CN112209417B - Preparation method of light calcium carbonate powder for papermaking coating - Google Patents
Preparation method of light calcium carbonate powder for papermaking coating Download PDFInfo
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- C—CHEMISTRY; METALLURGY
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- C01F11/00—Compounds of calcium, strontium, or barium
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- C01F11/181—Preparation of calcium carbonate by carbonation of aqueous solutions and characterised by control of the carbonation conditions
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- C01F11/00—Compounds of calcium, strontium, or barium
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- C01F11/182—Preparation of calcium carbonate by carbonation of aqueous solutions and characterised by an additive other than CaCO3-seeds
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- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
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Abstract
The invention relates to a preparation method of light calcium carbonate powder, aiming at the problem that the light calcium carbonate has higher viscosity and is not beneficial to papermaking coating, the invention provides a preparation method of the light calcium carbonate powder for papermaking coating, which comprises the following steps: calcining limestone to prepare quicklime, putting the quicklime into a lime slaker for wet digestion to obtain calcium hydroxide slurry, removing impurities, separating, pumping into a curing tank for aging to obtain calcium hydroxide raw slurry, and adjusting the mass concentration and the temperature of the calcium hydroxide raw slurry; then adding a water-soluble plant macromolecular compound into the calcium hydroxide raw slurry, uniformly stirring and pumping into a circulating bubbling carbonization tower for carbonation reaction, pumping out the calcium carbonate cooked slurry after the reaction is finished, and separating and dehydrating to obtain light calcium carbonate dehydrated powder; drying and screening the light calcium carbonate dehydrated powder to obtain light calcium carbonate powder. The invention utilizes the water-soluble plant macromolecular compound to regulate the crystallization and growth processes of the calcium carbonate particles to prepare the low-viscosity light calcium carbonate powder, has simple process and high stability, and can realize industrial production.
Description
Technical Field
The invention relates to a preparation method of light calcium carbonate powder, in particular to a preparation method of light calcium carbonate powder for papermaking coating.
Background
Light calcium carbonate (PCC) has long been used as a coating pigment in paper production, with inherent advantages in terms of purity, whiteness, particle regularity and particle size distribution compared to Ground Calcium Carbonate (GCC), and therefore, the smoothness, finish, opacity and printability of PCC coatings are considerably higher than those of GCC. However, the light calcium carbonate undergoes a plurality of physical and chemical reaction processes, the characteristics of particle ultra-fineness and high porosity are obvious, the particle gap is large, the surface charge polarity is large, the interfacial activity is good, and the water absorption is strong, so that the viscosity of the slurry is far higher than that of GCC (glass reinforced ceramic) with relatively inert interface under the same condition, the quality and the efficiency of coating production are adversely affected, and the application of the light calcium carbonate in the aspect of papermaking coating is limited. At present, the research on the viscosity formation and the influence mechanism of the light calcium carbonate is less, and the mature regulation and control process is not disclosed yet. There are generally two ways to reduce viscosity: firstly, a small amount of heavy calcium carbonate is added into light calcium carbonate slurry or dry powder, and the viscosity reduction is achieved formally by increasing the specific gravity, but the disadvantages are that the sedimentation volume, the particle size distribution and the like are negatively influenced; secondly, the light calcium carbonate slurry is ground by a wet method, and various surfactants and dispersants are used for improving the particle regularity and the dispersity of light calcium particles to achieve the purpose of reducing the viscosity, and the method generally has the problems of complex process, high energy consumption, large reagent addition amount, uneconomic industrial production and the like. Therefore, there is a need for an improved method for preparing light calcium carbonate powder for papermaking coating.
