WO2008111704A1

WO2008111704A1 - Liquid composition of non-chlorinated compound for removing snow or ice and method for removing snow or ice

Info

Publication number: WO2008111704A1
Application number: PCT/KR2007/002788
Authority: WO
Inventors: Hyoung Guen Lee; Man Soo Jeon; Nam Kyu Park; Chul Ho Ahn
Original assignee: Hyoung Guen Lee
Priority date: 2007-03-14
Filing date: 2007-06-08
Publication date: 2008-09-18
Also published as: KR101168946B1; KR20080084039A

Abstract

Disclosed herein are a non-chlorinated liquid composition for snow/ice removing and preventing freezing in winter and a method of removing snow by the use of the composition. The composition of the present invention comprises alkali metal and alkaline earth metal acetate and formate, chitosan, corrosion inhibitor, and water. The composition of the present invention is not corrosive, is environment-friendly, has no remaining odor, and does not undergo recrystallization thereby to show a good effect on snow removal. The present invention provides a method of removing snow by heating the composition of the present invention and spraying the heated composition on road and the like to melt accumulated snow. The method of the present invention shows a good effect on snow removal, since the heating synergist ical Iy acts with the snow-removal property of the composition per se.

Description

[DESCRIPTION]

[Invention Title]

LIQUID COMPOSITION OF NON - CHLORINATED COMPOUND FOR REMOVING SNOW OR ICE AND METHOD FOR REMOVING SNOW OR ICE

[Technical Field]

The present invention relates to a non-chlorinated liquid composition for snow or ice removing or anti-freezing, and a method of removing snow or ice using the composition. More specifically, the present invention relates to a non-chlorinated liquid composition for snow or ice removing or anti- freezing, wherein the odor of acetate and formate is removed and recrystallization is prevented, and a method of removing snow or ice, which comprises heating the non-chlorinated liquid composition and spraying it, thereby exhibiting a synergistic effect on snow or ice removing and effectively removing snow or ice.

[Background Art]

Calcium chloride and sodium chloride are currently used as an agent for removing snow and ice over the inside and outside of the country. North America countries such as U.S.A., Canada, etc. commonly uses a mixture of halite (NaCl) or calcium chloride and sand. Japan generally uses a method of removing snow by spraying calcium chloride. The method is also conventionally used in Korea.

However, the typical method of spraying calcium chloride brings an enormous amount of traffic accidents and environmental and economical loss as follows: metals in automobile, concrete for roads and bridges, and iron frames of structures and fixtures are made corrosive, which needs considerable expense to recover them; soils and rivers are contaminated; environmental and ecological damages such as death of roadside trees and plant, etc. rise; after spraying an agent for removing snow such as calcium chloride, sand, etc., eliminating the agent goes to expense.

To resolve said problems by chlorinated agents for snow removing, a variety of non-chlorinated agents for snow removing have been developed. For example, urea and calcium magnesium acetate (CMA) have been known in the art. Korean Patent Registration No. 0588820 discloses a non-chlorinated and low corrosive liquid composition for snow removing, but the composition comprises a large amount of non-biodegradable organic materials of ethanol, PVA, ethylene glycol and the like which are environmental loads and expensive, thereby taking a problem on a commercial scale.

Korean Patent Registration No. 0179334 describes a non-chlorinated agent for snow removing which is prepared by mixing acetic acid and sodium silicate with a powder of shell and/or dolomite. However, the method has a limited capability and requires complex processes and thus has a problem with profitability. Therefore, the method could not become commercial.

Meanwhile, CMA (calcium acetate/magnesium acetate), which has been well known as a non-chlorinated agent for snow removing, is non-toxic; can be degradable into carbon dioxide; when dissolved in water concurrently with calcium chloride, generates a heat; and shows a similar melting efficacy to that of salts or calcium chloride {S.A. Dunn.R.U.Schenk, Federal Highway Administration Report FHWA/RD-79/108, Washington, DX. 1980}.

U.S. Patent No. 6,821,453 and Korean Patent Registration No. 0636294 disclose a chlorinated composition for snow removing in order to reduce corrosion. Incorporating additives to reduce corrosion into the composition may reduce a degree of corrosion, but the composition cannot ultimately solve the problems of corrosion and environment.

