CN113333145B

CN113333145B - Bag-type dedusting ash separation process

Info

Publication number: CN113333145B
Application number: CN202110757195.4A
Authority: CN
Inventors: 刘会岗
Original assignee: Shexian Baoxuan Machinery Equipment Co ltd
Current assignee: Shanxi Tongcai Industry and Trade Co Ltd
Priority date: 2021-07-05
Filing date: 2021-07-05
Publication date: 2022-03-29
Anticipated expiration: 2041-07-05
Also published as: CN113333145A

Abstract

The invention relates to the technical field of mineral processing, and provides a process for sorting bag-type dedusting ash in a steel mill, which comprises the following steps that fluid materials enter a diaphragm pump for grinding, ground mortar is lifted to a high-frequency screen by a grinding pulping machine, undersize materials of the high-frequency screen automatically flow to an elutriation machine for sorting, foaming agents and collecting agents are added into tailing slurry discharged from the elutriation machine, the tailing slurry enters an mineralization tank, the mineralized mixture enters a first flotation machine and a second flotation machine, then the mineralized mixture enters a first flow film gravity separation machine, the first flow film gravity separation machine generates three products which are respectively iron powder, middlings and tailings, and carbon powder, iron powder, tailing cakes and salt are further sorted.

Description

Bag-type dedusting ash separation process

Technical Field

The invention relates to the technical field of mineral processing, in particular to a sorting process of cloth bag dedusting ash in a steel mill.

Background

The bag-type dedusting ash of the blast furnace is solid particles discharged by the iron-making blast furnace in the smelting process, and can cause great pollution to the environment if being treated as waste, and also can occupy great plant space, and the bag-type dedusting ash has high recycling value and is also great waste to resources if being treated as waste.

The existing separation process for the blast furnace cloth bag dust is insufficient in recovery, most of the separation process can only separate valuable elements such as carbon, iron, zinc and the like from the blast furnace cloth bag dust, and the rest of the separation process is still treated according to waste materials, so that the recovery of the blast furnace cloth bag dust is insufficient.

Disclosure of Invention

The invention provides a bag dedusting ash separation process, which solves the problem of the bag dedusting ash separation process in the related technology.

The technical scheme of the invention is as follows:

the bag dedusting ash separation process comprises the following steps:

step A, putting raw materials into a bin, feeding the raw materials into a spiral stirrer through a feeder, adding water and stirring the raw materials into a fluid state,

step B, feeding the fluid material into a crushing pulping machine, adding water for polishing, automatically flowing to a high-frequency sieve through a diaphragm pump through a stirring mill,

c, returning the oversize materials of the high-frequency sieve to the diaphragm pump for grinding, repeating the step B, pumping the undersize materials of the high-frequency sieve into the elutriation machine by a submerged pump for separation, providing clear water for the elutriation machine by a clear water tank in the elutriation process,

d, selecting iron powder and tailing slurry by the elutriation machine, adding a foaming agent and a collecting agent into the tailing slurry, feeding the mixture into an mineralization tank, mineralizing the mixture and feeding the mineralized mixture into a first flotation machine, selecting the floating matter produced by the first flotation machine in a second flotation machine, feeding the selected floating matter obtained by the second flotation machine into a first flow film gravity separator, generating three products, namely iron powder, middlings and tailings, by the first flow film gravity separator, providing clear water for the second separator and the first flow film gravity separator by a clear water tank,

step E, sorting carbon powder, namely, feeding tailings generated by the first flow film gravity separator into a flat magnetic separator to remove iron-containing particles, lifting tailing slurry to a carbon powder storage bin by a carbon powder pump, thickening and stirring, removing redundant clear water at the upper part after thickening, adding sulfuric acid for stirring, feeding underflow into a vacuum belt filter for dehydration after zinc dissolution, dropping dehydrated carbon powder into a carbon powder bin to obtain a carbon powder product,

f, pumping the tail mortar floated by the first flotation machine into a cyclone group by a slurry pump for separation, adding a flocculating agent into the overflow through a pipeline, then feeding the overflow into a dense pool, feeding the sediment outlet product into a gravity separation machine distribution box, uniformly feeding the distribution box into a second flow film gravity separation machine, wherein the second flow film gravity separation machine generates three products which are respectively iron powder, middlings and tailings, and a clean water tank provides clean water for the second flow film gravity separation machine,

