Performance of phosphogypsum hollow blocks produced by semi dry method
To promote the large-scale utilization of phosphogypsum,semi dry method was independently developed for produc-ing phosphogypsum hollow blocks.This paper compared the process of self-developed semi dry method with traditional pouring method,and introduced the process,principle,and product performance of the phosphogypsum hollow blocks of semi dry method.This experimental study shows that the initial moisture content of phosphogypsum hollow blocks prepared by the semi dry method during demolding is 23.06%,much lower than that produced with traditional pouring method,and it is in a dry state on the 6th day.The fracture load and compressive strength exceed the basic requirements of the standard JC/T 698-2010"Gypsum Block"during the offline stacking process.It increases linearly after 24 hours,slightly decreases due to moisture regain from 24 hours to 72 hours,and gradually increases and stabilizes after 144 hours.The product should be palletized offline for 24 hours or loaded onto a truck for transportation to users after the 3rd day,without the need for drying;Products produced in summer should be ap-propriately sprayed within 2 hours after demolding.For general product production,dihydrate gypsum(waste product powder)can be added and used appropriately.It is best to be used after the third day of product production.