The researches to develop environment-friendly agent for snow removing has been focused on overcoming the side effects of environmental and ecological destructions and attenuating corrosion by the agent and the purposes have been partially attained. However, since the unit cost of materials which are comprised in the composition is high, the composition could be utilized in a limited area such as airport. Therefore, there is a need to develop a new composition for snow removing and a method for removing snow which is low corrosive, environment-friendly and economical to the extent that the composition can be put to practical use.

[Disclosure]

[Technical Problem]

Accordingly, the present inventors have made efforts to develop an alternative agent for snow removing which overcomes the problems of a chlorinated solid agent for snow removing which uses calcium chloride, sodium chloride, etc., reduces metal corrosion and destruction of environment, and is so economical as to be commercial, and, finally, have found that a liquid agent for removing snow can be prepared by mixing an aqueous solution of acetate or formate such as potassium acetate, potassium formate, sodium acetate, sodium formate, calcium acetate, calcium formate with chitosan, and that the condition or situation for using the agent, as shown below, can be considerably improved with a high performance and a reduction of cost accompanied by spraying the agent: when the agent is sprayed after being heated, the amount of snow/ice to be removed can be highly increased, the speed of removing snow/ice is fast, the agent is non-corrosive and does not contaminate environment and ecological system, spraying the agent is easy, there is no recrystallization after being sprayed, the capability of snow/ice removing is excellent, the liquid agent can be applied to an automotive spraying device, the absolute amount of the agent to be used for removing snow/ice can be dramatically reduced.

An object of the present invention is to provide a non-chlorinated liquid composition which effectively removes snow/ice without contaminating environment and ecosystem.

Another object of the present invention is to provide a method of removing snow/ice, which comprises heating the non-chlorinated liquid composition and spraying the heated composition, thereby eliminating snow or ice which lies on road and the like. In the present method, the composition is not toxic and the heating synergistically acts on snow/ice removal together with the snow removal composition per se, so that snow and ice can be effectively removed.

[Technical Solution]

To achieve said objects, the present invention provides a non- chlorinated liquid composition for snow removing, which comprises 10 to 60% by weight of at least one organic acid salt selected from the group consisting of alkali metal and alkaline earth metal acetate and alkali metal and alkaline earth metal acetate formate, 0.01 to 5% by weight of at least one polysaccharide selected from the group consisting of chitin, chitosan and chitin-chitosan wherein acetyl group is partially removed from chitin, and a residual amount of water. Adding chitosan to the composition prevents formates or acetates from being recrystallized, thereby improving storage stability and providing a high snow removing ability. The composition can further comprise 0.001 to 3% by weight of corrosion inhibitor.

In the composition of the present invention, the organic acid salt is preferably selected from potassium acetate, potassium formate, sodium acetate, sodium formate, calcium acetate, calcium formate, magnesium acetate, and magnesium formate, and the corrosion inhibitor is preferably selected from azole, phosphor carboxylic acid, straight chain carboxylic acid, and phosphoric acid. The freezing point of the composition is preferably -20° C to -70° C.

Further, the present invention provides a method of removing snow. The method comprises heating a non-chlorinated liquid composition to a temperature of 40° C to 120° C, wherein the composition comprises 10 to 60% by weight of at least one organic acid salt selected from the group consisting of acetates of alkali metal and alkaline earth metal and formates of alkali metal and alkaline earth metal and a residual amount of water, and spraying the heated composition.

Preferably, the non-chlorinated liquid composition used in the method of the present invention further comprises 0.01 to 5% by weight of at least one polysaccharide selected from the group consisting of chitin, chitosan and chitin-chitosan wherein acetyl group is partially removed from chitin. Preferably, the composition further comprises 0.001 to 3% by weight of corrosion inhibitor.

The preferred corrosion inhibitor and organic acid salt which are comprised in the non-chlorinated liquid composition for the method of the present invention are those as listed above and the freezing point of the composition used in the method is also the same as that shown above.

[Advantageous Effects]

The non-chlorinated liquid composition prevents formates or acetates from being recrystallized due to the addition of chitosan to the composition, thereby improving storage stability and providing a high snow removing abi lity.

