CN111720331A

CN111720331A - Single-stage centrifugal pump with liquid collecting and draining flow channel and flow dividing partition plate having at least 2 liquid draining ports

Info

Publication number: CN111720331A
Application number: CN202010464567.XA
Authority: CN
Inventors: 何巨堂; 何艺帆
Original assignee: Luoyang Ruihua New Energy Technology Development Co ltd
Current assignee: Luoyang Ruihua New Energy Technology Development Co ltd
Priority date: 2020-05-22
Filing date: 2020-05-22
Publication date: 2020-09-29
Anticipated expiration: 2040-05-22
Also published as: CN111720331B

Abstract

A single-stage centrifugal pump provided with a liquid collecting and discharging flow channel and a flow dividing partition plate and at least 2 liquid discharging ports is used for the flow dividing and conveying of slurry so as to facilitate the recovery of flushing liquid, a main medium 1F discharged by a single-stage main impeller 1 with a rear cover plate enters a first liquid collecting and discharging sub-flow channel NPA far away from the rear cover plate of the impeller and a second liquid collecting and discharging sub-flow channel NPB close to the rear cover plate of the impeller in a liquid collecting and discharging flow channel cavity provided with the flow dividing partition plate 21, the inner edge of the flow dividing partition plate 21 points to the discharging outlet area of blades 14 of the main impeller 1, part of the main medium is introduced into the NPA and is discharged from a pump cavity through a discharging port 9A to be used as material flow 1P, and the rest of the main medium and flushing liquid discharged from a pump rear chamber; a round hole is formed in the middle of the partition plate 21 connected to the pump cavity and is vertical to the pump shaft; one side or 2 sides of the partition plate 21 can be connected with the pump cover through a guide sheet and used for guiding and supporting; the outer section of the main blade body may be provided with a main impeller diaphragm 1901.

Description

Single-stage centrifugal pump with liquid collecting and draining flow channel and flow dividing partition plate having at least 2 liquid draining ports

Technical Field

The invention relates to a single-stage centrifugal pump provided with a collection and discharge liquid flow passage dividing partition plate and at least 2 liquid discharge ports, which can be used for the divided flow conveying of slurry to facilitate the recovery of flushing liquid, wherein a main medium 1F discharged by a single-stage main impeller 1 with a back cover plate enters a first collection and discharge sub-flow passage NPA far away from the back cover plate of the impeller and a second collection and discharge sub-flow passage NPB close to the back cover plate of the impeller in a collection and discharge liquid flow passage cavity provided with the dividing partition plate 21, the inner edge of the dividing partition plate 21 points to the discharge outlet area of blades 14 of the main impeller 1, part of the main medium is introduced into the NPA and discharged from a pump cavity through a discharge port 9A to be used as the material flow 1P, and the rest of the main medium and the flushing liquid discharged from a back chamber of the pump are introduced into; a round hole is formed in the middle of the partition plate 21 connected to the pump cavity and is vertical to the pump shaft; one side or 2 sides of the partition plate 21 can be connected with the pump cover through a guide sheet and used for guiding and supporting; the outer section of the main blade body may be provided with a main impeller flow guiding partition plate 1901, and the outer end surface thereof corresponds to the inner end surface of the partition plate 21 in one plane.

Background

The main medium 1F of the present invention refers to a process fluid, i.e., the main medium 1F, which is to be transported by a centrifugal pump using a washing liquid, and may be a slurry, i.e., a solid-containing liquid; the main medium 1F before pressurization enters the main impeller cavity from the main medium inlet 1FN of the pump shell, is pressurized by the main impeller, and is discharged from the main medium outlet 9 after self pressurization.

The back pump chamber KV of the centrifugal pump according to the present invention refers to a chamber between the back cover plate 16 of the main impeller 1 and the pump casing, and is generally a chamber between the back cover plate 16 of the last stage main impeller and the pump chamber back cover 312.

The main impeller of the pump of the present invention uses a back cover plate.

The back pump cavity flushing fluid CXY of the centrifugal pump refers to flushing fluid for flushing the back pump cavity KV.

The back blade BYP of the main impeller of the present invention refers to a blade which is arranged in the back pump cavity KV and can rotate along with the pump shaft, and may be the back blade 19 of the main impeller 1, i.e. a blade arranged on the back of the back cover plate.

The main body flow direction of the flushing liquid CXY passing through the rear pump cavity KV is that the flushing liquid CXY firstly enters the inner side area of the rear pump cavity KV close to the pump shaft, then reaches the outer side area of the rear pump cavity KV far away from the pump shaft, then leaves the rear pump cavity KV, and continuously flows and is discharged out of the pump body.

The back pump cavity flushing fluid CXY disclosed by the invention generally flows in a main body direction of passing through the back pump cavity KV, firstly enters an inner side area of the back pump cavity KV, which is close to a pump shaft (or a shaft sleeve), then flows through a middle area of the back pump cavity to reach an outer side area of the back pump cavity KV, which is far away from the pump shaft, then leaves the back pump cavity KV, and continuously flows and is discharged out of a pump body.

Generally, when the back blade BYP is arranged in the centrifugal pump, the main flow direction of the flushing liquid CXY passing through the back pump cavity KV is that the flushing liquid CXY firstly enters an inner side inlet area of the back blade BYP, then flows through the back blade cavity, is thrown out of the back blade cavity after energy is applied by the back blade BYP, then leaves the back pump cavity KV, and continuously flows and is discharged out of a pump body.

Conventional centrifugal pump does not establish dedicated back pump chamber flush fluid discharge port BPN, and back pump chamber flush fluid discharges the pump chamber in the lump with whole main medium after the pump chamber internal mixing, and at this moment, the discharge path system of back pump chamber flush fluid: leave behind the pressure boost of pump chamber flush fluid entering pressure boost back main medium's runner intracavity, flow in the lump after mixing with whole main medium behind the pressure boost, finally, in the lump through pressure boost back main medium row mouth 9 discharge pump cavity, because pressure boost back flush fluid and pressure boost back main medium mix completely together, its advantage is that simple, the compactness of material structure is arranged to the pump case, but has following shortcoming:

firstly, the components of the flushing liquid cannot be recovered at low cost, because the flushing liquid with a small quantity is diluted by all the pressurized main media and the pressurized main media are completely mixed together, the dilution degree of the main fluid of the flushing oil discharged by the pump reaches the maximum, the flushing oil is not beneficial to recycling, and the cost of the flushing oil recycling is increased; when the value of the flushing liquid is higher than that of the main medium, the value of the flushing liquid is reduced, and the loss is large;

secondly, the main medium is polluted by the washing liquid after pressurization, and the scale of a subsequent treatment system is increased.

The present invention relates to the transportation of a slurry having a high concentration of solid particles and a high concentration of asphaltenes, and will be described below by way of example.

Based on the existing scheme for discharging flushing liquid in the rear pump cavity of the centrifugal pump, the oil residue conveying pump at the bottom of the vacuum fractionating tower for generating oil in the reaction processes of direct coal hydrogenation liquefaction, residual oil suspension bed hydrocracking, residue oil boiling bed hydrocracking and the like typically adopts a structure that the flushing liquid (flushing oil) and an auxiliary impeller are used for protecting a sealing part of a mechanical sealing system MFU of a pump shaft, the pump PAST-KPUMP, between the pump shaft mechanical sealing system MFU and main pump impeller, the flushing mechanism or sealing mechanism is characterized by that an auxiliary impeller, fixed guide vanes and main impeller back blades are set, the flushing oil (or sealing oil) can be passed through the auxiliary impeller and pressurized, then flows through the fixed guide vane to prevent the rotational flow from entering an inlet area of a back blade of the main impeller, and then is pressurized by the back blade of the main impeller, and then leaves a back cavity of the main pump to enter a discharge flow channel (such as a volute) of the main pump to be mixed with a main medium discharged by the main impeller and then is recovered or treated together. According to other material conditions and operation requirements of a factory, the oil residue delivery pump PAST-KPUMP can be provided without one or more of an auxiliary impeller, a fixed guide vane and a main impeller back vane.

Taking a bottom oil residue delivery pump PAST-KPUMP of a KT tower of a vacuum fractionating tower of a coal hydrogenation direct liquefaction reaction process for generating oil with the yield of distilled oil of a coal hydrogenation direct liquefaction product of 100 ten thousand tons/year as an example, the loss amount is large according to a conventional oil rear pump cavity flushing fluid discharge mode; the flushing oil is wax oil distillation oil separated from oil generated by direct coal hydrogenation liquefaction through a vacuum fractionating tower KT or hydrogen-supplying solvent wax oil and/or heavy diesel oil separated from oil generated in a hydrogen-supplying solvent oil hydrogenation reaction process, and because the recovery of the flushing oil from the direct coal hydrogenation liquefaction residue is extremely difficult or too high in cost, the flushing oil mixed into the direct coal hydrogenation liquefaction residue is usually used as a substitute of coal for combustion of a circulating fluidized bed boiler or gas making of a gasification furnace, and the price is only 500-700 yuan/ton. Thus, the value of the flushing oil is 4000-5000 yuan/ton (calculated as 4500 yuan/ton below) higher than that of the liquefied residue, calculated according to 7600 hours/year of the device operation, 400-600 kg/hour of the flushing oil consumed by each pump is 3040-4560 tons/year, and the loss amount is as high as 1368-2052 yuan/year because the flushing oil cannot be recovered. Although 100-200% of KT tower bottom oil of discharged liquefaction residues is generally recycled and returned to the bottom of the vacuum tower for tangential feeding to form rotational flow in order to prevent coking at the bottom of the vacuum tower, a small amount of flushing oil can be separated, or 50-100% of KT tower bottom oil of discharged liquefaction residues is returned to recycled gasification flushing oil in a feeding flash evaporation section of the vacuum tower (actually, the recycle ratio of the operation cannot be too high to prevent repeated heating and coking of asphaltenes) can be separated by 33-50% of flushing oil at most, and the economic loss caused by the loss of the final flushing oil is still huge and can reach 684-1354 ten thousand yuan/year. The above analysis is only statistical data of the operation mode using 1 working pump (while 1 pump is standby), and if the operation mode using 2 working pumps (while 1 pump is standby) is used to ensure the operation reliability, the loss is increased by almost 1 time, and the loss amount is more huge.

In order to overcome the defects or reduce the degree of the defects, the structure of the centrifugal pump using the flushing liquid in the rear pump cavity is improved, and the purpose is to realize the separation of the discharging of the flushing liquid and the discharging of the main medium; since the flushing oil enters the discharge space of the main impeller to be mixed with the main medium after leaving the outer edge of the main impeller, complete separation of the flushing oil and the main medium can hardly be achieved, and therefore a relative separation mode is selected to control part of the main medium to be not mixed with the flushing liquid and to be discharged in a branch manner, and therefore, an adaptive design needs to be performed on a discharge path of the flushing liquid discharged from a pump cavity behind the centrifugal pump, which inevitably involves a change in the discharge path of the main medium leaving the pump shell after being partially pressurized.

The basic idea of the invention is: a single-stage centrifugal pump provided with a liquid collecting and discharging flow channel and a flow dividing partition plate and at least 2 liquid discharging ports is used for the flow dividing and conveying of slurry so as to facilitate the recovery of flushing liquid, a main medium 1F discharged by a single-stage main impeller 1 with a rear cover plate enters a first liquid collecting and discharging sub-flow channel NPA far away from the rear cover plate of the impeller and a second liquid collecting and discharging sub-flow channel NPB close to the rear cover plate of the impeller in a liquid collecting and discharging flow channel cavity provided with the flow dividing partition plate 21, the inner edge of the flow dividing partition plate 21 points to the discharging outlet area of blades 14 of the main impeller 1, part of the main medium is introduced into the NPA and is discharged from a pump cavity through a discharging port 9A to be used as material flow 1P, and the rest of the main medium and flushing liquid discharged from a pump rear chamber; a round hole is formed in the middle of the partition plate 21 connected to the pump cavity and is vertical to the pump shaft; one side or 2 sides of the partition plate 21 can be connected with the pump cover through a guide sheet and used for guiding and supporting; the outer section of the main blade body may be provided with a main impeller flow guiding partition plate 1901, and the outer end surface thereof corresponds to the inner end surface of the partition plate 21 in one plane.

Compared with the discharge scheme of the conventional centrifugal pump after all flushing liquid and main medium are mixed, the invention has the advantages that the relative separation discharge of the flushing liquid and the main medium can be realized, at least one part of 2P has different purposes than at least one part of 1P, the low-cost recycling of the flushing liquid in the 2P is facilitated, and the purity of the 1P can be improved; the transfer pump KP and 2P of the KT tower bottom oil residue of the vacuum fractionating tower can directly enter the feeding or discharging section of a KT feeding heating furnace tube or a KT flash evaporation section to separate flushing liquid and residual oil and can also return to the hydrogenation reaction process for cyclic reaction, and the benefit is obviously increased by reducing the loss of the flushing liquid.

