CN211713509U - Pumping screen and pumping screening system - Google Patents
Pumping screen and pumping screening system Download PDFInfo
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- CN211713509U CN211713509U CN202020271533.4U CN202020271533U CN211713509U CN 211713509 U CN211713509 U CN 211713509U CN 202020271533 U CN202020271533 U CN 202020271533U CN 211713509 U CN211713509 U CN 211713509U
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Abstract
The utility model relates to a pumping sieve, this pumping sieve includes: a pump housing; a rotor wheel housed within the pump housing; a drive shaft that rotatably drives the rotor wheel through the pump housing; the pump inlet of the pump shell is opposite to the front face of the rotor impeller, the pump outlet is located on the peripheral side face of the pump shell, the pumping sieve further comprises a pulp sieve, the pulp sieve divides the pump shell into a centrifugal cavity and a screening cavity, the centrifugal cavity contains the rotor impeller, and the screening cavity is provided with a good pulp outlet. The utility model also provides a pump sending screening system.
Description
Technical Field
The utility model relates to a pump sending sieve, this pump sending sieve especially are used for pulping papermaking field. The utility model discloses still have a screening system with the pump sending sieve.
Background
The pressure screen is the main equipment of the pulping process in the paper industry.
In the current papermaking production line, the pressure sieve for pulp screening is generally required to be higher than 1-3kg/cm2The inlet pressure of the pressure screen ensures that the pressure screen operates normally and effectively under pressure, since the pulp fluid with a certain pressure makes the screening area between the screen plate and the rotorThe area is provided with required pressure, and the pressure of the inlet also ensures that the liquid in the pressure screen is in a full state.
A small gap is formed between the rotor blade of the pressure screen and the screen cylinder to ensure that the rotor blade does not contact the screen plate, and simultaneously, fluid disturbance generated by the movement of the blade relative to the screen plate acts on the screen plate, and the gap is usually adjustable. During the rotation process of the pressure screen rotor, pressure pulse is generated on the slurry through the movement of the rotor blades along the surface of the screen cylinder, so that the pressure difference inside and outside the screen plate is increased, and the slurry is accelerated to pass through the screen plate; the pressure of the blades to the pulp is reduced along with the gradual increase of the gap between the tail parts of the blades and the screen drum, a local low-pressure area appears in the area, when the absolute value of the pressure of the pulp inside and outside the screen plate is equal in the low-pressure area, the pulp stops sieving, when the negative pressure is continuously increased, the water and partial pulp in the good pulp outside the screen plate return through the screen plate, the effect of backwashing pulp clusters and long fiber impurities on the screen plate is achieved, and therefore the continuous normal operation of the pressure screen is guaranteed.
The pressures required to operate various pressure screens almost exclusively originate from centrifugal pumps arranged in the system before the screen. It is even believed that the screening process of the pressure screen is accomplished by both the screen and the centrifugal pump.
Because the pressure screen and the centrifugal pump are both provided with rotors, the normal and effective operation of the pressure screen requires that the pressure is not lower than a certain pressure range, usually 2kg/cm2The upper and lower ranges are wide. Typically, the linear speed of the rotor of a centrifugal pump, where the pressure screen provides pressure, is close to the linear speed of the pressure screen rotor.
In centrifugal pumps, a pump casing is filled with liquid and an impeller rotates at high speed within the pump casing to create centrifugal force. The liquid is thrown to the periphery of the impeller at high speed under the action of centrifugal force. In the process that liquid flows from the inlet to the outlet of the impeller, the speed of the liquid is reduced through the gradually enlarged pump shell channel, the pressure is increased, and the dynamic pressure head is converted into the static pressure head.
In the prior art, a centrifugal pump and a pressure screen are two independent process devices and are connected through a pipeline.
Disclosure of Invention
The utility model provides a pumping sieve, this pumping sieve combine into pressure sieve itself with the pressure boost function of centrifugal pump to realize pressure screening under the condition of not using independent pumping, thereby simplify the process, investment costs such as saving equipment pipeline valve and factory building space reduce consumption of power.
The utility model discloses a pumping sieve includes: a pump housing; a rotor wheel housed within the pump housing; a drive shaft that rotatably drives the rotor wheel through the pump housing; the pump inlet of the pump shell is opposite to the front surface of the rotor impeller, and the pump outlet is positioned on the peripheral side surface of the pump shell; the pumping sieve also comprises a pulp sieve, wherein the pulp sieve divides the pump shell into a centrifugal cavity and a screening cavity, the centrifugal cavity contains the rotor impeller, and the screening cavity is provided with a good pulp outlet.
