Graphite bubble-cap tower for purifying wet-process phosphoric acid by solvent extraction method

Abstract

The graphite bubble-cap tower comprises a graphite tower body, multiple layers of tower plates are horizontally arranged in the graphite tower body from top to bottom, a downcomer is movably and vertically arranged on the edge of each layer of tower plate in a penetrating mode, and a distance exists between the top end of each downcomer and the surface of the corresponding tower plate; a upper downcomer and a lower downcomer are arranged on the left side and the right side of a upper-layer tower plate and a lower-layer tower plate in a staggered mode, the edges of the left side and the right side in the graphite tower body are each provided with a connecting shaft, the top ends of the connecting shafts extend out of the top of the graphite tower body, and racks are arranged at the extending ends of the connecting shafts and meshed with gears which are connected with servo motors. The connecting shafts extend downwards to penetrate into the downcomers on the same side and are fixedly connected with the downcomers, a lower overflow weir is arranged on the side, close to the downcomers on the upper portion, of each layer of tower plate, and the lower overflow weirs are connected withthe adjacent connecting shafts through lower overflow weir opening devices. According to the equipment, the functions of tower plate pollution discharge, emptying and automatic cleaning are achieved in a non-stop state, and it can be guaranteed that the bubble-cap tower operates without stopping throughout the year.

Description

technical field [0001] The invention relates to a graphite bubble tower used for purifying wet-process phosphoric acid by a solvent extraction method, and belongs to the technical field of chemical equipment. Background technique [0002] Wet-process phosphoric acid is less expensive to produce, but has higher levels of impurities, so it needs to be purified. Purification of wet-process phosphoric acid includes two aspects: (1) removal of sludge generated in wet-process phosphoric acid; (2) removal of dissolved phosphoric acid: fluorine, sulfate, iron, aluminum, magnesium, silicon, calcium, arsenic , lead, cadmium, etc. The purification process of wet process phosphoric acid includes: organic solvent extraction method, chemical precipitation method, ion exchange method, physical adsorption method and crystallization method. Among them, the solvent extraction method is relatively advanced, especially represented by Albright&Wilson Company, which uses MIBK as the extraction ...

AI Technical Summary

Problems solved by technology

The traditional graphite bubble cap tower has poor structural strength, high production energy consumption and low production efficiency

Due to the steady flow effect of the overflow weir on the graphite tray, solid impurities and sludge are deposited on the tray. After a period of time, the sediment blocks the bubble cap, resulting in the failure of the bubble cap column to work normally.

On average, the tower needs to be stopped and dismantled for manual cleaning once every two months, which not only destroys the stability of the process operation, but also increases the cost of operation and maintenance. It is very easy to cause damage to the graphite tower when starting and stopping, and also increases production costs and safety risks.

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