Pavement environment-friendly cleaning snow-melting agent and preparation method thereof

Abstract

The invention belongs to the technical field of snow melting and deicing, and discloses an environment-friendly cleaning snow-melting agent for a road surface and a preparation method thereof. The snow-melting agent is composed of 40-80 parts of a chlorine salt solution, 10-20 parts of potassium acetate, 1-10 parts of sodium gluconate, 1-10 parts of urea, 80-100 parts of glycerin and 1-10 parts of a corrosion inhibitor. Wherein the chlorine salt solution comprises 20-40 parts of calcium chloride, 10-20 parts of magnesium chloride and 100 parts of water, and the corrosion inhibitor comprises 1-10 parts of zinc dihydrogen phosphate, 1-10 parts of sodium tungstate, 1-5 parts of thiourea and 1-10 parts of sodium dodecyl benzene sulfonate. The preparation method comprises the steps of raw material pretreatment, mixing and dissolving, corrosion inhibitor adding and the like. The snow melting agent disclosed by the invention has the advantages of good snow melting effect, low corrosivity, small environmental influence, long acting time and low cost, and can reduce the spraying frequency and protect the surrounding environment.

Description

Technical Field

[0001] This invention belongs to the field of snow melting and de-icing technology, and specifically relates to an environmentally friendly road cleaning and snow melting agent and its preparation method. Background Technology

[0002] During the cold winter months in northern my country, snow accumulation on roads can easily lead to traffic inconvenience and safety hazards, making snow melting and de-icing an urgent need. Among existing snow melting methods, manual snow removal is inefficient, and the application of mechanical snow removal is limited. De-icing agents have become the main method due to their ease of use and high efficiency, but traditional de-icing agents have significant drawbacks:

[0003] I. Chemical erosion: De-icing agents, mainly sodium chloride, react with Ca(OH)2 and C3A in concrete, reducing concrete strength, causing road damage, shortening bridge life, and exacerbating soil salinization.

[0004] II. Environmental Hazards: Wastewater from snow melting pollutes groundwater and rivers, harming the health of plants and animals; the released chlorine and bromine gases damage the ozone layer; urea-based snow melting agents can easily cause eutrophication of water bodies.

[0005] III. Usage limitations: Sodium chloride is suitable for freezing points above -22℃, while urea requires freezing points above 10℃, which cannot meet the needs of low temperatures in the north (up to -50℃).

[0006] IV. Ecological damage: It has adverse effects on plants and the respiratory tract, and dust pollution leads to an increase in upper respiratory tract infections.

[0007] Existing de-icing agents have evolved from single chloride salt types to composite anti-corrosion types, but non-chloride types are difficult to popularize due to their high cost. Therefore, developing low-cost, environmentally friendly, and low-corrosion high-efficiency de-icing agents has become an urgent technical problem to be solved. Summary of the Invention

[0008] To overcome the shortcomings of existing technologies, this invention provides an environmentally friendly de-icing agent for road surfaces and its preparation method, so as to achieve the goals of good de-icing effect, low corrosivity, environmental friendliness, long action time and controllable cost.

[0009] The technical solution of this invention:

[0010] This invention provides an environmentally friendly de-icing agent for road surfaces, comprising, by weight:

[0011] Chloride salt solution: 40-80 parts;

[0012] Potassium acetate: 10-20 parts;

[0013] Sodium gluconate: 1-10 parts;

[0014] Urea: 1-10 parts;

[0015] Glycerin: 80-100 parts;

[0016] Corrosion inhibitor: 1-10 parts.

[0017] The chloride salt solution comprises, by weight, the following components:

[0018] Calcium chloride: 20-40 parts;

[0019] Magnesium chloride: 10-20 parts;

[0020] Water: 100 portions.

[0021] The corrosion inhibitor comprises, by weight parts:

[0022] Zinc dihydrogen phosphate: 1-10 parts;

[0023] Sodium tungstate: 1-10 parts;

[0024] Thiourea: 1-5 parts;

[0025] Sodium dodecylbenzenesulfonate: 1-10 parts.

[0026] Preferably, the composition of the de-icing agent by weight is as follows:

[0027] Chloride salt solution: 45-60 parts;

[0028] Potassium acetate: 12-15 parts;

[0029] Sodium gluconate: 3-5 parts;

[0030] Urea: 3-5 parts;

[0031] Glycerin: 80-100 parts;

[0032] Corrosion inhibitor: 3-5 parts.

[0033] Preferably, the chloride salt solution is expressed in parts by weight as follows:

[0034] Calcium chloride: 25-32 parts;

[0035] Magnesium chloride: 15-18 parts;

[0036] Water: 100 portions.

