EP0349865B1 - Installation for burning and incinerating explosive substances and objects affected by such substances and process for operating the installation - Google Patents

Abstract

Method and apparatus for burning and incinerating explosive substances and objects affected by such substances. For combustion, explosive substances, such as rocket propelling charges, propellants, explosives or articles affected by these, are arranged in constant part quantities on transportable supports (5) in a charging region (4), the supports are transported one after another to a burning place (3) which is arranged, preserving its character as an open burning place, in a safety building (1) with a blowout wall (2), which is provided in part-open style, and are there ignited and burnt off by means of a remotely-operated burner, the waste gases being sucked off and conveyed to a cleaning arrangement, in which impurities are removed from the waste gases and disposed of in an environmentally suitable manner, while the cleaned waste gases are delivered into the atmosphere. Subsequently, the supports with the residues of the incinerated explosive substances are transported further and cooled, freed of the incineration residues, cleaned and again provided with explosive substance. <IMAGE>

Description

The invention relates to a system for burning off and burning explosives such as explosives, propellant powder, rocket fuels, igniters, igniters and pyrotechnic substances, propellants and objects associated therewith, and a method for operating this system.

It is known to destroy explosives that are no longer usable and that can no longer be regenerated with reasonable effort, whether they are from obsolete stocks or waste from production, packaging or the like, taking into account the corresponding safety regulations. This can be done chemically, by blasting or by burning or burning.

Destruction by chemical means is only possible to a limited extent and involves a relatively large amount of effort, in particular for the disposal of the resulting waste products. When destroyed by blasting, there are relatively large environmental impacts from noise and, above all, this type of destruction is associated with considerable risks. In the preferred and most widespread manner of destroying explosives, propellants, rocket propellants or the like, as well as equipment, tools, etc. contaminated with them by burning or burning, it is known to carry them out in furnaces or outdoors.

The destruction of explosives by fire can be either without the aid of a fuel, ie burning, as well as with the aid of a fuel, i.e. burning. Insofar as the term "burning" is used in the following, this should always also include "burning".

In the case of continuous combustion of explosives in rotary kilns or in a fluidized bed, the explosive must be transferred to a slurry and / or portioned before being introduced into the furnace in such a way that there is no risk of detonation. Such systems are very complex and very expensive in terms of both investment and operating costs. Taking into account the requirement contained in the relevant guidelines for the destruction of explosives of the professional association of the chemical industry to destroy the explosives separately according to species, such systems are also only useful for the destruction of very large quantities of specially prepared explosives.

Such a process is described in US-A-3,848,548, where the explosive is burned as an aqueous suspension in a rotary kiln under conditions (650 to 1200 ° C) which involve the gradual evaporation of the water from the suspension, the drying of the explosive and allow the subsequent ignition of the explosive.

In contrast, according to the valid guidelines of the professional association, the permissible burning of explosives outdoors, ie on an open fire place, the economical elimination of them even in small and very small quantities, whereby expensive facilities can advantageously be dispensed with, and there is no need for special preparation of the explosives, for example into a meterable slurry. Due to the requirement to separate the explosive by type, as well as the other relevant provisions such as determining the quantities per fire and area, maintaining certain safety distances between several fire places of a fire place and between it and systems, buildings, houses, traffic routes etc. within and outside the company premises, there is a batch operation. This enables optimal adaptation to the type, quantity and preparation of the explosives to be destroyed. Batch-based combustion therefore allows extraordinary flexibility in handling explosives and offers a high degree of handling safety. In particular, batch-wise combustion enables economical and simple destruction of explosives that cannot be handled without danger.

This in the "Explosive destruction guidelines" No. 5 of the professional association of chem. Industry, edition 4/82 and recently also in the accident prevention regulation blasting work (VGB 46) way of destruction of explosives outdoors by burning in long strips or by burning in an open wood fire has the considerable disadvantage that a complete burning or a complete combustion is not guaranteed and the exhaust air pollution by Soot, dust, acidic gases (HCl, HF, NO _x , SO₂, phosphorus pentoxide, etc.) and heavy metals can go far beyond what is permitted in TA-Luft. For example, the black smoke mushroom that is known to rise above the fire place when trinitrotoluene (TNT) burns is symbolic of the environmental impact during the burning of explosives outdoors. Such environmental pollution when disposing of explosives is, however, not compatible with the applicable legal regulations, such as with TA-Luft and the Waste Disposal Act, or with today's understanding of the environment.

