Method and system for recovering elemental phosphorus by dry cooling of phosphorus-containing gas

Abstract

The invention discloses a method and system for recovering elemental phosphorus by dry cooling of phosphorus-containing gas. The method comprises the steps of pressurizing the dedusted phosphorus-containing gas, carrying out vortex cooling to obtain cold gas flow and hot gas flow, rapidly condensing gaseous elemental phosphorus in the obtained cold gas flow into solid particles, recovering the solid particles, and returning the obtained hot gas flow to the phosphorus-containing gas to be treated after heat exchange and cooling, and repeating the steps. The invention also discloses a system for recovering elemental phosphorus by dry cooling of the phosphorus-containing gas. The system comprises a gas pressurization system, a vortex tube, a heat exchanger, a rectifier and a gas-solid separator. According to the invention, phosphorus is collected by adopting a dry method, and the recovery efficiency of elemental phosphorus is effectively improved through vortex cooling; and no waste water or waste liquid is generated in the treatment process, and the method and the system are environmentally friendly, economical, high in treatment speed and suitable for large-scale application.

Description

technical field [0001] The invention belongs to the technical field of non-ferrous metal smelting, and in particular relates to a method and a system for recovering simple phosphorus by dry cooling of phosphorus-containing gas. Background technique [0002] At present, the industrialized production of yellow phosphorus generally adopts the electric furnace method to produce phosphorus. The production of yellow phosphorus by the electric furnace method is to add the mixed charge of phosphate ore, silica and coke into the electric furnace in a certain proportion, reduce the phosphate ore, and sublimate the phosphorus in it. The phosphorus-containing furnace gas is dedusted and condensed to obtain phosphorus products. The tail gas can be As a raw material for fuel and downstream chemical products. However, at this stage, both the collection of phosphorus furnace gas in the process of phosphorus production and the recovery of phosphorus in the yellow phosphorus tail gas mostly ...

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Problems solved by technology

[0003] For example, a multi-stage condensation scrubber can be used to collect phosphorus furnace gas. Not only is the equipment complex, but the water consumption is large, and the recovery efficiency is low. After washing and cooling, the washing water has been polluted by yellow phosphorus and dust, which will generate a large amount of waste water and cause excessive circulating water. It cannot be discharged, so this method is not advisable

As for the treatment of yellow phosphorus tail gas, the Chinese patent (CN 109911871A) discloses a method for the separation of elemental phosphorus in phosphorus-containing tail gas with temperature change and phase change. The dry method is used to recover the available elemental phosphorus, and the separation efficiency is high. However, it uses liquid dry ice and / or or liquid nitrogen to cool down, and the temperature needs to be raised before the treatment, which increases the energy consumption of the treatment invisibly, and this method also uses spray treatment, and the coolant injection tube group of the dry quenching tower is used to spray the coolant. In this way, simple phosphorus is cooled by gas-liquid mass transfer, the cost of coolant is high and subsequent recovery and reuse are difficult

Chinese patent (CN111256493 A) discloses a water film cooling method and device for recovering traces of yellow phosphorus in yellow phosphorus tail gas. The yellow phosphorus tail gas transfers heat to cooling water through heat exchange tubes, so that the temperature of yellow phosphorus tail gas reaches the required temperature. , although this method solves the problem of a large amount of waste water, due to the problem of heat transfer rate, the tail gas must fully exchange heat in the device to lower the temperature, so the residence time is long and the processing speed is slow, which is not suitable for large-scale applications.

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