Preparation and use method of water-reducing anti-freezing agent for railway coal open wagon transportation

Abstract

The invention discloses a preparation and use method of a water-reducing anti-freezing agent for railway coal open wagon transportation, and the water-reducing anti-freezing agent for railway coal open wagon transportation comprises the following raw materials in percentage by mass: 30-40% of stearic acid, 30-40% of ethylene glycol, 5% of calcium chloride, 5-10% of polycarboxylic acid, 1-2% of an additive and the balance of deionized water. The anti-freezing agent has good anti-freezing performance, can meet the requirements of coal export, does not corrode production and transportation equipment, does not generate acid gas in the coal combustion process, and meets the national environmental protection requirements; the anti-freezing agent can be diluted according to field use conditions, is convenient and rapid, has high efficiency, and has the characteristics of simplicity, convenience, convenient operation, reliable data and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of coal transportation, and particularly relates to a preparation and use method of a water-reducing and anti-freezing agent for railway coal gondola transportation. Background Art

[0002] Coal is an important basic energy source and industrial raw material in China, and is widely used in fields such as metallurgy, chemical industry, building materials, and thermal power generation. Due to the uneven distribution of China's coal production and use in terms of regions, the coal sources of coal-using enterprises often need to be transported by railway. With the continuous improvement of the coal washing rate, the moisture content in the washed coal is generally between 6.5% and 20%. In winter in the north, the outdoor temperature generally ranges from -30°C to -10°C. During the storage or transportation of coal in winter, water will gradually penetrate to the bottom of the coal seam and freeze with the carriage. The frozen coal is difficult to load and unload during transportation, causing problems such as train blocking and port congestion. The thickness of the frozen coal is generally about 400 mm, and in severe cases, even the whole train freezes. The main reason for the freezing and sticking phenomenon during coal transportation is that the carriage has a strong physical and chemical adhesion effect on the transported coal, resulting in the coal sticking to each other and adsorbing on the surface of the carriage, and the contained moisture condenses into ice in a low-temperature environment, further aggravating the adhesion of coal powder particles on the inner wall and bottom of the carriage. Therefore, the unloading operation is very difficult.

[0003] Many methods have been used at home and abroad to solve the problem of coal freezing during unloading, such as methods like vibration, heating, oiling and waxing, and adding chlorides to coal. However, these methods have high costs and poor effects, and the car body and coal quality will be affected. Therefore, researching and using anti-freezing agents has become the mainstream trend in the field of coal anti-freezing in recent years. Anti-freezing agents are convenient to use, not restricted by the site, have low energy consumption and remarkable effects. At present, the vast majority of coal enterprises in China choose to use anti-freezing agents mainly composed of calcium chloride to solve the problems of frozen coal and frozen cars. However, calcium chloride-based coal anti-freezing agents have low adhesion. When the use concentration is low, the anti-freezing effect on coal is not good. When using a higher concentration of calcium chloride anti-freezing agent, a large amount of chlorine elements will be introduced, which will corrode the storage and spraying equipment and the train carriage. During the coal combustion process, chlorine will be converted into hydrogen chloride, which will have an impact on the environment. Summary of the Invention

[0004] In order to solve the above problems, the present invention proposes a preparation and use method of a water-reducing and anti-freezing agent for railway coal gondola transportation.

[0005] The water-reducing and anti-freezing agent for railway coal gondola transportation of the present invention comprises the following raw materials in mass percentages: 30-40% of stearic acid, 30-40% of ethylene glycol, 5% of calcium chloride, 5-10% of polycarboxylic acid, 1-2% of an additive, and the balance is deionized water.

[0006] The water-reducing and anti-freezing agent for railway coal gondola car transportation of the present invention comprises raw materials in the following mass percentages: 40% of stearic acid, 40% of ethylene glycol, 5% of calcium chloride, 10% of polycarboxylic acid, 1% of additive, and the balance being deionized water.

