Eco-friendly solid de-icing agent and its manufacturing method

Abstract

The present invention relates to an eco-friendly solid de-icing agent composition and a method of using the same, comprising a chloride-based de-icing component including sodium chloride (NaCl), calcium chloride (CaCl₂), and magnesium chloride (MgCl₂); an organic acid-based component and a phosphate-based buffering component capable of controlling and buffering pH changes occurring during the de-icing process; and one or more color indicators that change color according to pH changes. It is designed to form a structure in which pH changes over time are controlled stepwise throughout the entire process of melting and ice melting upon contact with snow or ice on the road surface, thereby reducing steel corrosion, concrete deterioration, and the burden on the soil and water environment, while simultaneously satisfying visibility and reliability that allow users and managers to intuitively recognize the progress of snow removal.

Description

Technology Field

[0001] The present invention relates to a solid de-icing agent that is sprayed onto various surfaces where snow and ice form, such as roads, bridges, expressways, parking lots, and pedestrian walkways, to perform an ice-melting action.

[0002] More specifically, the invention relates to an eco-friendly solid de-icing agent composition and a method for manufacturing the same, which is based on a chloride-based de-icing component but also includes an organic acid-based component and a phosphate-based buffering composition component capable of controlling and buffering pH changes occurring during the de-icing process, and a color indicator function that changes color in stages according to the progress of de-icing and ice melting, thereby reducing steel corrosion, concrete deterioration, and the burden on soil and water systems, while allowing users and managers to intuitively recognize the progress of de-icing. Background Technology

[0004] Since icing on roads and sidewalks during the winter acts as a major cause of traffic accidents and pedestrian safety incidents, various de-icing agents with sodium chloride (NaCl) and calcium chloride (CaCl2) as main components are used to prevent this.

[0005] However, conventional chloride-based de-icing agents have the following problems.

[0006] First, chloride ions (Cl - There is a problem that continuous exposure to ) accelerates the corrosion of steel materials, such as bridges, guardrails, and reinforcing bars in reinforced concrete structures. In particular, it is known that the corrosion rate accelerates when the pH locally shifts to acidic or alkaline during the melting process.

[0007] Second, the repeated application of de-icing agents causes scaling, microcracks, and surface spalling on concrete surfaces, which shortens the lifespan of structures. This is the result of the combined effects of not only the chlorides themselves but also the rapid pH changes and moisture penetration that occur during the de-icing process.

[0008] Third, because it is difficult to visually determine the progress of snow removal and ice melting, existing de-icing agents are frequently sprayed excessively beyond what is necessary, which leads to increased environmental burden and maintenance costs.

[0009] Recently, research on eco-friendly de-icing agents has been conducted to address these issues; however, most technologies are limited to merely slightly reducing the amount of chlorides used or applying small amounts of alternative components. Furthermore, no technology has yet been presented that simultaneously satisfies pH changes over time during the de-icing process, visual feedback of the de-icing environment based on pH changes, and compositional designs that structurally meet environmental label certification standards. Prior art literature

[0011] Republic of Korea Registered Patent Publication No. 10-1663165 Republic of Korea Registered Patent Publication No. 10-2132563 Republic of Korea Registered Patent Publication No. 10-2703699 The problem to be solved

[0012] The objective of the present invention is to solve the problems of the conventional technology described above, and to simultaneously improve environmental friendliness, safety, and ease of use by structurally controlling the pH change occurring during the snow removal and melting process while maintaining the excellent ice-melting performance of chloride-based de-icing agents, and visualizing the pattern of such change as a color change.

[0013] To explain in detail, it is as follows.

[0014] First, the purpose is to provide an eco-friendly solid de-icing agent that can reduce steel corrosion and concrete deterioration by buffering the pH of the de-icing environment from the initial stage where the de-icing agent comes into contact with snow or ice and dissolves and diffuses, to the stage after a significant amount of melting has occurred, so that the pH does not shift to an excessively acidic or alkaline range.

[0015] Second, by appropriately combining phosphate-based buffering compositions, organic acid-based components, glycerol, etc., the invention provides a de-icing agent that mitigates the corrosion-promoting effect of chloride ions generated during the de-icing process and satisfies the environmental safety requirements of the environmental label certification standards through compositional design.

