CN116903018A - Calcium carbonate precipitation and production process thereof - Google Patents

Abstract

The invention discloses a calcium carbonate precipitate and a production process thereof, relates to the technical field of calcium carbonate precipitates, shortens the production time of the calcium carbonate precipitate with lower cost, and improves the yield of the calcium carbonate precipitate. The production process comprises the following steps: in a carbonator, carrying out carbonation reaction on carbon dioxide and first calcium hydroxide slurry to obtain a first product; the dosage of the first calcium hydroxide slurry is 35m ³ ～50m ³ The method comprises the steps of carrying out a first treatment on the surface of the Supplementing the second calcium hydroxide slurry into a carbonator for carbonation reaction under the action of the carbon dioxide to obtain a second product; the dosage of the second calcium hydroxide slurry is 9m ³ ～13m ³ The method comprises the steps of carrying out a first treatment on the surface of the Mixing the first product with the second product to obtain a calcium carbonate precipitate.

Description

Calcium carbonate precipitation and production process thereof

Technical field

The invention relates to the technical field of carbonators, and in particular to a calcium carbonate precipitation and its production process.

Background technique

In the production process of calcium carbonate, due to the small amount of calcium hydroxide slurry passed into the carbonator filling port, the liquid level formed in the carbonator is low, causing the carbon dioxide and hydroxide in the carbonator to The contact time of calcium slurry is short, which not only results in low productivity, but also causes waste of carbon dioxide. In addition, the calcium hydroxide slurry will be replenished into the carbonator multiple times, a process that requires a lot of time and electricity.

Contents of the invention

The object of the present invention is to provide a calcium carbonate precipitation and its production process, which can shorten the production time of calcium carbonate precipitation and increase the output of calcium carbonate precipitation at a lower cost.

In a first aspect, in order to achieve the above object, the present invention provides a production process for calcium carbonate precipitation, which process is applied to a carbonator and includes:

In the carbonator, carbon dioxide is used to perform a carbonation reaction with the first calcium hydroxide slurry to obtain the first product; the amount of the first calcium hydroxide slurry is 35m ³ to 45m ³ ;

Under the action of the carbon dioxide, the second calcium hydroxide slurry is added to the carbonator to perform a carbonation reaction to obtain a second product; the amount of the second calcium hydroxide slurry is 9m ³ to 13m ³ ;

The first product is mixed with the second product to obtain calcium carbonate precipitation.

Compared with the prior art, in the production process of calcium carbonate precipitation provided by the present invention, the first calcium hydroxide slurry in an amount of 35m ³ to 45m ³ is passed into a carbonator containing carbon dioxide, so that the first hydroxide is oxidized Calcium slurry has a higher liquid level in the carbonator. At this time, the residence time of carbon dioxide in the first calcium hydroxide slurry is relatively long, allowing the two to fully react. Especially when the amount of the first calcium hydroxide slurry is 35m ³ to 45m ³ , the utilization rate of carbon dioxide is It is higher, thereby shortening the production time of calcium carbonate precipitation and increasing the yield of the first product. Next, under the action of carbon dioxide, a second calcium hydroxide slurry in an amount of 9m ³ to 13m ³ is added to the carbonator to perform a carbonation reaction to obtain a second product. Different from the prior art in which the second calcium hydroxide slurry is replenished into the carbonator multiple times, the production process used in the present invention is to reduce the number of replenishments of the second calcium hydroxide to one time and limit the replenishment amount. It is 9m ³ ~ 13m ³ . At this time, the consumption of carbon dioxide and electricity consumption of supplementary devices can be reduced, thereby reducing the production cost and further shortening the production time of calcium carbonate precipitation.

In a second aspect, the present invention also provides calcium carbonate precipitation produced by the above-mentioned calcium carbonate precipitation production process.

Compared with the prior art, the beneficial effects of the calcium carbonate precipitation provided by the present invention are the same as the beneficial effects of the first aspect of the production process of calcium carbonate precipitation, and will not be described again here.

Description of the drawings

The drawings described here are used to provide a further understanding of the present invention and constitute a part of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the attached picture:

Figure 1 shows a flow chart of the production process of calcium carbonate precipitation provided by the embodiment of the present invention;

Figure 2 shows a schematic structural diagram of a carbonator used in an embodiment of the present invention.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, "plurality" means two or more than two, unless otherwise explicitly and specifically limited. "Several" means one or more than one, unless otherwise expressly and specifically limited.

In the production process of calcium carbonate, due to the small amount of calcium hydroxide slurry passed into the carbonator filling port, the liquid level formed in the carbonator is low, causing the carbon dioxide and hydroxide in the carbonator to The contact time of calcium slurry is short, which not only results in low productivity, but also causes waste of carbon dioxide. In addition, the calcium hydroxide slurry will be replenished into the carbonator multiple times, a process that requires a lot of time and electricity.

