CN103977956A - Device and method for separating harmful elements such as alkali and zinc elements in dry dedusting ash of blast furnace - Google Patents

Abstract

The invention relates to a device and a method for separating harmful elements such as alkali and zinc in blast furnace dry dust removal dust. The device includes: dust removal ash bin, conveying pipeline, dust separator, fine dust conveying pipe and bag collection bin; the top of the dust removal ash bin communicates with the bottom of the dust separator; the upper end of the dust separator is collected by the fine dust conveying pipe and the bag The warehouse is connected; the conveying pipeline is connected with the dust separator. The method comprises: spraying the dedusting dust into the dust separator through the conveying pipeline by using a bin pump; the large particle dust falls into the dust removal bin under the action of gravity; and the small particle dust is introduced into the bag collection bin along with the airflow. The device and method effectively reduce the enrichment phenomenon of alkali and zinc elements in the process of reusing blast furnace dry dedusting ash, and realize the recyclable and green concept of blast furnace ironmaking process.

Description

A device and method for separating harmful elements such as alkali and zinc in blast furnace dry dust removal ash

technical field

The invention relates to the technical field of solid waste resource treatment methods such as blast furnace dedusting ash, and in particular to a device and method for separating harmful elements such as alkali and zinc in blast furnace dry dedusting ash.

Background technique

Harmful elements such as alkali and zinc in the raw fuel of the blast furnace are reduced in the high-temperature area of the middle and upper parts of the blast furnace body, and then oxidized again when the gas flow rises to a lower temperature area, and adhere to the falling charge to enter the high temperature again. In the blast furnace area, the phenomenon of enrichment of harmful elements such as alkali and zinc in the blast furnace has been formed repeatedly, which has a certain impact on the normal production of the blast furnace; some of the harmful elements such as alkali and zinc are attached to the fine dust in the rising gas. After being taken out of the furnace, it enters the bag filter after passing through the gravity and cyclone dust collector, and is recovered by the bag. Usually, this part of dust removal ash contains about 35-40% iron element, and also enriches about 3-10% zinc oxide and higher content of potassium, sodium, lead, arsenic and other harmful elements, which is much higher than that of gravity dust removal. ash and cyclone dust. The direct use of these dedusting ash for sintering will lead to serious enrichment of harmful elements such as alkali and zinc in the blast furnace, especially the high enrichment of zinc, which directly affects the smooth operation and longevity of the blast furnace; Dust removal ash cannot be used due to its high zinc oxide content, so it has to be taken out, discarded, or buried deeply, which has caused serious pollution to the environment.

The existing blast furnace dry dust dezincification methods mainly include high temperature method, chemical method, physical method, hydrocyclone method and so on. The high-temperature method is aimed at the final and complete removal of zinc. Although more than a dozen production lines such as rotary hearth furnaces have been built in China, due to the large project investment and high operating costs, it is not suitable for the current situation of low zinc content in blast furnace dry dust removal.

The chemical method was eliminated due to the problems of acid wastewater treatment and equipment corrosion.

The physical method is mainly a magnetic separation process, which is divided into dry method and wet method. The dry method is mainly based on the paramagnetism difference between the high zinc content part and the low zinc content part in the blast furnace dust removal dust, and plays a role in reducing the zinc content in the dust removal dust. The wet method generally uses acid, alkali or ammonia salt solution to extract and separate zinc, lead and other substances to obtain high-quality zinc and lead products. Due to the overall low leaching rate of the wet method, only less than 40% of the zinc in the dust removal dust of the blast furnace can be recovered, and the productivity is not high; in addition, the operating environment of the dry method and the wet method are harsh, causing secondary pollution to the environment, and are not suitable for industrial applications.

The hydrocyclone method needs to prepare a slurry with a certain concentration of dedusting ash and water, and use a hydrocyclone to separate the part with a higher zinc content in the top flow and the part with a lower zinc content in the bottom flow, and then dehydrate through a filter press to form a mud cake. After drying Perform terminal dezincification. The hydrocyclone method is suitable for the treatment of blast furnace wet dust removal, but the treatment equipment is complicated, the process parameters are not easy to control, and the cement cake is inconvenient for subsequent processes.

Contents of the invention

In order to solve the above problems, the present invention provides a method that can effectively separate the large particle dust and small particle dust in the dust removal ash, and can make 80% of the dust removal dust by collecting and recycling the separated large particle dust and small particle dust. Zinc oxide and a certain amount of harmful elements are recycled, and the zinc oxide content in the remaining dust can be controlled below 2.0%. The device and method can be used for the harmless utilization of the sintering process to separate the harmful elements such as alkali zinc in the blast furnace dry dust removal ash.

