CN116328457B

CN116328457B - Fly ash pulping water washing process and pulping water washing equipment

Info

Publication number: CN116328457B
Application number: CN202310281392.2A
Authority: CN
Inventors: 陈伟杰; 龚代高; 陈成广
Original assignee: Zhejiang Yinuo Environmental Protection Group Co ltd
Current assignee: Zhejiang Yinuo Environmental Protection Group Co ltd
Priority date: 2023-03-16
Filing date: 2023-03-16
Publication date: 2023-12-19
Anticipated expiration: 2043-03-16
Also published as: CN116328457A

Abstract

The invention discloses a fly ash pulping water washing process and pulping water washing equipment, which relate to the technical field of environmental protection and comprise the following steps: pulping: raw material fly ash and water are put into a pulping tank and mixed to form fly ash slurry; pH neutralization: introducing the fly ash slurry into a pH neutralizing tank, adding hydrochloric acid into the neutralizing tank, and neutralizing the pH value of the fly ash slurry; and (3) centrifugal dehydration: the pH-neutralized and adjusted fly ash slurry is subjected to centrifugal dehydration treatment, so that water in the fly ash and fly ash particles can be separated from each other to obtain filtrate and fly ash filter residues; and (3) water washing treatment: putting the fly ash filter residue obtained by centrifugal dehydration into a washing stirring tank, adding a detergent, and diluting the filtrate residue in the fly ash filter residue; and obtaining the fly ash after washing by centrifugal separation. The invention can eliminate most pollutants in raw material fly ash by water washing to obtain relatively clean fly ash, thereby greatly reducing secondary pollution generated in the subsequent recycling process of the fly ash.

Description

Fly ash pulping water washing process and pulping water washing equipment

Technical Field

The invention relates to a fly ash treatment device, in particular to a fly ash pulping water washing process, a fly ash pulping water washing device and a centrifugal dehydration device for the fly ash pulping water washing treatment.

Background

Fly ash is a particle formed in the current industrial production process, is a common solid pollutant at present, and because the fineness of the fly ash is extremely fine, the surface of fly ash particles is smooth, most of the fly ash particles are spherical, and the fly ash particles are poorly bonded with other particles and cannot be directly mixed into building materials for recycling. There is a fly ash treatment method in which fly ash particles are fused to form a glass body by fusion and calcination treatment of fly ash, and then a new material which can be reused is obtained by centrifugal processing treatment.

For example, chinese patent publication No. CN113701163a discloses a high-temperature melting treatment system for fly ash, which comprises a melting system, a feeding system and an exhaust gas treatment system, wherein the melting system comprises a melting furnace, the lower part of the melting furnace is provided with a water-cooling fence, the upper part of the water-cooling fence is a melting section, the lower part of the water-cooling fence is a combustion section, the bottom of the melting furnace is provided with a slag groove, one side of the slag groove is provided with a melting liquid outlet groove with an overflow groove, and the slag groove and the melting liquid outlet groove are communicated through a liquid outlet hole; the outer side of the combustion section is provided with a plurality of annular arrays of natural gas nozzles, and the natural gas nozzles are obliquely downward and eccentrically arranged; the upper part of the melting furnace is provided with a flue pipe and a feed inlet. The fly ash is melted and calcined at high temperature to burn the material to form molten glass, and then the molten glass is recycled, so that the fly ash waste can be processed to form rock wool material, and further the recycling of the fly ash can be realized.

The fly ash can be recycled through calcination treatment, so that recycling is realized. Some harmful substances are often mixed in fly ash raw materials; in the calcination process, harmful pollutants in the fly ash enter the waste gas to form harmful waste gas pollution, and secondary pollution is generated if the calcination treatment is directly carried out. Moreover, some of the harmful contaminants, such as heavy metal contaminants, will also be deposited in the final product, affecting the safety of the secondary processing of the fly ash.

There is therefore a need to propose a new solution to this problem.

Disclosure of Invention

The invention aims to solve the problems and provide a fly ash pulping water washing device, which can eliminate most pollutants in raw material fly ash by water washing to obtain relatively clean fly ash, thereby greatly reducing secondary pollution generated in the subsequent recycling process of the fly ash.

The technical aim of the invention is realized by the following technical scheme: the fly ash pulping water washing equipment comprises a raw ash bin, a pulping tank, a neutralization tank, centrifugal dehydration equipment, a water washing fly ash bin and an adjusting tank, wherein the centrifugal dehydration equipment comprises a barrel and a rotating shaft, the barrel is horizontally arranged, and the rotating shaft and the barrel are coaxially arranged and penetrate through two ends of the barrel; the rotary seat I and the rotary seat II are respectively fixed at the positions corresponding to the two ends of the cylinder body on the periphery of the rotary shaft, and are both in rotary connection with the cylinder body and keep the cylinder body sealed; the periphery of the rotating shaft is provided with a first spiral blade corresponding to the position in the cylinder body, and the first spiral blade is used for spiral pushing of materials when the rotating shaft rotates; the inner periphery of the middle section of the rotating shaft is provided with a hollow separation cavity, and the outer periphery of the separation cavity is provided with a through hole communicated with the inner cavity of the cylinder; the inner part of the rotary seat I is provided with a water outlet cavity, the rotary seat I is provided with a water outlet hole communicated with the water outlet cavity, and the axis of the rotary shaft is provided with an inner hole communicated with the separation cavity and the water outlet cavity; the inner hole is internally provided with a feeding pipe, the feeding pipe extends out from one end of the rotating shaft, and the other end of the feeding pipe is a feeding end and extends into the separation cavity.