The invention has for its object to provide a system for burning off explosives, propellants and objects afflicted with them, while observing and complying with the applicable regulations and while maintaining the character of an open fire place for the fire site an environmentally friendly and environmentally friendly destruction of explosives enables a safe and economical way.

This object is achieved by a system for burning off and burning explosives, propellants and objects afflicted therewith, which is characterized by a security building 1 provided with a partially open construction discharge wall 2, a fire site 3 formed therein as a fixed fire place, a plurality of portable explosive carriers 5, a loading station 4 for the explosive carriers separated from the fire site 3 by a safety device, one downstream of the fire site 3 by a safety device from this separate cooling zone 19 for the explosive carriers, a device downstream of the cooling zone and preceding the loading zone 4 for emptying and cleaning the explosive carriers, a device for extracting the exhaust gases produced during combustion and an associated device for cleaning the exhaust gases. Advantageous further developments of the invention are the subject of dependent claims 2 to 13.

The present invention furthermore relates to a method for operating the system according to the invention explained above, in which the explosives to be burned and the objects afflicted with them are successively transported in parts to the fire site, ignited and burned there, the combustion exhaust gases are sucked off and the impurities contained therein are removed and disposed of in an environmentally friendly manner and the cleaned exhaust gases are discharged into the atmosphere.
The process is preferably carried out in such a way that the exhaust gases are subjected to post-combustion before the cleaning is carried out and the ashes obtained are disposed of.
Another preferred embodiment of this method is that the exhaust gas flow is connected to a fresh air source 33 and the volume flow of exhaust gas and fresh air is controlled so that it has a constant value for all operating conditions.

The system and the method used to operate the system according to the invention ensure that all the advantages of the closed combustion of explosives in a fluidized bed or in furnaces, in particular in rotary kilns, namely the detection of the pollutants occurring, in particular the cleaning the exhaust gases generated during combustion, in conjunction with the particularly simple, inexpensive and very safe type of combustion outdoors, ie in an open fire place, can be achieved, so that it is now possible to carry out the combustion of explosives of all kinds in an environmentally friendly manner.

Furthermore, compared to the previously known type of combustion of explosives outdoors, there are the advantages that there is no inadmissible contamination of the fire place floor, that the slag is filled automatically into containers, that optimum safety is guaranteed for the operating personnel and that the burning conditions of the Weather are independent, so the combustion can be carried out at any time.

Figur 1

in einer Draufsicht in schematischer Darstellung eine gemäß der Erfindung ausgebildete Anlage,

Figur 2

einen Schnitt gemäß Linie A-A der Figur 1 und

Figur 3

in einer Seitenansicht ebenfalls in schematischer Darstellung eine geringfügig modifizierte Ausführungsform einer erfindungsgemäßen Anlage.

The invention is shown in the drawing in exemplary embodiments and is described with reference to these in the following. Show it

Figure 1

a plan view in a schematic representation of a system designed according to the invention,

Figure 2

a section along line AA of Figure 1 and

Figure 3

In a side view, also in a schematic representation, a slightly modified embodiment of a system according to the invention.

In Figure 1, the security building 1 is provided with the partially open construction discharge wall 2, so that for the fire site 3 the character of a open fire place is preserved. The arrangement and design can be made, for example, so that a sufficiently high open slot is present over the entire length of the outlet wall 2 between the latter and the roof, not shown, and the roof projects so far beyond the outlet wall that it is ensured that the interior of the building is against Weather influences are protected. Numerous other embodiments are conceivable. The explosive to be destroyed, for example a rocket propellant, is placed in the area of the covered feed 4 in suitable and permissible quantities on explosive carriers 5, preferably tubs made of steel, and transported there by the circulating transport device 6 to the fire site 3. The explosive carriers 5 preferably pass individually through the security door 7, which can be operated by remote control, and first reach the standby position 8, from where, after the door 7 has been closed and the additional security door 9 has been opened, which thus form a lock with one another, through the remote-controlled operating device, namely the hydraulic cylinder 10 of the fire site 3 are supplied. After closing the door 9, the explosive located on the explosive carriers 5 is ignited and burned off by means of preferably remote-controlled burners or the like, not shown, or the like.