The invention is characterized in that the concept of 'collecting and discharging liquid flow channel is provided with a flow dividing partition plate to recover flushing liquid' is definitely provided, which is equivalent to the improvement of the conventional discharging guide vane (radial guide vane) of the centrifugal pump, and the application occasion of the invention is wider because the discharging guide vane of the centrifugal pump is a basic component. The invention is suitable for the delivery pumps of various media, and therefore has a certain universal application value in the related fields. The pump has a mixing function, while the present invention imparts a separating function to the pump.

The invention does not increase the volume of the pump cavity basically, thus having simple structure and easy design, manufacture, installation and maintenance.

The invention is used for a single-stage impeller centrifugal pump, and the inducer can be arranged in front of the first-stage impeller.

The centrifugal pump of the invention preferably adopts a pump shaft cantilever support mode to simplify the pump structure.

According to the centrifugal pump disclosed by the invention, the vertical installation mode of the pump shaft is preferably selected, so that the adverse effect caused by gravity is weakened, the eccentricity of the pump shaft in the operation process is reduced, and the stability of the flow field of the pump back chamber is facilitated.

Patent zl200610118809.x high temperature high impurity ratio centrifugal coal slurry pump, which is a cantilever type structure single-stage single-suction vertical pump, describes a high temperature high impurity ratio centrifugal coal slurry pump. The pump seat, the pump frame and the rear heating cavity form an outer shell, and the front cover plate, the rear cover plate and the water outlet section form an inner shell to form a double-shell structure. The impeller structure is a double-resistance impeller structure. The packing seal structure is a detachable integral packing seal structure. And the device also comprises a group of heating mechanisms which can heat and insulate each part of the pump. The high-temperature high-impurity-ratio centrifugal coal slurry pump integrates the functional characteristics of a slag slurry pump, a chemical pump and a high-rotating-speed pump, solves the problems of abrasion of flow passage parts such as an impeller and a pump body, siltation and blockage of solids in a certain area, sealing, heating and heat preservation and the like, and has practical value.

According to the specification of patent zl200610118809.x, the pump with the structure uses an open impeller (a main impeller rear cover plate is arranged, a main impeller front cover plate is not arranged), a back blade is arranged on the back of the main impeller rear cover plate, used flushing oil flows through the back space of the main impeller rear cover plate, the flushing oil is pushed by the back blade of the main impeller rear cover plate to increase pressure and then is thrown out of a main impeller back chamber, and after being mixed with a main medium thrown out by the main impeller, the flushing oil flows through a liquid collecting and discharging cavity together, and leaves a pump body after passing through a material discharging pipe section and is sent into an external conveying pipeline; the patent zl200610118809.x does not relate to the technical concept of the single-stage centrifugal pump with at least 2 liquid discharge ports on the flow dividing partition plate of the liquid collecting and discharging channel of the invention, and does not have the function of the invention.

The technical scheme similar to the invention is not reported.

The first purpose of the invention is to provide a single-stage centrifugal pump provided with a liquid collecting and discharging flow passage and flow dividing partition plate with at least 2 liquid discharging ports.

The second purpose of the invention is to provide a single-stage centrifugal pump with at least 2 liquid discharge ports on the liquid collecting and discharging flow channel and flow dividing partition plate, and simultaneously, a main impeller back blade, a fixed guide vane and an auxiliary impeller are used, flushing oil sequentially passes through the auxiliary impeller, the fixed guide vane and the flow dividing impeller back blade, a mechanical sealing part of a pump shaft is arranged on one side of the auxiliary impeller, which is far away from a main pump cavity, and the outside of the mechanical sealing, which is far away from one side of the auxiliary impeller, is an environmental space.

The invention also provides a single-stage centrifugal pump provided with a liquid collecting and discharging flow channel and a flow dividing partition plate with at least 2 liquid discharging ports, which belongs to a centrifugal pump without a shaft seal.

The fourth purpose of the invention is to provide a single-stage centrifugal pump provided with a liquid collecting and discharging flow passage and flow dividing partition plate with at least 2 liquid discharging ports, wherein the main medium belongs to the bottom oil residue of a KT tower of a vacuum fractionating tower for generating oil in the hydrogenation reaction process of heavy hydrocarbon.

Disclosure of Invention

The invention provides a single-stage centrifugal pump provided with a liquid collecting and discharging flow channel and a flow dividing partition plate and at least 2 liquid discharging ports, which is characterized in that:

the single-stage impeller centrifugal pump KPUMP conveys a main medium liquid material 1F possibly containing solid particles, a pump shaft is sealed by using a flushing liquid, the flushing liquid flows through a rear pump cavity KV behind a rear cover plate 16 of a main impeller 1 of the pump, is mixed with the main liquid material thrown out by the main impeller 1, flows into a collecting and discharging liquid channel V100 corresponding to the main impeller 1 and then is discharged out of the pump cavity;

the back pump cavity KV refers to a cavity between the back cover plate 16 of the main impeller 1 and the pump shell;

the liquid collecting and discharging flow passage V100 is characterized in that at least 1 flow dividing partition plate LD-GBX is arranged in the liquid collecting and discharging flow passage V100, the inner side of the flow dividing partition plate LD-GBX points to the discharging outlet area of the main blade 14 of the main impeller 1, at least 2 sub-flow passages are formed, and at least 2 corresponding liquid discharging ports are formed;

the liquid collecting and discharging flow channel V100 comprises a liquid collecting and discharging sub-flow channel NP9 closest to a rear cover plate of the impeller, a liquid collecting and discharging sub-flow channel NP1 closest to a front cover plate of the impeller, and possibly sub-flow channels positioned between the flow channel NP9 and the flow channel NP1, wherein each sub-flow channel corresponds to 1 liquid discharging port;

when the impeller works, the circumference of the inner side edge of the flow dividing partition plate LD-GBX is not contacted with the maximum outer edge of the final-stage impeller KYL;

between the liquid collecting and discharging sub-flow passages NP9, no material passing through the flow dividing partition plate LD-GBX is connected in series.

In the invention, generally, the flow dividing partition plate LD-GBX arranged in the collecting and discharging liquid flow channel V100 is connected or assembled with the pump cover in a seamless way except for the material inlet, and the flow dividing partition plate LD-GBX is a solid leakage-free partition plate.

In the invention, generally, the inner side edge of the flow dividing partition plate LD-GBX is in a ring shape, the plane of the ring is vertical to and concentric with the pump shaft, and the inner side edge of the flow dividing partition plate LD-GBX is in a parabola shape after being divided along the central line of the pump shaft; when the impeller is in a working state, the circumference of the inner side edge of the flow dividing partition plate LD-GBX is not in contact with the maximum outer edge of the last-stage impeller KYL, and the gap between the circumference of the inner side edge of the flow dividing partition plate LD-GBX and the maximum outer edge of the last-stage impeller KYL is 0.5-3 mm.

In the invention, one side or 2 sides of the flow dividing clapboard LD-GBX can be connected with a pump cover or other flow dividing clapboards through the guide vanes and used as the support or the liquid drainage guide of the flow dividing clapboard LD-GBX; on any side of the flow dividing partition plate LD-GBX, the number of the arranged guide vanes LD-GBX-YP is usually 2-6, and the shape of the guide vanes LD-GBX-YP is usually streamline backward bending vanes.

In the present invention, the flow divider LD-GBX is generally sandwiched between the front and rear pump covers and may be secured by pins or screws.

In the invention, a main impeller flow dividing partition plate YL-GBX can be arranged at the outer side section of the main blade 14 body of the main impeller 1 to divide the flow channel of the main impeller 1 into 2 or more sub-flow channels;

generally, main impeller flow dividing partitions YL-GBX correspond to flow dividing partitions LD-GBX arranged in the collecting and discharging liquid channel V100 one by one, and the mutually corresponding main impeller flow dividing partitions YL-GBX and the flow dividing partitions LD-GB of the collecting and discharging liquid channel V100 are in the same plane;

generally, the main impeller flow-dividing partition plate YL-GBX is in a circular ring shape, and the plane of the main impeller flow-dividing partition plate YL-GBX is perpendicular to and concentric with the pump shaft;

generally, the outer edge radius of the main impeller flow dividing partition plate YL-GBX is the same as the maximum radius of the main impeller 1, and the inner edge radius of the main impeller flow dividing partition plate YL-GBX is 0.50-0.90 of the maximum radius of the main impeller 1;

in general, the main impeller flow dividing partitions YL to GBX correspond to the flow dividing partitions LD to GBX provided in the drainage flow path V100 in one-to-one correspondence, and the number of the main impeller flow dividing partitions YL to GBX is the same.

In the invention, series flow gaps can be arranged on the flow dividing partition plate LD-GBX arranged in the collecting and discharging liquid flow channel V100 under special conditions, and a small amount of liquid mixing of adjacent sub flow channels is allowed; the ratio of the flow area of the series flow holes to the cross-sectional area of the related small runner sub-runners is lower than 0.02.

In the invention, the main impeller can be an open impeller, and a rear cover plate is used without a front cover plate.

In the invention, generally, the inner side edge of a flow dividing partition plate LD-GBX arranged in a collecting and discharging liquid channel V100 is integrally in a ring-shaped CYC1, and the plane of the ring is vertical to and concentric with a pump shaft;

the diameter of the back cover plate 16 of the main impeller 1 is larger than that of the circular CYC1, and the back cover plate radially extends into a sub liquid discharge area NP9 formed by the liquid collecting and discharging partition plate 21 and closest to the back cover of the pump, so that all flushing liquid is directly discharged into the sub liquid discharge area NP 9;

the outer portion of the main blade 1 body, in spatial relationship with the secondary drainage region NP9, may be selected from 1 of the following:

firstly, all the liquid does not enter a sub liquid discharge region NP9 space;

the part close to the rear cover plate of the main impeller enters the space of the sub liquid discharge region NP 9.

In the present invention, generally, the back vanes 19 of the back shroud 16 of the main impeller 1 are mounted in the pockets WC10 of the pump back cover 312, limiting the main impeller back chamber volume to facilitate flushing oil filling this area.

In the present invention, generally, in the centrifugal pump KPUMP, the collection/discharge flow channel V100 includes 2 sub-flow channels: the ratio of the cross-sectional area S9 of the sub-flow channel NP9 to the cross-sectional area S1 of the sub-flow channel NP1 of the liquid collecting and discharging sub-flow channel NP9 close to the back cover plate of the impeller to the cross-sectional area NP1 close to the front cover plate of the impeller is K100, (S9)/(S1), the value of K100 may be selected from 1 of the following:

①K100＝0.50～1.00；

②K100＝0.30～0.50；

③K100＝0.20～0.30；

④K100＝0.05～0.20；

⑤K100＜0.05。

in the invention, generally, a flow dividing partition plate LD-GBX is arranged in the liquid collecting and discharging channel V100, an outlet pipe section of the sub-liquid discharging cavity is converted into a circular pipeline in a mode of gradually changing the internal section form, and the circular interface is butted with a pipeline system.

In the present invention, generally, in the centrifugal pump KPUMP, the collection/discharge flow channel V100 includes 2 sub-flow channels: the ratio of the discharge flow rate W9 of the sub-flow channel NP9 to the discharge flow rate W1 of the sub-flow channel NP1 is K300, K300 is (W9)/(W1), and the value of K300 may be selected from 1 of the following:

①K300＝0.50～1.00；

②K300＝0.30～0.50；

③K300＝0.20～0.30；

④K300＝0.05～0.20；

⑤K300＜0.05。

in the invention, in general, in a centrifugal pump KPUMP, a back blade 19 is arranged on the plate surface of one side of a rear pump cover 16 of a main impeller 1 facing a rear pump cover; typically, the back vane 19 is a radial straight vane.

In the present invention, the flow path of the external flushing fluid CXY of the centrifugal pump KPUMP before being input to the back pump chamber KV may be selected from one of the following:

firstly, after entering a rear pump cavity KV flushing fluid input flow channel, entering the rear pump cavity KV;

pressurizing the gas by flowing through the auxiliary impeller chamber, then flowing through the optical back of the auxiliary impeller cover plate on one side of the auxiliary impeller, and entering a back pump cavity KV;

thirdly, the gas flows through the auxiliary impeller cavity for pressurization, then flows through an anti-rotation flow channel formed by the light back surface of an auxiliary impeller cover plate on one side of the auxiliary impeller, which faces the main impeller, and the fixed guide vane, and then enters a back pump cavity KV;

fourthly, the oil flows through the axial clearance at the outer side of the pump shaft or the pump shaft sleeve and enters the rear pump cavity KV;

the centrifugal pump KPUMP belongs to the centrifugal pump of the motor without shaft seal, the external supply flushing liquid enters the motor chamber through the flushing liquid inlet of the motor chamber, then leaves the motor chamber after flowing through the motor chamber, then flows through the anti-backflow channel from the motor chamber to the back pump chamber KV, and enters the back pump chamber KV;

and the centrifugal pump KPUMP belongs to a non-shaft seal motor centrifugal pump, washing liquid is externally supplied, enters a motor chamber through a washing liquid inlet of the motor chamber, flows through the motor chamber, is boosted through an auxiliary impeller arranged in the motor chamber, leaves the motor chamber, flows through the motor chamber to a backflow prevention channel of a back pump cavity KV, and enters the back pump cavity KV.

