Anti-freezing solution for transportation and storage of solid particles as well as preparation method and application of anti-freezing solution

Abstract

The invention discloses an anti-freezing solution for transportation and storage of solid particles as well as a preparation method and application of the anti-freezing solution, and belongs to the technical field of anti-freezing solutions for railway transportation. The raw materials comprise the following components in parts by weight: 660-1006 parts of calcium chloride; and 1312 to 2000 parts of water. 10 to 15.2 parts of borax; 6 to 9 parts of triethanolamine; 10 to 15 parts of sodium nitrite; and 2-3 parts of hydroxyethyl cellulose. According to the anti-freezing solution disclosed by the invention, the strict requirements of transportation or storage of solid particulate matters under extremely cold conditions on efficient, anti-corrosion, safe and environment-friendly anti-freezing solutions are met by utilizing the synergistic effect of all the components.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of railway transportation antifreeze, in particular to an antifreeze for solid particle transportation and storage, and a preparation method and application thereof. BACKGROUND

[0002] Inorganic salt antifreeze: sodium chloride, calcium chloride and other single inorganic salts are used as main components to achieve antifreeze effect by reducing the freezing point of the aqueous solution. Although this kind of inorganic salt antifreeze has low cost, it has strong corrosiveness to the metal materials of railway freight carriages (such as carbon steel and stainless steel), which can cause thinning and perforation of the carriage wall, shorten the service life of the carriage, and increase the maintenance cost. High concentration of chloride ions in inorganic salt antifreeze can cause pitting corrosion of the metal carriage. The average floor of the carriage using single calcium chloride antifreeze needs to be replaced every 2 years, and the maintenance cost increases by 300 yuan per carriage. The inorganic salt antifreeze has limitations in antifreeze performance: the freezing point adjustment range of single inorganic salt is limited, and the antifreeze effect is poor in extremely cold areas (below -30℃). Below -30℃, inorganic salt antifreeze is easy to crystallize and lose effectiveness. For example, single calcium chloride aqueous solution will form crystalline hydrate below -55℃, causing freezing of goods and carriage, and reducing the unloading efficiency by more than 50%. Inorganic salt antifreeze has great safety and environmental protection risks: inorganic salt antifreeze can cause land salinization and affect the vegetation along the line.

[0003] Alcohol antifreeze: common alcohol aqueous solutions include ethylene glycol and propylene glycol. This kind of antifreeze has good low-temperature fluidity and antifreeze performance, but has great safety and environmental protection risks: it is flammable and volatile, and once leaked in railway transportation and loading and unloading operations, it can easily cause fire and be adsorbed by bulk goods such as grain, affecting the quality. In addition, alcohol substances can undergo oxidation reaction in the long-term use process, generating acidic substances, which can cause corrosion and swelling of metal and rubber parts. Alcohol antifreeze has limitations in antifreeze performance, for example, the viscosity of ethylene glycol-water system reaches 80 mPa·s at -40℃, affecting the use effect. In addition, alcohol substances have high viscosity, poor stability and adaptability, and cannot be atomized by railway special spraying equipment.

[0004] Composite antifreeze: Some existing technologies attempt to combine inorganic salts with organic additives, which improves performance to some extent. However, unreasonable selection of additives in the formula leads to unstable antifreeze viscosity, making it prone to stratification and crystallization at low temperatures, affecting spray uniformity and antifreeze effect. Furthermore, it may have adverse effects on bulk cargo, such as altering the physicochemical properties of particulate cargo and affecting cargo quality. Composite antifreeze is highly corrosive: Under alternating loads on railway freight cars, the protective film on metal surfaces is easily ruptured by the single corrosion inhibitor in composite antifreeze. After vibration testing, the corrosion rate of carbon steel increased sharply from 0.05 mm / a to 0.21 mm / a. Some composite antifreeze exhibits "salting out" at low temperatures, clogging spray equipment filters and increasing maintenance costs. In addition, composite antifreeze is prone to stratification under railway transport vibration, exhibiting poor stability and compatibility; after 200 km of operation, the calcium chloride concentration difference between the upper and lower layers of the antifreeze reaches 15%.

