Phosphoric acid purifying device

Abstract

The invention discloses a phosphoric acid purifying device which comprises an extraction device, a washing device and a back extraction device, wherein one single-stage extraction device consisting of a set of mixers and a phase-splitting device or one multi-stage extraction device consisting of a plurality of sets of mixers and a phase-splitting device is selected; one single-stage washing device consisting of a set of emulsifiers and a phase-splitting device or one multi-stage extraction device consisting of a plurality of sets of emulsifiers and a phase-splitting device is selected; and a continuous phase fluid inlet of the extraction device is connected with a light phase outlet of a last-stage phase-splitting device of the back extraction device, a single-stage solvent inlet of the washing device is connected with a light phase outlet of a last-stage phase-splitting device of the extraction device, and a single-stage solvent inlet of the back extraction device is connected with alight phase outlet of a last-stage phase-splitting device of the washing device. The invention has the advantages of strengthening the transfer property, improving the purifying efficiency, lowering the equipment investment and the operation cost, and having small occupation area.

Description

technical field [0001] The invention relates to the field of chemical equipment, in particular to a phosphoric acid purification device. Background technique [0002] Purification of phosphoric acid by solvent extraction is currently a commonly used process for purification of phosphoric acid. Solvent extraction generally includes extraction, washing, and back-extraction processes. At present, the chemical equipment that can realize the functions of extraction, washing and stripping are mainly as follows: Multi-stage mixing-settling tank is a typical step-by-step contact liquid-liquid mass transfer equipment, in which each stage includes two parts: mixer and settling tank, The main disadvantages of this kind of equipment are: the horizontally arranged multi-stage mixing-mixing tank occupies a large area, each stage is equipped with a stirring device, the flow of fluid between stages generally needs to be transported by pumps, and the equipment cost and operating cost are low...

AI Technical Summary

Problems solved by technology

At present, the chemical equipment that can realize the functions of extraction, washing and stripping are mainly as follows: Multi-stage mixing-settling tank is a typical step-by-step contact liquid-liquid mass transfer equipment, in which each stage includes two parts: mixer and settling tank, The main disadvantages of this kind of equipment are: the horizontally arranged multi-stage mixing-mixing tank occupies a large area, each stage is equipped with a stirring device, the flow of fluid between stages generally needs to be transported by pumps, and the equipment cost and operating cost are low. Larger; sieve tray tower, the light and heavy phases flow countercurrently in the tower, and the two phases are in cross-flow contact on each tray. The mass transfer efficiency of this tower is relatively high, but its internal structure is more complicated, and the production cost is higher. Internal cleaning is difficult; packed tower, packed tower structure is relatively simple, but the efficiency is low, can not be used for materials with solid particles and easy to scale; pulse packed tower and pulse sieve plate tower, in order to improve the contact between the two phases, strengthen mass transfer In the process, mechanical energy is added to the packed tower and sieve plate tower to cause pulsation, and the generation of pulsation is usually realized by reciprocating pump or compressed air. This type of equipment has high mass transfer efficiency, but the production cost is high, internal cleaning is difficult, and the operating cost Higher; vibrating sieve plate tower, the sieve plate in the vibrating sieve plate tower is fixed on a central shaft, driven by a crank linkage mechanism, the tower is limited by the material of the equipment, it is difficult to enlarge, and the operating cost is high

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