EP1793166A1 - Method for the inside cleaning of industrial furnaces, silos and such through bombardment with industrial guns - Google Patents

Abstract

Method involves bombarding by means of shots (G) with percussion fuse (4) and by means of loading explosives or pyrotechnical material from an industrial gun operated by compressed air, with misplay of the shot by means of compressed air from a pipe (11).

Description

The invention relates to a method for the internal cleaning of industrial furnaces such as blast furnaces, cement kilns, waste incinerators, coal power plants or other facilities such as large silos, bulk bunker, mixing bunker and the like.

On the inner walls of industrial furnaces, bunkers or the like, an increasingly thick adhesion layer of slag, caking, or encrustation material builds up during operation. From time to time it is necessary to eliminate these buildup to allow for efficient operation. Since such adhesions have considerable thicknesses and are difficult to remove because of their strength and hardness, it is known to carry out the cleaning by bombardment of the inner walls with industrial guns. By this bombardment the attachments are cut off.

With the industrial cannons commonly used today, which are constructed and operated similar to a machine gun, a special cartridge ammunition is fired with propellant located in the cartridge and on the cartridge bottom befindlicher propellant igniter. The projectiles have a diameter of about 15 to 20 mm. The muzzle velocity of these projectiles is in the supersonic range. This is associated with a high kinetic energy of the projectiles and a corresponding enormous surface pressure at the impact on the deposition or encrustation.

Due to the circumstances of the conventional industrial guns and ammunition just described, however, is only a limited use in the above-mentioned scope possible. For example, according to the manufacturer's information of a common industrial cannon and the ammunition to be fired, it is only possible to keep cement rotary stubs acidic. However, it is not possible to remove large deposits of slag or rings in cement kilns.

Furthermore, a use of the industrial cannon is not possible if due to the necessary positioning of the industrial cannon and the dimensions of the furnace would have to be fired at a relatively short distance, since then the kinetic energy would be so high when hitting the floors that it is a breakthrough The slag or encrustation and associated damage or destruction of the furnace lining (chamotte) or furnace wall can come. The same danger exists even when using the industrial gun at firing distances in the usual range, if locally only relatively thin slag or encrustation layers are present and they are penetrated by the floors.

Industrial guns used so far, being like a machine gun and operated with cartridge ammunition with propellant charges, are of very heavy construction and weigh about 100 kilograms. This requires that the transport and the in-position bring by several employees must be made. At inaccessible or hard to reach places in power plants conventional industrial cannons can not be used practically because of their high weight.

It is therefore an object to provide a cleaning method for industrial ovens, bunkers and similar equipment for removing slags, adhesions, incrustations and the like by bombardment of the wall surfaces, in such a way that on the one hand a lighter construction of the industrial guns used is necessary and on the other the risk of damage to furnace linings and the like is reduced.

This object is achieved according to the invention by the method specified in claim 1. Advantageous embodiments of the method according to the invention are the subject of the dependent claims.

The inventive method is thus characterized in that instead of firing the ammunition with propellant charges, the ammunition is fired only with compressed air, and that the projectiles have a Aufschlagzünder and a small explosive charge.

By firing the ammunition with compressed air, the industrial cannon can be built much easier, and the muzzle velocity of the projectiles can be easily adjusted by adjusting the air pressure used in each case to local conditions, so for example increase at a greater firing distance and reduce at a short firing distance, so that the stress an oven or bunker wall is controllable and manageable. Due to the formation of the projectiles with an impact fuze and a small explosive charge, the impacting projectile, which may be lighter than the projectiles fired with conventional industrial cannons, still generates high energy at the point of impact for destroying and knocking off buildup and encrustations, but this effect is more extensive is done and is not limited to the pure bullet cross section, as is the case with the result of extremely high surface pressures in the conventional ammunition.

The invention will first be explained in more detail with reference to a few specific examples of use.