[0016] Third, the purpose is to enable users and managers to intuitively recognize the progress of snow removal and ice melting visually by causing one or more selected or mixed color indicators, such as anthocyanin, BTB series, curcumin, and cresol red, to change color in stages in conjunction with pH changes occurring over time after the de-icing agent is sprayed.

[0017] Fourth, the above color change is not merely a visual effect, but is intended to provide snow removal workers with a criterion for judging the timing of re-spraying, and to function as a reliability indicator for general users and consumers to confirm that the de-icing agent is actually working.

[0018] Fifth, by achieving the above objectives, the aim is to provide an eco-friendly solid de-icing agent composition and a method of use thereof that can be stably applied in various actual road environments, such as roads, bridges, and pedestrian walkways, while preventing overspray and reducing maintenance costs. means of solving the problem

[0020] To solve the above problem, the present invention provides an eco-friendly solid de-icing agent composition comprising: a chloride-based de-icing component including sodium chloride (NaCl), calcium chloride (CaCl₂), and magnesium chloride (MgCl₂); one or more organic acid-based components selected from the group consisting of hydrated citric acid, anhydrous citric acid, sodium citrate, and trisodium citrate; a pH buffering component including one or more phosphate-based components selected from the group consisting of sodium acidic phosphate, sodium acidic pyrophosphate, sodium polyphosphate, potassium phosphate, and calcium phosphate; a color indicator that changes color according to pH change and glycerol; wherein the eco-friendly solid de-icing agent forms a double pH buffering structure that maintains the pH of an aqueous solution in the range of 4.5 to 7.5 through a shift in buffer equilibrium as the de-icing reaction proceeds.

[0021] In the present invention, the eco-friendly solid de-icing agent is characterized by comprising, based on the total weight, 55-70% by weight of sodium chloride, 20-28% by weight of calcium chloride, 3-10% by weight of magnesium chloride, 0.3-3% by weight of an organic acid component, 0.2-2% by weight of a phosphate buffering component, 0.01-1% by weight of glycerol, 0.005-0.7% by weight of a color indicator, and the remainder being other functional additives.

[0023] In addition, the present invention is characterized by the fact that the color indicator changes color stepwise or continuously in conjunction with the pH change over time after the de-icing agent is sprayed, thereby visually indicating the progress of de-icing and ice melting, and the color indicator comprises one or more of anthocyanin, BTB salt, sodium alizarin sulfonate, bromocresol green, chlorophenol red, bromocresol purple, bromochlorophenol blue, bromophenol red, curcumin, cresol red, p-nitrophenol, neutral red, and 1-naphtholphthalein, and is applicable even in low-temperature environments with an ambient temperature of 0℃ or lower.

[0024] In addition, the present invention is configured such that steel corrosion and concrete damage are reduced by the combination of the magnesium chloride, organic acid-based components, and phosphate-based buffering components, and is characterized by satisfying the environmental label certification test standards, which include steel corrosion tests, concrete damage tests, and environmental hazard tests.

[0025] In addition, the present invention is characterized in that the organic acid-based component and the phosphate-based buffer component are each added independently to form a buffer structure of two or more components.

[0026] In addition, the present invention is characterized in that the color indicator is combined in multiple ways to cover different pH ranges, and the color change enables visual recognition of the melting progress status, indicating that the de-icing agent is functioning normally.

[0028] In the present invention, a method for manufacturing the eco-friendly solid de-icing agent comprises the steps of: preparing the eco-friendly solid de-icing agent raw material (S100); introducing sodium chloride (NaCl) into a first stirrer (S200); introducing calcium chloride (CaCl₂) and magnesium chloride (MgCl₂) into the first stirrer and mixing them further (S300); forming a pH buffering function comprising one or more organic acid components selected from the group consisting of hydrated citric acid, anhydrous citric acid, sodium citrate, and trisodium citrate; and one or more phosphate components selected from the group consisting of acidic sodium phosphate, acidic sodium pyrophosphate, sodium polyphosphate, potassium phosphate, and calcium phosphate (S400); forming a stabilization structure such that the pH is maintained in the range of 4.5 to 7.5 as the de-icing reaction proceeds (S500); introducing a color indicator, glycerol, and one or more functional additives into a second stirrer and mixing them (S600); The method is characterized by including the step of mixing the raw materials mixed in the second stirrer by introducing them into the first stirrer (S700); the step of uniformly mixing, drying, and granulating after steps S100 to S700 (S800); and the step of completing the eco-friendly solid de-icing agent (S900).

