Effect of concentration, size, granularity, shear time and temperature on rhological properties of coal water slurries

Abstract

Coal water slurries (CWS) were proposed as a substitute for the fuel oils century ago. As there is a huge demand for energy, it is necessary for us to use such concepts with good understanding of the alternative fuels. As the use of CWS depends on physio-chemical properties of coal and rheological properties of the slurry, coal obtained from Dugda coal washery, Jharkand, India were subjected to examination. These coals are ground and segregated according to the sizes and the samples of CWS were prepared. The prepared samples were tested for their physio-chemical properties first. various samples of coal water slurries were prepared and examined for rheology of the samples by varying their concentration, size and granularity of the particles, shearing time and temperature. A detailed analysis on stress strain relation was analyzed during this study. It is found that the stresses would increase with concentration of CWS when the strain rates are varied. It is found that the size of the particles would play active role in deciding the shear forces when the samples were subjected to varying shear rates with their self assembly. The granularity of the particles in the sample has significant effect in rheological properties of the CWS samples. The temperature has no effect.

Study on the Pressure–Sinkage Process and Constitutive Model of Deep-Sea Sediment

“…The yield stress is related to factors such as volume concentration, particle size, and clay properties. Among these, the volume concentration has the greatest influence, exhibiting an exponential relationship with the yield stress [36]. Therefore, the yield stress (τ) of deep-sea sediment can be expressed as Equation ( 4):…”