Method for lighting fire and apparatus for carrying out said process

The invention relates to a method for firefighters in enclosed spaces and buildings in which by introducing at least an inert gas, the oxygen content the atmosphere in the area of ​​the fire source below a required to maintain the fire Value is lowered. It further relates to a Device for carrying out such a method.

Firefighters in closed rooms where deleted not by water jet, foam or powder may be or may, preferably found in the past Halon as extinguishing agents. After its Prohibition has been as an alternative among others, a The method of the aforementioned type is proposed in the inert gas in the areas affected by fire Space is blown to this way the oxygen content the therein atmosphere among necessary for the further maintenance of the fire to squeeze value from about 12 to 15 percent. As possible inert gas generators were here already considered propellant charges, the high-nitrogen in their reaction Gases developing. However, included these gases usually in addition to nitrogen (N₂) often even carbon dioxide (CO₂) In a proportion of up to 20%. This is always problematic when be in the room where the fire has broken out staying even those the room if possible should not leave or can not. Because of the damaging effect of increased CO₂Concentrations in the air we breathe should therefore by Possibility the already having because of the fire Carbon dioxide-enriched atmosphere is not with additional CO₂ are loaded from the extinguishing gas. In addition, the reaction gases such blowing rates yet often with carbon monoxide (CO), hydrogen (H₂) and methane (CH₄) Combustible fractions. After all these propellant charges at their burnup yet dusty slag eject their share up to may be 40 percent by weight of the fuel composition.

In addition, solid propellant charges have already been on the Basic sodium azide (NaN₃) Has been proposed, as described in miniaturized form use in vehicle airbags find. Although these have the advantage that they as provide reaction product nearly pure nitrogen, but is its use on a larger scale the Toxicity against the starting products. be added corrosive and hazardous when they burn Dusts intercepted by special measures must be neutralized or.

The use of solid propellant charges has also the drawback that these successful after once ignition completely burn usually and that a new Ignition, such as a flare-up a supposedly already deleted Brandes, not is possible. Finally, would the use of gas generating systems with solid generators at a Use in larger rooms or in a fire extinguishing piping for larger building wings modularization with many individual generators and corresponding terminals require.

It is therefore an object of the invention, a method of type described above so that a Extinguishing gas supplies, that is free from carbon dioxide or other harmful or oxidising Shares and of dust particles, which turned off many times as may be required to operate and both located for permanently installed firefighting systems as for mobile, autonomously operating facilities suitable. Another object of the invention is to provide an apparatus provide that a simple on possible and effectively carrying out the invention Process allows.

The invention solves the first object by a method, in which a reaction of ammonia (NH₃) With Ambient air nitrogen (N₂) And water vapor (H₂O) produced and supplied as an extinguishing gas mixture of the fire will. The solution of the further object is achieved by means a so-called small gas turbine system as in Principle in a similar form as an engine or auxiliary power plant (APU = "auxiliary power unit") in Aircraft is used, which in this system However, for performing the method according to the invention Ammonia (NH₃) Instead of the usual used kerosene as fuel. Similar small gas turbine plants see in addition also in stationary operation as small power stations using, where they however also operated with hydrocarbons as fuels will.

The invention thus has the advantage that it by the use of such, the prior Technology largely corresponding system on the one hand already proven and reliable and also immediately available components is based, on the other hand, by the inventively provided using ammonia as Fuel for this plant an absolute CO₂-free exhaust supplies, which is also free of dust particles. they can by supplying simple and in large Quantities liquid ammonia storable on any long periods of time to operate, being arbitrarily is often switched off again and bootable. In addition, their operation by simply refueling of ammonia maintained or her ready for operation waiting state be guaranteed.

The device according to the invention can be used both stationary operated and connected to a fire extinguishing piping and in the form of a mobile unit for a autonomous operation are provided. Your Start can, as with kerosene-powered systems, electro - thermally or via a pilot flame. After all the device of the invention has in its preferred embodiment, a sensor-controlled Temperature control both the working gas before entering in the turbine as well as the inert gas prior to the Feeding into the fire extinguishing piping. This is about a water injection realized. The following text the invention by way of shown in the drawing Embodiment are explained in detail. The FIGURE shows a schematic representation of the Construction of an apparatus for the production of carbon dioxide-free Inert gas for fire-fighting purposes. Of the Construction of this apparatus substantially corresponds to that of a small gas turbine plant as a Auxiliary power plant or APU in aircraft is used.

is In this system, as indicated by arrow, sucked ambient air from a compressor (1) and in compressed state pressed in a combustion chamber (2). Here, an injection valve (3), ammonia (NH₃) supplied, which by means of a pump (4) from a reservoir (5) and conveyed to the combustion chamber in the (2) prevailing pressure is brought.

In the combustion chamber (2) according to the reaction equation<st32:che xmlns:st32="http://www.matrixware.com/ns/st32/">4 NH₃ + 3O₂ + 3 XN₂ (3 X + 2) N₂ + 6H₂O</st32:che>wherein X is the nitrogen content of the air, based on the Oxygen content, means nitrogen and water vapor as components of a for firefighters generates suitable inert gas mixture.

To an oxygen-free as possible to the combustion exhaust gas generate, the ratio of fuel to air should the stoichiometric ratio correspond. As this but on the other hand to increased combustion end temperatures would lead, in which described here Embodiment, the temperature of the

Combustion gas by injected water on a lower value placed. This water is a second pump (6) from a second reservoir (7) Transfer and dosing. The two pumps (4) and (6) are driven by a transmission (8), on the a common shaft (9) with the compressor (1) as well as is arranged with a turbine (10). Latter is produced by the combustion chamber (2) exhaust driven and promotes this in a mixing chamber (11) where it is carried out by means of a valve (12) Water injection to the for firefighters cooled suitable temperature and in a fed fire extinguishing pipe system (13).

Instead of the reservoir (7), it is understood in the context of the invention also possible that the to draw water from an existing pipeline network. The injection of water both into the combustion chamber (2) and into the mixing chamber (11) each is a sensor controller controls the two on the Injection valves (12) or (14) acts. For the operation the investment required intake air can either be taken directly from the atmosphere, which preferably is then the case when a stationary Installation with a connection to a fire extinguishing piping is provided, or from the room in which the Fire has broken out. In this latter case, it is advantageous, if the fuel supply via the controlled valve (3) by means of a further sensor is that it the decreasing oxygen content of this Atmosphere is matched.