[0037] Preferably, the corrosion inhibitor is expressed in parts by weight as follows:

[0038] Zinc dihydrogen phosphate: 3-7 parts;

[0039] Sodium tungstate: 3-7 parts;

[0040] Thiourea: 2-4 parts;

[0041] Sodium dodecylbenzenesulfonate: 3-7 parts.

[0042] This invention also provides a method for preparing the above-mentioned environmentally friendly de-icing agent for road surfaces, comprising the following steps:

[0043] (1) Weigh each raw material according to the weight proportions;

[0044] (2) After drying and pulverizing potassium acetate, sodium gluconate and urea respectively, they are mixed and stirred evenly to obtain an additive mixture;

[0045] (3) Mix glycerol with chloride salt solution to obtain a mixed solution;

[0046] (4) Add the additive mixture to the mixed solution and stir until completely dissolved to obtain the de-icing agent solution;

[0047] (5) Add corrosion inhibitor to the de-icing agent solution and stir evenly to obtain the environmentally friendly de-icing agent for road surface cleaning.

[0048] Preferably, in steps (4) and (5), the stirring speed is kept constant.

[0049] Preferably, the de-icing agent is a liquid de-icing agent.

[0050] Preferably, the potassium acetate, sodium gluconate, and urea are all pure solid powders.

[0051] The environmentally friendly de-icing agent for road surfaces described in this invention, through a scientifically formulated blend of chloride solution, potassium acetate, sodium gluconate, urea, glycerin, and corrosion inhibitors, offers the following significant advantages over existing technologies:

[0052] I. High snow melting efficiency and wide applicable temperature range

[0053] The synergistic effect of calcium chloride, magnesium chloride, and potassium acetate in the chloride salt solution significantly lowers the freezing point of ice and snow. Combined with the low-temperature stability of glycerol, this lowers the freezing point of the de-icing agent to below -20°C (reaching a minimum of -22.7°C in the examples), far superior to traditional chloride salt de-icing agents (the blank sample had a freezing point of -19°C), making it suitable for the extreme low-temperature environment of -50°C in northern my country. Simultaneously, its relative snow-melting capacity is more than 10% higher than that of traditional chloride salt de-icing agents (reaching a maximum of 112.2% in the examples), enabling rapid melting of snow on roads and shortening snow removal operation time.

[0054] This invention's environmentally friendly de-icing agent for road surfaces uses a combination of calcium chloride and magnesium chloride, and adds glycerin to extend the action time, thus having the advantages of low freezing point, wide operating temperature range, and good de-icing effect. After adding corrosion inhibitors, it solves the shortcomings of ordinary sodium chloride, calcium chloride, and magnesium chloride de-icing agents, such as short de-icing time, need for multiple sprays, and high corrosiveness.

[0055] II. Extremely low corrosiveness, protecting infrastructure.

[0056] Specialized corrosion inhibitors (a compound of zinc dihydrogen phosphate, sodium tungstate, thiourea, and sodium dodecylbenzene sulfonate) effectively inhibit the corrosion of metals and concrete by chloride salts. Experimental data show that the corrosion rate of this de-icing agent on No. 20 carbon steel is only 2.660–4.656 mm / a, which is less than 1 / 20 of that of traditional chloride salt de-icing agents (54.953 mm / a). The corrosion inhibition rate is as high as 91.53%–95.16%, which can significantly reduce damage to bridges, road surface steel reinforcement, and concrete structures, and extend the service life of infrastructure.

[0057] Third, it is highly environmentally friendly and reduces ecological risks.

[0058] The pH value of the snow melting agent is stable between 8.3 and 8.6, which is within the environmental protection standard range of 6.0 to 10.0, thus avoiding the soil acidification or salinization problems caused by traditional snow melting agents.

[0059] The safety of plants is significantly improved. Experiments show that the spraying dosage when lawns show significant damage needs to reach 368-375 ml / m², which is much higher than the 60 ml / m² of traditional chloride salt de-icing agents, thus reducing damage to vegetation and green belts on both sides of the road.

[0060] The composition does not contain any volatile harmful components, thus avoiding the problem of traditional snow melting agents releasing chlorine and bromine gases that damage the ozone layer. In addition, the low urea content can reduce the risk of eutrophication of water bodies.

[0061] The environmentally friendly de-icing agent for road surfaces of this invention contains some trace elements that are beneficial to plant growth, so it can be widely used for de-icing and ice removal on various roads and buildings where there is surrounding vegetation.

[0062] IV. Long duration of action reduces the number of spraying times.