The invention is further arranged that one end of the second rotating seat extends into the cylinder, an annular cavity is formed at one end of the second rotating seat extending into the cylinder, the annular cavity is communicated with the inner cavity of the cylinder, and a discharging hole communicated with the annular cavity is formed in the periphery of the second rotating seat.

The invention is further arranged that the position, corresponding to the separation cavity to the annular cavity, of the rotating shaft is also in a hollow structure and is provided with a return channel, and the position, corresponding to the annular cavity, of the rotating shaft is provided with a return hole which is communicated with the annular cavity and the return channel.

The invention is further arranged that the feed back channel is provided with a central shaft which is coaxially arranged, and the central shaft extends into from the end part of the rotating shaft and penetrates through the feed back channel; the central shaft is kept fixed by an external bracket; and a second helical blade is arranged between the inner periphery of the return channel and the central shaft, the outer periphery of the second helical blade is fixed with the inner peripheral wall of the return channel and is separated from the central shaft, and the rotation direction of the second helical blade is opposite to that of the first helical blade and is used for pushing materials towards the direction of the separation cavity.

The invention is further arranged that the separation cavity is communicated with the inner hole and gradually reduces towards the inner hole; and a horn mouth I is formed between the separation cavity and the inner hole, and the horn mouth I gradually expands towards the direction of the separation cavity.

The invention is further arranged that the separation cavity is communicated with the return channel and gradually reduces towards the direction of the return channel; a horn mouth II is formed between the separation cavity and the return channel, and the horn mouth II gradually expands towards the direction of the separation cavity; the feeding end of the feeding pipe extends to the inner side of the bell mouth II.

The invention is further arranged that a valve assembly is arranged in the annular cavity, the valve assembly comprises a first annular sleeve and a second annular sleeve, and the first annular sleeve is sleeved on the periphery of the rotating shaft and is driven by a telescopic rod to axially and reciprocally adjust; the second annular sleeve is sleeved on the periphery of the first annular sleeve, and the periphery of the second annular sleeve is opposite to the position of the discharge hole and is used for opening and closing the discharge hole; and a spring is elastically pressed between the first annular sleeve and the second annular sleeve and is used for elastically supporting the second annular sleeve towards the middle section direction of the rotating shaft.

The invention is further arranged that the inner periphery of the first annular sleeve and the outer periphery of the rotating shaft are mutually propped, and the first annular sleeve extends towards the middle section of the rotating shaft and forms a sealing section; the inner periphery of the sealing section is propped against the outer periphery of the rotating shaft and is used for propping and sealing the feed back hole; the periphery 4 of the sealing section is provided with a material guiding hole, and when the material guiding hole is opposite to the material returning hole, the annular cavity is communicated with the material returning hole; when the guide hole and the return hole are staggered, the sealing section cuts off the return hole and cuts off the annular cavity and the return channel.

The invention is further arranged that the feed back hole is closer to the middle section of the rotating shaft relative to the discharge hole; the annular sleeve I is provided with a contraction position and an extension position; the first annular sleeve is positioned at the contraction position, the material guide hole and the material return hole of the first annular sleeve are staggered, the outer peripheral surface of the second annular sleeve is used for propping and closing the material outlet, the second annular sleeve can be elastically adjusted towards the direction deviating from the middle section of the rotating shaft, and the material outlet can be opened; the first annular sleeve is positioned at the extending position, and the second annular sleeve moves towards the middle section of the rotating shaft; the material guide hole is opposite to the material return hole, the outer peripheral surface of the annular sleeve II presses the material outlet to be closed, and the annular sleeve II always keeps the material outlet separated from the cylinder in the elastic adjustment process.

The invention also improves a fly ash pulping and washing process, and adopts the fly ash pulping and washing equipment to process; the method comprises the following steps:

pulping: raw material fly ash and water are put into a pulping tank and mixed to form fly ash slurry;

pH neutralization: introducing the fly ash slurry into a pH neutralizing tank, adding hydrochloric acid into the neutralizing tank, and neutralizing the pH value of the fly ash slurry;

and (3) centrifugal dehydration: the pH-neutralized and regulated fly ash slurry is subjected to centrifugal dehydration treatment, and the water in the fly ash and fly ash particles can be mutually separated through high-speed centrifugal rotation, so that filtrate and fly ash filter residues are obtained;

and (3) water washing treatment: putting the fly ash filter residue obtained by centrifugal dehydration into a washing stirring tank, adding a detergent, and diluting the filtrate residue in the fly ash filter residue; and then separating and treating the fly ash slurry by using centrifugal dewatering equipment to obtain the fly ash after washing.

In summary, the invention has the following beneficial effects:

by the fly ash pulping and washing industry, the fly ash can be washed, and most of pollutants in raw fly ash enter filtrate. And then, carrying out dehydration treatment on the fly ash slurry through centrifugal dehydration equipment to obtain filtrate and filter residues, and separating fly ash particles from the filtrate containing most pollutants. And the subsequent fly ash filter residues are subjected to repeated circulation treatment, so that pollutant residues in the fly ash filter residues can be further eliminated, relatively clean fly ash is obtained, and secondary pollution generated in the subsequent repeated utilization process of the fly ash is greatly reduced.

For the fly ash, since the particle fineness of the fly ash is extremely fine, if the fly ash slurry is directly filtered, the filter screen is easily blocked, the separation efficiency of the fly ash slurry is affected, and the filter screen needs to be frequently replaced and maintained. The separation of the fly ash filter residue and the filtrate of the fly ash slurry can be effectively realized by carrying out centrifugal separation treatment on fly ash particles in centrifugal dehydration equipment, and the adverse effect of filter screen blockage can be eliminated without adopting a filter screen for separation in the separation process, so that a stable and effective separation effect is realized; in addition, in the separation process, the fly ash filter residue can be circulated, and the washing treatment can be simultaneously carried out in the centrifugal separation process by matching with the input washing liquid, so that the cleanliness of the finally output fly ash filter residue is improved.

