CN114956618B

CN114956618B - Cement kiln co-treatment fly ash system

Info

Publication number: CN114956618B
Application number: CN202210578146.9A
Authority: CN
Inventors: 裴程林; 姚源; 韩啸; 赵峰娃; 程占; 秦宗甲; 汪勇; 温亚菲; 王中华; 李宗阳; 李洋; 权登辉
Original assignee: Anhui Conch Environmental Protection Group Co ltd
Current assignee: Anhui Conch Environmental Protection Group Co ltd
Priority date: 2022-05-24
Filing date: 2022-05-24
Publication date: 2023-07-28
Anticipated expiration: 2042-05-24
Also published as: CN114956618A

Abstract

The invention discloses a cement kiln co-treatment fly ash system, which comprises: the device comprises a raw ash unit, a water washing unit, a drying unit, a kiln feeding unit, a water treatment unit and an evaporation salt making unit; the raw ash unit stores raw ash and can send the raw ash into the washing unit; the washing unit can wash the raw ash, and send the solid matters after washing into the drying unit and the liquid matters into the water treatment unit; the drying unit can be used for drying the cleaned solid matters correspondingly and sending the solid matters into the kiln feeding unit; the kiln feeding unit can collect and convey fixed substances; the water treatment unit can treat the liquid substance; the evaporation salt making unit can recycle salt in the liquid substance, the fly ash is treated by utilizing the cement kiln, and the residue can be directly used for cement production, so that the demand for natural resources is reduced, the damage to the environment and resources is reduced, the pollution and damage of waste to the social environment are reduced, and the cost of solid waste treatment is greatly reduced.

Description

Cement kiln co-treatment fly ash system

Technical Field

The invention belongs to the technical field of cement kilns, and particularly relates to a system for cooperatively disposing fly ash in a cement kiln.

Background

In carrying out the invention, the inventors have found that the prior art has at least the following problems:

because the waste incineration fly ash has higher chlorine content, the disposal mode of directly spraying into the cement kiln is simple and feasible, but because cement finished products have strict limits on chlorine content indexes, and kiln-entering materials have high chlorine content, the running safety of cement kiln equipment is seriously threatened, so that the disposal amount is very small, and the disposal requirement of the waste incineration fly ash can not be met far.

Disclosure of Invention

The invention aims to solve the technical problem of providing a cement kiln fly ash which can be directly used for cement production by utilizing the cement kiln to cooperatively treat fly ash, reduces the demand on natural resources, reduces the damage to environment and resources, reduces the pollution and damage of wastes to social environment, and greatly reduces the treatment cost of solid wastes.

In order to solve the technical problems, the invention adopts the following technical scheme: a cement kiln co-treatment fly ash system having:

the device comprises a raw ash unit, a water washing unit, a drying unit, a kiln feeding unit, a water treatment unit and an evaporation salt making unit;

the raw ash unit stores raw ash and can send the raw ash into the washing unit;

the washing unit can clean raw ash, and send the cleaned solid matters into the drying unit and the liquid matters into the water treatment unit;

the drying unit can be used for drying the cleaned solid matters correspondingly and sending the solid matters into the kiln feeding unit;

the kiln inlet unit can collect and convey fixed substances;

the water treatment unit can treat liquid substances;

the evaporation salt making unit can recover salt in the liquid substance.

The raw ash unit is provided with a raw ash bin, a feeder, a blanking device and a weighing device which are sequentially connected through pipelines, and raw ash of the raw ash unit is sent into the washing unit through the pipelines.

The water washing unit is provided with a plurality of water washing units which are sequentially connected through pipelines:

the mixer is connected with the weighing machine through a pipeline;

a premix tank;

a first wash tank;

a first solid-liquid separation device A;

a first solid-liquid separation device B;

the liquid of the first solid-liquid separation device A enters the first solid-liquid separation device B after being filtered by the first filter tank;

a second wash tank into which the solid matters of the first solid-liquid separation device A and the first solid-liquid separation device B enter; the liquid substance of the first solid-liquid separation device B enters the water treatment unit;

the second washing tank is communicated with the second solid-liquid separation device A through a pipeline;

the liquid substances of the second solid-liquid separation device A pass through the second filter tank and then enter the mixer;

the fixing device of the second solid-liquid separation device A enters the third washing buffer tank;

the third washing tank is communicated with the third washing buffer tank through a pipeline;

the third solid-liquid separation device A is communicated with the third washing tank through a pipeline;

the liquid substance of the third solid-liquid separation device A passes through the third filter tank and then enters the second washing tank through the first solid-liquid separation device A and the first solid-liquid separation device B; and solid matters of the third solid-liquid separation device A enter the drying unit.