A device for separating harmful elements such as alkali and zinc in blast furnace dry dust removal ash provided by the invention comprises:

Dust removal bin, conveying pipeline, dust separator, fine dust conveying pipe and bag collection bin;

The top of the dust removal bin communicates with the bottom of the dust separator;

The upper end of the dust separator communicates with the bag collection bin through the fine dust conveying pipe;

The conveying pipeline communicates with the dust separator.

Preferably, the dust separator includes:

Shell, annular delivery pipe, nozzle, support frame and diversion cone;

The annular conveying pipe is fixedly connected to the outer circumference above the housing; the annular conveying pipe communicates with the inside of the housing through the nozzle;

The support frame is arranged at the bottom of the housing; the diversion cone is fixedly connected to the support frame;

The conveying pipeline communicates with the annular conveying pipe;

The bottom of the housing communicates with the top of the dust removal bin.

As a preference, the nozzles are evenly distributed along the annular conveying pipe, and the number is 10-30 groups;

The central position of the nozzle gradually descends along the annular conveying pipe.

Preferably, the small end of the diversion cone is upward; the conical surface of the diversion cone is vertical and uniformly distributed with multiple rows of holes with a diameter of 5-20mm; the holes are distributed on the diversion cone with a height of 1/5-4 /5 position.

As preferably, the bag collection bin includes:

Silo body, relief valve, relief pipe, cloth bag and ash discharge valve;

The bin body includes: a lower cone and an upper cylinder;

The bottom end of the cone is provided with a discharge port; the dust discharge valve is provided on the discharge port; the fine dust conveying pipe is fixedly connected to the middle of the cylinder;

The release pipe communicates with the top of the cylinder; the entrance where the release pipe communicates with the warehouse body is fixedly connected to the cloth bag;

The relief valve is arranged on the relief pipe;

The release valve is used to adjust the release flow rate of the conveying gas filtered by the bag, control the size of the collected dust particles, and adjust the content of harmful elements such as alkali and zinc in the recyclate.

The device for separating harmful elements such as alkali and zinc in the blast furnace dry dedusting ash provided by the invention separates the dedusting ash into large particle dust containing less harmful elements such as alkali and zinc and less harmful elements such as alkali and zinc by setting a dust separator High small particle dust; the large particle dust is collected by setting the dust removal ash bin for sintering recycling; the small particle dust in the dust removal ash is collected in the bag by setting the bag collection bin, so most of the zinc oxide in the dust removal ash can be recovered Used as zinc raw material. At the same time, the device can be matched with the existing dry dust removal system.

A method for separating harmful elements such as alkali zinc in blast furnace dry dust removal ash provided by the invention comprises:

Spray the dedusted ash through the conveying pipeline into the dust separator by using a warehouse pump;

The large particles of dust in the dedusting ash fall to the bottom of the dust separator under the action of gravity, and then fall into the dedusting ash bin;

The small particle dust in the dedusting ash is introduced into the fine dust conveying pipe along with the airflow, and then enters the bag collection bin;

The dedusting ash with small dust particles is obtained through the bag collection bin, that is, the separation of large dust particles and small dust particles in the dedusting dust is realized.

As a preference, the use of a bin pump to spray the dedusted ash into the dust separator through the delivery pipeline includes:

The dedusting ash is sprayed into the annular conveying pipe through the conveying pipe; the dedusted ash enters the housing through the nozzle arranged on the annular conveying pipe.

As a preference, the large particles of dust in the dedusting ash fall to the bottom of the dust separator under the action of gravity, and then fall into the dedusting ash bin, including:

The dust particles in the dedusting ash entering the housing are sprayed onto the conical surface of the diversion cone;

Part of the dust particles can enter the central part of the diversion cone through the hole on the cone surface of the diversion cone, directly settle to the bottom of the housing, and then fall into the dust removal bin ;

Another part of the dust particles slides down the conical surface of the diversion cone, falls from the lower part of the diversion cone to the bottom of the housing, and then falls into the dust removal bin.

As a preference, the small particle dust in the dust removal ash is introduced into the fine dust conveying pipe along with the airflow, and then enters into the bag collection bin, including:

The dedusted ash containing small particles of dust is brought into the upper space of the dust separator by the conveying gas and the airflow rising from the hole on the cone surface of the diversion cone;

The dedusted ash containing small particle dust is introduced into the bag collection bin through the fine dust conveying pipe.