Disclosure of Invention
The invention aims to overcome the problem that the light calcium carbonate is high in viscosity and not beneficial to papermaking coating, and provides a preparation method of light calcium carbonate powder for papermaking coating.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of light calcium carbonate powder for papermaking coating comprises the following steps:
(1) calcining limestone to prepare quicklime;
(2) putting quicklime into a lime slaking machine for wet digestion to obtain calcium hydroxide slurry, sieving with a 80-325 mesh sieve to remove impurities, separating by a suspension separator, pumping into a curing tank for aging to obtain calcium hydroxide raw slurry, and adjusting the mass concentration of the calcium hydroxide raw slurry to 10-13% at the temperature of 30-40 ℃;
(3) adding water-soluble plant macromolecular compound into the calcium hydroxide raw slurry, wherein the adding amount of the water-soluble plant macromolecular compound is 1-5% of the solid content of the calcium hydroxide, uniformly stirring, pumping into a circulating bubbling carbonization tower, and reacting with CO2And (4) carrying out carbonation reaction, pumping out the calcium carbonate cooked slurry after the reaction is finished, separating by a suspension separator, and dehydrating by a centrifuge to obtain the light calcium carbonate dehydrated powder.
(4) The light calcium carbonate dehydrated powder is dried from high to low in multiple stages until the moisture content is lower than 1 percent, and then is screened by a screening machine to obtain the light calcium carbonate powder.
The invention uses limestone to calcine to prepare quicklime, and the quicklime is put into a lime slaking machine to be digested by a wet method to obtain the low-viscosity limeFiltering the calcium hydroxide slurry by a screen to remove large-particle impurities, removing high-specific-gravity fine impurities by a suspension separator, pumping the calcium hydroxide slurry into a curing pool for aging for later digestion to obtain calcium hydroxide slurry, and then removing impurities, separating and aging to obtain calcium hydroxide raw slurry; adjusting the concentration and temperature of the raw slurry, adding a certain amount of water-soluble plant macromolecular compound, stirring, and feeding into a circulating bubble carbonization tower to react with CO2Performing carbonation reaction to prepare cooked calcium carbonate slurry, wherein the water-soluble plant macromolecular compound can regulate and control the crystallization and growth processes of calcium carbonate particles, and then removing impurities, performing solid-liquid separation and dehydration on the cooked slurry to obtain light calcium carbonate dehydrated powder; the light calcium carbonate dehydrated powder is subjected to multi-stage drying and screening to obtain light calcium carbonate powder with the water content of less than 1%, and the finished product water content is controlled within 1% to ensure that the calcium carbonate is not remarkably yellowed. The invention adopts a circulating bubbling carbonization process to realize the adjustment of the morphology, the geometric dimension and the micro interface state of the calcium carbonate crystal under the regulation and control of the water-soluble plant macromolecular compound, so that the calcium carbonate crystal has submicron-grade geometric dimension, regular small spindle morphology and narrower particle size distribution interval, the viscosity of the calcium carbonate water slurry is obviously reduced, the maximum reduction amplitude can reach more than 95 percent under the same condition, the calcium carbonate slurry with high filling amount is easily prepared, the calcium carbonate slurry can be used as a filler for the coating production of various high-grade paper products, and the coating quality and the production efficiency of a scraper are obviously improved. And overcomes the defects of the traditional viscosity reduction method that light calcium is mixed with exogenous natural minerals (heavy calcium carbonate, silicon micropowder and the like) and calcium carbonate slurry refined particles are ground at high speed, has the advantages of simple process, adjustable viscosity index, no harmful additive, low production cost and the like, and is easy to carry out industrial production and application and popularization.
Preferably, the calcination temperature in step (1) is 900-950 ℃. The invention adopts lower temperature to fully calcine the limestone, thereby not only saving energy, but also preparing the quicklime with higher purity and proper activity.
Preferably, the quicklime with the purity of more than 93 percent and the activity degree of 90-110 ℃ is taken out in the step (1).
Preferably, the ratio of the digestive juice to the solid in the wet digestion in the step (2) is 6.0-7.5, and the digestion temperature is lower than 75 ℃.
Preferably, the aging time in step (2) is 12 to 16 hours.
Preferably, the water-soluble plant macromolecules are added in the step (3) in an amount of 1-3% of the solid content of the calcium hydroxide.
Preferably, the water-soluble plant macromolecule in the step (3) is one or more of pregelatinized starch, modified corn starch, sweet potato starch, water-soluble starch, dextran, hydroxy cellulose and methyl cellulose.
Preferably, the water content of the dehydrated light calcium carbonate powder in the step (3) is controlled to be 25-35%.
Preferably, the temperature of the third-stage drying in the step (4) is controlled to be 230-180-130 ℃.
