CN100584789C - Method for preparing high-calcium fly-ash cement with high-calcium fly-ash - Google Patents
Method for preparing high-calcium fly-ash cement with high-calcium fly-ash Download PDFInfo
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- CN100584789C CN100584789C CN200810018379A CN200810018379A CN100584789C CN 100584789 C CN100584789 C CN 100584789C CN 200810018379 A CN200810018379 A CN 200810018379A CN 200810018379 A CN200810018379 A CN 200810018379A CN 100584789 C CN100584789 C CN 100584789C
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- cement
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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
- C04B7/00—Hydraulic cements
- C04B7/24—Cements from oil shales, residues or waste other than slag
- C04B7/26—Cements from oil shales, residues or waste other than slag from raw materials containing flue dust, i.e. fly ash
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
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Abstract
The invention discloses a process for preparing high calcium fly ash cement by high calcium fly ashes. A combustion chamber is arranged at the head part of the existing ball mill for pre-mixing measured high calcium fly ashes and a digesting agent and then feeding measured cement clinker, gypsum, blast furnace slag, etc. into a ball mill for ball grinding; and the material temperature in the mill is rising under the mechanical action of the mill, additionally, the grinding head combustion chamber provides heat, so the water in the digestion solution is evaporated and the digestion solution and free calcium oxide in the high calcium fly ashes have the mechanical and chemical action, the free calcium oxide digestion is realized during the cement grinding process, and finally the high calcium fly ash cement is prepared. The process is simple and needs not to add the special high calcium ash treating process before producing the cement, the free calcium oxide digestion effect is obvious, the mixing amount of the high calcium ashes in the cement can be greatly increased and the cement manufacturing cost is reduced. The process overcomes the defect that the humidity-control and digestion of fly ash free calcium oxide need two to seven days, and can implement the continuous production, and the ball-milling efficiency of the cement mill is improved by over 10 percent in the meantime.
Description
Technical field
The present invention relates to the preparation method of pulverized fuel ash cement, be specifically related to a kind of method for preparing high calcium fly-ash cement with high-calcium fly ass.
Background technology
As everyone knows, calcium oxide content is called high-calcium fly ass greater than the flyash of 10% (weight) in flyash.High-calcium fly ass is owing to contain free calcium oxide, if directly apply in cement and the concrete use after, tend to cause cement or the defective problem of volume of concrete stability, for construction work brings hidden danger, country has carried out strict restriction to the content of free calcium oxide in the high-calcium fly ass for this reason.According to the technological standard of the relevant high-calcium fly ass of country, most of high-calcium fly ass can not directly add in cement or the concrete and uses, and need carry out modification to high-calcium fly ass and handle.
According to relative national standards, be called Portland fly ash cement (abbreviation pulverized fuel ash cement), code name PF by Portland clinker and flyash, hydraulic cementing materials that proper amount of gypsum is levigate to be made.Doping quantity of fly ash is 20%～40% by mass percentage in the cement.
In fact, flyash has broad variety, according to the difference of chemical constitution, mainly contains high calcium ash and low calcium fly ash.Owing to there is free calcium oxide, make the volume of high calcium ash in cement in the high-calcium fly ass, so do not reach the requirement that the flyash of preparation pulverized fuel ash cement requirement accounts for 20-40% usually less than 10%.In order to improve volume, be necessary free calcium oxide in the high calcium ash is cleared up.
The method that free calcium oxide is cleared up in the high-calcium fly ass has a lot, and the principle difference according to clearing up free calcium oxide can be divided into physics method and chemical method.
The physics method is carried out mechanical grinding to flyash exactly, reach certain fineness after, free calcium oxide is met water and is cleared up rapidly, can not bring stability problem to cement or concrete.But this method often requires the fineness of high-calcium fly ass grinding enough carefully, and the fineness of flyash is less than 30 microns and can reaches the qualified requirement of stability sometimes, so though this method technology is simple, have the energy consumption height, defect of high cost.
Chemical method by making high calcium ash be excited by chemical admixture to adding chemical substance such as vitriol etc. in the flyash, reaches the purpose of clearing up free calcium oxide exactly.The characteristics that this method is outstanding are the chemical substance cost height that added, and cause the also high defective of modified coal ash cost.
Also having a kind of is exactly the method that damping is handled, and this method is simple and cost is low, but flyash damping process is not easy operation, has the automated job that is not easy to realize environmental protection on the technology, brings defectives such as difficulty for scale operation.
Summary of the invention
It is simple to the purpose of this invention is to provide a kind of technology, cost is low, in preparation pulverized fuel ash cement process, do not increase complex apparatus and operation, increase a kind of method for preparing high calcium fly-ash cement with high-calcium fly ass of the volume of high-calcium fly ass with the simplest method.
