Permeable porosity of refractory castables evaluated by the water-expulsion porosimetry technique

In this work, the water-expulsion porosimetry technique was used to quantif y the permeable pores of self-flow ultralow-cement refractory castables tha t were treated at 600 degrees -1650 degreesC. Results have shown that the m ethod as proposed in previous works was not valid, because water was not re moved continuously from pores, relative to increased pressure, Nevertheless , the maximum pore diameter obtained according to ASTM Method E128-89 could be successfully correlated with other castable physical properties (such a s the permeability constants from the Forchheimer equation) and the apparen t porosity obtained via the Archimedes technique. Although the apparent por osity decreased as the thermal treatment temperature increased, the pore mo rphology changed continuously, with the generation of less-tortuous and mor e-permeable paths for fluid flow.