CZ291724B6 - Method and device for a burner shut off - Google Patents

Abstract

In the present invention there is disclosed a method for shutting of a burner (5', 5'', 5''') having at least one supply pipe for a fuel gas/oxygen mixture, wherein the method is characterized in that simultaneously with the interruption of the flow of the fuel gas/oxygen mixture to the burner (5', 5'', 5'''), an inert, respectively cleansing gas is introduced. Device for making the method comprises a plurality of burners (5', 5'', 5''') having each at least one supply pipe (3', 3'', 3''') for a fuel gas/oxygen mixture, whereby in said supply pipes (3', 3'', 3''') there is arranged at least one regulating and/or cut-off valve (d', d'', d'''). Said supply pipes (3', 3'', 3''') for the fuel gas/oxygen mixture are provided downstream said regulating and/or cut-off valve (d', d'', d''') with inlet of at least one supply pipe (4', 4'', 4''') for inert, respectively cleaning gas and said supply pipe (4', 4'', 4''') for inert, respectively cleaning gas is provided with at least one regulating and/or cut-off valve (e', e'', e''').

Description

Technical field

The invention relates to a method for disconnecting a burner with at least one supply line for a fuel gas / oxygen mixture. The invention further relates to an apparatus for carrying out the method, which comprises a plurality of burners with at least one supply line for the fuel gas / oxygen mixture, wherein at least one control and / or isolation valve 10 is provided in the supply lines.

BACKGROUND OF THE INVENTION

In order to supply the burner with the fuel gas / oxygen mixture, oxygen and fuel gas, e.g. acetylene, are usually supplied via two separate supply lines and mixed therein in the desired mixing ratio. The fuel / oxygen mixture thus obtained is then fed to a burner via a supply line. The burner is usually disconnected by closing the valves in the supply lines upstream of the mixing station. Disconnecting, however, in this method, the flames are re-burned into the burner, which can lead to endangering of the operating personnel and damage to the combustion plant.

DE 38 25 721 discloses a method and apparatus for connecting and disconnecting a burner. In this case, the supply lines equipped with a non-return valve downstream of the non-return valves are introduced with inert or non-return valves. purging gas to make inert, respectively. the purge gas had a higher pressure than the combustion gas supplied in the supply lines; of the flushing gas by the burner terminates after the flame ceases.

The introduction of inert, respectively. purging gas into the supply lines with a higher pressure than the combustion gas supplied in the supply line is caused by the connection of the inert or resp. The purge gas flows to the burner only inertly, respectively. purging gas. In the case of burner disconnection, this means that by opening the inlet of the inert or resp. purging gas interrupts the further combustion gas supply due to non-return valves and flowing inert or resp. The scavenging gas dilutes the combustion gases that are still available and pushes them out of the burner, causing the burner to finally extinguish.

Another method of disconnecting the burner is known from U.S. Pat. No. 2,938,577. In this method, the combustion gas line is first closed by means of a valve, while the oxygen supply line remains open. In the course of this, the combustion gas supply line is purged 40 and purged with nitrogen or other non-inflammable gas, so that the supply line system is filled with a non-combustible or non-combustible gas supply system. non-inflammable gas. After the flame has been extinguished, the oxygen supply line is also closed by means of a valve.

However, both methods have disadvantages. In the case of published application DE 38 25 721 a comparatively costly switching is required. In addition, at least one non-return valve must be provided in all supply lines. This type of operation is also not suitable for multi-burner systems. In such multi-burner devices, a plurality of burners are supplied through a corresponding number of supply lines, but these are supplied with the fuel gas / oxygen mixture from only one mixing station.

A disadvantage of the method of U.S. Pat. No. 2,938,577 is that the oxygen supply is not interrupted at the same time as the fuel gas supply line is closed. As a result, oxygen is not necessarily consumed. Moreover, this method is also not suitable for use in multi-burner devices.

-1 CZ 291724 B6

DE 20 18 187 also discloses a device consisting of at least one burner with at least one supply line for a fuel gas / oxygen mixture. Furthermore, this device has an inert or gas supply line. purging gas, which flows into the common feed line 5 of the fuel gas / oxygen mixture. However, it is disadvantageous that, when the inert or resp.

At the same time, all burners are disconnected from the purge gas, so this device is not suitable for multi-burner devices.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for disengaging a burner which, respectively, is provided. which allows safe disconnection with slight loss of oxygen and / or fuel gas and is also particularly applicable to multi-burner systems.

This is achieved according to the present invention by a method of disconnecting the burner with at least one supply line for the fuel gas / oxygen mixture by simultaneously feeding the burner with an inert or gas-fired gas / oxygen mixture to the burner. purging gas.

