Method for producing calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite using fishery byproducts

Abstract

The present invention relates to a method for producing high-purity calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite using fishery byproducts. More particularly, the present invention relates to a continuous producing method in which: when sodium carbonate (Na2CO3) reacts with slaked lime (calcium hydroxide, Ca(OH)2)), calcium carbonate is formed and wastewater containing caustic soda (NaOH) is generated; in order to recycle the wastewater, fishery byproducts are dissolved in water diluted with hydrochloric acid, followed by removal of impurities, and the wastewater containing caustic soda is then added to provide OH-(hydroxyl ions), whereby chloride ions present in the fishery byproducts dissolved in dilute hydrochloric acid are substituted with OH-(hydroxyl ions), thereby completing slaked lime and liquid slaked lime; and the wastewater remaining after the production of slaked lime is subjected to electrolysis to produce a sodium hypochlorite (NaOCl) solution.

Description

Method for manufacturing calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite using marine by-products

[0001] The present invention relates to a method for manufacturing high-purity calcium carbonate, slaked lime, liquid slaked lime and sodium hypochlorite in a continuous process using marine by-products.

[0002] Domestically and internationally, slaked lime and liquid slaked lime (Ca(OH)2) are widely used as neutralizing agents in industrial fields such as water treatment, air emission treatment, and deodorization, and as very useful substances for treating acids such as fluorine and sulfur.

[0003] The current method of manufacturing slaked lime and liquid slaked lime is to calcinate mineral calcium carbonate such as limestone at a temperature of 900 to 1200°C to obtain calcium oxide, which is then hydrated with water to obtain slaked lime and liquid slaked lime.

[0004] Related conventional technologies, such as Korean Patent No. 10-1297989, Korean Patent Publication Nos. 10-1999-0085149, and 10-2019-0059472, provide methods for producing hydrated lime powder by calcining quicklime and oyster shells at high temperatures. However, this method inherently requires a calcination process, which poses environmental and economic challenges related to fuel usage and carbon dioxide emissions.

[0005] Korean Patent Publication No. 10-2020-0110882 discloses a method for producing liquid slaked lime by calcining oyster shells, a byproduct of the marine industry, at high temperatures and then hydrating them with water. Furthermore, Korean Patent Registration No. 10-1095879, Korean Patent Publication No. 10-1996-0000773, and Korean Patent Publication No. 10-2013-00299969 disclose methods for producing liquid slaked lime by calcining limestone at high temperatures and then hydrating it with water. However, these methods also require a basic calcination process, which poses environmental and economic concerns regarding fuel consumption and carbon dioxide emissions.

[0006] Furthermore, existing liquid slaked lime has large particles, which results in poor dispersibility and poor flow within the solution, leading to frequent pipe clogging and pump failure. Therefore, efforts are being made to further reduce the particle size. Republic of Korea Utility Model No. 20-0492037 and Korean Patent No. 10-1297988 propose methods for further reducing particle size or increasing specific surface area by adding chemical additives or performing wet grinding during the production of liquid slaked lime. However, this method has limitations in grinding, making it difficult to obtain smaller particles and a narrow particle size distribution, and there are problems with mass production due to the additional process.

[0007] In addition, in order to manufacture caustic soda (NaOH), Korean Patent Registration No. 10-0363012 discloses a method of manufacturing caustic soda through electrolysis in an electrolytic cell with a cation chamber and an anion chamber separated by a membrane using salt water, but there are problems with excessive power consumption and complicated equipment, and Korean Patent Publication No. 10-2010-0026020 utilizes an ammonia soda method of manufacturing caustic soda by reacting soda ash (Na2CO3) with calcium hydroxide (Ca(OH)2), but the purity of calcium hydroxide (Ca(OH)2) is low, so the production ratio of calcium carbonate (CaCO3) is low, and accordingly, the amount of unreacted soda ash is large, so the quality of the final caustic soda is poor, and to improve this, an iron salt catalyst is used at a temperature of 55℃ to 75℃ to promote causticization, and there are problems with the additional use of unnecessary raw materials.