The utility model provides an in the pumping sieve, integrate two kinds of rotors of centrifugal pump and pressurized screen on a rotor, make the ability of the existing pumping of this equipment, can improve pressure, also have the screening function.
The utility model provides an in the pumping sieve, the screening function integration together of the pumping pressure boost function of centrifugal pump and pressurized screen only need will the utility model discloses a pumping sieve arranges storage facilities next door such as tank to ensure that the minimum liquid level in the tank is higher than the position of the entry of pumping sieve, after the start-up, the pumping sieve will provide required screening pressure for the work operation of self.
According to a preferred embodiment of the pumping screen of the present invention, the paddle screen is a screen plate that is fixed to the pump housing or integrally formed on the pump housing at the back side of the rotor impeller, the screen holes of the screen plate are only provided in the radially outer region of the paddle screen, and the central region of the paddle screen is not provided with screen holes.
The sieve plate can be in a plane shape, or in a funnel shape with the center being retracted into the screening cavity, or in a cone shape with the center being raised towards the centrifugal cavity.
According to another preferred embodiment of the pumping screen of the present invention, the pulp screen is a hollow structure fixed to or integrally formed on the pump housing at the back side of the rotor impeller, and at least a part of the area of the peripheral side wall of the hollow structure is a screen plate; the rotor impeller has a bend around the hollow structure at a radial outer periphery, the bend divides the rotor impeller into a centrifugal impeller portion near the drive shaft and a screening impeller portion near the distal end, a back side of the screening impeller portion of the rotor impeller being opposite to the screen plate.
The rotor wheel may be bent at a radial outer periphery thereof toward a back side of the rotor wheel, or the rotor wheel may be bent at a radial outer periphery thereof toward a front side of the rotor wheel.
Preferably, the hollow structure is in a circular truncated cone shape, the top surface of the circular truncated cone is opposite to the back side of the rotor impeller, and the outer peripheral side wall of the circular truncated cone forms the sieve plate.
Preferably, the hollow structure is cylindrical, a top surface of the cylinder is opposite to a back side of the rotor impeller, and an outer peripheral side wall of the cylinder forms the sieve plate.
The peripheral side wall of the hollow structure may be curved.
The pumping sieve provided by the utility model has the same installation position as a common centrifugal slurry pump and is arranged beside a slurry pool or a water pool, so that the height of an inlet is ensured to be below the liquid level of the slurry pool or the water pool; the same as a common centrifugal pump, the utility model discloses a central line design of inlet pipe of pumping sieve and the central line of rotor is coaxial linking, and thick liquids flow into the casing of pumping sieve with the help of the liquid level static pressure in the thick liquid pond before the pump or white water pond and the suction force that "pumping sieve" rotor produced (the vortex low pressure effect at impeller center), reach the pumping region, reach the screening region after certain linear velocity (according to pressure needs, usually in 10-30m/s scope) through the pumping blade acceleration, have 1-3kg/cm thick liquids in the screening region2The pressure of (a).
When thick liquids get into the utility model discloses a behind the pumping sieve, at first have the centrifugation part of function with higher speed on the contact rotor, thick liquids are accelerated to certain linear velocity by the blade of rotor and are made the thick liquids fluid have sufficient dynamic pressure head, and the thick liquids that later possesses pressure reachs the screening region of compriseing sieve mesh (or screen cut) and rotor, do not have the centrifugation blade with higher speed in this screening region, therefore the same with the centrifugal pump principle, fluidic speed converts pressure into, carries out pressure screening in this region.
The pulp passing through the screen holes or screen slits in the screening area enters a good pulp chamber, and the pulp passes through a screen plate although the pressure is reduced to a certain extent (usually, the pressure is only 0.1-0.5 kg/cm)2) But still with sufficient pressure by which the accept is conveyed to the next process and possibly even to the thickener located highest in the plant. Tailings slurry that does not pass through the screen deck also exits the apparatus under the pressure of the screening zone and is sent to the next process or discharge system.
Therefore, the pressure required by the screening area of the pumping screen is provided by the rotor of the pumping screen, and tailings with pressure after screening can be discharged to other processes.
Compare with the pressurized screen among the prior art, the utility model provides a pumping sieve installation requirement is simple, and area is little, has saved equipment and pipeline investment cost, has reduced the loss of pressure of pumping process, and power consumption also can reduce.