Above the fire site 3 of the system, the hood 11 is preferably arranged for collecting and extracting the exhaust gases released during the combustion. This is connected to the exhaust gas afterburner 13 via the exhaust pipe 12. Via the pipe 14, this is connected to the scrubber 15, which in turn is connected to the exhaust stack 17 via the fan 16.

Instead of a special chimney, another possibility could be provided for the discharge of the cleaned exhaust gases into the atmosphere, for example the fan 16 could be arranged in front of the scrubber 15 in the line 14 and an exhaust connection or the like could be fitted on the scrubber 15.

After the explosive has been burned, the explosive carrier 5 is transported into the cooling area 19, passing the remote-controlled security door 18, where the explosive carrier 5 is cooled, if necessary, by spraying with cooling water or air on the underside.

From the cooling zone 19, the explosive carrier 5 then passes the further security door 20 to the emptying area 21, where the combustion residues remaining in the explosive carrier 5 are emptied into the container 22. With the cleaning device 23, the explosive carrier 5 is cleanly cleaned and then returned to the loading area 4 for refilling by means of the circulation transport device 6, passing through the opening 25 provided in the partition 24.

As can be seen from FIG. 1, a large number of explosive carriers 5 are arranged on the circulating transport device 6 and there are several each in the loading area 4, at the fire site 3, the cooling area 19 and the emptying and cleaning areas 21 and 23 Explosive carrier 5, which allows loading and burning of explosive in a relatively dense sequence. By adjusting the cycle time to the Burning time can be achieved that a quasi-continuous process takes place. By dividing the explosive into solid portions, depending on the burning time, quantity and cycle time, the power of the energy and flue gas release can be regulated, so that from the conventional open fire place with more or less uncontrolled flue gas and energy release by the measures according to the invention now an open Fire place with conditioned conditions has become.

As can also be seen from FIG. 1, the hood 11 is designed such that there are preferably several explosive carriers 5 in its area at the same time. In coordination with the selected cycle time, it can be achieved that there is at least one currently in the process of being burned out, one in full fire and one in the process of being burned in the area of the extractor hood 11, thereby equalizing the amount of combustion gas. Depending on the type of explosive to be burned, an arrangement and design can also be made independently of this in such a way that there are only a few explosive carriers 5 in the individual areas, particularly preferably only one single explosive carrier 5 at the fire site 3.

For the hydraulically and electrically actuated parts and for the preparation of the scrubber 15 and the disposal of the pollutants which have been eliminated from the exhaust gases during their cleaning, the system according to FIG. 1 naturally has the facilities required for this, but not shown here.

As can be seen from FIG. 2, the extractor hood 11 extends sufficiently far laterally beyond the explosive carrier 5 and also relatively far down to the explosive carrier 5, so that a reliable detection of all exhaust gases by the extractor hood 11, but also sufficient access to the items required for the combustion Atmospheric oxygen is ensured. The height or the volume of the hood 11 is of course chosen so that it can safely absorb the released volume of exhaust gas when burning any kind of explosives.

In the exemplary embodiment in FIG. 3, in which the same reference numerals are used again for the same parts, the explosive carriers 5 are arranged on the circulation transport device 6, the explosive carriers 5 preferably being transported individually to the fire site 3. Above the explosive carrier 5 'provided with a burning explosive, the chimney or exhaust hood 11 is arranged, which is preferably connected to the afterburning furnace 13 via the line 14. This is provided on its underside for the removal of ash with the flap 32. The afterburning furnace 13 is connected to the exhaust gas cleaning device or the scrubber 15 via the line 14. In order to have continuous conditions even with discontinuously operated combustion and afterburning at the scrubber 15, the automatically regulated fresh air flap 33 is installed between the afterburning chamber 13 and the scrubber 15, so that the volume flow of exhaust gas and fresh air is constant for all operating conditions. This has the advantage of minimal energy costs for the afterburning chamber with discontinuous operation, optimal conditions on the scrubber due to constant exhaust gas flow and low susceptibility to faults, since the fan 16 does not need to be regulated.