Preferably, the screen of the screen mill in the step (4) is 200 meshes. The screen cloth used by the powder screening machine is preferably 200 meshes, the fineness of finished powder is ensured, the production flux is also considered, frequent damage of the screen cloth is avoided, and the production smoothness is improved.
Therefore, the invention has the following beneficial effects: (1) the method takes industrially produced quicklime as a main raw material, and adopts a circulating bubbling carbonization process to realize the adjustment of the morphology, the geometric dimension and the micro-interface state of the calcium carbonate crystal under the regulation and control of a water-soluble plant macromolecular compound, so that the calcium carbonate crystal has submicron-grade geometric dimension, regular small spindle morphology and a narrow particle size distribution interval, and the viscosity of the calcium carbonate water slurry is obviously reduced; (2) the low-viscosity light calcium carbonate powder prepared by the method has the characteristic of ultra-fine fineness, and has higher coating smoothness, brightness, opacity and printability as a paper-making coating pigment on the premise that the comprehensive cost is equal to that of the conventional light calcium carbonate; (3) the method overcomes the defects of the traditional viscosity reduction method that light calcium is mixed with exogenous natural minerals (heavy calcium carbonate, silicon micropowder and the like) and calcium carbonate slurry refined particles are ground at high speed, has the advantages of simple process, adjustable viscosity index, no harmful additive, low production cost and the like, and is easy to carry out industrial production and application and popularization.
Description of the drawings:
FIG. 1 is a flow chart of the preparation of the present invention
Fig. 2 is a microscopic morphology (TEM) of precipitated calcium carbonate prepared by the present invention.
Detailed Description
The technical solution of the present invention is further illustrated by the following specific examples.
In the present invention, unless otherwise specified, all the raw materials and equipment used are commercially available or commonly used in the art, and the methods in the examples are conventional in the art unless otherwise specified. The quicklime activity is tested by referring to patent publication No. CN105445324B, namely a quick determination method for quicklime chemical reaction activity.
Example 1
(1) Feeding the limestone subjected to washing, impurity removal and airing into a full-automatic shaft kiln, controlling the working temperature of a calcination area to be 900 ℃, keeping the low flow velocity to perform blast calcination for 24 hours, and obtaining quick lime with the purity of not less than 93 percent and the activity degree of 90 ℃ for a minute;
(2) removing coal ash and fly ash from the quicklime by a drum screen, feeding the quicklime into a squirrel cage lime slaking machine, and carrying out wet slaking under the conditions of liquid-solid ratio of 6.0 and slaking temperature of 65 ℃ to obtain low-viscosity calcium hydroxide slurry; filtering with 80 mesh, 120 mesh, 200 mesh and 325 mesh screens to remove large particle impurities, removing high specific gravity fine impurities by a suspension separator, pumping into a curing tank, aging for 12 h to obtain calcium hydroxide raw slurry, pumping the calcium hydroxide raw slurry into a carbonization workshop, and adjusting the mass concentration to be 13 +/-0.1% and the temperature to be 30 +/-0.5 ℃;
(3) adding 1.5% of pregelatinized corn starch (based on the solid content of calcium hydroxide) into the calcium hydroxide raw slurry, stirring, and pumping into a pump of 30m3In the high-flux circulating bubbling carbonization tower, the bottom jet type circulating pump flow of the carbonization tower is controlled to be about 300 m3The kiln gas flow is controlled to be about 3200 m3And h, continuously carbonizing for about 90 min, finishing the carbonation reaction when the pH value of the slurry is less than 7.5, pumping out the calcium carbonate cooked slurry from the bottom of the carbonization tower, removing impurities again through a suspension separator, feeding into a homogenizing tank, stirring, homogenizing, pumping into a centrifugal machine, and dehydrating to obtain the water content of 30.8% of dehydrated light calcium carbonate powder;
(4) drying the light calcium carbonate dehydrated powder at three stages of high temperature, medium temperature and low temperature (230-180-130 ℃) until the water content is less than 1 percent, and screening the light calcium carbonate dehydrated powder by a screening machine with a 200-mesh screen to obtain the finished product MPCC-1 of the low-viscosity light calcium carbonate powder.
