阅读说明：本技术 一种渣浆处理方法 (Slag slurry treatment method ) 是由 马军 胡开达 霍福科 何瑞 法迁 刘健超 于 2021-10-19 设计创作，主要内容包括：本发明的渣浆处理方法,包括以下步骤：用预分离设备分离渣浆,以形成有第一含固物料和第一液态物料；用沉降设备二次分离第一液态物料,以形成有第二含固物料和第二液态物料；用浓缩提纯设备浓缩并提纯第二液态物料,以形成有第三含固物料和氯硅烷；用浓渣收集设备收集第一含固物料、第二含固物料及第三含固物料,以形成有第四含固物料。本发明工作时能够对渣浆进行二次分离,以此提高对渣浆分离的效率,且具有减少渣浆的损耗,进而具有降低渣浆处理成本的作用。(The slag slurry treatment method comprises the following steps: separating the slurry with a pre-separation device to form a first solid-containing material and a first liquid material; secondarily separating the first liquid material by using a settling device to form a second solid-containing material and a second liquid material; concentrating and purifying the second liquid material by using a concentration and purification device to form a third solid-containing material and chlorosilane; and collecting the first solid-containing material, the second solid-containing material and the third solid-containing material by using concentrated slag collecting equipment to form a fourth solid-containing material. The slag-slurry separation device can perform secondary separation on slag slurry during working, so that the slag-slurry separation efficiency is improved, the loss of the slag slurry is reduced, and the slag-slurry treatment cost is further reduced.)

1. The method for treating the slag slurry is characterized by comprising the following steps of:

separating the slurry with a pre-separation device (10) to form a first solids-containing material and a first liquid material;

secondarily separating the first liquid material with a settling device (20) to form a second solid-containing material and a second liquid material;

concentrating and purifying the second liquid stream with a concentration and purification unit (30) to form a third solids-containing stream and chlorosilane;

the first solid-containing material, the second solid-containing material and the third solid-containing material are collected by a concentrated slag collecting device (40) to form a fourth solid-containing material.

2. The slurry processing method according to claim 1, further comprising:

neutralizing the fourth solids content with a neutralization apparatus (50) to form a slurry.

3. The slag slurry treatment method according to claim 1, wherein a heating device is arranged on the concentrated slag collecting device (40), and the heating device can heat a fourth solid-containing material in the concentrated slag collecting device (40) so as to control the temperature of the fourth solid-containing material to be 60-150 ℃ and generate a gaseous mixture when the pressure is 0.05-0.3 MPa; and the concentration and purification equipment (30) can receive the gaseous mixture and perform concentration and purification on the gaseous mixture.

4. The slag slurry treatment method according to claim 3, wherein a stirring device is further arranged on the concentrated slag collecting device (40), and the stirring device is used for stirring the fourth solid-containing material in the concentrated slag collecting device (40).

5. The method for treating sludge slurry according to claim 1, wherein the pre-separation device (10) is provided as a cyclone separator, and the sludge slurry introduced into the cyclone separator can be separated into a first solid-containing material and a first liquid material under the action of centrifugal force, wherein the outer diameter of the first solid-containing material is 150-300 μm.

6. The slag slurry treatment method according to claim 5, wherein the cyclone separator comprises a conical cylinder (11), the conical cylinder (11) is connected and communicated with an inlet pipe (12), and the inlet pipe (12) can guide the slag slurry into the conical cylinder (11) in a tangential manner.

7. The slag slurry treatment method according to claim 6, wherein an outlet pipe (13) is arranged on the conical cylinder (11) along the direction of the circle center line of the conical cylinder (11), the outlet pipe (13) can pass through the area where the inlet pipe (12) is arranged and extend into the conical cylinder (11), and the first liquid material can be discharged outwards through the outlet pipe (13); and a powder outlet (14) is formed in one end, far away from the outlet pipe (13), of the conical cylinder body (11), and the first solid-containing material can be discharged outwards through the powder outlet (14).

8. The slag slurry treatment process according to claim 1, characterized in that the settling device (20) is provided as a settling tank.

