CN109231856A - A kind of preparation method for calcining carbide slag and its application in bittern purifying process - Google Patents
A kind of preparation method for calcining carbide slag and its application in bittern purifying process Download PDFInfo
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- CN109231856A CN109231856A CN201811468160.3A CN201811468160A CN109231856A CN 109231856 A CN109231856 A CN 109231856A CN 201811468160 A CN201811468160 A CN 201811468160A CN 109231856 A CN109231856 A CN 109231856A
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- carbide slag
- calcining
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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
- C04B2/00—Lime, magnesia or dolomite
- C04B2/005—Lime, magnesia or dolomite obtained from an industrial by-product
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/16—Purification
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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
- C04B2/00—Lime, magnesia or dolomite
- C04B2/10—Preheating, burning calcining or cooling
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
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- Inorganic Chemistry (AREA)
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- Thermal Sciences (AREA)
- Processing Of Solid Wastes (AREA)
Abstract
The invention discloses a kind of preparation method for calcining carbide slag and its applications in bittern purifying process, and dry carbide slag is crushed, kiln is delivered to, is calcined at a certain temperature, obtain calcining carbide slag.Carbide slag will be calcined and charging slaking apparatus is added in water, the ratio and temperature of carbide slag and water is controlled, digest and stand after a certain period of time, be then sufficiently stirred, then digest and complete after a period of time；Slag is filtered out through square hole screen, filtering carbide slag refining is aged, carbide slag refining is again through in delivery pump injection storage pool after ageing, and is pumped into the fresh water in storage pool that be connected to halogen well molten intracavitary simultaneously；Molten intracavitary in halogen well, carbide slag refining is completed first class purification with soluble impurity and is reacted；The brine obtained after first class purification is reacted is pumped into second order reaction bucket, opens inwards into flue gas, is completed secondary purification and is reacted, after separation of solid and liquid, filtrate Jing Lusong salt manufacturing factory.The beneficial effects of the invention are as follows cheap replacing carbide slag with lime is used, production run cost has not only been reduced, but also has made the efficient high level resource utilization of large solid waste carbide slag, economy, environmental and social benefits are significant.
Description
Technical field
The present invention relates to a kind of preparation method for calcining carbide slag and its applications in bittern purifying process.
Background technique
Carbide slag is the waste residue that industrial production acetylene gas, polyvinyl chloride, polyvinyl alcohol etc. generate after calcium carbide hydrolyzes in the process.
Since carbide slag is the industrial residue with processing, for accumulative volume of cargo in storage up to 1.3 hundred million t, domestic production producer is most of will be electric at present
Rock ballast is stacked or is filled on the spot.With the continuous expansion of the chemical products scale such as domestic PVC, PVA, carbide slag data volume will be more next
It is more.Not only occupy valuable land resource, but also environment and human health, it has also become a social big public hazards.
The main component of carbide slag is Ca (OH)2> 90%, and Ca (OH)2Thermal decomposition starting temperature be about 360 DEG C, and
CaCO3Thermal decomposition starting temperature be about 600 DEG C, therefore with carbide slag decompose generate CaO energy consumption compare CaCO3Want much lower,
Therefore, it is used to substitute lime after carbide slag being calcined, can be used for bittern purifying technique, save lime cost.
The purpose of bittern purifying is exactly the impurity removed in brine, obtains qualified purification brine.Purify Galuber's salt type brine
A kind of most common method is exactly " lime-flue gas " method, and technological principle is divided into two steps: the first step, is first added in brine
Lime generates OH-Remove the Mg in brine2+Be used for second step；
CaO+H2O= Ca(OH)2
Ca(OH)2+MgSO4= Mg (OH)2↓ + CaSO4
Ca(OH)2+Na2SO4=2NaOH + CaSO4
Second step is passed through flue gas in the clarified solution after the first step, utilizes the CO in flue gas2And OH-Reaction generates Na2CO3, then
With Ca2+Reaction generates CaCO3Precipitating removes Ca to reach2+Purpose；
CO2+2NaOH=Na2CO3+H2O
Na2CO3+ CaSO4=CaCO3↓+ Na2SO4
Wherein, lime role is that enough OH are generated in brine-, using calcining replacing carbide slag with lime, cost is excellent
Gesture is obvious, and carbide slag realizes that waste residue recycles, and achievees the purpose that environmental protection.