[0008] Accordingly, there is a need for a technology to easily and environmentally friendly manufacture slaked lime powder and liquid slaked lime without going through a calcination process.

[0009] Accordingly, the present invention was conducted while researching to overcome the problems of manufacturing existing slaked lime and liquid slaked lime, and it was confirmed that it is possible to manufacture calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite at once by electrolyzing wastewater in an environmentally friendly and simple manner without a calcination process. The present invention relates to a method for manufacturing high-purity calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite using marine by-products, and more specifically, when sodium carbonate (Na2CO3) and slaked lime (calcium hydroxide, Ca(OH)2)) are reacted, calcium carbonate is formed and wastewater is formed of caustic soda (NaOH), and in order to recycle this wastewater, marine by-products are dissolved in water diluted with hydrochloric acid, impurities are removed, and wastewater composed of the above caustic soda is added to the solution to form OH - (hydroxyl group) is provided to convert the chloride ion of the oxalic acid by-product dissolved in dilute hydrochloric acid into OH -By replacing (hydroxyl groups) with hydrated lime, slaked lime and liquid slaked lime were obtained and completed. In addition, the wastewater remaining after slaked lime production is composed of sodium chloride (NaCl), so it was confirmed that the wastewater can be fully recycled by electrolyzing it to create a sodium hypochlorite (NaOCl) solution and recycling it as a sterilizing disinfectant.

[0010] The purpose of the present invention is to provide a method for manufacturing calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite at once by electrolyzing wastewater in an environmentally friendly manner using marine by-products without going through a calcination process.

[0011] In order to achieve the above purpose, the present invention comprises the steps of 1) forming calcium carbonate by reacting sodium carbonate (Na2CO3) and slaked lime (Ca(OH)2)) in water under solution; 2) separating calcium carbonate from the solution; 3) dissolving a maritime by-product in water diluted with hydrochloric acid to obtain a calcium chloride (CaCl2) solution, and adding the solution of step 2) to it with OH - The present invention provides a continuous manufacturing method for calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite, characterized by including: a step of completing slaked lime and liquid slaked lime by adding (hydroxyl group) to provide; 4) a step of separating slaked lime (Ca(OH)2) from a solution; and 5) a step of making a sodium hypochlorite (NaOCl) solution through electrolysis to recycle the wastewater generated in step 4.

[0012] For example, the present invention provides a continuous manufacturing method in which the ratio of sodium carbonate (Na2CO3) and slaked lime (Ca(OH)2)) in step 1) is 0.8 to 1.2 based on sodium carbonate.

[0013] In the above step 3) of the present invention, the aquatic by-product may additionally include at least one selected from the group of calcium-providing raw materials consisting of calcium carbonate, calcium oxide, calcium chloride, and calcium hydroxide, and may be manufactured solely with aquatic by-products. Here, the aquatic by-products include waste by-products containing calcium components, such as shells of oysters, clams, Manila clams, cockles, abalone, and starfish.

[0014] For example, the present invention provides a continuous manufacturing method for dissolving the above-mentioned aquatic by-product with water and hydrochloric acid to form calcium chloride, wherein the amount of water in which hydrochloric acid is diluted is preferably 10 to 30 wt%, and more preferably 12 to 25 wt%.

[0015] In addition, the present invention provides a manufacturing method including a step of recycling carbon dioxide generated when dissolving a marine by-product in hydrochloric acid in step 3) by introducing it into step 1), thereby minimizing the emission of by-products generated in a continuous manufacturing method and providing an environmentally friendly method.

[0016] In addition, the present invention provides a continuous manufacturing method characterized in that the slaked lime and liquid slaked lime completed in the above step 3) are manufactured by replacing chlorine with hydroxyl groups through a liquid process without going through a heat treatment and calcination process.

