CN102649627A - Method for preparing active lime by calcining limestone - Google Patents
Method for preparing active lime by calcining limestone Download PDFInfo
- Publication number
- CN102649627A CN102649627A CN2012101881055A CN201210188105A CN102649627A CN 102649627 A CN102649627 A CN 102649627A CN 2012101881055 A CN2012101881055 A CN 2012101881055A CN 201210188105 A CN201210188105 A CN 201210188105A CN 102649627 A CN102649627 A CN 102649627A
- Authority
- CN
- China
- Prior art keywords
- lime
- active lime
- limestone
- calcining
- quickened lime
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
The invention discloses a method for preparing active lime by calcining limestone. The limestone is calcined under the conditions of pressure intensity of 0.15-0.65 MPa and calcining temperature of 1,075-1,400 DEG C, so that the active lime can be obtained. According to the method, the limestone is calcined under the condition of improving the pressure intensity of the system; and the obtained active lime has the characteristics of large pore size, high activity and high milk production rate. The method has the advantages of simple used equipment, simple and reliable process and easiness in industrial implementation. The active lime obtained by the method has large pore size which is generally 0.5-4 mum, high activity which is generally greater than 400 ml (4NHCl, 10 minutes), and high milk production rate which is generally 4.30-5.05 ml/g.
Description
Technical field
The present invention relates to a kind of preparation method of lime, especially a kind of calcined limestone prepares the method for quickened lime.
Background technology
Lime (being unslaked lime) obtains through calcined limestone, chalk, shell etc., has in fields such as metallurgy, building, chemical industry, environment, agriculturals widely to use.
The production process of lime comes down to lime carbonate (CaCO
3) process of decomposes, its reaction formula is following:
CaCO
3(s) CaO(s)?+?CO
2(g) (1)
CaCO
3Decomposition reaction be a heterogeneous thermo-negative reaction, according to thermodynamic argument, desire to make reaction (1) to carry out to the right, can take following measure: product C O is reduced in (1)
2The dividing potential drop of gas
, help reaction and move to generating the CaO direction; Therefore (2), improve temperature and help reaction and move to generating the CaO direction because this reaction is thermo-negative reaction.These two measures are the basic norms that instruct lime to produce.In actual production, in order to reduce CO in the limestone kiln
2Dividing potential drop often adopts negative-pressure operation, promptly constantly extracts kiln gas out through induced draft fan, reduces
, to accelerate CaCO
3Decomposition rate.
Yet; The activity degree of present industrial lime is very not high; The activity degree of the lime that various processes is produced differs greatly, and the activity degree of the lime that traditional shaft furnace is produced is lower, basically all below 300ml; And the activity degree of the lime of producing with wheat Wurz kiln and rotary kiln is higher relatively, generally can reach 320～360ml.
Activity degree is an important indicator that characterizes lime quality.The method of inspection of activity of lime is that 50 gram lime are stirred digestion fast in 2 liters 40 ℃ water, as indicator, uses concentration to be 4molL with phenolphthalein reagent
-1HCl with the Ca that produces in the lime slaking process (OH)
2Neutralization.Must keep the point of equivalent of aquation N-process in the checkout procedure, promptly just change into colourless by redness.The consumption of hydrochloric acid when writing down lucky 10 minutes shows the activity degree of lime with the milliliter numerical table that consumed hydrochloric acid in 10 minutes.
Quickened lime is called soft burnt lime or soft calcined lime again; Compare with common lime, slagging speed is fast in steel melting furnace, can improve dephosphorization and desulfurization efficient 80%; Shorten the heat about 10%; Reduce lime consumption 10～30%, fluorite consumption saves 25～30%, thereby can improve the quality of steel, the output that increases steel, reduction steel-making cost.Facts have proved: adopted the enterprise of quickened lime steel-making, all obtained remarkable economic efficiency (Guo Shihan. the application of quickened lime in metallurgical production. fire-resistant and lime, 2007,32 (5): 1-2.).Sintering is one of effective measure of intensified-sintered process, raising agglomerate output with addition of quickened lime; Research shows; Adopt quickened lime can make sintering raising the output 8% or more (Li Yuanying. sintering is with addition of the experimental study of quickened lime. Sichuan metallurgy, 2004, (5): 54-56.).