Summary of the invention
The purpose of the present invention is to provide a kind of calcining preparation method of carbide slag and its answering in bittern purifying process
With solving the recycling of existing carbide slag waste material, achieve the purpose that environmental protection.
In order to realize above-mentioned purpose of the invention, the technical scheme adopted by the invention is that:
Dry carbide slag is crushed, 200 ~ 400 powder materials are obtained, kiln is delivered to, is calcined at a certain temperature, forged
Baking carbide residue.
In a preferred embodiment of the invention, calcination temperature is 500 ~ 600 DEG C.
It is a kind of calcine carbide slag purposes be in adopting halogen production process, be used for Galuber's salt type brine cleaning procedure, specifically press
It is carried out according to following steps:
Step 1: digestion；Charging slaking apparatus is added in a certain proportion of calcining carbide slag and water, digests, disappears at a certain temperature
Certain time is stood after having changed, is then sufficiently stirred, then digests and completes after 1 ~ 5 h；
Step 2: sieving；Slag is filtered out through square hole screen, obtains certain density carbide slag slurry；
Step 3: refining ageing；After sieving, the ageing of certain time is carried out to carbide slag refining obtained；
Step 4: first class purification；Through in delivery pump injection storage pool, and it is pumped into the fresh water in storage pool that be connected to halogen well molten simultaneously
It is intracavitary；Molten intracavitary in halogen well, during water-soluble, soluble impurity also dissolves ore bed simultaneously, into solution, soluble impurity with
Carbide slag or carbide slag, lime mixture in Ca (OH)2It chemically reacts, generates slightly solubility substance Mg (OH)2, and
The NaOH that concentration is 0.5 ~ 1.5 g/L, the OH in brine are obtained in brine-The concentration of ion is 0.1 ~ 0.7 g/L, completes level-one
Purification reaction.Wherein, the chemical equation of first class purification reaction are as follows:
CaO+H2O= Ca(OH)2
Ca(OH)2+MgSO4= Mg (OH)2↓ + CaSO4
Ca(OH)2+Na2SO4=2NaOH + CaSO4
Step 5: secondary purification；The brine obtained after first class purification is reacted is pumped into second order reaction bucket, opens inwards into flue gas, complete
It is reacted at second level bittern purifying.The chemical equation of secondary purification reaction are as follows:
CO2+2NaOH=Na2CO3+H2O
Na2CO3+ CaSO4=CaCO3↓+ Na2SO4
After separation of solid and liquid, filtrate Jing Lusong salt manufacturing factory.
In a preferred embodiment of the invention, the ratio of the calcining carbide slag and water in step 1 is 1:6 ~ 1:14.
In a preferred embodiment of the invention, the digestion temperature in step 1 is controlled at 30 ~ 80 DEG C.
In a preferred embodiment of the invention, time of repose is 1 ~ 5 h after the digestion in step 1.
In a preferred embodiment of the invention, square hole screen used is 300 ~ 500 mesh in step 2.
In a preferred embodiment of the invention, carbide slag refining digestion time is 1 ~ 24 h in step 3.
The present invention has the advantages that the present invention use cheap replacing carbide slag with lime, both reduced production run at
This, and make the efficient high level resource utilization of large solid waste carbide slag, economy, environmental and social benefits are significant.
Detailed description of the invention
Fig. 1 is a kind of calcining carbide slag process flow diagram in bittern purifying process of the present invention.
Specific embodiment
By following specific embodiments, invention is further described in detail.