[0007] The additive comprises malonic acid, anti-corrosion and scale inhibition essence, and triethanolamine, and by mass percentage, malonic acid: anti-corrosion and scale inhibition essence: triethanolamine = 1:1:1.

[0008] The preparation method of the water-reducing and anti-freezing agent for railway coal gondola car transportation of the present invention comprises the following steps:

[0009] a. Solution preparation: Add calcium chloride and the additive into deionized water to make a standby solution;

[0010] b. Raw material preparation: Mix stearic acid and ethylene glycol, heat on a sand bath, and keep warm until the solid is dissolved, thus making the main material;

[0011] c. Auxiliary material addition: Add polycarboxylic acid into the prepared main material and stir. Wait until the temperature drops to room temperature, thus making the main mixture;

[0012] d. Mixing process: Pour the standby solution prepared in a into the main mixture and stir evenly to obtain the finished water-reducing and anti-freezing agent.

[0013] The temperature of the sand bath is 50 - 60°C.

[0014] Stearic acid (C 18 H 16 O2) is a long-chain fatty acid, which mainly plays three roles: thickening, enhancing surface activity, and corrosion inhibition. As a thickening agent and surfactant, it can increase the viscosity of the anti-freezing agent, making it easier to adhere to the surface of coal, thus providing better anti-freezing and anti-sticking protection. After stearic acid is dissolved in water, it will form a protective film on the surface of coal, reducing the direct contact between coal and the carriage, and preventing coal from freezing on the carriage. As a corrosion inhibitor, it can form a dense protective film on the metal surface of the inner wall of the carriage, preventing the metal from reacting chemically with other components in the anti-freezing material, thus slowing down the corrosion of the metal. This is because the long carbon chain structure in the stearic acid molecule can be arranged in an orderly manner on the metal surface, with the hydrophobic carbon chain part facing outward, forming a physical barrier to hinder the contact between corrosive substances and the metal.

[0015] Ethylene glycol (C2H6O2) mainly plays the role of lowering the freezing point temperature. It has a relatively low freezing point. When mixed with water, it can lower the freezing point of water, thus playing an antifreeze role. This is based on the colligative properties principle of solutions. When ethylene glycol dissolves in water, the solute particles (ethylene glycol molecules) in the solution will interfere with the orderly arrangement of water molecules, causing water to freeze into ice at a lower temperature. The freezing point of its aqueous solution will decrease as the concentration of ethylene glycol increases. It protects the normal transportation of coal in cold environments by lowering the freezing point of water and preventing water from freezing at low temperatures. Its mechanism of action can be simplified to the colligative properties of solutions, that is, the freezing point depression of the solution is proportional to the molar concentration of the solute:

[0016] ΔT f =K f ·m

[0017] Where, ΔT f is the temperature of freezing point depression, K f is the freezing point depression constant of the solvent, and m is the molar concentration of the solute.

[0018] The main functions of calcium chloride (CaCl2) are to lower the freezing point temperature and hygroscopicity. It can lower the freezing point of the solution. It is a strong electrolyte. After calcium chloride dissolves in water, it will release a large number of calcium ions (Ca 2 +) and chloride ions (Cl-). These ions will increase the number of particles in the solution. According to the colligative properties of dilute solutions, the freezing point of the solution will be further lowered, thus enhancing the antifreeze performance of the antifreeze.

[0019] CaCl2→Ca 2+ +2Cl -

[0020] At the same time, calcium chloride also has a certain hygroscopicity, which can reduce the moisture content in the pulverized coal, helping to reduce the possibility of freezing of pulverized coal with moisture and maintaining the performance stability of other antifreeze materials.

[0021] However, calcium chloride may corrode metals, so corrosion inhibitors (stearic acid) usually need to be added.

