The vacuum crystallizer has some unique and excellent performances, because in the practical application, the latent heat of vaporization consumed by the solvent evaporation is mainly achieved through the sensible heat released by the solution cooling and the crystallization heat of the solute. Therefore, in the vacuum crystallizer, the solution is cooled without contact with the cooling surface, and the solution is vaporized without setting the heat exchange surface, thereby avoiding the disadvantage of generating a large amount of scale in the apparatus.
For the user, the correct operation of the vacuum crystallizer is also very important in order to ensure a good crystallographic effect. Next we will briefly introduce its operating procedures for everyone. Before you start the equipment, you need to do some preparations.
Before the vacuum crystallizer is turned on, the main preparations are as follows: 1. Check and confirm that public utilities such as water, electricity, steam, and meters can meet the process requirements; 2. Confirm that the equipment, electricity, instruments, pipelines, and valves are in good condition. 3, open the steam sub-cylinder drain valve drain the condensate of the clean cylinder to ensure that the steam pressure in the specified value; 4, close the mold discharge valve, exhaust valve, the top vent valve.
When the inspection is completed and no abnormality is confirmed, the vacuum crystallizer can be turned on to operate as required. In this process, the staff needs to turn on the condensate and maintain the specified flow rate. Next, the water ring vacuum pump is turned on so that the pressure in the crystallizer reaches the specified value; then, the feed valve at the bottom of the crystallizer is opened, and the feed reaches the total feed. At 1/4 of the time, the crystallizer stirs.
After the feed cycle is completed, the feed valve should be closed in time. Then gradually reduce the temperature of the material to the specified range. When the temperature drops to a certain value, the steam ejector valve of the vacuum crystallizer is slowly turned on, fully opened after 5 minutes, the steam flow is adjusted, and the circulating water valve of the vacuum crystallizer is opened at the same time until the maximum value is reached.