Embodiment 1:
A kind of preparation method of the calcining carbide slag of the present embodiment and its in bittern purifying process application the following steps are included:
(1) dry carbide slag is crushed, obtains 200 ~ 400 powder materials, is delivered to kiln, calcined, obtained at 500 ~ 600 DEG C
To calcining carbide slag.
(2) charging slaking apparatus is added in calcining carbide slag and water, controls the ratio of carbide slag and water for 1:6 between, it is warm
Degree control stands 2 h after having digested, is then sufficiently stirred at 30 DEG C, 3 h of digestion time, then digests and complete after 1 ~ 5 h；Through
The filtering of 400 mesh square hole screens is slagged tap, and carries out 10 h ageings to filtering carbide slag refining, carbide slag refining is infused through delivery pump again after ageing
Enter in storage pool, and is pumped into the fresh water in storage pool that be connected to halogen well molten intracavitary simultaneously；
(3) molten intracavitary in halogen well, during water-soluble, soluble impurity also dissolves ore bed simultaneously, into solution, soluble impurity
With carbide slag or carbide slag, lime mixture in Ca (OH)2It chemically reacts, generates slightly solubility substance Mg (OH)2, and
The NaOH that concentration is 0.6 ~ 1.3 g/L, the OH in brine are obtained in brine-The concentration of ion is 0.2 ~ 0.6g/L, completes one
Grade purification reaction.Wherein, the chemical equation of first class purification reaction are as follows:
CaO+H2O= Ca(OH)2
Ca(OH)2+MgSO4= Mg (OH)2↓ + CaSO4
Ca(OH)2+Na2SO4=2NaOH + CaSO4
(4) brine obtained after reacting first class purification is pumped into second order reaction bucket, opens inwards into flue gas, and it is net to complete second level brine
Change reaction.The chemical equation of secondary purification reaction are as follows:
CO2+2NaOH=Na2CO3+H2O
Na2CO3+ CaSO4=CaCO3↓+ Na2SO4
(5) it after secondary purification reaction, is separated by solid-liquid separation, filtrate Jing Lusong salt manufacturing factory.
Embodiment 2:
The bittern purifying technique of the present embodiment specifically includes the following steps:
(1) dry carbide slag is crushed, obtains 200 ~ 400 powder materials, is delivered to kiln, calcined, obtained at 500 ~ 600 DEG C
To calcining carbide slag.
(2) charging slaking apparatus is added in calcining carbide slag and water, controls the ratio of carbide slag and water for 1:10 between, it is warm
Degree control stands 3 h after having digested, is then sufficiently stirred at 80 DEG C, 4 h of digestion time, then digests and complete after 5 h；Through
The filtering of 500 mesh square hole screens is slagged tap, and carries out 20 h ageings to filtering carbide slag refining, carbide slag refining is infused through delivery pump again after ageing
Enter in storage pool, and is pumped into the fresh water in storage pool that be connected to halogen well molten intracavitary simultaneously；
(3) molten intracavitary in halogen well, during water-soluble, soluble impurity also dissolves ore bed simultaneously, into solution, soluble impurity
With carbide slag or carbide slag, lime mixture in Ca (OH)2It chemically reacts, generates slightly solubility substance Mg (OH)2, and
The NaOH that concentration is 0.5 ~ 1.5 g/L, the OH in brine are obtained in brine-The concentration of ion is 0.1 ~ 0.7g/L, completes one
Grade purification reaction.Wherein, the chemical equation of first class purification reaction are as follows:
CaO+H2O= Ca(OH)2
Ca(OH)2+MgSO4= Mg (OH)2↓ + CaSO4
Ca(OH)2+Na2SO4=2NaOH + CaSO4
(4) brine obtained after reacting first class purification is pumped into second order reaction bucket, opens inwards into flue gas, and it is net to complete second level brine
Change reaction.The chemical equation of secondary purification reaction are as follows:
CO2+2NaOH=Na2CO3+H2O
Na2CO3+ CaSO4=CaCO3↓+ Na2SO4
(5) it after secondary purification reaction, is separated by solid-liquid separation, filtrate Jing Lusong salt manufacturing factory.