[0005] In summary, inorganic salt-based antifreeze has several drawbacks: poor antifreeze performance in extremely cold conditions, easy crystallization, strong corrosiveness that can damage carriages, and soil pollution that impacts vegetation. Alcohol-based antifreeze poses a fire hazard due to its flammability, affects cargo quality, and can cause rubber parts to swell, leading to brake failure. Composite antifreeze is prone to precipitation and equipment blockage at low temperatures, its protective film is easily damaged, and it produces uneven spraying. Other antifreeze types, such as glycerol-based antifreeze, suffer from high viscosity and difficulty in atomization, while ester-based antifreeze is costly and difficult to degrade. Therefore, existing technologies in the field of antifreeze for bulk railway freight transport suffer from insufficient antifreeze performance, strong corrosiveness, poor safety, and poor stability, failing to meet the railway transportation industry's demand for efficient, safe, and environmentally friendly antifreeze. Summary of the Invention

[0006] According to one embodiment of the present invention, the object is to provide an antifreeze for transporting and storing solid particulate matter, a method for preparing the same, and its application, so as to meet the needs of transporting and storing solid particulate matter under extremely cold conditions.

[0007] The above objective can be achieved through the following technical solutions: According to one aspect of the present invention, an antifreeze for transporting and storing solid particulate matter is provided, comprising, by weight, the following raw materials: 660-1006 parts calcium chloride; 1312-2000 parts water; 10-15 parts borax; 6-9 parts triethanolamine; 10-15 parts sodium nitrite; and 2-3 parts hydroxyethyl cellulose.

[0008] Preferably, the raw materials further include 174-265 parts by weight of potassium carbonate.

[0009] Preferably, the raw materials also include 20-30 parts by weight of sodium tripolyphosphate.

[0010] Preferably, the raw materials also include 2-3 parts by weight of calcium lignosulfonate.

[0011] Preferably, the particle size of calcium chloride is <5mm.

[0012] Preferably, the borax is passed through an 80-mesh sieve.

[0013] Preferably, the hydroxyethyl cellulose has a viscosity of 20,000-30,000 mPa·s and passes through a 100-mesh sieve.

[0014] Preferably, the viscosity of the antifreeze is 10-20 mPa·s.

[0015] Preferably, the pH of the antifreeze is 9-10.

[0016] Preferably, the freezing point of the antifreeze is -41°C to -43°C.

[0017] According to another aspect of the present invention, a method for preparing an antifreeze for transporting and storing solid particulate matter is provided, comprising: Add water to the stainless steel reactor, turn on the stirrer at a speed of 100-140 r / min to create a vortex in the water; and turn on the circulating cooling water in the reactor jacket to control the reaction temperature at 25-30℃. Add the following components to the reactor in the following order: calcium chloride, borax, triethanolamine, sodium nitrite, hydroxyethyl cellulose, potassium carbonate, sodium tripolyphosphate, and calcium lignosulfonate. Stir continuously for 6-10 minutes after each component is added. When adding hydroxyethyl cellulose, sprinkle it evenly on the surface of the solution using a powdering method. After all components have been added, increase the stirring speed to 200-240 r / min and continue stirring for 30-40 minutes to obtain the antifreeze.

[0018] Preferably, the preparation method further includes: online real-time monitoring of solution viscosity, and ensuring that the viscosity of the antifreeze is between 10 and 20 mPa·s by fine-tuning the amount of hydroxyethyl cellulose added.

[0019] Preferably, the preparation method further includes: letting the antifreeze stand for 1.2-1.8 hours and observing whether there is stratification and / or precipitation; if stratification and / or precipitation occurs, stirring at a speed of 140-160 r / min for 18-22 minutes; or, filtering the antifreeze through a 200-mesh filter.

[0020] According to another aspect of the present invention, an antifreeze for transporting and storing solid particles is provided for transporting or storing solid particles under extremely cold conditions, wherein the temperature of the extremely cold weather is below -30°C.