[0022] Polycarboxylic acid contains a large number of carboxyl hydrophilic groups (-COOH), lipophilic groups (R-), and anionic groups such as sulfonic acid groups (-SO3H) in its molecular structure, and mainly plays a water-reducing role. After these groups dissociate in water, the molecule becomes negatively charged. When adsorbed on the surface of pulverized coal particles, the pulverized coal particles also carry a negative charge. Due to the electrostatic repulsion between like charges, the distance between pulverized coal particles increases, preventing the aggregation of pulverized coal particles, thus reducing the freezing and particle adhesion caused by capillary water between pulverized coal particles. It increases the voids between particles, helping the aggregated water to drain quickly.

[0023] Polycarboxylic acid can effectively adsorb on the surface of coal powder particles, forming a uniform hydration film with a certain thickness, which changes the interaction force between coal powder particles and inhibits the agglomeration phenomenon between particles. This adsorption not only improves the dispersibility of coal powder particles but also reduces the water content in the coal powder. In addition, polycarboxylic acid can also reduce the surface tension of water, making it easier for water to separate from the surface of coal powder, further promoting the release of moisture. It better prevents the interaction between particles and the freezing of particles and moisture, thereby improving the fluidity of coal powder.

[0024] The dissociation of polycarboxylic acid (PAA) can be expressed as:

[0025] PAA→PAA - +H +

[0026] The electrostatic repulsion process can be described as:

[0027] Coal+PAA - →Coal-PAA -

[0028] Malonic acid (C3H4O4) mainly plays the role of regulating the pH value and assisting in corrosion inhibition. It is an organic acid with certain acidity, which can adjust the pH value of the water-reducing and anti-freezing material within a suitable range to prevent the metal from being corroded due to an overly acidic or alkaline environment. At the same time, the carboxyl group in the malonic acid molecule can undergo a certain chemical reaction with the metal surface to form a metal carboxylate film with a certain protective effect, further enhancing the corrosion inhibition effect. It hinders and delays the contact between corrosive substances and the metal on the inner wall of the carriage.

[0029] The anti-corrosion and scale-inhibiting essence is a composite additive, usually containing various components with corrosion inhibition and scale inhibition functions. It can form a protective film on the metal surface to prevent metal corrosion. At the same time, it can also inhibit the formation of scale by metal ions such as calcium and magnesium in water, ensuring that the anti-freezing material maintains good performance during long-term use and reducing damage to equipment. It hinders and delays the contact between corrosive substances and the metal on the inner wall of the carriage.

[0030] Triethanolamine (C6H 15 NO3) mainly acts as a pH regulator and an auxiliary corrosion inhibitor in the antifreeze. It is an organic base that can neutralize the acidic substances that may be generated in the antifreeze and maintain the pH value of the solution within the alkaline range, thereby inhibiting metal corrosion. The hydroxyl group and amino group in the triethanolamine molecule can undergo chemical adsorption with the metal surface to form a dense protective film, enhancing the corrosion inhibition effect. In addition, triethanolamine can also form stable complexes with some metal ions, further preventing the corrosion and precipitation of metal ions.

[0031] After the above components are mixed in the designed proportions, by changing the properties of the solution, the water content in the pulverized coal is reduced, the protective film of the pulverized coal particles is increased, and the fluidity between the pulverized coal particles is enhanced (polycarboxylic acid and calcium chloride), thereby further improving the anti-freezing effect (ethylene glycol and calcium chloride) and hindering and delaying the contact between corrosive substances and the metal on the inner wall of the carriage (stearic acid, malonic acid, anti-corrosion and scale inhibitor, and triethanolamine).