In order to overcome the defective of prior art, technical scheme of the present invention is to solve like this: a kind of high-calcium fly ass prepares the method for high calcium fly-ash cement, is undertaken by following step:
(1), at first a combustion chamber is set at existing ball mill head, the addition of the flyash after the metering is 18 parts～40 parts, describedly clear up agent and comprise that digestion solution or solid clear up agent, the described addition of clearing up agent is 0.8 part～3.5 parts of high-calcium fly ass weight, carries out premix with mechanical system in delivering into the process of grinding machine.
(2), above-mentioned compound through premix is sent into ball mill in the lump and carried out ball milling with 60 parts～70 parts cement clinkers, 4 parts～6 parts gypsum, 4 parts～12 parts blast-furnace slags again;
(3), high calcium fly-ash cement goes out the abrasive particle degree and is controlled at＜45 microns, it tails over less than 15%;
(4), under the mechanical effect of grinding machine, temperature of charge raises in the grinding machine, moisture evaporation in the digestion solution, be controlled in 100 ℃-180 ℃ the scope with the required mechanico-chemical reaction temperature of the free calcium oxide generation mechanochemical treatment in the high-calcium fly ass, grind in the process at cement and to realize clearing up of free calcium oxide, finally make high-calcium fly ass content and be 18 parts～40 parts high calcium fly-ash cement.
(5), by the exhaust gas volumn that the combustion chamber that adjust to feed grinding machine produces, dewfall not when mill tail fly-ash separator solid and gas is separated prevents that sack cleaner from sticking with paste bag.
By in cement pulverizing course, the interpolation applicant applies for a patent and (clears up the method for clearing up agent and clearing up free calcium oxide in the high-calcium fly ass of free calcium oxide, application number: a kind of liquid of clearing up free calcium oxide 200810017534.X) is cleared up agent, clearing up of the calcium oxide that in cement pulverizing course, dissociates in the realization high-calcium fly ass, thereby the volume of high calcium ash in the raising cement.
In order to guarantee to grind the moisture evaporation in the interior material, mechanico-chemical reaction takes place, in grinding machine, fully realize clearing up of free calcium oxide, the present invention is provided with the combustion chamber at the ball mill bistrique, the high-temperature gas that the combustion chamber produces feeds grinding machine, adds material in the defibrator process, guarantees moisture evaporation, after reaction is finished, realize that by fly-ash separator solid and gas separates at the mill tail, the while is owing to the setting of combustion chamber, the temperature that has also guaranteed to grind gas, prevent to grind tail sack cleaner dewfall, guarantee the fly-ash separator works better.
The present invention compared with prior art, characteristics of the present invention are:
At first to prepare the technology of high calcium fly-ash cement simple in the present invention, need before producing cement, not increase high calcium ash treatment facility and technology specially, as long as before common cement ball mill, set up the combustion chamber,, powdered coal ash can realize technical scheme of the present invention for increasing mixing equipment.
Secondly, it is remarkable that free calcium oxide of the present invention is cleared up effect, can significantly increase the volume of high calcium ash in cement, and the cement manufacturing cost reduces.Because mechanical mill has reduced the particle size of free calcium oxide, clear up the levigate free calcium oxide surface that chemical substance in the agent can be rapid and fresh mechanico-chemical reaction takes place, raising along with temperature of charge, clearing up speed of response increases substantially, clearing up agent moisture not only plays homodisperse and clears up the effect that chemical substance and flyash fully contact, and water vapor has also played the purpose of clearing up free calcium oxide, so that free calcium oxide of the present invention is cleared up effect is remarkable.
The 3rd, add material and the principle of utilizing temperature of charge rising in the ball milling material process in the defibrator process by before ball mill, setting up the combustion chamber, flyash damping process is realized in the process of ball milling of cement, overcome damping and cleared up the flyash free calcium oxide and need 2-7 days drawback, realized continuous production.
The 4th, because digestion solution itself also is a grinding aid, in clearing up the process of free calcium oxide, can also improve the cement mill grinding efficiency more than 10%.
Description of drawings:
Fig. 1 is the closed circuit ball milling preparation flow of high calcium fly-ash cement figure;
Fig. 2 is high calcium fly-ash cement open circuit ball milling preparation flow figure.
Embodiment
Below in conjunction with accompanying drawing the present invention is described in further detail:
Figure 1 shows that the closed circuit ball milling preparation flow of high calcium fly-ash cement figure, the high-calcium fly ass raw material through belt weigher metering back and equally in proportion clearing up of metering carry out machinery on the conveying belt of agent before entering grinding machine bistrique feed bin and be pre-mixed, cement clinker after high-calcium fly ass and the pre-composition of clearing up agent and the metering and gypsum enter in the lump and are admitted to grinding machine behind the bistrique feed bin and carry out ball milling.In the process of material ball milling, the flue gas heating material that the combustion chamber that bistrique is provided with produces, the feasible moisture evaporation of clearing up in the agent, free calcium oxide is cleared up.Go out grind materials and carry out classification by powder separating machine, qualified powder enters the finished cement storehouse, and the coarse particles material returns ball mill and continues levigate.
