DE2160455A1 - centrifuge - Google Patents

Description

Palentanwalt ·

A _vm Drying. HANS RUSCHKE DipK-ing. HfclNZ AGULAR

8 Munich Ti, PienzönauerSir. 2

ii.082.t97i

Alfa-laval AB, S-14 7ÜO Tumba, Sweden

"Centrifuge"

The present invention relates to a centrifugal separator or a centrifuge of the type in which the centrifugal drum has an inlet for a mixture to be separated, a central outlet for a separate light liquid component of the mixture, an outlet on the periphery for separate deposition, this outlet for intermittent Opening is set up, and another, seen radially, located between these outlets Discharge for a separate heavy, liquid component of the Has mixture, where eir. Passage is set up to corridor from the last-mentioned outlet to a receptacle ual to direct for the heavy liquid component.

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209825/0804 BATH ORIGINAL

In a centrifuge of this type, devices are provided for maintaining the interface formed between the light and visual liquid components of the separated mixture within the centrifugal drum at a certain height radially inside the outlet for the heavy liquid component. In their simplest embodiment, these devices can consist of two overflow outlets attached offset from one another in the vicinity of the drum axis of the two liquid components of the mixture. When the separated mixture contains a relatively small amount of the heavy liquid component, a disadvantage with centrifuges of this type is that the space in the centrifugal drum which can be used for effective separation is reduced by the need to have said interface radially inward of the outlet for the heavy liquid component to keep. This creates a less effective separation of the light liquid component, resulting in a shorter flow time in the centrifugal drum. -

In order to avoid that separate, light, liquid components pass the centrifugal drum through the outlet for the heavy liquid component in connection with the fact that AbIa-

203825/0804

Intermittent fermentation through the circumference of the drum is discharged, and thus the mentioned border area radially When it is displaced outwards, it is common to only see heavy, liquid components of the drum during a short period of time either before the perimeter outlet is opened, or immediately after this outlet has been opened and closed again. The need for such operations in connection with deposit emptying is also a specialist part of centrifuges of this type.

The object of the present invention is to provide those described above. To remove roof parts and firstly to equip centrifuges of this type with devices that are set up in such a way that they steep the fluid flow to said recording for heavy liquid components through the specified through-

either

let ^v allow or prevent, and secondly with devices which are set up so that they indicate when there is separated heavy, liquid component at a predetermined height in the centrifugal drum, and which then influence said first devices so that liquid flow to the receiving part is allowed through the passage.

In such an arrangement, maintenance proves itself

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BATH ORIGINAL

an interface between light and heavy liquid components radially within a certain height in the drum than no longer necessary. It can be allowed that the interface also radially outside of the drum outlet for the heavy liquid component rises without thereby light liquid component is lost.

In centrifuges of the type under consideration, the circumference is off often have the drum set up so that it is opened at regular intervals. The time between two openings is then determined by the estimated deposit content of the mixture to be separated. However, the deposit content remains seldom during the entire separation process' constant and can change within very wide limits. Sometimes it happens that between two opening processes so much sediment is separated in the drum that the so-called plate washer set in the drum is clogged, which necessarily entails the shutdown of the centrifuge and its manual cleaning.

For this reason, it is desirable to keep the time between two opening processes as short as possible. For other reasons, however, it is again desirable not to allow too short periods of time between the opening processes

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reach. In this case, the opening mechanism is worn to an undesirable extent. Furthermore, the separation is disturbed each time it is opened. '.

With a centrifuge according to the invention it is possible the clogging of the flare disk set with a high deposit content of the mixture to be separated without the above mentioned Avoid disadvantages. Therefore the mentioned perceptual or discharge device arranged to provide a necessary for opening the peripheral outlet a of the drum Signal generated as soon as a heavy liquid component arrives the predetermined height or level is perceived in the drum o The drum circumferential outlet then opens not immediately after expiry of a preset intermediate period, if not during this period also separate deposition the interface between lighter and heavier liquid component of the separated mixtures after urged inside to the predetermined level in the drum Has. If the ratio of the quantities of light and the heavy liquid component remains essentially unchanged, as a result of which the period of time between the opening processes automatically longer at a low than with a high level of deposit in the separate mixture. Another advantage of this arrangement is that the

209625/0604

opening outlet of the drum is only opened when the interface between the light and heavy liquid components within a certain height or level which means that loss of the lighter liquid component through the circumferential outlet can be avoided. that separate deposits in the drum pack too tightly together, during said periods of time, which would be long if the separated mixture were a relatively If it contained small amount of sediment and heavier, liquid component, it is possible to use the drum with a certain additional amount of heavier liquid component either intermittently or continuously during the To fill the separation process, so that the periods of time are shortened.