In response to the above problems, embodiments of the present invention provide a production process for calcium carbonate precipitation, which can shorten the production time of calcium carbonate precipitation and increase the output of calcium carbonate precipitation at a lower cost. Figure 1 shows a flow chart of the production process of calcium carbonate precipitation provided by the embodiment of the present invention. As shown in Figure 1, the production process of calcium carbonate precipitation includes:

Step 101: In a carbonator, use carbon dioxide and the first calcium hydroxide slurry to perform a carbonation reaction to obtain the first product; the amount of the first calcium hydroxide slurry is 35m ³ to 45m ³ .

Illustratively, the embodiment of the present invention increases the liquid level of the slurry in the carbonator by setting the amount of the first calcium hydroxide slurry. At this time, the residence time of carbon dioxide in the first calcium hydroxide slurry is relatively long, allowing the two to fully react. Especially when the amount of the first calcium hydroxide slurry is 35m ³ to 45m ³ , the utilization rate of carbon dioxide is It is higher, thereby shortening the production time of calcium carbonate precipitation and increasing the yield of the first product.

For example, the solid content of the first calcium hydroxide slurry used in the embodiment of the present invention is 18%, and the carbon dioxide is excess carbon dioxide. The usage amount of the first calcium hydroxide slurry is preferably 41m ³ to 45m ³ .

Figure 2 shows a schematic structural diagram of a carbonator used in an embodiment of the present invention. As shown in Figure 2, the carbonator 200 includes a multi-layer orifice plate 201, which is used to cut the carbon dioxide into small carbon dioxide bubbles to increase the contact probability between the carbon dioxide and the slurry, so that the carbon dioxide and the first The calcium hydroxide slurry is fully contacted and reacted to generate the first product, that is, the first calcium carbonate precipitate.

Step 102: Under the action of carbon dioxide, add the second calcium hydroxide slurry to the carbonator for carbonation reaction to obtain the second product; the amount of the second calcium hydroxide slurry is 9m ³ to 13m ³ .

Illustratively, unlike the prior art in which the second calcium hydroxide slurry is added to the carbonator multiple times, the production process used in the present invention is to reduce the number of times of adding the second calcium hydroxide to one, and The replenishment amount is limited to 9m ³ ~ 13m ³ . At this time, the carbon dioxide consumption and electricity consumption of the replenishment device can be reduced, thereby reducing the production cost and further shortening the production time of calcium carbonate precipitation.

For example, the amount of the second calcium hydroxide slurry is preferably 11 m ³ to 13 m ³ , and the concentration of the second calcium hydroxide slurry is mol/L.

For example, as shown in Figure 2, the carbonator 200 includes a main filling port 202 and a secondary filling port 203, wherein the first calcium hydroxide slurry flows into the carbonator 200 through the main filling port 202. The second calcium hydroxide slurry flows into the carbonator 200 through the secondary filling port 203.

In practical applications, 35m ³ to 45m ³ of the first calcium hydroxide slurry is first flowed into the carbonator through the main filling port, and the first product is generated under the action of carbon dioxide, and then 9m ³ to 13m ³ of the second calcium hydroxide slurry is flowed into the carbonator. Calcium hydroxide slurry is replenished into the carbonator through the auxiliary filling port for carbonation reaction to obtain the second product.

Exemplarily, as shown in Figure 2, the carbonator 200 includes an air inlet 204 and an air outlet 205. Carbon dioxide enters the carbonator 200 through the air inlet, and is divided into small bubbles through the multi-layer orifice plate 201, and reacts The exhaust gas produced after completion is discharged from the air outlet.

Step 103: Mix the first product and the second product to obtain calcium carbonate precipitation.

Exemplarily, the time for producing calcium carbonate precipitation is 124min-130min, preferably 124min-126min.

Embodiments of the present invention also provide calcium carbonate precipitation produced by the above-mentioned calcium carbonate precipitation production process. The calcium carbonate precipitation has a short production time, low energy consumption, and an annual output increase of 28,000 tons.

In order to verify the production process of calcium carbonate precipitation provided by the embodiments of the present invention, the embodiments of the present invention are explained using examples and comparative examples.

Embodiment 1

The first step is to generate the first product: pass 35 m ³ of the first calcium hydroxide slurry into the carbonator, and react it with excess carbon dioxide in the carbonator to obtain the first product.

In the second step, the second product is generated: under the action of carbon dioxide, 9m3 of the second calcium hydroxide slurry is added to the carbonator to perform a carbonation reaction to obtain the second product.

The third step is to generate calcium carbonate precipitation: mix the first product and the second product, and collect the calcium carbonate precipitation from the carbonator. The entire production process lasts 124 minutes, and the output of calcium carbonate precipitation is 158,000 tons/year. . When the calcium carbonate precipitation produced by this process is used in three paper machines to produce paper, 860,000 kWh of electricity and 36,000 tons of water are saved every year.