Further, the method of the present invention which sprays the non- chlorinated liquid composition after heating the composition provides the following advantages or effects:

Firstly, the method improve the speed of snow removing due to spraying the heated composition,

Secondly, the method increases the amount of snow removing due to spraying the heated composition,

Thirdly, snow lying in a thick of 3 to 5cm, pressured snow, snow frozen on a road can be removed with a spraying car equipped with a heating means at a time,

Fourthly, after molten, the snow is not re-frozen, thereby making the surrounding snow/ice molten consistently,

Fifthly, the composition can be heated directly or by adding boiled water thereto, applied to the zone to which the use of calcium chloride is prohibited such as amusement park for children, rides, staircases, construction sites, temples, etc., and can be easily adapted to the regions which need an agent for snow removing in the form of liquid,

Sixthly, the method does not make iron frames of structure, concrete structure, automobile, etc. corrosive and can avoid the contamination of environment and the destruction of ecosystem such as river and soil contamination, death of roadside trees and plant, etc., thereby saving expense incurred by such damage and cost for recovery, and since the freezing point of the composition is very low, even though the composition is diluted after snow/ice removing, the possibility that the diluted composition is refrozen is low and, thus, traffic accident and loss of life caused by refreezing can be avoided, Seventhly, since the composition is heated and snow is consistently removed, the effect is synergistic and thus a small amount of the composition can provide sufficient effect on snow removing.

Eighthly, since the composition is liquid, its prezervation is easy,

Ninthly, since the composition is non-corrosive and liquid, when the composition is applied to automatic spraying device, expense for installation and maintenance can be reduced,

Tenthly, the effect for snow removing can be maintained for a long time, compared with calcium chloride,

Eleventh, the method does not require additional cost for picking up the agent which had been used for snow removing, in contrast with calcium chloride and sand,

Twelfth, a quantity of snow can be effectively removed only by spraying the heated agent for snow removing, without taking snow away by a car for snow removing,

Thirteenth, since the method uses a physical means for heating, the amount of the composition which is used for snow removing can be minimized, and thus the damage of environment occurred by excessive amount of the agent for snow removing can be reduced and the cost for administrating equipments for snow removing and the cost for snow removing can be considerably cut down.

[Description of Drawings]

FIG. 1 is a photograph showing the degree of recrystallization of formate in the non-chlorinated liquid composition according to the present invention (adding chitosan to aqueous formate solution, right) and in an aqueous formate solution which does not comprises chitosan (left). On the left, the white part indicates occurrence of recrystallization.

FIG. 2 is a graph which compares the method which comprises the step of heating according to the present invention with the method which does not comprise the step of heating and the method which uses heated water. The time for snow removal and the amount of snow removal are indicated.

[Best Mode]

Hereinafter, the present invention will be described in further detail .

The term "snow removing" used herein means elimination of snow lying on road and the like by spraying the present composition for snow removing. The term "ice removing" used herein means the elimination of ice lying on a road and the like. If the object to be eliminated is snow, the present composition can be referred to as a composition for snow removing. If the object to be eliminated is ice, the present composition can be referred to as a composition for ice removing. Thus, the substance to be treated is identical. The terms "snow removing" and "a composition for snow removii used herein should be understood as encompassing the terms "ice removii and "a composition for ice removing". Unless stated otherwise, the terms "snow removing"and "a composition for snow removing" are used hereinafter.

The present invention provides a non-chlorinated liquid composition for snow removing. The composition according to the present invention comprises at least one of organic acid salts selected from the group consisting of alkali metal and alkaline earth metal acetate and alkali metal and alkaline earth metal acetate formate. The organic acid salts can include, for example, potassium acetate, potassium formate, sodium acetate, sodium formate, calcium acetate, calcium formate, magnesium acetate, and magnesium formate.

The composition of the present invention comprises the organic acid salts in an amount of 10 to 60% by weight, preferably 20 to 50% by weight, based on the total amount of the composition. Since acetate and formate have a property of lowering the freezing point of material, they force the freezing point of water lowered and can play a role in removing snow and ice. If the amount of the organic acid salts in the composition is less than 10% by weight, the ability for snow and ice removing is not sufficient. If the amount of the organic acid salts is more than 60% by weight, the composition is not economical and the active ingredients in the liquid composition can be partially recrystallized.

