DE2122317B2 - Evaporative cooling system for metallurgical furnaces, especially blast furnaces - Google Patents

Description

55

The invention relates to an evaporative cooling system for metallurgical furnaces, in particular blast furnaces, which has a large number of cooling boxes, several of which via downpipes and risers are connected to an evaporation vessel and together with this form a subsystem.

Such evaporative cooling systems usually consist of disk-shaped ring systems several evaporation tanks, each evaporation tank being assigned a separate subsystem is. The individual evaporation tanks are on the water side through a water ring line and on the steam side communicating connected by an exhaust steam ring line. Instead of individual evaporation containers For each subsystem, a ring drum can also be used for each cooling disk to simplify matters half filled with steam and half with water.

In such evaporative cooling systems, the heat absorption of the individual subsystems is often different large, since different amounts of heat in the cooling zones assigned to the subsystems attack. This is e.g. B. particularly pronounced in blast furnaces. The pipe system of each subsystem must Be dimensioned so that the greatest possible amount of heat can be safely dissipated. It is overdimensioned for the amount of heat that normally occurs. Because of the ensuing low throttling effect of the pipe system, the subsystems tend to evaporate so strongly that erne cooling of the cooling water below the boiling point occurs and the evaporation stops. The normally natural cycle of the cooling water then stagnates in the relevant one Subsystem, until the still cooling water is heated to the boiling point again. After the cycle has started again, it can become hypothermic again in the manner described of the cooling water come below the boiling point, etc. The evaporative cooling system is tending So to pulsations of individual subsystems, which if several subsystems or the entire cooling disk pulsing synchronously, taking on uncomfortable proportions.

It is the object of the invention to create an evaporative cooling system of the type mentioned at the beginning, in which the occurrence of the pulsations described above is avoided, without the need for a greater structural effort is required than with the known evaporation aggregation systems.

The invention relates to an evaporative cooling system for metallurgical furnaces, in particular Blast furnace, which has a large number of cooling boxes, of which several over case and Risers are connected to an evaporation vessel and together with this form a subsystem, wherein the evaporative cooling system is characterized in that the risers of all subsystems in the area of the exit from the subsystems can be connected to one another by a ring line are, with the ring line facing the atmosphere, a pressurized gas connection and an emergency water drain is lockable. Such a ring main has a stabilizing effect on the entire circuit of the Evaporative cooling system.

Let it be B. assumed that in some of the subsystems the circuit due to subcooling of the cooling water stagnates below the boiling point, while in other subsystems a strong evaporation of the Cooling water takes place. Due to the rising in the risers of the heavily steaming subsystems Steam is generated in the ring line at a pressure that is lower than the pressure in the fall lines the subcooled subsystems at the level of the ring main. This will use the associated Risers exerted a suction effect on the subcooled subsystems, causing their circulation again is set in motion. The subcooled cooling water sucked in is transferred to the Part of the risers of the heavily evaporating subsystems are fed, causing a cooling there

3 4

and thus a reduction in the ascent rate of the emergency water supply and discharge ring speed the steam enters. The Hingen ring line is not required for this, as im has an all-round effect during the process thus accelerating the cycle of the unlikely short-term emergency water operation ring conductor cooled Subsystems and braking on the development and further ring main easily from the Cycle of heavily steaming subsystems. 5 parts still in the evaporation mode the stabilization of the natural stone will be able to be separated. Cycle of the evaporative cooling system reached. The further ring line can also be used as a

The ring line of the Veidarap mud line according to the invention can be used. To do this, the whifling cooling system does not provide a structural overhead ring main with a lockable blow-down wall because in the area of the exit of the sleigleio leave on. A separate blowdown ring line, Depended on the subsystems in general anyway where there is a risk of freezing in winter, a ring line is available, e.g. for discharge is not required with this arrangement, of emergency water for the emergency cooling of individual parts of the system. The connection between risers and

Stars. Ring line is preferably designed so that in

A preferred development of the invention 15 switched on the risers each with a three-way valve is characterized by the fact that the drop lines are whose third connection to the ring line veraüe; Subsystems in the area of entry into the sub-groups is. In this way, all Verbinsysteine through another ring line, connection options between the subsystems can be connected to one another are, the further ring line geeren risers and the ring line by a single over the atmosphere, a blowdown outlet 20 umpteen final control element established '-', and an emergency water supply can be shut off. It is known that parallel to the individual cooling cases

The lower ring line contributes to an additional stabilization of bypass lines with which unrurg of the natural cooling water cycle. You bridged tight cooling boxes if necessary namely ensures that the cooling water can be supplied evenly. The bypass lines are over drove to all subsystems, even if from the one 25 three-way cocks with the inlets and outlets of the Individual drop lines connected different cooling water men- cooling boxes. When using such can be delivered. This can e.g. B. in case of clogging bypass lines at the subject of the Erfineinzelner Fall lines will be the case. The widening is also according to a further development of the invention tere ring main does not provide any additional construction, that instead of the respective riser with wall, there in the area of the entrance of the FJ1-Lci- 30 the ring line connecting three-way cock lines in the subsystems is generally provided anyway four-way valve, the fourth to ring lines are available, e.g. an emergency connection with one directly connected to the riser water supply line or a drainage collecting ring-connected cooling box bridging bypass, line is connected. That way you can

