CN110498628A - A kind of anhydrous gypsum preparation system - Google Patents
A kind of anhydrous gypsum preparation system Download PDFInfo
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- CN110498628A CN110498628A CN201910946721.4A CN201910946721A CN110498628A CN 110498628 A CN110498628 A CN 110498628A CN 201910946721 A CN201910946721 A CN 201910946721A CN 110498628 A CN110498628 A CN 110498628A
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- air
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- precipitator
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Classifications
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B11/00—Calcium sulfate cements
- C04B11/02—Methods and apparatus for dehydrating gypsum
- C04B11/028—Devices therefor characterised by the type of calcining devices used therefor or by the type of hemihydrate obtained
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B11/00—Calcium sulfate cements
- C04B11/05—Calcium sulfate cements obtaining anhydrite, e.g. Keene's cement
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B11/00—Calcium sulfate cements
- C04B11/26—Calcium sulfate cements strating from chemical gypsum; starting from phosphogypsum or from waste, e.g. purification products of smoke
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Processing Of Solid Wastes (AREA)
- Disintegrating Or Milling (AREA)
Abstract
The present invention relates to a kind of anhydrous gypsum preparation systems, including the first hot-blast stove, drying crusher, powder concentrator, dust-precipitator, blower, chimney, preheating dewatering module, the second hot-blast stove, cooling device, the first air-valve, the second air-valve, the first cold blast sliding valve, flue gas purification device, third air-valve and the second cold blast sliding valve;First hot-blast stove, drying crusher, powder concentrator, dust-precipitator, blower and chimney are sequentially connected in gas circuit;Drying crusher, powder concentrator, dust-precipitator, preheating dewatering module and cooling device are sequentially connected in material tube;The present invention realizes stage-by-stage heat exchange using suspension calcining device, to thoroughly remove the moisture in ardealite, II type anhydrous gypsum of high quality is made, and has function of temperature control, it can prevent hot wind from burning out equipment in fracture or other unusual service conditions, eliminate security risk.
Description
Technical field
The present invention relates to a kind of anhydrous gypsum preparation systems.
Background technique
Ardealite is a kind of industrial by-products generated when preparing phosphoric acid, and the main mineral constituent in ardealite is stone
Cream, based on calcium sulphate dihydrate, followed by quartzy and dressing agent residue;Ardealite arbitrarily stacks the acid-base property that can destroy soil,
Water-soluble phosphorus and fluorine flow into rivers with rainwater also can serious polluted-water quality, it is therefore necessary to could stack after being handled;
Since ardealite contains, water content is higher, also contains certain impurity, although main component is identical as the natural gypsum, also not
The energy direct image natural gypsum is equally handled.
Dihydrate gypsum dry powder, Ban Shui can be made by cleaning, drying the technologies such as outer water, decomposition and crystallization water in ardealite
Gypsum and anhydrous gypsum, to be used for the field of building materials;According to process conditions difference, the product and crystal form of preparation are also different,
Dihydrate gypsum, which is heated to 135 DEG C to 200 DEG C, with high pressure or the mode of boiling can be made alpha semi-hydrated gypsum, alpha semi-hydrated gypsum
Intensity is higher, but complex process, and control condition is more stringent, and production method is discontinuous production, it is difficult to large industrialized production;
According to calcining manners, beta-type semi-hydrated gypsum can be made by being heated to 160 DEG C to 200 DEG C, beta-type semi-hydrated gypsum have heat preservation, lightweight,
Solidification is fast, shrinks the advantages that small, but the intensity of semi-hydrated gypsum and water resistance be not good enough;According to calcining manners, and will calcining temperature
Degree control gypsum under 360 DEG C~1180 DEG C, condition of normal pressure can be converted into II type anhydrous gypsum, and II type anhydrous gypsum has good
Water resistance and intensity, intensity is also higher than alpha semi-hydrated gypsum.
