OSLO type evaporative crystallizer, also known as Oslo crystallizer, was proposed by Norwegian Jeremiassen in the 1920s, and is also often called Krystal crystallizer or particle size classification crystallizer.
OSLO type evaporative crystallizer, also known as Oslo crystallizer, was proposed by Norwegian Jeremiassen in the 1920s, also commonly known as Krystal crystallizer or particle size classification crystallizer, which has been widely used in industry. As shown in the figure below, its main feature is that the region generated by supersaturation and the crystal growth area are respectively set in two places of the crystallizer, and the crystal is fluidized and suspended in the circulating mother liquid flow, providing a good condition for crystal growth.
Scope of application
OSLO type evaporative crystallizer application industry: MSG, metallurgy, water product processing, soft water manufacturing, etc.
OSLO is a typical crystallizer used in the salt industry. The characteristic is that the solution flows out from the upper part of the crystallizer, enters the forced circulation pump, enters the center downcomer of the crystallizer through the device that can make the solution supersaturate, gradually forms crystallization, and the grown crystallization sinks in the bottom of the crystallizer and is taken out as a product.
In the process of material circulation, the crystal does not participate in the cycle, so it is not easy to be broken, the crystal is removed from the middle of the crystallizer without settlement restrictions, the crystal growth environment is good, so the crystal particle size is large, up to 6-20 mesh, that is, 3mm. No stirring is required in the crystallizer.
Device characteristics
1. The bottom of the incubator is a circular arc, which improves the flow state of the feed liquid in the incubator and does not form a dead zone;
2. The expanded section of the upper part of the brooder can make the salt crystals settle down, do not participate in the cycle, and reduce the chance of secondary nucleation;
3. The feed liquid is fed from the lower part of the evaporation chamber and discharged from the upper center pipe, which reduces the short-circuit temperature difference loss. At the same time, there is a particle dissolution process when the feed liquid rises in the evaporation chamber, and the feed liquid changes from unsaturated to saturated, which can reduce the number of fine crystals and ensure the particle size of the salt;
4. The mother liquor discharge pipe is set in the upper cone of the incubator during the design, which can not only discharge mother liquor to control the content of Na2 SO4 in the tank, but also discharge some fine salt crystals into the system to keep the crystal nuclei in the tank relatively stable and facilitate the growth of salt grains;
5. In the design, it is also considered that the brushing method of retaining the feed liquid in the brooder every time the tank is brushed, which only brushes the heating chamber, so as to avoid the loss of large grain salt in the brooder tank, and the time to restore the production of qualified salt after brushing the tank can also be shortened.
6. The circulating pump motor uses an adjustable motor to adjust the flow rate of the circulating pump by adjusting the motor speed, so as to adjust the salt grain diameter in the circulating liquid and the number of crystals in the discharge system.
