Tieling Zhaohui Energy Saving Technology Development Co., Ltd.

Technical instructions of complexation magnesia alumina binder applied in mass production of RH chrome-free magnesia based unfired bricks

Formulation:

Recommended addition of refractory brick aggregates: 70% (0-6mm; Fe<1%, Si<1%, Ca<2% by mass)

Recommended addition of refractory brick fines: 30% (180-200mesh)

Complexation magnesia alumina binder: 3.5%-4% (extra-adding or real portion)

The metal aluminum shall be added along with the fines, not lower than 3%.

Charging order:

Particles (aggregates) → adding water (producing wettability) →adding binder (producing adhesiveness) → adding fines

Detailed procedures

Feed 70% of refractory brick aggregates into a mixer; turn on the mixer; add 1.8% of water (the water absorption of aggregates shall be considered and producing proper wettability is the goal); pre-mix for 2-3min (judge the wettability by the hand feel); add 3.5%-4% of complexation magnesia alumina binder powder, mix for 5-7 min (judge the adherence by the hand feel); add 30% of refractory brick fines and mix for 10-11min. The humidity shall be appropriate for the brick shaping. The green bricks are dried at 100 ℃-200 ℃ for 48h in a drying kiln. The residual water shall be less than 1%.

Notes:Metal aluminum and water in the mixture will not react because water has been absorbed 

Tieling Zhaohui Energy Saving Technology Development Co., Ltd.

Properties of RH chrome-free unfired bricks bonded by complexation magnesia alumina binder

Properties of MgO based unfired bricks bonded by complexation magnesia alumina binder