It is current ardealite resource utilization that ardealite is prepared into II type anhydrous gypsum by way of calcined dehydration
A kind of preferable mode, existing anhydrous gypsum preparation system handle ardealite, phosphorus stone mostly by the way of concentrating calcining
Moisture in cream is unable to fully thoroughly remove, and it is lower that product quality is made;And lack function of temperature control, cause calcining to generate
Hot wind is easy to burn out equipment in fracture or other unusual service conditions, and there are security risks, need further improvement.
Summary of the invention
In view of the above-mentioned state of the art, technical problem to be solved by the present invention lies in provide it is a kind of using suspend forge
Device is burnt to realize stage-by-stage heat exchange so that the moisture in ardealite thoroughly to be removed to and be improved the quality of II type anhydrous gypsum, and is had
The anhydrous gypsum preparation system of security risk is eliminated for function of temperature control.
The technical scheme of the invention to solve the technical problem is: a kind of anhydrous gypsum preparation system, including the
One hot-blast stove, drying crusher, powder concentrator, dust-precipitator, blower, chimney, preheating dewatering module, the second hot-blast stove, cooling device,
First air-valve, the second air-valve, the first cold blast sliding valve, flue gas purification device, third air-valve and the second cold blast sliding valve, which is characterized in that institute
The first hot-blast stove, drying crusher, powder concentrator, dust-precipitator, blower and chimney is stated to be sequentially connected in gas circuit;The drying is broken
Machine, powder concentrator, dust-precipitator, preheating dewatering module and cooling device are sequentially connected in material tube;Second hot-blast stove and preheating
The air inlet of dewatering module is connected, and the air outlet of the preheating dewatering module is connected with the blast pipe of drying crusher;Described
The first air-valve, the air outlet of the preheating dewatering module and the blast pipe of drying crusher are provided on the discharge pipe of one hot-blast stove
Between be provided with the second air-valve, be additionally provided with the first cold blast sliding valve on the discharge pipe of first hot-blast stove;The dust-precipitator and wind
It is additionally provided with flue gas purification device between machine, is provided between the discharge pipe of the preheating dewatering module and the blast pipe of dust-precipitator
Third air-valve is provided with the second cold blast sliding valve between the preheating dewatering module and the second hot-blast stove.
Preferably, the preheating dewatering module includes multiple cyclone preheating devices being serially connected.
It preferably, further include conveyer belt, the conveyer belt is arranged in below the slag-drip opening of dust-precipitator.
Compared with the prior art, the advantages of the present invention are as follows: the present invention realizes stage-by-stage heat exchange using suspension calcining device,
To thoroughly remove the moisture in ardealite, II type anhydrous gypsum of high quality is made, and have function of temperature control, it can be disconnected
It prevents hot wind from burning out equipment when material or other unusual service conditions, eliminates security risk.
Detailed description of the invention
Fig. 1 is structure principle chart of the invention.
Specific embodiment
As shown in Figure 1, a kind of anhydrous gypsum preparation system, including the first hot-blast stove 1, drying crusher 2, powder concentrator 3, receipts
Dirt device 4, blower 5, chimney 6, preheating dewatering module 7, the second hot-blast stove 8, cooling device 9, the first air-valve 10, the second air-valve 11,
First cold blast sliding valve 12, flue gas purification device 13, third air-valve 14, the second cold blast sliding valve 15 and conveyer belt 17;First hot-blast stove 1 dries
Dry crusher 2, powder concentrator 3, dust-precipitator 4, blower 5 and chimney 6 are sequentially connected in gas circuit;Drying crusher 2, is received powder concentrator 3
Dirt device 4, preheating dewatering module 7 and cooling device 9 are sequentially connected in material tube;Second hot-blast stove 8 and preheating dewatering module 7 into
Air port is connected, and the air outlet of preheating dewatering module 7 is connected with the blast pipe of drying crusher 2;It includes multiple for preheating dewatering module 7
The cyclone preheating device 16 being serially connected;Conveyer belt 17 is arranged in below the slag-drip opening of dust-precipitator 4;The outlet air of first hot-blast stove 1
