| Abstrakt: |
This work aims at improving the energy utilization efficiency of kilns. Magnesium aluminate spinel porous insulation materials were prepared as follows. Medium-grade magnesia fine powder and calcined alumina powder were mixed in a mass ratio of 35:65, dried, and crushed into powders of d50 =2.3 µ xm. Then different amounts of sodium carboxymethyl cellulose (CMC) as a foam stabilizer and 0.6 mass% potassium oleate as a foaming agent were added to obtain the foaming slurry. Finally the slurry was injected into molds of 40 mm x 40 mm x 40 mm, demolded, dried at 110 °C for 24 h, and fired at 1 500 °C for 3 h. The effects of the CMC addition (0, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5%, by mass, extra adding) on the properties of the slurry and the fired samples were studied. The results show that: (1)when the CMC addition is higher than 0.1%, the slurry has decreased expansion ratio, increased viscosity, and less and smaller bubbles; (2) when the CMC addition is 0.2%, the slurry has the maximum Zeta potential absolute value of 18.3 mV, which is the most stable; the sample has the most pores, which are spherical and closed; the apparent porosity, bulk density, and cold compressive strength of the sample are 73.5%, 0.95 g • cm-3, and 13.1 MPa. [ABSTRACT FROM AUTHOR] |
