Ammonium bromide crystals have strong hygroscopic properties. When the environmental water vapor partial pressure is higher than the equilibrium water vapor partial pressure on the surface of the salt crystal, the material will adsorb moisture from the air, and the crystal surface will dissolve to form a liquid film; Subsequent fluctuations in environmental temperature and humidity will cause the liquid film to crystallize again, and the crystals will adhere to each other, forming clumps. To reduce clumping, it is necessary to implement multi-dimensional control measures including temperature and humidity control in the production process, protection of finished product packaging, warehouse environment management, and material management.
1、 Temperature and humidity control in the production process
1. Crystallization, centrifugation, and drying sections
      The drying process is a key control point. The drying stage requires controlling the material discharge temperature, and the material cooling process cannot be directly exposed to the air in ordinary workshops. The material is highly susceptible to rapid moisture absorption when exposed to room temperature and high humidity air at high temperatures. The cooling area needs to be equipped with an independent space, and it is recommended to control the relative humidity of the environment within 45% and maintain an ambient temperature of 20-26 ℃.
      The dried ammonium bromide must be thoroughly cooled to near ambient temperature before screening and packaging; High temperature materials are directly packaged, and condensed water vapor will form inside the bag, causing the material to deliquesce and clump inside the packaging bag.
2. Screening, mixing, and packaging clean room
      The packaging station belongs to a high-risk section and requires independent temperature and humidity control. Recommended ambient temperature is 20-25 ℃, with relative humidity control of ≤ 40%~45%. The workshop can be equipped with dehumidification units to reduce the moisture content in the air; Simply cooling down cannot achieve the desired effect, the key is to lower the air humidity.
      Try to shorten the exposure time of materials in an open packaging state, reduce the contact time between crystals and humid air, and avoid surface adsorption of water vapor. The packaging equipment should be well sealed and protected to reduce the intrusion of humid air from the outside into the operating area.
2、 Temperature and humidity management of finished product warehouse
1. Basic environmental parameters of the warehouse
      The storage environment should prioritize maintaining a stable temperature of 18-26 ℃ and a relative humidity control of ≤ 45%. Humidity is the core indicator, and the higher the humidity, the faster the absorption rate of ammonium bromide; At the same time, avoid significant fluctuations in warehouse temperature day and night. Changes in temperature can cause condensation of air inside the packaging, and even if the external humidity meets the standard, water vapor will still be generated inside the bag.
      The warehouse is equipped with online temperature and humidity monitoring equipment, with sensors arranged at multiple locations to continuously record data; Start the dehumidification equipment when the humidity exceeds the standard. Avoid ventilation blind spots, wall moisture regain, and ground water seepage in certain areas of the warehouse.
2. Warehouse layout management
      Materials should be stacked away from walls and floors, and stored on pallets to prevent direct contact with the ground and prevent moisture from seeping upwards. Stay away from warehouse doors, windows, drainage pipes, air conditioning vents, and other locations that are prone to condensation.
      Avoid the intersection of cold and hot air flows in the warehouse to reduce the risk of condensation; Reduce the frequency of warehouse opening during rainy weather to prevent a large amount of high humidity air from entering the warehouse.
3、 Packaging supporting measures (in conjunction with temperature and humidity control to reduce the probability of clumping)
      Temperature and humidity control need to be coordinated with packaging sealing schemes, otherwise the effect of simply controlling humidity is limited.
      Select low moisture permeable composite packaging materials, perform sealing and sealing treatment to prevent water vapor penetration. Partial working conditions can adopt a double-layer packaging structure.
      Fill the packaging as much as possible to reduce the empty space inside the bag and lower the moisture content of the air inside the bag; Before packaging, the air inside the bag can be replaced (optional dry nitrogen replacement) to reduce the moisture content inside the bag.
4、 Auxiliary management methods
      1. Materials follow the first in, first out principle to shorten storage cycles. The longer the storage time, the slower the water vapor penetrates and accumulates, and the probability of clumping gradually increases.
      2. Reduce excessive stacking of materials, as the self weight pressure of the upper layer of materials will accelerate the squeezing and bonding of slightly deliquescent crystals, exacerbating clumping. Control the number of stacking layers.
      3. Conduct regular inspections, spot check the appearance of packaging, and inspect for any signs of packaging damage, bulging, or moisture; Damaged packaging needs to be repackaged in a timely manner.
      4. The production and storage environment should avoid frequent and significant fluctuations in temperature and humidity. A stable environment is more important than simple low temperature or low humidity, and repeated fluctuations in humidity are important triggers for agglomeration.

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