Example 2
The same as in (1) of example 1;
removing coal ash and fly ash from the quicklime by a drum screen, feeding the quicklime into a squirrel cage lime slaking machine, and carrying out wet slaking under the conditions of liquid-solid ratio of 6.0 and slaking temperature of 65 ℃ to obtain low-viscosity calcium hydroxide slurry; filtering with 80 mesh, 120 mesh, 200 mesh and 325 mesh screens to remove large particle impurities, removing high specific gravity fine impurities by a suspension separator, pumping into a curing tank, aging for 12 h to obtain calcium hydroxide raw slurry, pumping the calcium hydroxide raw slurry into a carbonization workshop, and adjusting the mass concentration to be 13 +/-0.1% and the temperature to be 35 +/-0.5 ℃;
adding dextran 1.0% and water soluble starch 1.0% (based on calcium hydroxide solid content) into calcium hydroxide raw slurry, stirring, and pumping into a pump of 30m3In the high-flux circulating bubbling carbonization tower, the flow of a jet type circulating pump at the bottom of the carbonization tower is controlled to be about 400m3The kiln gas flow is controlled to be about 3100m3Performing continuous carbonization for about 89 min, finishing carbonation reaction when the pH value of the slurry is less than 7.5, pumping out the calcium carbonate cooked slurry from the bottom of the carbonization tower, removing impurities again through a suspension separator, feeding the slurry into a homogenizing tank, stirring and homogenizing, and pumping the slurry into a centrifuge for dehydration to obtain light calcium dehydrated powder with the water content of 33.5 percent;
(4) drying the light calcium carbonate dehydrated powder at three stages of high temperature, medium temperature and low temperature (230-180-130 ℃) until the water content is less than 1 percent, and screening by a screening machine to obtain the finished product MPCC-2 of the low-viscosity light calcium carbonate powder.
Example 3
(1) The same as in (1) of example 1;
(2) removing coal ash and fly ash from the quicklime by a drum screen, feeding the quicklime into a squirrel cage lime slaking machine, and carrying out wet slaking under the conditions of liquid-solid ratio of 6.0 and slaking temperature of 65 ℃ to obtain low-viscosity calcium hydroxide slurry; filtering with 80 mesh, 120 mesh, 200 mesh and 325 mesh screens to remove large particle impurities, removing high specific gravity fine impurities by a suspension separator, pumping into a curing tank, aging for 12 h to obtain calcium hydroxide raw slurry, pumping the calcium hydroxide raw slurry into a carbonization workshop, and adjusting the mass concentration to be 13 +/-0.1% and the temperature to be 30 +/-0.5 ℃;
(3) adding water soluble starch 1.5% and hydroxy cellulose 0.5% (based on calcium hydroxide solid content) into calcium hydroxide raw slurry, stirring, and pumping into a pump of 30m3In the high-flux circulating bubbling carbonization tower, the flow of a jet type circulating pump at the bottom of the carbonization tower is controlled to be about 400m3The kiln gas flow is controlled to be about 3100m3The carbonization lasts for about 89 min, when the pH value of the slurry is less than 7.5, the carbonation reaction is finished, and the flow of the bottom jet type circulating pump of the carbonization tower is controlled to be about 400m3The kiln gas flow is controlled to be about 3100m3Performing continuous carbonization for about 89 min, finishing carbonation reaction when the pH value of the slurry is less than 7.5, pumping out the calcium carbonate cooked slurry from the bottom of the carbonization tower, removing impurities again through a suspension separator, feeding the slurry into a homogenizing tank, stirring and homogenizing, and pumping the slurry into a centrifuge for dehydration to obtain light calcium dehydrated powder with the water content of 31.9 percent;
(4) drying the light calcium carbonate dehydrated powder at three stages of high temperature, medium temperature and low temperature (230-170-120 ℃) until the water content is less than 1 percent, and screening by a screening machine to obtain the finished product MPCC-3 of the low-viscosity light calcium carbonate powder.
