WO2022245048A1 - System and method for manufacturing ckd-based carbon dioxide storage cement - Google Patents

Abstract

The present invention relates to a system for manufacturing CKD-based carbon dioxide storage cement, the system comprising: a material mixing apparatus for mixing clinker materials; a sintering apparatus for producing clinker by receiving and sintering the material from the material mixing apparatus; a cooling apparatus for receiving and cooling the clinker from the sintering apparatus; a pulverizing apparatus for manufacturing cement by receiving and pulverizing the clinker from the cooling apparatus; a kiln dust collection chamber for collecting and storing kiln dust produced during the pulverizing process in the pulverizing apparatus; and a captured carbon dioxide production chamber for producing captured carbon dioxide by reacting an exhaust gas produced from the sintering apparatus and the kiln dust supplied from the kiln dust collection chamber, and supplying the produced captured carbon dioxide to the clinker pulverizing apparatus.

Description

CKD-based carbon dioxide storage cement manufacturing system and method

The present invention produces carbon dioxide capture by-products by reacting with exhaust gases emitted from cement manufacturing facilities based on by-products generated during cement manufacturing, and manufacturing cement for permanent storage without carbon dioxide decarboxylation by mixing these by-products in the cement manufacturing step, pulverizing, and drying. It relates to a system and method for doing.

Since the early 19th century, industrialization has increased the concentration of greenhouse gases such as carbon dioxide (CO ₂ ), methane (CH ₄ ), hydrogen sulfide (H ₂ S), and carbonyl sulfide (COS) in the atmosphere, and is used in the modern energy industry. The use of fossil fuels, such as coal, petroleum, and liquefied natural gas, which are available, increases the concentration of carbon dioxide in the atmosphere and is pointed out as the biggest cause of global warming.

As global warming is accelerating due to an increase in greenhouse gases, regulations on emission and treatment are becoming stricter. Through the United Nations Conference on Environment and Development held in Rio, Brazil in June 1992, international interest in global warming is gradually increasing, and developed countries including the United States and Japan have agreed to reduce global greenhouse gas emissions by 5.2% in 2010 compared to 1990. An international agreement is being made on ways to reduce acid gas. In particular, the separation of carbon dioxide, which accounts for about 80% of greenhouse gases that cause global warming, has emerged as a more important issue.

Technologies for suppressing carbon dioxide emissions include energy saving technologies for reducing emissions, technologies for separating and recovering emitted carbon dioxide, technologies for using or fixing carbon dioxide, and new renewable energy technologies that do not emit carbon dioxide.

Among the carbon dioxide separation and recovery technologies studied so far, absorption, adsorption, membrane separation, and deep cooling are presented as realistic alternatives. In particular, since the absorption method is easy to process large-capacity gas and is suitable for separation of low-concentration gas, it is easily applicable to most industries and power plants, and is currently in commercial operation.

In addition, technologies for capturing and removing carbon dioxide from exhaust gas and reacting the absorbent with the exhaust gas to obtain carbon dioxide capture by-products such as calcium carbonate (CaCO ₃ ), which is an expensive raw material, have been developed.

However, these carbon dioxide capture by-products are limited in their use and are required to be applied to various fields, and in order to obtain and utilize the carbon dioxide capture by-products, separate dehydration, drying, and powdering processes are required, which increases manufacturing costs. There is a problem.

The basic concept of the cement manufacturing method and device using carbon dioxide is to saturate calcium hydroxide (Ca(OH) ₂ ) with water to produce a calcium hydroxide aqueous solution, and inject carbon dioxide (CO ₂ ) into the calcium hydroxide aqueous solution to cause a carbonation reaction to produce calcium carbonate (CaCO ₃ ) is produced, and cement is produced by applying a sol-gel method to silicon oxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), and calcium carbonate.

However, the cement manufactured by the cement manufacturing method and apparatus using the carbon dioxide trap has a problem in that the compressive strength is relatively reduced. In addition, the greenhouse gas issue has recently been raised and in line with the 2050 carbon neutralization in Korea, including the 2030 Tokyo Agreement, carbon dioxide reduction in the cement industry is recognized as a problem that must be solved.

Therefore, the present invention was invented to solve the above-mentioned problems of the prior art, and reacts the exhaust gas discharged from the cement manufacturing facility with the kiln dust generated during the cooling and grinding process of the clinker during cement manufacturing to generate carbon dioxide capture material. It is an object of the present invention to provide a system and method for manufacturing carbon dioxide permanent storage cement by injecting the produced carbon dioxide capture material into the cement manufacturing process.