9. The slag slurry treatment method according to claim 1, wherein the concentration and purification equipment (30) is configured as a purification tower, and wherein the overhead pressure of the purification tower is 0.05MPa to 0.25 MPa.

10. The slag slurry treatment method according to claim 1, characterized in that the concentrated slag collection device (40) is provided as a concentrated slag collection tank.

Technical Field

The invention belongs to the technical field related to polycrystalline silicon production, and particularly relates to a slag slurry treatment method.

Background

The production process of the polycrystalline silicon inevitably generates slag slurry, wherein the slag slurry is chlorosilane slag slurry which mainly contains solid particles such as silicon powder, Cu, Fe and AL and liquid materials such as silicon tetrachloride, trichlorosilane, high-boiling-point substances, metal chlorides and the like. Wherein, the content of solid substances in the chlorosilane slurry is between 0.5 and 30 percent, and the proportion of silicon tetrachloride in liquid substances reaches more than 90 percent.

At present, the following three methods are mainly used for treating the slurry generated in the production process of polycrystalline silicon: the first is direct heating flash evaporation, after a small amount of silicon tetrachloride in the slag slurry is recovered by flash evaporation, the waste slag is directly hydrolyzed and delivered. The second method is to adopt a method of adding a dryer for sedimentation, firstly, the slag slurry is separated by sedimentation, the waste slag is further dried in the dryer and then is hydrolyzed, and clear liquid is recovered by a tower. And thirdly, adopting vacuum drum filtration, filtering chlorosilane in the slurry through a vacuum drum, discharging the hydrolyzed filter residue, and directly recovering clear liquid.

However, the method of directly heating and flashing the slurry has the disadvantages of low material recovery rate and large amount of waste water. The method of settling and adding a dryer can treat the slurry to a certain degree, but the settling time of the settling tank is longer and the treatment efficiency is low. The vacuum drum method is affected by the filter aid medium, so that the treatment capacity and the treatment efficiency are not high. Therefore, the invention provides a novel system for treating the slurry.

Therefore, it is necessary to provide a new slurry treatment method for treating chlorosilane slurry generated in the polysilicon production process.

Disclosure of Invention

Based on this, it is necessary to provide a method for treating slurry in order to solve the technical problems in the prior art.

A method for treating slurry comprises the following steps:

separating the slurry with a pre-separation device to form a first solid-containing material and a first liquid material;

secondarily separating the first liquid material by using a settling device to form a second solid-containing material and a second liquid material;

concentrating and purifying the second liquid material by using a concentration and purification device to form a third solid-containing material and chlorosilane;

and collecting the first solid-containing material, the second solid-containing material and the third solid-containing material by using concentrated slag collecting equipment to form a fourth solid-containing material.

In the application, the treatment of the slurry is specifically realized through the arrangement of the steps, the slurry can be pre-separated by using pre-separation equipment and then separated by using sedimentation equipment, so that the secondary separation of the slurry is realized, and the effect of improving the separation efficiency of the slurry when the slurry treatment method works is realized; and the first solid-containing material, the second solid-containing material and the third solid-containing material are collected by the concentrated slag collecting equipment, so that high-concentration slag discharge during the operation of the slag slurry treatment method is realized, the loss of slag slurry is reduced, and the slag slurry treatment cost is further reduced.

In one embodiment, the method further comprises the following steps:

neutralizing the fourth solids content with a neutralization apparatus to form a slurry.

It can be understood that the fourth solid material of the concentrated slag collecting device can be neutralized by the neutralizing device when the slag slurry processing method works through the arrangement of the steps, so that the purpose of processing the fourth solid material is achieved.

In one embodiment, the concentrated slag collecting device is provided with a heating device, and the heating device can heat a fourth solid-containing material in the concentrated slag collecting device so as to control the temperature of the fourth solid-containing material to be 60-150 ℃ and generate a gaseous mixture when the pressure is 0.05-0.3 MPa; and the concentration and purification equipment can receive the gaseous mixture and perform concentration and purification on the gaseous mixture.

