Delving into the heterocoagulation between coal and quartz at different shear rates by the focused beam reflectance measurement (FBRM) and particle vision and measurement (PVM) techniques

Abstract In the present work, two experimental systems based on in-situ focused beam reflectance measurement (FBRM) and particle vision and measurement (PVM) were developed to quantitatively investigate the heterocoagulation that occurs in a binary mineral mixture consisting of coal and quartz at different shear rates. The former was used to determine the heterocoagulation degree between quartz and coal particles, while the latter was employed to obtain visual information of coagulation behavior of quartz particles on a coal flat surface. The results of the FBRM system obtained at suspension pH varying from 3 to 9 showed that the heterocoagulation degree between quartz and coal particles increased over time. These results also showed that the heterocoagulation degree gradually decreased as the shear rate increased from 30 s−1 to 68 s−1 regardless of pH change. The results of the PVM system showed that the effect of agitation time on heterocoagulation between quartz particles and a coal flat surface was similar to that obtained between quartz and coal particles. However, the heterocoagulation between quartz particles and a coal surface was less severe than that between quartz and coal particles and was more sensitive to the change of shear rate.