[0032] The loading method of the water-reducing and anti-freezing agent for railway coal gondola cars of the present invention includes the following steps:

[0033] S1. Check the integrity of the equipment;

[0034] S2. Apply the water-reducing and anti-freezing agent to the bottom and sides inside the gondola car;

[0035] S3. Use the three-part method, that is, a method of filling in three steps, to fill the pulverized coal in the gondola car. For each layer of coal loaded, spray a layer of anti-freezing agent;

[0036] S4. According to the depth to be measured, insert the temperature sensor to ensure good contact between the temperature sensor and the medium to obtain accurate temperature data;

[0037] S5. Connect the temperature sensor to the data acquisition controller and turn on the power;

[0038] S6. View the coal seam temperature data in real time through the display screen of the data acquisition controller. The user can set the required alarm threshold to ensure that the system can issue an alarm in time when the temperature is abnormal;

[0039] S7. After the measurement is completed, pull out the temperature sensor to avoid damaging the coal seam;

[0040] S8. Unload the coal in the gondola car and weigh and record the mass of the unloaded coal;

[0041] S9. Data recording, record the measured temperature data for subsequent analysis and reference.

[0042] In the above three-part method, a layer of anti-freezing agent is also sprayed on the top of the outermost layer of the pulverized coal.

[0043] There are multiple temperature sensors. The multiple temperature sensors are evenly distributed in the pulverized coal inside the gondola car, and the multiple temperature sensors are respectively inserted into three different depths of the pulverized coal.

[0044] The beneficial effects of the present invention are as follows: The antifreeze of the present invention has good antifreeze performance, which can meet the requirements of coal exports. At the same time, it will not corrode the production and transportation equipment, and no acidic gases will be generated during the coal combustion process, meeting the national environmental protection requirements; the antifreeze of the present invention can be diluted according to the on-site use conditions, which is convenient, fast and efficient, and has the characteristics of simplicity, convenience, convenient operation and reliable data. The method for loading the antifreeze of the present invention can effectively prevent the coal from freezing with the carriage and improve the transportation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a state diagram after unloading the frozen pulverized coal of the test schemes of different embodiments of the present invention.

[0046] Figure 2 It is a distribution diagram of the embedding positions of the temperature sensor probes of the present invention.

[0047] Figure 3 It is a temperature change diagram in the pulverized coal box during the cooling process of Example 1 and Example 2.

[0048] Figure 4 It is a temperature change diagram in the pulverized coal box during the cooling process of Example 3 and Example 4.

[0049] Figure 5 It is a temperature change diagram in the pulverized coal box during the cooling process of Example 5. DETAILED DESCRIPTION OF THE INVENTION

[0050] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the accompanying drawings. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0051] The water-reducing antifreeze for railway coal gondola transportation of the present invention comprises the following raw materials in mass percentages: 30-40% of stearic acid, 30-40% of ethylene glycol, 5% of calcium chloride, 5-10% of polycarboxylic acid, 1-2% of additive, and the balance is deionized water.

[0052] The water-reducing antifreeze for railway coal gondola transportation of the present invention comprises the following raw materials in mass percentages: 40% of stearic acid, 40% of ethylene glycol, 5% of calcium chloride, 10% of polycarboxylic acid, 1% of additive, and the balance is deionized water.

[0053] The additive includes malonic acid, corrosion and scale inhibition concentrate and triethanolamine, and by mass percentage, malonic acid: corrosion and scale inhibition concentrate: triethanolamine = 1:1:1.

[0054] The preparation method of the water-reducing antifreeze for railway coal gondola transportation of the present invention comprises the following steps:

[0055] a. Solution preparation: Add calcium chloride, malonic acid, corrosion inhibitor and triethanolamine to deionized water to prepare a standby solution;

[0056] b. Raw material preparation: Mix stearic acid and ethylene glycol, heat to 50-60°C on a sand bath, and keep warm until the solid is dissolved to prepare the main material;

[0057] c. Adding auxiliary materials: Add polycarboxylic acid to the main material, stir thoroughly for about 1 hour, and wait until the temperature drops to room temperature to form the main mixture;

[0058] d. Mixing process: Pour the prepared standby solution into the main mixture and stir it thoroughly for about 2 hours. When the temperature drops to room temperature, the water-reducing antifreeze product is obtained. Because heat will be released during the mixing process of the standby solution and the main mixture, it needs to be cooled to room temperature again.