Embodiment 3:
The bittern purifying technique of the present embodiment specifically includes the following steps:
(1) dry carbide slag is crushed, obtains 200 ~ 400 powder materials, is delivered to kiln, calcined, obtained at 500 ~ 600 DEG C
To calcining carbide slag.
(2) charging slaking apparatus is added in calcining carbide slag and water, control carbide slag and water ratio be 1:6 ~ 1:14 it
Between, temperature is controlled at 30 ~ 80 DEG C, 1 ~ 5 h of digestion time, is stood 1 ~ 3 h after having digested, is then sufficiently stirred, then through 1 ~ 5 h
Digestion is completed afterwards；It slags tap through the filtering of 300 ~ 500 mesh square hole screens, 1 ~ 24 h ageing is carried out to filtering carbide slag refining, it is electric after ageing
Rock ballast refining is pumped into the fresh water in storage pool that be connected to halogen well molten intracavitary again through in delivery pump injection storage pool simultaneously；
(3) molten intracavitary in halogen well, during water-soluble, soluble impurity also dissolves ore bed simultaneously, into solution, soluble impurity
With carbide slag or carbide slag, lime mixture in Ca (OH)2It chemically reacts, generates slightly solubility substance Mg (OH)2, and
The NaOH that concentration is 0.55 ~ 1.45 g/L, the OH in brine are obtained in brine-The concentration of ion is 0.12 ~ 0.65g/L, complete
It is reacted at first class purification.Wherein, the chemical equation of first class purification reaction are as follows:
CaO+H2O= Ca(OH)2
Ca(OH)2+MgSO4= Mg (OH)2↓ + CaSO4
Ca(OH)2+Na2SO4=2NaOH + CaSO4
(4) brine obtained after reacting first class purification is pumped into second order reaction bucket, opens inwards into flue gas, and it is net to complete second level brine
Change reaction.The chemical equation of secondary purification reaction are as follows:
CO2+2NaOH=Na2CO3+H2O
Na2CO3+ CaSO4=CaCO3↓+ Na2SO4
(5) it after secondary purification reaction, is separated by solid-liquid separation, filtrate Jing Lusong salt manufacturing factory.
The above is only a preferred embodiment of the present invention, is not intended to restrict the invention, it is clear that those skilled in the art can
To carry out various changes, modification without departing from the spirit and scope of the present invention to the present invention.If to these modifications of the invention
Within the scope of the claims of the present invention and its equivalent technology with modification, it all belongs to the scope of protection of the present invention.
Claims (8)
1. a kind of preparation method for calcining carbide slag: dry carbide slag is crushed, 200 ~ 400 powder materials is obtained, is delivered to kiln,
It is calcined at a certain temperature, obtains calcining carbide slag.
2. a kind of preparation method for calcining carbide slag described in claim 1, which is characterized in that calcination temperature is 500 ~ 600 DEG C.
3. it is a kind of calcine carbide slag purposes be in adopting halogen production process, be used for Galuber's salt type brine cleaning procedure, specifically according to
Following steps carry out:
Step 1: digestion；Charging slaking apparatus is added in a certain proportion of calcining carbide slag and water, digests, disappears at a certain temperature
Certain time is stood after having changed, is then sufficiently stirred, then digests and completes after 1 ~ 5 h；
Step 2: sieving；Slag is filtered out through square hole screen, obtains certain density carbide slag slurry；
Step 3: refining ageing；After sieving, the ageing of certain time is carried out to carbide slag refining obtained；
Step 4: first class purification；Through in delivery pump injection storage pool, and it is pumped into the fresh water in storage pool that be connected to halogen well molten simultaneously
It is intracavitary；Molten intracavitary in halogen well, carbide slag refining is completed first class purification with soluble impurity and is reacted；
Step 5: secondary purification；The brine obtained after first class purification is reacted is pumped into second order reaction bucket, opens inwards into flue gas, complete
It is reacted at secondary purification, after separation of solid and liquid, filtrate Jing Lusong salt manufacturing factory.