g, sorting iron powder, combining the iron powder selected in the step D and the step F, lifting the combined iron powder to an iron powder thickening tank through an iron powder pump, thickening and stirring, removing the redundant clear water on the upper layer after thickening, adding sulfuric acid for stirring, after zinc is dissolved, enabling the underflow to flow into a vacuum belt filter again, and dehydrating to obtain iron powder,

step H, sorting the tail mud cakes, adding a flocculating agent into the overflow of the cyclone in the step F, feeding the overflow into a thickening tank, introducing the underflow into a stirring barrel by a crushing pulping machine after concentration, adding sulfuric acid for stirring, flowing the tail mud into a vacuum belt filter after zinc is dissolved, and dehydrating to obtain the tail mud cakes,

and step I, salt separation, namely feeding the water in the clean water tank into reverse osmosis equipment for purification when the salt concentration of the water is close to saturation, returning the purified water to the clean water tank for recycling, and feeding the concentrated water generated by reverse osmosis into a triple-effect evaporator to obtain the product salt.

As a further technical solution, in the step D, the second flotation machine performs concentration six times in total.

As a further technical scheme, in the step F, tailings generated by the second flow membrane gravity separator return to the crushing and pulping machine, and are circularly sorted.

As a further technical solution, in the step D, middlings generated by the first fluidized bed gravity separator and the flat magnetic separator in the step E are returned to the crushing and pulping machine in the step B, and are circularly sorted.

As a further technical scheme, in the step D, the tailings generated by the second flotation machine are returned to the diaphragm pump for grinding and circular separation in the step B.

And as a further technical scheme, in the step H, after the overflow of the cyclone and the flocculating agent enter the thickening tank, the clear water at the upper part automatically flows to the clear water tank for recycling.

As a further technical proposal, the method also comprises

And step J, recycling the filtrate, wherein in the step E, the step G and the step H, the acid-containing filtrate flowing out of the vacuum belt filter is sent to a collecting tank by a sewage pump, alkali is added for neutralization, and the precipitate is fed into a filter press by a crushing pulping machine for dehydration to obtain a zinc-containing product.

In the step J, the filtrate dehydrated by the filter press flows into the thickening tank in the step H for recycling.

The working principle and the beneficial effects of the invention are as follows:

the method has the greatest advantage that almost no emission exists, the blast furnace cloth bag dust can be recycled to the greatest extent, valuable elements such as carbon, iron and zinc can be recycled through the improved process, the tail mud cake and salt can be separated and recycled on the basis, the dehydrated tail mud cake can contain 45% of iron and zinc to be reduced to below double zero through dehydration of the vacuum belt filter and continuous circular separation, and different types of products can be separated to the greatest extent.

The recovery of the tail mud cake can be used by a blast furnace or used as a correction agent in a cement plant, and the product is recycled. For the separation of salt products, on one hand, because the steel mill fly ash is rich in chloride ions, potassium and sodium, the element molecules can be dissolved into water in the water washing process, and the water is recycled in the production process, the water can reach a saturated state quickly, and finally the produced products are caused to have excessive harmful elements, so that the salts in the water can be extracted after the water is purified, the water resource can be saved, and the water can be recycled.

Furthermore, tailings generated by the second flow membrane gravity separator, middlings generated by the first flow membrane gravity separator and the flat magnetic separator in the step E are returned to the crushing pulping machine, tailings generated by the second flotation machine are returned to the diaphragm pump for grinding, and the circulating steps ensure that the tail mud cake hardly contains iron, zinc and carbon, can ensure the recyclability of the tail mud cake, and can enable more iron, zinc and carbon to be produced. The further two devices of the crushing pulping machine and the diaphragm pump do not supplement clear water, and water resources are fully saved and utilized.

In the step I, when the salt content of water in the clean water tank reaches a certain concentration, the water is jacked up by a pipeline and fed into a concentrated salt tank for storage, and the water is fed into a reverse osmosis device by the concentrated salt tank and then fed into a triple-effect evaporator to obtain product salt. The steel mill fly ash is rich in chloride ions, potassium and sodium, and in the water washing process, the elements can be dissolved in water and recycled in the production process, so that the steel mill fly ash can reach a saturated state quickly, and finally, the produced harmful elements exceed the standard, and therefore, desalting treatment is required.