[0059] The method for loading a water-reducing antifreeze agent for railway open-top coal transportation of the present invention comprises the following steps:

[0060] S1. Check equipment integrity;

[0061] S2. Apply water-reducing antifreeze agent to the bottom and sides of the open car;

[0062] S3. The coal powder is loaded in the open car using the three-step method: antifreeze is applied to the bottom and sides of the car, and a layer of antifreeze is sprayed on each layer of coal; a layer of antifreeze is also sprayed on the top of the outermost layer;

[0063] S4. According to the depth to be measured, insert the temperature sensor to ensure good contact between the temperature sensor and the medium to obtain accurate temperature data; the temperature sensor has multiple, multiple temperature sensors are evenly distributed in the coal powder inside the open car, and multiple temperature sensors are inserted into three different depths of the coal powder;

[0064] S5. Connect the temperature sensor to the data acquisition controller and turn on the power;

[0065] S6. Check the coal seam temperature data in real time through the display screen of the data acquisition controller. The user can set the required alarm threshold to ensure that the system can issue an alarm in time when the temperature is abnormal;

[0066] S7. After the measurement is completed, pull out the temperature sensor to avoid damage to the coal seam;

[0067] S8. Unload the coal from the open car and weigh and record the mass of the unloaded coal;

[0068] S9. Data recording: record the measured temperature data for subsequent analysis and reference.

[0069] The following several embodiments are used to verify the optimal ratio and the optimal loading method of the water-reducing and anti-freezing agent for railway coal gondola transportation of the present invention.

[0070] Embodiment 1

[0071] The anti-freezing agent of this embodiment comprises raw materials in the following mass percentages: 58% of ethylene glycol and 41% of deionized water.

[0072] The loading method is to spray the anti-freezing agent on the surface layer of the pulverized coal in the gondola car body. The picture after unloading is shown in Figure 1 a.

[0073] Embodiment 2

[0074] The anti-freezing agent of this embodiment comprises raw materials in the following mass percentages: 58% of ethylene glycol and 41% of deionized water.

[0075] The loading method is to spray the anti-freezing agent in layers in the pulverized coal in the gondola car body by the three-division method. The picture after unloading is shown in Figure 1 b.

[0076] Embodiment 3

[0077] The anti-freezing agent of this embodiment comprises raw materials in the following mass percentages: 30% of stearic acid, 40% of ethanol, 5% of calcium chloride, 5% of polycarboxylic acid, 1% of additive, and the rest is deionized water.

[0078] The appearance of the anti-freezing agent is a milky white liquid, the pH is 7.0 - 9.0, the dilution ratio is 3 - 6 times, and the painted area after dilution is 30 - 50 m 2 / kg.

[0079] The loading method is to apply the anti-freezing agent on the bottom and side surfaces inside the gondola car body and spray the anti-freezing agent in layers in the pulverized coal in the car body by the three-division method. The picture after unloading is shown in Figure 1 c.

[0080] Embodiment 4

[0081] The anti-freezing agent of this embodiment comprises raw materials in the following mass percentages: 30% of stearic acid, 40% of ethanol, 5% of calcium chloride, 10% of polycarboxylic acid, 1% of additive, and the rest is deionized water.

[0082] The appearance of the anti-freezing agent is a milky white liquid, the pH is 7.0 - 9.0, the dilution ratio is 3 - 6 times, and the painted area after dilution is 30 - 50 m 2 / kg.

[0083] The loading method is to apply the anti-freezing agent on the bottom and side surfaces inside the gondola car body and spray the anti-freezing agent in layers in the pulverized coal in the car body by the three-division method. The picture after unloading is shown in Figure 1 d.

[0084] Embodiment 5

[0085] The antifreeze of this embodiment comprises raw materials in the following mass percentages: 40% stearic acid, 40% ethanol, 5% calcium chloride, 10% polycarboxylic acid, 1% additive, and the balance being deionized water.