It can be understood that through the structural arrangement of the heating device, in the process of collecting solid-containing materials in the slag slurry, the concentrated slag collecting device can discharge liquid materials doped in the solid-containing materials to the concentration and purification device in a heating and evaporation mode, so that the concentrated slag collecting device has the effect of further improving the concentration of the solid-containing materials collected by the concentrated slag collecting device, further reducing the loss of the slag slurry and reducing the effect of neutralizing wastewater generated in the neutralizing process of the neutralizing device.

In one embodiment, a stirring device is further arranged on the concentrated slag collecting device, and the stirring device is used for stirring the fourth solid-containing material in the concentrated slag collecting device.

It can be understood that, through the structure of the stirring device, the liquid material can be separated from the solid-containing material under the heating of the heating device, and further, the liquid material in the concentrated slag collecting device can be discharged to the concentrating and purifying device conveniently.

In one embodiment, the pre-separation device is provided as a cyclone separator, and the slurry led into the cyclone separator can be separated into a first solid-containing material and a first liquid material under the action of centrifugal force, wherein the outer diameter of the first solid-containing material is 150-300 μm.

It can be understood that, through the above structure arrangement, the structure arrangement of the pre-separation device is specifically realized, so that when the pre-separation device works, the separation of solid materials and liquid materials contained in the slag slurry can be realized by utilizing the interaction of centrifugal force, gravity and inertia force, and the separation efficiency is high.

In one embodiment, the cyclone separator comprises a conical cylinder body, an inlet pipe is connected to the conical cylinder body and communicated with the conical cylinder body, and the inlet pipe can guide slag slurry into the conical cylinder body in a tangential mode.

It can be understood that through the structural arrangement, when the slurry is introduced into the cyclone separator, the slurry can generate corresponding centrifugal force, so that the structure is simplified, and the cyclone separator can conveniently generate and prepare.

In one embodiment, an outlet pipe is inserted into the conical cylinder along the direction of the circle center line of the conical cylinder, the outlet pipe can pass through the area where the inlet pipe is located and extend into the conical cylinder, and the first liquid material can be discharged outwards through the outlet pipe; and a powder outlet is formed in one end, far away from the outlet pipe, of the conical barrel, and the first solid-containing material can be discharged outwards through the powder outlet.

It can be understood that through the structural arrangement, when the cyclone separator works, the liquid material can be discharged outwards from the outlet pipe of the conical cylinder, and the solid-containing material is discharged outwards from the powder outlet of the conical cylinder, so that the solid-containing material and the liquid material in the slurry are separated from each other when passing through the cyclone separator.

In one embodiment, the settling device is configured as a settling tank.

It can be understood that, through the above structure arrangement, the structure arrangement of the sedimentation equipment is specifically realized, and the sedimentation tank can be made of local materials, so that the sedimentation equipment has the effect of reducing the production cost of the sedimentation equipment.

In one embodiment, the concentration and purification equipment is set as a purification tower, wherein the overhead pressure of the purification tower is 0.05 MPa-0.25 MPa.

It can be understood that, through the above structure arrangement, the structure arrangement of the concentration and purification equipment is realized, and the purification tower can be made of local materials, so that the production cost of the concentration and purification equipment is reduced.

In one embodiment, the slag collection apparatus is configured as a slag collection tank.

It can be understood that through the structural arrangement, the structural arrangement of the concentrated slag collecting device is specifically realized, the concentrated slag collecting tank can be made of local materials, and the effect of reducing the production cost of the concentrated slag collecting device is achieved.

Drawings

Fig. 1 is a process flow diagram of a slurry treatment method according to an embodiment of the present disclosure.

FIG. 2 is a schematic structural diagram of a preseparation apparatus according to the present application.

Fig. 3 is a schematic structural diagram of a slurry processing system according to the present application.

10, pre-separation equipment; 11. a conical cylinder; 12. an inlet tube; 13. an outlet pipe; 14. a powder outlet; 20. settling equipment; 30. concentration and purification equipment; 40. a dense slag collection device; 50. and (4) neutralizing equipment.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Referring to fig. 1 to 3, a method for processing slurry according to an embodiment of the present invention includes the following steps:

separating the slurry with a preseparation device 10 to form a first solids-containing material and a first liquid material;

secondarily separating the first liquid material with the settling device 20 to form a second solid-containing material and a second liquid material;

concentrating and purifying the second liquid feed with a concentration and purification unit 30 to form a third solids-containing material and chlorosilane;

the first solid-containing material, the second solid-containing material, and the third solid-containing material are collected with the thick slag collecting device 40 to form a fourth solid-containing material.