The utility model discloses a one of the most advantageous application of pump sending sieve sets up this pump sending sieve between the pulper of the low dense pulping system of waste paper pulping papermaking trade and the clear miscellaneous machine of water conservancy, can improve the pulper's the ability of disintegrating and clear miscellaneous quick-witted sediment ability of water conservancy simultaneously.
Use the utility model discloses an another advantage of pumping sieve is that the good thick liquid that the pressure tailings of taking of pumping sieve can ensure the clear miscellaneous machine of water conservancy has sufficient pressure to the concentration of having avoided the clear sediment machine of water conservancy is low, perhaps the good thick liquid of intermittent type emission returns to the pump of unloading of pulper, has also avoided the pump of unloading to present the emission of periodic concentration low valley value, finally makes the continuation of good thick liquid concentration and flow stable work in succession of the pump of unloading.
Use the utility model discloses a behind the pumping filter, the good thick liquid of "pumping filter" can discharge with arranging the sediment by the continuous type, and the thick liquids mixture that comes by the pulper cell body passes through earlier the utility model discloses a pump sending sieve handles the back, sends into the clear sediment machine again, and the fibre of having discongested in the thick liquids passes through the utility model discloses a pump sending sieve carries out the continuous separation, makes the part that should not get into hydraulic clear sediment machine originally (the fibre of having discongested) discharge by the pump of unloading in succession partly to there is an extra good thick liquids output. The fiber proportion of the mixed material entering the hydraulic impurity removing machine is reduced, the total amount is correspondingly reduced, and the capacity of the hydraulic impurity removing machine is correspondingly improved. This allows the functions of both hydropulper and hydrotrash remover to be improved by increasing the separation of primary fibers from the paper and debris.
The utility model provides a pumping sieve only requires for inlet pressure, and sediment department has the pressure of 2 ~ 5 meters to promote, in addition, because the good thick liquid discharges in succession and installs the pump of unloading at lower position, consequently, the good thick liquid needn't have pressure, and is comparatively simple in the concrete implementation.
The utility model also provides a screening system, this screening system include thick liquids pond, thick liquid sediment pond and good thick liquids pond, still include above the pump sending sieve, the pump entry of this pump sending sieve directly with the thick liquids pond is linked together so that extract thick liquids, and the pump export is linked together with thick liquids sediment pond, and the good thick liquids export then is linked together with good thick liquids pond.
Drawings
FIG. 1 illustrates a prior art pump and individual pressure screen arrangement;
FIG. 2 illustrates the arrangement of the pumping screen of the present invention during the slurry screening process;
fig. 3A to 3C illustrate a preferred embodiment of the pumping screen of the present invention, in which various screen deck forms are shown;
fig. 4A to 4D illustrate a preferred embodiment of the pumping screen of the invention, in which a pulp screen and a bent rotor wheel in the form of various hollow structures are shown.
In the figures, identical or similar features have identical reference numerals.
Detailed Description
Fig. 1 shows a single pressure screen arrangement in the prior art, as shown in fig. 1, a slurry pump 102 is arranged at the rear end of a slurry inlet tank 101, the slurry pump 102 feeds pressurized slurry into a pressure screen 103, and the slurry is fed into a slurry tank 104 and a good pulp tank 105 respectively after being screened.
The slurry pump and the pressure screen are respectively arranged in the slurry screening system as two independent devices, so that the installation is complex, the occupied area is large, and the energy consumption is increased in the actual production due to potential energy generated by the height difference between the two devices.
Fig. 2 illustrates the arrangement of the pumping sieve in the slurry screening process, as shown in fig. 2, it can be seen clearly that the pumping sieve 200 provided by the present invention integrates the centrifugal pump and the pressure sieve together, so that the equipment has the pumping capacity and the screening function.
The utility model provides an in the pumping sieve 200, the screening function integration together of the pumping pressure boost function of centrifugal pump and pressurized screen only need will the utility model discloses a pumping sieve is arranged and is being advanced storage facilities next door such as thick liquid pond 101 or tank to ensure to advance the position that the minimum liquid level in thick liquid pond 101 or the tank is higher than the entry of pumping sieve 200, start-up back, pumping sieve 200 will provide required screening pressure for the work operation of self.
After being screened by the pumping screen 100, the slurry is sent to a slurry tank 104 and an accept tank 105, respectively.
