Preparation of insulating firebricks using date seeds

The use of combustible vegetable waste in the manufacture of refractory insulating firebricks has a double advantage: making use of vegetable waste and decreasing the production cost of bricks.

Ground date seeds were added to kaolin and grog at different ratios and their blend was mixed with water. The wet mixtures were shaped in steel molds, dried overnight at 90 °C and fired at 1200 °C for 2 h. The physical and mechanical properties of the fired bricks were determined and found to be incompatible with standard values. Small amounts of polystyrene beads and perlite were then added to decrease the bulk density and increase the crushing strength. A mixture composed of 6% date seed, 72.5% kaolin, 17.5% grog, 2.5% perlite and 1.5% polystyrene produced bricks that abided by Indian Standards 2042 requirements regarding their bulk density, porosity, crushing strength, percent linear change on reheat and thermal conductivity at 600 °C.

Date seeds have been successfully used as pore generating material in the preparation of Class B insulating firebricks, in a mixture with kaolin, grog and small amounts of polystyrene and perlite.