[0029] In addition, in the present invention, the eco-friendly solid de-icing agent is characterized by being formed with a particle size of 0.5 to 10 mm through drying and granulation processes after the step of mixing sodium chloride (NaCl) 55 to 70 wt%, calcium chloride (CaCl₂) 20 to 28 wt%, magnesium chloride (MgCl₂) 3 to 10 wt%, organic acid component 0.3 to 3 wt%, phosphate buffer component 0.2 to 2 wt%, glycerol 0.01 to 1 wt%, color indicator 0.005 to 0.7 wt%, and other functional additives based on the total weight.

[0030] In addition, the present invention is characterized by the inclusion of glycerol and magnesium chloride so that the buffering function is maintained even in a low-temperature environment where the ambient temperature is -15℃ or lower. Effects of the invention

[0032] The eco-friendly solid de-icing agent composition and the method of use according to the present invention are designed to form a dual pH structure in which the pH change over time is controlled stepwise throughout the entire process of melting and ice melting upon contact with snow or ice on the road surface by mixing chloride-based de-icing components including sodium chloride (NaCl), calcium chloride (CaCl₂), and magnesium chloride (MgCl₂), organic acid-based components, phosphate-based buffering components, and one or more color indicators that change color according to pH change in an optimal ratio, thereby providing the effect of simultaneously satisfying de-icing performance, compliance with environmental label certification, protection of steel and concrete, and visibility and reliability from the perspective of users and consumers. Brief explanation of the drawing

[0034] FIG. 1 is a flowchart for manufacturing an eco-friendly solid de-icing agent according to a preferred embodiment of the present invention. FIG. 2 is a photograph of an eco-friendly solid de-icing agent according to a preferred embodiment of the present invention. Specific details for implementing the invention

[0035] To achieve the above objective, the eco-friendly solid de-icing agent according to the present invention comprises the following composition.

[0036] The de-icing agent of the present invention basically comprises chloride-based de-icing components including sodium chloride (NaCl), calcium chloride (CaCl2), and magnesium chloride (MgCl2), and these chloride-based components lower the melting point of snow and ice to induce rapid melting, and in particular, the magnesium chloride included in the present invention plays a role in increasing the duration of melting even at low temperatures.

[0037] In addition, the de-icing agent of the present invention comprises an organic acid-based component and a phosphate-based buffering component to control pH changes occurring during the de-icing and melting process. The components may consist of one or more of the organic acid-based components, including hydrated citric acid, anhydrous citric acid, sodium citrate, and trisodium citrate, and the phosphate-based components, such as sodium acid phosphate, sodium acid pyrophosphate, sodium polyphosphate, potassium phosphate, and calcium phosphate, and may be used as a single component or in the form of a combination of two or more components.

[0038] The above organic acid-based components and phosphate-based buffering components suppress rapid pH fluctuations that may occur during the initial stages of de-icing agent application, thereby mitigating alkaline or acidic environments, and play a role in stabilizing the pH of the aqueous solution formed as ice melting progresses from a weakly acidic to a neutral range.

[0039] In addition, the de-icing agent of the present invention may include glycerol (C3H5(OH)3). Glycerol has a high affinity for moisture, so it gently controls the diffusion of de-icing components and, at the same time, alleviates rapid moisture movement on the concrete surface, thereby providing the effect of reducing surface deterioration and the occurrence of microcracks.

[0040] The de-icing agent of the present invention also includes one or more color indicators to implement a color indicator function, and the color indicators are selected such that their color changes according to pH changes during the de-icing process, and may include, for example, one or more of anthocyanin, BTB salt, sodium alizarin sulfonate, bromocresol green, chlorophenol red, bromocresol purple, bromochlorophenol blue, bromophenol red, curcumin, cresol red, p-nitrophenol, neutral red, and 1-naphtholphthalein.