Drawings

FIG. 1 is a schematic diagram of a water washing process for pulping fly ash according to the present invention;

FIG. 2 is a schematic diagram of a water washing process for pulping fly ash according to the present invention;

FIG. 3 is a schematic diagram of a centrifugal dewatering device for water washing treatment of fly ash pulping according to the present invention;

FIG. 4 is a schematic diagram II of a centrifugal dewatering device for water washing treatment of fly ash pulping according to the present invention;

FIG. 5 is a schematic view of the structure of the separation chamber of the present invention;

FIG. 6 is a schematic view of a first end of the shaft of the present invention;

FIG. 7 is a schematic view of a second end of the shaft according to the present invention;

FIG. 8 is an enlarged view of FIG. 7 at A, illustrating the configuration of the valve assembly in the contracted position;

fig. 9 is a configuration of the extended position of the valve assembly of the present invention.

Reference numerals: 1. a cylinder; 101. a first end; 102. a second end; 103. a necking section; 2. a rotating shaft; 201. an inner bore; 202. a separation chamber; 203. a through hole; 204. a horn mouth I; 205. a horn mouth II; 206. a feed back channel; 207. a feed back hole; 3. a second rotating seat; 31. rotating the second sealing element; 32. an annular cavity; 33. a discharge hole; 34. a valve assembly; 341. the first ring is sleeved; 342. an annular sleeve II; 343. a telescopic rod; 344. a material guiding hole; 345. a sealing section; 346. a spring; 347. sealing the sliding sleeve; 348. an outer peripheral surface; 349. a first bump; 3410. a second bump; 4. a rotating seat I; 41. rotating the first sealing element; 42. a water outlet cavity; 43. a water outlet hole; 5. a bearing seat; 6. a first helical blade; 7. a feed pipe; 71. a feed end; 8. a central shaft; 9. and a second helical blade.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The embodiment discloses a fly ash pulping water washing device, which is shown in figure 1, and comprises a raw ash bin, a pulping tank, a neutralization tank, a centrifugal dehydration device, a water washing fly ash bin and an adjusting tank. Wherein the raw ash bin is used for storing fly ash raw materials. The pulping tank is used for mixing fly ash with water, and processing raw material fly ash into fly ash slurry by stirring and mixing. The neutralization tank is used for temporarily storing the processed fly ash slurry, and hydrochloric acid reagent with proper concentration can be added into the neutralization tank to adjust the pH concentration of the fly ash slurry, and the pH of the fly ash slurry is adjusted to be close to neutral or slightly acidic according to the requirement. The centrifugal dehydration equipment plays a role in dehydration treatment of the fly ash slurry, and can separate the water in the fly ash and the fly ash particles from each other through high-speed centrifugal rotation to obtain filtrate and fly ash filter residues. The water-washed fly ash bin is used for temporarily storing the water-washed fly ash. The regulating tank is used for temporarily storing the centrifugally separated filtrate, eliminating pollutants in the filtrate through proper reagents and recycling the components in the filtrate, and the specific regulating method is not related to the improvement points of the invention and is not described in detail.

If the fly ash raw material is directly calcined to generate secondary pollution, the fly ash is required to be washed with water, on the one hand, the alkaline pollutants in the fly ash are eliminated through acidity, and meanwhile, heavy metal pollutants and other pollutants mostly enter the filtrate. And then, carrying out dehydration treatment on the fly ash slurry through centrifugal dehydration equipment to obtain filtrate and filter residues, and separating fly ash particles from the filtrate containing most pollutants. Meanwhile, in the centrifugal dehydration treatment process, the filter residues of the fly ash particles are further subjected to water washing treatment through washing liquid, so that the cleanliness of the finally obtained fly ash particles is improved.

The embodiment also discloses centrifugal dehydration equipment for the water washing treatment of the fly ash pulping, which can be used for the dehydration treatment of the fly ash slurry in the embodiment, and realizes the separation of the fly ash residue and the filtrate of the fly ash slurry; in the process of centrifugally separating the fly ash slurry, the fly ash filter residue in the centrifugal process can be circulated, and the washing treatment can be simultaneously carried out in the centrifugal process by matching with the input washing liquid.

As shown in fig. 3 and 4, the centrifugal dewatering device comprises a barrel 1 and a rotating shaft 2, wherein the barrel 1 is horizontally arranged and is provided with a first end 101 and a second end 102, the direction of the first end 101 can be used for inputting fly ash slurry, the fly ash slurry is dewatered by the centrifugal dewatering device, dewatered filter residues are obtained, the fly ash filter residues can be output from the direction of the second end 102, the centrifugal dewatering of the fly ash is realized, and the fly ash and filtrate can be separated.

The rotating shaft 2 is coaxial with the cylinder body 1 and is supported and fixed through a rack outside; the rotating shaft 2 penetrates through the inner cavity of the cylinder body 1, and is rotatably supported at the two ends of the rotating shaft 2 through the bearing seats 5, so that the rotating shaft 2 can stably and smoothly rotate. And, install the actuating device in the one end position that the pivot 2 stretches out barrel 1, can drive the pivot 2 to rotate.

