A green edible salt production process
By employing a process involving secondary cooling, sieving, iodization, and pre-packaging storage, combined with a powder flow plate cooler and highly airtight packaging, the problem of clumping in green edible salt during production, transportation, storage, and use has been solved. This achieves an anti-caking effect with zero added anti-caking agents, meeting green food standards.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHONGQING SOTE SALT CHEM IND
- Filing Date
- 2024-03-28
- Publication Date
- 2026-06-12
AI Technical Summary
In existing green edible salt production processes, the clumping problem caused by the lack of added anti-caking agents makes it difficult to effectively prevent or delay the clumping of edible salt during production, transportation, storage, and use.
The process involves secondary cooling, sieving, iodization, and storage before packaging. Combined with a powder flow plate cooler and barrier packaging, the temperature and moisture of the salt particles are reduced. Large-diameter salt particles are selected, and pseudo-agglomerates are broken up by mechanical force in the storage silo. Finally, highly airtight packaging is used for packaging.
It effectively prevents or delays the clumping of edible salt without adding anti-caking agents, meets green food standards, and extends the shelf life.
Smart Images
Figure CN122187073A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of edible salt, in particular to a green edible salt production process. BACKGROUND
[0002] Sodium chloride crystals are hygroscopic by nature, which can easily absorb water when the relative humidity is above 75%, and release water when the relative humidity decreases. Although most of the water is removed through different processes during production, a small amount of water remains in the crystal salt particles or between the salt particles due to various influencing factors. During processing, transportation and storage, the evaporation of water in the salt leads to recrystallization and the formation of crystal bridges, which ultimately causes the occurrence of caking.
[0003] In order to prevent or delay the occurrence of caking, the conventional production process uses the addition of anti-caking agents during production. The addition of potassium ferrocyanide / sodium ferrocyanide does not meet the NY / T1040 "Green Food Edible Salt" standard, and the addition of ferric ammonium citrate will affect the whiteness of the salt, both of which have certain drawbacks.
[0004] The caking of edible salt during production, transportation, storage and use is affected by various factors, such as the purity of the crystalline product, particle size, environmental humidity, packaging temperature, etc. To achieve zero addition of anti-caking agents and prevent or delay the caking of edible salt crystals is a key problem that needs to be solved in the current green edible salt production process. SUMMARY
[0005] The present application proposes a green edible salt production process, which solves the problem of caking of edible salt crystals during production, transportation, storage and use caused by zero addition of anti-caking agents in the prior art.
[0006] The technical solution of the present application is as follows:
[0007] A green edible salt production process, comprising the following steps:
[0008] A: The finished salt is subjected to secondary cooling before packaging. The finished salt is introduced into a secondary cooler after coming out of the salt device dryer, and the temperature of the finished salt is reduced to near room temperature by circulating desalted water;
[0009] B: The finished salt particles cooled in step A are sieved, and the sieve oversize with relatively large particle size and less prone to caking are selected;
[0010] C: Iodine is added to the finished salt cooled and sieved in step B;
[0011] D: The finished salt in step C is stored for a period of time before packaging;
[0012] E: The finished salt is packaged using a packaging material with strong barrier properties and good sealing performance.
[0013] As a further technical solution, the secondary cooling of the finished salt in step A adopts a powder flow cooling process, and the cooling equipment adopts a powder flow plate cooler.
[0014] As a further technical solution, in the powder flow plate cooler, the hot phase (finished salt) flows from the top to the bottom of the equipment by gravity when the material is at full level, and exchanges heat with the cold phase (circulating demineralized water) flowing from bottom to top for cooling.
[0015] As a further technical solution, the powder flow plate cooler uses circulating demineralized water as the cooling medium and maintains a relatively constant temperature at the inlet and outlet of the cold phase.
[0016] As a further technical solution, the demineralized water is heated and then cooled by circulating cooling water for heat exchange.
[0017] As a further technical solution, cold and dry air is introduced into the lower end of the powder flow plate cooler.
[0018] As a further technical solution, an exhaust port is provided at the upper end of the powder flow plate cooler.
[0019] As a further technical solution, in step B, the cooled finished salt particles are screened to select raw salt with a standard particle size range. After screening, the proportion of standard particle size is required to be above 90%.
[0020] As a further technical solution, in step C, an iodine agent is added to the finished salt, that is, after the finished raw salt is cooled down, potassium iodate solution is sprayed into the mixer.
[0021] As a further technical solution, in step D, the finished salt is stored for a certain period of time before packaging, and an open bucket elevator is installed in the storage silo to allow the salt to circulate within the silo, thereby breaking up false agglomerations and keeping the salt temperature as close as possible to the ambient temperature.
[0022] The working principle and beneficial effects of this invention are as follows:
[0023] 1. The salt is cooled twice before packaging to bring the packaging temperature down to near ambient temperature, thereby minimizing the adsorption or release of moisture by the granular salt and preventing clumping. This ultimately solves the problem of clumping during transportation, storage and use after packaging.
