CN210565312U - Desulfurization circulating centrifugal pump for flue gas containing chloride ions - Google Patents

Abstract

The utility model discloses a desulfurization circulating centrifugal pump for containing chloride ion flue gas, including the pump body, lid around the pump body, closed metal impeller in the pump body, main shaft, motor, closed metal impeller is connected with the main shaft front end, and the main shaft passes the back lid and sets up the axle seal, and the motor is connected to the main shaft rear end, and closed metal impeller includes front and back width of cloth board, front and back width of cloth inter-plate impeller blade and set up in the impeller choma of preceding width of cloth board inlet department, and impeller choma inner chamber constitutes the passageway that overflows between the liquid outlet that forms to the impeller blade, overflows the passageway internal surface and has rolled and scribbled the plastic layer. The impeller is particularly suitable for large-scale plastic-lined centrifugal pumps with the flow rate of more than 2000m3/h, the service life of the impeller is 50-80% longer than that of the impeller in the prior art, the pump efficiency can be improved by 3-5%, and the manufacturing process is simple and convenient.

Description

Desulfurization circulating centrifugal pump for flue gas containing chloride ions

Technical Field

The utility model relates to a centrifugal pump preparation field especially relates to steel plant flue gas desulfurization is with anticorrosive wear-resisting pump, belongs to mechanical trade.

Background

In the flue gas desulfurization project of the steel plant, because the flue gas contains about 10 percent of calcium sulfate and a small amount of chloride ions, the service life of the common metal circulating spray centrifugal pump can be shortened due to the corrosion of the chloride ions. The impeller of the centrifugal pump made of 2205 dual-phase steel materials can be used for only 3-5 months generally, the flow channel part of the impeller can be corroded and abraded, the impeller blades are honeycombed, the honeycombed blades enable flowing slurry to generate vortex, the vortex generates flow resistance, the efficiency of the pump is reduced by 3-5%, and the service life of the impeller of the centrifugal pump is only 4-6 months due to the superposition of the corrosion and abrasion of the blades.

In order to solve the above problems, the utility model discloses the people is in the patent: ZL201510592190.5 discloses a desulfurization circulating spray centrifugal pump of steel lining ultra-high molecular weight polyethylene, and an impeller of the pump is made of ultra-high molecular weight polyethylene. The ultra-high molecular weight polyethylene is wear-resistant and corrosion-resistant, so that the problem of the desulfurization circulating pump for the flue gas containing chloride ions in iron and steel enterprises and coal chemical enterprises is basically solved.

However, the mechanical strength and rigidity of the ultra-high molecular weight polyethylene are inferior to those of stainless steel, and when the ultra-high molecular weight polyethylene is used for manufacturing an impeller with the flow rate of 2500m3/h and the lift of more than 30 meters, the blades of the centrifugal pump impeller are damaged by torsional deformation in the actual operation process. And the flow of a desulfurization circulating pump of a large-scale steel plant is required to be 3000-6000 m3/h, and a plastic impeller made of ultra-high molecular polyethylene cannot adapt to the condition due to low strength. Particularly, when the temperature of the spray liquid is higher than 70 ℃, the service life of the impeller is only 4-6 months. In order to solve the problem, a steel-lined ultra-high molecular polyethylene pump volute is matched with a stainless steel impeller to manufacture a desulfurization circulating pump for a steel plant with the flow rate of more than 3000m 3/h. However, the stainless steel metal impeller is corroded by chloride ions and by the scouring corrosion of calcium sulfate, and the service life of the stainless steel metal impeller is still only 4-6 months. In addition, in the later stage of use, the flow resistance of the fluid is increased due to abrasion and corrosion of the blade parts in the inner flow passage of the impeller or rough surfaces or honeycomb-shaped perforations, so that the operating efficiency of the pump is greatly reduced, and generally reduced from 76% to about 66%.

Therefore, the above-mentioned disadvantages still need to be improved.

SUMMERY OF THE UTILITY MODEL

The utility model discloses to prior art's is not enough, provide one kind and can be suitable for steel enterprise to carry chlorine-containing slurry and spray flue gas desulfurization technology, especially indicate that the flow moulds the centrifugal pump at the large-scale lining more than 2000m3/h, let impeller life than original technical length 50~80%, pump efficiency can promote 3~5%, and preparation simple process is convenient moreover, the desulfurization circulating centrifugal pump of price economy.

For realizing the purpose of the utility model, the following technical proposal is provided: the utility model provides a desulfurization circulation centrifugal pump for containing chloride ion flue gas, including the pump body, the pump body is the lid around, closed metal impeller in the pump body, the main shaft, a motor, closed metal impeller is connected with the main shaft front end, the main shaft passes the back lid and sets up the axle seal, the motor is connected to the main shaft rear end, its characterized in that closed metal impeller includes front and back width of cloth board, the impeller blade between front and back width of cloth board and set up the impeller choma in front width of cloth board inlet department, constitute the passageway that overflows between the liquid outlet that forms between impeller blade in impeller choma inner chamber, it has the plastic layer to overflow the interior surface roll-coating.

