Improving the rheological characteristics of fly ash water slurry using aqueous extract of Diascorea hispida

Abstract

ABSTRACT Transportation of high-concentration slurry is a specialized field that requires a deep understanding of the rheological behavior of slurry. Fly ash, a fine, powdery residue of pulverized coal combustion in power plants, is transported in pipelines as a slurry with water as a carrier medium and flow-improver additives. The current research aims to compute the rheological properties of the fly ash-water slurry by adding 0.1 to 1 g/mL of Diascorea hispida extract as a natural drag reducer or flow improver. In addition to the effect of D. hispida, other parameters such as temperature, addition of fly ash, and fly ash-bottom ash mixture on the rheological performance of fly ash-water slurry have been investigated. The economic effect of the developed dispersant, D. hispida, has been examined by applying Darby – Melson combined equation by varying the slurry flow rate from 1 m/s to 3 m/s at a fixed 250 mm pipe diameter. The slurry head loss, solids conveying rate, hydraulic power need, and specific power consumption at different .D hispida concentrations were calculated.