Further, the slag slurry treatment method further comprises the following steps: the fourth solids content is neutralized with a neutralization apparatus 50 to form a slurry.

It can be understood that the slurry treatment system corresponding to the slurry treatment method of the embodiment includes a pre-separation device 10, a settling device 20, a concentration and purification device 30, a concentrated slag collection device 40 and a neutralization device 50.

The pre-separation device 10 of the present embodiment is used for receiving the slurry and performing a primary separation on the slurry to generate a first solid-containing material and a first liquid material; the settling device 20 is adapted to receive the first liquid material and to secondarily separate it to produce a second solids containing material and a second liquid material; the concentration and purification equipment 30 is used for receiving the second liquid material and concentrating and purifying the second liquid material to generate a third solid-containing material and chlorosilane; the concentrated slag collecting device 40 is used for receiving the first solid-containing material, the second solid-containing material and the third solid-containing material to form a fourth solid-containing material; the neutralization apparatus 50 is adapted to receive the fourth solids containing material and to effect a neutralization reaction thereon to produce a slurry. It should be noted that the slurry generated after the neutralization by the neutralization device 50 may be directly sent out.

It is understood that the first solid material, the second solid material and the third solid material are inevitably mixed with liquid material, and the liquid material contained in each solid material has different compositions. Similarly, the first liquid material and the second liquid material are inevitably doped with solid-containing materials, and the components of the liquid materials contained in each liquid material are different from each other. It should be noted that the solid-containing material specifically refers to a mixture of a liquid phase and a solid in the slurry, and the specific gravity of the solid in the first solid-containing material, the second solid-containing material and the third solid-containing material gradually increases, and the liquid material specifically refers to a mixture of liquid materials in the slurry, which will not be described herein.

From the above, when the slurry treatment method works, the slurry can be separated for the second time, so that the efficiency of separating the slurry when the slurry treatment method works is improved; and the first solid-containing material, the second solid-containing material and the third solid-containing material are collected by the concentrated slag collecting device 40, so that high-concentration slag discharge during the operation of the slag slurry treatment method is realized, the loss of the slag slurry is reduced, the effect of neutralizing waste water generated in the neutralizing process of the neutralizing device is reduced, and the effect of reducing the slag slurry treatment cost is further realized.

In this embodiment, the concentrated slag collecting device 40 of this embodiment is provided with a heating device (not shown), and the heating device can heat the fourth solid-containing material in the concentrated slag collecting device 40 to generate a gaseous mixture; and the concentration and purification equipment 30 can receive the gaseous mixture and perform concentration and purification on the gaseous mixture. In the process of collecting solid materials in the slag slurry, the concentrated slag collecting device 40 can discharge liquid materials doped in the solid materials to the concentration and purification device 30 in a heating and evaporation mode, so that the concentrated slag collecting device 40 has the effect of further improving the concentration of the solid materials collected by the concentrated slag collecting device 40, further reducing the loss of the slag slurry and reducing the effect of neutralizing wastewater generated in the neutralizing process of the neutralizing device 50. It should be noted that in the slag slurry processing method of this embodiment, the concentrated slag collecting device 40 specifically uses steam to heat the fourth solid-containing material, and when the concentrated slag collecting device 40 works, the temperature of the fourth solid-containing material is specifically controlled to be 60 ℃ to 150 ℃, and the pressure is controlled to be 0.05MPa to 0.3 MPa.

Further, the thick slag collecting device 40 of the present embodiment is further provided with a stirring device (not shown), and the stirring device is used for stirring the fourth solid-containing material in the thick slag collecting device 40. So that the heating device heats the fourth solid material in the concentrated slag collecting device 40, and the stirring device plays a role of stirring the fourth solid material, so that the liquid material is separated from the solid material under the heating of the heating device, and further the liquid material in the concentrated slag collecting device 40 is discharged to the concentration and purification device 30.