The blades of the impeller are twisted blades. The metal impeller is made of 2205, 904 or 316L.

Preferably, the flow passage comprises two side surfaces of the impeller blade and inner side surfaces of the front and rear webs of the impeller.

Preferably, the pump body and the front and rear covers of the pump body are both of plastic lining structures. The liner is preferably ultrahigh molecular weight polyethylene (UHMWPE), and more preferably ultrahigh molecular weight polyethylene (UHMWPE) having a molecular weight of 500 ten thousand or more.

Preferably, the inner attack angle and the outer wrap angle of the impeller blades are coated with a plastic layer. In the desulfurization application station, the key areas of abrasion damage of the impeller are the inner attack angle of the impeller blade and the outer attack angle of the impeller blade. The internal attack angle is severely eroded by the impact on the impeller blades caused by the redirection of the fluid as it enters the impeller. The abrasion of the outer wrapping angle of the impeller blade is mainly caused by that slurry is output from a liquid outlet of the impeller and collides with the inner wall of a volute of the pump, and then the backflow impacts the outer wrapping angle of the impeller, so that the outer wrapping angle of the impeller is abraded or corroded in an overlapping manner. The surface of the inner attack angle and the outer attack angle of the impeller blade is coated with a plastic layer, which not only solves the corrosion problem, but also overcomes the abrasion problem.

In order to increase the adhesive force of the coating on the flow channel in the impeller, the inner wall of the metal impeller can be subjected to sand blasting and polishing treatment.

Preferably, the inner attack angle surface is provided with an anchoring hole. The arrangement enables the plastic coatings on the two sides of the blade to be coupled through the holes, thereby playing the role of anchoring for preventing falling off.

Preferably, the ring of the impeller eye is provided with an annular groove or an anchoring hole. The plastic coating is tightly sealed with the metal impeller suction inlet, and the plastic layer of the impeller suction inlet is prevented from peeling or curling due to fluid washing.

Preferably, the thickness of the plastic layer is 1-5 mm, preferably 2-3 mm.

Preferably, the plastic layer is ultra-high molecular weight polyethylene.

The utility model discloses beneficial effect:

1. the defects that the full-plastic impeller of the large-scale plastic-lined desulfurization circulating centrifugal pump is poor in mechanical strength, easy to deform and short in service life are overcome.

2. The service life of the metal impeller in a desulfurization circulating pump in the steel industry is prolonged by 60%, and the conveying efficiency of the pump is improved by about 3-5%.

Drawings

FIG. 1 is a schematic structural view of a corrosion-resistant and wear-resistant pump of the present invention;

FIG. 2 is a schematic structural view of a plastic coated metal impeller according to the present invention;

FIG. 3 is an enlarged view of a portion A of FIG. 2;

FIG. 4 shows another embodiment of FIG. 3;

fig. 5 is a left side view of the metal impeller of fig. 2.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

Example 1:

as shown in fig. 1-5, a desulfurization circulating centrifugal pump for flue gas containing chloride ions comprises a pump body 1, a front cover and a rear cover 2 and 3 of the pump body, a closed metal impeller 4 in the pump body 1, a main shaft 5 and a motor 9, wherein the closed metal impeller 4 is connected with the front end of the main shaft 5, the main shaft 5 penetrates through the rear cover 3 and is provided with a shaft seal 6, the main shaft 5 is arranged on a bearing bracket 7 and is connected with the motor 9 through a coupler, the devices are arranged on a base 8, the closed metal impeller 4 comprises a front web 4.4, a rear web 4.5, an impeller blade 4.3 between the front web 4.4 and the rear web 4.5 and an impeller opening ring 4.2 arranged at liquid inlets of the front web 4.4 and the rear web 4.5, an overflowing channel is formed between an inner cavity of the impeller opening ring 4.2 and a liquid outlet formed between the impeller blades 4.3, and the inner surface. The flow passage comprises two side surfaces of the impeller blade 4.3 and inner side surfaces of the front and rear diaphragms 4.4 and 4.5 of the impeller.

The inner attack angle 4.3.1 and the outer attack angle 4.3.2 of the impeller blade 4.3 are coated with a plastic layer 4.1.

The surface of the inner attack angle 4.3.1 is provided with an anchoring hole 4.3.3.

An annular groove or an anchoring hole 4.2.1 is arranged on the inner ring of the impeller opening ring 4.2.