Figure 2 shows that high calcium fly-ash cement open circuit ball milling preparation flow figure, control mill feed material amount is guaranteed mill cement and is met granularity requirements.Owing in the ball mill working process, must carry out dedusting to grinding machine discharge port place, often adopt the sack cleaner dedusting, in order to guarantee the sack cleaner works better, need to regulate gas fume of combustion chamber and enter the grinding machine flow, when guaranteeing to clear up the temperature of free calcium oxide, guarantee not occur dedusting gas dewfall and stick with paste the bag phenomenon.
Embodiment 1
Cement clinker is the high-quality grog that adopts high-quality rotary kiln production line to produce.
The plaster of paris: the G class or the above gypsum or the anhydrite of category-A secondary (containing) that should meet regulation among the GB/T 5483.Industry by-product gypsum: be the byproduct of main component with calcium sulfate in the industrial production.When adopting industry by-product gypsum, must be through overtesting, proving can be harmless to water-based.
Slag is the granulated blast-furnace slag that meets GB/T203.
To be calcium oxide content increase the desulfurization high calcium ash that calcium produces greater than 10% thermal power plant's flyash or low calcium fly ash through desulfurization to high calcium ash.
Clearing up agent is that number of patent application is that the liquid or solid free calcium oxide of describing among the 200810017534.X is cleared up material.Implementation step:
(1), at first a combustion chamber is set at existing ball mill head, the addition of the flyash after the metering is 18 parts～40 parts, describedly clear up agent and comprise that digestion solution or solid clear up agent, the described addition of clearing up agent is 0.8 part～3.5 parts of high-calcium fly ass weight, carries out premix with mechanical system in delivering into the process of grinding machine.
(2), above-mentioned compound through premix is sent into ball mill in the lump with 60 parts～70 parts cement clinkers, 4 parts～6 parts gypsum, 4 parts～12 parts blast-furnace slags again, carry out ball milling;
(3), high calcium fly-ash cement goes out the abrasive particle degree and is controlled at＜45 microns, it tails over less than 15%;
(4), under the mechanical effect of grinding machine, temperature of charge raises in the grinding machine, moisture evaporation in the digestion solution, be controlled in 100 ℃-180 ℃ the scope with the required mechanico-chemical reaction temperature of the free calcium oxide generation mechanochemical treatment in the high-calcium fly ass, grind in the process at cement and to realize clearing up of free calcium oxide, finally make high-calcium fly ass content and be 18 parts～40 parts high calcium fly-ash cement.
Embodiment 2
70 parts of cement clinkers; 20 parts of high-calcium fly asses; 5 parts in gypsum; 5 parts of blast-furnace slags; Add that to clear up agent be 1 part of high-calcium fly ass weight; The material top temperature is 120 ℃ in the control grinding machine, cement goes out the abrasive particle degree and tails over less than 15% for 45 microns, the gained pulverized fuel ash cement meets every set quota among the GB 1344-1999 " Portland blast, Portland pozzolana cement and Portland fly ash cement national standard ", and other steps are with embodiment 1.
Embodiment 3
Cement clinker: 65 parts; 25 parts of high-calcium fly asses; 5 parts in gypsum; Blast-furnace slag: 5 parts; Add that to clear up agent be 1.5 parts of high-calcium fly ass weight; The material top temperature is 150 ℃ in the control grinding machine, cement goes out the abrasive particle degree and tails over less than 15% for 45 microns, the gained pulverized fuel ash cement meets every set quota among the GB 1344-1999 " Portland blast, Portland pozzolana cement and Portland fly ash cement national standard ", and other steps are with embodiment 1.
Embodiment 4
Cement clinker: 60 parts; 30 parts of high-calcium fly asses; 5 parts in gypsum; Blast-furnace slag: 5 parts; Add that to clear up agent be 2.0 parts of high-calcium fly ass weight; The material top temperature is 160 ℃ in the control grinding machine, cement goes out the abrasive particle degree and tails over less than 10% for 45 microns, the gained pulverized fuel ash cement meets every set quota among the GB 1344-1999 " Portland blast, Portland pozzolana cement and Portland fly ash cement national standard ", and other steps are with embodiment 1.
Embodiment 5
Cement clinker: 60 parts; 25 parts of high-calcium fly asses; 5 parts in gypsum; 10 parts of blast-furnace slags; Add that to clear up agent be 3 parts of high-calcium fly ass weight; The material top temperature is 170 ℃ in the control grinding machine, cement goes out abrasive particle degree 45 tm screen in 15%, the gained pulverized fuel ash cement meets every set quota among the GB 1344-1999 " Portland blast, Portland pozzolana cement and Portland fly ash cement national standard ", and other steps are with embodiment 1.