As preferably, the dedusting ash with small dust particles is obtained through the bag collection bin, including:

When the dedusting ash containing small particle dust passes through the bag at the top of the bag collection bin, the small particle dust in the dedusting ash is collected by the cloth bag, and the collected small particle dust can be recovered use;

The gas after the dust is filtered by the bag is discharged into the atmosphere through the release pipe and the release valve.

The method for separating harmful elements such as alkali zinc in blast furnace dry dedusting ash provided by the invention is processed by blast furnace dry dedusting ash, which overcomes the problems of complex equipment, difficult operation and high requirements for post-processing of products in the wet process, and provides Blast furnace dry dust removal method provides a small investment and stable process for the separation of harmful elements such as alkali and zinc. Not only can most of the zinc oxide in the dust removal dust be recovered as raw materials for zinc production, but through practical testing, the remaining dust containing zinc oxide can be controlled Below 2.0%, all can be recovered for sintering production.

Description of drawings

Fig. 1 is a general diagram of a device for separating harmful elements such as alkali and zinc in blast furnace dry dedusting ash provided by an embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view of a dust separator provided by an embodiment of the present invention.

Fig. 3 is a structural schematic diagram of a dust separator, a dust bin and a fine dust conveying pipe provided by an embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a bag collection bin provided by an embodiment of the present invention.

Detailed ways

Referring to accompanying drawing 1, a kind of device that the present invention provides for separating harmful elements such as alkali zinc in blast furnace dry dedusting ash comprises: dedusting ash bin 1, conveying pipeline 2, dust separator 3, fine dust conveying pipe 4 and cloth bag collecting bin 5. The top of the dust removal bin 1 communicates with the bottom of the dust separator 3; the upper end of the dust separator 3 communicates with the bag collection bin 5 through the fine dust conveying pipe 4; the conveying pipe 2 communicates with the dust separator 3.

Referring to accompanying drawings 2 and 3, as a preference, the dust separator 3 includes: a housing, an annular conveying pipe 31, a nozzle 32, a support frame 33 and a diversion cone 34; the annular conveying pipe 31 is fixedly connected to the outer circumference above the housing Above; the annular conveying pipe 31 communicates with the interior of the housing through the nozzle 32; the support frame 33 is arranged at the bottom of the housing; the diversion cone 34 is fixedly connected to the support frame 33; the conveying pipe 2 communicates with the annular conveying pipe 31; the bottom of the housing It communicates with the top of the dust removal ash bin 1.

Referring to accompanying drawing 2 and 3, as preferably, nozzle 32 is evenly distributed along annular conveying pipe 31, and quantity is 10～30 groups; down. As a preferred embodiment, the nozzles 32 are evenly distributed along the horizontal plane of the annular delivery pipe 31, and there are 20 groups of nozzles 32; the nozzles 32 are rectangular 20x40mm; The upper edge of the pipeline 31 has the same height, and the lower edge of the last nozzle 32 is the same as the lower edge of the annular delivery pipeline 31, and its central position gradually descends along the annular delivery pipeline 31, forming an oblique line. The nozzles 32 arranged in a circle can fully expand, atomize and classify the conveyed dust in the dust separator 3 without changing the flow rate and pressure of the conveyed gas, so as to achieve effective separation of coarse and fine powder particles.

As preferably, the small end of the diversion cone 34 is upward; the conical surface of the diversion cone 34 is vertical and uniformly distributed with a diameter of 5 to 20 mm rows of holes; the holes are distributed on the diversion cone 34 with a height of 1/5 to 4/5 Location. As a preferred embodiment, the cone surface of the diversion cone 34 is uniformly divided into holes with a diameter of 12mm, which are distributed in the upper 1/5 to the lower 1/5 of the cone, and are evenly distributed in a row along the cone surface with an interval of 50mm. Centers are horizontally spaced 50mm apart. Because the diversion cone 34 is set, the large particle dust in the dust removal ash can settle to the surface of the diversion cone 34 under the action of gravity, slide to the bottom of the dust separator 3 along the cone surface, and then fall into the dust removal ash bin 1; The fine particle dust in the dust is brought into the upper part of the dust separator 3 by the gas conveying the dedusting ash and the updraft, and enters the bag collection bin 5 through the fine dust conveying pipe 4, and then is recovered by the bag 54. The airflow rising from the hole disperses the dust again and brings the fine particle dust into the upper space.

