Relationship between Rate Constants in Sedimentation of Coal Slurry in Water

摘要

It has been found that the sedimentation phenomenon is a rate governed process which is a combination of a constant rate followed by falling rate period It has earlier been observed that the rate of decrease of interfacial height with time is proportional to the difference between the height at any time and the equilibrium height, raised to the power 0.1. The proportionality constant is termed as the sedimentation rate constant. Considering the limit of the interfacial height as (i) initial and equilibrium height (overall condition), (ii) initial height and critical height (condition of constant rate period), (iii) critical height and equilibrium height (condition of falling rate period), the proportionality constant, are termed as overall rate constant, (K{sub}o); rate constant for constant rate period, (K{sub}c) and falling rate constant, (K{sub}f) respectively. Considering various particle sizes and slurry consistencies, it has been noticed that the magnitude of over-all rate constant can successfully be expressed as the arithmetic mean of the constant and falling rate constants.