[0021] According to one embodiment of the present invention, by designing and optimizing the proportions of functional components, the synergistic effect between the components is utilized to improve the antifreeze performance, enhance corrosion resistance, ensure safety and environmental protection, and improve stability and compatibility of the antifreeze. Specifically, calcium chloride lowers the freezing point, and the ionic environment generated by its ionization helps the corrosion-resistant system (i.e., borax, triethanolamine, and sodium nitrite) constructed in this invention to form a more stable protective film on the metal surface of transport / storage equipment. Borax and triethanolamine adjust the pH value, providing suitable alkaline conditions for sodium nitrite to form a passivation film, thus enhancing the corrosion resistance. The three-dimensional network structure of hydroxyethyl cellulose not only stabilizes the physical state of the antifreeze but also assists the corrosion-resistant components in uniformly adhering to the metal surface, further improving corrosion resistance. Moreover, when the components of the antifreeze of this invention are mixed in the aforementioned proportions, the overall performance of the antifreeze reaches its optimal level, with its antifreeze, corrosion resistance, and stability indicators improving by more than 30% compared to adding a single component. The synergistic effect of the components in the formula of this invention improves the overall performance and meets the stringent requirements of antifreeze for high efficiency, corrosion prevention, safety and environmental protection in the transportation or storage of solid particulate matter under extremely cold conditions.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1) Improved antifreeze performance: By optimizing the ratio of calcium chloride content to hydroxyethyl cellulose, the antifreeze has a freezing point of -41℃ to -43℃. At this extremely low temperature, it still maintains a suitable viscosity (10-20 mPa·s) and does not crystallize for a long time (72-120 hours), maintaining good fluidity. This avoids crystallization and ensures good spray atomization, meeting the needs of solid particulate matter for railway transportation / storage in extremely cold regions.

[0023] 2) Enhanced Corrosion Resistance: By constructing a triple anti-corrosion system of borax, triethanolamine, and sodium nitrite, the corrosion resistance is enhanced. Specifically, the corrosion rate of Q235 carbon steel can be reduced to 0.01 mm / a, significantly lower than the national standard, effectively protecting the metal materials of railway freight cars and extending their service life. Adjusting the pH of the antifreeze to 9-10 using borax and triethanolamine provides suitable alkaline conditions for the formation of a passivation film by sodium nitrite, effectively enhancing the anti-corrosion effect.

[0024] 3) By adding potassium carbonate, the antifreeze properties of the antifreeze can be further enhanced, ensuring that the antifreeze maintains good fluidity and does not crystallize for a longer period of time under the corresponding freezing point temperature environment.

[0025] 4) Ensuring safety and environmental protection: The formula is alcohol-free and the sodium nitrite content is strictly controlled. The residual amount in the goods is far below the national standard. Moreover, the ingredients in the formula are biodegradable and the waste liquid has no inhibitory effect on plant growth, ensuring the safety of transported goods and environmental friendliness.

[0026] 5) Improved stability and compatibility: The three-dimensional network structure formed by hydroxyethyl cellulose maintains uniform dispersion of each component under the vibration conditions of railway transportation, with a concentration difference of <3%; at the same time, the viscosity, surface tension and other parameters of the antifreeze are controlled within a suitable range, making it compatible with existing railway freight spraying equipment (achieving good atomization effect), reducing the equipment failure rate by 75% (equipment failure rate <0.5%), and saving maintenance costs. Detailed Implementation

[0027] The technical solution of the present invention will be clearly and completely described below with reference to embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0028] Based on the multiple requirements of railway bulk freight in extremely cold environments for cargo antifreeze, equipment corrosion prevention, environmental safety, and equipment compatibility, this invention constructs a multi-performance synergistic antifreeze formula by selecting and optimizing functional components such as antifreeze, corrosion prevention, and stabilization. By utilizing the synergistic effect between the components, it solves the problems of existing antifreeze performance failure, severe metal corrosion, poor stability, and safety and environmental hazards under extremely cold conditions, thus meeting the stringent requirements of the railway solid particulate matter transportation industry in extremely cold environments.

[0029] This invention provides an antifreeze for transporting and storing solid particulate matter. By weight, the raw materials include: 660-1006 parts calcium chloride; 1312-2000 parts water; 10-15 parts borax; 6-9 parts triethanolamine; 10-15 parts sodium nitrite; and 2-3 parts hydroxyethyl cellulose. The components in this formulation achieve performance enhancement through synergistic effects. The raw materials are proportioned according to the above weight percentages, resulting in optimal overall performance of the antifreeze. Its antifreeze, anticorrosive, and stability indicators are improved by approximately 40%, 55%, and 35%, respectively, compared to the addition of a single component.