In Zementdrehöfen forms during the manufacturing process often a so-called ring caking on the furnace walls, which can be up to about 0.5 m thick and can extend over several meters kiln length. With furnace diameters in the range of about five meters, the weight of these ring caking moves in the ton range. Such enormous Ringanbackungen could not be removed with a previous industrial cannon or the ammunition thus fired or, if at all, only with several thousand shot. During the firing process, the speed of the furnace had to be reduced. Thus, the output of the furnace was reduced and caused economic failure, quite apart from possible damage to the furnace wall. If the oven could not be cleaned, the last step was to stop the oven and cool it down so that the cold ring caking could be removed manually. The inventive method, it is now possible, even over long distances (about 50 meters) targeted shoot down this Ringanbackungen.

In waste incinerators complex demands on cleaning methods are made by an industrial cannon, namely to the fact that, for example, in the combustion chamber of the incinerator pushed together and zusammengebackene waste mountains are shot. Depending on the design, slag accumulations with a thickness of up to about 0.5 m also occur in the combustion chamber. It is necessary to shoot down these slag accumulations, but without damaging the underlying chamotte lining. In the field of flue gas cleaning, heat exchangers are subject to buildup, which must be gently removed. These tasks were difficult or impossible to master with a conventional industrial cannon. With the method according to the invention such cleaning tasks can be done efficiently.

In some waste incineration plants, the slag from the combustion process is wetted with water for cooling and transported into a slag bunker. Depending on the residence time of the slag in the slag bunker, the slag sticks or dries to the walls and becomes as hard as concrete. When removing the slag from the slag bunker by excavating up to several tons of heavy attachments hang on the walls, which can no longer be eliminated by conventional means, especially with the conventional industrial gun. Here, too, the method according to the invention, with which adhering slag can be fired accurately, leads to remarkable results.

Even in brown and hard coal fired power plants large scale slag accumulations are due to the enormous size of the furnace chambers abzutragen. It should be noted, however, that there the slag can be only a few centimeters thick depending on occurrence, and that underlying pipe systems that are used for heat generation, must not be damaged. Therefore, the method according to the invention is particularly advantageous here, because the cleaning effect is provided by the explosion pressure of the projectiles provided with impact fuze and not by the kinetic energy of the projectile.

In expanded clay works, during the manufacturing process, material collections in the furnace that have the shape of a glowing sphere occur. There is the peculiarity that this glowing ball is not solid. It resembles a swirling mass like liquid rock. With the previous ammunition of the industrial cannon such a mass accumulation can not be destroyed, but the conventional bullets due to their high kinetic energy simply pass without significant influence of this mass through them. With the method according to the invention, however, such a glowing ball can be destroyed extremely effectively.

In bulk silos, in open pit, bulk solids and wherever loose material is used and stored and this is produced by solidification, mixing with water, for example by precipitation, caking and encrustations, blast furnace facilities, where ores, slags and the like produce caking on the walls, These can be removed with the inventive method using an impactor ammunition targeted, accurate and fast, without damaging the walls.

In the embodiment of the method according to the invention, a pressure adjustment of the air pressure in the industrial gun of about 20 bar is preferred. Thus, a muzzle velocity of about 130 m / s (equivalent to about 460 km / h) is achieved in a Aufschlagzündergeschoss with a bullet weight of about 100 g. As already mentioned, depending on the intended use, the pressure setting can be increased or decreased in order to achieve a greater or smaller initial speed of the projectile or impact velocity of the projectile. When providing different projectiles with different floor size or different bullet weight, the pressure setting can also be adjusted accordingly.

The impact fuze projectile may be equipped with different pyrotechnic or explosive charges, depending on the intended application. Thus, a wide variability and adaptability in terms of purpose and effect is possible.

It is understood that also by the configuration of the projectile and the explosive charge in the projectile, the projectile effect can be varied in a wide range. Because so that the shape and effect of each pressure wave generated can be changed. So it is possible, for example, to make the configuration so that a concentrated Pressure wave produces a strong depth effect on the impact surface, or produces a broader, but less surface pressure having surface effect.

