Ultrafine aluminum hydroxide is aluminum hydroxide product with particle size D50 = 1μm ~ 2μm. It has wide particle size distribution, high whiteness and stable chemical composition. It is widely used in flame retardant industry such as wire and cable, electric circuit board, rubber and plastic industries .
  1 process description
  The sodium aluminate refined liquid was cooled to a certain temperature through a plate heat exchanger, passed into carbon dioxide, and controlled the decomposition temperature, the aeration speed and the decomposition time to prepare a seed slurry. Seed slurry after aging for some time, and
  Cold semen mixed in a certain proportion, control the temperature, time for a period of seed decomposition. A section of decomposition liquid, cold semen and then a certain percentage of mixed reaction, the second stage of seed decomposition, control the decomposition temperature, decomposition time, decomposition rate, to obtain ultrafine aluminum hydroxide slurry. Ultrafine aluminum hydroxide slurry through the belt filter separation, filtration, washing, beating tank into the beating. After the spray drying tower drying, into the cyclone dust collection and bag filter, and then through the pin mill crusher, into the second set of cyclone and bag filter, and finally into the finished product warehouse for packaging.
  2.1 species decomposition temperature is the impact of product size factor
  Larger product size fluctuations, the median diameter of the largest 2.0μm, the smallest 1.3μm, the main reason for such a result is due to feed temperature control is not good, caused by large fluctuations. Decomposition temperature has the trend of coarse grain size, after strengthening the control of technical indicators, strict control of the decomposition temperature, product size tends to be stable.
  2.2 The amount of seed added to the product size
  The amount of seeds on the particle size also has a greater impact, the greater the amount of seeds, the smaller the product, otherwise thicker.
  2.3 black spots in the product reason
  Black spots in the product are: a variety of reaction tanks, decomposition tank corrosion, pipe scarring, raw materials into the filter into the water and so on. For magnetic black spots can be strengthened in the relevant places magnetic bar, impurity removal effect is significant.
  2.4 for the product with alkali control
  As ultra-fine aluminum hydroxide product size, filtration and washing more difficult, we use the belt filter separation and filtration and washing, as long as the choice of a good filter cloth, the filter effect is good, the product with alkali within the range of indicators.