Method for manufacturing nano calcium carbonate from high-concentration carbon dioxide industrial exhaust gases

Abstract

The invention provides a method for manufacturing a nano-grade calcium carbonate from high-concentration carbon dioxide industrial exhaust gases, which comprises the following steps: (1) adding a crystal nucleus forming accelerator into a suspension of a calcium hydroxide; (2), introducing a gas containing 50 to 100 volume percent of a carbon dioxide, adding a dispersant when a carbonization rate is over 80 percent, and continuously introducing the gas for 10 to 20min when the pH value of the suspension is reduced to between 6.5 and 7.0, wherein the final temperature of a reaction slurry liquid is 45 to 70 DEG C; and (3) adding the aqueous solution of a cladding agent into the suspension of the calcium hydroxide, wherein a cladding and activating time is 1 to 2h, and then collecting the nano-grade activated calcium carbonate from the reaction product. The method of the invention greatly reduces the equipment and operation costs, quickens the carbonization reaction, saves the time of the carbonization reaction and energy, reduces the energy consumption, increases the oversaturated concentration of the calcium carbonate, and finally generates narrowly distributed nano-grade calcium carbonate particles the grain size of which is uniform.

Description

technical field

[0001] The invention relates to a preparation method of calcium carbonate particles, more specifically, relates to a method for preparing nanometer calcium carbonate particles by using high-concentration carbon dioxide gas discharged from industry. technical background

[0002] The commonly used industrial production method of nano-calcium carbonate is bubbling carbonization method. The stirred tank carbonization method is a method widely used at home and abroad to produce nano-calcium carbonate. This method needs to strictly control the carbonization temperature at 10-30°C during the entire carbonization process, while The formation process of calcium carbonate is an exothermic reaction, so a huge forced cooling heat exchange system is required.

[0003] Chinese patent application publication CN1330039A discloses a method for synthesizing calcium carbonate by mechanical stirring and mixing at a relatively low temperature, then heating the calcium carbonate s...

Examples

Embodiment 1

[0025] at 60m 3 Add 50m 3 Calcium hydroxide concentration 10% (weight concentration) initial temperature is the lime emulsion of 25 ℃, add 20kg sucrose and 130kg triethanolamine at the same time, after stirring evenly, pass into the industrial gas that the carbon dioxide content is 95% (volume concentration) and start to carry out Carbonization reaction, when the carbonization rate reaches 90%, add 20.5kg magnesium chloride, continue to ventilate until slurry pH is 6.5-7, obtain the nano-calcium carbonate suspension that temperature is 63 ℃, add sodium stearate 250kg in this slurry Concentration of 7% (weight concentration) saponified emulsion, continue to stir for 1.5h for coating activation treatment, then filter the slurry while hot, dry at 100°C, and pulverize to obtain cubic and spherical transparent calcium carbonate. The carbonization reaction time is 110 minutes, and the method specified by the national standard (GB / T 19590-2004) is used for measurement. The main part...

Embodiment 2

[0027] at 60m 3 Add 50m 3 Calcium hydroxide concentration 8.5% (mass concentration) initial temperature is the refined lime emulsion of 30 ℃, add 81kg sucrose simultaneously, after stirring, pass into the industrial gas that carbon dioxide content is 78% (volume concentration) and begin to carry out carbonization reaction, When the carbonization rate reaches 80%, add 8.6kg sodium hexametaphosphate, and continue aeration until the pH of the slurry is 6.5-7 to obtain a nano-calcium carbonate suspension with a temperature of 55°C. Add 125kg of sodium stearate to the slurry. The saponified emulsion with a concentration of 5% (weight concentration) is continuously stirred for 2 hours to carry out coating activation treatment, the slurry is filtered while it is hot, and dried at 100° C. to obtain cubic and spherical nano-active calcium carbonate. The carbonization reaction time is 70 minutes, and the method specified in the national standard (GB / T 19590-2004) is used for measuremen...