[0041] These color indicators change color continuously or in stages in response to changes in pH over time from immediately after the de-icing agent is sprayed until a significant amount of ice melting has occurred, thereby visually expressing the progress of the de-icing action.

[0042] In the following, preferred embodiments and examples are described to aid in understanding the present invention.

[0043] However, the following examples are intended to illustrate the technical concept of the present invention and are not limited to the scope of the present invention.

[0044] The eco-friendly solid de-icing agent of the present invention basically comprises a chloride-based de-icing component, a pH buffering component, a color indicator component, and optionally glycerol, and various modifications can be made depending on the combination and content of each component.

[0045] This Example 1 relates to the composition of an eco-friendly solid de-icing agent for use in an ambient temperature range of about -5°C to -10°C.

[0046] The de-icing agent of Example 1 was prepared with the following compositional ratio relative to the total weight.

[0047] It contains 55-70% by weight of sodium chloride (NaCl), 20-28% by weight of calcium chloride (CaCl₂), 3-10% by weight of magnesium chloride (MgCl₂), 0.3-3% by weight of organic acid components, 0.2-4% by weight of phosphate buffer components, 0.01-1% by weight of glycerol, 0.005-0.7% by weight of color indicator, and the remainder being other functional additives, preferably 0.3-6.485% by weight.

[0048] The above color indicator is based on anthocyanin, but is formulated to exhibit a color change in the range of weakly acidic to neutral (pH approximately 4.5 to 7.8) by using various color indicators such as BTB salt in combination.

[0049] As a result of spraying the de-icing agent of the present embodiment onto a road surface where snow and ice had formed, the melting reaction began immediately after spraying, and it was confirmed that most of the ice was removed after about 60 minutes.

[0050] In the ambient temperature range of Example 1 above, after the de-icing agent is sprayed onto the road surface, initial molten water is formed by the rapid dissolution of calcium chloride and magnesium chloride powders, and the pH starts in a weakly acidic range of about 4.5 to 5.8, passes through a weakly neutral range of pH 6.0 to 6.6 over time, and gradually changes to a neutral range of pH 6.8 to 7.5 at the stage where the de-icing reaction stabilizes.

[0051] Accordingly, the anthocyanin-based color indicator displayed an initial red to magenta color in the acidic range, followed by a gradual color change to pink to light purple in the weakly neutral range, and then to dark purple to bluish-purple in the neutral range. This color change serves to visually indicate the progress of the de-icing reaction in chronological order.

[0052] Example 2 of this case involves spraying the de-icing agent of Example 1 under normal actual road surface conditions and observing changes in pH and color based on anthocyanin over time.

[0053] The results of inferring and observing environmental changes over time following the application of de-icing agents are as follows.

[0054] Immediately after spraying: pH approximately 4.9–5.1, maintaining a magenta hue.

[0055] After 15 minutes: pH approximately 5.2–5.6, maintaining a purplish-red hue, however, the BTB salt maintains a yellowish hue.

[0056] After 30 minutes: pH approximately 5.7–6.2, color gradually shifts to a deep pink hue.

[0057] After 45 minutes: pH approximately 6.3–6.7, deep pink hues dominant, however, the BTB salt maintains a yellowish-green hue.

[0058] After 60 minutes: pH approximately 6.8–7.2, deep pink gradually changes to purple hues, and the complete melting state is identifiable; however, BTB salts change to a greenish hue.

[0059] Through this, it was confirmed that as snow removal and ice melting proceed, the pH does not fluctuate rapidly but remains stable in the weakly acidic to weakly neutral range, and the color changes gradually.

[0060] In a low-temperature environment with an ambient temperature of 0°C or lower, pH changes began gradually immediately after the application of the de-icing agent. Initially, the pH was maintained in the range of approximately 4.8 to 5.3, and then gradually rose to the range of 5.6 to 6.6 due to the exothermic dissolution reaction of calcium chloride. After a certain period of time, it reached the neutral range of pH 6.8 to 7.2. Accordingly, the anthocyanin-based color indicator maintained a deep pink color from an initial magenta for a relatively long time, and then gradually changed to a purple hue.

