CN103979811A - Method for converting flue gas desulfurized gypsum into high-strength alpha-type hemihydrate gypsum - Google Patents
Method for converting flue gas desulfurized gypsum into high-strength alpha-type hemihydrate gypsum Download PDFInfo
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- CN103979811A CN103979811A CN201410186215.7A CN201410186215A CN103979811A CN 103979811 A CN103979811 A CN 103979811A CN 201410186215 A CN201410186215 A CN 201410186215A CN 103979811 A CN103979811 A CN 103979811A
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Abstract
The invention discloses a method for converting flue gas desulfurized gypsum into high-strength alpha-type hemihydrate gypsum. The method comprises the following steps: mixing flue gas desulfurized gypsum with water according to a solid-liquid mass ratio of 1: 4-10 and placing an obtained mixture in a high pressure reactor; adding a crystallization additive magnesium chloride hexahydrate and a crystal habit modifier succinic acid so as to finish slurry mixing; and carrying out heat preservation at a temperature of 110 to 120 for 2 to 3 h to finish crystal transformation and carrying out filtering and washing so as to prepare high-strength alpha-type hemihydrate gypsum. The method further simplifies preparation technology and reduces cost; the prepared high-strength alpha-type hemihydrate gypsum has breaking strength of 14.7 MPa and compressive strength of 46.5 MPa. Through implementation of the method provided by the invention, exploitation of natural gypsum ore is reduced, the waste is turned into the valuable, and the environment is protected.
Description
Technical field
The invention belongs to material science, relate in particular to a kind of employing hydrothermal method and take desulfurized gesso of flue gas as main raw material, prepare the method for high strength alpha semi-hydrated gypsum.
Background technology
In recent years, along with the sustained and rapid development of national economy, the generated energy of China increases year by year.A large amount of sulfurous gas in process of production, discharges in a large amount of thermal power plants.The sulfurous gas that enters atmosphere is contaminate environment seriously, destroys the eubiosis, causes acid rain harm, and infringement HUMAN HEALTH, affects China's sustainable economic development.Due to the requirement of environment protection, national Ge great heat power plant has installed flue gas desulfurization (FGD) unit in succession.This just brings another environmental issue: in flue gas desulfurization course, produced a large amount of by product-desulfurized gesso of flue gas, yet FGD gypsum becomes solid waste., grade and the plaster of paris of desulfurized gesso of flue gas are suitable, containing terra alba, reach more than 95%.The desulfurized gesso of flue gas of take can be prepared semi-hydrated gypsum as raw material.Semi-hydrated gypsum is divided into alpha-semi water plaster stone and β-semi-hydrated gypsum.Alpha-semi water plaster stone is more complete than β-semi-hydrated gypsum compact crystallization, and coarse grains is even, and water paste ratio is low.Thereby having higher intensity, purposes is more extensive.
By desulfurized gesso of flue gas Dehydration, for alpha-semi water plaster stone, mainly contain autoclave method, hydrothermal method and normal pressure salt solustion mehtod.Wherein autoclave method needs larger facility investment, and normal pressure salt solustion mehtod is that desulfurated plaster fine powder is joined in certain density salts solution, adds some auxiliary agents, mixture is heated to boiling temperature Dehydration under normal pressure for alpha-semi water plaster stone.The method equipment is simple, be convenient to industrialization.But alpha-semi water plaster stone crystallization belongs to thermodynamic unstable system in salts solution, in different solution environmentals, with needle-like, column, the crystal habit such as granular, occur.Processing condition are restive.Needle-like alpha-semi water plaster stone has higher water paste ratio, and intensity is less; And granular and column alpha-semi water plaster stone has lower water paste ratio, intensity is larger.In addition, add more auxiliary agent that production cost is improved.In patent CN101113084A, we disclose normal pressure salt solustion mehtod and have prepared the controlled alpha-semi water plaster stone of pattern, and the alpha-semi water plaster stone folding strength of granular crystal reaches 7.7MPa, and ultimate compression strength reaches 33MPa.The report of relevant research preparing alpha-hemihydrate gypsum with desulfurated gypsum is both at home and abroad less, and wherein US Patent No. 5562892 has been reported with desulfurized gesso of flue gas and prepared needle-like and column alpha-semi water plaster stone, but wherein said method is comparatively complicated.