As a means for solving the above problems, the CKD-based carbon dioxide storage cement manufacturing system according to the present invention (hereinafter referred to as "the system of the present invention") includes a raw material mixing device for mixing clinker raw materials; A firing device for generating clinker by firing raw materials supplied from the raw material mixing device; A cooling device that cools the clinker supplied from the firing device; A crushing device for receiving and pulverizing clinker from the cooling device to produce cement; A carbon dioxide capture material generating tank for generating a carbon dioxide capture material by reacting the exhaust gas generated from the firing device with the kiln dust supplied from the kiln dust collection tank and supplying the generated carbon dioxide capture material to the clinker grinding device; characterized by

As an example, in the kiln dust collection tank, kiln dust slurry is prepared by reacting water with kiln dust.

As an example, a filtering device is configured between the kiln dust collecting tank and the carbon dioxide collecting material generating tank, and an inlet line through which the kiln dust slurry flows is formed on one side of the filtering device to form a circulation in the introduced kiln dust slurry A housing in which a discharge line through which foreign matter having a high specific gravity is discharged is formed at the lower end, a discharge pipe through which the kiln dust slurry filtered through the upper surface of the housing is discharged upward to the carbon dioxide capture material generating tank, and the discharge pipe It is characterized in that it includes a filter port mounted on the bottom.

As an example, the filter includes a mounting ring mounted on the lower end of the discharge pipe, a filter unit having a flow hole formed at the end and a diameter narrowing toward the end, and a floating ring made of a floating material mounted on the flow hole. It is characterized by doing.

Meanwhile, the method for manufacturing CKD-based carbon dioxide storage cement of the present invention (hereinafter referred to as "the method of the present invention") includes mixing a clinker raw material (S10); Firing the raw material (S20); Cooling the calcined clinker (S30); Preparing cement by grinding the cooled clinker (S40); Collecting kiln dust generated in the grinding process (S50); A step of reacting the exhaust gas generated in step S20 with the kiln dust collected in step S50 to generate carbon dioxide capture material (S60); It is characterized in that it comprises a; step (S70) of adding the carbon dioxide collected in step S60 to the clinker crushing step (S40).

As described above, the present invention can permanently store carbon dioxide by using the exhaust gas and kiln dust discharged from the cement manufacturing facility to generate carbon dioxide capture material and reuse it in the cement manufacturing process to manufacture carbon dioxide storage cement, and industrial by-products There is an eco-friendly and economical advantage according to the reuse of

1 is a block diagram showing the system of the present invention;

2 is a block diagram illustrating the method of the present invention;

3 is a block diagram illustrating one embodiment of the present invention;

Figure 4 is a view showing an embodiment of the filtering device in Figure 3;

In describing the present invention, the terms or words used in this specification and claims are based on the principle that the inventor can appropriately define the concept of the term in order to best describe his or her invention. should be interpreted as a meaning and concept that corresponds to the technical idea of

As shown in FIG. 1, the system 1 of the present invention includes a raw material mixing device 2 for mixing clinker raw materials; A firing device (3) for generating clinker by firing raw materials supplied from the raw material mixing device (2); A cooling device (5) for receiving and cooling the clinker from the firing device (3); A grinding device (6) for receiving the clinker from the cooling device (5) and grinding it to produce cement; a kiln dust collection tank (7) for collecting and storing kiln dust generated in the grinding process in the grinding device (6); And by reacting the exhaust gas generated in the firing device 3 with the kiln dust supplied from the kiln dust collection tank 7 to generate carbon dioxide capture material and supplying the generated carbon dioxide capture material to the crushing device 6 It is characterized in that it comprises a; carbon dioxide capture material generating tank (8).

Among the above components, the raw material mixing device 2, the firing device 3, the cooling device 5, and the crushing device 6 are known components of the existing cement manufacturing system, and detailed description thereof will be omitted.

The kiln dust (CKD) collected in the kiln dust collection tank 7 is a by-product generated during the pulverization process in the pulverizer 6 and contains 30 to 45% of CaO. In the kiln dust collection tank 7, the collected kiln dust is reacted with water to produce a kiln dust slurry. It reacts with the exhaust gas to produce carbon dioxide traps.

That is, free CaO present in kiln dust reacts with water to produce Ca(OH) ₂ , and the generated Ca(OH) ₂ reacts with CO ₂ in exhaust gas to produce CaCO ₃ That is, to allow the production of carbon dioxide traps. The carbon dioxide collected in this way is added back to the raw material mixing device 2 to be recycled as a constituent material of cement.

Examples of the present invention will be described by means of experimental examples below.

In order to evaluate the usability of the CKD-based carbon dioxide storage cement produced by the system (1) of the present invention, the results of evaluating the compressive strength of the cement for the mixing ratio (% by weight) of the CKD-based carbon dioxide capture material in the cement manufacturing process are shown in Table 1 below. shown in

Subject name	CKD mixing ratio (% by weight)	28-day compressive strength (MPa)	Example/Control (%)
control group	0	43.1	-
Example 1	5	42.9	100
Example 2	10	40.5	94
Example 3	15	38.8	90
※ KS L ISO 679 was cited for the compressive strength test of cement.

