the agricultural milk 600 was added to the mixing kettle by calcium salt preheating method. In addition, the dodecyl benzene calcium carbonate is dissolved in the preheater with ethanol, and preheated to about 80 ℃, and the castor oil polyoxyethylene in the mixing kettle is stirred and heated to about 120 ℃. Vacuum decompression, drop the preheated calcium salt alcohol solution under high vacuum degree, make the two evenly mixed after dropping, continue to dealcoholize dehydration for 1 h, the temperature should be 120~130 ℃. Take samples and stop decompression after checking the moisture. Add 190 kg xylene and continue stirring for 15 min.
In the mixed feeding method, the agricultural milk 600 and the ethanol solution prepared with calcium alkylbenzene sulfonate are sequentially added to the mixing kettle, heated under stirring, vacuumed, dealcoholized, and dehydrated until the water content meets the quality standard, Add xylene and stir well.
Calcium salt solution concentration method: calcium dodecane benzene sulfonate is prepared into 60% ethanol solution and added to the mixing kettle. Under stirring, the temperature is raised, degreased under reduced pressure, and dehydrated to increase the calcium salt content to 75%. Then add the agricultural milk 600, stir evenly, continue to remove alcohol, dehydrate until it meets the standard, then add xylene, and stir evenly.
The above three methods are all batch methods, and the mixing time of method 2 is too long. When the amount of calcium salt solution is large, a large amount of foam is generated during dealcoholization, and it is difficult to remove alcohol water. Method 3 is prone to wall sticking. Method 1 is widely used.
The 60% ethanol solution of agricultural milk 600 and calcium dodecyl benzene sulfonate was added to the mixing kettle by semi-continuous method and preheated to 50 ℃. Vacuum is sucked into the thin film evaporator, dehydrated at 0.08 MPa, and the outlet temperature is controlled at 88~124 ℃. The stability was measured after discharge. If the lack of castor oil polyoxyethylene ether is directly supplemented and calcium salt is deficient, further dealcoholization and dehydration are required after supplementation.