[0017] In addition, the present invention may further include a process of individually packaging each material so that calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite manufactured by the above manufacturing method can be used as food additives, health functional foods, fluoride removers, sulfur removers, odor removers, acid gas treatment agents, neutralizers, cement, sterilizers, and disinfectants.

[0018] As another example, the present invention provides a method for using the solution separated in step 2) as a raw material for paper, fiber, detergent, soap, food, metal, electricity, wastewater treatment, or carbon dioxide absorbent, comprising the steps of 1) forming calcium carbonate by reacting sodium carbonate (Na2CO3) and slaked lime (Ca(OH)2)) in water in a solution; and 2) separating the calcium carbonate from the solution.

[0019] According to the present invention, calcium carbonate is formed by reacting sodium carbonate (Na2CO3) and slaked lime (calcium hydroxide, Ca(OH)2)). Through this, it is possible to manufacture calcium carbonate having a particle size of less than 2 μm and a spherical shape. When calcium carbonate and the solution are separated, the separated solution is composed of caustic soda (NaOH), and in order to manufacture slaked lime and liquid slaked lime by dissolving a by-product of an oxalic acid in water diluted with hydrochloric acid to obtain a CaCl2 solution, and adding OH to this solution. - To provide (hydroxyl groups), wastewater consisting of caustic soda (NaOH) is recycled to convert chloride ions of oxalic acid by-products dissolved in dilute hydrochloric acid into OH - (hydroxyl group) is substituted to form slaked lime (Ca(OH)2). Through this, it is possible to manufacture slaked lime and liquid slaked lime with a particle size of about 3 μm (2,000 to 5,000 mesh), so that it is possible to manufacture slaked lime and liquid slaked lime that have good flowability of liquid slaked lime solution and reduce pipe clogging. In addition, the slaked lime (Ca(OH)2) is separated from the solution, and sodium hypochlorite is obtained by electrolyzing the NaCl solution contained in the separated wastewater, which can be recycled as a sterilizing disinfectant, thereby providing a simple and environmentally friendly method for manufacturing calcium carbonate, slaked lime, liquid slaked lime and sodium hypochlorite.

[0020] Additionally, it is environmentally friendly and much more economical in terms of manufacturing costs as it does not require a firing process compared to existing methods.

[0021] Figure 1 is a process diagram for manufacturing calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite of the present invention.

[0022] Figure 2 shows the crystal structure according to the X-ray diffraction analysis results of calcium carbonate and calcium hydroxide manufactured according to Examples 1 and 2.

[0023] Figure 3 shows the particle size distribution of calcium carbonate and calcium hydroxide manufactured according to Example 1, Example 2, and Comparative Example 1.

[0024] The present invention relates to a method for producing calcium carbonate, slaked lime, liquid slaked lime and sodium hypochlorite in a single process without a calcination process, and to an environmentally friendly method for recycling wastewater. More specifically, when sodium carbonate (Na2CO3) and slaked lime (calcium hydroxide, Ca(OH)2)) are reacted, calcium carbonate is formed and wastewater is composed of caustic soda (NaOH). In order to recycle this wastewater, the slaked lime is dissolved in water diluted with hydrochloric acid, impurities are removed, and wastewater composed of the caustic soda is added to the solution to produce OH. - (hydroxyl group) is provided to convert the chloride ion of the oxalic acid by-product dissolved in dilute hydrochloric acid into OH - (hydroxyl group) to complete slaked lime and liquid slaked lime. In addition, the wastewater remaining after slaked lime is manufactured is composed of sodium chloride (NaCl), which is electrolyzed to create a sodium hypochlorite (NaOCl) solution and used as a sterilizing disinfectant. This method for manufacturing calcium carbonate, slaked lime, liquid slaked lime and sodium hypochlorite is different from the existing method of manufacturing slaked lime and liquid slaked lime by calcining marine by-products at a temperature of 900℃ or higher to produce calcium oxide and then hydrating it with water, as it does not require a high-temperature calcination process, so there is no problem of carbon dioxide emission, and the process is simple and can manufacture calcium carbonate, slaked lime, liquid slaked lime and sodium hypochlorite in one process, and it relates to a continuous manufacturing method with high industrial economic value and an environmentally friendly process with minimal pollutants.