More preferably, the organic acid salts with said composition ratio comprises both of acetate of alkali metal or alkaline earth metal and formate of alkali metal or alkaline earth metal. That is, if the organic acid salts comprises both acetate and formate, they are forced into competition due to dipole effect and similar ion size and thus become approached closely, thereby increasing dipole effect and, thus, builds up colligative properties. Subsequently, the number of solutes per unit area is increased and the phenomenon of freezing point depression becomes more distinct. For example, when potassium acetate (hereinafter, referred to as 'PA') and potassium formate (hereinafter, referred to as 'PF') are mixed with water and chitosan within a range of said mixing ratio, the effect of dipole between PA and PF is enlarged, thereby increasing the colligative properties. Ultimately, the phenomenon of freezing point depression becomes evident. This is due to "the structure which is similar to molten matter, not solubilized matter in a solution", which can not be attributed to a simple mixing for an aqueous solution. In summary, the different organic acid salts become to take a structure which is similar to molten matter in a phase of aqueous solution, and thus the colligative properties is built up.

In an alternative phenomenon, the property of competitive hydrolysis of alkali metal salts by anions in acetate and formate disturbs the development of solid crystals, which provides a mechanism lowering the freezing point of the composition considerably than that expected from the two substances. Generally, when PA and PF are dissolved in water and the dissolved anions are reacted with water, a competitive hydrolysis continues. As a result, the competitive reaction of acetate and formate ions with water changes the crystalline structure of water and thus retards the tendency toward ice.

The metal cation which has a low specific charge is preferred in the organic acid salts. The specific charge of metal cation can play a special role in lowering the freezing point. By a way of explanation, in order to freeze water the movement of water molecule should be minimized so that a crystalline structure is formed. Since potassium cation has a lower specific charge than sodium cation, it shows a lower electric field per unit area than sodium cation and thus its effect on water, which has its own + and charges, is smaller than sodium cation. That is, sodium provides a larger electric field per unit area than potassium and thus inhibits the movement of water molecule more actively than potassium, which makes the water molecule near sodium more readily frozen than that near potassium.

That is, it is understood that a stable physical property for a phase transition is formed, which improves stability, storage and safekeeping.

The non-chlorinated liquid composition of the present invention can further comprise at least one of polysaccharides selected from the group consisting of chitin, chitosan and chitin-chitosan wherein acetyl group is partially removed from chitin. The polysaccharide is preferably chitosan, but chitin-chitosan whose deacetylation is not high can be used, as long as there is no problem in solubility in an aqueous solution. Chitin is also used, if there is no problems which depend on its amount comprised in the composition. Hereinafter, chitosan is expressed as a representative.

In the composition of the present invention, chitosan eliminates the odor of residual organic material in the liquid composition for snow removing, prevents recrystallization, and is effective for adsorbing a small quantity of heavy metals. Chitosan is preferably comprised in an amount of 0.01 to 5% by weight, based on the total amount of the composition. If the amount is less than 0.01% by weight, the effect of chitosan is not sufficient. If the amount is more than 5.0% by weight, the viscosity of the liquid composition for snow removing is increased, which interferes with spraying the composition.

FIG. 1 is a photograph which shows a degree of recrystallization of formate in the non-chlorinated liquid composition according to the present invention (adding chitosan to aqueous formate solution), compared with that of an aqueous formate solution which does not comprise chitosan. Adding chitosan to the composition prevents the organic acid salts of alkali metal or alkaline earth metal from recrystallization and increases storage stability. As shown in FIG. 1, recrystallization occurs in the aqueous formate solution to which chitosan is not added, but not in the aqueous formate solution to which 0.5% by weight of chitosan is added. The formation of formate or acetate crystal in a composition for snow removing greatly reduces storage stability and the ability of snow removing. Further, since the formation of crystal substantially eliminates formate or acetate from the liquid composition for snow removing, the freezing point of the composition rises, which makes it difficult to prevent the molten snow from being refrozen by cold whether after removing snow. Thus, adding chitosan to the non-chlorinated liquid composition for snow removing improves storage stability and the ability of snow removing and also prevents the molten snow from being refrozen, that is, enhances the ability of the composition which maintains the effect of snow removing for a long time.

Preferably, the non-chlorinated liquid composition for snow removing according to the present invention further comprises a corrosion inhibitor. The corrosion inhibitor may include, for example, azole, phosphor carboxylic acid, straight chain carboxylic acid, and phosphoric acid. Typically, the corrosion inhibitor is not limited to specific ones. Particularly, benzotriazole is preferred.

