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The present research work involved cleaning contaminated acid resistance refractory brick waste, i.e. that which was in direct contact with the furnace contents. The waste acid resistance brick was obtained from the sixth furnace of Misrata Iron and Steel Complex. The waste brick was crushed to 30 mm size granules, and further ground by hammer milling to 1 mm. The 1 mm sized powder was sieved to give over-sized (+0.355 mm) waste powder. The over-sized powder (+0.355 mm) was subjected to high energy ball milling to produce Nano-powder with particles sizes ranging from 45 to 51 nm. Three powder batches were prepared. Each powder batch was made up of three components; brick waste Nano-powder, coarse over-sized (+0.355 mm) waste brick powder, and 75 micron-sized local Sebha Kaolin clay. All powder batches had equal fractions of coarse waste powder and kaolin clay. These powder batches were pressed, in a semidry state, at a pressure of 100 Pa. The powder batches were then dried at a temperature of 110˚C before being fired at 1000, 1300, and 1500˚C to produce shaped final products. Characterization of starting refractory waste bricks, waste coarse powder, Sebha kaolin clay, and waste Nano-powder using the technique of X-ray diffraction analysis (XRD) was carried out. The work also involved the measurement of physical properties; bulk density, porosity, and volume shrinkage of waste bricks and sintered final products. Melting of a glassy phase was observed at the firing temperature of 1500˚C. The presence of this phase had a negative effect on the physical properties. Hence, based on the obtained results of the present research work, this limited the recommended maximum working temperature of the produced bricks to 1300˚C. The inclusion of 30 % of Nano-sized powder particles as a component in the refractory powder batches had the most enhancing effect on the physical properties of bulk density, volume shrinkage, and porosity of the final shaped products fired at 1300˚C. This would mean that the most suitable refractory brick powder batch is 35: 30: 35 with the local Sebha kaolin clay playing the role of a good binding material.
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