with a nozzle, and the remaining concentrate is periodically taken out through a discharge port provided on the outer wall of the drum. A method for centrifugal sterilization of milk, characterized in that the concentrate discharged via the nozzle is withdrawn from the central region of the concentrate chamber and returned to the feed of the centrifugal drum. 2. Dividing the concentrate discharged through the nozzle into two partial streams, returning the first partial stream to the feed of the centrifugal drum, and merging the second partial stream with the concentrate exiting from the outlet; 2. The method as claimed in claim 1, wherein the amount of this second partial stream is adjusted as a function of the amount of concentrate exiting the outlet so that a constant output of concentrate results after this combination. 3. Process according to claim 1 or 2, characterized in that the amount of concentrate drawn off via the nozzle is at most 1-10% of the amount of milk fed via the feed of the centrifugal drum. 4. The amount of concentrate discharged through the discharge port of the centrifugal drum is equal to or less than the amount of milk supplied through the supply section of the centrifugal drum.
．． 4. A method according to any one of claims 1 to 3, wherein the amount is between 1 and 1.0%. 5. An apparatus for carrying out the method according to claim 1, wherein the centrifugal drum (1) comprises a supply section (12) and a separator plate set (4).
), the separator plate set radially inwardly delimiting a concentrate chamber (5), from which a discharge channel (6) with a nozzle (7) as well as a periodic concentrate chamber are provided. A discharge opening (14) for discharge extends, and said nozzle (7) opens into a discharge chamber (8) into which the bacteria-poor concentrate drawn out via said nozzle is deposited. Concentrate outlet (10
), in which said outlet passageway (6) extends from the radially central area of the concentrate chamber (5); and said concentrate outlet (10) is connected via a return conduit (11) to the supply section (1) of the centrifugal drum (1).
An apparatus for centrifugally sterilizing milk, characterized in that it is combined with 2). 6. A concentrate conduit (36) equipped with an adjustment mechanism (30) is branched from the return conduit (11), and the concentrate discharged through this concentrate conduit (36) and the outlet (14) are separated from each other.
A merging device (25) is provided for merging the concentrates drawn off via the The devices (26) are arranged in relation to each other, the regulating device being connected via the conductors (27, 28) and the control device (29) to the regulating mechanism (30) in the concentrate conduit (36) and in the return conduit (11). 6. The device according to claim 5, wherein the device is connected to an adjustment mechanism (16) of. 7. A rib in which the outlet passage (6) is arranged between the drum cover (17) and a conical outlet plate (18) provided in the centrifugal drum at a distance "A" with respect to this drum cover. Claim 5 or 6 formed by (19)
The device described. 8. The distance "A" is 1 m for each individual outlet passageway (6) formed by a rib (19).
8. The device according to claim 7, wherein the device is selected to provide a throughput of 5 to 25 l/h per m. 9. Device according to claim 7 or 8, characterized in that a rear separating plate (24) is provided between the drum cover (17) and the conical outlet plate (18).