The drying unit has:

a mixer; is connected with the third solid-liquid separation device A;

the dryer is connected with the mixer, and materials in the mixer enter the dryer;

a blower for blowing hot air into the dryer;

a dust removing cloth bag, wherein the materials dried by the dryer enter the dust removing cloth bag;

and a part of materials in the dedusting cloth bag enter the mixer through the back mixing bin, and the other part of materials are sent to the kiln entering unit.

The kiln feeding unit comprises a finished product ash bin, a finished product ash feeding kiln bin, a metering scale and a decomposing furnace which are sequentially connected through pipelines, and materials enter the decomposing furnace through the metering scale to be calcined.

The water treatment unit has:

the liquid substance of the first solid-liquid separation device B enters the first-stage sedimentation tank;

the liquid substances in the first-stage sedimentation tank enter the second-stage sedimentation tank, and the solid substances enter a filter tank;

the solid matters in the secondary sedimentation tank pass through the heavy solid-liquid removal separation device and then return to the secondary washing tank;

the liquid substance in the secondary sedimentation tank enters the secondary sedimentation water producing tank;

a decalcification tank, wherein liquid substances in the secondary precipitation water producing tank enter the decalcification tank;

the device comprises a sodium sulfate bin, a belt weighing machine and a sodium sulfate dissolving tank which are sequentially connected through pipelines, wherein sodium sulfate in the sodium sulfate dissolving tank enters the decalcification tank;

the materials in the decalcification tank enter the gypsum solid-liquid separation device; gypsum separated by the gypsum solid-liquid separation device enters a gypsum warehouse;

the liquid substance of the gypsum solid-liquid separation device enters the decalcification adjusting tank;

the liquid substance in the decalcification regulating tank enters the three-stage sedimentation tank;

a sodium carbonate solution tank for inputting sodium carbonate solution into the three-stage sedimentation tank;

a third-stage sedimentation water producing tank, wherein liquid substances in the third-stage sedimentation water producing tank enter the third-stage sedimentation water producing tank;

liquid substances in the three-stage precipitation water producing tank sequentially pass through the first-stage membrane device, the first-stage membrane water producing tank, the second-stage membrane device and the evaporation crystallization regulating tank and then enter the evaporation salt making unit.

The evaporation salt making unit has:

a pre-heat exchange plate, wherein materials in the evaporation crystallization adjusting tank enter the pre-heat exchange plate;

the falling film evaporator generates secondary steam which enters the compressor for circulation;

a forced circulation heating chamber and a crystallization separator, wherein liquid substances of the falling film evaporator enter the forced circulation heating chamber and the crystallization separator; the secondary steam generated by the crystallization separator enters a compressor for circulation, liquid substances generated by the compressor enter a forced circulation heating chamber, and solid substances generated by the crystallization separator enter a separation device, wherein the separation device comprises a sodium salt separation device and a potassium salt separation device;

the sodium salt separation device comprises:

the sodium salt solid-liquid separation device, the separated liquid device enters the potassium salt separation device; the solid matters separated by the sodium salt solid-liquid separation device sequentially enter a sodium salt washing device and a sodium salt second solid-liquid separation device, wherein the solid matters separated by the sodium salt second solid-liquid separation device are sodium chloride, and the liquid matters of the sodium salt second solid-liquid separation device enter a forced circulation heating chamber through a sodium salt mother liquor tank;

the potassium salt separation device comprises:

the potassium salt raw material tank, the potassium salt first-stage cooling device, the potassium salt second-stage cooling device and the potassium salt solid-liquid separation device are sequentially connected through pipelines, and a liquid device separated by the sodium salt solid-liquid separation device enters the potassium salt raw material tank;

the solid matters separated by the potassium salt solid-liquid separation device sequentially enter a potassium salt washing device and a potassium salt second solid-liquid separation device, and the solid matters separated by the potassium salt second solid-liquid separation device are potassium chloride; and the liquid substance separated by the potassium salt second solid-liquid separation device enters a forced circulation heating chamber through a potassium salt mother liquor tank.