[0025]

[0026] The present invention is described in detail below.

[0027] The present invention relates to a method for producing high-purity calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite in a single continuous process by utilizing aquatic by-products. More specifically, when sodium carbonate (Na2CO3) and slaked lime (calcium hydroxide, Ca(OH)2)) are reacted, calcium carbonate is formed and wastewater is composed of caustic soda (NaOH). In order to recycle this wastewater, aquatic by-products are dissolved in water in which hydrochloric acid is diluted, impurities are removed, and the wastewater composed of the caustic soda is added to the solution to produce OH. - (hydroxyl group) is provided to convert the chloride ion of the oxalic acid by-product dissolved in dilute hydrochloric acid into OH - (Hydrolysis) is used to complete the production of slaked lime and liquid slaked lime, and the wastewater remaining after the slaked lime is produced is composed of sodium chloride (NaCl), which can be electrolyzed to create a sodium hypochlorite (NaOCl) solution and recycled as a sterilizing disinfectant.

[0028] According to the present invention, calcium carbonate is formed by reacting sodium carbonate (Na2CO3) and slaked lime (calcium hydroxide, Ca(OH)2)). Through this, it is possible to manufacture calcium carbonate having a high purity of 99% or more, a particle size of less than 2 μm, and a spherical shape. When calcium carbonate and the solution are separated, the separated solution consists of caustic soda (NaOH), which can be used to manufacture slaked lime and liquid slaked lime. A CaCl2 solution is obtained by dissolving a by-product of aquatic products in water diluted with hydrochloric acid, and OH is added to this solution. - In order to provide (hydroxyl group), the wastewater composed of the above caustic soda (NaOH) is recycled to convert the chloride ion of the oxalic acid by-product dissolved in dilute hydrochloric acid into OH -(hydroxyl group) is substituted to form slaked lime (Ca(OH)2). Through this, it is possible to manufacture slaked lime and liquid slaked lime with a high purity of 98.5% or more and a particle size of about 3 μm (2,000 to 5,000 mesh), so that it is possible to manufacture slaked lime and liquid slaked lime with good flowability of the liquid slaked lime solution and reduce pipe clogging. In addition, the slaked lime (Ca(OH)2) is separated from the solution, and sodium hypochlorite is obtained by electrolyzing the NaCl solution contained in the separated wastewater, which can be recycled as a sterilizing disinfectant, thereby providing a simple and environmentally friendly method for manufacturing calcium carbonate, slaked lime, liquid slaked lime and sodium hypochlorite.

[0029] This method for manufacturing calcium carbonate, slaked lime, liquid slaked lime and sodium hypochlorite is different from the existing method of manufacturing calcium oxide by calcining marine by-products at a temperature of 900℃ or higher and then manufacturing liquid slaked lime by hydrating it with water, as it does not require a high-temperature calcination process, so there is no problem of carbon dioxide emissions and the process is simple, making it good for the environment and the economy.

[0030] Also, when sodium carbonate (Na2CO3) and slaked lime (calcium hydroxide, Ca(OH)2)) are reacted, calcium carbonate is formed. If the carbon dioxide generated when oyster shells are dissolved is recycled in this process, the amount of sodium carbonate (Na2CO3) raw material used can be saved by more than 10%, and the carbon dioxide can also be completely recycled, which is good both economically and environmentally.

[0031]

[0032] Figure 1 is a process diagram for manufacturing calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite of the present invention.

[0033]

[0034] The present invention comprises the steps of: 1) forming calcium carbonate by reacting sodium carbonate (Na2CO3) and slaked lime (Ca(OH)2)) in a solution in water; 2) separating calcium carbonate from the solution; 3) dissolving a maritime by-product in water diluted with hydrochloric acid to obtain a calcium chloride (CaCl2) solution, and adding the solution of step 2) to it with OH - The present invention provides a continuous manufacturing method for calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite, characterized by including: a step of completing slaked lime and liquid slaked lime by adding (hydroxyl group) to provide; 4) a step of separating slaked lime (Ca(OH)2) from a solution; and 5) a step of making a sodium hypochlorite (NaOCl) solution through electrolysis to recycle the wastewater generated in step 4.