As shown in Table 1, when the mixing ratio of the CKD-based carbon dioxide capture material was 5, 10, and 15% by weight, the 28-day compressive strength of the cement was 42.9, 40.5, and 38.8 MPa, respectively. It was evaluated as 100, 94, and 90%, respectively, compared to cement without water mixture). On the other hand, the kiln dust slurry generated in the kiln dust collection tank 7 is an eluate containing Ca and Mg, and Ca and Mg exist in an ionic state in the eluate, thereby providing conditions for reacting with carbon dioxide.

However, since the kiln dust slurry contains a large amount of impurities, there is a problem in that the production efficiency of the carbon dioxide capture material in the carbon dioxide capture material production tank 8 may decrease due to these impurities.

Accordingly, in the present invention, an example in which a filtration device 9 is further configured between the kiln dust collecting tank 7 and the carbon dioxide capture material generating tank 8 is suggested.

The filtering device 9 has an inlet line 911 through which kiln dust slurry flows in, a flow is formed in the kiln dust slurry introduced, and a discharge line 912 through which foreign substances filtered out by specific gravity are discharged at the lower end. A housing 91 passing through the upper surface of the housing 91, and a discharge pipe 92 through which the kiln dust slurry from which foreign substances are filtered is discharged upward to the carbon dioxide capture material generating tank 8, and the discharge pipe 92 It is characterized in that it includes a filter port mounted on the bottom.

The housing 91 is cylindrical, and the kiln dust slurry introduced therein circulates. The inlet line 911 is formed on one side of the housing 91, and it is preferable to be configured in a tangential direction of the housing 91. With this configuration, the kiln dust slurry introduced into the inlet line 911 circulates in the housing 91, thereby generating hydrocyclon and vortex. Centrifugal force is applied to the kiln dust slurry by the rotational motion of the fluid to achieve separation according to the specific gravity, and in the core formed by the vortex, a descending force acts, so that the separated foreign matter with a relatively small specific gravity moves from the core to the bottom. to let it come out.

In addition, the lower surface of the housing 91 is preferably formed with an inclined gradient so that the diameter becomes narrower toward the center, which facilitates the particles descending from the side wall of the housing 91 toward the discharge line 912 by the centrifugal force caused by the circulating flow. In addition to sliding smoothly, the flow rate increases as the diameter decreases to increase the swirl speed in the downward direction of the housing 91 so that the separated foreign substances can easily flow out into the discharge line 912 It is for

The discharge pipe 92 is formed through the upper surface of the housing 91, and as mentioned above, the kiln dust slurry from which foreign substances are filtered is discharged upward to the carbon dioxide capture material generating tank 8. Corresponds to a configuration do.

However, the kiln dust slurry discharged here is a state in which foreign substances having a specific gravity greater than or less than water are filtered out, and foreign substances having a specific gravity similar to water are included in the kiln dust slurry and discharged.

Accordingly, in the filtering device 9 of the present invention, a filter port mounted at the lower end of the discharge pipe 92 is configured so that foreign substances having a specific gravity similar to that of water are filtered out of the discharged kiln dust slurry. That is, the discharged kiln dust slurry is ionized water from which foreign substances are almost completely removed, and the production efficiency of the carbon dioxide capture material in the carbon dioxide capture material production tank 8 can be improved.

In particular, the filter port 93 includes a mounting ring 933 mounted on the lower end of the discharge pipe 92, a filter unit 931 having a diameter narrowing in the end direction and having a flow hole formed at the end, and the flow hole It is characterized in that it includes a floating ring 932 of floating material mounted on.

As shown in the figure, the mounting ring 933 is mounted on the lower end of the discharge pipe 92 inside the housing 91, and the filter port 93 is mounted on the discharge pipe 92. The filter unit 931 is configured to filter foreign substances from the upward kiln dust slurry by forming a gap, and for this purpose, the filter unit 931 is configured in a shape in which the diameter becomes narrower toward the end, and a flow hole is formed at the end to filter kiln dust slurry is to be discharged to the outside of the discharge pipe 92 through a fluid hole, and the reason why the fluid hole is formed is to ensure smooth upward flow of the fluid during the filtration process to enable smooth operation of the entire device.

When the upward flow of the fluid is controlled, the circulating flow in the housing 91 is not smoothly formed, and as mentioned above, the filtering efficiency of foreign substances by the centrifugal force is reduced. In this embodiment, the filter unit having the above structure 931 is configured to increase the filtration efficiency of the entire device by controlling the upward flow of the fluid to a minimum at the same time as the filtration.

The material of the filter unit 931 is not limited.

The floating ring 932 is a floating material attached to the flow hole. The reason why the floating ring 932 is configured in this way is that when the device is not operating, the filter hole maintains a downwardly stretched state, and when the device is operating, the fluid While the floating ring 932 floats in the discharge pipe 92 by the upward flow, the floating hole is positioned upward.