[0061] This gradual color change made it possible to clearly perceive that the snow removal reaction is continuing even in low-temperature environments.

[0062] This Example 3 is intended to verify the applicability in a low-temperature environment where the ambient temperature is 0°C or lower.

[0063] A de-icing agent prepared by relatively increasing the magnesium chloride content (7–10 wt%) in the composition of Example 1 above was applied under conditions of -5°C, -10°C, -15°C, and -20°C, respectively. As a result,

[0064] In environments of -5℃ and -10℃, time-dependent ice melting and color changes similar to those in Example 1 were observed, and

[0065] Even in an environment of -15℃, the ice melting speed decreased slightly, but a significant snow removal effect was confirmed within 60 to 90 minutes.

[0066] In a -20℃ environment, the initial melting rate was slow, but gradual melting continued due to the action of magnesium chloride.

[0067] Even during this process, the pH was maintained in the range of approximately 4.8 to 7.0, and the color indicator function operated normally.

[0068] In addition, the anthocyanin-based color indicator exhibited a gradual color change from an initial magenta to deep pink or purple hues. This color change visually indicated that the snow removal effect lasted for a long time.

[0069] Example 4 is a case where a plurality of color indicators are applied to expand the color indication range.

[0070] In addition to the composition of Example 1 above, one or more of methyl red, curcumin, and cresol red were additionally included as color indicators along with anthocyanin.

[0071] As a result, a continuous color change occurred in the pH range of approximately 4.7 to 7.6, confirming the effect of improved color visibility even in actual road environments with high moisture content or road surface contamination.

[0072] Due to the elution characteristics of flake-type chloride in a low-temperature environment, the change in pH proceeded more gradually; the initial pH was maintained in the range of approximately 5.0 to 5.8 for a long time, then gradually increased to the range of 6.0 to 6.5, and finally reached the neutral range of pH 6.7 to 7.6. Accordingly, the color indicator maintained a magenta color initially and a pink color during the middle stage for a relatively long time, and then gradually changed to a purple hue.

[0073] These characteristics made it possible to visually confirm the persistence and stability of the snow removal reaction even under low-temperature conditions.

[0074] The results of Examples 1 to 4 above are shown in Table 1 below as follows.

[0075]

[0076] In addition, a comparative analysis of the functional characteristics of conventional chloride-based de-icing agents and the eco-friendly solid de-icing agent of the present invention confirms that they are as shown in Table 2 below.

[0077]

[0078] Therefore, an important feature of the eco-friendly solid de-icing agent according to the present invention is that it is designed to form a structure in which the pH change over time is controlled stepwise throughout the entire process in which the de-icing agent comes into contact with snow or ice on the road surface, dissolves, and melting proceeds.

[0079] Specifically, in the initial stage immediately after the de-icing agent is sprayed, the melting reaction is initiated by the dissolution of chloride-based de-icing components, and at this time, the pH may fluctuate locally. However, in the present invention, by working together with phosphate-based buffering components and organic acid-based components including hydrated citric acid, the pH is prevented from shifting excessively into an acidic (pH less than 4.0) or alkaline (pH greater than 8.0) range and stabilized to a weakly acidic to neutral range.

[0080] The present invention is not a simple acidic composition, but a stepwise pH control system utilizing an increase in ion concentration and a shift in phosphate buffer equilibrium induced by the dissolution of calcium chloride.

[0081] pH shifts naturally occur as the melting reaction proceeds without the addition of external additives, and suppress rapid increases or decreases in pH.

[0082] This pH buffering effect persists even after a significant amount of ice melting has occurred, thereby maintaining a relatively stable chemical environment throughout the snow removal environment.

[0083] As a result, the steel corrosion reaction promoted by chloride ions is suppressed, and scaling, spalling, and the occurrence of microcracks on the surface of concrete structures are significantly reduced.

[0084] In particular, the magnesium chloride (MgCl₂) included in the present invention, when used in combination with sodium chloride and calcium chloride, improves the snow removal efficiency per unit chloride ion while simultaneously maintaining a stable snow removal reaction through its relatively slow dissolution rate and low eutectic point characteristics.