Summary of the invention
The object of the invention, be the intensity that further improves on the basis of existing technology alpha semi-hydrated gypsum, reduce costs, simplify preparation technology, provide a kind of and take desulfurized gesso of flue gas as main raw material, the method by hydro-thermal legal system for the alpha semi-hydrated gypsum of uniform short hexagonal columnar.
The present invention is achieved by following technical solution.
A method that desulfurized gesso of flue gas is converted into high strength alpha semi-hydrated gypsum, has following steps:
(1) prepare desulfurated plaster slurries
By desulfurized gesso of flue gas, be that mix 1:4～10 with water according to solid-liquid mass ratio, being uniformly mixed into faint yellow slurries is desulfurated plaster slurries, then puts into 250mL autoclave;
(2) in the desulfurated plaster slurries that obtain to step (1), add medium crystallization agent, synthetic mixed serum, the mass ratio of desulfurized gesso of flue gas and medium crystallization agent is 1:0.1～0.3, described medium crystallization agent is magnesium chloride hexahydrate;
(3) in the mixed serum obtaining to step (2) again, add crystal habit modifying agent, the mass ratio of desulfurized gesso of flue gas and crystal habit modifying agent is 1:0.2%～0.5%, and described crystal habit modifying agent is succinic acid;
(4) turn brilliant
Sealed high pressure reactor, the mixed serum that step (3) is obtained, at 110～120 ℃ of insulation 2-3 hour, completes terra alba to the crystal conversion of alpha semi-hydrated gypsum, and autoclave cools to 80～90 ℃ naturally;
(5) filter and wash
The mixed serum filtered while hot of the alpha semi-hydrated gypsum that step (4) is obtained, 80 ℃ of hot tap waters washings are 2～3 times for filter cake, dry 2～4 hours in 80 ℃, make high strength alpha semi-hydrated gypsum.
The solid-liquid mass ratio of the preferred desulfurized gesso of flue gas of described step (1) and water is 1:8.
The preferred terra alba of described step (4) is 118 ℃ to the crystal conversion temperature of alpha semi-hydrated gypsum.
Beneficial effect of the present invention: preparation technology is simple, by water-heat process, under the effect of a small amount of medium crystallization agent and crystal habit modifying agent, desulfurated plaster dehydration, the length-to-diameter ratio that has obtained homogeneous is less than 1 short hexagonal columnar alpha semi-hydrated gypsum; Its folding strength reaches 14.7MPa, and ultimate compression strength reaches 46.5MPa.In addition, production unit is simple, convenient operation is controlled, is easy to industrialization, with short production cycle, and raw materials cost is low.Therefore, enforcement of the present invention can reduce the exploitation in plaster of paris ore deposit, can turn waste into wealth again, and protection of the environment.
Accompanying drawing explanation
Fig. 1 is the SEM photo of the alpha semi-hydrated gypsum crystal morphology of embodiment 1;
Fig. 2 only adds the SEM photo that medium crystallization agent does not add the alpha semi-hydrated gypsum crystal morphology of crystal habit modifying agent;
Fig. 3 had not both added the SEM photo that medium crystallization agent does not add the alpha semi-hydrated gypsum crystal morphology of crystal habit modifying agent yet.
Embodiment
Below by specific embodiment, the present invention will be further described.
Embodiment 1
50 grams of desulfurized gesso of flue gas are put into 250mL autoclave with 200mL tap water, stir 10 minutes homogeneous desulfurated plaster slurries of mixed formation; Then in reactor, add 9 grams of magnesium chloride hexahydrates and 0.2 gram of succinic acid, stir dissolving in 10 minutes.Sealed high pressure reactor also puts it in thermostat container, in 120 ℃ of insulations 2 hours, completes terra alba to the crystal conversion of alpha semi-hydrated gypsum; Then take out autoclave, cooling 5 minutes of room temperature, cools to 60 ℃ naturally.Open autoclave lid, filtered while hot, filter cake adopts 500mL80 ℃ of tap water washing 2 times, then the filter cake after washing is put into 80 ℃ of loft drier and dries 2 hours, makes high strength alpha semi-hydrated gypsum.
