Effect of agricultural biomass wastes on thermal insulation and self-cleaning of fired bricks

Abstract

This research investigates the feasibility of using dry crushed pomegranate peel waste as thermal insulator to produce light clay bricks. Pomegranate peel waste (PW) is used with different substitution levels of 0%, 5%, 7.5%, 10% and 15% of clay weight. The clay bricks were heated at temperatures of 700, 800, and 900 °C, that resulted in the formation of internal pores due to the combustion of PW. The bulk density, water absorption, porosity, shrinkage, and compressive strength are examined to evaluate the effect of using PW on the physical and mechanical properties of thermal insulation bricks. Also, the investigation of the effect of photocatalytic activity of bricks under sunlight irradiation is carried out. The use of PW increased the thermal conductivity up to 21% at 900 °C, water absorption from 22.6% in cold water to 29.1% in boiling water, density from 2.5% at 800 °C to 7.6% at 900 °C, and shrinkage from 4.3% in linear drying shrinkage to 5.4% in linear firing shrinkage. The heated brick samples at 700 °C showed greater photodegradation efficiency than firing clay at 800 °C and 900 °C. Moreover, the compressive strength decreased with the increase in replacement rate, reaching up to 74% for 15 wt% PW. This study confirms that lightweight heated bricks with low thermal conductivity and a reasonable compressive strength can be made using PW as a pore-forming agent.

Keywords

• Pomegranate peels
• Photocatalytic activity
• Compressive strength
• Thermal conductivity
• Shrinkage