[0086] The appearance of the antifreeze is a milky white liquid, with a pH of 7.0 - 9.0, a dilution ratio of 3 - 6 times, and the painted area after dilution is 30 - 50 m 2 / kg.

[0087] The loading method is to apply the antifreeze to the bottom and sides inside the open wagon body and to spray the antifreeze in layers in the pulverized coal in the wagon body using the three - division method. The pictures after unloading are shown in Figure 1 e.

[0088] Example 6

[0089] The antifreeze of this embodiment comprises raw materials in the following mass percentages: 40% stearic acid, 40% ethanol, 5% calcium chloride, 10% polycarboxylic acid, 1% additive, and the balance being deionized water.

[0090] The appearance of the antifreeze is a milky white liquid, with a pH of 7.0 - 9.0, a dilution ratio of 3 - 6 times, and the painted area after dilution is 30 - 50 m 2 / kg.

[0091] The loading method is, on the basis of Example 5, after unloading the wagon, to spray the antifreeze in layers in the pulverized coal in the open wagon again using the three - division method.

[0092] The specific test schemes and results of Examples 1 - 6 are shown in Table 1.

[0093] Table 1 Test Schemes and Results

[0094]

[0095] The antifreeze of the present invention reduces the water content within the contact range between the high - water - content pulverized coal and the inner wall of the open wagon by 5 - 10%, and its anti - freezing temperature reaches - 35°C. Therefore, it has efficient water - reducing and anti - freezing performance, and at the same time meets the characteristics of easy spraying, low cost, and high stability, meeting the requirements of the negative - temperature transportation environment of high - water - content pulverized coal in the cold season and efficient unloading. At the same time, in order to further reduce costs, a test of secondary loading and unloading on the basis of one - time coating and spraying was also carried out (Example 6), that is, after unloading in Example 5, directly loading the pulverized coal for the second time, and after carrying out the low - temperature transportation test, the secondary unloading rate still remains at a high level.

[0096] As can be seen from the result comparison in Table 1, after adding stearic acid and polycarboxylic acid to the antifreeze, the unloading rate has been significantly improved. In addition, the effect of spraying the antifreeze in layers is also significantly better than that of only spraying the antifreeze on the surface layer of the box body. This is because adding the antifreeze in layers can ensure that the pulverized coal inside the entire carriage is evenly covered by the antifreeze, avoiding local overcooling or freezing due to uneven distribution of the antifreeze. Especially in the case of liquid flow, temperature change or complex use environment, the uniform coverage of the antifreeze on the entire surface helps the entire system maintain stable low-temperature protection.

[0097] Only applying the antifreeze on the inner wall and bottom may cause the liquid to be easily stirred or flow during operation, and the temperature in areas such as the top or middle is still relatively low, resulting in freezing and ineffective antifreeze protection. The top and middle may be prone to icing or other freeze cracking problems due to lack of protection by the antifreeze.

[0098] In addition, adding in layers can also make the antifreeze fully contact with all parts of the object to be protected, better play its roles of water reduction, antifreeze, anti-corrosion and scale inhibition, etc., thereby improving the overall protection effect.

[0099] The arrangement positions of the temperature sensors are as Figure 2 shown. The carriage is separated by a partition in the middle, and two parallel sets of experimental cases for coal anti-freezing can be carried out simultaneously. Among them, temperature sensors No. 15 and 16 are arranged at the bottom of the coal layer in the carriage; temperature sensors No. 17 and 18 are arranged in the middle of the coal layer in the carriage; temperature sensors No. 19 and 20 are arranged at the top of the coal layer in the carriage during the test.