Contain a large amount of SO in the mankind's activity combustion of fossil fuels discharged flue gas
2Gas, SO
2Environment has been caused serious destruction.Lime is a kind of aboundresources, wide material sources and cheap sweetening agent; Problems such as the equipment of wet desulphurization existence is perishable because dry desulfurization has overcome, fouling obstruction; And not having discharge of wastewater, invest advantages such as relatively low, is a kind of rising flue gas desulfurization technique.At present, dry flue gas desulphurization efficient is high less than wet method, and its major cause is exactly desulfurization reaction product CaSO
4(52.2cm
3Mol
-1) than sweetening agent CaO (16.8 cm
3Mol
-1) have bigger molecular volume (Cheng Shiqing, Feng Yubin, Lu Chunmei. the dynamics research of shell desulfurization performance. Proceedings of the CSEE; 2005; 25 (19): 80-85.), the expansion of volume will make the sorbent particle internal capillary reduce or stop up SO in the desulphurization reaction process
2Can't pass through fine and close CaSO
4Layer arrives sweetening agent inside and carries out desulphurization reaction, causes desulfuration efficiency and calcium utilization to reduce.
Cheng Shiqing etc. (Cheng Shiqing etc. the microvoid structure of shell and Wingdale and desulfurization performance thereof. combustion science and technology, 2005,11 (1): 24-28.) compared the desulfurization performance of shell and lime, the discovery shell has stronger sweetening power.Although the specific surface area of lime is very big, mean pore size is little, has only 0.05 μ m; The diffusional resistance of gas is also very big in this spilehole; Reactant gases is difficult to diffuse to granule interior, causes inner a large amount of surface-area not react, and average response speed is not high.Shell calcining back forms the above macropore of diameter 0.1 μ m, and these macropores make the diffusibility of gas in the hole strengthen the SO in the hole
2Concentration is bigger, and almost whole particle is participated in reaction simultaneously, so desulphurization reaction speed is just fast.Have more macroporous quickened lime though can prepare, yet shell is collected difficulty, can't carry out large-scale industrial production with shell.
In order to obtain the high lime of activity degree, the Zhang Xianfu of Institutes Of Technology Of Hebei has proposed the method (method of obtaining active lime by vacuum calcining limestone and device, the patent No.: ZL 200610012556.8) of calcined limestone under vacuum condition.Because calcining can reduce calcining temperature under vacuum condition, this method can obtain the quickened lime of activity degree 380～450ml.Yet this method can only adopt the indirect heating mode, and this mode exists heat transfer efficiency low, can't carry out large-scale industrial production, and therefore, applying of this method is restricted.
Summary of the invention
But the technical problem that the present invention will solve provides the method that a kind of calcined limestone of large-scale industrial production prepares quickened lime.
For solving the problems of the technologies described above, the technical scheme that the present invention taked is: described Wingdale is that 0.15～0.65MPa, calcining temperature are to calcine under 1075～1400 ℃ the condition at pressure, can obtain quickened lime.
Wingdale of the present invention is at N
2Calcine under the atmosphere.Described pressure and calcining temperature are linear relationship, and pressure height then calcining temperature is high.
Limestone calcination generates the process of lime except CaCO
3Be decomposed into CaO and CO
2Outside, the recrystallize of simultaneous CaO and crystal growth.When calcining temperature was on the low side, if calcination time is short, then the material center was difficult for reaching CaCO
3Decomposition temperature, can only generate the CaO nucleus and grow up at the shallow table of particulate, thereby insufficient burnt phenomenon occur, generally be called to give birth to and burn, the product activity degree is lower naturally.And when calcining temperature is higher, CaCO
3Decompose rapidly, but the speed of CaO recrystallize and crystal growth is also very fast.In this case, if calcination time is long, then be prone to make the CaO crystal grain of formation excessive, hole is too small, also can cause the product activity degree to reduce.The activity of lime is not only relevant with CaO crystal grain, and closely related with pore dimension, porosity.And these parameters and the relating to parameters of Wingdale in calcination process specifically are exactly relevant with calcining temperature, time and pressure.The calcined limestone under condition of high voltage of the invention property utilizes the cooperation of high pressure and calcining temperature, obtains quickened lime.
Adopt the beneficial effect that technique scheme produced to be: the present invention is calcined limestone under the condition that improves system pressure, and the quickened lime of acquisition has the advantages that pore dimension is big, activity degree is high, the galactopoiesis rate is high.Equipment used of the present invention is simple, simple and reliable process, be easy in industry, implement.