[0030] The functions and working principles of the antifreeze, anticorrosion, and stabilizing components of this invention are explained below: The core component of the antifreeze is calcium chloride. Its working principle is based on the colligative property of dilute solutions. When calcium chloride dissolves in water, it ionizes into calcium ions and chloride ions. These ions are uniformly dispersed between water molecules, hindering the orderly arrangement of water molecules to form ice crystals, thereby lowering the freezing point of the aqueous solution. Furthermore, it provides a more favorable ionic environment for the formation of a protective film in the corrosion protection system. The inventors have verified through extensive experimental data that when the calcium chloride content in the antifreeze of this invention is within the above-mentioned range, the freezing point of the antifreeze can be effectively lowered to below -40°C, which is more conducive to the formation of a more stable protective film on the metal surface by the corrosion protection system.

[0031] The anti-corrosion component system is composed of borax, triethanolamine, and sodium nitrite in a specific ratio.

[0032] Borax hydrolyzes in aqueous solution to generate boric acid and hydroxide ions, acting as a pH buffer. Through research and testing, the inventors discovered that when the borax content in the antifreeze of this invention is within the aforementioned range, the pH value of the antifreeze can be stably adjusted to a weakly alkaline range of 9-10. Under this alkaline environment, the antifreeze exhibits a significant inhibitory effect on metal corrosion. In accelerated corrosion experiments simulating railway transportation environments, compared to a control group without added borax, the antifreeze of this invention reduced the corrosion rate of carbon steel by approximately 65%. Furthermore, the borate ions generated from borax hydrolysis can react with metal ions on the metal surface to form a dense borate protective film, isolating the corrosive medium from contact with the metal, thereby enhancing corrosion resistance.

[0033] Triethanolamine acts as a pH adjuster, working synergistically with borax to maintain the alkaline environment of the antifreeze. Furthermore, the amino and hydroxyl groups in its molecular structure can complex with metal ions, forming stable complexes on the metal surface and thus blocking the electrochemical corrosion pathway. In corrosion tests on stainless steel, after adding the specified amount of triethanolamine to the antifreeze, the corrosion current density decreased from 0.5 μA / cm². 2 Reduced to 0.1 μA / cm 2 It effectively prevents metal oxidation and provides good corrosion inhibition for carbon steel, stainless steel and other metal materials commonly used in railway freight cars.

[0034] Sodium nitrite, as a highly efficient metal corrosion inhibitor, can undergo a redox reaction with iron on the metal surface under weakly alkaline conditions. X-ray photoelectron spectroscopy (XPS) analysis revealed that when the sodium nitrite content in the antifreeze is within the aforementioned range, the Fe2O3 passivation film formed on the metal surface reaches a thickness of 80-100 nm, exhibiting excellent chemical stability and barrier properties, effectively preventing contact between corrosive substances such as oxygen and moisture and the metal. Furthermore, in a 120-day salt spray test, the metal sample using this antifreeze showed only slight rust spots, while the control sample (without sodium nitrite) showed extensive corrosion, significantly enhancing the antifreeze's corrosion protection capability for metal components.

[0035] Stabilizing and thickening component: Hydroxyethyl cellulose is a water-soluble polymer compound. In aqueous solution, its molecular chains interact through hydrogen bonds and van der Waals forces to form a three-dimensional network structure. Through extensive experiments, the inventors discovered that when the hydroxyethyl cellulose content in the antifreeze is within the aforementioned range, the antifreeze viscosity can be adjusted to 10-20 mPa·s. At a low temperature of -25℃, the antifreeze without added hydroxyethyl cellulose exhibits obvious stratification, while the antifreeze with added hydroxyethyl cellulose remains uniform and stable. The appropriate viscosity also ensures good atomization of the antifreeze in railway-specific spraying equipment (working pressure 3-5 MPa). High-speed camera observation shows that the atomized particle size is all <100 μm, ensuring that the antifreeze can be evenly sprayed onto the surface of bulk cargo and carriages, thus achieving optimal antifreeze and anti-corrosion effects.

[0036] In some preferred embodiments, the raw materials further include, by weight, 174-265 parts of potassium carbonate. Preferably, 210-240 parts of potassium carbonate. By adding potassium carbonate, the antifreeze properties of the antifreeze can be further enhanced, ensuring that it maintains good fluidity and remains free of crystallization for a longer period of time under the stated freezing point environment.

[0037] In some embodiments, the raw materials further include 20-30 parts by weight of sodium tripolyphosphate. Adding sodium tripolyphosphate within this range effectively prevents crystallization of highly concentrated calcium chloride solution from affecting the freezing point.