Preferably, they are inert or non-inert. The scavenging gas uses nitrogen or a nitrogen-containing gas mixture, in particular air or compressed air. In principle, all inert gases, i.e., all noble gases, can be used in the process according to the invention. However, the use of (compressed) air or nitrogen is particularly advantageous because of the cost and also because of the suitable properties.

As already mentioned, the invention further relates to an apparatus for carrying out a method for disconnecting a burner, the apparatus for carrying out the method consists of a plurality of burners with at least one supply line for fuel gas / oxygen mixture, provided in the supply lines with at least one control and / or isolation valve. According to the invention, at least one supply line for the inert or gas supply lines flows into the supply lines for the fuel gas / oxygen mixture downstream of the control and / or isolating valve. purging gas and supply lines for inert and / or inert gas. the purge gas has at least one regulating and / or isolating valve.

Of course, the term control and / or isolation valve is to be understood as including a valve which fulfills both functions.

Overview of the drawings

The method according to the invention as well as the device according to the invention and their further embodiments are explained in more detail by means of figure 1.

DETAILED DESCRIPTION OF THE INVENTION

1 shows a multi-burner apparatus, for the sake of clarity only three burners 5 ', 5 and 5' are shown. In fact, multi-burner devices have up to 50 or more burners 5 ', 5 and 5'.

Oxygen to the mixing station c is supplied via line 1 and valve a, and fuel gas such as acetylene is supplied via line 2 and valve b. The fuel gas / oxygen mixture formed in the mixing station c is subsequently passed through lines 3 and 3 ' 3 'and via valves ï. d, respectively. d 'supplies burners 5', 5 and 52

-2GB 291724 B6

Via supply lines 4 and 4 ', 4, respectively. 4 'of the inert, respectively. purging gas with a given supply line 3 ', 3, respectively. 3 'of the fuel gas / oxygen mixture and thereby of the burners 5', 5 and 5 'supply inert or resp. purging gas. Supply lines 4 and 4 ', 4 and 4', respectively. 4 'of the inert, respectively. of the purge gas are closed during the combustion phase by means of valves e ', e, 5 and 5, respectively. E'.

If only the burner 5 'is to be disconnected, the valve d' is closed and the fuel gas / sieve mixture is interrupted via lines 3 and 3 'to the burner 5'. Simultaneously with the closing of the valve 1 ', the valve e' in the supply line 4 'of the inert and purging gas opens, so that only the inert or respiratory gas flows into the burner 5' from the supply line 4 '. purging gas, and flushing it. By means of the method according to the invention, respectively. The device according to the invention thus provides a reliable disconnection also for the individual burners 5 ', 5, 5' of the multi-burner device. the device according to the invention can be realized especially in multi-burner devices having only one mixing station c.

Preferably, they are in the supply lines (s) 3 ', 3, 3' for the fuel gas / oxygen mixture and / or the supply lines (s) 4 ', 4, 4' for the inert and resp. purge gas provided with non-return valves - not shown. These can be adjusted downstream of the valves d1, d. d 'and e', e, respectively. E'. Thus, it is conceivable that the necessary isolating valves d1, d3 and d3 are respectively provided. 20 and e ', e', respectively. e 'already have a check valve function. Non-return valves of this kind are used so that the control and / or isolating valves d, d and d are not fully closed. ï, respectively. if the control and / or shut-off valve e ', e and / or the shut-off valve is not fast enough. e 'the flow of the inert and resp. purging gas into the feed line (s) 3 ', 3, 3' of the fuel gas / oxygen mixture of the additional gas, respectively. of the other burner (s) 5 ', 5, 5'.

Claims (3)

PATENT CLAIMS Method for disconnecting a burner (5 ', 5, 5') with at least one supply line (3, 3 ', 3, 3') for a fuel gas / oxygen mixture, characterized by simultaneously interrupting the supply of fuel gas / oxygen mixture Oxygen to the burner (5 ', 5, 5') is supplied to the burner (5 ', 5, 5') with an inert gas or a gas (5 ', 5'). Flushing gas. Method according to claim 1, characterized in that, as an inert or resp. the purge gas is nitrogen or a gas mixture containing nitrogen, in particular air or compressed air. Device for carrying out the method according to any one of claims 1 to 2, comprising a plurality of burners (5 ', 5, 5') with at least one supply line (3 ', 3, 3') for the fuel gas / oxygen mixture, the supply lines (3 ', 3, 3') are provided with at least one control and / or shut-off valve (d ', d, d'), characterized in that in the supply lines (3 ', 3, 3 ') for the fuel gas / oxygen mixture flows downstream of the control and / or isolation valve (ï, d, ï') at least one supply line (4 ', 4, 4') for inert and resp. purging gas and supply lines (4 ', 4, 4') for inert and / or inert gas. the purge gas has at least one control and / or isolation valve (e ', e, e').