[0035]

[0036] The molar ratio of sodium carbonate (Na2CO3) and slaked lime (calcium hydroxide, Ca(OH)2)) in the above step 1) is preferably 1:1.

[0037] If the ratio is less than 1:1, there is a problem that the yield of calcium carbonate is low or unreacted calcium hydroxide remains, lowering the purity of calcium carbonate. If the ratio is more than 1:1, it is not economical due to the use of excessive sodium carbonate (Na2CO3).

[0038]

[0039] The separation of calcium carbonate and solution in step 2) above can be accomplished using a filter press or centrifuge.

[0040]

[0041] In order to dissolve the aquatic by-products in step 3), it is preferable that the mixing ratio of hydrochloric acid to water be 10% to 30% by weight or less.

[0042] Specifically, the ratio of water and hydrochloric acid in step 1 may be mixed within 10% to 30% by weight, and preferably within 12% to 25% by weight.

[0043] If the ratio of water to hydrochloric acid is less than 10% by weight, there is a problem that the amount of dissolved aquatic by-products decreases, resulting in an increase in waste residue, or the amount of dissolved calcium decreases, resulting in a decrease in the concentration of calcium in the solution. If the ratio of water to hydrochloric acid is more than 30% by weight, there is a problem with economic feasibility due to the use of excessive hydrochloric acid.

[0044] The wastewater separated in the above step 2) consists of caustic soda (NaOH), which is used to produce OH - (hydroxyl group) and OH the chloride ion of the hydroxyl by-product dissolved in dilute hydrochloric acid - It includes a step of substituting (hydroxyl group).

[0045] At this time OH - The method of providing (hydroxyl group) is to add caustic soda (NaOH) to provide OH - (Hydroxyl radical) can be generated to produce slaked lime and liquid slaked lime.

[0046]

[0047] The separation of the slaked lime (calcium hydroxide, Ca(OH)2)) and the solution in step 3) above can be accomplished using a filter press or centrifuge.

[0048]

[0049] When the slaked lime produced in the above step 4) is separated, wastewater is generated. This wastewater is a solution containing dissolved NaCl, and sodium hypochlorite (NaOCl) is produced through membrane electrolysis. This is recycled as a sterilizing disinfectant.

[0050] Additionally, chlorine gas is generated during the electrolysis of wastewater. When hydrogen gas is passed through the generated chlorine gas, hydrochloric acid is generated, and the generated hydrochloric acid is reused to dissolve aquatic by-products.

[0051]

[0052] If the produced calcium hydroxide is separated and dried, slaked lime is produced, and if not separated, it exists as liquid slaked lime dispersed in a solution.

[0053]

[0054] Hereinafter, the present invention will be described in more detail through manufacturing examples, examples, and experimental examples. However, the following manufacturing examples, examples, and experimental examples are merely examples for explaining the present invention, and the scope of the present invention is not limited by the following manufacturing examples, examples, and experimental examples.

[0055]

[0056] <Example 1>

[0057] Calcium carbonate (CaCO3) manufacturing

[0058] Calcium carbonate is produced by dissolving 1 mol of sodium carbonate (Na2CO3) in water, adding the dissolved solution to a solution in which 1 mol of calcium hydroxide (Ca(OH)2)) is dispersed, and stirring at room temperature for 1 hour. The yield at this time is close to 100%. When the produced calcium carbonate and solution are separated using quantitative filter paper (pore size 1-2 μm), the separated solution consists of caustic soda (NaOH).