In the invention, the prime mover at the driving end of the centrifugal pump KPUMP can be selected from 1 of the following:

firstly, a motor; a second frequency conversion motor; thirdly, a hydraulic motor; fourthly, the oil engine; gas engine; a pneumatic motor; and (c) a steam turbine.

In the present invention, typically, centrifugal pump KPUMP uses an external drive, with a mechanical pump shaft sealing system.

In the present invention, generally, in a centrifugal pump KPUMP, at least a portion of the pump shaft is exposed to the environment, a pump shaft sealing system U80 of the centrifugal pump shaft is provided that prevents leakage of the primary media to the environment.

In the present invention, typically, centrifugal pump KPUMP, flushing fluid CXY flows through the secondary impeller and into pump chamber housing Q10;

the pump shaft sealing system U80 is located on the outer side of the auxiliary impeller to form a spatial relationship that the auxiliary impeller, the pump shaft sealing system U80 and the external driver are close to each other in sequence, the inner side of the pump shaft sealing system U80 is adjacent to the auxiliary impeller chamber, and the outer side of the pump shaft sealing system U80 is adjacent to the environment.

The centrifugal pump KPUMP can be a shaft seal-free centrifugal pump, and is selected from one of a shielding electric centrifugal pump, a submerged electric centrifugal pump and a magnetic centrifugal pump.

In the invention, the centrifugal pump KPUMP can be a shaftless electric centrifugal pump, and an auxiliary liquid FZL input system is arranged;

the auxiliary liquid FZL is used as flushing liquid and is used for preventing a main medium in a pump cavity shell Q10 from being connected into a cavity of a motor without a shaft seal in series, the operating pressure of an auxiliary liquid input system is greater than the operating pressure of the main medium in a pump cavity shell Q10, so that at least a part of the auxiliary liquid FZL enters a rear pump cavity KV in the pump cavity shell Q10 through a flow passage and is discharged out of the pump cavity shell Q10 after flowing through the rear pump cavity KV;

auxiliary liquid FZL which is flushing liquid CXY for the rear pump cavity KV;

the used motor without shaft seal is provided with an injection interface E-K1 of lubricating liquid and/or cooling liquid EL of a cavity of the motor without shaft seal; the lubricating liquid and/or the cooling liquid EL refer to a liquid for cooling and lubricating the rotor and the cavity of the motor without the shaft seal;

the discharge of the lubricating and/or cooling fluid EL from the motor cavity without shaft seal serves to prevent the auxiliary fluid FZL and/or the main medium in the pump cavity from flowing into the motor cavity without shaft seal.

the auxiliary liquid FZL is used as flushing liquid and is used for preventing a main medium in the pump cavity shell Q10 from being connected into a cavity of the motor in series, the operating pressure of an auxiliary liquid input system is greater than the operating pressure of the main medium in the pump cavity shell Q10, so that at least a part of the auxiliary liquid FZL enters a rear pump cavity KV in the pump cavity shell Q10 through a flow channel and is discharged out of the pump cavity shell Q10 after flowing through the rear pump cavity KV;

the lubricating liquid and/or the cooling liquid EL of the shaft seal-free motor cavity are discharged to prevent the auxiliary liquid FZL and the main medium in the pump cavity from flowing into the shaft seal-free motor cavity;

when the shaftless motor works normally, the operating pressure of a liquid existing area in the cavity of the shaftless motor is greater than the operating pressure of a main medium in the pump cavity shell Q10 and is also greater than the operating pressure of fluid in the auxiliary liquid FZL of the canned motor pump, so that at least a part of lubricating liquid EL enters the auxiliary liquid system through the flow channel and is mixed with the auxiliary liquid FZL to form mixed liquid EL-FZL, at least a part of the mixed liquid EL-FZL enters the rear pump cavity KV in the pump cavity shell Q10 through the flow channel and flows through the rear pump cavity KV and then is discharged out of the pump cavity shell Q10;

and the mixed solution EL-FZL is the flushing fluid CXY for the rear pump cavity KV.

The arrangement mode of the centrifugal pump KPUMP can be selected from 1 of the following modes:

firstly, horizontally arranging a pump shaft;

secondly, the pump shaft is vertically arranged, and the motor is positioned above the pump cavity;

and thirdly, the pump shaft is vertically arranged, and the motor is positioned below the pump cavity.

The invention, centrifugal pump KPUMP, arrange the lining of cavity wall inside pump chamber shell Q10, its use can be selected from 1 or several in the following:

firstly, an erosion-resistant bushing;

② wear-resisting lining

Thirdly, corrosion-resistant lining;

fourthly, the thermal shock resistant bushing;

low temperature resistant lining.

The invention, centrifugal pump KPUMP, the use of arranging a liner for the inner wall of a liquid inlet pipe and/or a liner for the inner wall of a liquid outlet pipe in a pump chamber housing Q10, can be selected from 1 or several of the following:

firstly, an erosion-resistant bushing;

② wear-resisting lining

Thirdly, corrosion-resistant lining;

fourthly, the thermal shock resistant bushing;

low temperature resistant lining.

In the centrifugal pump KPUMP, an inducer can be arranged at the inlet of the main impeller.

In the present invention, generally, in the centrifugal pump KPUMP, the pump shaft is arranged in a single-sided cantilevered arrangement.

The main medium delivered by the centrifugal pump KPUMP can have 1 or more of the following media:

contains solid components;

② contains corrosive components;

③ containing a combustion component;

fourthly, toxic components are contained;

containing radioactive components;

sixthly, the volatile component is contained;

contains easily coagulated components;

eighthly, containing bubble liquid;

ninthly, high-temperature liquid;

low temperature liquid charge in the red cavity;

high-pressure liquid material.

The operating conditions of the centrifugal pump KPUMP can be selected from 1 or more of the following:

the main medium 1F conveyed by a centrifugal pump KPUMP is bottom oil residue of a KT tower of a vacuum fractionating tower for directly liquefying coal to generate oil by hydrogenation, and the operation conditions are as follows: the temperature is 280-380 ℃, and the solid concentration is 35-60 wt%;

secondly, the main medium 1F conveyed by the centrifugal pump KPUMP is bottom oil residue of a KT tower of a vacuum fractionating tower for generating oil by hydrocracking a residual oil suspension bed, and the operating conditions are as follows: the temperature is 300-380 ℃, and the solid concentration is 0.05-10 wt%;

thirdly, the main medium 1F conveyed by the centrifugal pump KPUMP is the bottom oil residue of a KT tower of a vacuum fractionating tower for generating oil by residue oil boiling bed hydrocracking, and the operating conditions are as follows: the temperature is 300-380 ℃, and the content of asphaltene is 20-80 wt%;

④ the operation conditions of the main medium 1F conveyed by the centrifugal pump KPUMP are that the temperature is-150-650 ℃, the pressure is 0.1-40.0 MPa, and the volume flow rate of the main medium 1F is 0.1-10000 m³The solid concentration is 0.01-50 wt%;

⑤ the operation conditions of the main medium 1F conveyed by the centrifugal pump KPUMP are that the temperature is-150-650 ℃, the pressure is 0.1-40.0 MPa, and the volume flow rate of the main medium 1F is 0.1-10000 m³The solid concentration is 0.01-50 wt%, and the pump main impeller applies energy to the main medium 1F to increase the pressure by 0.10-5.0 MPa.

In the invention, the main medium 1F conveyed by the centrifugal pump KPUMP can be oil residue at the bottom of a KT tower of a reduced pressure fractionating tower for directly liquefying R10 in the reaction process of hydrogenation of heavy hydrocarbon; the direction of the material discharged from the liquid collecting and discharging sub-flow passage NP9 closest to the rear cover plate of the impeller in the liquid collecting and discharging flow passage V100 of the conveying pump KPUMP can be selected from 1 of the following types:

feeding the material into a furnace tube of a feeding heating furnace of a KT (vacuum distillation column);

feeding the material into a discharge material of a KT feeding heating furnace tube of a vacuum fractionating tower;

thirdly, entering a flash evaporation section of a KT (vacuum fractionating tower);

and fourthly, removing the heavy hydrocarbon material and performing a hydrogenation reaction in the R10 cycle reaction process.

Drawings

The drawings are intended to depict only the invention, but not to limit the invention to the precise form, function, and application of the invention.

In order to describe the difference between the present invention and the similar conventional solutions, the functional solution of the conventional centrifugal pump structure provided with the discharging guide wheels or guide vanes is described based on fig. 1 to 4.

Fig. 1 is a front view of a conventional volute energizer of a single-stage centrifugal pump equipped with drain vanes.

FIG. 2 is an axial center, vertically sectioned left side view of the centrifugal pump of FIG. 1.

FIG. 3 is an elevation view of the collection and drainage guide vanes of the centrifugal pump of FIG. 1.

Fig. 4 is a front view of the main impeller of the centrifugal pump of fig. 1.

In fig. 1, 1 is a main impeller, 8 is a main impeller liquid inlet, 9 is a pump body liquid outlet, 15 is a main impeller shaft cap (or called as a main impeller top cap), 27 is a drainage collecting and guiding area, 29 is a drainage collecting and diverting area, 31 is a volute, and 32 is a drainage pipe section.

In fig. 2, 16 is a main impeller rear cover, 17 is a main impeller front cover, 18 is a main impeller flow channel region, 19 is a back blade of a main impeller rear cover plate, 27 is a collected and discharged liquid guiding region, 29 is a collected and discharged liquid diverting region, 311 is a pump case front cover plate, 312 is a pump case rear cover plate, 701 is a pump shaft, and 702 is a pump shaft sleeve.

In fig. 3, 25 is a drainage guide vane (guide vane), 27 is a drainage guide area, and an inner edge distribution virtual ring C100 and an outer edge distribution virtual ring C200 of the guide vane in the drainage guide area are shown.

In fig. 4, 11 is a main impeller back cover plate, 12 is a main impeller back cover plate outer edge, 13 is a main impeller inlet area outer boundary line, 14 is a main impeller blade, and 15 is a main impeller shaft cap (or called a main impeller top cap). The blades 14 of the main impeller 1 are backward curved blades.

As shown in fig. 1 to 4, a liquid material (main medium) 1F to be pressurized enters a blade area of the main impeller through a liquid inlet 8 of the main impeller 1, and obtains a rotation speed and a centrifugal external throwing speed under the pushing of blades 14 of the main impeller 1.

As shown in fig. 1 to 4, even if the blades 14 are backward bent blades, the fluid thrown by the main impeller still has large kinetic energy, and in order to convert the kinetic energy into static pressure energy effectively, it is necessary to use a device for gradually reducing the flow rate of the fluid, and the pump casing on the outer ring of the main impeller is generally made into a snail shape, and the function of the snail shape is not only to collect the fluid thrown by the impeller and send the collected fluid to the discharge pipe 32, but also to gradually reduce the speed of the fluid thrown by the impeller in the pump casing, so that part of the kinetic energy is converted into static pressure energy effectively. In order to improve the conversion efficiency of kinetic energy into static pressure energy, guide vanes, such as a fixed disk with guide vanes, i.e., a liquid collecting and discharging guide wheel, may be assembled at the outer edge of the main impeller in the pump casing, and in the single-stage impeller pump shown in fig. 1, the liquid collecting and discharging guide vanes (guide vanes) are fixed on the pump back cover plate 312, and no guide wheel disc is additionally provided.

The following pump structure and flushing oil flow path features can be seen from fig. 1 to 4:

the plane of the panel of the liquid collecting and discharging blade 25 arranged on the conventional liquid discharging guide blade does not intersect with the plane of the main impeller blade 14 and is generally in parallel relation;

1 main impeller corresponds to 1 liquid collecting and draining guide area 27, 1 liquid collecting and draining diversion area 29, 1 discharging pipe section 32 and 1 liquid discharging port 9;

flushing liquid discharged from the back blades 19 of the back cover plate of the main impeller is mixed with all main media discharged from the blades 14 of the main impeller.

FIG. 5 is a front view showing the structure 1 of the "single-stage centrifugal pump with at least 2 discharge ports provided with a dividing wall of the liquid collecting/discharging channel" according to the present invention.

FIG. 6 is an axially centered, vertically split left side view of the centrifugal pump of FIG. 5.

Fig. 7 is a front view of a sump separator plate of the centrifugal pump shown in fig. 5.

In fig. 5, 1 is a main impeller, 8 is a main impeller liquid inlet, 9 is a pump body liquid outlet (2 liquid outlets in total for 9A and 9B), 15 is a main impeller shaft cap (or called as a main impeller top cap), 21 is a liquid collecting and discharging cavity partition plate, 22 is a virtual ring distributed on the outer edge of a liquid collecting and discharging cavity partition plate guide vane, 25 is a liquid collecting and discharging cavity partition plate guide vane, 27 is a liquid collecting and discharging guide area (2 in total for 27A and 27B), and 29 is a liquid collecting and discharging diversion area (2 in total for 29A and 29B).