Specifically, the thick slag collecting device 40 of the present embodiment is provided as a thick slag collecting tank. The structure of the concentrated slag collecting device 40 is specifically realized, the concentrated slag collecting tank can be made of local materials, and the effect of reducing the production cost of the concentrated slag collecting device 40 is achieved.

In this embodiment, the preseparation device 10 of this embodiment is configured as a cyclone, and the slurry introduced into the cyclone can be separated into the first solid-containing material and the first liquid material under the action of centrifugal force. The structural arrangement of the pre-separation equipment 10 is specifically realized, so that when the pre-separation equipment 10 works, the separation of solid materials and liquid materials contained in slurry can be realized by utilizing the interaction of centrifugal force, gravity and inertia force, and the separation efficiency is high.

Specifically, the cyclone separator of the embodiment comprises a conical cylinder 11, an inlet pipe 12 is connected and communicated with the conical cylinder 11, and the inlet pipe 12 can guide the slurry into the conical cylinder 11 in a tangential manner. When the slag slurry is guided into the cyclone separator, the slag slurry can generate corresponding centrifugal force, and the cyclone separator has the advantages of simplified structure and convenience in production and preparation. It should be noted that, the slurry is introduced into the conical cylinder 11 in a tangential manner, specifically, the slurry can be introduced into the conical cylinder 11 in a tangential direction of a circular wall of a portion of the conical cylinder 11 connected with the inlet pipe 12, so that the slurry introduced into the conical cylinder moves along an inner wall of the conical cylinder under the action of centrifugal force, and the description is not provided herein.

An outlet pipe 13 is inserted into the conical cylinder 11 along the direction of the circle center line of the conical cylinder, the outlet pipe 13 can pass through the area where the inlet pipe 12 is located and extend into the conical cylinder 11, and the first liquid material can be discharged outwards through the outlet pipe 13; and a powder outlet 14 is formed in one end, far away from the outlet pipe 13, of the conical cylinder body 11, and the first solid-containing material can be discharged outwards through the powder outlet 14. When the cyclone separator works, liquid materials can be discharged outwards from the outlet pipe 13 of the conical cylinder body 11, solid materials are discharged outwards from the powder outlet 14 of the conical cylinder body 11, and the solid materials and the liquid materials in the slag slurry are separated when passing through the cyclone separator. It should be noted that in the slurry treatment method of the present embodiment, after the slurry is separated by the pre-separation device 10, the solid particles with a particle size of more than 150 μm to 300 μm can be pre-separated.

In this embodiment, the settling device 20 of this embodiment is configured as a settling tank, so as to specifically realize the structural configuration of the settling device 20, and the settling tank can be made of local materials, and has an effect of reducing the production cost of the settling device 20. In the slurry treatment method of the present embodiment, the solid particles having a particle size of less than 150 μm to 300 μm can be settled by the settling in the settling device 20.

The concentration and purification equipment 30 of the embodiment is configured as a purification tower, so that the structure of the concentration and purification equipment is specifically realized, the purification tower can be made of local materials, and the production cost of the concentration and purification equipment 30 is reduced.

The concentration and purification apparatus 30 of the present embodiment may be a plate column or a packed column, and is preferably a plate column. It should be noted that, in the slurry treatment method of the present embodiment, the concentration and purification device 30 specifically adopts a rectification tower to concentrate and purify the second liquid material, and the pressure at the top of the rectification tower is between 0.05 and 0.25MPa when the rectification tower works.

In the present embodiment, the neutralization device 50 of the present embodiment is provided as a neutralization tank. The structural arrangement of the neutralization equipment 50 is realized, and the neutralization tank can be made of local materials, so that the production cost of the neutralization equipment 50 is reduced.

It should be noted that the neutralization material used in the neutralization tank of this embodiment is water, alkali or lime milk, and silicic acid, calcium silicate and silica are generated after the neutralization reaction of the solid-containing material of the slurry and the neutralization material, that is, the slurry is a mixture of the silicic acid, calcium silicate and silica, which will not be described herein.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express a few embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.