[0063] Glycerin is highly hygroscopic, and its aqueous solution becomes more viscous at low temperatures. After application, it forms a protective film on the surface of ice and snow, extending the snow-melting time. Compared to traditional snow-melting agents that require frequent reapplication, this snow-melting agent can reduce the number of sprays by more than 50%, lowering labor and material costs, while also reducing the cumulative environmental impact of the total amount of snow-melting agent.

[0064] V. Simple preparation and controllable cost

[0065] The raw materials are all industrial-grade and readily available. The preparation process only requires simple steps such as drying, mixing, and dissolving, without the need for special equipment, resulting in high production efficiency. Compared to pure organic de-icing agents (such as potassium acetate alone), the combination of chloride salts and organic components significantly reduces raw material costs while ensuring environmental friendliness, making it suitable for large-scale promotion and application.

[0066] In summary, this snow-melting agent achieves multiple advantages such as "high-efficiency snow melting, low corrosion, environmental protection, long-lasting effect, and low cost," which can not only ensure road traffic safety in winter, but also reduce damage to the ecological environment and infrastructure, thus having significant economic and social benefits.

[0067] The method for preparing environmentally friendly de-icing agent for road surfaces described in this invention, through optimized design of raw material processing, mixing sequence, and process parameters, has the following significant advantages compared to existing de-icing agent preparation technologies:

[0068] I. The process is simple and efficient, suitable for large-scale production.

[0069] The preparation process involves only basic operations such as weighing, drying and pulverizing raw materials, stepwise mixing, and stirring and dissolving. It does not require special processes such as high-temperature calcination or high-pressure reaction, nor does it require specialized precision equipment. Production can be completed using conventional chemical stirring equipment. The steps are seamlessly connected, the production cycle for a single batch is short, and it is easy to achieve continuous industrial production, reducing equipment investment and operating costs.

[0070] II. Uniform component dispersion ensures stable snow melting performance.

[0071] In step (2), potassium acetate, sodium gluconate and urea are dried and pulverized separately to avoid clumping caused by differences in the moisture content of the raw materials, ensuring uniform particle size of the solid additives and laying the foundation for subsequent dissolution and dispersion.

[0072] By adopting a stepwise mixing strategy of "first mixing glycerol and chloride salt solution, then adding the additive mixture, and finally adding corrosion inhibitor", direct reactions between different components can be avoided to prevent precipitation (such as the formation of insoluble salts due to premature contact between chloride salt and corrosion inhibitor). This ensures that each functional component (such as snow-melting component and corrosion inhibitor) is uniformly dispersed in the solution, thereby guaranteeing the batch stability of the snow-melting agent's performance.

[0073] III. Reduce raw material loss and improve the utilization rate of effective ingredients

[0074] The solubility of the dried and pulverized additive mixture is significantly improved. In step (4), it can be quickly and completely dissolved in the glycerol-chloride salt mixture, avoiding the filtration loss of undissolved solid particles. At the same time, the corrosion inhibitor is added in the last step, which can reduce its premature reaction with other components and ensure that the corrosion inhibitor (such as thiourea and sodium tungstate) can play a full role. In the experiment, the corrosion inhibition rate was stable at over 90%, which proves that the utilization rate of the effective components is high.

[0075] IV. The product is in liquid form, which facilitates storage and application.

[0076] The preparation method directly produces liquid de-icing agent without the need for additional granulation or drying steps, reducing process steps and energy consumption. Its liquid form prevents clumping during storage and allows for uniform application using conventional spraying equipment (such as modified road sprinkler trucks). Compared to solid de-icing agents, it is easier to control the dosage, avoiding environmental pollution caused by localized overdose. Furthermore, the larger contact area between the liquid and snow accelerates the melting reaction and improves snow removal efficiency.

[0077] V. Mild operating conditions and high safety

[0078] The entire preparation process is carried out at room temperature and pressure, without the need for high-temperature heating or the use of flammable and explosive reagents, which reduces the safety risks in the production process. At the same time, the raw materials are all low-toxic or non-toxic substances (such as glycerol and sodium gluconate), which have low irritation to the human body during operation, thus reducing protective costs and occupational health hazards.

[0079] In summary, this preparation method is characterized by being "simple, efficient, stable, and low-consumption". It can not only ensure the excellent performance of the environmentally friendly de-icing agent for road surfaces, but also reduce production and application costs, providing process feasibility support for its large-scale promotion. It has significant practical value and economic significance.