Preferably, the composition of the present invention comprises the corrosion inhibitor in an amount of 0.001 to 3.0% by weight, based on the total amount of the composition. If the amount is less than 0.001% by weight, the effect of snow removing is week and is not sufficient in inhibiting corrosion. If the amount is more than 3.0% by weight, the side effect of oxidation of corrosion inhibitor can occur.

The other component is water. That is, the non-chlorinated liquid composition according to the present invention is an aqueous solution. The composition show a freezing point of -20° C to -70° C, Owing to said low freezing point, the present composition exhibits a good ability of snow and ice removing and prevents the molten snow and ice from being refrozen by cold water.

The method for the preparation of the liquid composition for snow removing having said constitution is not limited to specific ones, but it is preferred that metal acetate or formate is dissolved in water, chitosan and corrosion inhibitor is added thereto and the solution is stirred with a speed of 50 to 1500 rpm at a temperature of 10° C to 30° C.

In another embodiment, the present invention provides a method of removing snow. The present method comprises the steps of heating the non- chlorinated liquid composition to a temperature of 40° C to 120° C and spraying the heated composition on snow or ice. Said temperature was determined from data obtained by experiments which measure the efficacy of snow removing.

In the present method of removing snow, the composition can comprise 10 to 60% by weight of at least one organic acid salt selected from the group consisting of alkali metal and alkaline earth metal acetate and alkali metal and alkaline earth metal acetate formate and a residual amount of water. Further, the composition can further comprise 0.01 to 5% by weight of chitosan. Furthermore, the composition can comprise 0.001 to 3% by weight of corrosion inhibitor.

The present heating method can be adapted to any equipments which can spray a material in a liquid phase. Temperature can be elevated to said range by heating the liquid composition with spray devices having a heating means in water spraying car from which the device can be detached and an automatic spraying system for road, or by adding boiling water to the liquid composit ion.

The present inventors recognized that the heating step in the present method of removing snow brings forth a synergistic effect of snow removing with the ability of the composition per se. The effect of snow removing is not a simple sum of the two factors. The synergistic effect will be illustrated in detail below. Such effect can reduce the amount of the composition used, compared with the calories added, and, ultimately, the effect of snow removing is improved and a good economy, efficacy and productivity in removing snow can be provided. It will be discussed in detail in the following working examples, while comparing the present composition with the typical composition containing calcium chloride.

The synergistic effect will not depend on only the high calorie by heating the composition. In a high temperature, the dissociation constant of PA and PF rises and thus the solute which has been incompletely dissociated becomes completely dissociated and the ionic activity of solute ions is raised, which makes freezing point depression more evident. Since the typical composition for snow removing which comprises calcium chloride is not liquid, the present method cannot be adopted for the composition. Since the typical composition should be dissolved in water, the advantages of calcium chloride, that is, the hygroscopicity of the material and the improvement of melting property by exothermic reaction when absorbs water, cannot be utilized.

The prominent synergistic effect caused by heating the present composition depends on the properties that, first, even though the composition is heated and pressured, the physical property of the composition is not changed and, second, the freezing point is depressed.

The present liquid composition of the present invention is stable without noticeable chemical denaturation, even though the composition is heated to said range of temperature. Further, when mixed with other agents for removing snow such as calcium chloride, the effect of the present composition is not affected. Therefore, the present composition can further comprise other agents, for example, calcium chloride, urea, calcium magnesium acetate (CMA), sodium chloride (salt), nitrate, calcium oxide, PC-IO and the like.

[Mode for Invention] Hereinafter, the present invention is illustrated in detail with reference to the following examples. However, the scope of the present invention is not limited only to these examples.

Example 1

The elimination of the remaining odor of organic material (formic acid) and the inhibition of recrystallization were observed with an aqueous solution of 50% potassium formate to which chitosan (average molecular weight: 20,000, Deacetylation: 80%) was added in an amount of 0.5 by weight and with an aqueous solution of 50% potassium formate which does not contain chitosan. To measure the degree of inhibition of recrystallization, water in the two samples was left volatized at a room temperature in the air so as to derive the recrystallization. After 10 days, the occurrence of recystallization was determined. For the elimination of the remaining odor by chitosan, sensory evaluation for each sample was carried out by five persons (Table 1). As a result, the sample which contains chitosan remarkably reduced the specific odor of formic acid, compared with the sample which does not comprise chitosan. As shown in FIG. 1, the sample which contains chitosan showed considerably improves the crystallization of potassium formate, thereby enhancing the stability of a liquid composition for snow removing. It is considered that the functional group of amine in chitosan molecules is chemically reacted with formate, which reduces the odor due to the volatilization of formic acid and inhibits the crystallization. [Table 1]

