Showing papers by "Jyeshtharaj B. Joshi published in 1982"
TL;DR: In this paper, the hydrodynamic, heat and mass transfer characteristics of mechanically agitated contactors have been critically reviewed and the mixing time (θmix) can be correlated well by a model based on circulation path and average circulation velocity.
222 citations
43 citations
TL;DR: The effect of pH on the removal of pyritic sulfur in air/water chemical coal cleaning was investigated in this article, where the pH was varied by adding sulfuric acid or sodium carbonate to a coal-water slurry.
Abstract: The effect of pH on the removal of pyritic sulfur in air/water chemical coal cleaning was investigated. The pH was varied by adding sulfuric acid or sodium carbonate to a coal-water slurry. The effect of nearb neutral pH ( about7) was determined in a buffer solution of sodium dihydrogen phosphate and disodium hydrogen phosphate. Data were taken in the temperature range of 130 to 190/sup 0/C, oxygen partial pressure of 0.32 to 1.36 MPa, and reaction times up to 3600 s. The rate of pyrite oxidation was found to be minimum at the nearby neutral conditions. Under otherwise identical conditions, the rate of pyrite oxidation was greater in basic pH than in acidi pH. The enhancement in the rate of pyrite oxidation is explained on the basis of electrochemical reactions. Under nearly neutral conditions, the overall reaction is shown to be controlled by the surface reaction, whereas under acidic as well as basic conditions, diffusion of oxygen through the product ash layer as well as the surface chemical reaction seems to be important.
7 citations
TL;DR: In this article, the dynamic liquid hold-up, effective interfacial area, a, and the liquid side mass transfer coefficient k L a were determined for 0.1 m and 0.2 m multifilament wire gauze packings.
5 citations
01 Jan 1982
1 citations