[0024] 2. The cooling process adopts a plate-type solid powder flow cooling process. On the one hand, the plate solid-liquid heat exchange efficiency is high. On the other hand, the natural drop of edible salt is used to overcome the external force of transportation. Compared with the traditional drum or fluidized bed process, it has more energy-saving and environmental protection advantages.
[0025] 3. Screen the semi-finished salt particles to select raw salt with relatively larger particle size, higher quality and less tendency to clump.
[0026] 4. Adding iodine after cooling, compared to adding iodine before cooling, can prevent the loss of iodine due to evaporation with moisture caused by high temperature.
[0027] 5. Before packaging, leave the salt crystals in a storage silo for a certain period of time to allow the surface moisture of the salt crystals to evaporate slowly and completely;
[0028] 6. Before packaging, the pseudo-agglomeration is broken up, and the surface morphology of sodium chloride crystals is changed, effectively reducing the contact area between particles, thereby preventing or delaying agglomeration. An open bucket elevator is installed in the finished salt silo. The salt is continuously lifted from bottom to top by the elevator in the silo, and the tangential salt inlet angle is maintained at 30-45°. The increased mechanical force keeps the salt in a loose and flowing state, thereby breaking up the pseudo-agglomeration of the finished salt. Attached Figure Description
[0029] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0030] Figure 1 This is a flow chart of the green edible salt production process of the present invention;
[0031] Figure 2 This is a schematic diagram of the structure of the bucket elevator in the silo for green edible salt production according to the present invention. Detailed Implementation
[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0033] like Figure 1 As shown, a green edible salt production process includes the following steps:
[0034] A: The finished salt undergoes secondary cooling before packaging. After exiting the dryer of the self-made salt production device, the finished salt enters the secondary cooler, where the temperature of the finished salt is reduced to close to room temperature through circulating demineralized water.
[0035] B: Screen the finished salt particles that have been cooled in step A, and select the particles with relatively large particle size that are not easy to clump together.
[0036] C: Add iodine to the finished salt that has been cooled and sieved in step B;
[0037] D: The finished salt in step C is stored for a period of time before packaging;
[0038] E: Use packaging materials with strong barrier properties and good sealing performance for packaging.
[0039] To address the clumping problem in the production, transportation, storage, and use of green edible salt caused by the absence of added anti-caking agents, this embodiment employs a two-stage cooling process before packaging to lower the salt packaging temperature to near ambient temperature; pre-addition sieving to ensure salt crystal purity and particle size; post-cooling iodine addition to prevent iodine loss; ensuring a certain storage time before packaging; and using an open bucket elevator in the storage silo to circulate the salt product within the silo, thus delaying and breaking down pseudo-caking, ultimately resolving the clumping problem of green edible salt with zero added anti-caking agents; finally, packaging with strong barrier properties and good sealing performance to isolate the finished product from the outside air as much as possible, extending the salt clumping cycle, thereby producing green edible salt with zero added anti-caking agents and achieving the effect of preventing clumping.
[0040] After exiting the dryer of the self-made salt production equipment, the finished salt (with a particle size of 0.15mm-0.85mm, a temperature of 60-65°C, a specific heat of 3.6kcal / kg / ℃, and a moisture content of <0.1%) enters the secondary cooler.
[0041] In step A, the secondary cooling of the finished salt adopts a powder flow cooling process, and the cooling equipment adopts a powder flow plate cooler with high heat exchange efficiency.
[0042] In a powder flow plate cooler, the hot phase (finished salt) flows from the top to the bottom of the equipment at full level by gravity, exchanging heat with the cold phase (circulating demineralized water) flowing from the bottom to the top for cooling.
[0043] This ensures that the finished salt can be evenly distributed, improves the speed of heat conduction, enhances the heat exchange and cooling effect, and ensures that the finished salt can be cooled evenly as a whole.
[0044] The powder flow plate cooler uses circulating demineralized water as the cooling medium and maintains a relatively constant temperature between the inlet and outlet of the cold phase. On the one hand, this can prevent excessive temperature difference between the hot and cold phases, which could cause localized overcooling on the hot phase (finished salt) side to reach the air dew point, resulting in condensation and crystallization, adhesion, bridging, and blockage. On the other hand, it can prevent scale blockage caused by heating when using ordinary cooling water.
[0045] After the demineralized water is heated, circulating cooling water is used for heat exchange to ensure the cooling effect of the demineralized water. After the finished salt is cooled, it is close to the ambient room temperature, preferably about 5°C higher than the ambient temperature.
[0046] Cold, dry air is introduced into the lower end of the powder flow plate cooler to disturb the flowing finished salt, so as to remove the moisture generated by the cooling of the finished salt and ensure that the finished salt is isolated from the outside air during the cooling process.
[0047] The cold, dry air should be thoroughly degreased and dehumidified to ensure a low dew point temperature, ideally around 5°C below the local temperature (the exact temperature may vary depending on the local climate).