In the centrifuge according to the invention, said perception s device set up to indicate when separate heavy liquid components are located at a predetermined height in the centrifugal drum, either devices for perceiving or sensing a difference between a light liquid component and a heavier liquid component Component, e.g. B. a difference in. Their dielectric constants, or devices for comparing the liquid

209825/0004

_ 7 -

pressure at a certain distance from the drum axis on the one hand in the separation chamber of the drum and on the other hand in a connection that extends from a Point radially outside the predetermined height in the drum separation chamber inwards in the direction of the drum axis extends.

When using devices of the first-mentioned type, it is ensured that a flow of liquid to the receiving point for heavy liquid components also arises when through after the drum is completely emptied their circumferential outlet the inflowing mixture only from heavier liquid component and deposit. In such cases, a desired ad cannot be matched with a Pressure comparison device can be achieved. If such cases are excluded, however, a pressure comparison device can be used use very well. Then it is sufficient, namely, the central outlet of the drum for the light liquid component to form as an overflow outlet, which then serves as a means for maintaining a constant liquid pressure in the drum at this outlet regardless of the continuous Plüssigfluss is used, and a pressure sensing instrument to connect to the above connection inside the drum. This pressure perception instrument can be used for direct

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th display of the pressure difference can be set on their Basis of a liquid flow to the receiving parts for heavy liquid component should arise.

When a sensing device is used which is arranged to indicate a difference between two liquids is, the centrifuge preferably comprises one of the predetermined height in the drum outgoing channel and a device for generating a liquid flow through this channel from a predetermined height of the drum, the perception device for indicating a change the liquid flowing through the channel is established. In an arrangement of this type, the sensing device need not rotate with the drum. the Perception device can, for example, be set up in such a way that it changes the flowing liquid with respect to their viscosity, density, electrical conductivity, etc. Various optical measuring methods can also be used be applied.

In a preferred embodiment of the invention, the Canal and the aforementioned passage at least partially the same course. Furthermore, the channel preferably opens into the feed line of the drum for the mixture to be separated,

209825/0804

with a constant fluid circulation through a outside the drum. Perception instrument can be achieved through.

Within the R _a of the invention hmens there is the possibility a ^ ¹ IUs sigke it sfluß in certain time intervals from the predetermined level in the drum to the receiving position for heavy liquid component allow and then perceive whether these liquid light or heavy liquid component of the If a heavy liquid component is then sensed, the device controlling the intermittent flow can be switched off and a continuous flow can be allowed, ie a flow which lasts as long as it is necessary. The invention is further described below with reference to the drawing. In this show *

Fig. 1i is a cross section through a centrifugal drum Centrifuge according to the invention *

Fig. 2i is a flow sheet in which the centrifuge is a part represents} and

3t shows a schematic representation of a perception device.

209825/0304 - 10 -.

- ίο -

The centrifugal drum according to FIG. 1 comprises a lower part 1 and an upper part 2 which are held together by a locking ring 3. The drum is on a drive shaft 4 stored, which has a central channel 5 for feeding the mixture to be separated into the drum. The mixture is supplied by a distributor provided with pick-up elements 6 7 passed into the drum separation chamber 8, wherein a set of conical Discs or Te 11erscheiben 9 is arranged. Deposit, separated from the mixture fed to the drum

is, is collected at 10 in the separation chamber 8. For the intermittent emptying of this deposit during operation of the centrifuge, the drum has a number of openings 11 on its circumference. A valve disk 12, which forms the bottom of the separation chamber 8, is arranged in such a way that it opens and closes the openings 11. The valve disk 12 can be actuated in a known manner by means of a liquid which is fed to its underside through a feed element 13 surrounding the drive shaft 4. When the liquid is fed to a space 14 located between the lower part 1 of the drum and the valve disk 12, the valve disk 12 is held in its upper position in which it is pressed against the upper part 2 of the drum. Aue the space in between

14 liquid flows through narrowed or throttled openings

15 in the drum part 1. If the liquid supply to the

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209825/0804

Intermediate space 14 interrupted, then this intermediate space is emptied of liquid through the opening 15, the valve disk then being pressed down by the liquid pressure in the separating chamber 8, so that the openings 11 are released. Will the hydration in the ^ Mfim ¹ ^? resumed, the valve disk 12 is pressed up again so that the openings 11 are closed.