[0100] Figure 3 and Figure 4 are the time-course curves of temperature measurement of temperature sensors No. 15, 16, 17, 18, 19 and 20 during the test, that is, the change process of the temperature at different positions of the coal layer in the carriage over time during the test. Figure 3 In Figure 4 temperature sensors No. 15, 17 and 19 are used to test Example 1, and temperature sensors No. 16, 18 and 20 are used to synchronously test Example 2. In

[0101] Figure 5 temperature sensors No. 15, 17 and 19 are used to test Example 3, and temperature sensors No. 16, 18 and 20 are used to synchronously test Example 4. It is not difficult to find from the experimental test results that from right to left in time, the coal in the whole process of the 4 examples shows an ambient temperature of about -15°C. Figure 5For the test example 5 of temperature sensors No. 1, 3, and 5, and the test example 6 of temperature sensors No. 2, 4, and 6, it is not difficult to find from the experimental test results that from right to left in terms of time, the coal in the whole process of the two examples shows an ambient temperature of around -15°C.

[0102] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0103] Although the above embodiments have been shown and described, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions, and variations made by those of ordinary skill in the art to the above embodiments are within the protection scope of the present invention.

Claims

1. A water reducing antifreeze agent for railway open car transportation of coal, characterized in that: The invention comprises the following raw materials in percentage by weight: 30-40% of stearic acid, 30-40% of ethylene glycol, 5% of calcium chloride, 5-10% of polycarboxylic acid, 1-2% of additives, and the rest of deionized water.

2. The water-reducing and antifreezing agent for railway open-top coal transportation according to claim 1, characterized in that: The invention comprises the following raw materials in percentage by weight: 40% of stearic acid, 40% of ethylene glycol, 5% of calcium chloride, 10% of polycarboxylic acid, 1% of additives, and the rest of deionized water.

3. The water-reducing and antifreezing agent for railway open-top coal transportation according to claim 1, characterized in that: The additives include malonic acid, corrosion and scale inhibitor and triethanolamine, and calculated by mass percentage, malonic acid: corrosion and scale inhibitor: triethanolamine=1:1:

1.

4. A method for preparing a water-reducing antifreeze agent for railway open-top coal transportation according to any one of claims 1 to 3, characterized in that: The following steps are involved: a. Solution preparation: Add calcium chloride and additives to deionized water to prepare a standby solution; b. Raw material preparation: Stearic acid and ethylene glycol are mixed, heated on a sand bath, and kept warm until the solid is dissolved to prepare the main material; c. Adding auxiliary materials: Add polycarboxylic acid to the main material and stir until the temperature drops to room temperature to form the main mixture; d. Mixing process: Pour the prepared solution in step a into the main mixture and stir evenly to obtain the finished product of water-reducing antifreeze.

5. The method for preparing a water-reducing antifreeze agent for railway open-top coal transportation according to claim 4, characterized in that: The temperature of the sand bath is 50-60°C.

6. A method for loading a railway open car coal transport water reducing antifreeze agent according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1. Check equipment integrity; S2. Apply water-reducing antifreeze agent to the bottom and sides of the open car; S3. The three-step method is used to load coal powder in the open car, and each layer of coal is sprayed with a layer of antifreeze; S4. Insert the temperature sensor according to the depth to be measured, and ensure that the temperature sensor is in good contact with the medium to obtain accurate temperature data; S5. Connect the temperature sensor to the data acquisition controller and turn on the power; S6. Check the coal seam temperature data in real time through the display screen of the data acquisition controller. The user can set the required alarm threshold to ensure that the system can issue an alarm in time when the temperature is abnormal; S7. After the measurement is completed, pull out the temperature sensor to avoid damage to the coal seam; S8. Unload the coal from the open car and weigh and record the mass of the unloaded coal; S9. Data recording: record the measured temperature data for subsequent analysis and reference.

7. The method for loading water-reducing antifreeze agent for railway open car transportation of coal according to claim 6, characterized in that: A layer of antifreeze is also sprayed on the top of the outermost layer of the coal powder in the three-part method.

8. The method for loading water-reducing antifreeze agent for railway open car transportation of coal according to claim 6, characterized in that: There are multiple temperature sensors, which are evenly distributed in the coal powder inside the open wagon, and are respectively inserted into three different depths of the coal powder.

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