Deodorization by the addition of chitosan and inhibition of recrystallization

Example 2

60Og of potassium acetate and 20Og of potassium formate were added to 1,20Og of water and the solution was stirred to prepare an aqueous composition for snow removing. lOOOg of the prepared composition was put in a refrigerator for 1 hour at 5^°C and lOOOg of the remaining composition was heated to 60^°C. For a comparison, lOOOg of pure water was heated to 60^°C. 20Og of each sample was added to 50Og of ice which had been frozen at -20°C . The amount of molten ice was measured at 1, 5, 10, 20, 30 minutes after said addition. The amount of molten ice and the speed of ice melting were compared. Table 2 shows the amount of molten ice with a time elapse for each sample. FIG. 2 also shows the amount of molten ice with a time elapse. [Table 2]

Amount of molten ice with a time elapse (unit: g)

As shown in Table 3, the amount of molten ice was increased within a range of 60 to 110% by heating the liquid composition, compared with the cold composition. In case of potassium acetate, the heated composition showed 110% increment, compared with the composition not heated. Meanwhile, in case of calcium chloride, the heated composition showed 59% increment, compared with the composition not heated. From these results, it is confirmed that when a liquid composition for snow removing is heated, the effect of calcium chloride is far inferior to that of the non-chlorinated composition. The other samples showed 70 to 85% increment in melting ice, when the samples were heated.

Particularly, when the amount of the agent for snow removing is same (Sample Nos. 3 and 5), the chlorinated composition (No. 3) showed an increment in melting ice by 34g, when heated. In contrast, the non- chlorinated composition (No. 5), when heated, showed an increment by 46g. These results indicate that if the composition for snow removing is heated, the non-chlorinated composition shows distinct increment of the amount of molten ice, compared with the chlorinated composition. This confirms that the non-chlorinated composition of the present invention, when heated, exhibits synergistic effect of snow removing, which exceeds expectable effects.

Example 4

The variation of the amount of molten ice according to heating temperature was measured by the liquid composition for snow removing which comprises a mixture of potassium acetate and potassium formate. The amount of the composition, the ice sample, and the cooling temperature of the liquid composition are the same as those in Example 2. The time for melting ice was 10 minutes and the heating temperature was 40, 60, and 80^°C. Table 4 shows the amount of molten ice according to the heating temperature, indicating that the amount of molten ice is increased as the heating temperature is raised.

[Table 4]

Amount of molten ice according to heating temperature (melting time'- 10 minutes)

Example 5

The freezing point of various liquid compositions for snow removing was measured. After incorporating 5Og of each sample to a deep freezer (Manufacturer: ILSHINLAB), while lowering the temperature to -85^°C, the freezing point was observed. The result is shown in Table 5. The non- chlorinated composition for snow removing showed a lower freezing point compared with the chlorinated composition. Also, the addition of chitosan and clay to the composition did not exhibit special effects on a freezing point depression, compared with no addition of chitosan and clay.

[Table 5] Freezing points of compositions for snow removing

Example 6

The freezing point of samples, Sample No. 4 (non-chlorinated) and No. 3 (chlorinated), was measured with a variation of dilution ratio. The result is given in Table 6. It confirms that even though the non-chlorinated composition is diluted by ice melting, the composition shows a lower freezing point than the chlorinated composition; snow and ice can be effectively removed by spraying the non-chlorinated composition in a small amount, compared with the chlorinated composition, and; the non-chlorinated composition has a good ability of preventing the molten snow and ice from being refrozen.