After tested, the folding strength of the standard model that embodiment 1 makes reaches 14.7MPa, and ultimate compression strength reaches 46.5MPa.
Fig. 1 is the SEM photo of the alpha semi-hydrated gypsum crystal morphology of embodiment 1, has both added medium crystallization agent and has also added crystal habit modifying agent, and the length-to-diameter ratio of its crystal is less than 1.Fig. 2 has only added medium crystallization agent and the SEM photo that do not add the alpha semi-hydrated gypsum crystal morphology of crystal habit modifying agent, and the length-to-diameter ratio of its crystal is greater than 1.Fig. 3 had not both added the SEM photo that medium crystallization agent does not add the alpha semi-hydrated gypsum crystal morphology of crystal habit modifying agent yet, was fine acicular crystal, and the length-to-diameter ratio of its crystal is greater than 1.
Embodiment 2
40 grams of desulfurized gesso of flue gas are put into 250mL autoclave with 200mL tap water, stir 10 minutes homogeneous desulfurated plaster slurries of mixed formation; Then in reactor, add 8 grams of magnesium chloride hexahydrates and 0.16 gram of succinic acid, stir dissolving in 10 minutes.Sealed high pressure reactor also puts it in thermostat container, in 110 ℃ of insulations 3 hours, completes terra alba to the crystal conversion of alpha semi-hydrated gypsum; Then take out autoclave, cooling 5 minutes of room temperature, cools to 60 ℃ naturally.Open autoclave lid, filtered while hot, filter cake adopts 500mL80 ℃ of tap water washing 2 times, then the filter cake after washing is put into 80 ℃ of loft drier and dries 2 hours, makes high strength alpha semi-hydrated gypsum.
After tested, the folding strength of the standard model that embodiment 2 makes reaches 14.0MPa, and ultimate compression strength reaches 45.2MPa.
Embodiment 3
45 grams of desulfurized gesso of flue gas are put into 250mL autoclave with 200mL tap water, stir 10 minutes homogeneous desulfurated plaster slurries of mixed formation; Then in reactor, add 7 grams of magnesium chloride hexahydrates and 0.15 gram of succinic acid, stir dissolving in 10 minutes.Sealed high pressure reactor also puts it in thermostat container, in 115 ℃ of insulations 3 hours, completes terra alba to the crystal conversion of alpha semi-hydrated gypsum; Then take out autoclave, cooling 5 minutes of room temperature, cools to 60 ℃ naturally.Open autoclave lid, filtered while hot, filter cake adopts 500mL80 ℃ of tap water washing 2 times, then the filter cake after washing is put into 80 ℃ of loft drier and dries 2 hours, makes high strength alpha semi-hydrated gypsum.After tested, the folding strength of the standard model that embodiment 3 makes reaches 13.9MPa, and ultimate compression strength reaches 44.0MPa.
Claims (3)
1. desulfurized gesso of flue gas is converted into a method for high strength alpha semi-hydrated gypsum, there are following steps:
(1) prepare desulfurated plaster slurries
By desulfurized gesso of flue gas, be that mix 1:4～10 with water according to solid-liquid mass ratio, being uniformly mixed into faint yellow slurries is desulfurated plaster slurries, then puts into 250mL autoclave;
(2) in the desulfurated plaster slurries that obtain to step (1), add medium crystallization agent, synthetic mixed serum, the mass ratio of desulfurized gesso of flue gas and medium crystallization agent is 1:0.1～0.3, described medium crystallization agent is magnesium chloride hexahydrate;
(3) in the mixed serum obtaining to step (2) again, add crystal habit modifying agent, the mass ratio of desulfurized gesso of flue gas and crystal habit modifying agent is 1:0.2%～0.5%, and described crystal habit modifying agent is succinic acid;
(4) turn brilliant
Sealed high pressure reactor, the mixed serum that step (3) is obtained, at 110～120 ℃ of insulation 2-3 hour, completes terra alba to the crystal conversion of alpha semi-hydrated gypsum, and autoclave cools to 80～90 ℃ naturally;
(5) filter and wash
The mixed serum filtered while hot of the alpha semi-hydrated gypsum that step (4) is obtained, 80 ℃ of hot tap waters washings are 2～3 times for filter cake, dry 2～4 hours in 80 ℃, make high strength alpha semi-hydrated gypsum.