Embodiment 3

[0029] at 60m 3 Add 50m 3Calcium hydroxide concentration 13% (mass concentration) initial temperature is the refined lime emulsion of 39 ℃, add 160kg sodium citrate at the same time, after stirring evenly, pass into the industrial gas that carbon dioxide content is 85% (volume concentration) and begin to carry out carbonization Reaction, when the carbonization rate reaches 95%, add 60kg of sodium bicarbonate, and continue to ventilate until the pH of the slurry is 6.5-7 to obtain a nano-calcium carbonate suspension with a temperature of 70°C, and add TC-311 titanic acid to the slurry Lipid coupling agent 85kg concentration is the aqueous solution of 15% (weight concentration), continues to stir 1h and carries out coating activation treatment, slurry is filtered while hot, through 100 ℃ of drying, pulverization promptly obtains cubic nano-active calcium carbonate. The carbonization reaction time is 120 minutes, and it is measured by the method stipulated in the national standa...

technical field

[0001] The invention relates to a preparation method of calcium carbonate particles, more specifically, relates to a method for preparing nanometer calcium carbonate particles by using high-concentration carbon dioxide gas discharged from industry. technical background

[0002] The commonly used industrial production method of nano-calcium carbonate is bubbling carbonization method. The stirred tank carbonization method is a method widely used at home and abroad to produce nano-calcium carbonate. This method needs to strictly control the carbonization temperature at 10-30°C during the entire carbonization process, while The formation process of calcium carbonate is an exothermic reaction, so a huge forced cooling heat exchange system is required.

[0003] Chinese patent application publication CN1330039A discloses a method for synthesizing calcium carbonate by mechanical stirring and mixing at a relatively low temperature, then heating the calcium carbonate s...

Examples

Embodiment 1

[0025] at 60m 3 Add 50m 3 Calcium hydroxide concentration 10% (weight concentration) initial temperature is the lime emulsion of 25 ℃, add 20kg sucrose and 130kg triethanolamine at the same time, after stirring evenly, pass into the industrial gas that the carbon dioxide content is 95% (volume concentration) and start to carry out Carbonization reaction, when the carbonization rate reaches 90%, add 20.5kg magnesium chloride, continue to ventilate until slurry pH is 6.5-7, obtain the nano-calcium carbonate suspension that temperature is 63 ℃, add sodium stearate 250kg in this slurry Concentration of 7% (weight concentration) saponified emulsion, continue to stir for 1.5h for coating activation treatment, then filter the slurry while hot, dry at 100°C, and pulverize to obtain cubic and spherical transparent calcium carbonate. The carbonization reaction time is 110 minutes, and the method specified by the national standard (GB / T 19590-2004) is used for measurement. The main part...

Embodiment 2

[0027] at 60m 3 Add 50m 3 Calcium hydroxide concentration 8.5% (mass concentration) initial temperature is the refined lime emulsion of 30 ℃, add 81kg sucrose simultaneously, after stirring, pass into the industrial gas that carbon dioxide content is 78% (volume concentration) and begin to carry out carbonization reaction, When the carbonization rate reaches 80%, add 8.6kg sodium hexametaphosphate, and continue aeration until the pH of the slurry is 6.5-7 to obtain a nano-calcium carbonate suspension with a temperature of 55°C. Add 125kg of sodium stearate to the slurry. The saponified emulsion with a concentration of 5% (weight concentration) is continuously stirred for 2 hours to carry out coating activation treatment, the slurry is filtered while it is hot, and dried at 100° C. to obtain cubic and spherical nano-active calcium carbonate. The carbonization reaction time is 70 minutes, and the method specified in the national standard (GB / T 19590-2004) is used for measuremen...

Embodiment 3

[0029] at 60m 3 Add 50m 3Calcium hydroxide concentration 13% (mass concentration) initial temperature is the refined lime emulsion of 39 ℃, add 160kg sodium citrate at the same time, after stirring evenly, pass into the industrial gas that carbon dioxide content is 85% (volume concentration) and begin to carry out carbonization Reaction, when the carbonization rate reaches 95%, add 60kg of sodium bicarbonate, and continue to ventilate until the pH of the slurry is 6.5-7 to obtain a nano-calcium carbonate suspension with a temperature of 70°C, and add TC-311 titanic acid to the slurry Lipid coupling agent 85kg concentration is the aqueous solution of 15% (weight concentration), continues to stir 1h and carries out coating activation treatment, slurry is filtered while hot, through 100 ℃ of drying, pulverization promptly obtains cubic nano-active calcium carbonate. The carbonization reaction time is 120 minutes, and it is measured by the method stipulated in the national standa...

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