In fig. 6, 16 is the rear cover of the main impeller, 17 is the front cover of the main impeller, 18 is the flow channel area of the main impeller, 19 is the back blade of the rear cover plate of the main impeller, 21 is the partition plate of the liquid collecting and discharging cavity, 27A is the front liquid collecting and discharging flow guiding area, 27B is the rear liquid collecting and discharging flow guiding area, 29A is the front liquid collecting and discharging flow guiding area, 29B is the rear liquid collecting and discharging flow guiding area, 311 is the front cover plate of the pump casing, 312 is the rear cover plate of the pump casing, 701 is the pump shaft, and 702 is the pump shaft sleeve.

The front side drainage guide area refers to a sub-drainage flow channel cavity close to the front cover 17 of the main impeller.

The rear side drainage guide area refers to the sub-drainage flow channel cavity close to the rear cover 16 of the main impeller.

In fig. 7, 21 is a partition plate of the liquid collecting and discharging cavity, 22 is a virtual ring of the outer edge of the partition plate guide vane of the liquid collecting and discharging cavity, 23 is the inner edge of the partition plate of the liquid collecting and discharging cavity, 24 is the outer edge of the partition plate of the liquid collecting and discharging cavity, 25A is the partition plate guide vane (guide vane) of the front liquid collecting and discharging cavity, 27A is the guide area of the front liquid collecting and discharging cavity of the

partition plate

21, and 29A is the diversion area of the front liquid collecting and discharging cavity of the partition plate 21.

As shown in fig. 5 to 7, the liquid material (main medium) 1F to be pressurized enters the blade area of the main impeller through the liquid inlet 8 of the main impeller 1, and obtains a rotation speed and a centrifugal external throwing speed under the pushing of the blades 14 of the main impeller 1. The blades of the main impeller 1 are backward bent blades.

As shown in fig. 5 to 7, the liquid collecting and discharging cavity partition plate 21 divides the liquid collecting and discharging area into 2 sub-liquid collecting and discharging areas, that is, a front sub-liquid collecting and discharging area DA and a rear sub-liquid collecting and discharging area DB, the liquid thrown out by the main impeller blades 14 is divided into 2 paths, the first path of main medium enters the sub-liquid discharging area DA, the second path of main medium and the washing liquid thrown out by the main impeller rear cover plate back blades 19 are mixed and then enter the sub-liquid discharging area DB, and due to the inertia effect of the liquid flowing at high speed, most of the washing liquid thrown out by the main impeller rear cover plate back blades 19 even all enter the sub-liquid discharging area DB.

As shown in fig. 5 to 7, the drainage collecting cavity partition plate is provided with drainage collecting cavity guide vanes (guide vanes) for guiding and supporting, and the drainage collecting cavity may not use drainage collecting cavity guide vanes (guide vanes) according to actual needs, which is suitable for the transportation of the main medium 1F with high solid content.

In the case of transporting the main medium 1F having a high solid content, the main impeller 1 is usually an open blade, and a front cover plate of the main impeller is not provided, so that accumulation of foreign matters is prevented.

As shown in fig. 5 to 7, the liquid collecting/discharging chamber partition plate 21 divides the sub-set liquid discharging areas DA and DB, and the liquids in the 2 chambers are not communicated or connected to each other.

The following features can be seen from fig. 5 to 7:

the plane of the panel of the liquid collecting and discharging cavity partition plate 21 is intersected with the space of the main impeller blade 14;

1 main impeller corresponds to 2 liquid collecting and draining guide flow areas (27A, 27B), 2 liquid collecting and draining diversion areas (29A, 29B), 2 discharging pipe sections (32A, 32B) and 2 liquid discharging ports (9A, 9B);

thirdly, the washing liquid discharged by the back blade 19 of the back cover plate of the main impeller is mixed with part of the main medium discharged by the blades 14 of the main impeller, and is discharged out of the pump body through the sub-fluid discharge area DB; the remaining part of the main medium discharged from the main impeller blades 14 is discharged from the pump body through the sub-fluid discharge area DA without being mixed with the rinse fluid.

FIG. 8 is a left side view of the axial center vertical split of the 2 nd construction of the "single stage centrifugal pump with at least 2 discharge ports provided with a dividing wall of the liquid collecting and discharging flow path" according to the present invention.

Fig. 9 is an elevational view, in radial cross-section, of the main impeller of the centrifugal pump of fig. 8, taken along the center of the main impeller splitter plate 1901.

The pump structure shown in fig. 8 and 9 is different from the pump structure shown in fig. 5 only in that: the blade 14 of the main impeller 1 is provided with 1 main blade flow dividing partition plate 1901, the outer side part of the main impeller flow passage is divided into 2 sub-flow passage cavities (a sub-flow passage 14DA close to the front cover plate of the main impeller and a sub-flow passage 14DB close to the rear cover plate of the main impeller), the main blade flow dividing partition plate 1901 and the liquid collection and discharge cavity partition plate 21 are in the same plane, so that the liquid materials thrown out from the 2 sub-flow passage cavities 14DA and 14DB are endowed with a certain directional outward throwing speed, and the flushing oil is favorably prevented from escaping from the rear liquid collection and discharge

sub-flow passages

27B and 29B.

In fig. 9, 141 main impeller blades, 142 main impeller blades (located behind the main blade splitter plate 1901), 1901 is a main impeller splitter plate cross-section, 702 is a main impeller shaft sleeve cross-section, and 701 is a pump shaft cross-section.

FIG. 10 is an axial center vertically sectioned left side view of the "single-stage centrifugal pump with at least 2 discharge ports provided with a dividing wall of a liquid collecting and discharging flow path" of the invention in the 3 rd configuration.

The pump structure shown in fig. 10 differs from the pump structure shown in fig. 8 only in that: the diameters of the main impeller back shroud 16 and the back blades 19 are enlarged, and the entire washing liquid is directly discharged into the sub-discharge region DB formed by the liquid collecting/discharging partition plate 21 in the radial direction.

The outer edge of the main blade is positioned as in fig. 8 as shown in fig. 10, and does not radially extend into the sub drain region DB formed by the liquid collecting and draining partition 21.

FIG. 11 is an axial center vertically sectioned left side view of the 4 th construction of the "single-stage centrifugal pump with at least 2 discharge ports provided with a dividing wall of a liquid collecting and discharging flow path" according to the present invention.

The pump structure shown in fig. 11 differs from the pump structure shown in fig. 10 only in that: the diameter of the part of the main impeller blade close to the back cover plate is also enlarged, and the part radially extends into a sub liquid discharge area DB formed by the liquid collecting and discharging partition plate 21, so that liquid thrown out from a flow passage between the main blade flow dividing partition plate 1901 and the main impeller back cover plate 16 can directly enter the sub liquid discharge area DB.

As shown in fig. 11, the flow path between the main blade flow-dividing partition 1901 and the main blade shroud does not radially extend into the sub drain region DB formed by the drain collecting partition 21.

FIG. 12 is an axial center vertically sectioned left side view of the 5 th construction of the "single-stage centrifugal pump with at least 2 discharge ports provided with a dividing wall of a liquid collecting and discharging channel" according to the present invention.

The pump structure shown in fig. 12 differs from the pump structure shown in fig. 8 only in that: the back vanes 19 of the back cover plate of the main impeller, which are arranged in the grooves WC10, limit the volume of the back chamber of the main impeller, facilitate the flushing oil to fill the area and prevent the back chamber from accumulating impurities. While some or all of the back cover 18 may be mounted in the recess WC10, it is generally not advisable to mount the main impeller in the recess WC10, since the solid particles contained in the liquid thrown by the main impeller 1 will hit the body of the back cover 16 of the erosion pump.

The main impeller of the centrifugal pump can use an open impeller, namely an impeller rear cover plate and an impeller front cover plate.

The main impeller blade 14 of the centrifugal pump of the invention divides the baffle 1901, and can be on a plane with the baffle 21 of the liquid collecting and discharging cavity, for example, staggered; meanwhile, the blade dividing partition 1901 of the main impeller blade 14 may have a long radius of partial width and a short radius of partial width, and the radius of the inner ring of the collecting and draining fluid channel dividing partition is larger than the short radius of the main impeller blade and smaller than the long radius of the main impeller blade, that is, the blade dividing partition and the collecting and draining fluid channel dividing partition are overlapped when viewed along the pump shaft direction, so that the dividing and guiding effects are better. This is the case in fig. 10 and 11.

As shown in fig. 5, the inner edge 23 of the liquid collecting and discharging cavity partition plate 21 is circular, and in the operating state, the circular edge 23 is not in contact with the maximum outer edge of the main impeller 14; in the working state, the gap between the circular edge 23 and the maximum outer edge of the main impeller 14 is usually 0.5-3.0 mm.

As shown in fig. 5, the liquid collecting and draining chamber partition plate 21 is seamlessly connected or assembled with the pump shell 31, and the partition plate 21 is a solid non-leakage partition plate; the inner edge of the diaphragm 21 is generally circular and is in a plane perpendicular to and concentric with the pump shaft.

As shown in fig. 5, the inner side edge of the liquid collection and drainage cavity separation plate 21 is generally circular, and an edge line SPEC of an inner side section of the liquid collection and drainage cavity separation plate 21 after being split along the pump shaft center line is parabolic, and generally, a connection between the edge line SPEC and a main plate surface of the liquid collection and drainage cavity separation plate 21 is tangential.

As shown in fig. 5, in the liquid collecting and discharging passages DA and DB, guide vanes are attached to the side 2 of the liquid collecting and discharging chamber partition plate 21, and as necessary, the guide vanes may be attached only to one side or not.

As shown in fig. 5, in the liquid collecting and discharging flow passages DA and DB, at least 2 guide vanes, generally 3 to 6 guide vanes, are installed on one side of the liquid collecting and discharging chamber partition plate 21, and preferably, they are arranged at equal intervals along the circumference of the inner edge of the liquid collecting and discharging chamber partition plate 21.

As shown in fig. 5, one end of a certain guide vane of the liquid collecting and discharging cavity partition plate 21 is connected with the front cover or the rear cover of the pump, and the other end is connected with the surface of the liquid collecting and discharging cavity partition plate 21 for partition plate support or liquid discharging and flow guiding.

As shown in fig. 5, the shape of the guide vane disposed on the liquid collecting and draining chamber partition plate 21 is a streamline backward-bent vane when viewed along the flow direction of the fluid.

As shown in fig. 5, the liquid collecting and discharging chamber partition plate 21 can be clamped by the front cover and the rear cover of the pump and fixed by pins or screws, so that the mounting and dismounting are convenient.

As shown in fig. 5, the main impeller 1 is provided with back blades 19 of the impeller back shroud 16, and the back blades 19 may not be used as needed.

As shown in fig. 8, a flow dividing partition 1901 of the impeller 1 is provided at an outer section of the main blade 14 body of the main impeller 1 to divide the impeller 1 flow path into 2 sub-flow paths.

As shown in fig. 8, the dividing wall 1901 is positioned in one plane corresponding to the position of the dividing wall 21 provided in the liquid collecting/discharging flow path.

As shown in fig. 8, the flow dividing partition 1901 of the impeller 1 has an annular plate shape, and is located on a plane perpendicular to and concentric with the pump shaft.

In general, the outer edge radius of the flow dividing partition 1901 of the impeller 1 is the same as the maximum radius of the impeller 1, and the inner edge radius is 0.50 to 0.90 of the maximum radius of the impeller 1.

If necessary, a series flow gap may be disposed on the dividing partition LD-GB1 to allow the adjacent sub-channels to be connected in series to balance the pressure, and typically, the ratio of the flow area of the series flow hole to the cross-sectional area of the related sub-channel of the small channel is less than 0.02.

As shown in fig. 6, 27B is the rear collection/drainage guide area, 29B is the rear collection/drainage diversion area, the flow rate of the fluid 2P in NP9 is lower or the cross-sectional area is smaller, and even if the main medium is a high viscosity and high solid content fluid, the operation conditions are lower than the viscosity and low solid concentration of the fluid 1P in NP1 due to the dilution of the flushing oil, and the blockage is not easy, and certainly, the CXY is required not to cause the extraction phenomenon to the main medium, i.e., the mutual solubility is good.

The following describes the flushing oil flow path and the auxiliary impeller, stationary vanes that may be used.

FIG. 13 is a schematic view of a first flushing oil flow path of a centrifugal PUMP OLD-PUMP of conventional structure for conveying bottom oil residue of a vacuum fractionating tower KT for directly liquefying coal to generate oil by hydrogenation.

Fig. 14 is a partial enlarged view of the flushing oil flow path shown in fig. 13.

Fig. 13 shows an electric centrifugal pump with a sealed pump shaft, which uses a 1-stage impeller, a closed impeller or an open impeller, single-suction feeding, and an impeller cantilever support mode, wherein the pump shaft can be fixed with a motor shaft through an elastic pin type coupling.

