PHOSPHORUS RECOVERY FROM SEWAGE-SLUDGE MOLTEN SLAG USING A COMBINATION OF ACID-DISSOLUTION, ALKALI-PRECIPITATION, AND ION-EXCHANGE

We recently reported an efficient procedure for recovering phosphoric acid from dephosphorization slag. This recovery consists of a combination the following four processes: (1) A first dissolution process slag in nitric solution; (2) precipitation then adds ammonia to obtained eluate; (3) second dissolves and, (4) final involves ion exchange which eluate is passed through resin. In present study, this was applied concentrate and recover phosphorus sewage-sludge molten slag, unused resource that should be considered new phosphorus. As result, our viable two revisions. Initially, time extended 0.2 h 1 h, but proved optimum Next, we discovered it better perform filtration one day after adding instead immediately it. The other processes could treated under substantially same conditions as case high-purity obtained.