Fig. 3A to 3C illustrate a preferred embodiment of the pumping screen of the present invention, and as shown in fig. 3A to 3C, the pumping screen 200 of the present invention includes: a pump housing 210; a rotor impeller 220, the rotor impeller 220 being housed within the pump casing 210; a drive shaft 230, the drive shaft 230 rotatably driving the rotor impeller 220 through the pump casing 210; wherein, the pump inlet 240 of the pump casing 210 is opposite to the front face of the rotor impeller 220, and the pump outlet 250 is located at the peripheral side face of the pump casing 210; the pumping screen 200 further comprises a screen 260, the screen 260 dividing the pump housing 210 into a centrifugal chamber 270 and a screening chamber 280, the centrifugal chamber 270 accommodating the rotor wheel 220 and the screening chamber 280 having a accepts outlet 290.
Among these, the screen 260 is a screen plate fixed to or integrally formed with the pump housing 210 on the back side of the rotor impeller 220.
Wherein fig. 3A shows the screening deck 260 of the pumping screen 200 as being planar; fig. 3B shows the screening deck 260 of pumping screen 200 in the shape of a cone with a center that is convex towards the centrifugal chamber 270, and fig. 3C shows the screening deck 260 of pumping screen 200 in the shape of a funnel with a center that is indented into the screening chamber.
From the various views, it can also be seen that in fig. 3A, 3B, 3C, the screening deck 260 of pumping screen 200 has screening holes only in the radially outer regions of screening deck 260 and no screening holes are provided in the central region of screening deck 260.
Fig. 4A to 4D illustrate several modified structures of the paddle screen and the rotor impeller in the pumping screen of the present invention, and as shown in fig. 4A to 4D, the paddle screen 260 of the pumping screen 200 is a hollow structure fixed to or integrally formed on the pump housing 210 at the back side of the rotor impeller 220, and at least a part of the region of the peripheral side wall of the hollow structure is a screen plate; the rotor impeller 220 has a bend around the hollow structure at the radial periphery, the bend dividing the rotor impeller into a centrifugal impeller portion near the drive shaft and a screening impeller portion near the distal end, the back side of the screening impeller portion of the rotor impeller 220 being opposite the screen deck.
Both the planar screen decks of fig. 3A to 3C and the screen decks shown in fig. 4A to 4D arranged as at least a partial region of the peripheral side wall of the hollow structure have the screen openings arranged in a radially outer region. For a planar screening deck, the screening holes are arranged in a radially outer region of the screening deck; for the sieve openings on the peripheral side wall of the hollow structure, the sieve openings are arranged on the peripheral side wall and thus also in the radially outer region.
In fig. 4A and 4B, the hollow structure in which the back side of the rotor impeller 220 is fixed to or integrally formed with the pump housing 210 has a cylindrical shape, the top surface of the cylinder is opposed to the back side of the rotor impeller, and the outer peripheral wall of the cylinder forms the screen plate.
In fig. 4C and 4D, the hollow structure in which the back side of the rotor impeller 220 is fixed to or integrally formed with the pump housing 210 has a circular truncated cone shape, the top surface of the circular truncated cone faces the back side of the rotor impeller, and the outer peripheral wall of the circular truncated cone forms the screen plate.
In fig. 4A and 4D, the rotor wheel 220 is bent radially outward toward the back side of the rotor wheel 220,
in fig. 4B and 4C, the rotor wheel 220 is bent radially outward toward the front face of the rotor wheel 220.
Further, it should be understood that the screen panels that form the peripheral side walls of the hollow structure of the shaker 260 may also be curved.
In addition, it is easily understood that, in the hollow structure-like pulp screen shown in fig. 4A to 4D, while the radially inner most region of the cylindrical top surface or the circular truncated cone top surface of the pulp screen is kept free of screen holes to achieve the pumping function of the pumping screen according to the present invention, the radially outermost region of the cylindrical top surface or the circular truncated cone top surface is allowed to have screen holes, although this is not a preferred embodiment. Since, in contrast to the planar screen deck in fig. 3A to 3C, it is also possible to arrange the screen openings in the radially outermost region of the cylindrical or circular truncated cone top surface.
In the above drawings, different embodiments of the pumping screen 200 are illustrated, and it can be seen that the pumping screen 200 integrates the pumping and pressurizing function of the centrifugal pump and the screening function of the pressure screen in the prior art, so that the installation requirement is simple, the floor area is small, the investment cost of equipment and pipelines is saved, the pressure loss in the pumping process is reduced, and the power consumption is also reduced.