In fig. 13, components similar to the dynamic seal of the expeller (expeller, stay vanes, back blades) are shown.

In fig. 13, 701 denotes a pump shaft; j21 is an auxiliary impeller cover plate, J22 is auxiliary impeller blades, J23 is an auxiliary impeller axial gap, and J24 is an auxiliary impeller radial gap; 3121 is pump cavity rear inner cover, 3122 is pump cavity rear outer cover; j42 is a fixed guide vane, J43 is a fixed guide vane liquid discharge flow gap which is an axial gap flow passage and is also a pump cavity flushing oil inlet flow passage J43; 311 is the pump chamber front cover; 14 is a main impeller blade; 16 is the back shroud of the impeller, 19 is the back vane (usually the radial back vane), J65 is the back vane axial clearance, J66 is the back vane radial clearance; 2729 is the flow path or radial gap of the main medium thrown out by the main impeller 1 and is connected with the existing volute flow path. The parts not shown in fig. 13 include a pump shaft seal, and a pump shaft mechanical seal is provided on the outside (the side away from the main impeller) of the sub-impeller J20 to prevent the main medium from leaking into the environment.

As shown in fig. 13, when the centrifugal PUMP OLD-PUMP of the conventional structure normally works, the pressurized main medium discharged from the final main impeller is liquefied oil residue containing about 50 wt% of solid particles and about 50 wt% of liquid phase components such as easily-coked asphaltene, and the liquefied oil residue passes through the radial gap 2729 and the volute flow channel, and then is discharged from the centrifugal PUMP OLD-PUMP through the pressurized main medium discharge port 9 and enters the conveying pipeline. Taking a coal hydrogenation direct liquefaction device with oil product yield of 100 ten thousand tons/year as an example, the typical operation conditions of the centrifugal PUMP OLD-PUMP are as follows: the temperature is 311 ℃, the inlet pressure is 0.093MPa, the outlet pressure is 1.50MPa, and the rated flow is 200 cubic meters per hour.

As shown in fig. 13, in order to prevent liquefied oil sludge containing solid particles and easily coking asphaltenes from entering the sealing parts of the mechanical seal, a flushing oil CXY and a flushing oil flushing path mechanism are used. The flushing oil is decompression wax oil which is wax oil at the bottom of a fractionating tower from oil generated by a hydrogen supply solvent hydrogenation stabilizing device, the normal working temperature is 120-150 ℃, the pressure of a flushing oil pipeline is 1.80MPa, and the CXY flow of the flushing oil is 500kg/h, namely 0.5 ton/h.

As shown in fig. 13, regarding the flow path of the flushing oil CXY, when the centrifugal PUMP OLD-PUMP normally operates, the external flushing liquid CXY enters the inlet region of the sub-impeller blade cavity through the flushing oil inlet, then enters the sub-impeller blade cavity, is energized by the sub-impeller blade, and is thrown out of the sub-impeller blade cavity into the sub-impeller radial gap J24 by centrifugal force, giving the flushing liquid a rotational speed to the sub-impeller blade rotating at a high speed along with the shaft 701; then, the flushing oil CXY leaving J24 turns to flow into the anti-rotation flow passage cavity of the fixed guide vane J42 to perform centripetal radial linear flow towards the pump shaft; the flushing oil CXY leaving the stay vane J42 turns to flow into the stay vane drainage flow gap J43 (axial flow channel) for flow parallel to the pump shaft; flushing oil CXY leaving J43 turns to flow into the inlet region of the blade cavity of the back blade 19, then enters the back blade cavity of the main impeller, is energized by the back blade 19, rotates with the shaft 701 at high speed, gives a rotating speed to flushing liquid, is thrown out of the back blade cavity under the action of centrifugal force, and enters the back blade radial gap J66; finally, the flushing oil CXY leaving the radial gap J66 of the back vane is mixed with the pressurized main medium in 2729 (radial gap or flow channel of the main impeller 1), and the pressurized main medium is discharged from the discharge port 9 of the centrifugal PUMP OLD-PUMP and enters the delivery pipe.

FIG. 15 is a schematic view of the flow path of the 2 nd flushing oil of the KT bottom oil residue of the vacuum fractionating tower for transferring the direct liquefaction produced oil by coal hydrogenation by using the centrifugal PUMP OLD-PUMP with the conventional structure.

The flushing oil CXY flow path shown in fig. 15 differs from the flushing oil flow path shown in fig. 14 in that: the stay vanes J42 are not provided so that the flushing oil CXY leaving J24 is diverted to flow into the gap between the expeller shroud J21 and the pump chamber rear inner cover 3121, flowing rotationally and radially closer to the pump shaft.

FIG. 16 is a schematic view of the 3 rd flushing oil flow path of a centrifugal PUMP OLD-PUMP of conventional structure for conveying bottom oil residue of a vacuum fractionating tower KT for directly liquefying coal to generate oil by hydrogenation.

The flushing oil CXY flow path shown in fig. 16 differs from the flushing oil flow path shown in fig. 15 in that: the back blades 19 of the main impeller are not arranged, so that the flushing oil CXY flows through the back pump cavity KV between the back cover plate 16 of the main impeller and the pump back covers 3121 and 3122, the energy is not increased basically, the function of generating centrifugal force is not provided, the solid particles possibly entering the back pump cavity KV are not thrown away, and the pressure in the central area of the back pump cavity is not reduced; in addition, the stability of the flow field of the flushing oil in the rear pumping chamber KV is poor, and a part of the pressurized main medium from the space 2729 may enter the outer annular region (near the radial gap space J66) of the rear pumping chamber KV and form a swirling flow.

Fig. 17 is a schematic view of the flushing oil flow path of a conventional centrifugal pump using a back pumping chamber flushing liquid.

As shown in fig. 17, no matter how the washing liquid enters the back pump cavity KV, the washing oil enters the washing oil CXY of the flow passage J43 through the back pump cavity, turns to flow into the inlet region of the blade cavity of the back blade 19, then enters the back blade cavity of the main impeller to be energized by the back blade 19, and is thrown out of the back blade cavity into the back blade radial gap J66 under the centrifugal force by the back blade 19 rotating at high speed along with the pump shaft 1 to impart the rotation speed to the washing liquid; finally, the flushing oil CXY leaving the radial clearance J66 of the back vane is mixed with the pressurized main medium in 2729 (main vane radial clearance or flow passage), and the pressurized main medium is discharged from the main medium discharge port 9 out of the centrifugal PUMP OLD-PUMP and enters the delivery pipe.

The present invention is generally provided with the back-vane 19, and the back-vane 19 may be omitted as required.

The invention can be implemented in many ways, and in principle, the structure should be as simple as possible, so as to facilitate manufacture, assembly, disassembly, and maintenance, and facilitate the discharge of solid particles that may enter the pump cavity KV after entering the main pump.

The driving machine matched with the centrifugal pump can be any suitable prime motor, for example, the driving machine can be a conventional motor needing a pump shaft sealing device, and can be a motor without a shaft seal.

In the piping system outside the centrifugal pump KPUMP, in the discharge piping system, a flow meter and a control valve are usually provided; the piping system, which communicates with the back pump chamber flushing liquid inlet BFN, is usually provided with a filter, a one-way valve.

Detailed Description

The pressure in the present invention refers to absolute pressure.

The concentrations of the components described in the present invention, when not particularly specified, are weight concentrations, i.e., mass concentrations.

The single-stage centrifugal pump KPUMP has the main impeller arranged in cantilever structure, single-stage and single-suction mode, so as to simplify the internal structure of the pump cavity.

The pump cavity shell Q10 of the centrifugal pump KPUMP mainly has the functions of installing a main impeller and forming a rear pump cavity so as to apply energy to a main medium flowing through and flush the rear pump cavity.

The pump cavity shell Q10 of the centrifugal pump KPUMP of the invention, together with other components such as a back pump cavity flushing system, a pump shaft mechanical sealing system and a pipeline system for feeding and discharging materials, form a closed system for conveying main media.

The pump cavity shell Q10 of the centrifugal pump KPUMP at least comprises a front pump cover 311 and a rear pump cover 312 which can be disassembled and assembled for installation and maintenance, a pump shaft extends into the pump cavity from an opening BZSRK in the middle of the rear pump cover 312, and a main impeller 1 is installed on the pump shaft of the inner part of the pump.

For the sake of convenience in installation and maintenance, the pump chamber housing Q10 of the centrifugal pump KPUMP of the present invention has the rear pump cover 312 divided into 2 or more parts, and the front pump cover 311 divided into 2 or more parts, thereby constituting a multi-part pump chamber housing Q10.

The pump cavity of the centrifugal pump KPUMP can be a cavity formed by a front pump cover and a rear pump cover, and can be a cavity formed by cavity pieces between the front pump cover and the rear pump cover as well as between the front pump cover and the rear pump cover.

In the pump cavity shell Q10 of the centrifugal pump KPUMP, guide vanes, a liquid inlet flow passage, a liquid discharge flow passage and the like can be installed according to requirements.

According to the pump cavity shell Q10 of the centrifugal pump KPUMP, part of the main impeller KS is sleeved on the pump shaft and extends into or passes through an opening BZSRK in the middle of the rear pump cover 312.

On the cavity wall of the pump cavity shell Q10 of the centrifugal pump KPUMP of the present invention, interfaces such as a pump shaft insertion port, a primary medium inlet 1FN, a pressurized primary medium discharge port 9 (at least 2), a rear pump cavity flushing liquid inlet, etc. are provided, and according to the needs, 1 or several of these interfaces are provided on the rear pump cover 312, and the remaining interfaces may be provided on the front pump cover 311.

In the cavity wall of the pump chamber housing Q10 or inside the pump housing of the centrifugal pump KPUMP, a flow path for pump feed or discharge (e.g. a discharge volute flow path) can be provided, facilitating free arrangement of the location of the external interface.

The back pump cavity KV of the centrifugal pump KPUMP of the present invention refers to a gap for flowing the flushing fluid CXY, which exists between the back pump cover 312 and the main impeller 1.

An important application of the centrifugal pump is to convey KT tower bottom oil residue of a vacuum fractionating tower for directly liquefying coal to generate oil by hydrogenation, and typical operating conditions are as follows: the temperature is 280-380 ℃, the solid concentration of the main medium is 45-55 wt%, and the asphaltene concentration of the main medium is 25-35 wt%.

When the centrifugal pump KPUMP is used for conveying slurry containing solids and asphaltine, an auxiliary impeller, a fixed guide vane and a back blade are generally used as flow path parts of back pump cavity flushing liquid to increase the safety of a pump shaft mechanical seal and a back pump cavity and prevent a main medium from entering the pump shaft mechanical seal through the back pump cavity to contact a sealing element.

In fig. 13, components similar to the expeller power seal (expeller, stay vanes, back vanes) are used and, therefore, the expeller power seal is described below with reference to fig. 13, except that the expeller power seal does not use a continuous injection of rinse liquid, but a shutdown seal is provided.

Since much of the monograph on the dynamic seal of the expeller is available and the details of the relevant information, the dynamic seal of the expeller will be described in detail below, which can be used as a reference for the present invention when using the same type of parts.

The dynamic seal of the auxiliary impeller, also known as hydrodynamic seal, is a non-contact radial seal with fixed clearance, it can overcome the deficiency of packing seal and mechanical seal, suitable for other sealed hard to be competent occasions, such as high speed, high temperature, transport medium with strong corrosivity or poisonous or suspended solid particle, especially when transporting the medium containing solid particle, can throw the solid particle off the shaft (or axle sleeve), protect the shaft (or axle sleeve) from wearing and tearing, therefore get the extensive application in the impurity pump, chemical slurry pump, become the basic configuration.

The auxiliary impeller power seal is a centrifugal force generated by the rotation of the liquid (or isolation liquid) leaked out of the main impeller driven by the auxiliary impeller, and the centrifugal force and the pressure of the leaked liquid reach pressure balance, so that the liquid is prevented from leaking. Thus, the expeller power seal is also known as a centrifugal seal or hydrodynamic seal.

The auxiliary impeller power seal is a rotary seal structure, generally comprises back blades, fixed guide blades, an auxiliary impeller, a parking seal and the like, and each part of the auxiliary impeller power seal is used as follows:

the back blade is a narrow blade which is arranged on the back cover plate (viewed along the fluid flow direction) of the radial impeller or the mixed flow impeller in the radial direction and can be used for balancing the axial thrust of the pump; for pumps for conveying fluid containing solid particles, such as slurry pumps, back blades play a role in reducing the pressure of a back cavity of the pump, balancing an impeller shaft and reducing the probability of impurity particles entering a shaft sealing device;

secondly, fixed guide vanes, also called anti-rotation vanes, play a role in eliminating liquid rotation, and are generally provided with radial guide vanes; when no fixed guide vane is arranged, the liquid on the light back side of the auxiliary impeller rotates at an angular speed of omega/3-omega/2 approximately, the pressure is distributed in a parabolic rule, and the pressure on the lower part (close to the central part) of the light back side of the auxiliary impeller is smaller than the pressure on the outer diameter part of the auxiliary impeller; the fixed guide vanes are arranged, so that liquid on the light back side of the auxiliary impeller can be prevented from rotating and flowing, the difference between the pressure on the lower part of the light back side of the auxiliary impeller and the pressure on the outer diameter of the auxiliary impeller is not large, namely, the pressure on the lower part (close to the central part) of the light back side of the auxiliary impeller is improved, and the plugging pressure of the auxiliary impeller is also improved;

and thirdly, the auxiliary impeller is actually a small centrifugal impeller, and high-pressure fluid at the outlet of the main impeller is sealed and leaked outwards (outside the mechanical seal of the shaft) by the pressure generated by the auxiliary impeller. When the pump is stopped, the auxiliary impeller does not work, so that the dynamic seal of the auxiliary impeller and the stop seal device need to be matched for use.