Embodiment 6
Cement clinker: 60 parts; 35 parts of high-calcium fly asses; 5 parts in gypsum; 5 parts of blast-furnace slags; Add that to clear up agent be 2 parts of high-calcium fly ass weight; The material top temperature is 120 ℃ in the control grinding machine, cement goes out the abrasive particle degree and tails over less than 10% for 45 microns, the gained pulverized fuel ash cement meets every set quota among the GB 1344-1999 " Portland blast, Portland pozzolana cement and Portland fly ash cement national standard ", and other steps are with embodiment 1.
Claims (3)
1, a kind ofly prepare the method for high calcium fly-ash cement, it is characterized in that being undertaken by following step with high-calcium fly ass:
(1), the high-calcium fly ass after the metering with clear up agent and carry out premix, the addition of its described high-calcium fly ass is 18 parts～40 parts, describedly clear up agent and comprise that digestion solution or solid clear up agent, the described addition of clearing up agent is 0.8 part～3.5 parts of high-calcium fly ass weight, carries out premix with mechanical system;
(2), above-mentioned flyash and pre-composition and 60 parts～70 parts cement clinkers, 4 parts～6 parts gypsum, 4 parts～12 parts blast-furnace slags of clearing up agent are sent into ball mill in the lump, carry out ball milling;
(3), a combustion chamber is set at the ball mill head, be 100 ℃-180 ℃ by the temperature of charge in the high-temperature flue gas heat balls grinding machine after the fuel combustion, make that the material in the ball mill reaches the temperature of clearing up free calcium oxide in mechanical milling process;
(4), under the mechanical effect of grinding machine and under the heat effect of gas fume of combustion chamber, temperature of charge raises in the grinding machine, moisture evaporation in the digestion solution, be controlled in 100 ℃-180 ℃ the scope with the required mechanico-chemical reaction temperature of the free calcium oxide generation mechanochemical treatment in the high-calcium fly ass, grind in the process at cement and to realize clearing up of free calcium oxide, finally make high-calcium fly ass content and be 18 parts～40 parts high calcium fly-ash cement;
(5), high calcium fly-ash cement goes out the abrasive particle degree and is controlled at＜45 microns, it tails over less than 15%.
2, according to claim 1ly a kind ofly prepare the method for high calcium fly-ash cement, it is characterized in that the required mechanico-chemical reaction temperature of free calcium oxide generation mechanochemical treatment in described and the high-calcium fly ass is controlled in 120 ℃-170 ℃ the scope with high-calcium fly ass.
3. according to claim 1ly a kind ofly prepare the method for high calcium fly-ash cement, it is characterized in that described ball mill is traditional ball mill or Vertical Mill with high-calcium fly ass; Grinding process is an open circuit or closed circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810018379A CN100584789C (en) | 2008-06-04 | 2008-06-04 | Method for preparing high-calcium fly-ash cement with high-calcium fly-ash |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810018379A CN100584789C (en) | 2008-06-04 | 2008-06-04 | Method for preparing high-calcium fly-ash cement with high-calcium fly-ash |
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| Publication Number | Publication Date |
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| CN101279824A CN101279824A (en) | 2008-10-08 |
| CN100584789C true CN100584789C (en) | 2010-01-27 |
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102584060A (en) * | 2012-02-28 | 2012-07-18 | 上海宝田新型建材有限公司 | Method for preparing secondary coal ash of goods by using high-calcium coal ash |
| CN103553390B (en) * | 2013-10-18 | 2015-12-23 | 中冶东方工程技术有限公司 | The digestion procedure of flyash free calcium oxide and application thereof |
| CN112811877A (en) * | 2021-01-15 | 2021-05-18 | 沈阳建筑大学 | Fly ash activity excitation method and high-calcium fly ash cement with large mixing amount |
| CN113588399A (en) * | 2021-07-29 | 2021-11-02 | 宝武集团环境资源科技有限公司 | Quick digestion method for free calcium oxide in metallurgical dust and mud |
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2008
- 2008-06-04 CN CN200810018379A patent/CN100584789C/en not_active Expired - Fee Related
Non-Patent Citations (2)
| Title |
|---|
| 使高钙粉煤灰安定性合格技术措施的研究. 韩如福，孙家瑛，陆文雄等.粉煤灰，第3期. 2004 |
| 使高钙粉煤灰安定性合格技术措施的研究. 韩如福，孙家瑛，陆文雄等.粉煤灰，第3期. 2004 * |
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| CN101279824A (en) | 2008-10-08 |
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