The foregoing describes preferred embodiments of the present invention, but the spirit and scope of the present invention is not limited to the specific disclosure herein. Those skilled in the art can freely combine and expand the above embodiments in accordance with the teachings of the present invention to make further embodiments and applications within the spirit and scope of the present invention. The spirit and scope of the present invention are not to be limited by the specific embodiments but by the appended claims.
Reference numerals
101 slurry inlet tank
102 slurry pump
103 pressure screen
104 slurry pool
105 good pulp pond
200 pumping sieve
210 pump casing
220 rotor impeller
230 drive shaft
240 pump inlet
250 pump outlet
260 pulp screen and sieve plate
270 centrifugal chamber
280 screening chamber
290 good pulp outlet
Claims (12)
1. A pumping screen, comprising:
a pump housing;
a rotor wheel housed within the pump housing;
a drive shaft that rotatably drives the rotor wheel through the pump housing;
wherein the pump inlet of the pump shell is opposite to the front surface of the rotor impeller, the pump outlet is positioned on the peripheral side surface of the pump shell,
it is characterized in that the preparation method is characterized in that,
the pumping sieve also comprises a pulp sieve, wherein the pulp sieve divides the pump shell into a centrifugal cavity and a screening cavity, the centrifugal cavity contains the rotor impeller, and the screening cavity is provided with a good pulp outlet.
2. The pumping screen of claim 1, wherein the shaker is a screen deck secured to or integrally formed with the pump housing on the back side of the rotor wheel, the screen deck having screen openings disposed only in a radially outer region of the shaker and a central region of the shaker having no screen openings.
3. The pumping screen of claim 2, wherein the screening deck is planar.
4. A pumping screen according to claim 2, wherein the screening deck is funnel-shaped with a central indentation into the screening chamber.
5. The pumping screen of claim 2, wherein the screening deck is conically shaped with a center convex toward the centrifugal chamber.
6. The pumping screen of claim 1,
the pulp screen is a hollow structure fixed to or integrally formed with the pump casing at the back side of the rotor impeller, at least a part of the area of the peripheral side wall of the hollow structure is a screen plate,
the rotor impeller has a bend around the hollow structure at a radial outer periphery, the bend divides the rotor impeller into a centrifugal impeller portion near the drive shaft and a screening impeller portion near the distal end, a back side of the screening impeller portion of the rotor impeller being opposite to the screen plate.
7. The pumping screen of claim 6, wherein the rotor lobes are bent radially outward toward a back side of the rotor lobes.
8. The pumping screen of claim 6, wherein the rotor lobes are radially outwardly bent toward a front face of the rotor lobes.
9. A pumping screen according to claim 7 or 8, wherein the hollow structure is frustoconical, a frustoconical top surface being opposite the back side of the rotor impeller, an outer peripheral sidewall of the frustoconical forming the screening deck.
10. A pumping screen according to claim 7 or 8, wherein the hollow structure is cylindrical with a top cylindrical surface opposite the back side of the rotor wheel and an outer peripheral cylindrical wall forming the screening deck.
11. A pumping screen according to claim 7 or 8, wherein the peripheral side wall of the hollow formations is curved.
12. A screening system comprising a stock chest, a sludge chest and an accepts chest, characterized in that the screening system further comprises a pumping screen according to any of claims 1 to 11, the pump inlet of which is in direct communication with the stock chest for extracting stock, the pump outlet of which is in communication with the sludge chest and the accepts outlet of which is in communication with the accepts chest.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020271533.4U CN211713509U (en) | 2020-03-09 | 2020-03-09 | Pumping screen and pumping screening system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020271533.4U CN211713509U (en) | 2020-03-09 | 2020-03-09 | Pumping screen and pumping screening system |
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| Publication Number | Publication Date |
|---|---|
| CN211713509U true CN211713509U (en) | 2020-10-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202020271533.4U Active CN211713509U (en) | 2020-03-09 | 2020-03-09 | Pumping screen and pumping screening system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021180090A1 (en) * | 2020-03-09 | 2021-09-16 | 安德里茨（中国）有限公司 | Pumping screen and pumping screening system |
| CN113584923A (en) * | 2021-09-01 | 2021-11-02 | 安德里茨（中国）有限公司 | Pulp screening machine |
-
2020
- 2020-03-09 CN CN202020271533.4U patent/CN211713509U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021180090A1 (en) * | 2020-03-09 | 2021-09-16 | 安德里茨（中国）有限公司 | Pumping screen and pumping screening system |
| CN113584923A (en) * | 2021-09-01 | 2021-11-02 | 安德里茨（中国）有限公司 | Pulp screening machine |
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