The first air-valve 10 is additionally provided on pipe, the first air-valve 10 is used to control and adjust the flue gas of the first hot-blast stove 1;In pre- heat dehydration mould
The second air-valve 11 is additionally provided between the air outlet of block 7 and the blast pipe of drying crusher 2, the second air-valve 11 is used to control and adjust
Section preheating dewatering module 7 is delivered to the air quantity in drying crusher 2, real by the regulation of the first air-valve 10 and the second air-valve 11
The ratio of existing two strands of exhaust gas is moderate, to facilitate adjusting to select powder air quantity, strip concentration and drying, dehydrating effect;First hot-blast stove 1
The first cold blast sliding valve 12 is additionally provided on discharge pipe, for controlling and adjusting the air quantity and temperature of 1 exiting flue gas of the first hot-blast stove, with
Drying crusher 2 and 3 required airflows of powder concentrator are better adapted to, and meets air-flow strip and selects powder requirement;At the same time it can also make
The flue-gas temperature of the first hot-blast stove 1 is unlikely to excessively high out, when there is the unusual service condition of fracture, by opening the first cold blast sliding valve 12
To mix cold wind, to prevent excessively high flue-gas temperature from burning out drying crusher 2 and follow-up equipment, dust-precipitator 4 and blower 5 it
Between be additionally provided with flue gas purification device 13, for removing the harmful substances such as sulfureous in flue gas, phosphorus, referred to the discharge met environmental requirements
Mark;It preheats and is additionally provided with third air-valve 14 between the discharge pipe of dewatering module 7 and the blast pipe of dust-precipitator 4, for controlling and adjusting
The intake volume for saving dust-precipitator 4, can also combine adjusting with the second air-valve 11, be discharged from preheating dewatering module 7 to adjust
To the air force of drying crusher 2 and 4 two-way flue gas of dust-precipitator;It is also set up between preheating dewatering module 7 and the second hot-blast stove 8
There is the second cold blast sliding valve 15, for adjusting into preheating in dewatering module 7 to the hot blast temperature for removing phosphogypsum crystal water, makes it
It is unlikely to excessively high, when there is the unusual service condition of fracture, the temperature for being unlikely to excessively high will preheat dewatering module 7 and follow-up equipment is burnt
It is bad, play the role of emergency protection.
Process flow: the first hot-blast stove 1 provides fuel flue gas to drying crusher 2, air inlet of the flue gas from drying crusher 2
Mouth enters in drying crusher 2, and ardealite raw material enters in drying crusher 2 from the feed inlet of drying crusher 2, is drying
It completes to break up in dry crusher 2 and be dried the step of removing with outer water, the powdery ardealite after breaing up is oven-dried hot wind band and is selected in powder
To carry out particle classifying in machine 3, coarse powder is returned in drying crusher 2, and fine powder is brought into dust-precipitator 4 by air-flow, and then is realized dry
The collection of powdery ardealite (or part semi-hydrated gypsum), the exhaust gas generated in dust-precipitator 4 are discharged into atmosphere via blower 5 and chimney 6;
If the temperature in drying crusher 2 is higher (>=150 DEG C), most of half water stone can be made in the material being discharged from drying crusher 2
Cream can also contain part dry powder-shaped dihydrate gypsum since drying time is shorter;The dry powder phosphogypsum of drying is sent into pre- heat dehydration
The removing of the crystallization water is carried out in module 7, the second hot-blast stove 8 provides hot fume to preheating dewatering module 7, and then by dry powder-shaped phosphorus stone
The crystallization water of cream is taken off, and powdered anhydrous gypsum is prepared into, and then send to cooling down in cooling device 9;Material is de- along preheating
16 material of multiple cyclone preheating devices in water module 7 is run from top to bottom, and the hot wind that the second hot-blast stove 8 generates is along multiple whirlwind
Preheating device 16 is run from bottom to top, and hot wind and material carry out stage-by-stage heat exchange, completes crystallization water removing in heat transfer process with this,
Wherein, the control of most next stage hot wind to realize that remaining half of the crystallization water of ardealite is totally removed, and is prepared at 400 DEG C or more
At II type anhydrous gypsum;Discharge pipe in preheating dewatering module 7 is divided into two-way, connects the blast pipe of drying crusher 2 all the way, with