Liquid component, which is separated from the mixture fed to the drum, leaves the separation chamber 8 through a central overflow outlet 16 and then flows into a chamber 17 · By means of a peeling disk 18 arranged in this chamber, the separated liquid component further pumped out through an outlet line 19.

From the radially outer part of the drum separation chamber 8, i. H., in the area of the outer edges of the plate washers 9, extends A channel 20 extends inwards towards the drum axis up to a chamber 21 located there. Inside the chamber 21 is a peeling disk 22 for pumping out liquid. from the chamber through a conduit 23, which is thus a continuation of the channel 20 forms. The liquid flowing through the channel into the chamber 21 passes on its way

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209825/0804

21604S5

a tibeilaüfauölaß 24. "' ^v > - ·; ^ ν.,; .-, .-

2? Ig> 2 centrifuge S t shown a Schleudertrommei described above. Type has »A feed line for the mixture to be separated in the drum is designated 25 * This feed line: is connected to the channel 5 located in the drum drive shaft 4 (JPig. 1).

Accumulation separated from the Gemiaeh is discharged through a conduit 26, while separated light liquid component through the line 19 and separated heavy liquid Component are discharged through line 23.

From the line 23 another line continues 27, which is connected to the inlet line 25 for mixture to be separated "In the conduit 27 there is a throttle device 28 and seen behind this in direction of liquid flow through the conduit * i ^s" fe a shut - Or check valve 29 is arranged, * which opens only when a certain..iquid pressure is reached in the line.

Me device 30 ifirfc for the perception of the dielectric constant of the liquid flowing through the line 23 is set up It is furthermore set up to:

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a valve 32 to the perceived value of the dielectric constant of the liquid via a connection 31 press, which is in line 23 behind the point, where the line 27 begins. By means of a connection 33, the perception device 30 is also designed so that the control device of the centrifuge for the purpose of release and closing of the deposit outlet openings located on the drum periphery. This control device, in the drawing denoted by 34, is arranged in such a way that it can be used in certain periods of time, which are long with reference to the estimated Deposit content in the mixture to be separated has been determined, an actuation for the purpose of opening the deposit outlet openings 11 introduces.

In addition to the line 27, a line 35 is connected to the feed line 25 for the mixture to be separated in the drum, around the drum an extra amount of heavier, more liquid Feed component. A pump 36 is arranged in the line 35.

In Pig. 3 are part of the line 23 and the device for sensing the dielectric constant of the liquid flowing through the line 23. The device includes a perception element 37 and thus a connection

-H-209825/0804

Binding 38 connected display instrument 39. The display instrument, which is connected on the one hand to a power source 40 and on the other hand via a connection 41 to a line 23, comprises an oscillator not shown in the drawing. Devices of this type are known and do not require any further description.

The operation of the centrifuge described above is like follows 1

Through the line 25 and the channel 5 located in the drum drive shaft 4, the centrifugal drum is filled with a mixture consisting of a light liquid component such. B., oil, a heavy liquid component, e.g. B «, water, and a deposit, the density of which is greater than that of the two liquid components. In the drum separate deposit is in this We ise at Trorame! Extensive collected and an interface between the light and heavy liquid component is formed between the opening of the channel 20 in the separating chamber 8 and the drum circumference 1.1. "Separate light liquid component leaves then the Tromme The oil separation chamber on the one hand through the central overflow outlet 16 and on the other hand through the channel 20 via the overflow outlet 24. While liquid flowing into the chamber 17

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, ^ rmc ; 20982 5/0804

enters through overflow outlet 16, through line 19 by means of the peeling disk 18 to a receiving point for separate light liquid component is pumped, liquid will enter the chamber 21 through an overflow outlet 24 enters, pumped out through the line 23 by means of the paring disc 22 and through the line 27 to the inlet line 25 pumped back for the mixture to be separated. The valve 32 is closed in the initial position.

During the separation there will be more and more deposits and heaviness liquid component collected in the drum separation chamber. the The interface between the light and heavy liquid component is thus moved radially inward and gradually reached a height or level at the opening of the duct .20 in the Trenhkamaier 8. In Fig. 1, this height is indicated by a dashed line Line 42 shown. Instead of the separate light liquid component, separate heavy liquid now begins Component through the channel 20, the chamber 21, the paring disc 22 and / to flow line 23. This is done by the perception device 30 perceived, which then the valve 32 actuated so that it is opened · The separated liquid component does not get back through the line 27 to the inlet line 25 but continues to flow through the line.

