Ammonium phosphate dibasic CAS NO.7783-28-0

Feed with wet process phosphoric acid for raw material production of diammonium hydrogen phosphate, its production process should be defluorinated through two steps, three sections ammonification, and three ammonium phosphate pyrolysis for feed materials diammonium hydrogen phosphate. The production cost is lower than the method using yellow phosphorus as raw material.

Wet-process phosphoric acid method will contain 20% ~ 30% P2O5, 1.2% ~ 2% F the extraction of phosphoric acid, the gas purification system to the reaction device and forms through three sections of ammoniation make impurities easily filter sediment, the sediment separation by filter press, the filtrate for containing P2O5 < 15%, F0.4 %, SO42-2.5% ~ 3% and about 1% of suspended solid diammonium phosphate solution, in order to further removal of dissolved impurities and part of suspended solids, the filtrate into another reaction device zhongtong ammonia saturation, again into the cooling mold cooling crystallization, generate three ammonium phosphate crystallization. The crystallization is separated from the mother liquid by cone sedimentation tank, and then dehydrated by centrifugal process. The crystallization is put into the boiling furnace to be pyrolyzed into diammonium phosphate. After drying, the finished product of diammonium phosphate is made

H3PO4 + 2 nh3 - (NH4) 2 hpo4

(NH4) 2 hpo4 + NH4OH and 43 po4 + H2O (NH)

(NH4) 3 hpo4 3 h2o / 70 ℃ - (NH4) 2 hpo4 + NH3 + 3 h2o

The mixed gas containing diammonium phosphate dust and ammonia gas is removed by cyclone separator and then absorbed by wet phosphoric acid spraying in the scrubber.