Embodiment 2

The first step is to generate the first product: pass 45 m ³ of the first calcium hydroxide slurry into the carbonator, and react it with excess carbon dioxide in the carbonator to obtain the first product.

In the second step, the second product is generated: under the action of carbon dioxide, 13 m ³ of the second calcium hydroxide slurry is added to the carbonator to perform a carbonation reaction to obtain the second product.

The third step is to generate calcium carbonate precipitation: mix the first product and the second product, and collect the calcium carbonate precipitation from the carbonator. The entire production process lasts 130 minutes, and the output of calcium carbonate precipitation is 149,000 tons/year. . When the calcium carbonate precipitation produced by this process is used in three paper machines to produce paper, 645,000 kWh of electricity and 27,000 tons of water are saved every year.

Embodiment 3

The first step is to generate the first product: pass 41m ³ of the first calcium hydroxide slurry into the carbonator, and react it with excess carbon dioxide in the carbonator to obtain the first product.

In the second step, the second product is generated: under the action of carbon dioxide, 11 m ³ of the second calcium hydroxide slurry is added to the carbonator to perform a carbonation reaction to obtain the second product.

The third step is to generate calcium carbonate precipitation: mix the first product and the second product, and collect the calcium carbonate precipitation from the carbonator. The entire production process lasts 126 minutes, and the output of calcium carbonate precipitation is 151,000 tons/year. . When the calcium carbonate precipitation produced by this process is used in three paper machines to produce paper, 788,000 kWh of electricity and 33,000 tons of water are saved every year.

Comparative Example 1

Step 1: Pour 25 m ³ of the first calcium hydroxide slurry into the carbonator to react with excess carbon dioxide in the carbonator to form calcium carbonate precipitation.

Step 2: Under the action of carbon dioxide, add 10m ³ of the second calcium hydroxide slurry to the carbonator for carbonation reaction. After the reaction is completed, add 5m ³ of the second calcium hydroxide slurry to the carbonator. The carbonation reaction is carried out in the carbonator. After the complete reaction, 4 m ³ of the second calcium hydroxide slurry is finally added to the carbonator for carbonation reaction to generate calcium carbonate precipitation.

Step 3: Collect the above-mentioned calcium carbonate precipitation from the carbonator. The entire production process lasts 148 minutes, and the output of calcium carbonate precipitation is 130,000 tons/year. The output of calcium carbonate precipitation produced by this process was not sufficient to produce paper on three paper machines.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present invention. should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (9)

1. A process for the production of calcium carbonate precipitate, characterized in that it is applied to a carbonator, comprising:

in a carbonator, carrying out carbonation reaction on carbon dioxide and first calcium hydroxide slurry to obtain a first product; the dosage of the first calcium hydroxide slurry is 35m ³ ～45m ³ ；

Supplementing the second calcium hydroxide slurry into a carbonator for carbonation reaction under the action of the carbon dioxide to obtain a second product; the dosage of the second calcium hydroxide slurry is 9m ³ ～13m ³ ；

Mixing the first product with the second product to obtain a calcium carbonate precipitate.

2. The process for producing calcium carbonate precipitate according to claim 1, wherein the time for producing the calcium carbonate precipitate is 124min to 130min.

3. The process for producing calcium carbonate precipitation according to claim 1, wherein the first calcium hydroxide slurry has a solids content of 18%, the second calcium hydroxide slurry has a solids content of 18%, and the carbon dioxide is excess carbon dioxide.

4. The process for producing calcium carbonate precipitate according to claim 1, wherein the carbonator comprises a multi-layer orifice plate for cutting the carbon dioxide into carbon dioxide small bubbles.

5. The process for producing calcium carbonate precipitation according to claim 1, wherein the carbonator comprises a primary filler port and a secondary filler port, the first calcium hydroxide slurry flowing into the carbonator through the primary filler port; the second calcium hydroxide slurry flows into the carbonator through the secondary fill port.

6. The process for the production of calcium carbonate precipitates according to claim 1, wherein said carbonator comprises an air inlet and an air outlet for discharging the tail gas generated during the reaction; the carbon dioxide enters the carbonator through an air inlet.

7. The process for producing calcium carbonate precipitate according to claim 1, wherein the first calcium hydroxide slurry is used in an amount of 41m ³ ～50m ³ The method comprises the steps of carrying out a first treatment on the surface of the The dosage of the second calcium hydroxide slurry is 11m ³ ～13m ³ 。

8. The process for producing calcium carbonate precipitate according to claim 2, wherein the time for producing the calcium carbonate precipitate is 124min to 126min.

9. A calcium carbonate precipitate produced by the production process of a calcium carbonate precipitate according to any one of claims 1 to 8.