The rotary seat I4 and the rotary seat II 3 are respectively fixed at the two ends of the rotary shaft 2 penetrating through the cylinder body 1, and the rotary seat I4 and the rotary seat II 3 are fixedly connected with the rotary shaft 2, so that synchronous rotation with the rotary shaft 2 can be realized. The first rotary seat 4 is located at the first end 101 of the cylinder 1, and the bearing seat 5 is located at the second end 102 of the cylinder 1. One side of the rotary seat I4 and one side of the rotary seat II 3 respectively extend into the cylinder body 1, and the two ends of the cylinder body 1 can be closed by keeping a sealed state through a rotary sealing piece at the connecting position. Further, smooth rotation operation can be realized between the first rotary seat 4, the second rotary seat 3 and the cylinder 1.

The outer peripheral position of the rotating shaft 2 is fixedly connected with a first helical blade 6, and the first helical blade 6 is positioned in the inner cavity of the cylinder body 1 and extends spirally along the direction of the rotating shaft 2. The inner cavity of the cylinder body 1 is separated by a first helical blade 6 to form a helical channel. The rotation will drive the material in the cylinder 1 to rotate helically at a high speed during the rotation process, pushing the material helically and pushing the material from the first end 101 towards the second end 102.

Because the specific gravity of the fly ash solid particles is different from that of the liquid, when the fly ash solid particles are subjected to the high-speed rotation action of the first spiral blade 6, the fly ash particles with larger specific gravity are positioned closer to the inner cavity wall of the cylinder 1 under the action of centrifugal force, and the liquid is positioned in the middle position of the cylinder 1. During the spiral pushing, fly ash particles will collect towards the second end 102 of the cartridge 1, whereas the lighter specific gravity water will be closer to the first end 101.

As shown in fig. 5 and 6, a hollow separation chamber 202 is provided at the inner peripheral position of the middle section of the rotating shaft 2; and a plurality of through holes 203 are formed in the peripheral wall of the separation cavity 202, and the plurality of through holes 203 are distributed in an annular array and can be communicated with the inner cavity of the cylinder 1 and the separation cavity 202 in the rotating shaft 2.

As shown in fig. 5 and 7, a water outlet cavity 42 is formed in the rotary seat one 4, and the water outlet cavity 42 is in a ring-shaped structure and is arranged around the rotary shaft 2. The periphery of the rotary seat I4 is provided with water outlet holes 43 communicated with the water outlet cavity 42, and filtrate separated from the barrel 1 by centrifugal filtration can be discharged through the water outlet holes 43, so that fly ash particles and the filtrate are mutually separated.

The rotating shaft 2 is of a hollow structure, an inner hole 201 which is communicated with a separation cavity 202 and a water outlet cavity 42 is formed in the axis of the rotating shaft 2, fly ash particles and filtrate are generated by the material under the centrifugal action of the first helical blade 6, the specific gravity of the filtrate is lighter, and the filtrate is reserved in the middle position inside the barrel body 1. After the filtrate in the middle of the cylinder 1 gathers, the filtrate is discharged from the inner hole 201 in the center of the rotating shaft 2 along with the continuous replenishment of materials, and then enters the water outlet cavity 42. In the outlet chamber 42, the filtrate is again centrifuged and discharged from the peripheral outlet holes 43. Filtrate in the circulation process among the water outlet cavity 42, the inner hole 201 of the rotating shaft 2, the separation cavity 202 and the inner cavity of the cylinder body 1 can be influenced by siphoning, so that the filtrate can be discharged more stably and uniformly.

As shown in fig. 4 and 7, a feeding pipe 7 is installed in the inner hole 201 of the rotating shaft 2, the feeding pipe 7 extends out from the right end of the rotating shaft 2, is connected with a discharge hole of an external fly ash slurry neutralization tank through a rotary joint, and is pumped through a slurry pump, so that the fly ash slurry subjected to neutralization treatment can be fed into the inner hole 201 of the rotating shaft 2 along the feeding pipe 7. The end of the feed pipe 7 forms a feed end 71, and the feed end 71 extends into a separation chamber 202 in the shaft 2 for slurry input.

Slurry is input from the feed pipe 7 and enters the separation cavity 202, and under the action of rotary centrifugation, fly ash particles in the slurry are thrown out from the through holes 203 at the periphery of the separation cavity 202 and enter the cylinder 1; while most of the liquid will be collected in the separation chamber 202. With the continuously input fly ash slurry in the feeding pipe 7, the filtrate accumulated in the separating cavity 202 is pushed into the annular channel formed between the inner hole 201 and the feeding pipe 7, and then flows in the direction of the water outlet cavity 42, so that the filtrate can be separated and discharged.

In order to enhance the separation effect of the fly ash particles in the separation chamber 202, the flow of the fly ash particles from the inner hole 201 to the outlet chamber 42 is reduced. The separation chamber 202 may be tapered toward the bore 201 to form a flare 204 with a smooth transition at the junction. A flare 204 is formed between the separation chamber 202 and the inner bore 201, the flare 204 gradually expanding toward the separation chamber 202. When the particulate matter flows along the filtrate toward the water outlet cavity 42, the particulate matter is continuously centrifuged outward, and the particulate matter is in contact with the inner wall of the inner hole 201 and the separation cavity 202, i.e. the inner peripheral position of the bell mouth one 204. After the particles are propped against the inner peripheral wall of the horn mouth I204, component force which is back to the direction of the water outlet cavity 42 is generated on the particles, and the particles can be pushed towards the direction which is away from the water outlet cavity 42; and along with the movement of the particles towards the water outlet cavity 42, the radius of the first horn mouth 204 is reduced consistently, the component force generated by the centrifugal action on the particles is further increased, the particles are separated from the filtrate in the separation cavity 202, the condition that the particles flow into the water outlet cavity 42 can be reduced, and the smooth and effective separation of the particles and the filtrate is maintained.