The scrubber 15 is supplied near its lower end via line 34 with fresh water and, via line 35, tap water provided with excretions from the exhaust gas and fed to the settling tank 31, from which the settled sludge can be removed via the flap 36 located at the lower end. A neutralizing agent, for example sodium hydroxide solution, is fed to the washer 15 from the container 38 via the line 37 and is mixed with fresh water at several different level heights and sprayed into the washer 15 via the pump 40 arranged in the line 49. The exhaust gas freed from the impurities still present is removed from the scrubber 15 at its upper end via the line 41 and, via the fan 16, to the exhaust gas chimney 17 near its lower end and discharged into the atmosphere via its upper end. To ensure undisturbed operation of the system, the temperatures in the lines 12, 14 and 41 are monitored by means of the control devices 42, 43 and 44 and the pH value of the washing liquid sprayed into the washer is also monitored by means of the line 49 on the one hand and with the Pump 39, on the other hand, connected to a signaling control device 45 controlled in the required manner. Finally, in the interest of an undisturbed operating sequence, the liquid levels in the scrubber 15, in the settling tank 31 and in the sodium hydroxide tank 38 are also monitored and regulated by means of the level controllers 46, 47 and 48, which are again provided with signal transmitters if necessary.

Since, depending on the type of explosive to be burned and the flue gas composition, post-combustion of the flue gases is not always necessary, it is advisable to design the system so that the post-combustion device can be switched off and the flue gases that develop during combustion are fed directly to the scrubber .

The ash removed from the post-combustion furnace 13 and the sludge removed from the settling tank 31, as well as the washing water discharged from the settling tank 31 via line 50, must be disposed of in accordance with the applicable regulations.

If operated appropriately, the system can be equipped with a waste heat recovery device (not shown) in order to improve the economy.

The entire system is preferably provided with a video device, in particular for monitoring the burning process, so that it is possible at any time to intervene in the operating sequence in the desired or required manner.

Claims (13)

1. An installation for deflagrating and burning explosives, propellants and items contaminated therewith, characterised by a safety building (1) provided with a blow-out wall (2) constructed in a partially open manner, a burning point (3) which is designed therein as a fixed burning site, a plurality of transportable explosives carriers (5),
   a loading station (4) for the explosives carriers which is separated from the burning point (3) by a safety means,
   a cooling zone (19) for the explosives carriers which succeeds the burning point (3) and which is separated therefrom by a safety means,
   a device for emptying and cleaning the explosives carriers which succeeds the cooling zone and precedes the charging zone (4),
   a means for drawing off the waste gases produced upon combustion, and
   a device for purifying the waste gases which is connected thereto.
2. An installation according to Claim 1, characterised in that the burning point (3) is covered over by a fume hood (11).
3. An installation according to Claim 1, characterised in that the safety means between the burning point (3) and loading station (4) and between the burning point (3) and emptying zone (21) are designed as safety gates.
4. An installation according to one of Claims 1 to 3, characterised in that an after-burning furnace (13) is located between the means for drawing off the waste gases and the device for the purification thereof.
5. An installation according to one of Claims 1 to 4, characterised in that the connecting pipe between the means for drawing off the waste gases and the waste gas-purification device, and between the after-burning furnace and the waste gas-purification device communicates with a fresh air source (33) which is controlled by means of a control means (42) located in the waste gas line (12).
6. An installation according to one of Claims 1 to 5, characterised in that the explosives carriers (5) are located on a circulating transport means (6).
7. An installation according to Claim 6, characterised in that the circulating transport means (6) transports the explosives carriers (5) individually to the burning point (3).
8. An installation according to one of Claims 1 to 7, characterised in that the fume hood (11) covers a plurality of explosives carriers (5) simultaneously.
9. An installation according to one of Claims 1 to 8, characterised in that the burning point (3) is constructed with preferably remote-controlled burners for igniting the explosive.
10. An installation according to one of Claims 1 to 9, characterised in that the installation is designed with a video means for monitoring in particular the deflagration operation.
11. A method for operating the installation according to Claim 1, characterised in that the explosives to be burned or the articles contaminated therewith are transported successively in partial quantities to the burning point, are ignited there and deflagrated, that the waste gases from the combustion are drawn off, the impurities contained therein are removed and are disposed of in environmentally friendly manner, and that the purified waste gases are discharged into the atmosphere.
12. A method according to Claim 11, characterised in that the waste gases are subjected to after-burning before purification is carried out, and the ash produced thereupon is disposed of.
13. A method according to Claim 11 or 12, characterised in that the waste gas stream is connected to a fresh air source (33), and the volume flow consisting of waste gas and fresh air is regulated such that it has a constant value for all operating conditions.

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