SU457246A1 - Reactor for producing phosphoric acid - Google Patents

Description

one

The invention relates to the chemical industry and can be used in the production of phosphoric acid.

A phosphoric acid reactor is known that contains at least one cylindrical chamber with a lid, a propeller agitator centrally located inside it with a direct flow valve, a diffuser, and circumferential iperiferial agitators, each of which is equipped with turbines installed in several Russ.

However, the known reactor has a small specific evaporation surface, which excludes the possibility of increasing its performance due to overheating of the reaction mass.

The purpose of the invention is to intensify the process of heat removal of the reaction.

For this, the proposed reactor is equipped with a spraying device made in the form of a cone-shaped sleeve with a concave surface mounted on the drive shaft of each peripheral mixing device above its upper turbine, and nozzles for supplying cooling air to the spreading zone.

The spraying device is mounted on the shaft so that its lower part is buried in the pool and the top is located above it; cooling air inlets are mounted in the lid of the reactor chamber so that their lower ends are located between the zero mirror and the upper part of the dispersing device.

FIG. 1 shows the proposed reactor; in fig. 2 - peripheral non-mixing device.

The reactor contains two cylindrical chambers 1 and 2 interconnected by flow, in which peripheral mixing devices 3 and

central propeller mixer 4. Peripheral mixing devices 3 are made of Rus, of which the three lower ones are turbines 5-7 of open or closed type of different diameters. The diameter of the turbines decreases over the length of the shaft (i.e., the diameter of the turbines 5 is larger than the diameter of the bit turbines.) To ensure more efficient mixing, which contributes to a uniform cooling of the reaction mass.

Claims (1)

The upper level of the peripheral mixing devices is a spray device 8, made in the form of a cone-shaped sleeve with a concave surface, the lower end of which is recessed into the pulp, and the upper one is located above it. In the lid of the reactor chambers, the nozzles 9 for supplying the air flow are mounted, installed so that their lower ends are placed, between the mirror and the upper part of the spraying device. In addition, there are 10 air openings on the cover for air outlet. Chamber 2 is equipped with pumps 11 and choke 12. The reactor operates as follows. Sulfuric and circulating phosphoric acids are introduced into the peripheral part of the reactor, and phosphate raw materials using a central propeller stirrer 4 - the node of the reaction pulp layer. The reagents are evenly distributed over a short period of time using peripheral turbine mixing devices 3 but the entire cross section of the chamber 1, in which the process of raw material decomposition takes place. After decomposition, the pulp through the overflow enters the chamber 2, where the supersaturation of the liquid phase of the pulp in calcium sulfate is removed and the calcium sulfate crystallizes on the crystalline nodule formed in the first vessel, which excludes the formation of fine calcium sulfate crystals. The installation on peripheral mixing devices 3 of three lower russ — turbines 5–7 of open or closed type of different diameters — makes it possible to produce in the reactor volume, due to the different mixing intensity, the separation of particles by size along the height of the reactor, i.e. parts of the reactor and, thus, are longer in it than fine particles. The proposed reactor provides a higher specific heat removal from the pulp surface due to the development of a specific evaporation surface and additional heat removal due to water and air cooling of the metal shell of the reactor. In order to remove heat from the reaction volume and maintain the required temperature through the nozzles 9, which are installed so that their lower end is located between the working level of the pulp in the apparatus and the upper end of the sawing device 8, an air stream is fed through the nozzles 10 that are flush with the lid . During the operation of the reactor due to the installation on the peripheral mixing devices of the spraying device, the working pulp is aspirated and ejected in the form of droplets of the sprayed fan into the gas phase of the reactor. Entering the air flow through the nozzles 9 allows to increase the specific evaporation mirror in the reactor approximately three times, since the air flow passes through the channels of the sprayed fan are zero, and thus sharply intensify the heat removal from the reaction mass at a constant air flow and increase the removal of P2O5 from units of reaction volume. In addition, in the reactor, additional heat removal through its walls is provided by air or water cooling of the latter. Sometimes the spray device 8 may act as a defoamer. The destruction of nene resulting from the acidic shelter of carbonates occurs as a result of the blow of a circulating sprayed fan of nulpa on the surface of nene. The reactor removes calcium sulfate supersaturation and separates the largest calcium sulfate crystals in chamber 2, in which the peripheral non-mixing devices work, the reaction mass is evenly cooled, resulting in salting out of calcium sulfate from the solution due to a decrease in its solubility. At the same time, the coarse calcium sulphate fractions are separated into the lower pulp layer, from which the production pulp is withdrawn through the nozzle 12 to filtration. The upper layer is pulverized using circulation pumps. It returns to the stage of decomposition of phosphate into chamber 1. Claims of the invention A phosphoric acid reactor containing at least one cylindrical chamber with a lid, a propeller agitator centrally located inside it with a guide diffuser and placed around the circumference Peripheral non-mixing devices, each of which has turbines, are located in several ranks, characterized in that, in order to intensify the process of removing the heat of reaction, it is abzhen spattering device, designed as a conical sleeve with a concave surface, mounted on a drive shaft shake for each peripheral device over the upper turbine, and pipes for supplying the cooling air into the spray zone. Uroeny pulp YU