The resulting quickened lime of the present invention has bigger pore dimension, is generally 0.5～4 μ m; Activity degree is high, generally greater than 400ml (4N HCl, 10min); The galactopoiesis rate is high, is generally 4.30～5.05ml/g.
Embodiment
Below in conjunction with specific embodiment the present invention is done further detailed explanation.
Embodiment 1: the method that this calcined limestone prepares quickened lime adopts following process step.
With particle diameter is the Wingdale of the 10～20mm crucible of packing into, and crucible is put into electric furnace.At first vacuumize, feed N then
2, pressure is risen to 0.15MPa.Electric furnace is warming up to 1075 ℃, constant temperature 2h, and outage cooling then treats that temperature reduces to room temperature, takes out crucible after the pressure release.The pore dimension of prepared quickened lime is 0.5～2 μ m, and activity degree is 411ml, and the galactopoiesis rate is 4.68ml/g.
Embodiment 2: the method that this calcined limestone prepares quickened lime adopts following process step.
With particle diameter is the Wingdale of the 10～20mm crucible of packing into, and crucible is put into electric furnace.At first vacuumize, feed N then
2, pressure is risen to 0.40MPa.Electric furnace is warming up to 1300 ℃, constant temperature 2h, and outage cooling then treats that temperature reduces to room temperature, takes out crucible after the pressure release.The pore dimension of prepared quickened lime is 0.5～3.5 μ m, and activity degree is 437ml, and the galactopoiesis rate is: 5.05ml/g.
Embodiment 3: the method that this calcined limestone prepares quickened lime adopts following process step.
With the Wingdale of the particle diameter 10～20mm crucible of packing into, crucible is put into electric furnace.At first vacuumize, feed N then
2, pressure is risen to 0.65MPa.Electric furnace is warming up to 1400 ℃, constant temperature 2h, and outage cooling then treats that temperature reduces to room temperature, takes out crucible after the pressure release.The pore dimension of prepared quickened lime is 1～4 μ m, and activity degree is 419ml, and the galactopoiesis rate is 4.30ml/g.
Claims (3)
1. a calcined limestone prepares the method for quickened lime, it is characterized in that: described Wingdale is that 0.15～0.65MPa, calcining temperature are to calcine under 1075～1400 ℃ the condition at pressure, can obtain quickened lime.
2. calcined limestone according to claim 1 prepares the method for quickened lime, it is characterized in that: described Wingdale is at N
2Calcine under the atmosphere.
3. calcined limestone according to claim 1 and 2 prepares the method for quickened lime, it is characterized in that: described pressure and calcining temperature are linear relationship, and pressure height then calcining temperature is high.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012101881055A CN102649627A (en) | 2012-06-08 | 2012-06-08 | Method for preparing active lime by calcining limestone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012101881055A CN102649627A (en) | 2012-06-08 | 2012-06-08 | Method for preparing active lime by calcining limestone |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102649627A true CN102649627A (en) | 2012-08-29 |
Family
ID=46691759
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012101881055A Pending CN102649627A (en) | 2012-06-08 | 2012-06-08 | Method for preparing active lime by calcining limestone |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102649627A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105000811A (en) * | 2015-07-24 | 2015-10-28 | 东北大学 | Parallel flow heat accumulating type lime kiln production technology based on CO2 accumulation |
| CN108706604A (en) * | 2018-07-04 | 2018-10-26 | 福建工程学院 | A kind of wet method prepares method for preparation of modified bentonite |
| CN112010573A (en) * | 2020-08-31 | 2020-12-01 | 安徽工业大学 | Preparation method and use method of quick-dissolving lime for converter slag |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101293744A (en) * | 2008-06-12 | 2008-10-29 | 武汉理工大学 | Impulse composite combustion method in breeze and natural gas mix combustion |
| CN101570406A (en) * | 2009-06-11 | 2009-11-04 | 北京市琉璃河水泥有限公司 | Calcination process of active lime |
| CN101987783A (en) * | 2010-08-27 | 2011-03-23 | 莱芜钢铁股份有限公司 | Method for producing active pulverized lime by utilizing coal gas to calcine limestone through suspended state pre-heating decomposing furnace |