Enter in drying crusher 2 together from the hot fume of the first hot-blast stove 1, and then high moisture content ardealite is dried, is removed outside
Water;Another way connects the blast pipe of dust-precipitator 4, the preheated dewatering module 7 of ardealite remove the hot fume after the crystallization water directly with baking
The exhaust gas merger of the discharge of the powder concentrator 3 of dry crushing system enters in dust-precipitator 4 together, converges exhaust gas and passes through dust-precipitator 4 for powder
Atmosphere is discharged by blower 5 and chimney 6 after dirt filtering;The impurity absorbed in dust-precipitator 4 can be periodically discharged by conveyer belt 17;
When ardealite moisture content is larger, third air-valve 14 can be closed, hot fume fully enters in drying crusher 2, to reduce
The hot wind heat of one hot-blast stove 1, and then reduce system energy consumption;When ardealite moisture content is smaller, the first air-valve 10 can be cut off, is dried
Drying hot wind in dry crusher 2 all is from preheating dewatering module 7, so that exhaust gas and preheating that drying crusher 2 generates are de-
The gas circuit of water module 7 is connected;It, can when preheating the exhaust gas temperature of dewatering module 7 lower than the exhaust gas temperature that drying crusher 2 is discharged
Third air-valve 14 is closed and opens to close the second air-valve 11, the exhaust gas that preheating dewatering module 7 generates fully enters dust-precipitator 4
Interior, the gas circuit of the exhaust gas that drying crusher 2 generates and preheating dewatering module 7 is parallel with one another.
Ardealite is prepared into one kind that II type anhydrous gypsum is ardealite resource utilization by way of calcined dehydration
Preferable mode, existing anhydrous gypsum preparation system handles ardealite mostly by the way of concentrating calcining, in ardealite
Moisture be unable to fully thoroughly remove, be made product quality it is lower;And lack function of temperature control, the hot wind for causing calcining to generate
It is easy to burn out equipment, there are security risks in fracture or other unusual service conditions;The present invention is using suspension calcining device come real
Existing stage-by-stage heat exchange II type anhydrous gypsum of high quality is made, and has temperature control to thoroughly removing the moisture in ardealite
Function can prevent hot wind from burning out equipment, eliminate security risk in fracture or other unusual service conditions.
Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations;Although
Present invention has been described in detail with reference to the aforementioned embodiments, it will be understood by those of skill in the art that it still can be right
Technical solution documented by foregoing embodiments is modified, or is replaced on an equal basis to part of technical characteristic;And this
It modifies or replaces, the spirit and model of technical solution of various embodiments of the present invention that it does not separate the essence of the corresponding technical solution
It encloses.
Claims (3)
1. a kind of anhydrous gypsum preparation system, including the first hot-blast stove, drying crusher, powder concentrator, dust-precipitator, blower, chimney,
Preheat dewatering module, the second hot-blast stove, cooling device, the first air-valve, the second air-valve, the first cold blast sliding valve, flue gas purification device, the
Three air-valves and the second cold blast sliding valve, which is characterized in that first hot-blast stove, drying crusher, powder concentrator, dust-precipitator, blower and
Chimney is sequentially connected in gas circuit;The drying crusher, powder concentrator, dust-precipitator, preheating dewatering module and cooling device are being expected
Road is sequentially connected;Second hot-blast stove is connected with the air inlet of preheating dewatering module, the outlet air of the preheating dewatering module
Mouth is connected with the blast pipe of drying crusher;The first air-valve is provided on the discharge pipe of first hot-blast stove, the preheating is de-
The second air-valve is provided between the air outlet of water module and the blast pipe of drying crusher, on the discharge pipe of first hot-blast stove
It is additionally provided with the first cold blast sliding valve;Flue gas purification device, the preheating dewatering module are additionally provided between the dust-precipitator and blower
Discharge pipe and dust-precipitator blast pipe between be provided with third air-valve, set between the preheating dewatering module and the second hot-blast stove
It is equipped with the second cold blast sliding valve.
