Method for determining the amount of volatile surface liquid on a solid extrudate

Samenvatting

The present invention relates to a method for determining the amount of volatile surface liquid on a solid extrudate obtainable by forcing a mixture comprising a solid and a volatile liquid through an opening, the method comprising: a) providing a chamber with a gas inlet and a gas outlet; b) filling the chamber with a packed bed of the solid extrudate, wherein the packed bed has a weight m1; c) continuously flowing a gas at a gas flux Q through the packed bed from the gas inlet to the gas outlet, wherein the gas has a temperature T1 at the gas inlet and a temperature T2 at the gas outlet, and wherein the volatile liquid has a partial vapour pressure p1 in the gas at the gas inlet and a partial vapour pressure p2 in the gas at the gas outlet, and wherein the packed bed has a weight m2; d) determining p2 as a function of time during c); e) measuring m2 and/or T2 as a function of time during c); f) calculating the amount of the volatile liquid evaporated during the time the partial vapour pressure p2 is equal to the saturation vapour pressure of the volatile liquid in the gas. The invention further relates to use of such method in a process for manufacturing a solid extrudate, and to a process for manufacturing a solid extrudate comprising such method.