[0059]

[0060] Dissolution of marine by-products (oyster shells)

[0061] 1 kg of oyster shells were dissolved in a solution of 2 L of hydrochloric acid diluted in 20 L of water and stirred at room temperature for 1 hour. This solution was purified by filtration using quantitative filter paper (pore size 5–8 μm), and only the clean solution was used.

[0062]

[0063] OH - (Hydroxyl) generation

[0064] Dissolve 1.6 kg of caustic soda in water in the filtered oyster shell solution, and add the dissolved solution to the purified solution of marine by-products (oyster shell) to remove OH -Stirring is carried out at room temperature for 30 minutes while providing (hydroxyl groups). This replaces the chloride ion of CaCl2 in the dissolved oyster shell, forming Ca(OH)2. This is used as a raw material to manufacture calcium carbonate. The yield is over 98%.

[0065]

[0066] <Example 2>

[0067] Dissolution of marine by-products (oyster shells)

[0068] 1 kg of oyster shells were dissolved in a solution of 2 L of hydrochloric acid diluted in 20 L of water and stirred at room temperature for 1 hour. This solution was purified by filtration using quantitative filter paper (pore size 5-8 μm) to use only the clean solution. If the carbon dioxide generated when the oyster shells are dissolved is recycled in the calcium carbonate manufacturing process of Example 1, the sodium carbonate raw material used can be reduced by 10-20% and the carbon dioxide can be recycled.

[0069]

[0070] OH - (Hydroxyl) generation

[0071] When the calcium carbonate formed in Example 1 is filtered using a centrifuge or quantitative filter paper (pore size 1-2 μm), wastewater is generated, and the wastewater contains NaOH, so when the wastewater is added to the filtered oyster shell solution, OH - (hydroxyl group). This is replaced by the chloride ion of CaCl2 in which the oyster shell is dissolved, forming Ca(OH)2.

[0072]

[0073] <Example 3>

[0074] electrolysis of wastewater

[0075] When the calcium hydroxide (Ca(OH)2) formed in Example 2 is centrifuged or filtered, wastewater is generated, and the wastewater contains NaCl. Sodium hypochlorite (NaOCl) is produced through self-made membrane electrolysis (titanium electrode, power consumption for producing 1 kg of effective chlorine: 3.5 kW / kgCL, 30 minutes of operation), so that the wastewater can be recycled.

[0076]

[0077] <Comparative Example>

[0078] Purchase commercial liquid slaked lime (20 wt% basis)

[0079] For comparison with the liquid slaked lime manufactured by the present invention, commercially available liquid slaked lime (Company A, 20 wt%) was purchased.

[0080]

[0081] Experimental Example 1

[0082] Test results of the calcium carbonate powder of the present invention

[0083] To determine the specifications of the calcium carbonate manufactured in Example 1, a test analysis was conducted according to the Food and Drug Administration's standards for food additives. The specifications are shown in Table 1 below.

[0084] <Calcium carbonate specifications of the present invention>

[0085] Item PMI Liquid slaked lime Appearance Odorless white fine powder Content (%) 99% Hydrochloric acid insoluble matter 0.1 mg Alkali metal and magnesium 3.8 mg Fluoride 2.26 ppm Barium not detected Heavy metals Arsenic: 0.0114 ppm Lead: 0.0028 ppm Cadmium: 0.0117 ppm Chromium: not detected Mercury: not detected

[0086] Test results of the slaked lime powder of the present invention

[0087] To determine the specifications of the slaked lime manufactured in Example 2, a test analysis was conducted according to the Food and Drug Administration's standards for food additives. The specifications are shown in Table 2 below.

[0088] <Specifications of the slaked lime of the present invention>

[0089] Item PMI Liquid slaked lime Appearance White Purity 98% Hydrochloric acid insoluble matter 6.6 mg Alkali metals and magnesium 11.9 mg Fluoride 2.9 ppm Barium not detected Heavy metals Arsenic: 1.32 ppm Lead: 0.06 ppm Cadmium: not detected Chromium: not detected Mercury: not detected

[0090] <Experimental Example 2> Analysis of the crystal structure of the slaked lime of the present invention

[0091] In order to analyze the crystal structure of calcium carbonate and slaked lime manufactured in the above examples, X-ray diffraction (XRD) analysis was performed, and the results are shown in Fig. 2. At this time, an X-ray diffractometer of the D / MAX2200V / PC model from Rigaku was used. As shown in Fig. 2, it can be seen that the precipitates manufactured in Examples 1 and 2 are calcium carbonate (CaCO3) and calcium hydroxide (Ca(OH)2), respectively, and no other impurities were detected.

