agglomeration 2

I’ll hazard a little more as the first bit seemed well received.

Knowledge of the need for correct agglomeration leads to why a higher grade of acid isn’t an issue yet. The balling the silica, pet coke and apatite (main phos. mineral) is intended to achieve two purposes.

Firstly the pet coke, source of carbon that can be oxidized to CO & CO2 reducing the apatite (carbonate) to let off P2O5 gas is intimately mixed with the apatite and silica. (With the parallel to iron ore the Coke allows the CO & CO2 generated to reduce the Fe2O3 down to Fe).

Secondly there is a good level of porosity in the pellets allowing oxygen and hot gasses to percolate easily through the pellets and react quickly. The porosity and permeability of well formed pellets is well above that of solid rock as mined. If the pellets are breaking down the heated gasses can’t pass through the pellets and effectively roast off the P2O5 gas. You get insufficient reaction, some P2O5 coming off getting doused with water and getting a weak solution of Phosphoric acid.

The good news is the JDC guys say they have already got the right temperature profile along the kiln in the correct ones. Part of the reason why the kiln is ported i.e. Has ports to control different sections.

These guys know what good pellets with adequate porosity looks like. They are adjusting the mixer and pelletizing mix to get it right. Getting that right could bring results relatively quickly. That’s why I opined they’ll learn from the experience.

Again I hope I haven’t rabbited on too much.