Investigations in the development of self-flowing basic castables

The general trend toward the use of self-flowing castables in high-temperat ure plant is based on the development and use of self-flowing basic bodies based on MgO or MgO spinels, respectively. A targeted use of dispersing age nts can reduce the hydration tendency of MgO effectively. The use of sinter magnesia in the coarse grain range and fused magnesia in the ultra fine gr ain range results in an optimised solution for the lattice grain. For the b inder matrix, the use of a reactive alumina mixture is well-suited, one wit h which the MgO almost completely reacts forming spinel. Observing the grai n distribution of the ultrafine grain portion, self-flowing bodies can be a chieved with an amount of slump equal to 100 %, having 8 % moisture content . These bodies containing 70 % MgO result in the highest level of microstru ctural formations and high temperature properties when dried and pre-fired at 850 degreesC and 1500 degreesC respectively. The bodies should be able t o be used at temperatures significantly above 1500 degreesC.