The risers and / or the 35 one three-way valve per riser are preferably saved who-drop lines individually or for a subsystem.

mean from the ring line or from the other The individual subsystems can be connected with

Ring line can be separated by locking devices. Thereby sen be provided for pressure gauges, whereby the anist it is possible to use the individual subsystems e.g. to draw conclusions between the subsystems and the Emergency cooling, to be separated from the other subsystems 40 subsystems with the ring line or the other nen. It is also possible to have locking devices connecting the ring line and the ring line. on the further ring line for certain operating cases this way can be done in a manner known per se Individual sub-systems are only available for leak testing of the 1 express systems ! en. are, for security reasons, after closing

The ring main can only achieve a lockable pressure +5 Ben of the locking devices in the sub-systems themselves have gas connection. In this way, a pressure test, e.g. B. with previously supplied emergency cells Subsystems for the suppression of the boiling point water is made.

tes of the cooling water in them with pressure An embodiment of the invention is in the fol-

beau ^f can be struck and in this way described in per se on the basis of the drawing. In the known way leaks in the evaporation 50 drawing can be localized with 1 an evaporation ring drum cooling system. Designated via the ring line of a cooling disk, which can draw the pressure gas to any desired subsystem 8 and lead riser lines 15 to the cooling box 14 via the fall duct, without an additional line connection being made for this purpose. Twenty-four cooling units would be necessary each time. Most 14 are combined into a subsystem.

The ring line expediently has one or more 55 Two such subsystems are shown in the drawing Safety pressure relief valves open. This transferred. The expression valves lead to each subsystem are, for example, in the mentioned sub-steam ring drum 1 a fall line 8, which is in a Pressurization of sub-systems for each sub-system distribution line 9 opens and takes effect before the Einmün. As a result, the separate arrangement is made with a fall-line shut-off device 20 vervon - for security reasons several - is sure to see 60. There are eight cooling pressure relief valves on the distributor line 9 in each individual sub-sytem rr.it three consecutive stars are superfluous. Cooling box 14 connected. The cold chains are

The ring main has a shut-off emergency through cold chain shut-off devices 13 from the verser outlet and the further ring line has fire line 9 separable. Leads from every cold chain a lockable emergency water inlet. Each 65 has its own riser 15 back to the evaporation subsystem can be used in this way for emergency cooling on ring drum 1.

the emergency water supply to be connected The evaporation ring drum 1 is in usual

and be traversed by emergency water. Can be connected separately to a feedwater line7

5 6

and with a steam dome 2. a control bottle 3 The upper ring line 16 causes cooling and an overflow 17 to be provided. Chains that are caused, for example, by undercooling under the you-On the underside of the cooling disk, there is insufficient steam development on a lower ring line 10. Connection lines 11 with the individual connections 5 Other, more intensely steaming cold chains can arise due to the steam rise in the risers 15 oil connections 9 of the subsystems. The lower ring line 10 can be connected to an emergency water inlet 6 of the riser of the low-steaming cold chain or to a blow-off outlet 5 via cntspre- namely in the upper ring line 16 and thus into urgent shut-off devices. Pressure, which is lower than the pressure in the case. At the top of the cooling section there is line 8 of the low-steaming cooling chain at the level of an upper ring line 16, which has a three-way upper ring line 16 all risers 15 in connection with lalion in the low-steaming cold chain. The upper ring line 16 is supported by a corresponding support. At the same time, the risers 15 of the chcndc Abspcrrorganc can be connected to an emergency water connection 18 with strongly steaming cold chains water from the little or one compressed air connection 4. Further- 15 steamed cold chain supplied. As a result, the upper ring line 16 with one or from these risers 15 is the steam ascent is stopped - safety reasons with several safety over-brakes,
give away pressure valves 19. Overall, the natural cycle of the

Provided that, for fluidic reasons, the cooling water is uniform and stabilized.

can be stepped on, the eight individual risers 20 can be used for emergency cooling of a single

15 each subsystem is replaced by a riser.

will. in which all eight connection lines 11 are shut off via a collecting line, with the exception of

Merge cold chains. In this case, the person who is to be operated with emergency water is per part of the system

star only a three-way valve is assigned to connect this part of systc.vi. Furthermore, the

individual riser with the upper ring main 16 25 three-way cocks 12. which can be operated with emergency water

required. are assigned to the subsystem so that

To cool boxes 14 that have become leaky except loading the cooling chains of this subsystem with the above

To set the drive, bypass lines 24 can be used for ring lines. but not with their risers

each cooling box 14 can be provided. Possible are connected. All other three-way cocks 12 are

Reversing lines 24 are drawn in the drawing in such a way that the associated cold chains are indeed

chclt indicated. The bypass lines 24 with their risers 15 are not but with the above

are normally connected to the supply ring line 16 via three-way cocks 23. Emergency water supply

and discharge of the respective cooling box 14, connection 6 and emergency water drain 18 are opened, while

the. In the outlets of the top cooling box rcnd compressed air connection 4 and insulation outlet 5

rcihc. namely the risers 15 is so far 35 remain closed. In this case as a coolant

a simplification possible, as there the serving emergency water then flows through the emergency water

Drciwcgchähne 12 provided for connection to the upper cooling subsystem and cools this

Ring line 16 are present. These can through ab. Since the rest of the sub-systems come from the upper ring

Vicrwcgehähne 22 are replaced, not only to the line 16 and the lower ring line 10 separated

the connections to the upper ring line 16 but 40 are, the stabilizing effect of these ring lines falls

the upper bypass lines 24 were also connected. However, this is not disadvantageous,

can be sen. In this way, only one cooling system can be used for emergency water operation in a subsystem

chain a three-way valve 23 can be saved. represents an exceptional operating state.

With the help of the lower ring line 10 and the upper In the leak test with compressed air, the three ring line 16 and the associated shut-off cocks 12 of the subsystem to be tested are four different modes of operation of the cooling! .Share that this with the upper Ring line 16 is not a disk of the evaporation cooling according to the invention but is connected to its risers 15. The systems possible, namely normal operation, emergency water operation associated with the subsystem to be tested, leak testing with compressed air and blowdown shut-off devices 13 are closed. All the rest. 50 gen cold chain shut-off devices 13 and also are running normal operation interconnections Case Leitungsabsperrorgane 20 can remain open while Notv.asserzu · chain-shut-off devices 13 are opened as with Nor-11 Case INTR ₌ sabspeiTorgane 20 and the cooling malbetrieb as well as the three passages 6 and the Absehlammauslaß 5 are blocked. All of the housing 12 is set so that the risers 15 not to be tested cold chains will have a free passage and are also connected to the above-mentioned position of the associated three-way hammers ring line 16. Preßluftan- J2 with their associated risers 15 ver circuit 4, emergency water outlet 18, Absehlämmauslaß 5 tied, but abge from the upper ring line 16 and emergency water inlet 6 are shut off. On this separates. The emergency water outlet 18 remains closed. In this way, all fall lines 8 and all riser pipes and through the compressed air connection 4 compressed air is fed into one another 60 of the subsystems of the cooling disk. The leak can then be connected to the known per se. Thereby the natural circulation of the sage will be found. The safety overpressure of the cooling water is stabilized over the entire cooling disk. Valves 19 are to be checked for each arbitrary is required. Of course, stau Presslui can deliver water. In this way, a balance can also be used in another compressed gas, ζ. Β the water supply of the individual subsystems, water vapor. Below the three-way cocks 12 can be enough. ^NEN connections for connecting as required;

vlanometem be provided in order in this way '.ur leak test pressure changes in the cooling chains to be able to measure.

For blow-down, the blow-down outlet 5 opened. All other taps and shut-off devices

remain in the position for normal operation. The blow-down can therefore take place during normal operation take place. The lower ring line 10 serves as a common blowdown ring line for the entire Cooling disk.

1 sheet of drawings

JO9 586/224

Claims (7)

Patent claims: 1. Evaporation cooling system for metallurgical furnaces, in particular for HoChOfCr _1, which has a plurality of cooling boxes, several of which are connected via downpipes and risers to an evaporation vessel and together with this form a subsystem, characterized in that the risers (15) all Subsystems in the area of the exit from the subsystems can be connected to one another by a ring line (16), the ring line (16) being able to be shut off from the atmosphere, a pressurized gas connection (4) and an emergency water outlet (18). 2. evaporative cooling system according to claim 1, characterized in that the case lines (8) of all sub-systems in the area of entry into the sub-system, each through a further ring main (10) can be connected to one another, the further ring line (10) being connected to the atmosphere, a blowdown outlet (5) and an emergency water inlet (6) can be blocked. 3. evaporative cooling system according to claim 1 or 2, characterized in that the risers (15) and / or the case lines (8) individually or jointly for a subsystem of the ring line (16) or the further ring line (10) through locking devices (11, 12, 13, 20) are detachable. 4. VerdampfungsküKsysteni according to claim 1, characterized in that the ring line (16) has one or more safety pressure relief valves (19). 5. evaporative cooling system according to claim 3, characterized in that in the riser (15) a three-way valve (12) is switched on, the third connection of which with the ring line (16) connected is. 6. evaporative cooling system according to claim 3 or 5, characterized in that instead of the Three-way valve (12) a four-way valve (22) is provided, the fourth connection with one of the with the riser (15) directly connected to the cooling box (14) bridging bypass line (24) is connected. 7. evaporative cooling system according to claim 3, characterized in that the individual subsystems are provided with connections for pressure gauges, the connections between locking devices (12) and subsystems.