The compressed air industrial gun can be compact in design and its weight is ready for use at around 15 kg. That's only about one-sixth the weight of a conventional industrial cannon for firing cartridge ammunition. The industrial gun to be used in the method according to the invention can thus be conveniently transported by a single person, brought into firing position and operated.

The ammunition is preferably constructed so that it consists of only three parts, namely projectile body, cap and impact fuze and decomposed nu in these three parts. Therefore, the ammunition is safe and produces no uncontrolled flying splinters or fragments.

Fig. 1

in perspektivischer Darstellung ein Geschoß mit Aufschlagzünder,

Fig. 2

eine Ansicht einer druckluftbetriebenen Industriekanone zum Verschießen von Geschossen nach Fig. 1, und

Fig. 3

im Axialschnitt den in Fig. 2 innerhalb des strichpunktierten Kreises liegende Teil der Industriekanone mit eingelegtem Geschoß nach Fig. 1

This embodiment of the method according to the invention used industrial gun and the impact detonator ammunition will be explained in more detail below with reference to the accompanying drawings. In the drawings shows:

Fig. 1

in perspective a projectile with impact fuse,

Fig. 2

a view of a pneumatic industrial gun for firing projectiles of Fig. 1, and

Fig. 3

in axial section that in Fig. 2 within the dot-dashed circle lying part of the industrial cannon with inserted projectile according to Fig. 1st

Fig. 1 shows in perspective view a bullet with impact fuze for use in the inventive method. The projectile has, for example, a diameter of about 40 mm and a length of about 130 mm. It consists of a rear shell forming projectile shell or projectile body 1 with the flight stabilization serving ribs 2, a front part forming cap 3 and arranged at the top of the cap 3 Aufschlagzünder 4. The enclosed by the projectile body 1 and the cap 3 Cavity is filled with an explosive charge of explosive or pyrotechnic material.

Fig. 2 shows an industrial cannon for firing from the projectile of Fig. 1 in side view. It has a tube 11, a projectile chamber 12 at the rear end of the tube, which can be closed with an axially displaceable closure sleeve 13, and a cannon body 14 with a rear handle 15 and operating handles 16 and a compressed air connection 17th

Fig. 3 shows the interest here range of industrial gun, which can be operated with compressed air from a compressed air cylinder, which is connected via a hose to the compressed air port 17. This is the projectile chamber 12 at the rear end of the tube 11. The projectile chamber has an opening 21 and an inner tube 22 which is axially displaceable together with the axially displaceable locking sleeve 13 to expose the opening 21 and the insertion of a To enable bullet G In the illustrated position, the closure sleeve 13 is shown with the inner tube 22 and inlaid G in the retracted closed position in which the projectile G is ready to fire in the cannon.

Claims (6)

A method for removing buildup, caking, encrustation or the like of walls of industrial furnaces, bunkers and similar installations or for shattering accumulations of material by firing ammunition from an industrial gun,
characterized in that the firing by means of projectiles (G) with impact fuze (4) and a charge of explosive or pyrotechnic material from a compressed air operated industrial gun with firing of the projectiles by means of compressed air from a tube (11). The method of claim 1, wherein the industrial gun is operated with compressed air in a pressure range of 10 bar to 40 bar. The method of claim 2, wherein the industrial gun is operated with compressed air having a pressure range of 15 to 25 bar. Projectile for use in the method according to one of claims 1 to 3, consisting of a projectile body (1, 2, 3) with impact fuze (4) and a filling of explosive or pyrotechnic material. A projectile according to claim 4, wherein the projectile body consists of a rear part (1) which tapers towards the rear and has stabilizing fins (2) formed on it, and a front part (1) in the form of a lid or cap, the rear part and the front part Part together enclose a chamber for receiving the filling. A projectile according to claim 2, wherein the impact fuze (4) is arranged at the tip of the front part (3).

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