■ '. \ - 16 -20 9825/0804 BAD ORIGINAL

device 23 to a receiving point for heavy liquid components. This receiving point, not shown in the drawing, can be a container or an outlet opening the valve 32 decreases the fluid pressure in the line 27 »whereby the shut-off or check valve 29 is automatically closed.

Simultaneously with the actuation of the valve 32 by the sensing device 30, the latter sends to the centrifuge control device 34 given a signal without this device taking an action to open the drum circumferential outlet 11 cannot cause .. thus has the interface in the drum between light and heavy liquid components the opening of the channel 20 has not yet been reached if a period of time predetermined for the control device for the opening of the circumferential outlet 11 has passed, the can Circumferential outlet 11 cannot be opened. Only if the Perception device 30 in the line 23 perceives heavy liquid components, the control device 34 receives the signal necessary to open this outlet. To avoid long periods of time between opening processes the circumferential outlet is opened if there is a risk of

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825/0 804

By packing of deposits on the drum, the centrifugal drum is preferably continuously or intermittently with a small additional amount of heavy liquid component means the pump 36 through the line 35 and the inlet line 25 is charged. However, it reaches the interface between lighter and heavier liquid component the opening of the channel 20 before the time period set for opening the circumferential outlet 11 has expired, then the separation will continue until the period of time has passed, the interface then at the level 42 shown in FIG. 1 remains. Through the overflow outlet 24, the interface is prevented from moving back radially outward during separation. These Effect could also be achieved without an overflow outlet, if so the valve 32 in the line 23 is a so-called constant pressure valve, that is, a valve with automatically controllable transfer capacity so that the pressure in line 23 is independent the size of the river flowing through it on one would be held at a predetermined value.

Practice it was assumed that the sensing device is of the type that it can sense a change in the fluid flowing through the line 23. The Yv ^{r a} perception

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209825/0004

direction 30 can, however, also be a pressure sensing device that is connected and set up so that it can handle the Detects pressure in channel 20. At the one shown in the drawing Embodiment speaks of the pressure in the line 23 due to the Droseelungsvorrichtung 28, which the flow through the lines 23 and 27 limited, directly to the pressure in the channel 20. A certain pressure or pressure change in the line 23 can be used as an indication that the interface between the light and heavy liquid components has moved radially inward to a certain level, which on the one hand sends a signal to the valve 32, which is for the to open separate heavy liquid component, and on the other hand to the control device 34 has the consequence, so that Deposits can be emptied through the peripheral outlet 11.

If the liquid pressure in the channel 20 is used as a characteristic for the position of the interface between lighter and heavier liquid Component selected in the spin drum then needs a circulation, as described above, necessarily no longer be provided. The line 27 can thus be omitted will. The pressure in channel 20 can be sensed or sensed in many different ways, for example by pumping in of air at a suitable height below that in the chamber

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formed liquid surface and by measuring a Change in resistance as a result of this air supply. The overflow outlet 24 is not required.

The line 27 can also be omitted when in use a perception device for direct perception the said interface is set up in the drum. A perception device of this type can be attached to the drum and rotate with it.

Further modifications can be made within the scope of the invention. Thus, the sensing device 30 can comprise both devices for sensing a difference between two liquids and devices for sensing a change in pressure in the drum, the valve 32 in the line 23 being set up so that it does not open until a predetermined pressure and heavy liquid components are perceived by the perception device »Two or more connections with different absorption capacities between the channel 20 in the drum and the receiving point for heavy liquid components can also be used, e.g. B. ₄ a connection with a relatively low capacity, which is set up so

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that it opens upon the perception of heavy, liquid components in the line 23, and a second connection with greater absorption capacity, which only opens when the pressure in the line has risen to a certain value after an occasional drop is. With such an arrangement, the controller 34 of the centrifuge can also be set up so that the drum circumferential outlet in the case of information from the perception device, that both heavy, liquid components and a certain pressure in line 23 are perceived, is opened, even if a for the control device predetermined period of time between two opening processes has not yet expired. The one for such information The pressure required to the control device should be higher than the pressure required to open the connection mentioned with greater absorption capacity to the receiving point for heavy liquid component is required. This consequently avoids that heavy liquid components through the central outlet of the drum for light liquid component drains in case of failure of the valves in the connections occur at the receiving point for heavy liquid components would. The valve 32 can of course also be through a three-way valve at the point at which the line 27 begins on the line 23, or by any suitable arrangement.