[0080] The preferred embodiments of the present invention and their beneficial effects will be further described in detail with reference to specific implementation methods. Attached Figure Description

[0081] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but should not be construed as limiting the invention. In the drawings:

[0082] Figure 1 This is a graph showing the vapor pressure of water and its solutions as a function of temperature. Detailed Implementation

[0083] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0084] This invention provides an environmentally friendly de-icing agent for road surfaces, comprising, by weight:

[0085] Chloride salt solution: 40-80 parts;

[0086] Potassium acetate: 10-20 parts;

[0087] Sodium gluconate: 1-10 parts;

[0088] Urea: 1-10 parts;

[0089] Glycerin: 80-100 parts;

[0090] Corrosion inhibitor: 1-10 parts.

[0091] The chloride salt solution comprises, by weight, the following components:

[0092] Calcium chloride: 20-40 parts;

[0093] Magnesium chloride: 10-20 parts;

[0094] Water: 100 portions.

[0095] The corrosion inhibitor comprises, by weight parts:

[0096] Zinc dihydrogen phosphate: 1-10 parts;

[0097] Sodium tungstate: 1-10 parts;

[0098] Thiourea: 1-5 parts;

[0099] Sodium dodecylbenzenesulfonate: 1-10 parts.

[0100] Preferably, the composition of the de-icing agent by weight is as follows:

[0101] Chloride salt solution: 45-60 parts;

[0102] Potassium acetate: 12-15 parts;

[0103] Sodium gluconate: 3-5 parts;

[0104] Urea: 3-5 parts;

[0105] Glycerin: 80-100 parts;

[0106] Corrosion inhibitor: 3-5 parts.

[0107] Preferably, the chloride salt solution is expressed in parts by weight as follows:

[0108] Calcium chloride: 25-32 parts;

[0109] Magnesium chloride: 15-18 parts;

[0110] Water: 100 portions.

[0111] Preferably, the corrosion inhibitor is expressed in parts by weight as follows:

[0112] Zinc dihydrogen phosphate: 3-7 parts;

[0113] Sodium tungstate: 3-7 parts;

[0114] Thiourea: 2-4 parts;

[0115] Sodium dodecylbenzenesulfonate: 3-7 parts.

[0116] This invention also provides a method for preparing the above-mentioned environmentally friendly de-icing agent for road surfaces, comprising the following steps:

[0117] (1) Weigh each raw material according to the weight proportions;

[0118] (2) After drying and pulverizing potassium acetate, sodium gluconate and urea respectively, they are mixed and stirred evenly to obtain an additive mixture;

[0119] (3) Mix glycerol with chloride salt solution to obtain a mixed solution;

[0120] (4) Add the additive mixture to the mixed solution and stir until completely dissolved to obtain the de-icing agent solution;

[0121] (5) Add corrosion inhibitor to the de-icing agent solution and stir evenly to obtain the environmentally friendly de-icing agent for road surface cleaning.

[0122] Preferably, in steps (4) and (5), the stirring speed is kept constant.

[0123] Preferably, the de-icing agent is a liquid de-icing agent.

[0124] Preferably, the potassium acetate, sodium gluconate, and urea are all pure solid powders.

[0125] 1. The formula of this de-icing agent

[0126] Table 1 below lists five examples and a blank sample of the de-icing agent, with the components listed in parts by weight:

[0127] Table 1 Formula composition blank sample Example 1 Example 2 Example 3 Example 4 Example 5 Calcium chloride 40 25 27.4 29.7 31.3 32 Magnesium chloride 20 15 15.7 16.9 17.5 18 Potassium acetate / 12 13.4 13.9 14.2 15 Sodium gluconate / 3 3.6 4.1 4.7 5 Urea / 3 3.4 4 4.6 5 glycerin / 80 83 87 96 100 water 100 100 100 100 100 100 Zinc dihydrogen phosphate / 3 6 7 7 7 Sodium tungstate / 3 4 5 5 7 Thiourea / 2 3 3 3 4 Sodium dodecylbenzenesulfonate / 3 4 4 6 7

[0128] 2. Freezing point test

[0129] A certain amount of de-icing agent solution was taken to prepare an aqueous solution with a concentration of 250 g / L. After inserting a thermometer, the entire system was placed in a freezing environment. The temperature indicated by the thermometer in the solution was observed and recorded. The freezing point data of each sample were obtained, and the results are summarized as follows (see Table 2):

[0130] Table 2 type Freezing point (°C) blank sample -19 Example 1 -22.2 Example 2 -22.6 Example 3 -22.4 Example 4 -21.9 Example 5 -22.7

[0131] The results in the table show that the prepared environmentally friendly de-icing agent solution for road surfaces has a lower freezing point than traditional chloride de-icing agents, reaching below -20℃, and therefore has a wider operating temperature range.