-
2012
- 2012-06-08 CN CN2012101881055A patent/CN102649627A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101293744A (en) * | 2008-06-12 | 2008-10-29 | 武汉理工大学 | Impulse composite combustion method in breeze and natural gas mix combustion |
| CN101570406A (en) * | 2009-06-11 | 2009-11-04 | 北京市琉璃河水泥有限公司 | Calcination process of active lime |
| CN101987783A (en) * | 2010-08-27 | 2011-03-23 | 莱芜钢铁股份有限公司 | Method for producing active pulverized lime by utilizing coal gas to calcine limestone through suspended state pre-heating decomposing furnace |
Non-Patent Citations (2)
| Title |
|---|
| 仲兆平等: "Caroline石灰石热分解实验研究", 《燃烧科学与技术》 * |
| 宁静涛等: "微细石灰石粉末高温煅烧分解研究", 《燃烧科学与技术》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105000811A (en) * | 2015-07-24 | 2015-10-28 | 东北大学 | Parallel flow heat accumulating type lime kiln production technology based on CO2 accumulation |
| CN108706604A (en) * | 2018-07-04 | 2018-10-26 | 福建工程学院 | A kind of wet method prepares method for preparation of modified bentonite |
| CN112010573A (en) * | 2020-08-31 | 2020-12-01 | 安徽工业大学 | Preparation method and use method of quick-dissolving lime for converter slag |
| CN112010573B (en) * | 2020-08-31 | 2022-02-25 | 安徽工业大学 | Preparation method and use method of quick-dissolving lime for converter slag |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Ma et al. | Preparation of a morph-genetic CaO-based sorbent using paper fibre as a biotemplate for enhanced CO2 capture | |
| Sun et al. | Utilization of lime mud from paper mill as CO2 sorbent in calcium looping process | |
| Yuan et al. | CaO/Ca (OH) 2 thermochemical heat storage of carbide slag from calcium looping cycles for CO2 capture | |
| CN100334026C (en) | Process for prepering active magnesium oxide | |
| Chi et al. | CO2 capture performance of CaO modified with by-product of biodiesel at calcium looping conditions | |
| Zhang et al. | Investigation on a novel CaO–Y2O3 sorbent for efficient CO2 mitigation | |
| Ma et al. | Fabrication and CO2 capture performance of magnesia-stabilized carbide slag by by-product of biodiesel during calcium looping process | |
| CN106745118B (en) | A kind of magnalium hydrotalcite and the method for preparing magnalium hydrotalcite | |
| Xu et al. | Study on the effect of NaBr modification on CaO-based sorbent for CO2 capture and SO2 capture | |
| Zou et al. | Sorption capacity and mechanism of Cr3+ on tobermorite derived from fly ash acid residue and carbide slag | |
| Yang et al. | Novel low cost Li4SiO4-based sorbent with naturally occurring wollastonite as Si-source for cyclic CO2 capture | |
| Li et al. | High-temperature CO2 capture by Li4SiO4 adsorbents: Effects of pyroligneous acid (PA) modification and existence of CO2 at desorption stage | |
| Ma et al. | Development of Mn/Mg-copromoted carbide slag for efficient CO2 capture under realistic calcium looping conditions | |
| CN103818939B (en) | Hydrogen peroxide fluid bed special aluminium oxide and production technology | |
| CN110745824A (en) | Method for regulating and controlling coal-based porous carbon pore matching based on trace potassium source catalytic activation | |
| Skoufa et al. | Evaluating the activity and stability of CaO-based sorbents for post-combustion CO2 capture in fixed-bed reactor experiments | |
| Luo et al. | Effect of different organic compounds on the preparation of CaO-based CO2 sorbents derived from wet mixing combustion synthesis | |
| CN105733724A (en) | Sulfur-fixation efficiently combusted clean coal with desulfuration effect and preparation method | |
| Yue et al. | Influence of additives on CaCO3 precursors and multicycle CO2 capture performance of CaO sorbents | |
| CN108499515B (en) | Doped CO2Preparation method of calcium-based adsorbent | |
| CN102649627A (en) | Method for preparing active lime by calcining limestone | |
| CN102815926A (en) | High-temperature calcium-based coal ash absorbent for CO2 and preparation method of high-temperature calcium-based coal ash absorbent | |
| Wang et al. | Study on CO2 sorption performance and sorption kinetics of Ce-and Zr-doped CaO-based sorbents | |
| Hu et al. | Structurally improved Li4SiO4 sorbents derived from lithium salicylate precursor for enhanced CO2 capture | |
| CN101804998A (en) | Method for producing high-purity magnesium oxide by using dolomite |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20120829 |