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the to liquid flow through line 23 to the receptacle ateHe'für * to prevent heavy fluids or components to allow. "

20 9 8 2B / Q80

Claims (13)

- Patonfanwfilf Jl Drying. HANS RUSCHKE DIP. HEINZ AGULAR I MOd PienzenauerSfr. Claims i1.) Centrifuge, the centrifugal drum of which has an inlet for a mixture to be separated, a central outlet for a separate light liquid component of the mixture B ₉ an outlet arranged on the periphery for separate deposits, which is set up to be opened intermittently during operation, and for a separate heavy liquid component of the mixture having a further outlet located between the first-mentioned outlets, a thermosetting passage being arranged to convey liquid from the latter-mentioned outlet to a receiving point for heavy liquid components, characterized by a device (32) which is arranged to flow liquid to the receiving point for heavy liquid; component through said passage (20, 21, 23). either to allow or to prevent, and a device (30) arranged to sense when they broke up - 2- 209825/08 (K heavy liquid component at a predetermined Height or level (42) is located in the centrifugal drum, and then actuate the device (50) so that liquid s flow to the receiving point through the passage (20, 21, 23). 2. Centrifuge according to claim 1, characterized in that said device (32) is a valve in the passage (20, 21, 23). 3. Centrifuge according to claim 1 or 2, characterized in that said perception or sensing device (30) is set up to generate a signal required to open the drum circumferential outlet (11), wan bi the predetermined height or level (42 ) a heavy liquid component is perceived in the drum. 4. Centrifuge according to one of claims 1 to 3, characterized in that the Yiahrnehmungseinrlchtung (30) has devices for comparing the liquid pressures at a certain distance from the drum axis on the one hand Ih the drum separation chamber (8) and on the other hand in a connection (20) from a point in the drum separation chamber radially outside of the predetermined one - 3 209825/0804 Height or level (42) extends to the drum axis. 5. Centrifuge according to claim 4, characterized by a device (16) which is arranged in the central outlet for light liquid components and is arranged so that it keeps the liquid pressure in the drum constant at this outlet regardless of the liquid flow flowing through it, wherein the pressure comparison device is formed by a pressure sensing instrument (30) connected to said connection. 6. Centrifuge according to one of claims 1 to 3, characterized in that the Yfahrnehmungseinrichtung (30) comprises devices (37-41) which are set up for perceiving a difference between a light liquid component and a heavy liquid component, for example a difference in their dielectric constant are. 7. Centrifuge according to claim 6, characterized by a channel (20, 21, 23, 27) which extends from a point at or radially within the predetermined height or level (42), and by a device (22) for generating a liquid flow through the channel from this point in the centrifugal drum, whereby the perceptual _ 4 _ 209825 / 080A - ever - devices (37-41) for perceiving a change in the liquid flowing through the channel (20, 21, 23, 27) are arranged. 8. Centrifuge according to claim 7, characterized in that the channel (20, 21, 23, 27) and the passage (20, 21, 23) have at least partially the same course » 9. Centrifuge according to claim 7 or 8, characterized in that the channel (20, 21, 23, 27) opens into the feed line (25) for the mixture to be separated. 10. Centrifuge according to one of claims 7 to 9, characterized by a device (29) for blocking the liquid 'Keitsflusses through the channel (20, 21, 23, 27) when the Liquid flow through the passage (20, 21, 23) to the mentioned recording point has started. 11.. Centrifuge according to one of Claims 8 to 10, characterized characterized in that the passage (20, 21, 23) and the. . Channel (20, 21, 23, 27) in front of a branch point, seen in the direction of flow of the liquid - gemslnsanien .Verlauf have, and that a valve (29) arranged behind the branch point is set up around the channel only 209 _ 5 _ ORIGINAL BATHROOM Room to be kept open when a predetermined minimum pressure foresees in the anal. 12. Centrifuge according to one of the preceding claims, characterized in that the perception device (30) has both perception devices according to claim 4 or 5, and perception devices (37-41) according to claim 6 or 7, and that said device (32) by this sensing device is operable so that no liquid flow through the passage (20, 21, 23) to the receiving point is allowed before both a predetermined pressure and heavy liquid component are sensed by the corresponding sensing device. 13. Centrifuge according to one of claims 7 to 12, characterized by a throttling device (28) in the channel (20, 21, 23, 27), an outlet arranged in front of the throttling device with a greater capacity than the throttling device in the outlet arranged shut-off valve (32), and through a with the channel (20, 21, 23, 27) connected to the throttle device (28) pressure sensing device (30), which is arranged so that when sensing a predetermined pressure in the - 6 209825/0804 Channel the shut-off valve (32) to open the outlet is operated. 209825/08 (U