[0132] 3. De-icing rate detection

[0133] According to the test method for snow melting and de-icing capacity in the national standard for road de-icing agents, the snow melting capacity of the prepared snow melting agent solutions in each embodiment was tested and compared with the prepared blank sample solution.

[0134] Experimental method: Take several 1000mL beakers, add 300mL of water to each, place them in a freezer to freeze, weigh and record the mass of each beaker and ice block. Prepare a de-icing agent solution with a concentration of 250g / L, take 50mL and pour it into each ice beaker. After 1 hour, weigh the remaining ice block in the beaker and compare the data with the blank sample.

[0135] Calculate snow melting and ice clearing capacity using the following steps:

[0136] a) The relative snow melting and ice-melting capacity W1 is calculated using the following formula:

[0137]

[0138] In the formula:

[0139] m0 — Mass of the beaker and ice before adding the de-icing agent test solution, in g;

[0140] m1——The mass of the beaker and remaining ice after 0.5 hours of adding the de-icing agent test solution and emptying the liquid in the beaker, in grams;

[0141] m0'——The mass of the beaker and ice before adding the chloride solution, in grams;

[0142] m1'——The mass of the beaker and remaining ice after 0.5 hours of adding chloride salt solution and emptying the beaker of liquid, in grams.

[0143] b) The arithmetic mean of two parallel measurements shall be taken as the measurement result; the absolute difference between the two parallel measurements shall not exceed 5%.

[0144] The calculation results are summarized below.

[0145] Table 3 type Snow melting capacity compared with the blank sample (%) blank sample 1 Example 1 112.1 Example 2 111.5 Example 3 110.9 Example 4 111.6 Example 5 112.2

[0146] The data in the table show that, under the same conditions, the ice-melting capacity of each embodiment of the prepared environmentally friendly de-icing agent for road surfaces is greater than that of the blank sample, which meets the national standards.

[0147] 4. Corrosion test of carbon steel

[0148] The test was conducted according to the rotating hanging plate method described in national standard DB11 / T161-2012. The specific experiment is as follows:

[0149] (1) Select a rectangular No. 20 carbon steel sheet (GB / T699) with the following dimensions: 5mm × 2.5mm × 0.2mm and a surface area of ​​28mm². 2 Before the experiment, the steel sheet surface was cleaned of grease as required, dried in a desiccator, and then the weight of the steel sheet was measured and recorded.

[0150] (2) Prepare a de-icing agent solution and a blank sample solution with a concentration of 250 g / L. Take 6 1 L beakers and pour them into the solution.

[0151] (3) The treated steel sheets were suspended in the prepared solution with nylon ropes and soaked for 48 hours. After being removed and cleaned, they were weighed and recorded again. The data were compared with the blank sample. The results are as follows.

[0152] The specific corrosion rate is determined based on the corrosion rate calculation formula, as follows:

[0153]

[0154] In the formula:

[0155] X — Corrosion rate of the specimen, mm / a;

[0156] W1—Mass of the test piece before the experiment, in g;

[0157] W2—Mass of the test piece after the test, in grams;

[0158] 8760 – Total number of hours in a year;

[0159] A – Surface area of ​​the test piece, cm² 2 ;

[0160] T—Experimental time, in hours;

[0161] D – Density of the experimental material, g / cm³ 3 .

[0162] In addition, the formula for calculating the corrosion inhibition rate X2 as a percentage is:

[0163]

[0164] In the formula:

[0165] X0 — Corrosion rate of the blank sample, mm / a;

[0166] X1 — Corrosion rate for each embodiment, mm / a.

[0167] After calculating the experimental data, the results are summarized in Table 4:

[0168] Table 4 type Mass before experiment (g) Mass (g) after the test Poor quality (g) Corrosion rate (mm / a) Sustained-release rate (%) blank sample 19.8886 19.8225 0.0661 54.953 / Example 1 19.8956 19.8924 0.0032 2.660 95.16 Example 2 19.7894 19.7848 0.0046 3.824 93.04 Example 3 19.5876 19.5834 0.0042 3.492 93.65 Example 4 19.6971 19.6915 0.0056 4.656 91.53 Example 5 19.8573 19.8534 0.0039 3.242 94.10

[0169] The data in the table show that, after adding corrosion inhibitors, compared with the blank sample, the prepared environmentally friendly de-icing agent for road surface cleaning has lower corrosivity to standard carbon steel sheets, which is basically about 1 / 20 of that of ordinary chloride de-icing agents, and the slow release rate is basically over 90%, which is very effective.