[Table 6]

Freezing point according to dilution ratio 1

Comparative Example 1

The economy, efficacy and productivity of the present method of removing snow were compared with those of the conventional method. The amount of snow removing was measured with the same amount of composition. The samples used in the comparison are as follows:

Non-chlorinated composition (liquid) (potassium acetate: 60Og, potassium formate: 20Og, water: 1,20Og)

Calcium chloride (powder)

Amount of sample: each 1 ton

Price of sample (based on the price of the Office of Public Procurement): non-chlorinated composition (liquid)-600,000 won/ton, calcium chloride (powder)-250,000 won/ton

[Table 7]

Comparison of cost for removing snow of the heated non~chlorinated composition and the conventional chlorinated composition

As shown in Table 7, the present method, which comprises heating the non-chlorinated composition of snow removing and spraying it, is effective in removing snow in a short time and preventing the molten snow from being refrozen. Further, the cost for removing snow by the non-chlorinated composition, when heated, is 20,833 won/km, and thus the present method is more economical than the conventional chlorinated method (31,250 won/km). It cannot be said that the present method is technically superior to the conventional method in consideration of economy at this situation, because materials, equipment and the like used for removing snow can be changed. However, it can be understood that the economy is related to technical superiority. Particularly, it is important evidence showing the technical superiority of the present method that the present method which heats the composition and sprays it is economically far superior to the method which sprays the cold composition.

Specifically, the method of spraying the non-chlorinated liquid composition in a cold state is not economical (43,636 won per km of the distance of snow removal) than the typical method using calcium chloride (31,250 won per km of the distance of snow removal). However, the method of heating the non-chlorinated liquid composition to 60^°C and spraying it (20,833 won per km of the distance of snow removal) is far economical, compared with the cold method of spraying the non-chlorinated composition as well as the typical method using calcium chloride. This outstanding improvement in the aspect of economy indicates that the non-chlorinated liquid composition of the present invention exhibits a synergistic effect by heating the composition, and also shows the improvement of the efficacy and productivity of snow removing by heating the composition.

Further, since the present method of removing snow by heating can eliminate snow in a short time and, thereafter, the molten snow is not refrozen, it provides a good effect on snow removal and maintenance of the molten condition, than the typical method using calcium chloride. Whereas the typical method cannot be applied to deeply accumulated snow, the present method has a wide range of applications in removing deep snow and melting ice road.

Claims

[CLAIMS] [Claim 1]

A non-chlorinated liquid composition for snow or ice removing, which comprises at least one of organic acid salts selected from the group consisting of alkali metal and alkaline earth metal acetate and alkali metal and alkaline earth metal acetate formate, at least one of polysaccharides selected from the group consisting of chitin, chitosan and chitin-chitosan wherein acetyl group is partially removed from chitin, and water. [Claim 2]

The composition of claim 1, wherein the composition comprises 10 to 60% by weight of organic acid salts, 0.01 to 5% by weight of polysaccharides, and the residue amount of water. [Claim 3]

The composition of claim 2, wherein the organic acid salts comprises at least one of acetates of alkali metal and alkaline earth metal and at least one of formates of alkali metal and alkaline earth metal, thereby producing coexistence of acetate and formate ions. [Claim 4]

The composition of any one of claims 1 to 3, wherein the organic acid salts comprises at least one selected from the group consisting of potassium acetate, potassium formate, sodium acetate, sodium formate, calcium acetate, calcium formate, magnesium acetate, and magnesium formate. [Claim 5]

The composition of any one of claims 1 to 3, wherein the composition further comprises 0.001 to 3% by weight of corrosion inhibitor. [Claim 6]

The composition of claim 5, wherein the corrosion inhibitor comprises at least one selected from the group consisting of azole, phosphor carboxylic acid, straight chain carboxylic acid, and phosphoric acid. [Claim 7]

The composition of any one of claims 1 to 3, 5 and 6, wherein the composition has a freezing point of -20°C to -70°C. [Claim 8]

A method of removing snow or ice, which comprises heating a non- chlorinated liquid composition to a temperature of 40°C to 120^°C , wherein the composition comprises at least one of organic acid salts selected from the group consisting of acetates of alkali metal and alkaline earth metal and formates of alkali metal and alkaline earth metal; and spraying the heated composition. [Claim 9]

A method of removing snow or ice, which comprises heating the composition of any one of claims 1 to 7 to a temperature of 40^°C to 120^°C; and spraying the heated composition. [Claim 10]

A method of removing snow or ice, which comprises adding boiling water to the composition of any one of claims 1 to 7; and spraying the heated composition. [Claim 11]

The method of any one of claims 8 to 10, wherein the method further comprises adding the material selected from the group consisting of urea, calcium magnesium acetate, sodium chloride, nitrate, calcium oxide, and calcium chloride to the composition.