Referring to accompanying drawing 4, preferably, cloth bag collection bin 5 comprises: bin body 51, release valve 52, release pipe 53, cloth bag 54 and ash unloading valve 55; Bin body 51 includes: the cone of lower part, the cylinder of upper part; The bottom end of the body is provided with a discharge port; the dust discharge valve 55 is arranged on the discharge port; the fine dust conveying pipe 4 is fixedly connected to the middle part of the cylinder; the discharge pipe 53 is connected with the top of the cylinder; Connect the cloth bag 54; the release valve 52 is set on the release pipe 53; the release valve 52 is used to adjust the release flow rate of the transport gas filtered by the cloth bag 54, control the size of the collected dust particles, and adjust the harmful elements such as alkali and zinc in the recyclate content.

The device for separating harmful elements such as alkali and zinc in blast furnace dry dedusting ash provided by the present invention separates dedusting ash into large particle dust containing less harmful elements such as alkali and zinc and harmful elements such as alkali and zinc by setting a dust separator 3 Higher small particle dust; by setting the dust removal bin 1, the large particle dust is collected for sintering and recycling; by setting the bag 54, the small particle dust in the dust removal ash is collected in the bag collection bin 5, so it can be recycled in the dust removal ash Most zinc oxide is used as raw material for zinc production. At the same time, the device can be matched with the existing dry dust removal system.

A method for separating harmful elements such as alkali and zinc in blast furnace dry dedusting ash provided by the present invention comprises: using a warehouse pump to spray the dedusting ash into the dust separator 3 through the conveying pipeline 2; Under the action of gravity, it falls to the bottom of the dust separator 3, and then falls into the dedusting ash bin 1; the small particles of dust in the dedusting ash are introduced into the fine dust conveying pipe 4 along with the airflow, and then enter into the bag collection bin 5; Bin 5 obtains dedusting ash with small dust particles, which realizes the separation of large particles of dust and small particles of dust in the dedusting ash.

As a preference, using a warehouse pump to spray the dedusting ash into the dust separator 3 through the conveying pipeline 2 includes: the dedusting ash is sprayed into the annular conveying pipe 31 through the conveying pipe 2; Nozzle 32 enters the housing.

As preferably, the large particle dust in the dedusting ash falls to the bottom of the dust separator 3 under the action of gravity, and then falls into the dedusting ash bin 1, including: the dust particles entering the dedusting ash in the housing are blown into On the cone surface of the diversion cone 34; part of the dust particles can enter the center of the diversion cone 34 through the holes on the cone surface of the diversion cone 34, directly settle to the bottom of the housing, and then fall into the dust bin 1; the other part of the dust particles slides down the cone surface of the diversion cone 34, falls from the lower part of the diversion cone 34 to the bottom of the housing, and then falls into the dust bin 1.

As preferably, the small particle dust in the dust removal ash is introduced into the fine dust conveying pipe 4 along with the air flow, and then enters the bag collection bin 5, including: the dust removal dust containing the small particle dust is transported by the gas and from the guide cone 34 conical surface The airflow rising from the hole is brought into the upper space of the dust separator 3; the dedusting ash containing small particles of dust is introduced into the bag collection bin 5 through the fine dust conveying pipe 4.

As preferably, obtain the little dedusting ash of dust particle by bag collecting bin 5, comprise: when the dedusting ash containing small particle dust passes through the cloth bag 54 on the top of bag collecting bin 5, the small particle dust in the dedusting ash is collected by cloth bag 54, simultaneously The collected small particles of dust can be recycled; the dust filtered by the bag 54 is discharged into the atmosphere through the release pipe 53 and the release valve 52 .

The method for separating harmful elements such as alkali zinc in blast furnace dry dedusting ash provided by the invention is processed by blast furnace dry dedusting ash, which overcomes the problems of complex equipment, difficult operation and high requirements for post-processing of products in the wet process, and provides Blast furnace dry dust removal method provides a small investment and stable process for the separation of harmful elements such as alkali and zinc. Not only can most of the zinc oxide in the dust removal dust be recovered as raw materials for zinc production, but through practical testing, the remaining dust containing zinc oxide can be controlled Below 2.0%, all can be recovered for sintering production.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. a device that separates the harmful element such as alkali zinc in blast furnace dry method dust ash, is characterized in that, comprising:

Dedusting ash silo, conveyance conduit, dust separator, fine dust carrier pipe and cloth bag collecting bin;

The top of described dedusting ash silo is communicated with the bottom of described dust separator;

The upper end of described dust separator is communicated with described cloth bag collecting bin by described fine dust carrier pipe;

Described conveyance conduit is communicated with described dust separator.