[0038] In some embodiments, the raw materials further include 2-3 parts by weight of calcium lignosulfonate. By adding calcium lignosulfonate within the range described above, and synergistically with hydroxyethyl cellulose, the flowability of the antifreeze in extremely cold environments can be improved more effectively.

[0039] This invention also provides a method for preparing the antifreeze, which is prepared according to the following steps.

[0040] (1) Add deionized water to a stainless steel reactor of suitable volume (e.g., 500L), turn on the stirring device, and set the stirring speed to 100-140r / min to make the water form a stable vortex.

[0041] In this process, the circulating cooling water in the jacket of the reactor is turned on to control the reaction temperature at 25-30℃, preventing the temperature from becoming too high due to heat generated by stirring and friction, which would affect the performance of each component.

[0042] (2) Add calcium chloride, borax, triethanolamine, sodium nitrite, hydroxyethyl cellulose, potassium carbonate, sodium tripolyphosphate and calcium lignosulfonate into the reaction vessel in that order and stir.

[0043] After each component is added, stir continuously for 6-10 minutes to ensure full dissolution and dispersion, and to avoid uneven reaction caused by excessively high local concentrations.

[0044] When adding hydroxyethyl cellulose, use a dusting method to evenly sprinkle it on the surface of the solution to prevent clumping.

[0045] (3) After all components have been added, increase the stirring speed to 200-240 r / min and continue stirring for 30-40 minutes to make the solution evenly mixed and form a uniform and stable antifreeze.

[0046] The viscosity range of the antifreeze of this invention is 10-20 mPa·s. During the preparation process, a rotational viscometer can be used to monitor the solution viscosity (at room temperature) online in real time. By fine-tuning the amount of hydroxyethyl cellulose added, the viscosity of the antifreeze can be ensured to be within the target range, ensuring the antifreeze is uniform and stable, preventing stratification, and ensuring the atomization effect during subsequent use, thereby fully exerting the optimal antifreeze and anticorrosion effects of the antifreeze.

[0047] The antifreeze of this invention has a freezing point of -41°C to -43°C. During the preparation process, the freezing point of the antifreeze can be detected using a freezing point meter, and the amount of calcium chloride or potassium carbonate can be adjusted appropriately to ensure that it falls within this range.

[0048] The antifreeze of this invention has a pH of 9-10. During the preparation process, a portable pH meter can be used to detect the pH value of the antifreeze, and the amounts of borax and triethanolamine can be adjusted appropriately to ensure that it is within the specified range.

[0049] To further ensure the uniformity and stability of the antifreeze and avoid sedimentation, let the antifreeze stand for 1.2-1.8 hours and observe whether there is stratification and / or sedimentation. If stratification and / or sedimentation occur, stir at 140-160 r / min for 18-22 minutes; or, filter the antifreeze through a 200-mesh filter.

[0050] In addition, to further improve the performance of the antifreeze, the raw materials are pretreated as follows: Calcium chloride: Before use, test its chloride ion content, heavy metal content, and other indicators to ensure compliance with GB / T 26520-2011 standard. Crush lumpy calcium chloride to a particle size of <5mm for easy dissolution.

[0051] Borax: Pharmaceutical grade borax (Na2B4O7・10H2O, purity ≥99%) is used. Before use, it is passed through an 80-mesh sieve to remove impurities and agglomerated particles.

[0052] Triethanolamine: Select analytical grade triethanolamine (purity ≥ 99.5%). Before use, test its density (it should be 1.122 - 1.130 g / cm³ at 25℃). 3 Indicators such as pH value (10.5 - 11.5).

[0053] Sodium nitrite: Industrial sodium nitrite (purity ≥98%) is used. Its nitrite content, moisture content and other indicators need to be tested to ensure compliance with GB 2367-2006 standard.

[0054] Hydroxyethyl cellulose: Food-grade hydroxyethyl cellulose (viscosity 20000 - 30000 mPa·s) should be selected. Before use, the moisture content (≤5%) should be tested and the cellulose should be passed through a 100-mesh sieve.

[0055] Water: Deionized water with conductivity ≤5μS / cm and pH value 6.5-7.5 is used. Its hardness (≤50mg / L as CaCO3) must be tested before use.

