The lab has several options for measuring fines and densities of granular materials.

BET-Test

The procedure named after Brunner-Emment-Teller is applied for precise determination of the specific surface area of solid mater by means of gas adsorption. The measurement of the so-called BET surface of powders, granulates and porous materials uses a gas like helium or nitrogen for which the mix proportion fine automatically adjusted by using a mass-flow-valve. A thermal conductivity sensor measures the quantity of gas adsorbed or desorbed. The test is based on the quantitative determination of the adsorbents or the adsorptive which is necessary for covering completely the outer and the freely accessible inner surface of the solid sample with a monolayer of the adsorbent.

Air-permeability measurement according to Blaine

Measuring the air-permeability is applied in order to determine the grinding fines of a powder-like substance a porous system is manufactured of defined mass end porosity out of the solid matter under investigation. This compacted material sample has a flow resistance for gas which is proportional to its surface.

Density of powders

The gas pycnometer is used for measuring the density of solid powder-like materials. The test gas helium fills even smallest pores (pore diameter 10^-10 m).

Density of aggregates

Capillary of flask pycnometer for measuring the particle density of aggregates.