The premixing tank comprises a premixing tank A and a premixing tank B which are connected in parallel; the first washing tank comprises a first washing tank A, a first washing tank B and a first washing tank C which are connected in parallel; the third washing tank comprises a third washing tank A and a third washing tank B which are connected in parallel; the decalcification tank comprises a decalcification tank A and a decalcification tank B which are connected in parallel.

One of the above technical solutions has the following advantages or beneficial effects that the fly ash is treated by the cement kiln, the residue of the fly ash can be directly used for cement production, the demand for natural resources is reduced, the damage to the environment and resources is reduced, the pollution and damage to the social environment by wastes are reduced, and the cost of solid waste treatment is greatly reduced.

Drawings

FIG. 1 is a schematic process flow diagram of a cement kiln co-treatment fly ash system provided in an embodiment of the invention;

FIG. 2 is a schematic process flow diagram of a water wash unit of the cement kiln co-treatment fly ash system of FIG. 1;

FIG. 3 is a schematic process flow diagram of a drying unit and a kiln entry unit of the cement kiln co-treatment fly ash system of FIG. 1;

FIG. 4 is a schematic process flow diagram of a water treatment unit of the cement kiln co-treatment fly ash system of FIG. 1;

FIG. 5 is a schematic process flow diagram of an evaporative salt-making unit of the cement kiln co-treatment fly ash system of FIG. 1;

the labels in the above figures are:

1. a raw ash unit;

2. a water washing unit 201, a double-screw mixer 202, a first premixing tank 203, a second premixing tank 204, a first washing tank A,205, a first washing tank B,206, a first washing tank C,207, a first solid-liquid separation device A,208, a first solid-liquid separation device B,209, a first filtering tank 210, a second washing tank 211, a second filtering tank 212, a second solid-liquid separation device A,213, a third washing buffer tank 214, a third washing tank A,215, a third washing tank B,216, a third solid-liquid separation device A,217 and a third filtering tank;

3. the device comprises a drying unit 301, a coulter mixer 302, a back mixing bin 303, a dryer 304, a blower 305, a dust removing cloth bag 306 and a draught fan;

4. kiln feeding unit 401, finished ash bin 402, finished ash bin 403, metering scale 404 and decomposing furnace;

5. the device comprises a water treatment unit 501, a primary sedimentation tank, 02, a secondary sedimentation tank, 503, a weight-removing solid-liquid separation device, 504, a sedimentation water producing tank, 505, a sodium sulfate bin, 506, a belt weighing machine, 507, a sodium sulfate dissolving tank, 508, a decalcification tank A,509, a gypsum solid-liquid separation device, 510, a decalcification adjusting tank, 511, a sodium carbonate solution tank, 512, a tertiary sedimentation tank, 513, a tertiary sedimentation water producing tank, 514, a primary membrane device, 515, a primary membrane water producing tank, 516, a secondary membrane device, 517 and an evaporation crystallization adjusting tank;

6. the device comprises an evaporation salt making unit 601, a pre-heat exchange plate 602, a condensate water tank, 603, a falling film evaporator 604, a crystallization separator 605, a compressor 606, a forced circulation heating chamber 607, a sodium salt solid-liquid separation device 608, a sodium salt washing device 609, a sodium salt second solid-liquid separation device 610, a sodium salt mother liquor tank 611, a sodium salt mother liquor tank 612, a potassium salt first-stage cooling device 613, a potassium salt second-stage cooling device 614, a potassium salt solid-liquid separation device 615, a potassium salt washing device 616, a potassium salt second solid-liquid separation device 617 and a potassium salt mother liquor tank.

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.

Referring to fig. 1-5, a cement kiln co-treatment fly ash system having:

the device comprises a raw ash unit, a water washing unit, a drying unit, a kiln feeding unit, a water treatment unit and an evaporation salt making unit; the raw ash unit stores raw ash and can send the raw ash into the washing unit; the washing unit can wash the raw ash, and send the solid matters after washing into the drying unit and the liquid matters into the water treatment unit; the drying unit can be used for drying the cleaned solid matters correspondingly and sending the solid matters into the kiln feeding unit; the kiln feeding unit can collect and convey fixed substances; the water treatment unit can treat the liquid substance; the evaporation salt making unit can recover salt in the liquid substance.