As shown in fig. 4 and 5, the first end 101 of the cylinder 1 has a large outer diameter, the second end 102 has a small outer diameter, and a tapered neck 103 is formed between the first end 101 and the second end 102. The shape and size of the rotating shaft 2 inside the cylinder 1 and the shape and size of the first helical blade 6 on the periphery of the rotating shaft 2 are changed adaptively, and the structure shown in fig. 2 and 3 is formed. Because the external diameter of the second end 102 of the barrel 1 is smaller, and the rotation speeds of the rotating shaft 2 at all positions in the barrel 1 are consistent, in the rotation process, the centrifugal effect of the materials in the first end 101 is larger in the rotation process, the greater separation effect on the particles and the filtrate can be achieved, and the filtrate can be separated at the position closer to the first end 101, so that the separation treatment of the fly ash particles and the filtrate is facilitated.

As shown in fig. 5 and 8, one end of the second rotary seat 3 extends into the cylinder 1, and a rotary sealing connector is mounted at the position of the end of the second rotary seat 3 extending into the cylinder 1, so that smoothness of the rotation process and tightness of the second end 102 of the cylinder 1 are maintained, and smooth action of the second rotary seat 3 is maintained.

An annular cavity 32 is formed on the end face of one end, facing the inner cavity of the cylinder body 1, of the second rotating seat 3, and the annular cavity 32 is communicated with the inner cavity of the cylinder body 1 and surrounds the outer peripheral position of the rotating shaft 2 to form an annular structure. A plurality of discharging holes 33 communicated with the annular cavity 32 are formed in the periphery of the second rotating seat 3. In the cylinder 1, the centrifugally separated fly ash particles will collect in the direction of the second end 102 and then enter the annular chamber 32 of the second rotary seat 3. The fly ash filter residues are output from the discharge holes 33 on the periphery of the second rotary seat 3, so that the discharge of fly ash particles is realized.

Further, a return channel 206 may be formed in the rotating shaft 2, and the annular cavity 32 and the separation cavity 202 may be communicated through the return channel 206, so that after centrifugal separation, the fly ash particles entering the annular cavity 32 are returned again through the return channel 206, and then circulate fully. In addition, in the circulating process of the fly ash particles, a washing liquid can be input into the cylinder 1 to wash the fly ash particles. The washing generated in the washing process can be output to the direction of the water outlet cavity 42 after being separated in the separation cavity 202, so that the circulating washing of the fly ash particles is realized, and the centrifugal separation treatment is continued.

Specifically, as shown in fig. 5 and 8, the position of the interior of the rotating shaft 2 corresponding to the separation chamber 202 to the annular chamber 32 is also hollow, and a return passage 206 is formed at the section of the rotating shaft 2. The return channel 206 is arranged coaxially with the rotating shaft 2. At the periphery of the rotating shaft 2, corresponding to the position of the annular cavity 32, a plurality of return holes 207 are formed, and the return holes 207 are communicated with the annular cavity 32 and the return channel 206, so that a return channel can be formed at the position of the material.

To maintain the return efficiency of fly ash material within the return channel 206, a helical blade two 9 may be mounted within the return channel 206. A central shaft 8 is coaxially installed inside the return passage 206, the central shaft 8 is extended from the end of the rotating shaft 2, and a rotary seal is installed at the penetrated position, and a good sealing state is maintained. The left end position of the central shaft 8 extends out of the rotating shaft 2 and is supported by the frame to keep the stable state of the rotating shaft 2, and the rotating shaft 2 does not rotate along with the rotating shaft 2.

A second spiral vane 9 is mounted between the inner periphery of the return passage 206 and the center shaft 8, and the outer periphery of the second spiral vane 9 is fixed to the inner periphery of the return passage 206 and spirally wound around the outer periphery of the center shaft 8 so as to be separated from the center shaft 8. The spiral vane two 9 divides the annular gap between the return channel 206 and the central shaft 8 into spiral channels. In addition, the rotation direction of the second spiral blade 9 is opposite to that of the first spiral blade 6, in the rotation process of the rotating shaft 2, the second spiral blade 9 synchronously rotates along with the rotating shaft 2, and materials are pushed towards the direction of the separation cavity 202 under the action of the spiral blade, so that the materials in the annular cavity 32 can be moved towards the direction of the separation cavity 202, and fly ash residues circulate.

Further, a second flare 205 that is gradually reduced may be formed at a connection position where the separation chamber 202 communicates with the return channel 206, and the second flare 205 is gradually enlarged toward the separation chamber 202. Through the structure of the conical surface of the separation horn mouth two 205, the particles in the separation cavity 202 can gather towards the middle position of the periphery of the separation cavity 202, and then can smoothly flow out from the through hole 203, so that the material separation between the separation cavity 202 and the cylinder body 1 is realized.

Further, the feeding end 71 of the feeding pipe 7 extends to the inner side of the bell mouth two 205, the bell mouth two 205 is located at the left end of the separating chamber 202, and the inner hole 201 is connected to the right side of the separating chamber 202, so that a certain distance is formed between the material and the inner hole 201 after the material is input into the separating chamber 202. The slurry of the materials in the separation chamber 202 is subjected to the converging action of the bell mouth two 205 and the bell mouth one 204, so that the separation effect in the separation chamber 202 can be enhanced, the separation of fly ash particles can be ensured, and the slurry is output from the through holes 203 at the periphery of the separation chamber 202, so that a stable separation action is realized.

Further, a valve assembly 34 can be installed in the annular cavity 32, and the valve assembly 34 can be used for controlling the opening and closing of the discharge hole 33 and the return hole 207 in the rotary seat 4, so that the discharge and the recycling control of the fly ash filter residues can be realized.