2. device according to claim 1, is characterized in that, described dust separator comprises:

Housing, annular duct, nozzle, bracing frame and deflection cone;

Described annular duct is connected on the excircle of described housing top; Described annular duct is communicated with described enclosure interior by described nozzle;

Support frame as described above is arranged on described housing bottom; Described deflection cone is connected on support frame as described above;

Described conveyance conduit is communicated with described annular duct;

Described housing bottom is communicated with the top of described dedusting ash silo.

3. device according to claim 2, is characterized in that:

Described nozzle is uniformly distributed along described annular duct, and quantity is 10～30 groups;

Described nozzle center is descending gradually along described annular duct.

4. device according to claim 2, is characterized in that:

The small end of described deflection cone upwards; The conical surface of described deflection cone is vertical, be uniformly distributed many rounds hole that diameter is 5～20mm; Described hole is distributed in the position of height 1/5～4/5 on deflection cone.

5. device according to claim 1, is characterized in that, described cloth bag collecting bin comprises:

Warehouse, diffusion valve, exhaust stack, cloth bag and unloading valve;

Described warehouse comprises: the cone of bottom, the cylinder on top;

Described cone bottom arranges outlet; Described unloading valve is arranged on described outlet; Described fine dust carrier pipe is connected in described cylindrical middle part;

Described exhaust stack is communicated with described cylinder top; The porch that described exhaust stack is communicated with the described warehouse described cloth bag that is connected;

Described diffusion valve is arranged on described exhaust stack;

Described diffusion valve, for regulating the flow that diffuses of conveying gas after Bag filter, is controlled the dust granules size of collecting, and regulates the content of the harmful elements such as alkali, zinc in regenerant.

6. a method that separates the harmful element such as alkali zinc in blast furnace dry method dust ash, is characterized in that, comprising:

Use cone pump that dedusting ash is sprayed in dust separator claimed in claim 1 by conveyance conduit claimed in claim 1;

Big dust particle in described dedusting ash drops to the bottom of described dust separator at Action of Gravity Field, and then drops in dedusting ash silo claimed in claim 1;

Granule dust in described dedusting ash is incorporated in fine dust carrier pipe claimed in claim 1 with air-flow, then enters in the cloth bag collecting bin described in claim 1;

Obtain the little dedusting ash of dust granules by described cloth bag collecting bin, realized separating of the big dust particle in dedusting ash and granule dust.

7. method according to claim 6, is characterized in that, described utilization cone pump sprays into dedusting ash in dust separator claimed in claim 1 by conveyance conduit claimed in claim 1, comprising:

Described dedusting ash sprays in annular duct claimed in claim 2 by described conveyance conduit; Described dedusting ash enters into described housing by the nozzle claimed in claim 2 being arranged in annular duct.

8. method according to claim 6, is characterized in that, the big dust particle in described dedusting ash drops to the bottom of described dust separator at Action of Gravity Field, and then drops in dedusting ash silo claimed in claim 1, comprising:

The dust granules that enters into the dedusting ash of described housing is blowed on the conical surface of deflection cone claimed in claim 2;

Wherein a part of dust of described dust granules can enter by the hole on the conical surface of described deflection cone the centre of described deflection cone, is directly deposited to the bottom of described housing, and then falls into described dedusting ash silo;

Another part of described dust granules glides along the conical surface of described deflection cone, falls the bottom of described housing, and then fall into described dedusting ash silo from the bottom of described deflection cone.

9. method according to claim 6, is characterized in that, the granule dust in described dedusting ash is incorporated in fine dust carrier pipe claimed in claim 1 with air-flow, then enters in the cloth bag collecting bin described in claim 1, comprising:

The described dedusting ash that contains granule dust is transferred air-flow that gas and the hole from the described deflection cone conical surface rise brings the upper space of dust separator claimed in claim 1 into;

The described dedusting ash that contains granule dust is incorporated in described cloth bag collecting bin by fine dust carrier pipe claimed in claim 1.

10. method according to claim 6, is characterized in that, obtains the little dedusting ash of dust granules by described cloth bag collecting bin, comprising:

When the claimed in claim 5 cloth bag of the described dedusting ash that contains granule dust by described cloth bag collecting bin top, the granule dust in described dedusting ash is collected by described cloth bag, and the granule dust being collected described in simultaneously can be recovered utilization;

The gas of described dedusting ash after by described Bag filter enters in atmosphere by exhaust stack claimed in claim 5 and diffusion valve.