The technology of washing and desalting the fly ash and the cement kiln co-treatment is an engineering technology for producing cement by taking the fly ash after washing and dechlorination as a raw material, on one hand, the unique high-temperature environment of the cement kiln is utilized to stably detoxify the fly ash (dioxin, heavy metals and the like), on the other hand, the water after the water quality purification and evaporation treatment of the ash washing wastewater is utilized for recycling, thereby realizing recycling and saving part of cement production raw materials. The technology has good dechlorination effect, the fume emission reaches the standard, the heavy metals in the fly ash are fixedly melted in cement lattices, and dioxin is thoroughly removed; particularly, the technology has large fly ash treatment amount, and can maximally utilize the calcineable fly ash capacity of the cement kiln; and simultaneously, a large amount of precious potassium salt resources are recovered.

Because of the high temperature working condition and alkaline environment in the cement rotary kiln, the production process of the modern rotary kiln provides possibility for treating hazardous waste, thereby providing an effective way for comprehensively utilizing natural resources and protecting environment in the modern society.

The fly ash is treated by the cement kiln, and the residue can be directly used for cement production, so that the demand on natural resources is reduced, the damage to the environment and resources is reduced, the pollution and damage of waste to the social environment are reduced, and the cost of solid waste treatment is greatly reduced.

Raw ash in the fly ash storage bin is conveyed to a blanking metering unit to enter a pulping system, and quantitative water (supplementing water or filtrate collected after washing) is added according to the water-ash ratio of 3:1, and stirring and pulping are carried out. The prepared slurry enters a primary washing reactor for primary washing, the fly ash slurry in the primary washing reactor is pumped into a primary washing centrifuge for centrifugal dehydration through a special fly ash transfer pump, the dehydrated filter cake enters a secondary washing reactor, and the washing liquid enters a decalcification system. And (3) the slurry in the secondary washing tank enters a secondary centrifugal machine through pumping to carry out secondary washing centrifugal dehydration, a filter cake after secondary centrifugation enters a tertiary washing reactor, and is sent to a tertiary washing system after being stirred and mixed, and secondary washing liquid is recycled to the primary washing system. The filter residue after three-stage water washing is subjected to a drying and dust collecting system, the chlorine content of the fly ash after water removal is less than or equal to 1%, the water content is less than or equal to 5% and enters a finished product storage and conveying system, and the finished product is calcined in a cement kiln.

And after the materials are separated, the ash washing water enters a multi-stage water washing liquid purifying system. In the water washing liquid purifying system, the water washing liquid entering the decalcification system and the heavy metal removing system is subjected to physical-chemical reaction, then the decalcification water washing liquid is conveyed to the water washing liquid buffer system through the water quality stabilizing reaction system to be stored and precipitated, and the water washing liquid leaving the water washing liquid buffer system is sequentially conveyed to the evaporation salt making unit after passing through the multi-stage multi-medium filtering system, the neutralization reaction system and the multi-stage fine filtering system.

(1) Raw ash storage and conveying unit: the raw ash unit is provided with a raw ash bin, a feeder, a blanking device and a weighing device which are sequentially connected through pipelines, and raw ash of the raw ash unit is sent into the washing unit through the pipelines. Raw ash storage and conveying unit: the disc feeder and the dividing wheel blanking device are vertically arranged, the belt weighing machine can realize instantaneous metering, blanking is uniform, the process is simple, and impact in the sequencing batch blanking process can be avoided.

(2) And (3) a water washing unit: the water washing unit is provided with a plurality of water washing units which are sequentially connected through pipelines:

the mixer is connected with the weighing machine through a pipeline; a premix tank; a first wash tank; a first solid-liquid separation device A; a first solid-liquid separation device B; the liquid of the first solid-liquid separation device A enters the first solid-liquid separation device B after being filtered by the first filter tank; the second washing tank, the solid matters of the first solid-liquid separation device A and the first solid-liquid separation device B enter the second washing tank; the liquid substance of the first solid-liquid separation device B enters a water treatment unit;

the second washing tank is communicated with the second solid-liquid separation device A through a pipeline; the liquid substances of the second solid-liquid separation device A pass through the second filter tank and then enter the mixer;

the fixing device of the second solid-liquid separation device A enters the third washing buffer tank; the third washing tank is communicated with the third washing buffer tank through a pipeline; the third solid-liquid separation device A is communicated with a third washing tank through a pipeline; the liquid substance of the third solid-liquid separation device A passes through the third filter tank and then enters the first solid-liquid separation device A, the first solid-liquid separation device B and the second washing tank; the solid matters of the third solid-liquid separation device A enter a drying unit.