As shown in fig. 8 and 9, the valve assembly 34 includes a first annular sleeve 341 and a second annular sleeve 342, and the first annular sleeve 341 and the second annular sleeve 342 are mutually sleeved to form an annular sleeve structure. The first annular sleeve 341 is sleeved on the outer periphery of the rotating shaft 2, the inner periphery of the first annular sleeve 341 is mutually propped against the outer peripheral wall of the rotating shaft 2, and axial sliding adjustment can be realized. A telescopic rod 343 is arranged between the annular sleeve one 341 and the rotary seat one 4, the telescopic rod 343 is provided with a telescopic end which can be actively driven in a telescopic way, and the telescopic end is fixedly connected with the end face of the annular sleeve one 341, so that the annular sleeve one 341 can be axially and reciprocally regulated.

The inner circumference of the first annular sleeve 341 and the outer circumference of the rotating shaft 2 are mutually pressed, the first annular sleeve 341 extends towards the middle section direction of the rotating shaft 2, and a sealing section 345 is formed. The inner circumference of the sealing section 345 abuts against the outer circumference of the rotating shaft 2, and can abut against the outer circumference of the rotating shaft 2, so as to play a role in abutting and sealing the return hole 207 on the rotating shaft 2. The periphery of the sealing section 345 is provided with a material guiding hole 344, when the material guiding hole 344 is opposite to the material returning hole 207, the annular cavity 32 is communicated with the material returning channel 206, so that fly ash particles can enter the material returning channel 206, and the circulating reflux of the fly ash particles can be realized. When the material guiding hole 344 and the material returning hole 207 are offset from each other, the sealing section 345 cuts off the material returning hole 207, and disconnects the annular cavity 32 from the material returning channel 206, so that fly ash particles cannot enter the material returning channel 206 and do not participate in the circulating and returning process.

The second annular sleeve 342 is sleeved on the outer periphery of the first annular sleeve 341, and the outer periphery of the second annular sleeve 342 is opposite to the position of the discharge hole 33. The outer circumferential surface 348 of the second annular sleeve 342 and the inner circumferential wall of the annular cavity 32 are mutually abutted, so that the discharge hole 33 can be closed, the second annular sleeve 342 can be slidably adjusted along the axial direction, and the state stability of the second annular sleeve 342 is maintained.

A first bump 349 is formed at the outer peripheral position of the left end of the first annular sleeve 341, a second bump 3410 is formed at the inner peripheral position of the right end of the annular sleeve, a spring 346 is elastically pressed between the first bump 349 and the second bump 3410, and the second annular sleeve 342 can be elastically supported towards the middle section direction of the rotating shaft 2 under the elastic action of the spring 346. By the elastic supporting function of the spring 346, the axial elastic floating adjustment of the annular sleeve one 341 and the annular sleeve two 342 can be realized, so that the valve assembly 34 can adapt to the adjustment states of the discharge hole 33 and the return hole 207.

Specifically, the return hole 207 is closer to the middle section of the rotating shaft 2 than the discharge hole 33, and the guide hole 344 is located between the discharge hole 33 and the return hole 207, as shown in fig. 9. The first annular sleeve 341 has a retracted position and an extended position.

As shown in fig. 8, the first annular sleeve 341 is in the retracted position, and the material guiding holes 344 and the material returning holes 207 of the first annular sleeve 341 are offset from each other, so that the annular chamber 32 and the material returning channel 206 are cut off, and at this time, the fly ash particles do not circulate. At the same time, the outer circumferential surface 348 of the second annular sleeve 342 presses the discharge hole 33 to be closed, and the position of the discharge hole 33 is relatively closed. Moreover, since the second annular sleeve 342 is elastically adjustable in a direction away from the middle section of the rotating shaft 2, when fly ash particles are continuously gathered in the second end 102 of the cylinder 1 and the annular cavity 32, the fly ash particles will push the second annular sleeve 342 in a leftward direction. The extrusion pushing action of the fly ash pushes the annular sleeve II 342 to move, overcomes the elastic action of the spring 346, and opens the discharge hole 33, so that the fly ash particles subjected to centrifugal separation can be output, and the dehydration of the fly ash slurry is realized.

In addition, due to the elastic action of the spring 346, a certain pressure can be formed near the first end 101 of the annular cylinder 1, and the output of the fly ash particles can be realized only after the fly ash particles reach a certain pressure; further, the separation treatment of the particulate matter and the filtrate is facilitated.

As shown in fig. 9, the first ring 341 is in an extended position, and the second ring 342 is moved toward the middle of the shaft 2, i.e., toward the right as viewed in the drawing, by pushing the telescopic rod 343, so that the valve assembly 34 is adjusted from the retracted position to the extended position. At this time, the material guiding hole 344 on the sealing section 345 of the first annular sleeve 341 is opposite to the material returning hole 207, and the valve assembly 34 opens the material discharging hole 33 to communicate the annular cavity 32 with the material returning channel 206, so that the fly ash particles can circulate through the material returning channel 206, and further the circulating treatment of the fly ash particles can be realized.

At this time, the second annular sleeve 342 moves synchronously with the first annular sleeve 341, the second annular sleeve 342 moves to the right position, the outer circumferential surface 348 of the second annular sleeve 342 presses the discharge hole 33 to be closed, and the second annular sleeve 342 is located at the right position of the discharge hole 33, so that the inner cavity of the cylinder 1 can be separated from the discharge hole 33, and the fly ash particles in the cylinder 1 are prevented from being output outwards. Meanwhile, in the elastic adjustment process, the annular sleeve two 342 is limited by the first stop block and the second stop block, so that the separation state of the discharge hole 33 and the cylinder 1 can be always kept, and the discharge closing state is kept.