[0092]

[0093] Experimental Example 3

[0094] Comparison of particle size distributions of calcium carbonate, liquid slaked lime of the present invention and commercial liquid slaked lime

[0095] The particle size distribution of the calcium carbonate and slaked lime manufactured in the above examples and the liquid slaked lime purchased in the comparative examples was measured using a particle size distribution device of the HORIBA LA-300 model, and the results are shown in Fig. 3. The calcium carbonate manufactured in Example 1 of the present invention has fine particles with an average particle size of less than 2 μm, and the slaked lime manufactured in Example 2 has fine particles with an average particle size of 2 μm and a narrow particle size distribution, and the commercial liquid slaked lime according to the comparative example has an average particle size of 21 μm and a very wide particle size distribution.

[0096] The above description is merely illustrative of the present invention. Those skilled in the art will appreciate that various modifications may be made without departing from the essential characteristics of the present invention. The scope of protection of the present invention should be construed in accordance with the claims below, and all techniques within the scope equivalent thereto should be construed as being included within the scope of the present invention.

Claims

1. 1) A step of forming calcium carbonate by reacting sodium carbonate (Na2CO3) and slaked lime (Ca(OH)2)) in a solution in water; 2) A step of separating calcium carbonate from the solution; 3) Dissolve the aquatic by-products in water containing diluted hydrochloric acid to obtain a calcium chloride (CaCl2) solution, and add the solution obtained in step 2) to it with OH - A step for completing slaked lime and liquid slaked lime by inputting it to provide (hydroxide) ; 4) A step of separating the slaked lime (Ca(OH)2) obtained in step 3) from the solution; 5) A step of making sodium hypochlorite (NaOCl) solution through electrolysis to recycle the wastewater generated in the above step 4); A continuous manufacturing method for calcium carbonate, slaked lime, liquid slaked lime, and sodium hypochlorite, characterized by including a step of recycling carbon dioxide generated when dissolving aquatic by-products in hydrochloric acid in the above step 3) by injecting it into the above step 1).

2. In paragraph 1, A continuous manufacturing method characterized in that the ratio of sodium carbonate (Na2CO3) and slaked lime (Ca(OH)2)) in the above step 1) is a molar ratio of 0.8 to 1.2 based on sodium carbonate.

3. In paragraph 1, A method characterized in that in the above step 3), the aquatic by-product additionally includes at least one selected from the group of calcium providing raw materials consisting of calcium carbonate, calcium oxide, calcium chloride, and calcium hydroxide. A continuous production method characterized in that, in paragraph 4.1, the by-product of the aquatic product is dissolved with water and hydrochloric acid to form calcium chloride.

5. A continuous manufacturing method characterized in that in paragraph 1, the aquatic by-product is the shell of one or more of oysters, clams, clams, cockles, abalone, and starfish.

6. A continuous manufacturing method characterized in that in the first paragraph, the water in which hydrochloric acid is diluted in step 3) is 10 to 30 wt%.

7. A continuous manufacturing method characterized in that, in the first paragraph, the slaked lime and liquid slaked lime completed in step 3) are manufactured without going through a heat treatment and calcination process. 8.1) A method of forming calcium carbonate by reacting sodium carbonate (Na2CO3) and slaked lime (Ca(OH)2)) in a solution in water; and 2) a step of separating calcium carbonate from the solution; wherein the solution separated in step 2) is used as a raw material for paper, fiber, detergent, soap, food, metal, electricity, wastewater treatment, or carbon dioxide absorbent.

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