2. a kind of anhydrous gypsum preparation system according to claim 1, which is characterized in that the preheating dewatering module includes
Multiple cyclone preheating devices being serially connected.
3. a kind of anhydrous gypsum preparation system according to claim 1, which is characterized in that it further include conveyer belt, it is described defeated
Band is sent to be arranged in below the slag-drip opening of dust-precipitator.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910946721.4A CN110498628A (en) | 2019-10-07 | 2019-10-07 | A kind of anhydrous gypsum preparation system |
PCT/CN2020/088942 WO2021068499A1 (en) | 2019-10-07 | 2020-05-07 | Anhydrite preparation system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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CN201910946721.4A CN110498628A (en) | 2019-10-07 | 2019-10-07 | A kind of anhydrous gypsum preparation system |
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CN110498628A true CN110498628A (en) | 2019-11-26 |
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CN201910946721.4A Withdrawn CN110498628A (en) | 2019-10-07 | 2019-10-07 | A kind of anhydrous gypsum preparation system |
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CN (1) | CN110498628A (en) |
WO (1) | WO2021068499A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111362604A (en) * | 2020-03-16 | 2020-07-03 | 江苏安必信环保设备有限公司 | II type anhydrous gypsum roasting process |
WO2021068499A1 (en) * | 2019-10-07 | 2021-04-15 | 南京凯盛国际工程有限公司 | Anhydrite preparation system |
CN116003006A (en) * | 2023-01-06 | 2023-04-25 | 武汉建筑材料工业设计研究院有限公司 | Device and method for preparing II-type anhydrous gypsum from suspension phosphogypsum |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116354631A (en) * | 2023-04-03 | 2023-06-30 | 宁夏博得石膏研究院(有限公司) | Efficient hot air mixing heat exchange type one-step gypsum calcination system and process |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1331738C (en) * | 2000-09-01 | 2007-08-15 | 山东鲁北企业集团总公司 | Process and equipment for decomposing gypsum |
CN100434380C (en) * | 2006-09-06 | 2008-11-19 | 山东天力干燥设备有限公司 | Technique for airflow drying, and calcining desulfurized gypsum |
CN101955166B (en) * | 2009-07-20 | 2013-07-31 | 瓮福(集团)有限责任公司 | Method for decomposing semi-hydrated phosphogypsum |
CN103663388B (en) * | 2013-12-06 | 2015-04-22 | 云南创兴建材新技术有限公司 | Method and reactor for preparing high concentration SO2 flue gas by using phosphogypsum through CaS |
CN103936313B (en) * | 2014-05-08 | 2015-09-30 | 瓮福(集团)有限责任公司 | The technique of building gypsum plaster prepared by a kind of phosphogypsum |
CN110128040B (en) * | 2019-06-27 | 2023-10-20 | 长沙紫宸科技开发有限公司 | Equipment system for preparing anhydrite powder by large-scale phosphogypsum digestion |
CN110498628A (en) * | 2019-10-07 | 2019-11-26 | 南京凯盛国际工程有限公司 | A kind of anhydrous gypsum preparation system |
-
2019
- 2019-10-07 CN CN201910946721.4A patent/CN110498628A/en not_active Withdrawn
-
2020
- 2020-05-07 WO PCT/CN2020/088942 patent/WO2021068499A1/en active Application Filing
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2021068499A1 (en) * | 2019-10-07 | 2021-04-15 | 南京凯盛国际工程有限公司 | Anhydrite preparation system |
CN111362604A (en) * | 2020-03-16 | 2020-07-03 | 江苏安必信环保设备有限公司 | II type anhydrous gypsum roasting process |
CN111362604B (en) * | 2020-03-16 | 2022-05-03 | 江苏安必信环保设备有限公司 | II type anhydrous gypsum roasting process |
CN116003006A (en) * | 2023-01-06 | 2023-04-25 | 武汉建筑材料工业设计研究院有限公司 | Device and method for preparing II-type anhydrous gypsum from suspension phosphogypsum |
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Application publication date: 20191126 |