The water washing unit is divided into pre-dissolving, one washing, two washing and three washing

Pre-dissolving: two-stage pre-dissolving; the first section adopts a mixer, double screws push the mixture, and the raw ash is fed while the liquid is fed, and the metering and proportioning are completed at the same time;

two premixing tanks are connected in series in the second stage, so that the premixing dissolution time is increased, the full mixing of the fly ash is ensured, and the dissolution of chloride ions in the fly ash is facilitated;

the fly ash water-washing slurry is conveyed by a peristaltic pump, so that the probability of pipeline blockage can be effectively reduced;

the continuous premixing can effectively avoid the concentrated contact of ash and liquid caused by sequencing batch premixing, the equipment damage caused by the concentrated discharge of released gas, and the like

And (3) washing: the sequencing batch type water washing is adopted, so that the water washing time of the fly ash is increased, the full washing of the fly ash is ensured, and the dissolution of chloride ions in the fly ash is facilitated;

first solid-liquid separation a: a horizontal decanter centrifuge is adopted;

first solid-liquid separation B: a horizontal decanter centrifuge is adopted;

the two-stage separation is adopted, so that the water washing liquid is cleaner, and the treatment pressure of the rear water treatment unit is reduced;

in addition: first solid-liquid separation B: a filter press can be adopted, so that flocculant is not required, the running cost is reduced, and meanwhile, the filter press is more thoroughly separated, thereby being beneficial to the water treatment process;

and (3) second washing: the fly ash water-washing slurry is conveyed by a peristaltic pump, so that the probability of pipeline blockage can be effectively reduced;

second solid-liquid separation a: a horizontal decanter centrifuge is adopted;

and (3) third washing: the sequencing batch type water washing is adopted, so that the water washing time of the fly ash is increased, the full washing of the fly ash is ensured, and the dissolution of chloride ions in the fly ash is facilitated;

third solid-liquid separation a: adopting a horizontal decanter centrifuge, and enabling wet fly ash to enter a drying unit;

in addition: the third solid-liquid separation A adopts a filter press; the moisture content of the wet fly ash can be further reduced, so that a drying unit is eliminated, and the wet fly ash is directly sent into a cement kiln to prepare cement;

the premixing tank comprises a premixing tank A and a premixing tank B which are connected in parallel; the first washing tank comprises a first washing tank A, a first washing tank B and a first washing tank C which are connected in parallel; the third washing tank comprises a third washing tank A and a third washing tank B which are connected in parallel.

(3) The method comprises the following steps Drying unit and kiln feeding unit

The drying unit has:

a mixer; is connected with a third solid-liquid separation device A; the dryer is connected with the mixer, and materials in the mixer enter the dryer; a blower for blowing hot air into the dryer; a dust removing cloth bag, wherein the materials dried by the dryer enter the dust removing cloth bag; and a part of materials in the dedusting cloth bag enter the mixer through the back mixing bin, and the other part of materials are sent to the kiln entering unit.

(4) The method comprises the following steps And (3) a water washing unit: removing heavy weight, gypsum, decalcification and membrane separation

The water treatment unit has:

Removing the weight: the two-stage sedimentation tanks are connected in series, and heavy metal ions in the water washing liquid are removed by adding a coagulant and adjusting PH to sediment heavy metal;

after the precipitated heavy metal ions are subjected to solid-liquid separation, the solid phase enters a water washing unit through a secondary water washing tank, and the liquid phase returns to a sedimentation tank;

the heavy metal mud is conveyed by adopting a positive displacement pump, so that the probability of pipeline blockage can be effectively reduced;

removing heavy solid-liquid separation: a centrifugal solid-liquid separator is adopted;

in addition: the solid-liquid separation for removing heavy weight adopts filter pressing type separation, and solid phase needs to be pre-dissolved and then enters a water washing unit through a secondary water washing tank;

gypsum: the sodium sulfate reacts with calcium ions in the fly ash water washing liquid to generate slightly soluble calcium sulfate, so that the aim of removing the hardness in the water washing liquid is fulfilled;

dissolution of sodium sulfate: adopting continuous weighing and metering, sequencing batch dissolution, similar to the raw ash premixing process;

and (3) solid-liquid separation of gypsum: centrifugal solid-liquid separator or filter press