4. a kind of purposes for calcining carbide slag as claimed in claim 3, which is characterized in that calcining carbide slag and water in step 1
Ratio be 1:6 ~ 1:14.
5. a kind of purposes for calcining carbide slag as claimed in claim 3, which is characterized in that the digestion temperature control in step 1 exists
30~80 ℃。
6. a kind of purposes for calcining carbide slag as claimed in claim 3, which is characterized in that time of repose after the digestion in step 1
For 1 ~ 5 h.
7. a kind of purposes for calcining carbide slag as claimed in claim 3, which is characterized in that in step 2 square hole screen used be 300 ~
500 mesh.
8. a kind of purposes for calcining carbide slag as claimed in claim 3, which is characterized in that when carbide slag refining is aged in step 3
Between be 1 ~ 24 h.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811468160.3A CN109231856A (en) | 2018-12-03 | 2018-12-03 | A kind of preparation method for calcining carbide slag and its application in bittern purifying process |
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| CN201811468160.3A CN109231856A (en) | 2018-12-03 | 2018-12-03 | A kind of preparation method for calcining carbide slag and its application in bittern purifying process |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110745844A (en) * | 2019-11-29 | 2020-02-04 | 江西晶昊盐化有限公司 | Method for purifying brine by using ammonia-soda waste residue and waste liquid mixed liquor and flue gas |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1035097A (en) * | 1988-02-08 | 1989-08-30 | 重庆建筑工程学院 | Use production of calcium oxide of high activity from calcium carbide residue |
| JPH06157083A (en) * | 1992-11-18 | 1994-06-03 | Osaka Koukai Kk | Production of powdery quick lime for injection in metal refining and production of lime-based heat insulating material for floatable in surface of smelted metal and refractory for metal refining furnace |
| CN101514027A (en) * | 2009-03-09 | 2009-08-26 | 王红 | Manufacturing technique for preparing calcium oxide by using acetylene sludge |
| CN104477940A (en) * | 2014-12-02 | 2015-04-01 | 湖南省湘衡盐化有限责任公司 | Brine purification technique by carbide slag/lime-flue gas process |
| CN108483477A (en) * | 2018-07-03 | 2018-09-04 | 中国科学院过程工程研究所 | A method of preparing active calcium oxide using carbide slag |
-
2018
- 2018-12-03 CN CN201811468160.3A patent/CN109231856A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1035097A (en) * | 1988-02-08 | 1989-08-30 | 重庆建筑工程学院 | Use production of calcium oxide of high activity from calcium carbide residue |
| JPH06157083A (en) * | 1992-11-18 | 1994-06-03 | Osaka Koukai Kk | Production of powdery quick lime for injection in metal refining and production of lime-based heat insulating material for floatable in surface of smelted metal and refractory for metal refining furnace |
| CN101514027A (en) * | 2009-03-09 | 2009-08-26 | 王红 | Manufacturing technique for preparing calcium oxide by using acetylene sludge |
| CN104477940A (en) * | 2014-12-02 | 2015-04-01 | 湖南省湘衡盐化有限责任公司 | Brine purification technique by carbide slag/lime-flue gas process |
| CN108483477A (en) * | 2018-07-03 | 2018-09-04 | 中国科学院过程工程研究所 | A method of preparing active calcium oxide using carbide slag |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110745844A (en) * | 2019-11-29 | 2020-02-04 | 江西晶昊盐化有限公司 | Method for purifying brine by using ammonia-soda waste residue and waste liquid mixed liquor and flue gas |
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