Example 4
(1) Feeding the limestone subjected to washing, impurity removal and airing into a full-automatic shaft kiln, controlling the working temperature of a calcination area to be 950 ℃, keeping the low flow velocity to perform blast calcination for 20 hours, and obtaining quick lime with the purity of not less than 93 percent and the activity degree of 110 ℃ for min;
(2) removing coal ash and fly ash from the quicklime by a drum screen, feeding the quicklime into a squirrel cage lime slaking machine, and carrying out wet slaking under the conditions of liquid-solid ratio of 7.5 and slaking temperature of 70 ℃ to obtain low-viscosity calcium hydroxide slurry; filtering with 80 mesh, 120 mesh, 200 mesh and 325 mesh screens to remove large particle impurities, removing high specific gravity fine impurities by a suspension separator, pumping into a curing tank, aging for 16 h to obtain calcium hydroxide raw slurry, pumping the calcium hydroxide raw slurry into a carbonization workshop, and adjusting the mass concentration to 10 +/-0.1% and the temperature to 40 +/-0.5 ℃;
(3) adding 5 percent of modified corn starch (calculated by the solid content of the calcium hydroxide) into the raw calcium hydroxide slurry, uniformly stirring, and pumping into a pump with the diameter of 30m3In the high-flux circulating bubbling carbonization tower, the bottom jet type circulating pump flow of the carbonization tower is controlled to be about 300 m3The kiln gas flow is controlled to be about 3200 m3Performing continuous carbonization for about 90 min, finishing the carbonation reaction when the pH value of the slurry is less than 7.5, pumping out the calcium carbonate cooked slurry from the bottom of the carbonization tower, removing impurities again through a suspension separator, sending the slurry into a homogenizing tank, stirring and homogenizing the slurry, and pumping the slurry into a centrifuge for dehydration to obtain light calcium dehydrated powder with the water content of 25.1 percent;
(4) drying the light calcium carbonate dehydrated powder at three stages of high temperature, medium temperature and low temperature (230-180-130 ℃) until the water content is less than 1 percent, and screening the light calcium carbonate dehydrated powder by a screening machine with a 200-mesh screen to obtain a low-viscosity light calcium carbonate powder finished product MPCC-4.
Example 5
(1) Feeding the limestone subjected to washing, impurity removal and airing into a full-automatic shaft kiln, controlling the working temperature of a calcination area to be 930 ℃, keeping the low flow velocity and blasting for calcination for 24 hours to obtain quick lime with the purity of not less than 93 percent and the activity degree of 100 ℃ for a minute;
(2) removing coal ash and fly ash from the quicklime by a drum screen, feeding the quicklime into a squirrel cage lime slaking machine, and carrying out wet slaking under the conditions of liquid-solid ratio of 7.0 and slaking temperature of 50 ℃ to obtain low-viscosity calcium hydroxide slurry; filtering with 80 mesh, 120 mesh, 200 mesh and 325 mesh screens to remove large particle impurities, removing high specific gravity fine impurities by a suspension separator, pumping into a curing tank, aging for 15 h to obtain calcium hydroxide raw slurry, pumping the calcium hydroxide raw slurry into a carbonization workshop, and adjusting the mass concentration to be 12 +/-0.1% and the temperature to be 35 +/-0.5 ℃;
(3) adding 1% of sweet potato starch, 1% of glucan and 1% of methyl cellulose (based on the solid content of calcium hydroxide) into the calcium hydroxide raw slurry, stirring uniformly, and pumping into a pump with a volume of 30m3In the high-flux circulating bubbling carbonization tower, the bottom jet type circulating pump flow of the carbonization tower is controlled to be about 300 m3The kiln gas flow is controlled to be about 3200 m3Carbonizing for about 90 min, completing carbonation reaction when pH value of slurry is less than 7.5, pumping out calcium carbonate slurry from bottom of carbonization tower, separating suspensionRemoving impurities again, feeding the mixture into a homogenizing tank, stirring and homogenizing, and pumping the mixture into a centrifugal machine for dehydration to obtain light calcium carbonate dehydrated powder with the water content of 35.0%;
(4) drying the light calcium carbonate dehydrated powder at three stages of high temperature, medium temperature and low temperature (220-180-140 ℃) until the water content is less than 1 percent, and screening the light calcium carbonate dehydrated powder by a screening machine with a 200-mesh screen to obtain the finished product MPCC-5 of the low-viscosity light calcium carbonate powder.