The structures of the back blade and the sub-impeller are described in detail below.

The back blade, its structural parameter can be any suitable parameter, usually make several open radial ribs on the back cover plate plane of the impeller, usually, its shape can adopt the radial straight blade or back bend blade like pump impeller; the number of the back blades is 4-16 blades, and the width of the blades is 5-10 mm; the clearance (back pump cavity clearance) size of back blade and pump case back wall is great to the performance influence, and the back pump cavity clearance value should be better more less on theory, but if back pump cavity clearance undersize, back blade easily causes the friction to generate heat and damages the part when the pump is in operation, so generally get, back pump cavity clearance than the blade width widen 0.3 ~ 3mm to guarantee that back blade freely rotates.

The structural parameters of the expeller, expeller vane can be any suitable parameters, and generally, the shape of the expeller vane is roughly 4:

firstly, forward bending blades (an inlet angle is more than 90 degrees);

secondly, the inlet part is inclined by an angle of 30 degrees and then is a radial straight blade;

thirdly, the impeller is a backward bending blade (the inlet angle is less than 90 degrees) like the main impeller of the pump;

the radial straight blades are generally backward bent blades or radial straight blades, the number of the blades of the moon wheel is 6-16, the width of the blades of the auxiliary impeller is 5-30 mm, and the sealing capacity can be improved by increasing the width and the number of the blades; the axial clearance between the auxiliary impeller blade and the side wall is usually 0.8-1.2 mm, the radial clearance at the outer edge of the auxiliary impeller is usually 1-1.3 mm, and the smaller the clearance, the better the sealing and pressing capacity is.

The use of the rear pump cavity flushing liquid has the following effects:

firstly, the pump cavity can be continuously washed, no outward leakage exists when the pump runs, no mechanical abrasion exists on the pump shaft, the reliability is high, and the service life is long;

the sealing device is suitable for sealing media under various harsh conditions, such as the sealing and conveying of media with high temperature, strong corrosion, solid particles and the like; the dynamic seal of the auxiliary impeller can prevent the leakage of toxic and harmful materials and reduce the environmental pollution;

thirdly, the main impeller back blade and/or the auxiliary impeller are/is used for dynamic sealing, some additional power is consumed, mainly on the friction loss between the auxiliary impeller and liquid, and the power needs to be increased by 2-15% under most conditions;

fourthly, based on the external flushing liquid pressure, the device is suitable for a wider pressure range;

the axial force of the auxiliary impeller can balance part of the axial force of the main impeller.

The back pump cavity flushing mode of the invention can combine the continuous injection of flushing liquid with the dynamic sealing of the auxiliary impeller, and essentially uses the uninterrupted updating of the media in the spaces such as the auxiliary impeller chamber, the fixed guide vane flow channel, the back blade chamber flow channel of the main impeller and the like by the flushing liquid, thereby fundamentally preventing the non-clean liquid from remaining in the spaces, ensuring the cleanness of the spaces, thoroughly preventing (blocking) the possibility that the non-clean liquid (the main medium conveyed by the main impeller) enters the pump shaft seal (such as a mechanical seal or a packing seal mechanism), ensuring the long-term safe operation of the pump shaft seal mechanism, and preventing the leakage of the non-clean liquid to the environment.

Since the conventional expeller power seal does not use a continuous injection of flushing fluid, but only sealing fluid, there is no loss problem of a large amount of continuous flushing oil, but the pump back cavity forms a relative flow dead zone.

When the invention continuously uses the continuous flushing liquid and the dynamic sealing parts (back blades, fixed guide blades and auxiliary impellers), the continuously injected flushing liquid is pressurized by the auxiliary impellers, then is input into the inner side of a back blade chamber of the main impeller through the fixed guide blades, and then is pressurized by the back blades of the main impeller and then is discharged out of a back pump chamber, so that a relative flow dead zone can be prevented from being formed in a back cavity of the pump.

Compared with the conventional auxiliary impeller power seal, the continuous flushing oil injection system is used for replacing a parking sealing mechanism, so that a large amount of flushing liquid is used due to the continuous flushing of the flushing liquid, the problem of recovering the flushing liquid is caused in order to reduce the loss amount of the flushing liquid, and the recovery mode of the flushing oil of the pump power seal is required to be changed correspondingly, so that the recovery mode is different from the conventional auxiliary impeller power seal (only a small amount of sealing oil is used, and continuous injection of the sealing oil is not required).

The power form (prime mover form) of the centrifugal pump of the present invention is not limited and may be any suitable form of drive machine. A

The centrifugal pump can be a centrifugal pump with a pump shaft sealed against the environment, and can be a centrifugal pump without a shaft seal.

Therefore, the pump cavity of the centrifugal pump KPUMP of the invention is a functional space for installing the main impeller for overflowing in the process of boosting the pressure of the process fluid main medium 1F, and guide vanes, flow channels and liquid discharge buffer spaces may be arranged in the pump cavity shell Q10 in a matching manner as required, and the pump cavity shell Q10 at least comprises a front pump cover and a rear pump cover.

The pump cavity shell Q10 of the centrifugal pump KPUMP can be divided into functional blocks (a front pump cover and a rear pump cover) according to requirements to form a combined structure which is convenient to disassemble and assemble, and at the moment, the pump cavity shell Q10 is a combined unit of 1 or 2 or more middle pump cavities among the front pump cover, the rear pump cover, the front pump cover and the rear pump cover.

The pump shaft seal of the invention refers to the seal of the centrifugal pump shaft to the external environment (not to the motor chamber), and is used for preventing the pumping main medium from leaking out of the pump group and entering the environment.

When the centrifugal pump disclosed by the invention uses a driving machine without a pump shaft seal, such as a motor without a shaft seal, the pump cavity shell Q10 rear pump cover can be the front end of a motor part, or the front end of a motor chamber, or the front end of a connecting body between the motor chamber and the pump cavity.

When the centrifugal pump is not a non-shaft seal pump set but a shaft seal pump set, a pump shaft sealing mechanism needs to be configured.

The impeller of the main pump of the present invention may be an impeller of any suitable configuration or shape.

The inlet of the impeller of the main pump of the centrifugal pump can be provided with guide vanes and can be provided with a homogenizing impeller or an emulsifying impeller or a homogenizer or an emulsifier for crushing slurry.

The invention is characterized in that the collection and discharge liquid cavity shunting partition plate is used for realizing the classified discharge of the main medium and the flushing liquid, and the collection and discharge liquid cavity shunting partition plate is used for mixing the main medium and the flushing liquid after partial pressure rise, thereby preventing the rest main medium and the flushing liquid from being mixed after the pressure rise, therefore, the collection and discharge liquid cavity shunting partition plate is also an anti-mixing partition plate or a limited flow mixing partition plate. Generally, precise control of the material flow discharged using the manifold divider of the manifold chamber is required, which requires piping to install flow control valves.

According to the centrifugal pump KPUMP, one or more of the auxiliary impeller J20, the fixed guide vane J42 and the main impeller back vane 19 can be arranged.

The pump cavity of the invention can be provided with external auxiliary components according to requirements, for example, when the pumped main medium is a main medium which has a low condensation point and is easy to solidify or has a rapidly increased viscosity after being cooled, the pump cavity is generally required to be provided with a heat-insulating jacket.

The arrangement mode of the centrifugal pump KPUMP can be any suitable arrangement mode, but a pump shaft vertical arrangement scheme is preferred.

To simplify the pump chamber structure, the pump shaft is preferably cantilevered and the pump shaft is preferably large in diameter to increase stiffness.

The CXY flushing fluid used in the centrifugal pump of the present invention is described in detail below.

The CXY flushing fluid used by the centrifugal pump is selected according to specific working conditions, but common basic requirements comprise no particle, the mixing of main media in the process, non-corrosiveness, non-toxicity, no environmental pollution, no extraction phenomenon caused to the main media, namely good intersolubility, and the best requirements comprise convenience, easiness in obtaining and convenience in recycling. Because the flushing fluid CXY is typically in contact with the rotating seal components of the pump shaft (e.g., mechanical seals, packing seals), it preferably has good lubrication properties. For a shaft seal-free centrifugal pump, because the flushing fluid CXY flows through the motor chamber, the flushing fluid CXY is also generally required to meet certain indexes such as insulation strength, volatile component content, condensation point, compatibility with a cable insulation material (deterioration due to no interaction), and the like, and the requirement at this time is more severe.

The centrifugal pump KPUMP is characterized in that a typical main medium is oil residue at the bottom of a vacuum fractionating tower KT, which is used for generating oil through direct coal hydrogenation liquefaction, residual oil suspension bed hydrocracking and residue oil boiling bed hydrocracking, at the moment, the operating conditions of a bottom oil residue conveying pump KPUMP of the vacuum fractionating tower KT can be any suitable operating conditions, and generally comprise the following steps: the temperature is 280-420 ℃, the inlet pressure is 0.04-0.099 MPaA, the outlet pressure is 0.5-3.5 MPaA, the weight concentration of solid particles is 0-65%, and the volume flow rate of liquid at the inlet of the pump cavity is 20-350 m³H is used as the reference value. In this case, the flushing fluid (flushing oil) is usually a medium wax oil and/or heavy diesel oil component, and the flow rate of the flushing fluid: typically 200-800 kg/hr of flushing oil is consumed per pump, typically 400-600 kg/hr of flushing oil is consumed per pump.

The centrifugal pump KPUMP is characterized in that a typical main medium is coal hydrogenation direct liquefaction with small flow, residual oil suspension bed hydrocracking, residue boiling bed hydrocracking to generate oil vacuum fractionating tower KT bottom oil residue, and at the moment, the operation condition of a KT bottom oil residue conveying pump KPUMP of the vacuum fractionating tower can be any suitable operation condition, and generally comprises the following steps: the temperature is 280-420 ℃ and the inlet pressure is 0.04 to 0.099MPaA, outlet pressure of 0.5 to 3.5MPaA, solid particle weight concentration of 0 to 65 percent and pump cavity inlet liquid volume flow rate of 0.1 to 20m³H is used as the reference value. In this case, the flushing fluid (flushing oil) is usually a medium wax oil and/or heavy diesel oil component, and the flow rate of the flushing fluid: typically 50-100 kg/hr of flushing oil is consumed per pump, typically 100-200 kg/hr of flushing oil is consumed per pump, it can be seen that the ratio of the flushing oil flow to the main medium flow is very large and the flushing oil losses are not tolerable.

The invention relates to a vacuum fractionating tower system KT-UNIT for generating oil by direct coal hydrogenation liquefaction, residual oil suspension bed hydrocracking and residual oil boiling bed hydrocracking, which is a separation system at least comprising a vacuum fractionating tower and is used for separating a vacuum distillation raw material based on generated oil into residue and distillation oil.

The vacuum fractionating tower system KT-UNIT provided by the invention can comprise a heating furnace F100-FUNR for fractionating a raw material F100, at the moment, at least one part of a material F100-FUNR-P discharged by the heating furnace F100-FUNR enters a fractionating tower KT, for example, all the F100-FUNR-P enters the fractionating tower KT, all the F100-FUNR-P is mixed with gas steam and then enters the fractionating tower KT, all the F100-FUNR-P enters the fractionating tower KT through steam obtained by a flash tank V10, and liquid phase obtained by a flash tank V10 enters a bottom oil residue conveying pump KPUMP of the vacuum fractionating tower KT for pressurization conveying.

The operating conditions of the KT-UNIT vacuum fractionator system may be any suitable operating conditions, typically: the temperature at the top of the tower is 280-420 ℃, the pressure at the inlet is 0.04-0.099 MPaA, the pressure at the outlet is 0.5-2.5 MPaA, the weight concentration of solid particles is 0-65%, and the volume flow rate of liquid at the inlet of the pump cavity is 0.1-150 m³H is used as the reference value. In this case, the flushing fluid (flushing oil) is usually a medium wax oil and/or heavy diesel oil component, and the flow rate of the flushing fluid: typically 200-800 kg/hr of flushing oil is consumed per pump, typically 400-600 kg/hr of flushing oil is consumed per pump.

The hydrocarbon material of the invention comprises hydrocarbon powder such as coal and hydrocarbon liquid such as inferior heavy oil.