[0170] 5. pH test of de-icing agent

[0171] According to the relevant provisions in the national standard GB / T23851-2009, a de-icing agent solution with a concentration of 250 g / L was prepared, its pH value was measured, and compared with a blank sample. The data are recorded in Table 5:

[0172] Table 5 type PH blank sample 7.0 Example 1 8.5 Example 2 8.4 Example 3 8.3 Example 4 8.5 Example 5 8.6

[0173] As can be seen from the data in the table, the pH values ​​measured in each embodiment are all between 6.0 and 10, which meets the standard requirements.

[0174] 6. Plant damage test

[0175] Following the test methods in the national standard for road de-icing and snow-melting agents, a plant tolerance experiment was conducted on the prepared snow-melting agent samples. The specific process was as follows: a 6×4m... 2 Ordinary lawns were used as the experimental subjects, and the experiment was conducted once a week at a dose of 50 ml / m². 2 The periodic spraying experiment was conducted, and the spraying dosage when significant damage to the lawn was observed and recorded. The data were compared with that of the control sample. The results are shown in Table 6:

[0176] Table 6 type Spray dose (ml / m 2 )]]> blank sample 60 Example 1 371 Example 2 375 Example 3 368 Example 4 374 Example 5 370

[0177] The data in the table show that, under the same experimental conditions, the prepared environmentally friendly de-icing agent for road surfaces is less harmful to plants than the blank sample (i.e., ordinary chloride de-icing agent). It is a low-corrosion environmentally friendly de-icing agent that can effectively reduce damage to roadside plants during the de-icing agent spraying process.

[0178] The working principle of this environmentally friendly de-icing agent for road surfaces is as follows:

[0179] The main reason why de-icing agents can melt snow and ice is that they lower the freezing point of ice and snow. The freezing point is the temperature at which a substance exists in both liquid and solid states in equilibrium, allowing them to coexist. When de-icing agents are applied to icy and snowy roads, the hygroscopic solid components in the agent quickly absorb moisture from the air, causing deliquescence and forming a small amount of water on the surface of the ice and snow. Under the impact of vehicle wheels, the de-icing agent gradually becomes a solution.

[0180] If a small amount of solute dissolves in ice water to form a solution, the surface area of ​​water in contact with air decreases because many positions of the surface water molecules are occupied by the volatile solute (or salt), causing the water vapor pressure to drop. Figure 1 At 0°C (273K), at point F, the vapor pressure of ice is higher than that of the aqueous solution, and ice continuously transforms into water vapor. Simultaneously, water vapor continuously condenses into water and enters the solution. Therefore, the solution cannot freeze at point F (273K), while the ice can melt. As the temperature decreases, the vapor pressure of ice decreases along line FE. When the temperature drops to point E, the vapor pressures of ice and the aqueous solution become equal, allowing ice and the aqueous solution to coexist. Therefore, point E is the freezing point (or solidification point) of the aqueous solution.

[0181] Based on the above analysis, it can be seen that the vapor pressures of the solid (ice and snow) and liquid (the de-icing agent that melts into liquid) phases are unequal, and the two phases cannot coexist. One phase must transform into the other. If the vapor pressure of the solid phase is greater than that of the liquid phase, the solid phase will transform into the liquid phase, i.e., the solid melts; conversely, the liquid phase will transform into the solid phase. At this time, the vapor pressure of the resulting solution is lower than that of the ice and snow, and the ice and snow begin to melt. As this process expands, the reaction rate accelerates, micro-cracks appear on the ice and snow surface, producing a popping sound, forming large-area cracks, gradually expanding from localized melting to complete melting, exposing the road surface.

[0182] The environmentally friendly de-icing agent for road surfaces described in this invention, through a scientifically formulated blend of chloride solution, potassium acetate, sodium gluconate, urea, glycerin, and corrosion inhibitors, offers the following significant advantages over existing technologies:

[0183] I. High snow melting efficiency and wide applicable temperature range

[0184] The synergistic effect of calcium chloride, magnesium chloride, and potassium acetate in the chloride salt solution significantly lowers the freezing point of ice and snow. Combined with the low-temperature stability of glycerol, this lowers the freezing point of the de-icing agent to below -20°C (reaching a minimum of -22.7°C in the examples), far superior to traditional chloride salt de-icing agents (the blank sample had a freezing point of -19°C), making it suitable for the extreme low-temperature environment of -50°C in northern my country. Simultaneously, its relative snow-melting capacity is more than 10% higher than that of traditional chloride salt de-icing agents (reaching a maximum of 112.2% in the examples), enabling rapid melting of snow on roads and shortening snow removal operation time.