[0085] As a result, it forms a structure that is advantageous for meeting the requirements for reducing steel corrosion and concrete damage in environmental label certification, while maintaining snow removal performance.

[0086] In addition, the glycerol included in the present invention inhibits the rapid movement of de-icing components along with moisture, thereby mitigating rapid moisture absorption and desorption on road surfaces and concrete surfaces.

[0087] Accordingly, the deterioration of the concrete surface is reduced even in repeated freezing and thawing environments, and the durability of the de-icing agent in actual usage environments is improved.

[0088] Meanwhile, another important effect of the present invention is the color indication function.

[0089] In the present invention, by including one or more color indicators that change color according to changes in pH of the snow removal environment, the progress of ice melting over time after the snow removal agent is sprayed can be visually confirmed.

[0090] For example, in the initial stage of de-icing agent application, a specific color appears due to anthocyanins extracted from natural raw materials or other chemically stable color indicators (changing in the pH range of 3.0 to 8.6), and as melting progresses, the color gradually changes in conjunction with the change in pH.

[0091] These color changes are not merely a visual effect; they provide snow removal workers with a criterion to determine whether reapplication is necessary, and function as a reliability indicator that allows general users and consumers to intuitively recognize that the de-icing agent is working properly.

[0092] In particular, when using multiple combinations of color indicators, a wider pH range of the snow removal environment can be covered, and stable color changes can be achieved even in situations with varying moisture content, contaminants, and temperature conditions, such as actual road environments.

[0093] Thus, the eco-friendly solid de-icing agent according to the present invention provides significantly enhanced composite functions that simultaneously satisfy de-icing performance, compliance with environmental label certification, protection effects for steel and concrete, and visibility and reliability from the perspective of users and consumers. Explanation of the symbols

[0095] S100 ; Step of preparing raw materials for eco-friendly solid de-icing agents S200 ; Step of introducing sodium chloride (NaCl) into the first stirrer S300 ; Calcium chloride (CaCl₂) and magnesium chloride (MgCl₂) in the first stirrer Input and mixing steps S400; organic acid components and buffer components are introduced into a second stirrer and mixed. Steps to form a pH buffer function S500; stabilization that causes pH to change stepwise as the reaction proceeds Steps to form the structure S600 ; Color indicator, glycerol and one or more functional additives Step of feeding into the second stirrer and additionally mixing S700 ; The raw materials mixed in the second stirrer are fed into the first stirrer, additional The mixing step or the mixtures in the first stirrer and the second stirrer, respectively Step of introducing raw materials into the third stirrer and further mixing S800 ; Step for drying and granulation S900 ; Step to completing the eco-friendly solid de-icing agent

