Study on pulping performance of a novel coal water slurry additive for Shenhua coal slurry with high concentration
Shenhua coal is difficult to form slurry of high concentration, low viscosity for its strong hydrophilicity. Based on that, coal water slurry (CWS) additive, denoted as LS-A, was used to prepare Shenhua coal blending slurry with high concentration, and then the slurry ability, rheological characteristic and static stability of LS-A were investigated. The results show that, the performances of CWS were improved by LS-A, and it had good viscosity reducing effect. The slurry concentration could reach 65.5%, and the apparent viscosity is smaller than 1200 MPa·s with good flow property under 100 s-1 of shearing rate when the dosage of LS-A was 0.7%. The rheological investigation indicated that the slurry pumped with LS-A is pseudoplastic fluid, and it had rheological property of shear-thinning, evident thixotropic property and good stability. Moreover, the comparison of pulping properties and stability between LS-A and the additive SPHF-3 of National CWS Center showed that, the slurry ability was similar under same additive dosage.
The effect of coal properties on the viscosity of coal–water slurries ☆
Abstract Studies on coal–water slurries (CWSs) have been conducted for many years to replace fuel oil. In this research project, the effect of coal properties on CWSs have been investigated using two Turkish coals of different ranks and a Siberian bituminous coal. Physical, chemical and surface properties of coal samples were determined. Furthermore, adsorption tests were carried out in order to put forward the effect of additive adsorption on the viscosity of CWSs. Viscosity measurements were realized for CWSs of various solid ratios by weight that were prepared using coal samples having mean particle sizes of 19, 35 and 50 μm.
Is the Benussi Effect a Kinetic Depth Effect?
Rapid, successive presentations of an eccentric circle pattern and its mirror-image elicited apparent depth and, as has been previously demonstrated for the Benussi effect, there was an increase in apparent depth with an increase in circle eccentricity. Taken together, these data were interpreted as contravening Wallach, Adams, and Weisz's account of the Benussi effect as an instance of the kinetic depth effect.