Technical modification of alkali leaching circuit to improve slurry throughput into the autoclave

Abstract

Tummalapalle Mill represents an alkali leaching-based uranium processing plant. Alkali leaching occurs inside pressurized autoclaves at controlled temperature and pressure. Although the rated capacity of the Tummalapalle Mill is 3000TPD [1], few obstructions were present to achieve the rated capacity. The technical study was done by the process and mechanical engineer team of Tummalapalle Mill for necessary improvements to achieve the rated capacity, which helped in the overall grinding rate of the processing plant. In the alkali leaching section of the Tummalapalle unit, Autoclaves (pressure vessels) are used for alkali leaching purposes. To run the plant at full rated throughput, i.e. 3000TPD, it is required to push the slurry into autoclaves by double hose-diaphragm pumps through spiral heat exchangers with a sufficient flow rate. During the regular course of operation, each double hose-diaphragm pump was able to discharge a limited flow rate with the existing motor-designed parameters. This paper deals with the technical details of double hose-diaphragm pumps, recent technical modifications incorporated & consequent trials taken to increase the pump flow rate and thereby achieve the required throughput into autoclaves.