Through the continuous circulation, the fly ash particles in the middle can be continuously and repeatedly circulated, and in the circulation process, washing liquid can be introduced into the cylinder body 1 to circularly wash the fly ash particles, so that the finally output fly ash particles can be cleaner.

During the circulation process, the feeding pipe 7 is suspended to feed fly ash slurry, and washing liquid can be introduced, so that the washing liquid is used for carrying out circulation washing treatment on the fly ash particles, and the cleanliness of the fly ash particles is improved.

Alternatively, the center shaft 8 may be hollow, and the washing liquid may be introduced into the separation chamber 202 through the center shaft 8, so that the fly ash particles may be washed. Further, holes may be formed at the position of the central shaft 8 corresponding to the return channel 206, so that the input washing liquid can be input into the return channel 206, and the fly ash particles can be uniformly mixed with the washing liquid, so as to play a role in uniformly and effectively washing the fly ash particles.

The present embodiment discloses a process for washing fly ash with water, which uses the above-mentioned apparatus for washing fly ash with water and centrifugal dewatering apparatus for washing fly ash, and will be described in detail with reference to fig. 1 and 2.

The fly ash pulping water washing process comprises the following steps: pulping, pH neutralization, centrifugal dehydration and water washing treatment, most pollutants in raw material fly ash can be eliminated by water washing, and relatively clean fly ash is obtained, so that secondary pollution generated in the subsequent recycling process of the fly ash can be greatly reduced.

Pulping: raw material fly ash and water are put into a pulping tank, and the fly ash and the water are mixed by stirring to form fly ash slurry; and the fly ash slurry is continuously stirred, so that the conditions of slurry separation and bottoming are avoided.

pH neutralization: introducing the fly ash slurry into a pH neutralizing tank, and detecting the pH value of the fly ash slurry through pH detection equipment; adding 30% hydrochloric acid into the neutralization pond according to the pH value of the fly ash slurry, and neutralizing the pH value of the fly ash slurry; in general, the pH value of the fly ash slurry needs to be adjusted to be slightly acidic, and the specific value can be adjusted according to different requirements; through the effect of hydrochloric acid, the calcium in the fly ash is dissolved into water, and then the filtrate in the regulating tank is recycled, so that byproducts can be obtained through recycling, and heavy metals in the fly ash can enter the filtrate to be separated from fly ash particles in an acidic environment.

And (3) centrifugal dehydration: the pH-neutralized and regulated fly ash slurry is subjected to centrifugal dehydration treatment, and the water in the fly ash and fly ash particles can be mutually separated through high-speed centrifugal rotation, so that filtrate and fly ash filter residues are obtained; most of the contaminants in the fly ash will follow the filtrate into the conditioning tank, separating the contaminants from the fly ash particles.

The centrifugal dehydration process adopts the centrifugal dehydration equipment in the embodiment to carry out centrifugal treatment, so that separation can be realized, and meanwhile, supplementary water washing is carried out, and the washing liquid input in the water washing process can adopt filtrate in the subsequent water washing process. The concentration of the filtrate in the subsequent water washing process is lower than that of the filtrate in the current centrifugal treatment process, so that the concentration of pollutants in the fly ash filter residues can be properly reduced by supplementing water washing. Or, the washing liquid can be continuously introduced into the process of centrifugal dehydration to carry out continuous circulation washing, so that the cleanliness of the fly ash obtained after centrifugal dehydration can be greatly reduced, the cleanliness of the fly ash can meet the requirement after the circulation is continued for a certain time, and the subsequent washing treatment step can be also canceled.

And (3) water washing treatment: putting the fly ash filter residue obtained by centrifugal dehydration into a washing stirring tank, adding water, mixing and stirring the fly ash again through stirring to form fly ash slurry, and diluting the filtrate residue in the original fly ash slurry; and then, separating and treating the fly ash slurry through centrifugal dehydration equipment to obtain fly ash filter residues and filtrate, so that the residue in the fly ash filter residues can be reduced.

In the water washing treatment process, repeated stirring and centrifugal dehydration filtration treatment can be carried out for a plurality of times, so that the residue in the fly ash filter residue can be further reduced; in general, three-stage water washing filtration can be adopted, namely, the filter residue after centrifugal dehydration is subjected to three times of water washing and three times of dehydration, and the washing liquid in the last washing process only adopts clear water; in the previous two washing processes, the filtrate of the next washing process can be adopted, so that the washing effect can be achieved, and the water consumption can be reduced.

The content of pollutants in the fly ash can be effectively reduced by repeatedly washing the fly ash for a plurality of times, so that cleaner and pollution-free fly ash is obtained, secondary pollution of the fly ash in the subsequent utilization process is reduced, and the reuse of the fly ash is facilitated.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above examples, and all technical solutions belonging to the concept of the present invention belong to the protection scope of the present invention. It should be noted that modifications and adaptations to the present invention may occur to one skilled in the art without departing from the principles of the present invention and are intended to be within the scope of the present invention.