All can produce the waste material when the blast furnace sack dust removal ash of prior art is retrieved, need further processing, but conventional cognition has been broken to the technology after this application improves, nearly no waste material in blast furnace sack dust removal ash recovery process, the possibility that can recycle in the production process has been excavated as far as possible, lower water resource consumption has been accomplished, the kind of thing of producing simultaneously is the most, the product has carbon, iron, zinc, tail mud and salt, water also is one of the product, these all can be retrieved and recycled, wherein the output of carbon, iron, zinc has improved 10% ~ 40%.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a schematic view of the structure of the present invention;

FIG. 2 is a schematic view of another filtrate recovery scheme according to the present invention;

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to 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 inventive step, are intended to be within the scope of the present invention.

Example 1

As shown in fig. 1, the present embodiment proposes

The bag dedusting ash separation process comprises the following steps:

step A, the raw materials are discharged into a spiral stirring conveyor filled with spray water by a conveying vehicle and conveyed to a raw material yard for stacking, the raw materials are added with water to prevent raising dust, the raw materials are put into a storage bin through a crane grab bucket and then are uniformly fed into a spiral stirrer by a disc feeder to be added with water and stirred into a fluid state,

c, returning the oversize material of the high-frequency sieve to the diaphragm pump for grinding, repeating the step B, pumping the undersize material of the high-frequency sieve into the elutriation machine by a submerged pump for separation, providing clear water for the elutriation machine by a clear water tank in the elutriation process,

d, selecting iron powder and tailing slurry by the elutriation machine, adding a foaming agent and a collecting agent into the tailing slurry, feeding the mixture into an mineralization tank, mineralizing the mixture, feeding the mineralized mixture into a first flotation machine, selecting the floating matter produced by the first flotation machine into a second flotation machine, performing six-time selection by the second flotation machine, returning the tailing produced by the second flotation machine to the diaphragm pump for grinding and circular selection, feeding the floating matter selected by the second flotation machine into a first flow film gravity selector, generating three products, namely iron powder, middlings and tailings by the first flow film gravity selector, and providing clear water for the second flotation machine and the first flow film gravity selector by a clear water tank,

e, separating carbon powder, namely, feeding tailings generated by the first flow film gravity separator into a flat magnetic separator to remove iron-containing particles, feeding middlings generated by the first flow film gravity separator in the step D and middlings generated by the flat magnetic separator in the step E back to the crushing pulping machine in the step B, circularly separating, lifting tailing slurry generated by the flat magnetic separator to a carbon powder storage bin by a carbon powder pump, thickening and stirring, removing redundant clear water on the upper part after thickening, adding sulfuric acid for stirring, feeding underflow into a vacuum belt filter for dehydration after zinc is dissolved, and dropping the dehydrated carbon powder into the carbon powder bin to obtain a carbon powder product,

f, pumping the tail mortar floated by the first flotation machine into a cyclone group by a slurry pump for separation, adding a flocculating agent into the overflow through a pipeline, then feeding the overflow into a thickening tank, feeding the sediment outlet product into a gravity separator distribution box, uniformly feeding the distribution box into a second flow film gravity separator, wherein the second flow film gravity separator generates three products which are respectively iron powder, middlings and tailings, the tailings generated by the second flow film gravity separator are returned into a crushing pulping machine for circular separation, and a clean water tank provides clean water for the second flow film gravity separator,

g, sorting iron powder, combining the iron powder selected in the step D and the step F, lifting the combined iron powder to an iron powder thickening tank through an iron powder pump, thickening and stirring, removing the redundant clear water on the upper layer after thickening, adding sulfuric acid for stirring, dissolving zinc, then making the bottom flow into a vacuum belt filter, dewatering to obtain iron powder, dewatering to obtain the iron powder with the taste of more than 60 percent, reducing the zinc content to below double zero,

step H, sorting the tail mud cakes, adding a flocculating agent into the overflow of the cyclone in the step F, feeding the overflow into a thickening tank, introducing the underflow into a stirring barrel by a crushing pulping machine after concentration, adding sulfuric acid for stirring, flowing the tail mud into a vacuum belt filter after zinc oxide is dissolved, dehydrating to obtain the tail mud cakes, wherein the iron content of the dehydrated tail mud cakes is 45 percent, and the zinc content is reduced to below double zero,

In this embodiment, the most obvious advantage lies in hardly having the emission, furthest retrieves blast furnace sack fly ash and recycles, through improving technology, not only can realize retrieving valuable elements such as carbon, iron and zinc, can also select separately the recovery to tail mud cake and salt on this basis, through the dehydration of vacuum belt filter to and constantly circulate and select separately, can make the tail mud cake iron content 45% and zinc after the dehydration fall to below double zero, can guarantee the very big separation of different types of product.