The heavy hydrocarbon material at least comprises part of solid hydrocarbon powder (such as coal) and/or vacuum residue components.

The heavy hydrocarbon material comprises solid hydrocarbon powder (such as coal) or vacuum residue components.

The hydrogenation reaction process of the hydrocarbon material can be a direct coal hydrogenation liquefaction reaction process, an inferior heavy oil hydrogenation reaction process, a kerosene co-hydrogenation reaction process and an oil product hydrogenation reaction process.

The hydrogenation reaction process of the heavy hydrocarbon material can be a direct coal hydrogenation liquefaction reaction process, an inferior heavy oil hydrogenation reaction process, a kerosene co-hydrogenation reaction process and an oil product hydrogenation reaction process.

The hydrogenation reaction of hydrocarbon material in the invention refers to the hydrogenation reaction of liquid and/or solid such as oil and/or coal containing carbon and hydrogen elements under the condition of hydrogen existence and pressurization, the raw oil of the hydrogenation process of hydrocarbon oil is subjected to hydrofining and/or hydro-thermal cracking reaction to generate at least a part of products with lower molecular weight, and the raw coal of the hydrogenation direct liquefaction reaction process of coal is subjected to thermal swelling, primary pyrolysis, secondary thermal cracking of intermediate products, free radical hydrogenation stabilization, thermal condensation and other reactions to generate at least a part of hydrocarbon products with conventional boiling points lower than 450 ℃.

Typical examples of the hydrogenation reaction process of the hydrocarbon material of the invention are a high-temperature coal tar suspension bed hydrogenation deep refining reaction process, a medium-low temperature coal tar suspension bed hydrogenation thermal cracking reaction process, a coal hydrogenation direct liquefaction reaction process, an oil-coal co-refining hydrogenation reaction process, a petroleum-based heavy oil suspension bed or a fluidized bed hydrocracking reaction process.

The reaction product BASE-ARP of the hydrogenation reaction of the hydrocarbon material in the invention usually contains vacuum residue components and/or solid particles, and is usually at least a gas-liquid two-phase material flow, and most of the materials belong to a gas-liquid-solid three-phase material flow. The effluent ARP-X of the hydrogenation reaction is used for discharging a hydrogenation reaction product BASE-ARP, appears in the form of 1-path or 2-path or multi-path materials, and is a gas phase or liquid phase or gas-liquid mixed phase or gas-liquid-solid three-phase material flow.

The oil produced by the hydrogenation reaction of the hydrocarbon material refers to a product hydrocarbon component produced by the hydrogenation reaction of the hydrocarbon material, and the product hydrocarbon component may contain solid particles, soluble gas, light hydrocarbon and other components.

The shaft seal-free pump package is described in detail below.

The shaft seal-free pump set refers to a pump rotating shaft which is completely arranged in a closed container and is not exposed to the environment.

The shaft seal-free pump set KPUMP can be selected from one of a shielding electric centrifugal pump, a submerged electric centrifugal pump and a magnetic centrifugal pump.

The centrifugal canned motor pump of the invention refers to a canned motor driven centrifugal pump.

The invention relates to a canned motor pump, which is a non-shaft seal pump, wherein an impeller is sealed in a pressure container which is filled with pumped media and drives a motor rotor to be sealed in a special cooling and lubricating medium with similar operating pressure and essentially belongs to a communicating vessel, the pressure container is only statically sealed, and the motor stator provides a rotating magnetic field to drive the rotor. The structure cancels a dynamic sealing device of a rotating shaft of the traditional centrifugal pump to the environment, so the structure can completely avoid leakage and can be widely applied to the fields of refrigeration, air conditioning, medicine, chemical industry, petroleum and the like.

In the canned motor pump of the present invention, the impeller is usually installed at the outward extending end of the motor shaft (in the pump impeller cavity), and the impeller, the pump shaft and the motor rotor jointly form a rotating part. The impeller in the pump shell of the canned motor pump is coaxial with the canned motor rotor, and the basic components of the canned motor pump at least comprise a pump body, a canned motor and a connecting body for manufacturing, assembling and maintaining; when the connecting body is used, one end of the connecting body is in butt joint with a pump shell, the other end of the connecting body is in butt joint with a shielding motor, and a shaft of a rotor of the shielding motor penetrates through the connecting body and then enters the front end part in the pump shell to be used as a shaft for mounting a pump impeller.

The present invention relates to a non-shaft seal submersible electric centrifugal pump, generally refers to a centrifugal pump driven by a liquid immersion type electric motor, such as a non-shaft seal oil immersion type electric pump for conveying oil products and a non-shaft seal water immersion type electric pump for conveying boiler water, and is characterized in that a 'wet' stator is used, and a stator winding group is immersed in liquid. At present, manufacturers of shaft seal-free wet electric pumps in China include fertilizer-mixing and Wan electric motor technology development company with limited responsibility and the like.

The shaftless canned motor pump of the present invention is generally considered to have been developed after the advent of the shaftless submersible motor pump, and the difference between the shaftless canned motor pump and the shaftless submersible motor pump is the use of canned motors. Generally, the inner surface of a stator of a shielded motor is isolated by a non-magnetic corrosion-resistant sheet sleeve to form a stator shielding sleeve, the outer surface of a rotor of the shielded motor is isolated by a non-magnetic corrosion-resistant sheet sleeve to form a rotor shielding sleeve, and power (torque between the stator and the rotor) is transmitted from the stator to the rotor through a magnetic force field; the stator shielding sleeve and the rotor shielding sleeve are pressure containers in nature, the ends of the shields are statically sealed by flanges or welded structures, and are separated from the conveyed liquid, so that the stator winding iron core and the rotor iron core are not corroded, and the stator shielding sleeve and the rotor shielding sleeve are filled with resin possibly. The shield is made of a non-magnetic, corrosion resistant, high strength metal material, typically hastelloy (hastelloy c) alloy. At present, manufacturers of canned motor pumps in China include Hefei Hu canned motor pump company, Dalian empire national canned motor pump company, HAYWARDTYLER electric canned motor pump company, and the like.

The electric pump without shaft seal has various structural main part arrangement schemes due to the requirements of manufacturing, assembling and maintaining, and at least comprises the following 2 typical schemes:

the pump comprises a pump cover, a motor body without a shaft seal, a rear cover (or other substitute parts) of the motor without the shaft seal, a radial subdivision structure (also called non-subdivision) of a pump body part, and an independent circulating pump body part which only comprises the pump cover; the installation scheme is that the outlet and the inlet of the pump cover are butted with a process pipeline, and the structural part of the motor shell without the shaft seal, which is close to one end of the pump body, serves as the rest structural parts (the rear pump cover) of the pump shell;

the scheme of four structural main parts comprises a pump cover, a connecting body, a motor body without a shaft seal, a rear cover (or other substitute parts) of the motor without the shaft seal, a radial subdivision structure (also called as non-subdivision) of the pump body part, and one end of the connecting body is butted with the pump cover, and the other end of the connecting body is butted with the shielding motor body.

The electric pump without shaft seal according to the present invention may further comprise other auxiliary components such as an integrated cooler, as required.

The electric pump without shaft seal according to the present invention may further comprise other auxiliary components such as an auxiliary circulating pump for a cooler, if necessary, for example, the present invention may be used in combination with the "high temperature fluid-shielded electric pump system with emergency circulation function of main motor coolant" of the invention patent application No. 201710588184.1.

The electric pump without the shaft seal can be provided with a cooling part or a cooling system of the electric pump body without the shaft seal.

The electric pump without the shaft seal, the motor and the pump body can share one integral base.

The arrangement position of the auxiliary liquid FZL input system of the electric pump without the shaft seal can be at any suitable position of any suitable main part, and can be at any suitable position in a pump body (generally not a pump cover part) or a connecting body or a motor body without the shaft seal or a rear cover plate of a motor chamber or a part used as the rear cover plate of the motor chamber.

The arrangement position of the lubricating liquid (also cooling liquid) EL input system of the shaft seal-free motor cavity of the shaft seal-free electric pump can be at any suitable position of any suitable main part, and is usually at a suitable position in the shaft seal-free motor body and is usually at one end of the shaft seal-free motor body far away from the pump body.

The shaft seal-free electric pump can add a back blade on the back of the main impeller for a medium containing particles, and has the function of timely discharging solid particles to prevent the solid particles from accumulating; meanwhile, the axial unbalanced force can be reduced, the abrasion damage speed of the arranged thrust bearing is favorably reduced, and the service life of the thrust bearing is favorably prolonged.

When the overflowing medium of the shaft seal-free electric pump is a high-concentration solid liquid, a wear-resistant bushing or a wear-resistant shell can be used for prolonging the service life of the overflowing part of the pump cavity.

The shaft seal-free electric pump can be provided with the auxiliary impeller on the motor part to drive cooling liquid in the motor cavity to circularly work, and the axial force generated by the auxiliary impeller can be used for balancing the axial force generated by part of pump impellers because the auxiliary impeller is coaxial with the main impeller.

The mounting mode of the electric pump without the shaft seal can be vertical arrangement or horizontal arrangement.

The installation mode of the vertical electric pump without the shaft seal can be that the motor is positioned above and the pump body is positioned below, or the motor is positioned below and the pump body is positioned above.

According to the installation mode of the vertical electric pump without the shaft seal, the motor is positioned below the pump body, and the pump body is positioned above the motor, so that the gas in a cavity of the motor and the cavity of the pump can be discharged conveniently, and the gas accumulation can be prevented.

The impeller of the electric pump without the shaft seal is mainly in the form of a centrifugal pump impeller, the impeller can generate cavitation under certain working conditions, an inducer can be additionally arranged in front of the centrifugal impeller, and the cavitation erosion resistance of the pump is improved.

The electric pump without shaft seal can be combined with the technical proposal that a canned motor pump with two auxiliary liquid input systems is arranged under the application number of 201710063971.4.

The electric pump without shaft seal can combine the shielding motor of half-stroke external cooling chamber for the internal stator of the motor shell with application number 201710451303.9 and the technical proposal of the shielding electric pump.

The characteristic parts of the present invention are described below.

firstly, all the liquid does not enter a sub liquid discharge region NP9 space;

①K100＝0.50～1.00；

②K100＝0.30～0.50；

③K100＝0.20～0.30；

④K100＝0.05～0.20；

⑤K100＜0.05。

①K300＝0.50～1.00；

②K300＝0.30～0.50；

③K300＝0.20～0.30；

④K300＝0.05～0.20；

⑤K300＜0.05。

auxiliary liquid FZL which is flushing liquid CXY for the rear pump cavity KV;

firstly, horizontally arranging a pump shaft;

firstly, an erosion-resistant bushing;

② wear-resisting lining

Thirdly, corrosion-resistant lining;

fourthly, the thermal shock resistant bushing;

low temperature resistant lining.

firstly, an erosion-resistant bushing;

② wear-resisting lining

Thirdly, corrosion-resistant lining;

fourthly, the thermal shock resistant bushing;

low temperature resistant lining.

contains solid components;

② contains corrosive components;

③ containing a combustion component;

fourthly, toxic components are contained;

containing radioactive components;

sixthly, the volatile component is contained;

contains easily coagulated components;

eighthly, containing bubble liquid;

ninthly, high-temperature liquid;

low temperature liquid charge in the red cavity;

high-pressure liquid material.

④ the operation conditions of the main medium 1F conveyed by the centrifugal pump KPUMP are that the temperature is-150-650 ℃, the pressure is 0.1-40.0 MPa, and the volume flow rate of the main medium 1F is 0.1-10000 m³Per h, solid concentration of 0.01E50% by weight;

The invention has the advantages that:

the flushing oil and the main medium can be discharged in a classified manner, so that the discharging purity of the flushing oil and the main medium is improved, the flushing oil is recovered or reused, and the pollution degree of the main medium is reduced;

the improved part of the pump body has simple structure and is convenient to manufacture, overhaul and replace;

the device can reduce the loss of flushing oil (such as wax oil) by about 0.3-0.4 ten thousand tons per year and has obvious benefit for the device with the yield of the coal liquefaction oil of 100 ten thousand tons per year;

the device can be applied to a new device and can also be applied to the reconstruction of the existing device (namely, the replacement or reconstruction of the pump).

Examples

The yield of coal liquefaction oil is 108 ten thousand tons/year, a bottom oil residue delivery pump of a KT tower of a coal hydrogenation direct liquefaction reaction process for generating oil, the liquefaction residue consists of 50 wt% of asphaltene and 50 wt% of solids (catalyst, coal ash and unconverted carbon), flushing oil is mixed oil of heavy diesel oil components and wax oil components separated from the oil generated in the reaction process of a hydrogen supply solvent oil hydrogenation device, the scheme that the conventional flushing oil is mixed into the materials of the liquefaction residue is adopted according to the conventional oil residue delivery pump PAST-KPUMP working mode, and the device operation is 7600 hours/year, and each pump consumes 400-600 kg/hour of flushing oil, namely 3040-4560 tons/year.