Comparative example 1
Washing with water to remove impurities, and calcining the air-dried limestone at 1050 deg.C to obtain the product;
removing coal ash and powder head from quicklime by a drum screen, feeding the quicklime into a cage lime slaker for full wet slaking, controlling the liquid-solid ratio to be about 5 and the slaking temperature to be 80 ℃ to obtain calcium hydroxide slurry, filtering the calcium hydroxide slurry by 80-mesh, 120-mesh, 200-mesh and 325-mesh screens to remove large-particle impurities, removing high-specific-gravity fine impurities by a suspension separator, pumping the calcium hydroxide slurry into a slaking tank for ageing for 12 hours to obtain calcium hydroxide raw slurry, and pumping the calcium hydroxide raw slurry into a carbonization workshop to adjust the concentration to be 10 percent and the temperature to be 30 ℃;
feeding calcium hydroxide into a bubbling carbonization tower for carbonation reaction, pumping out calcium carbonate cooked slurry from the carbonization tower after the carbonation reaction is finished, removing impurities again through a suspension separator, homogenizing in a homogenizing tank, and feeding into a centrifuge for dehydration to obtain light calcium carbonate dehydrated powder;
drying the light calcium carbonate dehydrated powder in a disc type dryer with the working temperature of about 230 ℃ until the water content is less than 1.0 percent, and screening by a screening machine to obtain light calcium carbonate powder PCC-1.
Comparative example 2
(1) The same as (1) of comparative example 1;
(2) the same as (2) of comparative example 1;
(3) adding 10% of 2300-mesh ultrafine heavy calcium carbonate (calculated by the solid content of slurry) into the calcium hydroxide raw slurry, stirring and mixing at a high speed, and then sending the mixture into a dehydrator for dehydration to obtain dehydrated powder;
(4) drying the dehydrated powder in a disc type dryer with the working temperature of about 230 ℃ until the moisture content is less than 1 percent, and screening by a screening machine to obtain the light calcium carbonate powder PCC-2.
Comparative example 3
(1) The same as (1) of comparative example 1;
(2) removing coal ash and powder head from quicklime by a drum screen, feeding the quicklime into a cage lime slaker for full wet slaking, controlling the liquid-solid ratio to be about 5 and the slaking temperature to be 80 ℃ to obtain calcium hydroxide slurry, filtering the calcium hydroxide slurry by 80-mesh, 120-mesh, 200-mesh and 325-mesh screens to remove large-particle impurities, removing high-specific-gravity fine impurities by a suspension separator, pumping the calcium hydroxide slurry into a slaking tank for ageing for 12 hours to obtain calcium hydroxide raw slurry, and pumping the calcium hydroxide raw slurry into a carbonization workshop to adjust the concentration to be 30 percent and the temperature to be 30 ℃;
(3) adding 1.0% of sodium polyacrylate dispersant into the calcium hydroxide raw slurry, and feeding the mixture into a high-shear ball mill for full grinding to obtain ultrafine light calcium slurry; feeding the light calcium slurry into a plate-and-frame filter press for filter pressing and dehydration to obtain a filter cake with the water content of about 45%;
(4) and (3) sending the filter cake into a double-blade dryer with the working temperature of about 260 ℃ for primary drying, then sending into a disc dryer with the working temperature of about 200 ℃ for full drying until the water content is less than 1%, and screening by a screening machine to obtain the light calcium carbonate powder PCC-3.
And (3) performance testing: the specific surface area, the granularity and the viscosity of each light calcium carbonate powder product are tested. BET: heating a calcium carbonate sample to constant weight, and detecting by using a 3H-2000A type BET analyzer; granularity: distilled water is used as a dispersion medium, 10 percent calcium carbonate emulsion is prepared for sample injection detection, and a testing instrument is a BT-9300 laser particle size analyzer; viscosity: distilled water is used as a dispersion medium, calcium carbonate slurry with the solid content of 55% is prepared, the viscosity is detected after stirring for 10min, and a testing instrument is an NDJ-79 rotational viscometer.