Claims

Claim 1 An eco-friendly solid de-icing agent composition comprising: a chloride-based de-icing component including sodium chloride (NaCl), calcium chloride (CaCl₂), and magnesium chloride (MgCl₂); one or more organic acid-based components selected from the group consisting of hydrated citric acid, anhydrous citric acid, sodium citrate, and trisodium citrate; a pH buffering component including one or more phosphate-based components selected from the group consisting of sodium acidic phosphate, sodium acidic pyrophosphate, sodium polyphosphate, potassium phosphate, and calcium phosphate; a color indicator that changes color according to pH change; and glycerol; wherein the eco-friendly solid de-icing agent is characterized by forming a double pH buffering structure that maintains the pH of an aqueous solution in the range of 4.5 to 7.5 through a shift in buffer equilibrium as the de-icing reaction proceeds. Claim 2 An eco-friendly solid de-icing agent composition according to claim 1, wherein the eco-friendly solid de-icing agent comprises, based on the total weight, 55-70% by weight of sodium chloride (NaCl), 20-28% by weight of calcium chloride (CaCl₂), 3-10% by weight of magnesium chloride (MgCl₂), 0.3-3% by weight of an organic acid component, 0.2-2% by weight of a phosphate component, 0.01-1% by weight of glycerol, 0.005-0.7% by weight of a color indicator, and the remainder being other functional additives. Claim 3 delete Claim 4 An eco-friendly solid de-icing agent composition according to claim 1, characterized in that the color indicator changes color stepwise or continuously in conjunction with pH changes over time after the de-icing agent is sprayed, thereby visually indicating the progress of de-icing and ice melting. Claim 5 An eco-friendly solid de-icing agent composition according to claim 4, wherein the color indicator comprises one or more of anthocyanin, BTB salt, sodium alizarin sulfonate, bromocresol green, chlorophenol red, bromocresol purple, bromochlorophenol blue, bromophenol red, curcumin, cresol red, p-nitrophenol, neutral red, and 1-naphtholphthalein, and is applicable even in low-temperature environments with an ambient temperature of 0°C or lower. Claim 6 An eco-friendly solid de-icing agent composition according to claim 1, characterized in that it is configured to reduce steel corrosion and concrete damage through a combination of magnesium chloride, organic acid-based components, and phosphate-based components, and satisfies the environmental label certification test standards including steel corrosion tests, concrete damage tests, and environmental hazard tests. Claim 7 An eco-friendly solid de-icing agent composition according to claim 1 or claim 2, characterized in that the organic acid-based component and the phosphate-based component are each independently added to form a buffer structure of two or more components. Claim 8 delete Claim 9 An eco-friendly solid de-icing agent composition according to claim 5, characterized in that the color indicators are combined in multiples to cover different pH ranges. Claim 10 An eco-friendly solid de-icing agent composition according to claim 1, characterized in that the color change allows the melting progress status to be visually recognized as the de-icing agent is operating normally. Claim 11 A method for manufacturing an eco-friendly solid de-icing agent, comprising the step of preparing the eco-friendly solid de-icing agent raw material (S100); A step of introducing sodium chloride (NaCl) into a first stirrer (S200); a step of introducing and mixing calcium chloride (CaCl₂) and magnesium chloride (MgCl₂) into the first stirrer (S300); a step of forming a pH buffering function comprising one or more organic acid components selected from the group consisting of hydrated citric acid, anhydrous citric acid, sodium citrate, and trisodium citrate; and one or more phosphate components selected from the group consisting of acidic sodium phosphate, acidic sodium pyrophosphate, sodium polyphosphate, potassium phosphate, and calcium phosphate (S400); a step of forming a stabilization structure to maintain the pH in the range of 4.5 to 7.5 as the de-icing reaction proceeds (S500); a step of introducing and mixing a color indicator, glycerol, and one or more functional additives into a second stirrer (S600); a step of introducing the raw materials mixed in the second stirrer into the first stirrer and mixing them (S700); the A method for manufacturing an eco-friendly solid de-icing agent, characterized by including steps S100 to S700, a step of uniformly drying and granulating (S800); and a step of completing the eco-friendly solid de-icing agent (S900). Claim 12 A method for manufacturing an eco-friendly solid de-icing agent according to claim 11, characterized in that the eco-friendly solid de-icing agent is formed to a particle size of 0.5 to 10 mm through drying and granulation processes after the step of mixing sodium chloride (NaCl) 55 to 70 wt%, calcium chloride (CaCl₂) 20 to 28 wt%, magnesium chloride (MgCl₂) 3 to 10 wt%, organic acid component 0.3 to 3 wt%, phosphate component 0.2 to 2 wt%, glycerol 0.01 to 1 wt%, color indicator 0.005 to 0.7 wt%, and the remainder other functional additives based on the total weight. Claim 13 A method for manufacturing an eco-friendly solid de-icing agent according to claim 11, wherein the color indicator comprises one or more of anthocyanin, BTB salt, sodium alizarin sulfonate, bromocresol green, chlorophenol red, bromocresol purple, bromochlorophenol blue, bromophenol red, curcumin, cresol red, p-nitrophenol, neutral red, and 1-naphtholphthalein. Claim 14 A method for manufacturing an eco-friendly solid de-icing agent according to claim 11, characterized in that the eco-friendly solid de-icing agent comprises glycerol and magnesium chloride so that a buffering function is maintained even in an environment where the ambient temperature is -15℃ or lower.

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