Decalcification: the sodium carbonate reacts with calcium ions in the fly ash water washing liquid to generate calcium carbonate precipitate, so that the aim of removing the hardness in the water washing liquid is fulfilled;

pumping the generated precipitate to a heavy removal process, and returning the precipitate to a water washing unit through heavy removal solid-liquid separation;

the positive displacement pump is adopted as the conveying pump, so that the probability of pipeline blockage can be effectively reduced;

overflowing the liquid phase through a sedimentation tank, adjusting the PH value, and then entering a rear end membrane separation procedure;

in addition: before decalcification, CO2 in the tail gas of the cement kiln can be introduced, and the CO2 reacts with calcium ions under an alkaline condition to generate calcium carbonate precipitate, so that the consumption of rear-end sodium carbonate is reduced, and the running cost of a system is reduced;

the reactor can adopt aeration type, the liquid can adopt an absorption tower, and the utilization rate of CO2 can be greatly improved;

the decalcification tank comprises a decalcification tank A and a decalcification tank B which are connected in parallel;

membrane separation: the ultrafiltration membrane is adopted at one section to intercept solid phase impurities in water, so that the rear end membrane is protected;

the second stage adopts nanofiltration membrane to intercept divalent ions in water, such as sulfate radical, and the concentrated solution returns to the gypsum process to combine with calcium ions in water washing liquid to generate calcium sulfate, so that the consumption of sodium sulfate is reduced, and the running cost of the system is reduced.

(5) And (3) an evaporation salt making unit:

the evaporation salt making unit has:

the sodium salt separation device comprises:

the potassium salt separation device comprises:

The evaporation process adopts a mode of falling film and forced circulation, a plurality of compressors are connected in series, the effective heat transfer temperature difference is improved, the area of a heat exchanger is reduced, and the equipment investment is saved;

potassium sodium salt separation: evaporating and crystallizing sodium chloride, and separating sodium chloride to obtain a sodium chloride product after primary salt washing;

the mother solution for separating sodium chloride adopts two sections of cooling, one section of cooling to about 80 ℃ to play a role in sedimentation, so that the sedimentation of fine sodium chloride contained in the mother solution is facilitated, the influence of sodium chloride on the quality of potassium chloride in the process of separating out potassium chloride is reduced, and the second section of cooling to 40 ℃ by adopting vacuum flash evaporation is used for separating out potassium chloride, and the separated potassium chloride product is obtained after primary salt washing of the separated potassium chloride.

Has the following advantages:

1. thoroughly recycling

2. Large treatment amount

After the washing unit is used for eluting, the chloride ions in the fly ash are reduced by about 98 percent, so that the influence of the chloride ions in the fly ash on the cement kiln is reduced, and the capacity of the fly ash for carrying out cement kiln cooperative treatment is enlarged.

3. Water washing unit

(1) The premixing tank comprises a premixing tank A and a premixing tank B which are connected in parallel; the first washing tank comprises a first washing tank A, a first washing tank B and a first washing tank C which are connected in parallel; the third washing tank comprises a third washing tank A and a third washing tank B which are connected in parallel. The third washing tank is two, and the sequencing batch operation is adopted, so that the residence time of the raw ash in the first washing tank is prolonged, and the dissolution of chloride ions in the raw ash is facilitated.

(2) The efficiency is high, a horizontal screw centrifuge is adopted for solid-liquid separation of the first and second water washing sections, and the separated filter cake is easier to break up during water washing and can be continuously operated; the three-stage water washing solid-liquid separation adopts a plate-and-frame filter press, so that the water content of wet fly ash is reduced, the content of chloride ions in the finished product ash is further reduced, and the elution efficiency of the fly ash is improved.