| Sample numbering | BET,m2/g | D50, μm | D97, μm | Viscosity, centipoise |
| MPCC-1 | 11.36 | 2.448 | 7.137 | 75.3 |
| MPCC-2 | 14.73 | 2.302 | 7.721 | 67.5 |
| MPCC-3 | 13.05 | 2.471 | 7.839 | 39.5 |
| MPCC-4 | 12.84 | 2.298 | 7.440 | 42.19 |
| MPCC-5 | 11.95 | 2.365 | 7.605 | 51.80 |
| PCC-1 | 8.43 | 3.432 | 13.456 | 879.8 |
| PCC-2 | 7.61 | 4.178 | 15.911 | 135.3 |
| PCC-3 | 9.05 | 2.618 | 7.322 | 107.6 |
From the above table it can be seen that the precipitated calcium carbonate produced by the process has a significantly lower viscosity than the comparative example. Comparative example 1 is a general method for preparing light calcium carbonate, and comparative example 2 is a formal "viscosity reduction" by increasing specific gravity by adding a small amount of heavy calcium carbonate on the basis of comparative example 1, and it can be seen from the table that the particle size distribution is negatively affected; comparative example 3 the light calcium carbonate slurry is ground by a wet method, and a dispersant is added to improve the particle regularity and the dispersibility of the light calcium particles, so as to achieve the purpose of reducing the viscosity, and the viscosity and the particle size are superior to those of comparative example 2, but the method has the disadvantages of complex process, high energy consumption, large reagent addition amount and uneconomical industrial production. The invention uses the industrial production quicklime as the main raw material, and adopts the circulating bubbling carbonization process to realize the adjustment of the appearance, the geometric dimension and the micro interface state of the calcium carbonate crystal under the regulation and control of the water-soluble plant macromolecular compound, and the specific surface area of the low-viscosity light calcium carbonate powder prepared by the method can reach 14 m2In submicron form of the original grains, D50≤2μm、D97The coating is less than or equal to 8 mu m, has the characteristic of ultra-fine fineness, and has higher coating smoothness, brightness, opacity and printability when being used as a paper-making coating pigment on the premise that the comprehensive cost is equal to that of the conventional light calcium carbonate; the method overcomes the defects of the traditional viscosity reduction method that light calcium is mixed with exogenous natural minerals (heavy calcium carbonate, silicon micropowder and the like) and calcium carbonate slurry refined particles are ground at high speed, has the advantages of simple process, adjustable viscosity index, no harmful additive, low production cost and the like, and is easy to carry out industrial production and application and popularization.
Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (9)
1. The preparation method of the light calcium carbonate powder for papermaking coating is characterized by comprising the following steps: (1) calcining limestone to prepare quicklime;
(2) putting quicklime into a lime slaking machine for wet digestion to obtain calcium hydroxide slurry, sieving with a 80-325 mesh sieve to remove impurities, separating by a suspension separator, pumping into a curing tank for aging to obtain calcium hydroxide raw slurry, and adjusting the mass concentration of the calcium hydroxide raw slurry to 10-13% at the temperature of 30-40 ℃;
(3) adding water-soluble plant macromolecular compound into calcium hydroxide raw slurry, wherein the water-soluble plant macromolecular compound is one or more of pregelatinized starch, modified corn starch, sweet potato starch, water-soluble starch and glucan, the addition amount of the water-soluble plant macromolecular compound is 1% -5% of the solid content of the calcium hydroxide, and pumping the mixture into a circulating bubbling carbonization tower to react with CO after uniform stirring2Carrying out carbonationAfter the reaction, pumping out the calcium carbonate cooked slurry, separating by a suspension separator, and dehydrating by a centrifuge to obtain light calcium carbonate dehydrated powder; wherein the conditions of the circulating bubbling carbonization tower are as follows: bottom jet type circulating pump flow rate of 300 m at bottom of carbonization tower3Flow rate of kiln 3200 m3Flow rate of circulation pump at bottom of carbonization tower 400m3Flow rate of kiln 3100m3/h；
(4) The light calcium carbonate dehydrated powder is dried from high to low in multiple stages until the water content is lower than 1 percent, and then the light calcium carbonate powder of the spindle body is obtained by screening through a screening machine.
