Study of Microstructural, Physical, Thermal, and Mechanical Properties of Organic Waste–Incorporated Fired Clay Bricks in the Framework of Energy Conservation

This comparative study investigated the microstructural, thermophysical, and mechanical properties of tea waste–, sawdust-, and wheat husk–incorporated clay bricks. The bricks were prepared by missing clay with different amounts of organic wastes and firing at 600°C and $\mathrm{1,000}°\mathrm{C}$. A transient plane source technique was used to measure the thermal properties of the fired bricks. The calorific values of the tested organic wastes were measured in the range of $15–17\mathrm{MJ}/\mathrm{kg}$. The maximum loss on ignition of tea waste–, sawdust-, and wheat husk–incorporated bricks was measured at about 14.94%, 13.75%, and 9.26%, respectively. The tea waste added–bricks exhibited the highest water absorbance, $20.8\%–35.7\%$, among all the tested samples. The specific surface area of the tea waste–, sawdust-, and wheat husk–added bricks was measured at about 146.43, 139.47, and $167.25{\mathrm{m}}^2/\mathrm{g}$, respectively. Similarly, the pore volume was measured at about 0.192, 0.184, and $0.219{\mathrm{cm}}^3/\mathrm{g}$, respectively. When compared with a reference brick, the compressive strength decreased by $15\%–59\%$ for $2\%–8\%$ by weight of tea waste, by $12\%–59\%$ for $2\%–10\%$ by weight of sawdust, and $31\%–69\%$ for $1\%–4\%$ by weight of wheat husk in the brick. However, the compressive strength of the waste-added bricks was still in good agreement with Pakistan building code standards.