Claims

1. The fly ash pulping water washing equipment comprises a raw ash bin, a pulping tank, a neutralization tank, centrifugal dehydration equipment, a water washing ash bin and an adjusting tank, and is characterized in that the centrifugal dehydration equipment comprises a barrel (1) and a rotating shaft (2), wherein the barrel (1) is horizontally arranged, and the rotating shaft (2) and the barrel (1) are coaxially arranged and penetrate through two ends of the barrel (1); the rotary seat I (4) and the rotary seat II (3) are respectively fixed at the positions of the periphery of the rotary shaft (2) corresponding to the two ends of the cylinder body (1), and the rotary seat I (4) and the rotary seat II (3) are rotationally connected with the cylinder body (1) and keep the cylinder body (1) sealed; the periphery of the rotating shaft (2) is provided with a first helical blade (6) corresponding to the position in the cylinder body (1), and the first helical blade (6) is used for helically pushing materials when the rotating shaft (2) rotates; the inner periphery of the middle section of the rotating shaft (2) is provided with a hollow separation cavity (202), and the outer periphery of the separation cavity (202) is provided with a through hole (203) communicated with the inner cavity of the cylinder body (1); the inside of the rotary seat I (4) is provided with a water outlet cavity (42), the rotary seat I (4) is provided with a water outlet hole (43) communicated with the water outlet cavity (42), and the axis of the rotary shaft (2) is provided with an inner hole (201) communicated with the separation cavity (202) and the water outlet cavity (42); a feeding pipe (7) is arranged in the inner hole (201), the feeding pipe (7) extends out from one end of the rotating shaft (2), and the other end is a feeding end (71) and extends into the separation cavity (202);

one end of the second rotating seat (3) stretches into the cylinder body (1), an annular cavity (32) is formed in one end of the second rotating seat (3) stretching into the cylinder body (1), the annular cavity (32) is communicated with the inner cavity of the cylinder body (1), and a discharging hole (33) communicated with the annular cavity (32) is formed in the periphery of the second rotating seat (3);

the rotary shaft (2) is hollow at a position corresponding to the separation cavity (202) to the annular cavity (32) and is provided with a return channel (206), and a return hole (207) for communicating the annular cavity (32) with the return channel (206) is formed at a position corresponding to the annular cavity (32) in the rotary shaft (2);

a valve assembly (34) is arranged in the annular cavity (32), the valve assembly (34) comprises a first annular sleeve (341) and a second annular sleeve (342), and the first annular sleeve (341) is sleeved on the periphery of the rotating shaft (2) and is driven to axially and reciprocally adjust through a telescopic rod (343); the second annular sleeve (342) is sleeved on the periphery of the first annular sleeve (341), and the periphery of the second annular sleeve (342) is opposite to the position of the discharge hole (33) and is used for opening and closing the discharge hole (33); a spring (346) is elastically pressed between the first annular sleeve (341) and the second annular sleeve (342), and the spring (346) is used for elastically supporting the second annular sleeve (342) towards the middle section direction of the rotating shaft (2).

2. A fly ash pulping water washing apparatus according to claim 1, characterized in that the return channel (206) is provided with a coaxially arranged central shaft (8), which central shaft (8) extends from the end of the shaft (2) and through the return channel (206); the central shaft (8) is kept fixed by an external bracket; a second helical blade (9) is arranged between the inner periphery of the return channel (206) and the central shaft (8), the outer periphery of the second helical blade (9) is fixed with the inner peripheral wall of the return channel (206) and separated from the central shaft (8), and the rotation directions of the second helical blade (9) and the first helical blade (6) are opposite and are used for pushing materials towards the separating cavity (202).

3. A fly ash pulping water washing apparatus according to claim 1, characterized in that the separation chamber (202) communicates with the inner bore (201) and tapers in the direction of the inner bore (201); a horn mouth I (204) is formed between the separation cavity (202) and the inner hole (201), and the horn mouth I (204) gradually expands towards the direction of the separation cavity (202).

4. A fly ash pulping water washing apparatus according to claim 1, characterized in that the separation chamber (202) communicates with the return channel (206) and tapers in the direction of the return channel (206); a horn mouth II (205) is formed between the separation cavity (202) and the return channel (206), and the horn mouth II (205) gradually expands towards the direction of the separation cavity (202); the feeding end (71) of the feeding pipe (7) extends to the inner side of the bell mouth II (205).

5. A fly ash pulping and washing device according to claim 1, characterized in that the inner circumference of the annular sleeve (341) is pressed against the outer circumference of the rotating shaft (2), the annular sleeve (341) extends towards the middle section of the rotating shaft (2) and forms a sealing section (345); the inner periphery of the sealing section (345) is propped against the outer periphery of the rotating shaft (2) and is used for propping and sealing the feed back hole (207); a material guiding hole (344) is formed in the periphery of the sealing section (345), and when the material guiding hole (344) is opposite to the material returning hole (207), the annular cavity (32) is communicated with the material returning hole (207); when the material guiding hole (344) and the material returning hole (207) are staggered, the sealing section (345) cuts off the material returning hole (207) and cuts off the annular cavity (32) and the material returning channel (206).

6. A fly ash pulping water washing apparatus according to claim 5, characterized in that the return hole (207) is closer to the middle section of the shaft (2) than the discharge hole (33); the first annular sleeve (341) has a contracted position and an extended position; the first annular sleeve (341) is positioned at the contraction position, a material guide hole (344) and a material return hole (207) of the first annular sleeve (341) are staggered, the outer peripheral surface (348) of the second annular sleeve (342) is used for propping and closing the material outlet (33), the second annular sleeve (342) can be elastically adjusted towards the direction deviating from the middle section of the rotating shaft (2), and the material outlet (33) can be opened; the annular sleeve I (341) is positioned at the extending position, and the annular sleeve II (342) moves towards the middle section direction of the rotating shaft (2); the material guiding hole (344) is opposite to the material returning hole (207), the outer peripheral surface (348) of the annular sleeve II (342) presses and seals the material discharging hole (33), and the annular sleeve II (342) always keeps the material discharging hole (33) separated from the cylinder body (1) in the elastic adjustment process.

7. A process for washing fly ash pulping, which is characterized in that the fly ash pulping washing equipment as claimed in any one of claims 1 to 6 is adopted for treatment; the method comprises the following steps: