SU1530239A1 - Reaction essel for producing phosphoric acid - Google Patents

Abstract

The invention relates to the design of equipment used in the field of production of phosphoric acid, and reduces the energy and operating costs in a reactor containing a housing with internal agitators and bulkheads with overflows, one of which is in a vertical shaft with upper and lower windows placed the stirrer-circulator, the lattice of the failure type, to which the reaction slurry is fed, nozzles for introducing gas and initial reagents, nozzles, and devices for withdrawing reaction products, wire On one side, a plate is installed in the upper flow of the partition wall in front of the circulator; on the other side of the partition, the Koroboobrazny vertical wall is buried below the slurry level, and the gas inlet fitting is placed on opposite sides of the grid, and its side walls are not adjacent to the grid are performed below the pulp level. 1 hp f-ly, 2 ill.

Description

The invention relates to the design of reactors for producing phosphoric acid.

The aim of the invention is to reduce energy and operating costs.

Fig. 1 schematically shows a reactor for producing phosphoric acid, a cross-section; figure 2 - reactor without cover, the plan.

The reactor consists of a housing 1, which, for example, may consist of two overflow tanks. From above, the reactor has a crinkle 2. Mixers 3 are spaced apart evenly inside the reactor. Inside the reactor there are partition walls 4 with overflows. A circulator 8 is mounted in one of the partitions in the vertical shaft 5 with the top 6 and bottom 7 windows. In the upper overflow 9 of the partition in the section in front of the stirrer, a grating 10 is installed on one side of the partitioner on the other side of the partition and a vertical wall 11 buried below the pulp level of the spike. A branch pipe 12 for introducing gas under the grille psmc1.1 is from the opposite () H lattice 10, and

its side walls 13, which are not adjacent to the grid, are lower than the pulp level. A nozzle 14 for introducing sulfuric acid is placed in the lid of the reactor opposite the exit of the pulp from the circulating mixer, as well as in the ripening zone. Pipes for introducing phosphate and dilution solution 15, as well as for discharging gas 16, are also located in the reactor lid of the decomposition zone,

In the flow between the first (decomposition zone) and the second (ripening zone) capacitors of the housing 1, a lattice 17 of the failing type is placed, filled in another embodiment — not with gas blowing, but with its suction. In this case, the nozzle 18 for gas outlet is placed above the grid, with its side walls adjacent on three sides to the grid and to the box-shaped vertical wall, and the nozzles 19 for supplying gas under the reactor lid are located on the opposite side of the reactor (maturing zone). It is advisable between the pipe 18 and the grid 17 to place the separation zone 20.

It is advisable for the purpose of a more equal, number distribution on the failure grating of cooled pulp and gas to make it inclined in the direction opposite to the box-shaped vertical wall.

The reactor can be equipped both with one collapsed lattice of lattice type 10 (with gas blowing), and only with lattice of lattice type 17 (with gas suction), as well as in combinations of both types, as shown in FIGS. 1 and 2, for A number of cases are more preferable. Hatches 21 can be provided for servicing the failure gratings. Devices (pumps) 22 are installed to output the production slurry to filtration. Partition 4 in the decomposition zone makes it possible to carry out directional recirculation of the slurry with a given multiplicity, and in the ripening zone create a mode close to the following - body displacement of the pulp from the beginning to the end of the zone, which is optimal for carrying out the process of obtaining EPA.

It is advisable to perform the ripening zone of the reactor below the decomposition zone, which will allow maintaining a constant mode of operation of both the failing grids and the agitators of the decomposition zone.

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The reactor operates as follows.

Source reagents (phosphate, dilution solution and sulfuric acid) are fed through patrols 14 and 15 into the decomposition zone inside the housing 1. At the same time, the stirrers 3 ensure their quick and uniform mixing in the reaction slurry. The stirrer-circulator 8, rotating in the shaft 5, operates as an axial pump, pumping pulp entering through window 6 and leaving through window 7 through the entire reaction volume of the decomposition zone bounded by partitions 4 with overflows. At that, a part of the pulp can circulate, a dummy lattice 10 flows through the upper septum overflow, and another part of the pulp falls onto the lattice 10. When pumping the pulp, the circulator agitator creates a level difference in the reactor sections equal to its head. This allows gas (or air) to be introduced under the grill 10 through the pipe 12, delimited by walls 13. Thus, intense heat and mass transfer occurs between the reaction slurry and the gas supplied to cool it. The exhausted gas (saturated with water vapor) is brought down — under the crushing of the reactor 2 and inlet 16, while separating it from the pulp splashes due to hitting the pulp mirror and loss of velocity in the gas volume. The vertical wall 11 allows the pulp to fall freely from below to flow 9 and further to the lattice Yu, simultaneously blocking the passage of the blown gas there, which is necessary for normal operation of the lattice. Such a flue gas under the grate — first a blow to the pulp mirror, and then a passage through the curtain of falling jets and then under the grate — is more favorable in terms of reducing the fouling of the grate, since in this case the gas is preheated by hot pulp and the temperature gradient between them on the grid decreases.

The circulator mixer allows two functions: the nyhbmj circulator inside the reactor and the pulp circulator in the cooler — a diving type lattice. This is made possible by the proposed technical solution. In this case, the fail-type grating in a number of cases is advisable to be performed with gas suction. Togdz

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pulp, for example, downstream of the reactor decomposition zone into the zone of ripening, the passage through such a grate 17, under which the free gas volume of the dosing zone is located, is additionally cooled by gas (air) sucked under the reactor lid through nozzles 19 and various leakages in lid 2. Pulp It also enters the grate 17 from below through the curved wall, then through the overflow. In a number of cases, gas can be sucked under the grate 17 both from the decomposition zone and from the ripening zone. The exhaust gas, the passage of the separation zone 20, is separated from the spray and discharged through the pipe 18 to the absorption.

For mounting and dismounting grates, cleaning them during operation, repair, inspection, and so on, hatches 21 serve.

Chilled pulp

1. A reactor for producing phosphoric acid, comprising a housing within which partitions are placed, forming sections with mixing devices located in them, and in one of the partitions having upper and lower flows, a circulator stirrer, a wire grate and inlets for inlet are installed gas and initial reagents and removal of reaction products, characterized in that, in order to reduce energy and operating costs, the partition wall is provided with a box-shaped wall installed on one side, recessed the pulp layer, and a failure lattice ustanovLe-

mature section of the ripening zone

the reactor, enters the last section, 25 on the opposite side, in a patruot from where, for example, by a 22-sided pump to inject gas, which is made

with on the filter. in terms of a 3-section, envelopes The proposed technical solution is a broken grating, while

allows by excluding the speci-side walls of it, not adjacent

equipment for pulp feeding on the 30 grate are located below the level

Oj per day excludes one pump type TXL-500/20 of 110 kW each with a service life of 1-4 months.

Claims (2)

1. A reactor for producing phosphoric acid, comprising a housing within which partitions are placed, forming sections with mixing devices located in them, and in one of the partitions having upper and lower flows, a circulator stirrer, a wire grate and inlets for inlet are installed gas and initial reagents and removal of reaction products, characterized in that, in order to reduce energy and operating costs, the partition wall is provided with a box-shaped wall installed on one side, recessed the pulp layer, and a failure lattice ustanovLe- lattice and lattice thermostats reduce energy and operating costs. For example, for a reactor with a working volume of 900 m - systems for the production of EPA with a capacity of 365 tons pulp. 2. Pop-1 reactor, characterized in that the failure grating is installed with a slope opposite to the box-like wall. Si t r tr t