Recycling of washed olive pomace ash for fired clay brick manufacturing

Milled or micronized washed olive pomace ash was used to replace different amounts (5 and 10 wt%) of clay in brick manufacture. The properties of these bricks were compared to conventional products following standard procedures. Bricks formed with ash showed a decrease of 0.13-0.16 W/m K in thermal conductivity. With a minimum bulk density and bending strength of 1790-1810 kg m(-3), and 10-12 N mm(-2), respectively, fired bricks fulfil standard requirements for clay masonry units. Milled ash performs better than micronized ash. The ash leachate is a valuable source of potassium for the manufacture of fertilizers. (C) 2014 Elsevier Ltd. All rights reserved.