SU1038308A1 - Apparatus for pelletizing slag close to blast furnace - Google Patents

Abstract

INSTALLATION OF THE EXTENDED GRANULATION OF SLAG, containing working and backup technological lines, each of which includes a rotor, a receiving hopper, a slag airlift chamber, a clarified water chamber connected to the slag airlift chamber through a weir, and a device for supplying clarified water to a hydrofluidor that differs that in order to prevent contaminated water from entering the water basin and to ensure the stability of the operating parameters of the installation, it is equipped with waste water with an air lift installed in it m connected with the receiving hoppers of both technological Li-, SRI, and the clarified water chambers are interconnected and mO sewage conduits disposed therein with switching valves. (L so oo so about 00

Description

The invention relates to ferrous metallurgy, in particular, to marginal slag granulation. A known plant for granulating and dewatering slag from a blast furnace, containing a hydronuclear tank, a receiving bunker with overflow devices communicating with an airlift with a carousel-type device for dewatering and drying granulated slag and a circulating water tank with pumps for supplying water into a hydrofluidor 1 . The disadvantages of this installation are the rapid deterioration of pumps pumping incompletely clarified circulating water, as well as partially discharging contaminated wastewater into the factory wastewater treatment plants, which leads to the gradual exorcism and cementation of external drainage routes and the need for their periodic cleaning. Closest to the proposed one, there is a well-known installation for the subdomain granulation of slag, containing a hydronucleator, a receiving bin connected in the lower part with an ashlift airlift chamber, which, in turn, is connected through an overflow to a clarified water chamber with an airlift installed in it for guduchi water in a hydrogranor and both a slaughter-type slag driver. In this plant, for pumping recycled water to the granulation, more reliable, durable and less demanding servicing was used in comparison with pumps, the airlift of the Domain furnace is supplied with four such autonomous installations (process lines), two for each side of the casting yard. At the same time, at each granulation unit, one line is in working condition, and the other is in reserve G2. However, this unit does not preclude the discharge of contaminated water from the working tanks into the sewage system or the external circulating cycle of the plant. The main contaminating components of water are: lightweight (floating) ass, hydrogen dissolved in water, alkalis. The discharge of polluted water from the installation takes place when repairs are carried out on it, when all its tanks are depleted from water (a receiving hopper, a slag airlift chamber, a clarified water chamber), as well as during the removal operation due to the overflow of the indicated tanks with water. In this case, the particles of lightweight slag periodically enter the external drainage channels through the overflow pipe, settle into them and cement over time. In addition, a disadvantage of the known installation is the fluctuation of the water level in the clarified water chamber, which causes significant changes in the flow rate of the circulating water supplied by the airlift to the hydro granulator, which impairs the granulation process. The fluctuation of the water level occurs due to the fact that at the time of the start of the airlift operation, water from the clarified water chamber in an amount of up to 80 goes to fill both the airlift itself and the pipelines connecting it to the hydraulic granulator. Lowering the water level reduces the airlift diving rate and, accordingly, the airlift capacity. After launching the airlift into operation to ensure its design performance, the water level is restored by supplying make-up water. However, at the end of the airlift operation, water from the separator tank of the airlift pipelines flows back into the clarified water chamber, as a result of which the water level in it rises above normal and the water flows into the external network of the plant through the overflow. Fluctuations of the water level in the secondary chamber occur during the operation of the granite due to the slag closing the window connecting the receiving hopper with the slag airlift chamber, which leads to the rupture of the working circuit of the circulating water supply. In this case, in order to maintain the level of water in the clarified chamber, it is necessary to additionally supply technical water to it. When pumping off the slag from the receiving bin, the connecting window of the bunker with the slag airlift chamber opens, and the excess water is discharged through the drainage channels to the factory water supply network. The purpose of the invention is to prevent the ingress of polluted water into the water basin and to ensure the stability of the operating parameters of the installation. This goal is achieved by the installation of slag granulation, containing working and backup production lines, each of which includes a hydronuclear generator, a receiving bin, a slag airlift chamber, a clarified water chamber, connected to the slag airlift through a spillway, and a feeder clarified water into a hydrogranor, equipped with waste water with an airlift installed in it, connected to the receiving bunkers of both production lines, and the chambers with clarified water are interconnected and with sewage, pipelines with key switches located in them. The drawing shows schematically the proposed installation (all positions of units and parts additionally have digital indices 1 or 2, depending on which production line they belong to; the positions of units and parts common for both technological lines do not have these indices).

The installation consists of two technological lines, on which one (any) is working, and the other is backup.

Each process line of the installation contains a slag channel 1, along which the hydrogranule 2 is located, the receiving hopper 3 adjoining it with a chimney 4.

In the lower part, the receiving bin 3 communicates through the window 5 with the chamber 6 of the slag airlift 7 connected at the top with a dehydrator 8, which is connected with the receiving bin 9 of its production line and the pipe 10 with the clarified water chamber 12 of the neighboring technological line.

The chamber 6 of the slag air lift 7 is connected through the spillway 11 to the chamber 12 of the clarified water, in which. an airlift 13 is installed to supply water to the pelletizer 2 (instead of an airlift, a pump can be used to receive polluted sewage, the plant is equipped with a plug 14, which has an airlift 15 connected via a separator 16 to trays 9 of both process lines through pipelines 17 on which valves are installed 18.

The chambers 12 of the clarified water of both process lines are interconnected and with a primer of 14 drain lines 19 and 20, a tee 21 with switching valves 22 and 23 embedded in them.

On trays 9, shut-off valves 24 are installed, and on pipelines 10 - shut-off valves 25,

The technological line, the nodes and parts of which are digitally numbered with the index 1, is working, and the rights, the nodes and details of which are, the index 2 is reserved.

The description of the plant operation is given in two operating modes: the first mode — the backup line is in good condition; the second mode — the backup line is in repair.

 In the first mode of operation, the position of the individual units and parts of both process lines is as follows: the dehydrator 8-1 is connected to the receiving bin 3-1 via tray 9-1 with the valve 24 open and disconnected from the clarified water chamber 12-2 using the valves 25-1; Dehydrator 8-2 is connected to chamber 12-1 of clarified water (valve 25-2 is open on the pipeline. 10-2) and disconnected from receiving bin 3-2 (valve 24-2 is closed on

tray 9-2); all the tanks of the lines of the lines receiving hoppers 3-1 and 3-2, chambers 6.-1 and 6-2 of slag airlifts, chambers 12-1 and 12-2 of clarified water are filled with water (chambers 12-1 and 12-2

clarified water communicates between -shock (valves 22-1 and 22-2 are open at conduits 19-1 and 19-2 J and are separated from wastewater 14 (valve 23 is closed at pipeline 20);

0 installed in model 14 airlift 15; does not work.

The installation of the granulation works as follows.

Molten slag from blast furnace

The furnaces along chute 1-1 are discharged into a stream of water coming out of hydrogranules 2-1, which are crushed into small pieces, after which the donkey particles fall into the receiving hopper 3-1 filled with circulating water. Formed

0 steam is discharged through the exhaust pipe 4-1 to the atmosphere. The slag particles that fall into the receiving bin 3-1 are finally cooled, settle, and through the window 5-1 in the lower part of the receiving bunker 3-1 enter the chamber 6-1 of the slag airlift 7-1.

Using slag airlift 7-1, slag slurry rises upward and then enters the dehydrator.

0 8-1, from which, after dewatering, granulated slag is removed by conveyors (not shown), and the filtered water in tray 9-1 is led back to the receiving bin 3-1. In the process of granulation

d slag circulating water from the receiving bin 3-1 through the window 5-1 or the upper overflow device (not shown) enters the chamber 6-1 of the slag airlift 7-1, and then through the overflow 11-1 it is poured into the chamber 12-1 clarified water, from which an airlift 13-1 water is supplied to a hydrogranular torus 2.