The manufacturing process comprises the following steps:

the pump casing 1, the pump front cover 2 and the pump rear cover 3 are molded and machined according to a lining plastic compression molding process of a conventional steel lining ultra-high molecular weight polyethylene centrifugal pump, other main shafts 5, bearing seats 7 and other components are manufactured according to a conventional machining method, and the impeller 4 is manufactured by the following method: machining a cast 2205 duplex stainless steel impeller blank to a required size by using a machining method, drilling a plurality of holes 4.3.3 with the diameter of 5mm at the inner punching angle part of an impeller blade, then forming a groove 4.2.1 at the impeller opening ring part, and further forming a plurality of holes with the diameter of 4-5 mm at the groove part, further removing burrs from an inner cavity flow channel of the impeller, and performing sand blasting and texturing treatment for later use.

Preparing plastic layer fine powder for later use, wherein the implementation method comprises the steps of taking 500 ten thousand molecular weight ultra-high molecular weight polyethylene powder, carrying out modification granulation, grinding the modified granular ultra-high molecular weight polyethylene into fine powder of 60-80 meshes by using a water-cooled mill, adding 0.3% of sodium salt and 0.2% of lithium salt into the fine powder, and fully mixing the fine powder for later use. Then put the metal impeller in the heating furnace and heat to 330 ℃, take out and cool to 310 ℃, scatter the above-mentioned plastics furfurescence and melt in the position that needs the plastic-coated, let it flow flat cool off by oneself, remove the burr, can obtain the metal impeller of runner inner chamber plastic-coated, reuse the conventional centrifugal pump mounting method and will line up with the plastic pump case 1, line with plastic front pump cover 2, line with plastic rear pump cover 3, main shaft 5, the impeller 4, bearing frame 7, mechanical seal 6, base 8, motor 9 that moulds in the runner are installed together, just obtained the desulfurization circulating centrifugal pump in the utility model.

The thickness of impeller inner runner plastic-coated is controlled to be more suitable at 2-3 mm in this embodiment.

In this embodiment, the ultrahigh molecular weight polyethylene (UHMWPE) is selected to improve the wear resistance of the plastic coating in the impeller, and is suitable for transporting corrosive slurry with high solid content, large particle diameter, and high wear resistance requirement.

The utility model discloses in through changing the formula of roller coating plastics, through promotion coating adhesive force and wearability, again through setting up hole or recess on the blade of impeller and sunction inlet ring, little improvement such as anchor plastic layer, scribble the runner of metal impeller with conventional plastic-coated technology in wear-resistant plastic layer heat, seem to be some little leather that changes, but played the life 60~80% of extension large-scale desulfurization circulating pump impeller really, the obvious efficiency of 3~5% of elevator pump delivery efficiency, and only need increase a small amount of manufacturing cost, there is fabulous input-output ratio, really play the effect that little improvement produced big benefit, the quality level of iron and steel trade desulfurization pump operation has been promoted, and then the environmental protection equipment level of iron and steel trade is promoted.

The described embodiments are only some, but not all embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Claims (8)

1. The utility model provides a desulfurization circulation centrifugal pump for containing chloride ion flue gas, including the pump body, the pump body is the lid around, closed metal impeller in the pump body, the main shaft, a motor, closed metal impeller is connected with the main shaft front end, the main shaft passes the back lid and sets up the axle seal, the motor is connected to the main shaft rear end, its characterized in that closed metal impeller includes front and back width of cloth board, the impeller blade between front and back width of cloth board and set up the impeller choma in front width of cloth board inlet department, constitute the passageway that overflows between the liquid outlet that forms between impeller blade in impeller choma inner chamber, it has the plastic layer to overflow the interior surface roll-coating.

2. The centrifugal pump for desulfurization circulation of flue gas containing chloride ions according to claim 1, wherein the flow passage comprises both side surfaces of the impeller blades and inner side surfaces of the front and rear webs of the impeller.

3. The desulfurization circulating centrifugal pump for flue gas containing chloride ions as claimed in claim 1, wherein the pump body, the front cover and the rear cover of the pump body are both plastic-lined structures.

4. The centrifugal pump for desulfurization circulation of flue gas containing chloride ions according to claim 1, wherein the inner attack angle and the outer attack angle of the impeller blades are coated with plastic layers.

5. The centrifugal pump for desulfurization circulation of flue gas containing chloride ions according to claim 4, wherein the inner attack angle surface is provided with anchoring holes.

6. The centrifugal pump for desulfurization circulation of flue gas containing chloride ions according to claim 1, wherein the ring of the impeller eye is provided with a ring-shaped groove or an anchoring hole.

7. The desulfurization circulating centrifugal pump for flue gas containing chloride ions as claimed in claim 1, wherein the thickness of the plastic layer is 1-5 mm.

8. The centrifugal pump for desulfurization circulation of flue gas containing chloride ions according to claim 1, wherein the plastic layer is ultra-high molecular weight polyethylene.

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