DRAINABILITY Schopper-Riegler

This test is performed to determine the drainability of a pulp according to the Schopper-Riegler method.

Operate the instrument in accordance with ISO 536 and the manufacturer’s instructions.

Soak 24 g of dried pulp (one sheet) at least 4 h in 1200 ml of distilled water at 20°C.

Dilute to 2000 ml with distilled water at 20°C and disintegrate for 30.000 revolutions.

Dilute to about 0,22% a sufficient portion of the disintegrated pulp and determine its concentration by filtering, drying at 105±3°C and weighing.

Wet the drainage chamber with distilled water at 20,0±0,5°C and keep it at such a temperature.

Dilute a volume of the prepared stock containing 2,00±0,02 g of pulp to 1000±5 ml with distilled water at 20,0±0,5°C.

Pour it in the tester and after 5 s release the cone valve.

For everything not specified here refer to ISO 5267-1.

Report 5 measures in SR units, their mean and standard deviation calculated to 3 significant figures.