[0185] This invention's environmentally friendly de-icing agent for road surfaces uses a combination of calcium chloride and magnesium chloride, and adds glycerin to extend the action time, thus having the advantages of low freezing point, wide operating temperature range, and good de-icing effect. After adding corrosion inhibitors, it solves the shortcomings of ordinary sodium chloride, calcium chloride, and magnesium chloride de-icing agents, such as short de-icing time, need for multiple sprays, and high corrosiveness.

[0186] II. Extremely low corrosiveness, protecting infrastructure.

[0187] Specialized corrosion inhibitors (a compound of zinc dihydrogen phosphate, sodium tungstate, thiourea, and sodium dodecylbenzene sulfonate) effectively inhibit the corrosion of metals and concrete by chloride salts. Experimental data show that the corrosion rate of this de-icing agent on No. 20 carbon steel is only 2.660–4.656 mm / a, which is less than 1 / 20 of that of traditional chloride salt de-icing agents (54.953 mm / a). The corrosion inhibition rate is as high as 91.53%–95.16%, which can significantly reduce damage to bridges, road surface steel reinforcement, and concrete structures, and extend the service life of infrastructure.

[0188] Third, it is highly environmentally friendly and reduces ecological risks.

[0189] The pH value of the snow melting agent is stable between 8.3 and 8.6, which is within the environmental protection standard range of 6.0 to 10.0, thus avoiding the soil acidification or salinization problems caused by traditional snow melting agents.

[0190] The safety of plants is significantly improved. Experiments show that the spraying dosage when lawns show significant damage needs to reach 368-375 ml / m², which is much higher than the 60 ml / m² of traditional chloride salt de-icing agents, thus reducing damage to vegetation and green belts on both sides of the road.

[0191] The composition does not contain any volatile harmful components, thus avoiding the problem of traditional snow melting agents releasing chlorine and bromine gases that damage the ozone layer. In addition, the low urea content can reduce the risk of eutrophication of water bodies.

[0192] IV. Long duration of action reduces the number of spraying times.

[0193] Glycerin is highly hygroscopic, and its aqueous solution becomes more viscous at low temperatures. After application, it forms a protective film on the surface of ice and snow, extending the snow-melting time. Compared to traditional snow-melting agents that require frequent reapplication, this snow-melting agent can reduce the number of sprays by more than 50%, lowering labor and material costs, while also reducing the cumulative environmental impact of the total amount of snow-melting agent.

[0194] V. Simple preparation and controllable cost

[0195] The raw materials are all industrial-grade and readily available. The preparation process only requires simple steps such as drying, mixing, and dissolving, without the need for special equipment, resulting in high production efficiency. Compared to pure organic de-icing agents (such as potassium acetate alone), the combination of chloride salts and organic components significantly reduces raw material costs while ensuring environmental friendliness, making it suitable for large-scale promotion and application.

[0196] In summary, this snow-melting agent achieves multiple advantages such as "high-efficiency snow melting, low corrosion, environmental protection, long-lasting effect, and low cost," which can not only ensure road traffic safety in winter, but also reduce damage to the ecological environment and infrastructure, thus having significant economic and social benefits.

[0197] The method for preparing environmentally friendly de-icing agent for road surfaces described in this invention, through optimized design of raw material processing, mixing sequence, and process parameters, has the following significant advantages compared to existing de-icing agent preparation technologies:

[0198] I. The process is simple and efficient, suitable for large-scale production.

[0199] The preparation process involves only basic operations such as weighing, drying and pulverizing raw materials, stepwise mixing, and stirring and dissolving. It does not require special processes such as high-temperature calcination or high-pressure reaction, nor does it require specialized precision equipment. Production can be completed using conventional chemical stirring equipment. The steps are seamlessly connected, the production cycle for a single batch is short, and it is easy to achieve continuous industrial production, reducing equipment investment and operating costs.

[0200] II. Uniform component dispersion ensures stable snow melting performance.

[0201] In step (2), potassium acetate, sodium gluconate and urea are dried and pulverized separately to avoid clumping caused by differences in the moisture content of the raw materials, ensuring uniform particle size of the solid additives and laying the foundation for subsequent dissolution and dispersion.

[0202] By adopting a stepwise mixing strategy of "first mixing glycerol and chloride salt solution, then adding the additive mixture, and finally adding corrosion inhibitor", direct reactions between different components can be avoided to prevent precipitation (such as the formation of insoluble salts due to premature contact between chloride salt and corrosion inhibitor). This ensures that each functional component (such as snow-melting component and corrosion inhibitor) is uniformly dispersed in the solution, thereby guaranteeing the batch stability of the snow-melting agent's performance.