2. The method for preparing light calcium carbonate powder for papermaking coating as claimed in claim 1, wherein the calcination temperature in step (1) is 900-950 ℃.
3. The method for preparing light calcium carbonate powder for papermaking coating according to claim 1, characterized in that quick lime with purity of more than 93% and activity degree of 90-110 ℃ is taken in step (1).
4. The method for preparing light calcium carbonate powder for papermaking coating according to claim 1, wherein the solid-to-liquid ratio of the wet digestion solution in the step (2) is 6.0-7.5, and the digestion temperature is lower than 75 ℃.
5. The method for preparing light calcium carbonate powder for papermaking coating according to claim 1, wherein the aging time in the step (2) is 12-16 h.
6. The method for preparing light calcium carbonate powder for papermaking coating according to claim 1, wherein the amount of the water-soluble plant macromolecules added in the step (3) is 1% -3% of the solid content of calcium hydroxide.
7. The method for preparing light calcium carbonate powder for papermaking coating according to claim 1, wherein the moisture content of the light calcium carbonate dehydrated powder in the step (3) is 25% -35%.
8. The method for preparing light calcium carbonate powder for papermaking coating according to claim 1, wherein the tertiary drying temperature in the step (4) is controlled to be 230 ℃ to 180 ℃ to 130 ℃.
9. The method for preparing light calcium carbonate powder for papermaking coating according to claim 1, 2 or 3, wherein the screen of the screen machine in the step (4) is 200 meshes.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102583483A (en) * | 2012-02-22 | 2012-07-18 | 常州碳酸钙有限公司 | Preparation method of micrometer spindle composite nano-calcium carbonate |
| CN107344728A (en) * | 2016-05-05 | 2017-11-14 | 嘉峪关大友嘉镁钙业有限公司 | A kind of Production of Light Calcium Carbonate method for the white pipes of PVC |
| CN107555459A (en) * | 2017-09-13 | 2018-01-09 | 泰兴市诚盛化工有限公司 | A kind of preparation method of nanometer of spindle winnofil |
| CN108083314A (en) * | 2018-02-01 | 2018-05-29 | 青州宇信钙业股份有限公司 | A kind of preparation method of rice-shaped precipitated calcium carbonate |
| CN108975372A (en) * | 2018-07-12 | 2018-12-11 | 广西华纳新材料科技有限公司 | A kind of preparation method of spindle winnofil |
| CN109179471A (en) * | 2018-09-28 | 2019-01-11 | 河北化工医药职业技术学院 | A kind of preparation method with resistance to settling precipitated calcium carbonate |
| CN109455750A (en) * | 2018-12-12 | 2019-03-12 | 东升新材料（山东）有限公司 | A kind of modified abrasive light calcium and preparation method thereof |
-
2019
- 2019-08-28 CN CN201910802071.6A patent/CN112209417B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102583483A (en) * | 2012-02-22 | 2012-07-18 | 常州碳酸钙有限公司 | Preparation method of micrometer spindle composite nano-calcium carbonate |
| CN107344728A (en) * | 2016-05-05 | 2017-11-14 | 嘉峪关大友嘉镁钙业有限公司 | A kind of Production of Light Calcium Carbonate method for the white pipes of PVC |
| CN107555459A (en) * | 2017-09-13 | 2018-01-09 | 泰兴市诚盛化工有限公司 | A kind of preparation method of nanometer of spindle winnofil |
| CN108083314A (en) * | 2018-02-01 | 2018-05-29 | 青州宇信钙业股份有限公司 | A kind of preparation method of rice-shaped precipitated calcium carbonate |
| CN108975372A (en) * | 2018-07-12 | 2018-12-11 | 广西华纳新材料科技有限公司 | A kind of preparation method of spindle winnofil |
| CN109179471A (en) * | 2018-09-28 | 2019-01-11 | 河北化工医药职业技术学院 | A kind of preparation method with resistance to settling precipitated calcium carbonate |
| CN109455750A (en) * | 2018-12-12 | 2019-03-12 | 东升新材料（山东）有限公司 | A kind of modified abrasive light calcium and preparation method thereof |
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