Simultaneously with the slag airlift 7-1, the slag airlift 7-2 of the backup line is operating, which supplies circulating water from chamber 6-2 to the dehydrator 8-2 and further along pipeline 10-2 the circulating water enters the chamber 12-1 of the clarified water of the working process line. ,

from which excess water through conduits 19-1 and 19-2 and tee 21 returns to the clarified water chamber of the backup line. At the same time, the water level in the backup process line is maintained 1 m below the working level. Maintaining the water level in the backup process line is done by supplying make-up water, the flow rate

0 which is equal to the costs of evaporation during granulation and moisture of the slag.

Thus, in the chamber 12-1 of the clarified water of the working process line, the constant working water level necessary for the operation of the airlift 13-1 with a given capacity is constantly maintained.

At the same time, the lightweight (floating) ass formed during granulation does not accumulate in the clarified water chamber 12-1, and along with the water moves along the drainage ducts 19-1 and 19-2 and the tee 21 into the clarified water chamber 12-1 airlift in which over time settles to the bottom. But since the slag airlift 7-2 and both of the eight 8-2 eeaters are working, the settled down slag on the bottom, chambers 6-2, is captured by the dehydrator 8-2.

At the end of the granulation process, the airlift 13-1 is turned off and the water contained in it returns to the clarified water chamber 12-1, and from it through the drainage channels 19-1 and 19-2 and the tee 21 flows into the clarified water chamber 12 of the backup process line . In this way, the discharge of contaminated circulating water into the external network of the plant is excluded.

In the second mode of operation, the position of the individual components and parts is as follows: the dehydrator 8-1 is connected to the receiving hopper 3-1 by means of the tray 9-1 with the clamp 24-1 open and disconnected from the chamber 12-2 of the clarified carrier through the valve 25-1; dehydrator 8-2, slag air-lift 7-2 are not involved in the operation) chamber 12-1 of clarified water is separated from chamber 12-1 (valve 22-2 is closed at drainage 19-2 / and communicates with actuator 14 (valve 23 is open the drainage system included the air-lift 15 installed in mark 14, with its supply to the receiving bin 3-1 via pipeline 17-1 (gate 18-1 is open, and 18-2 "closed) and tray 9-1.

The processes of granulation of the slag melt, the raising of the slag pulp with an airlift 7-1, the dehydration of a grangluc in a dehydrator 8-1 ,. The unloading of the self-hydrated slag from the degreaser 8-1 and the return of filtered water to the receiving bin 3-1 are performed in the same way as in the first mode.

Airlift 15 continuously supplies water from landmark 14 to chamber 12-1 of clarified water through separator 16, open valve 18-1, pipeline 17-1 and tray 9-1, ensuring a constant level in it (and accordingly

5, the operation of the airlift 13-1 with a given capacity), since the excess water through the outlets 19-1, 20 and the tee 21 returns to the additional capacity 14 when the valve 23 is open.

Thus, in the second mode of operation, the granulation unit prevents the discharge of contaminated circulating water into the external network of the plant and ensures a constant level

5 water in the clarified water chamber needed to supply a given amount of water to the granulation.

Thus, the use of the proposed installation will allow: to exclude the discharge of polluted water into the external open circuit of the water supply with outflow channels of great length and additional septic tanks, sewage treatment plant and two pumping stations; reduce to a minimum the flow of process water for feeding; maintain a constant water level in the working process line, which ensures the stability of the operating parameters of the granulation water; reduce equipment wear and, therefore, increase the turnaround time of the installation.

Claims (1)

INSTALLATION OF HOUSING SLAG GRANULATION, containing a working and reserve technological lines, each of which includes a hydro granulator, a receiving hopper, a slag airlift chamber, a clarified water chamber connected to a slag airlift chamber through a spillway, and a device for supplying clarified water to a hydrogranulator, distinguished by that, in order to prevent contaminated water from entering the water basin and to ensure stability of the operating parameters of the installation, it is equipped with a sewage pit with an airlift installed in it, Connections to the receiving hopper of both technological Li-. and the clarified water chambers are interconnected and the sewage sump by pipelines with switching valves located in them.