Accordingly, the upstream flows upward while in contact with the filter unit 931 so that the filtration is performed and the filtered upstream is discharged to the discharge pipe 92 through the flow hole. That is, when the device is operated by the floating ring 932, the filter port can be positioned so that filtration and discharge can be easily performed in the discharge pipe 92.

Referring to the operating relationship of this embodiment, since the inlet line 911 is configured in the tangential direction of the housing 91, water obtained through the inlet line 911 naturally forms a circular flow without any power. The moving path of the particles having a specific gravity greater than that of water is moved to the sidewall of the housing 91 by centrifugal force, and flows out to the discharge line 912 along the lower surface of the housing 91.

In addition, the circulation formed in the housing 91 generates a vortex, and at the center of this vortex, a core portion rotating at a speed of twice or more than the tangential flow rate is generated. Although this core is not shown in the drawing, the discharge pipe ( 92) and the discharge line 912, and is a part where strong suction power is generated in the downward direction. Therefore, in the case of the movement path of the foreign matter having a specific gravity smaller than water, it moves toward the center by the centripetal force, opposite to the moving path of the foreign matter having a specific gravity greater than water, eventually reaching the core and flowing out to the discharge line 912 by the downward suction force. .

In addition, the movement path of foreign matter having a specific gravity similar to that of water and oil that is not separated by centrifugal force moves according to the flow of water. ), while the floating ring 932 floats due to the upward flow, the filter port is positioned inside the discharge pipe 92 in a mountain shape. Accordingly, the upward flow is directed upward while in contact with the filter unit 931, so that foreign substances having a specific gravity similar to water and oil not separated by the centrifugal force are filtered in the filter unit 931, and the filtered upflow is a flow hole It is to be discharged to the discharge pipe (92) through.

Meanwhile, as shown in FIG. 2, the method of the present invention includes mixing clinker raw materials (S10); Firing the raw material (S20); Cooling the calcined clinker (S30); Preparing cement by grinding the cooled clinker (S40); Collecting kiln dust generated in the grinding process (S50); A step of reacting the exhaust gas generated in step S20 with the kiln dust collected in step S50 to generate carbon dioxide capture material (S60); and adding the carbon dioxide collected in step S60 to the clinker crushing step (S40) (S70).

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also made according to the present invention. falls within the scope of the rights of

Claims (5)

1. Raw material mixing device for mixing clinker raw materials;

   A firing device for generating clinker by firing raw materials supplied from the raw material mixing device;

   A cooling device that cools the clinker supplied from the firing device;

   A crushing device for receiving and pulverizing clinker from the cooling device to produce cement;

   a kiln dust collection tank for collecting and storing kiln dust generated during the grinding process in the grinding device; and

   A carbon dioxide capture material generating tank for generating a carbon dioxide capture material by reacting the exhaust gas generated from the firing device with the kiln dust supplied from the kiln dust collection tank and supplying the generated carbon dioxide capture material to the clinker grinding device; CKD-based carbon dioxide storage cement manufacturing system, characterized in that.
2. According to claim 1,

   CKD-based carbon dioxide storage cement manufacturing system, characterized in that the kiln dust slurry is prepared by reacting water with kiln dust in the kiln dust collection tank.
3. According to claim 2,

   A filtering device is configured between the kiln dust collection tank and the carbon dioxide capture material generating tank,

   The filter device is

   A housing in which an inlet line into which kiln dust slurry flows is formed on one side, a circulation is formed in the introduced kiln dust slurry, and a discharge line through which foreign substances are discharged is formed at the lower end, and the kiln dust slurry penetrating the upper surface of the housing and filtering foreign substances is CKD-based carbon dioxide storage cement manufacturing system, characterized in that it comprises a discharge pipe to be discharged upward to the carbon dioxide capture material generating tank, and a filter port mounted on the lower end of the discharge pipe.
4. According to claim 3,

   The filter is characterized in that it includes a mounting ring mounted on the lower end of the discharge pipe, a filter unit having a flow hole formed at the end and a diameter narrowing in the end direction, and a floating ring made of a floating material mounted on the flow hole. CKD-based carbon dioxide storage cement manufacturing system.
5. Mixing clinker raw materials (S10);

   Firing the raw material (S20);

   Cooling the calcined clinker (S30);

   Preparing cement by grinding the cooled clinker (S40);

   Collecting kiln dust generated in the grinding process (S50);

   A step of reacting the exhaust gas generated in step S20 with the kiln dust collected in step S50 to generate carbon dioxide capture material (S60); and

   CKD-based carbon dioxide storage cement manufacturing method comprising the step (S70) of adding the carbon dioxide collected in step S60 to the clinker grinding step (S40).

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