By adopting the transfer pump of the invention, the impeller pump (without the guide vane 25 of the division plate of the liquid collecting and discharging cavity, the main impeller is an open impeller without a front cover plate) shown in figures 5 and 6 in the simplest structure is adopted, so that most 1F enters 1P, and a small part of 1F enters 2P; the impeller arrangement scheme is single-side cantilever type arrangement; the concentration of flushing oil in the discharged material 2P is 25 wt%, the concentration of liquefaction residues is 75 wt%, and the flushing oil and the liquefaction residues are returned to the feeding middle or discharging middle of a vacuum tower KT feeding heating furnace tube KFP or a vacuum tower KT flash evaporation section to be separated by pressure reduction flash evaporation; the flushing oil enters heavy diesel oil XP100 and side wax oil XP200 at the top of a distillate tower KT of the vacuum tower and is recovered; the heavy diesel oil XP100 and the side wax oil XP200 enter a hydrogenation device of the hydrogen supply solvent oil for cyclic reaction in the reaction process.

In this example, the main medium discharge 1P is used to deliver the vast majority of the liquefied residue 1F, which is essentially free of flushing oil.

Claims

1. Set up the single-stage centrifugal pump that collection flowing water runner reposition of redundant personnel baffle has 2 at least fluid-discharge ports, its characterized in that:

2. The single stage centrifugal pump of claim 1, wherein:

a flow dividing partition plate LD-GBX arranged in the collecting and discharging liquid flow channel V100 is connected or assembled with the pump cover in a seamless mode except for a material inlet, and the flow dividing partition plate LD-GBX is a solid leakage-free partition plate.

3. The single stage centrifugal pump of claim 1, wherein:

a flow dividing partition plate LD-GBX arranged in the collecting and discharging liquid flow channel V100 is connected or assembled with the pump cover in a seamless way except for a material inlet, and the flow dividing partition plate LD-GBX is a solid leakage-free partition plate;

the inner side edge of the flow dividing clapboard LD-GBX is in a ring shape, and the plane of the ring is vertical to the pump shaft.

4. The single stage centrifugal pump of claim 1, wherein:

the inner side edge of the flow dividing clapboard LD-GBX is in a ring shape, and the plane of the ring is vertical to and concentric with the pump shaft.

5. The single stage centrifugal pump of claim 1, wherein:

the whole inner side edge of the flow dividing partition plate LD-GBX is in a ring shape, and the inner side edge of the flow dividing partition plate LD-GBX is in a parabola shape after being divided along the central line of the pump shaft.

6. The single stage centrifugal pump of claim 1, wherein:

a flow dividing partition plate LD-GBX arranged in the collecting and discharging liquid flow channel V100 is connected or assembled with the pump cover in a seamless way except for a material inlet, and an entity leakage-free partition plate is arranged inside the collecting and discharging liquid flow channel V100;

the whole inner side edge of the flow dividing partition plate LD-GBX is in a ring shape, the circumference of the inner side edge of the flow dividing partition plate LD-GBX is not in contact with the maximum outer edge of the last-stage impeller KYL in a working state, and the gap between the circumference of the inner side edge of the flow dividing partition plate LD-GBX and the maximum outer edge of the last-stage impeller KYL is 0.5-3 mm.

7. The single stage centrifugal pump of claim 1, wherein:

a flow dividing partition plate LD-GBX is arranged in the liquid collecting and draining flow passage V100;

one side or 2 sides of the flow dividing clapboard LD-GBX are connected with the pump cover or other flow dividing clapboards through the guide vanes and are used for supporting or draining and guiding the flow of the flow dividing clapboard LD-GBX.

8. The single stage centrifugal pump of claim 1, wherein:

one side or 2 sides of the flow dividing partition plate LD-GBX are connected with the pump cover or other flow dividing partition plates through guide vanes LD-GBX-YP and are used as partition plates for supporting flow guiding or liquid drainage and flow guiding;

the number of the guide vanes LD-GBX-YP arranged on any side of the flow dividing partition plate LD-GBX is 2-6, and the shape of the guide vanes LD-GBX-YP is streamline backward bending vanes.

9. The single stage centrifugal pump of claim 1, wherein:

the splitter baffles LD-GBX are held by the pump front cover and the pump rear cover, possibly by pins or screws.

10. The single stage centrifugal pump of claim 1, wherein:

the outer section of the main blade 14 body of the main impeller 1 is provided with a main impeller flow dividing partition plate YL-GBX which divides the flow channel of the main impeller 1 into 2 or more sub-flow channels.

11. The single stage centrifugal pump of claim 1, wherein:

a main impeller flow dividing partition plate YL-GBX is arranged at the outer side section of the main blade 14 body of the main impeller 1 to divide a flow channel of the main impeller 1 into 2 or more sub-flow channels;

the main impeller flow dividing partition plate YL-GBX corresponds to the flow dividing partition plates LD-GBX arranged in the collecting and discharging liquid flow channel V100 one by one, and the main impeller flow dividing partition plate YL-GBX and the collecting and discharging liquid flow channel V100 flow dividing partition plate LD-GB which correspond to each other are in the same plane.

12. The single stage centrifugal pump of claim 10, wherein:

the main impeller flow dividing partition plate YL-GBX is in a circular ring shape, and the plane of the main impeller flow dividing partition plate YL-GBX is perpendicular to and concentric with the pump shaft;

the main impeller flow dividing partition plate YL-GBX has the outer edge radius which is the same as the maximum radius of the main impeller 1, and the inner edge radius which is 0.50-0.90 of the maximum radius of the main impeller 1.

13. The single stage centrifugal pump of claim 1, wherein:

the main impeller flow dividing clapboards YL-GBX correspond to the flow dividing clapboards LD-GBX arranged in the collecting and discharging liquid flow channel V100 one by one, and the number of the main impeller flow dividing clapboards YL-GBX is the same.

14. The single stage centrifugal pump of claim 1, wherein:

series flow gaps are arranged on the flow dividing partition plate LD-GBX arranged in the collecting and discharging liquid flow channel V100, and a small amount of liquid mixing of the adjacent sub-flow channels is allowed.

15. The single stage centrifugal pump of claim 14, wherein:

the flow dividing partition plate LD-GBX arranged in the collecting and discharging liquid flow channel V100 is provided with a series flow hole, so that the adjacent sub-flow channels are allowed to be mutually connected, and the ratio of the flow area of the series flow hole to the cross sectional area of the related small flow channel sub-flow channel is lower than 0.02.

16. The single stage centrifugal pump of claim 1, wherein:

the main impeller is an open impeller, and a rear cover plate is used without a front cover plate.

17. The single stage centrifugal pump of claim 1, wherein:

the inner side edge of a flow dividing partition plate LD-GBX arranged in the collecting and discharging liquid channel V100 is integrally in a ring shape CYC1, and the plane of the ring is vertical to and concentric with the pump shaft;

the outer part of the main blade 1 body is spatially related to the secondary drainage region NP9 and is selected from 1 of the following:

firstly, all the liquid does not enter a sub liquid discharge region NP9 space;

18. The single stage centrifugal pump of claim 1, wherein:

the back vanes 19 of the back shroud 16 of the main impeller 1, mounted in the recess WC10 of the pump back cover 312, limit the main impeller back chamber volume, facilitating the flushing oil to fill this area.

19. The single stage centrifugal pump of claim 1, wherein:

centrifugal pump KPUMP, contain 2 sub-runners in collection and discharge liquid runner V100: the ratio of the cross-sectional area S9 of the sub-flow passage NP9 to the cross-sectional area S1 of the sub-flow passage NP1 of the sub-flow passage NP9 close to the rear cover plate of the impeller and the sub-flow passage NP1 close to the front cover plate of the impeller is K100, K100 is (S9)/(S1), and the value of K100 is selected from 1 of the following components:

①K100＝0.50～1.00；

②K100＝0.30～0.50；

③K100＝0.20～0.30；

④K100＝0.05～0.20；

⑤K100＜0.05。

20. the single stage centrifugal pump of claim 1, wherein:

a flow dividing partition plate LD-GBX is arranged in the liquid collecting and discharging flow passage V100, an outlet pipe section of the liquid collecting and discharging cavity of the sub-set is transited into a circular pipeline in a mode that the internal section form is gradually changed, and a circular connector is used for being in butt joint with a pipeline system.

21. The single stage centrifugal pump of claim 1, wherein:

centrifugal pump KPUMP, contain 2 sub-runners in collection and discharge liquid runner V100: the ratio of the discharge flow rate W9 of the sub-flow channel NP9 to the discharge flow rate W1 of the sub-flow channel NP1 is K300, K300 is (W9)/(W1), and the value of K300 is 1 selected from the following:

①K300＝0.50～1.00；

②K300＝0.30～0.50；

③K300＝0.20～0.30；

④K300＝0.05～0.20；

⑤K300＜0.05。

22. the single stage centrifugal pump of claim 1, wherein:

in the centrifugal pump KPUMP, back blades 19 are provided on the plate surface of the side of the rear pump cover 16 of the main impeller 1 facing the pump rear cover.

23. The single stage centrifugal pump of claim 23, wherein:

centrifugal pump KPUMP, back vane 19 is a radial straight vane.

24. The single stage centrifugal pump of claim 1, wherein:

the flow path of the external flushing liquid CXY of the centrifugal pump KPUMP before being input into the rear pump cavity KV is selected from one of the following:

25. The single stage centrifugal pump of claim 1, wherein:

the prime mover at the drive end of centrifugal pump KPUMP is selected from 1 of the following:

26. The single stage centrifugal pump of claim 1, wherein:

centrifugal pump KPUMP uses an external drive, with a pump shaft mechanical seal system.

27. The single stage centrifugal pump of claim 1, wherein:

in the centrifugal pump KPUMP, at least one part of the pump shaft is exposed to the environment, and a pump shaft sealing system U80 for preventing the main medium from leaking to the environment is arranged on the pump shaft of the centrifugal pump.

28. The single stage centrifugal pump of claim 27, wherein:

a centrifugal pump KPUMP, wherein flushing liquid CXY flows through the auxiliary impeller and then enters a pump cavity shell Q10;

29. The single stage centrifugal pump of claim 1, wherein:

the centrifugal pump KPUMP is a shaft seal-free centrifugal pump and is selected from one of a shielding electric centrifugal pump, a submerged electric centrifugal pump and a magnetic centrifugal pump.

30. The single stage centrifugal pump of claim 1, wherein:

the centrifugal pump KPUMP is a shaftless electric centrifugal pump and is provided with an auxiliary liquid FZL input system;

auxiliary liquid FZL which is flushing liquid CXY for the rear pump cavity KV;

31. The single stage centrifugal pump of claim 1, wherein:

32. The single stage centrifugal pump of claim 1, wherein:

the arrangement mode of the centrifugal pump KPUMP is selected from 1 of the following modes:

firstly, horizontally arranging a pump shaft;

33. The single stage centrifugal pump of claim 1, wherein:

centrifugal pump KPUMP, inside pump chamber shell Q10 a chamber wall liner is arranged, the purpose of which is selected from 1 or several of the following:

firstly, an erosion-resistant bushing;

② wear-resisting lining

Thirdly, corrosion-resistant lining;

fourthly, the thermal shock resistant bushing;

low temperature resistant lining.

34. The single stage centrifugal pump of claim 1, wherein:

centrifugal pump KPUMP, the use of a liner arranged in the pump chamber housing Q10 on the inner wall of a liquid inlet pipe and/or a liner arranged on the inner wall of a liquid outlet pipe, selected from 1 or several of the following:

firstly, an erosion-resistant bushing;

② wear-resisting lining

Thirdly, corrosion-resistant lining;

fourthly, the thermal shock resistant bushing;

low temperature resistant lining.

35. The single stage centrifugal pump of claim 1, wherein:

the centrifugal pump KPUMP, main impeller inlet configuration inducer.

36. The single stage centrifugal pump of claim 1, wherein:

the centrifugal pump KPUMP has a pump shaft arranged in a single-side cantilever type manner.

37. The single stage centrifugal pump of claim 1, wherein:

the main medium conveyed by the centrifugal pump KPUMP is provided with 1 or more of the following media:

contains solid components;

② contains corrosive components;

③ containing a combustion component;

fourthly, toxic components are contained;

containing radioactive components;

sixthly, the volatile component is contained;

contains easily coagulated components;

eighthly, containing bubble liquid;

ninthly, high-temperature liquid;

low temperature liquid charge in the red cavity;

high-pressure liquid material.

38. The single stage centrifugal pump of claim 1, wherein:

the operating conditions of the centrifugal pump KPUMP are selected from 1 or more of the following:

39. The single stage centrifugal pump of claim 1, wherein:

the main medium 1F conveyed by the centrifugal pump KPUMP is oil residue at the bottom of a KT tower of a reduced pressure fractionating tower for directly liquefying R10 by hydrogenation of heavy hydrocarbon; the material discharged from the liquid collecting and discharging sub-flow passage NP9 closest to the rear cover plate of the impeller in the liquid collecting and discharging flow passage V100 of the conveying pump KPUMP is in a direction selected from 1 of the following types: