Polyphosphoric acid production method using device for making acid from phosphorous slurry

Abstract

The invention provides a polyphosphoric acid production method using a device for making an acid from phosphorous slurry. The polyphosphoric acid production method using the device for making an acid from phosphorous slurry includes the steps: adding a phosphorous slurry byproduct from yellow phosphorous production to a phosphorous slurry groove, heating the phosphorous slurry to 70-80 DEG C, stirring and mixing the phosphorous slurry uniformly, and pumping the uniformly stirred and mixed phosphorous slurry into a nozzle in a combustion tower; atomizing the phosphorous slurry by compressed air, oxidizing the atomized phosphorous slurry with excessive 2.0 to 2.5 times of combustion-supporting air in the combustion tower to generate phosphorous slurry high temperature combustion gas containing P2O5 and water vapor, controlling the temperature at 1100-1200 DEG C, sending the phosphorous slurry high temperature combustion gas into a lower part of a hydration tower, and conducting a hydration reaction on the phosphorous slurry high temperature combustion gas and circularly sprayed phosphoric acid in a counter-flow manner, wherein the temperature of the circularly sprayed phosphoric acid is controlled at 80-100 DEG C, and heights of a circulating phosphoric acid liquid level and a phosphorous slurry high temperature combustion gas inlet tube are controlled to 400-600 millimeters; and controlling tail gas temperature at 90 DEG C or below, and directly discharging the phosphoric acid with the concentration in percentage by weight of 95%-105% from a circulating acid tube. According to the polyphosphoric acid production method using the device for making an acid from phosphorous slurry, the existing process and equipment for making an acid from phosphorous slurry are fully used for producing polyphosphoric acid; a lot of equipment investments are saved; the technological process is simplified; the energy consumption is reduced; and the method is especially suitable for the optimization and efficient utilization of the existing device for making an acid from phosphorous slurry, so that products produced by the existing device are increased dramatically in value, the scope of market application is wide, and economic benefits are significant.

Description

technical field

[0001] The invention relates to a new method for producing polyphosphoric acid using a mud phosphorus acid production device.

[0002] technical background

[0003] When the phosphorus chemical industry produces industrial yellow phosphorus, it will produce about 10% of mud phosphorus (main components are P4: 40-50%, H2O: 40-50%, solid impurities: 6-10%), mud phosphorus It is a kind of dangerous solid waste. The safe and environmentally friendly treatment method in the prior art is a mud phosphorus acid production device imported from Russia in Yunnan, which is specially used to consume the by-product mud phosphorus in the production of yellow phosphorus (the device It belongs to the environmental protection facility that must be operated synchronously with the main device of yellow phosphorus production), which sends the by-product mud phosphorus in the yellow phosphorus production into the mud phosphorus tank and heats it to 70-80°C, stirs and mixes evenly, ...

Images