It has been suggested that the dihydrate process be used in the place where power cost is cheap; semihydrate process be used in the place where factory is near to phosphorus mine; and simple and convenient operation is required; semi-dihydrate process be used in the place where both material and power are expensive.

The experimental data about decomposition of carbon dioxide hydrate at different temperatures and pressures are obtained using this apparatus.

Production control of phosphoric acid by dihydrate process;