[0056] This invention's antifreeze has a very low freezing point and excellent low-temperature performance, making it suitable for the transportation / storage of solid particles in environments below -30°C. In particular, it maintains suitable viscosity and atomization even under extremely cold conditions of -41°C and below, and shows no crystallization after 72-120 hours of transportation / storage at this temperature. It exhibits strong corrosion resistance, significantly reducing the corrosion rate of carbon steel, and no corrosion occurred in metal cargo compartments after prolonged use. It demonstrates good stability, with uniform composition even under vibration, no stratification during use, and excellent atomization and uniform spraying. Furthermore, it is safe and environmentally friendly, being alcohol-free and friendly to both goods and the environment. It also boasts high compatibility, adapting to existing equipment and reducing the failure rate.

[0057] The implementation methods and effects of the present invention will be described below with reference to specific embodiments: Example 1 1) Weigh the raw materials Calcium chloride 700g; deionized water 1921g; borax 14.6g; triethanolamine 8.8g; sodium nitrite 14.6g; hydroxyethyl cellulose 2.9g.

[0058] 2) Preparation Add deionized water to the stainless steel reactor, turn on the agitator, and set the stirring speed to 120 r / min to create a stable vortex in the water. Simultaneously, turn on the circulating cooling water in the reactor jacket to control the reaction temperature at 25-30℃, preventing excessively high temperatures caused by friction during stirring, which could affect the properties of the components.

[0059] Calcium chloride, borax, triethanolamine, sodium nitrite, and hydroxyethyl cellulose were added to the reaction vessel in that order, slowly and continuously. After each component was added, the mixture was stirred for 8 minutes to ensure complete dissolution and dispersion, and to avoid uneven reaction caused by excessively high local concentrations. When adding hydroxyethyl cellulose, the "powdering method" was used to evenly sprinkle it on the surface of the solution to prevent clumping.

[0060] After all components have been added, increase the stirring speed to 220 rpm and continue stirring for 35 minutes to ensure the solution is thoroughly mixed and forms a homogeneous and stable antifreeze. Stop stirring and allow the prepared antifreeze to stand for 1.5 hours, observing for any stratification or precipitation.

[0061] 3) Packaging The product is packaged in plastic drums, each with a capacity of 25kg. Before packaging, the drums must be cleaned and dried, and the product name, formula number, production date, shelf life, and other information must be marked on the drum.

[0062] Test results: The antifreeze has a pH of 9.5, a viscosity of 16 mPa·s at 25°C, and a freezing point of -41°C.

[0063] The prepared antifreeze was tested by the National Railway Product Quality Supervision and Inspection Center: It maintains good fluidity at -41℃ and does not crystallize after 95 hours at the corresponding low temperature, meeting the needs of railway transportation in extremely cold regions and exhibiting excellent antifreeze properties.

[0064] The corrosion rate on Q235 carbon steel is as low as 0.01 mm / a, which is significantly lower than the national standard requirement (0.05 mm / a). In a 120-day salt spray test, the metal specimens using the antifreeze of this invention only showed slight rust spots, indicating good metal corrosion resistance.

[0065] After a simulated vibration test on a railway (amplitude 8 mm, frequency 30 Hz, duration 4 hours), the concentration difference of each component was <3%, indicating excellent stability.

[0066] Furthermore, the antifreeze is alcohol-free, low in toxicity, and biodegradable, ensuring the safety of transported goods and the environment.

[0067] Example 2 The difference from Example 1 is that 1) the raw materials also include: 232g of potassium carbonate.

[0068] Test results: The antifreeze has a pH of 9.6, a viscosity of 16 mPa·s at 25°C, and a freezing point of -43°C.

[0069] The prepared antifreeze was tested by the National Railway Product Quality Supervision and Inspection Center: It maintains good fluidity at -43℃ and does not crystallize after 118 hours at the corresponding low temperature, meeting the needs of railway transportation in extremely cold regions and exhibiting excellent antifreeze properties.

[0070] The corrosion rate on Q235 carbon steel is as low as 0.009 mm / a, which is significantly lower than the national standard requirement. Metal test pieces using the antifreeze of this invention showed only slight rust spots in a 120-day salt spray test.

[0071] After a simulated vibration test on a railway (amplitude 8 mm, frequency 30 Hz, duration 4 hours), the concentration difference of each component was <2.8%, indicating excellent stability.