4. A water treatment unit, wherein the water treatment unit comprises a water treatment unit,

(1) the consumption of heavy metal medicaments is reduced, the heavy metal in water is removed by adjusting the PH, the consumption of heavy metal complexing medicaments is avoided, and the cost of the operation process is reduced.

(2) Sodium sulfate is adopted to replace sodium carbonate, the use amount of sodium carbonate is reduced, and the purpose of further reducing the energy consumption of system operation is achieved by utilizing the price difference between sodium carbonate and sodium sulfate.

(3) The solid phase separation adopts plate-frame separation, so that the solid content of the water quality of the liquid phase can be less than 1% while the energy consumption of the system operation is reduced, and the filtering pressure at the rear end is effectively reduced. The second-stage sedimentation tank adopts a sequencing batch type, and the solid phase enters a first filter tank of the washing unit.

(4) The membrane separation system can effectively reduce the system impurities from entering the evaporation salt making unit, and improve the operation efficiency of the evaporation salt making unit and the quality of product salt.

5. And (3) an evaporation salt making unit:

(1) the evaporation process adopts a mode of falling film and forced circulation, a plurality of compressors are connected in series, the effective heat transfer temperature difference is improved, the area of a heat exchanger is reduced, and the equipment investment is saved;

potassium sodium salt separation: evaporating and crystallizing sodium chloride, and separating sodium chloride product after primary salt washing to realize recycling of salt in fly ash;

after the scheme is adopted, the fly ash is treated by the cement kiln, and the residue can be directly used for cement production, so that the demand on natural resources is reduced, the damage to the environment and resources is reduced, the pollution and damage of waste to the social environment are reduced, and the cost of solid waste treatment is greatly reduced.

In the description of the present invention, it should be understood that the terms "coaxial," "bottom," "one end," "top," "middle," "another end," "upper," "one side," "top," "inner," "front," "center," "two ends," etc. indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "configured," "connected," "secured," "screwed," and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intermediaries, or in communication with each other or in interaction with each other, unless explicitly defined otherwise, the meaning of the terms described above in this application will be understood by those of ordinary skill in the art in view of the specific circumstances.

Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A cement kiln co-treatment fly ash system, comprising:

the raw ash unit stores raw ash and can send the raw ash into the washing unit;

the kiln inlet unit can collect and convey fixed substances;

the water treatment unit can treat liquid substances;

the evaporation salt making unit can recover salt in the liquid substance;

the mixer is connected with the weighing machine through a pipeline;

a premix tank;

a first wash tank;

a first solid-liquid separation device A;

a first solid-liquid separation device B;

the liquid substance of the third solid-liquid separation device A passes through the third filter tank and then enters the second washing tank through the first solid-liquid separation device A and the first solid-liquid separation device B; solid matters of the third solid-liquid separation device A enter the drying unit;

the water treatment unit has:

liquid substances in the three-stage precipitation water producing tank sequentially pass through the first-stage membrane device, the first-stage membrane water producing tank, the second-stage membrane device and the evaporation crystallization regulating tank and then enter the evaporation salt making unit;

the evaporation salt making unit has:

the sodium salt separation device comprises:

the potassium salt separation device comprises:

the solid matters separated by the potassium salt solid-liquid separation device sequentially enter a potassium salt washing device and a potassium salt second solid-liquid separation device, and the solid matters separated by the potassium salt second solid-liquid separation device are potassium chloride; liquid substances separated by the potassium salt second solid-liquid separation device enter a forced circulation heating chamber through a potassium salt mother liquor tank;

2. The cement kiln co-disposal fly ash system of claim 1, wherein said raw ash unit has a raw ash bin, a feeder, a discharger and a weighing machine connected in sequence by a pipeline, and raw ash of the raw ash unit is sent to a washing unit by the pipeline.

3. The cement kiln co-disposal fly ash system of claim 2, wherein the drying unit has:

a mixer; is connected with the third solid-liquid separation device A;

a blower for blowing hot air into the dryer;

4. A cement kiln co-disposal fly ash system as claimed in claim 3, wherein the kiln inlet unit comprises a finished product ash bin, a finished product ash inlet bin, a metering scale and a decomposing furnace which are sequentially connected through pipelines, and the materials enter the decomposing furnace through the metering scale for calcination.