All can produce the waste material when the blast furnace sack dust removal ash of prior art is retrieved, need further processing, but conventional cognition has been broken to the technology after this application improves, nearly no waste material in blast furnace sack dust removal ash recovery process, the possibility that can recycle in the production process has been excavated as far as, lower water resource consumption has been accomplished, the kind of thing of producing simultaneously is the most, the product has carbon, iron, zinc, tail mud and salt, water is also one of the product, these all can be retrieved and recycled, wherein the output of carbon, iron, zinc has improved 10% ~ 40%, iron powder more than%.

Example 2

As shown in fig. 1, based on the same concept as in example 1, a step of collecting and collecting the filtrate collectively is also proposed in addition to example 1.

The method also comprises a step J on the basis of the embodiment 1,

and D, recycling the filtrate and sorting the zinc products, wherein in the step E, the step G and the step H, the acid-containing filtrate flowing out of the vacuum belt filter is sent to a collecting tank by a sewage pump, alkali is added for neutralization, and the precipitate is fed into a filter press by a crushing pulping machine for dehydration to obtain the zinc-containing product.

In the embodiment, zinc products can be further separated in the recovery process of carbon powder, iron powder and tail mud cakes, and meanwhile, filtrate of the vacuum belt filter is collected, so that random discharge of sewage is prevented, and environmental pollution is reduced.

Furthermore, in the step E, the step G and the step H, sulfuric acid is added for stirring, acid is preferred, then alkali neutralization is carried out, sewage can be further recycled, the zinc content of the recycled carbon powder, iron powder and tail mud cake is extremely low, and the zinc content is reduced to below double zero.

Example 3

As shown in fig. 1, based on the same concept as in example 2 above, the dehydration filtrate was further recycled based on example 2.

In particular, the method comprises the following steps of,

in step J, the filtrate dehydrated by the filter press flows into the thickening tank in step H for recycling.

In the step H, clear water at the upper part of the thickening tank automatically flows to a clear water tank for recycling.

In the embodiment, the recovery rate of clean water can be improved, the yield of the tail mud in the subsequent step of concentrating the underflow in the concentration tank in the step H can be improved, the yield of zinc products after filtrate recovery is realized after the tail mud flows into the vacuum belt filter, circular separation can be realized, and the yield of each product is improved.

Example 4

As shown in fig. 2, based on the same concept as that of the above-described embodiment 1, another process of collecting and collecting the filtrate collectively is proposed in addition to the embodiment 1. The difference from example 2 is that acid-base neutralization is not performed. And D, recycling the filtrate and sorting the zinc products, wherein in the step E, the step G and the step H, the filtered acid-containing filtrate is sent into a collecting tank by a sewage pump, the solution recovered by the collecting tank is subjected to reverse osmosis treatment, the purified water enters a thickening tank, the thickened water enters an evaporator for evaporation and concentration, and the zinc-containing product is obtained by spin-drying through a centrifuge.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The bag dedusting ash separation process is characterized by comprising the following steps:

g, sorting iron powder, combining the iron powder selected in the step D and the step F, lifting the combined iron powder to an iron powder thickening tank through an iron powder pump, thickening and stirring, removing the redundant clear water on the upper layer after thickening, adding sulfuric acid for stirring, dissolving zinc oxide, then making the bottom flow into a vacuum belt filter, dewatering to obtain iron powder,

2. The bag dedusting ash separation process of claim 1, wherein in step D, the second flotation machine performs six beneficiation steps in total.

3. The bag dedusting ash separation process of claim 2, wherein in the step F, the second flow film gravity separator produces tailings, the tailings are returned to the crushing pulping machine, and the separation is performed in a circulating manner.

4. The bag dedusting ash separation process of claim 2, wherein middlings generated by the first fluidized bed gravity separator and the flat magnetic separator in step E in step D are returned to the crushing and pulping machine in step B for circular separation.

5. The bag dedusting ash separation process of claim 2, wherein in the step D, the tailings generated by the second flotation machine are returned to the diaphragm pump grinding and circulated for separation in the step B.

6. The bag-type fly ash sorting process according to claim 1, wherein in the step H, after the overflow of the cyclone and the flocculant enter the thickening tank, the upper clear water automatically flows to a clear water tank for recycling.

7. The bag dedusting ash separation process of claim 1, further comprising

8. The bag dedusting ash separation process of claim 7, wherein in the step J, the filtrate dehydrated by the filter press flows into the thickening tank in the step H for recycling.