[0048] The powder flow plate cooler is equipped with an exhaust port at the top to promptly remove the moisture-laden air generated during the cooling of the finished salt product.
[0049] In step B, the cooled finished salt particles are sieved to select raw salt within the standard particle size range. After sieving, the standard particle size ratio is required to be above 90%.
[0050] In this embodiment, the standard particle size range is 0.55mm-0.85mm;
[0051] Before adding iodine, the finished salt particles are screened to select the larger particles that are less prone to clumping, thus ensuring the particle size and quality of the finished salt.
[0052] Further optimization is needed, ensuring that the proportion of 0.55mm-0.85mm particles in the finished salt after sieving is above 90%;
[0053] Further optimization requires that the sodium chloride content of the sieve residue of the finished salt be guaranteed to be 99.6% or higher, while the undersize residue be used as industrial salt.
[0054] In step C, iodine is added to the finished salt, that is, potassium iodate solution is sprayed into the mixer after the finished raw salt has been cooled down.
[0055] Adding iodine after cooling ensures that the iodine is not lost. After the finished raw salt is cooled down, potassium iodate solution is sprayed into the mixer. Compared with adding iodine before cooling, this can prevent the iodine from being lost due to evaporation of water at higher temperatures.
[0056] In step D, the finished salt is stored before packaging to ensure a certain residence time. An open bucket elevator is installed in the storage silo to allow the salt to circulate within the silo, so that the salt temperature is as close as possible to the ambient temperature. The salt is continuously lifted from bottom to top by the elevator in the silo, while maintaining a tangential salt inlet angle of 30-45° to increase the mechanical external force and keep the salt in a loose and flowing state, thereby breaking the false agglomeration of the finished salt.
[0057] Further optimization involves ensuring a certain storage time before packaging the finished salt, allowing the surface moisture of the salt crystals to evaporate slowly and fully, thereby reducing the possibility of salt particles clumping. In particular, the storage time before packaging the finished salt should be 24-48 hours, with the temperature dropping to near the ambient temperature.
[0058] In step E, after secondary cooling, particle sieving, addition of iodine, and storage in a warehouse for a certain period of time, the finished product is packaged using packaging materials with strong barrier properties and good sealing performance. Good sealing packaging can effectively block moisture and extend the shelf life of the salt.
[0059] In this embodiment, the green edible salt produced using this production process contains zero anti-caking agents, eliminating the intake of anti-caking agents from the source. It fully complies with the national standards GB2760 "Hygienic Standard for the Use of Food Additives" and NY / T1040 "Green Food Edible Salt". It can also ensure that the product can be stored for more than 12 months without obvious clumping. On the basis of meeting the green food edible salt standards, it achieves the effect of preventing clumping and facilitating storage.
[0060] 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 green edible salt production process, characterized in that, Includes the following steps: A: The finished salt undergoes secondary cooling before packaging. After exiting the dryer of the self-made salt production device, the finished salt enters the secondary cooler, where the temperature of the finished salt is reduced to close to room temperature through circulating demineralized water. B: Screen the finished salt particles that have been cooled in step A, and select the particles with relatively large particle size that are not easy to clump together. C: Add iodine to the finished salt that has been cooled and sieved in step B; D: The finished salt in step C is stored for a period of time before packaging; E: Use packaging materials with strong barrier properties and good sealing performance for packaging.
2. The green edible salt production process according to claim 1, characterized in that, In step A, the secondary cooling of the finished salt adopts a powder flow cooling process, and the cooling equipment is a powder flow plate cooler.
3. The green edible salt production process according to claim 2, characterized in that, In a powder flow plate cooler, the hot phase (finished salt) flows from the top to the bottom of the equipment under gravity when the material is at full level, and exchanges heat with the cold phase (circulating demineralized water) flowing from the bottom to the top for cooling.
4. The green edible salt production process according to claim 3, characterized in that, The powder flow plate cooler uses circulating demineralized water as the cooling medium and maintains a relatively constant temperature at the inlet and outlet of the cold phase.
5. The green edible salt production process according to claim 4, characterized in that, After the demineralized water is heated, it is cooled by circulating cooling water for heat exchange.
6. The green edible salt production process according to claim 5, characterized in that, Cold, dry air is introduced into the lower end of the powder flow plate cooler.
7. The green edible salt production process according to claim 6, characterized in that, The powder flow plate cooler has an exhaust port at the top.
8. The green edible salt production process according to claim 1, characterized in that, In step B, the cooled finished salt particles are sieved to select raw salt with a standard particle size range. After sieving, the proportion of standard particle size is required to be above 90%.
9. The green edible salt production process according to claim 1, characterized in that, In step C, iodine is added to the finished salt, that is, potassium iodate solution is sprayed into the mixer after the finished raw salt has been cooled down.
10. The green edible salt production process according to claim 1, characterized in that, In step D, the finished salt is stored for a certain period of time before packaging. An open bucket elevator is installed in the storage silo to allow the salt to circulate within the silo, breaking up false agglomerations and keeping the salt temperature as close as possible to the ambient temperature.