2. a kind of method that desulfurized gesso of flue gas is converted into high strength alpha semi-hydrated gypsum according to claim 1, is characterized in that, the solid-liquid mass ratio of the preferred desulfurized gesso of flue gas of described step (1) and water is 1:8.
3. a kind of method that desulfurized gesso of flue gas is converted into high strength alpha semi-hydrated gypsum according to claim 1, is characterized in that, the preferred terra alba of described step (4) is 118 ℃ to the crystal conversion temperature of alpha semi-hydrated gypsum.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104211485A (en) * | 2014-09-17 | 2014-12-17 | 中化化肥有限公司重庆磷复肥工程技术研究中心 | Method for producing crystalline potassium dihydrogen phosphate and potassium nitrate macroelement water-soluble fertilizer |
| CN104386932A (en) * | 2014-10-21 | 2015-03-04 | 北京科技大学 | Method for preparing alpha-type high-strength gypsum by using pellet flue gas desulfurization gypsum |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2167978A1 (en) * | 1995-01-26 | 1996-07-27 | Donald W. Kirk | Process for the production of alpha hemihydrate calcium sulfate from flue gas desulfurization materials |
| CN1800070A (en) * | 2006-01-10 | 2006-07-12 | 南京一夫建材实业有限公司 | Alpha type high-strength gypsum and its preparation method |
| CN101113084A (en) * | 2007-07-06 | 2008-01-30 | 天津大学 | Method for preparing shape-controlled alpha-semi-hydrated gypsum by using flue gas desulfurized gypsum |
-
2014
- 2014-05-05 CN CN201410186215.7A patent/CN103979811A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2167978A1 (en) * | 1995-01-26 | 1996-07-27 | Donald W. Kirk | Process for the production of alpha hemihydrate calcium sulfate from flue gas desulfurization materials |
| CN1800070A (en) * | 2006-01-10 | 2006-07-12 | 南京一夫建材实业有限公司 | Alpha type high-strength gypsum and its preparation method |
| CN101113084A (en) * | 2007-07-06 | 2008-01-30 | 天津大学 | Method for preparing shape-controlled alpha-semi-hydrated gypsum by using flue gas desulfurized gypsum |
Non-Patent Citations (2)
| Title |
|---|
| 段珍华等: "《脱硫石膏制备高强α—半水石膏的晶形改良剂与工艺参数研究》", 《新型建筑材料》, no. 8, 31 August 2008 (2008-08-31) * |
| 王立明: "脱硫石膏生产高强度α半水石膏资源化技术", 《2011中国建筑材料联合会石膏建材分会第二届年会暨第六届全国石膏技术交流大会暨展览会论文集》, 30 June 2011 (2011-06-30) * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104211485A (en) * | 2014-09-17 | 2014-12-17 | 中化化肥有限公司重庆磷复肥工程技术研究中心 | Method for producing crystalline potassium dihydrogen phosphate and potassium nitrate macroelement water-soluble fertilizer |
| CN104386932A (en) * | 2014-10-21 | 2015-03-04 | 北京科技大学 | Method for preparing alpha-type high-strength gypsum by using pellet flue gas desulfurization gypsum |
| CN104386932B (en) * | 2014-10-21 | 2016-05-25 | 北京科技大学 | A kind of method that uses pelletizing desulfurized gesso of flue gas to prepare α-type high strength gypsum |
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Application publication date: 20140813 |