[0072] Furthermore, the antifreeze is alcohol-free, low in toxicity, and biodegradable, ensuring the safety of transported goods and the environment.

[0073] Example 3 The difference from Example 1 is that 1) the raw materials also include: 232g of potassium carbonate; 29g of sodium tripolyphosphate; and 2.9g of calcium lignosulfonate.

[0074] Test results: The antifreeze has a pH of 9.6, a viscosity of 14 mPa·s at 25°C, and a freezing point of -43°C.

[0075] The prepared antifreeze was tested by the National Railway Product Quality Supervision and Inspection Center: It maintains good fluidity at -43℃ and does not crystallize after 120 hours at the corresponding low temperature, meeting the needs of railway transportation in extremely cold regions and exhibiting excellent antifreeze properties.

[0076] The corrosion rate on Q235 carbon steel is as low as 0.008 mm / a, which is significantly lower than the national standard requirement; in a 120-day salt spray test, the metal test pieces using the antifreeze of this invention only showed slight rust spots.

[0077] After a simulated vibration test on a railway (amplitude 8 mm, frequency 30 Hz, duration 4 hours), the concentration difference of each component was <2.5%, indicating excellent stability.

[0078] Furthermore, the antifreeze is alcohol-free, low in toxicity, and biodegradable, ensuring the safety of transported goods and the environment.

[0079] Comparative Example 1 The difference from Example 1 is that the anti-corrosion component system does not contain borax.

[0080] Test results: The pH value of the antifreeze was below 9. In an accelerated corrosion test simulating a railway transportation environment, the corrosion rate of this comparative example against Q235 carbon steel was 0.15 mm / a.

[0081] Comparative Example 2 The difference from Example 1 is that the preservative component system does not contain triethanolamine.

[0082] Testing: The antifreeze had a pH value below 9, and in the corrosion resistance test on stainless steel, the corrosion current density was 0.7 μA / cm². 2 .

[0083] Comparative Example 3 The difference from Example 1 is that the preservative component system does not contain sodium nitrite.

[0084] Test results: Metal samples using this antifreeze showed extensive corrosion during a 120-day salt spray test.

[0085] Comparative Example 4 The difference from Example 1 is that the anti-corrosion component system is: 7g borax; 4g triethanolamine; 20g sodium nitrite.

[0086] Test results: The pH value of the antifreeze was below 9, and the corrosion rate of Q235 carbon steel in the 120-day salt spray test was above 0.03 mm / a. The metal test piece using the antifreeze still showed large-area corrosion.

[0087] Comparative Example 5 The difference from Example 1 is that the raw materials do not contain stable components, that is, the raw materials do not contain hydroxyethyl cellulose.

[0088] Test results: At a low temperature of -25℃, the antifreeze without added hydroxyethyl cellulose showed obvious stratification.

[0089] In summary, the antifreeze of this invention exhibits superior antifreeze performance. With the addition of calcium chloride or potassium carbonate in the specified proportions, the antifreeze achieves a freezing point of -41°C to -43°C and remains crystallized for 72-120 hours at these low temperatures, thus solving the problem of cargo freezing in cold regions. The antifreeze of this invention also possesses highly efficient anti-corrosion properties. A triple anti-corrosion system is constructed using borax, triethanolamine, and sodium nitrite in specific proportions. In the examples, the antifreeze showed a corrosion rate of only 0.008-0.012 mm / a on Q235 carbon steel after 120 days of salt spray testing, far below national standards, extending the lifespan of the vehicle compartment. Furthermore, the antifreeze of this invention exhibits excellent stability. By adding hydroxyethyl cellulose in the specified proportions, the viscosity of the antifreeze can be maintained at 10-20 mPa·s, resulting in good atomization. After vibration testing, the component concentration difference is <2.5%, ensuring no stratification at low temperatures and uniform spraying.

[0090] Comparing the embodiments of the present invention with Comparative Example 1, it can be seen that the antifreeze of the present invention can reduce the corrosion rate of carbon steel by about 65% compared with that without the addition of borax.

[0091] Comparing the embodiments of the present invention with Comparative Example 2, it can be seen that the antifreeze of the present invention reduces the corrosion current density from 0.5 μA / cm². 2 Reduced to 0.1 μA / cm 2 This effectively prevents the metal from undergoing oxidation.