[0203] III. Reduce raw material loss and improve the utilization rate of effective ingredients

[0204] The solubility of the dried and pulverized additive mixture is significantly improved. In step (4), it can be quickly and completely dissolved in the glycerol-chloride salt mixture, avoiding the filtration loss of undissolved solid particles. At the same time, the corrosion inhibitor is added in the last step, which can reduce its premature reaction with other components and ensure that the corrosion inhibitor (such as thiourea and sodium tungstate) can play a full role. In the experiment, the corrosion inhibition rate was stable at over 90%, which proves that the utilization rate of the effective components is high.

[0205] IV. The product is in liquid form, which facilitates storage and application.

[0206] The preparation method directly produces liquid de-icing agent without the need for additional granulation or drying steps, reducing process steps and energy consumption. Its liquid form prevents clumping during storage and allows for uniform application using conventional spraying equipment (such as modified road sprinkler trucks). Compared to solid de-icing agents, it is easier to control the dosage, avoiding environmental pollution caused by localized overdose. Furthermore, the larger contact area between the liquid and snow accelerates the melting reaction and improves snow removal efficiency.

[0207] V. Mild operating conditions and high safety

[0208] The entire preparation process is carried out at room temperature and pressure, without the need for high-temperature heating or the use of flammable and explosive reagents, which reduces the safety risks in the production process. At the same time, the raw materials are all low-toxic or non-toxic substances (such as glycerol and sodium gluconate), which have low irritation to the human body during operation, thus reducing protective costs and occupational health hazards.

[0209] In summary, this preparation method is characterized by being "simple, efficient, stable, and low-consumption". It can not only ensure the excellent performance of the environmentally friendly de-icing agent for road surfaces, but also reduce production and application costs, providing process feasibility support for its large-scale promotion. It has significant practical value and economic significance.

[0210] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A road surface environmentally friendly cleaning and de-icing agent, characterized in that, By weight, its composition includes: The mixture consists of 40-80 parts chloride salt solution, 10-20 parts potassium acetate, 1-10 parts sodium gluconate, 1-10 parts urea, 80-100 parts glycerin, and 1-10 parts corrosion inhibitor.

2. The environmentally friendly de-icing agent for road surface cleaning according to claim 1, characterized in that, The chloride salt solution comprises, by weight, 20-40 parts calcium chloride, 10-20 parts magnesium chloride, and 100 parts water.

3. The environmentally friendly de-icing agent for road surface cleaning according to claim 1, characterized in that, The corrosion inhibitor comprises, by weight, 1-10 parts of zinc dihydrogen phosphate, 1-10 parts of sodium tungstate, 1-5 parts of thiourea, and 1-10 parts of sodium dodecylbenzenesulfonate.

4. The environmentally friendly de-icing agent for road surface cleaning according to claim 1, characterized in that, By weight, its composition includes: The mixture consists of 45-60 parts chloride salt solution, 12-15 parts potassium acetate, 3-5 parts sodium gluconate, 3-5 parts urea, 80-100 parts glycerin, and 3-5 parts corrosion inhibitor.

5. The environmentally friendly de-icing agent for road surface cleaning according to claim 1, characterized in that, The chloride salt solution comprises, by weight, 25-32 parts calcium chloride, 15-18 parts magnesium chloride, and 100 parts water.

6. The environmentally friendly de-icing agent for road surface cleaning according to claim 1, characterized in that, The corrosion inhibitor comprises, by weight, 3-7 parts zinc dihydrogen phosphate, 3-7 parts sodium tungstate, 2-4 parts thiourea, and 3-7 parts sodium dodecylbenzenesulfonate.

7. A method for preparing the environmentally friendly de-icing agent for road surface cleaning according to any one of claims 1 to 6, characterized in that, Includes the following steps: (1) Weigh each raw material according to the weight proportions; (2) After drying and pulverizing potassium acetate, sodium gluconate and urea respectively, they are mixed and stirred evenly to obtain an additive mixture; (3) Mix glycerol with chloride salt solution to obtain a mixed solution; (4) Add the additive mixture to the mixed solution and stir until completely dissolved to obtain the de-icing agent solution; (5) Add corrosion inhibitor to the de-icing agent solution and stir evenly to obtain the environmentally friendly de-icing agent for road surface cleaning.

8. The method for preparing the environmentally friendly de-icing agent for road surface cleaning according to claim 7, characterized in that, In steps (4) and (5), the stirring speed is kept constant.

9. The method for preparing the environmentally friendly de-icing agent for road surface cleaning according to claim 7, characterized in that, The environmentally friendly de-icing agent for road surface cleaning is a liquid de-icing agent.

10. The method for preparing the environmentally friendly de-icing agent for road surface cleaning according to claim 7, characterized in that, The potassium acetate, sodium gluconate, and urea are all pure solid powders.

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