[0092] Comparing the embodiments of the present invention with Comparative Example 3, it can be seen that the metal test piece using the antifreeze of the present invention only showed slight rust spots, while the test piece in Comparative Example 3 had extensive corrosion.

[0093] Comparing the embodiments of the present invention with Comparative Example 4, it can be seen that: when the anti-corrosion system is not constructed according to the proportions described in the present invention, the corrosion rate of Q235 carbon steel is high in the 120-day salt spray test, and the corrosion of the metal specimen is more serious.

[0094] Comparing the embodiments of the present invention with Comparative Example 5, it can be seen that the viscosity of the antifreeze of the present invention can be maintained within a specific range, the antifreeze maintains a uniform and stable state, has a good atomization effect, and the atomized particle size is all <100μm.

[0095] Compared with Example 1, Example 2 of the present invention added potassium carbonate. As the test results show, the antifreeze of Example 2 still maintains good fluidity at -43°C (lower temperature than Example 1), and there is no crystallization at this low temperature (for a longer time) for 118 hours. It can be seen that the addition of potassium carbonate further improves the antifreeze properties, making the antifreeze have a lower freezing point and maintain good fluidity (no crystallization) for a longer time.

[0096] The description of this invention is given for illustrative and descriptive purposes only and is not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. An antifreeze for transporting and storing solid particulate matter, characterized in that, By weight, the raw materials include: 660-1006 parts calcium chloride; 1312-2000 parts water; 10-15 parts borax; 6-9 parts triethanolamine; 10-15 parts sodium nitrite; and 2-3 parts hydroxyethyl cellulose.

2. The antifreeze for transporting and storing solid particulate matter according to claim 1, characterized in that, Also includes: Potassium carbonate 174-265 parts.

3. The antifreeze for transporting and storing solid particulate matter according to claim 1, characterized in that, Also includes: 20-30 parts of sodium tripolyphosphate.

4. The antifreeze for transporting and storing solid particulate matter according to claim 1, characterized in that, Also includes: 2-3 parts calcium lignosulfonate.

5. The antifreeze for transporting and storing solid particulate matter according to claim 1, characterized in that, Calcium chloride has a particle size of <5mm; Borax passed through an 80-mesh sieve; Hydroxyethyl cellulose has a viscosity of 20,000 - 30,000 mPa·s and passes through a 100-mesh sieve.

6. The antifreeze for transporting and storing solid particulate matter according to claim 1, characterized in that, The viscosity of the antifreeze is 10-20 mPa·s; The pH of the antifreeze is 9-10; The freezing point of the antifreeze is -41°C to -43°C.

7. A method for preparing an antifreeze for transporting and storing solid particulate matter according to any one of claims 1-6, characterized in that, include: Add water to the stainless steel reactor, turn on the stirrer at a speed of 100-140 r / min to create a vortex in the water; and turn on the circulating cooling water in the reactor jacket to control the reaction temperature at 25-30℃. Add the following components to the reactor in the following order: calcium chloride, borax, triethanolamine, sodium nitrite, hydroxyethyl cellulose, potassium carbonate, sodium tripolyphosphate, and calcium lignosulfonate. Stir continuously for 6-10 minutes after each component is added. When adding hydroxyethyl cellulose, sprinkle it evenly on the surface of the solution using a powdering method. After all components have been added, increase the stirring speed to 200-240 r / min and continue stirring for 30-40 minutes to obtain the antifreeze.

8. The method for preparing antifreeze for transporting and storing solid particulate matter according to claim 7, characterized in that, Also includes: The viscosity of the solution is monitored online in real time, and the amount of hydroxyethyl cellulose added is finely adjusted to ensure that the viscosity of the antifreeze is between 10 and 20 mPa·s.

9. The method for preparing antifreeze for transporting and storing solid particulate matter according to claim 7, characterized in that, Also includes: Let the antifreeze stand for 1.2-1.8 hours and observe whether there is stratification and / or precipitation. If stratification and / or sedimentation occur, stir at 140-160 rpm for 18-22 minutes; or, filter the antifreeze through a 200-mesh filter.

10. The application of an antifreeze for transporting and storing solid particulate matter according to any one of claims 1-6, characterized in that, Used for the transport or storage of solid particulate matter under extremely cold conditions, where the temperature of the extremely cold weather is below -30°C.