DE3430015C1

DE3430015C1 - Apparatus for burning hydrogen sulphide-containing gas to produce a process gas for the Claus process

Info

Publication number: DE3430015C1
Application number: DE19843430015
Authority: DE
Inventors: Herbert Dipl.-Ing. 6304 Lollar Fischer
Original assignee: Metallgesellschaft AG
Current assignee: MG Technologies AG
Priority date: 1984-08-16
Filing date: 1984-08-16
Publication date: 1986-05-07

Abstract

The process gas is generated in a furnace at temperatures from 1000 to 1300 DEG C. The furnace comprises an ancillary furnace whose combustion gases are passed into the furnace. Disposed on the furnace there is at least one burner lance whose mouth region has a central oxygen pipe, at least one H2S-gas pipe surrounding the oxygen pipe and an outer air pipe which is coaxial with the H2S-gas pipe. Formed on the furnace there is at least one ancillary combustion chamber which has feeders for steam, fuel gas and air. Adjacent to one ancillary combustion chamber there are arranged from 2 to 20 burner lances or more. The burner lances may be arranged, for example, on a circle surrounding the ancillary combustion chamber or on a plurality of circles. Some of the burner lances have two H2S-gas pipes, one of said H2S-gas pipes having a feed for recycled process gas.

Description

In die Brennkammer 1 mit ihrem ausgemauerten Gehäuse 2 münden gemäß F i g. 1 und 2 mehrere Brennerlanzen 3, 4, 30 und 31 sowie ein Stützfeuerungsraum 5. In the combustion chamber 1 with its brick-lined housing 2 open according to FIG. 1 and 2 several burner lances 3, 4, 30 and 31 as well as a support furnace 5.

Die Brennerlanzen sind in F i g. 1 und 2 nur schematisch dargestellt; sie bestehen im wesentlichen aus konzentrischen Rohren, wie weiter unten noch anhand der F i g. 3 erläutert wird.The burner lances are shown in FIG. 1 and 2 only shown schematically; they essentially consist of concentric tubes, as will be explained further below the F i g. 3 will be explained.

In der Brennkammer 1 wird H2S-haltiges Einsatzgas teilweise verbrannt, so daß ein Prozeßgas entsteht, in welchem das Mol-Verhältnis H2S : SO2 = 2 :1 beträgt. Feed gas containing H2S is partially burned in combustion chamber 1, so that a process gas is produced in which the molar ratio H2S: SO2 = 2: 1.

Dabei herrschen in der Brennkammer Temperaturen im Bereich von 1000 bis 1300°C.The temperatures in the combustion chamber are in the range of 1000 up to 1300 ° C.

In F i g. 1 sind zur Vereinfachung nur die Gaszuleitungen zur Brennerlanze 3 dargestellt; die Gasführung in der Brennerlanze 3 wird mit Hilfe der Fig. 3 erläutert. In Fig. 1, for the sake of simplicity, only the gas supply lines to the burner lance are shown 3 shown; the gas flow in the burner lance 3 is explained with the aid of FIG.

Durch die Leitung 7 führt man der Brennerlanze 3 technisch reinen Sauerstoff zu und durch das zentrale Sauerstoffrohr 8, vgl. F i g. 3, in die Brennkammer geleitet. Am Mündungsende des Sauerstoffrohrs 8 befindet sich ein Verdrängerkörper 9, durch den der ausströmende Sauerstoff nach außen geführt wird. Koaxial zum Sauerstoffrohr 8 ist das erste H2S-Gas-Rohr 10 angeordnet, das von außen, vgl. Fig. 1, mit H2S-haltigem Einsatzgas aus der Leitung 11 und durch das geöffnete Regelventil 12 und die Leitung 13 angeströmt wird. Ein Überschuß an H2S-haltigem Einsatzgas strömt durch die Zweigleitung Ila, das Regelventil 14 und die Leitung 15 sowie durch das zweite H2S-Gas-Rohr 16. Wie aus F i g. 3 zu ersehen ist, umgibt das zweite H2S-Gas-Rohr 16 das erste Rohr 10 koaxial. Das äußerste Rohr, vgl. Fig. 3, ist das Luftrohr 18, es führt zwischen sich und der Außenseite des zweiten H2S-Gas-Rohres 16 Luft, die in der Leitung 19 herangeführt wird. Das Luftrohr 18 ist am Mündungsende 18a etwas nach innen eingezogen, um eine gute Durchmischung der Luft mit dem H2-haltigen Einsatzgas aus den Rohren 10 und 16 zu erreichen.The burner lance 3 is technically pure through the line 7 Oxygen to and through the central oxygen tube 8, see FIG. 3, into the combustion chamber directed. At the mouth end of the oxygen tube 8 there is a displacement body 9, through which the outflowing oxygen is led to the outside. Coaxial to the oxygen tube 8 the first H2S gas pipe 10 is arranged, which from the outside, see FIG. 1, with H2S-containing Feed gas from line 11 and through the open control valve 12 and the line 13 is flowed against. An excess of feed gas containing H2S flows through the branch line Ila, the control valve 14 and the line 15 as well as through the second H2S gas pipe 16. As shown in FIG. 3, the second H2S gas pipe 16 surrounds the first pipe 10 coaxial. The outermost tube, see Fig. 3, is the air tube 18, it leads between and the outside of the second H2S gas pipe 16 is air that is in the line 19 is introduced. The air tube 18 is drawn in slightly inwards at the mouth end 18a, a thorough mixing of the air with the H2-containing feed gas from the pipes 10 and 16 to reach.

Durch das zweite H2S-Gas-Rohr 16 kann auch noch rückgeführles Prozeßgas aus der Leitung 20, vgl. Fig. 1, geführt werden, in der Leitung 20 befindet sich das Regelventil 21. An Stelle von Prozeßgas kann auch bereits weitgehend entschwefeltes Abgas aus einer Claus-Anlage verwendet werden, wobei es sich empfiehlt, dieses Abgas mit Temperaturen von etwa 200 bis 400"C durch den Gasraum des zweiten H2S-Gas-Rohres 16 zu leiten, damit auch dann keinen Ansätze auftreten, wenn aus der Leitung 11 a kein oder nur wenig H2S-haltiges Gas zugemischt wird. Im Unterschied zum zweiten H2S-Gas-Rohr 16 wird das erste H2S-Gas-Rohr 10 stets mit H2S-haltigem Einsatzgas aus den Leitungen 11 und 13 durchströmt. Um auch bei kleiner Menge an der Brennerlanze zugeführtem Schwefelwasserstoff noch genügend hohe Verbrennungstemperaturen zu erreichen, kann die Verbrennung mit technisch reinem Sauerstoff aus der Leitung 7 und dem Sauerstoffrohr 8 betrieben werden. Die Sauerstoffzufuhr durch die Leitung 7 kann vermindert oder abgestellt werden, wenn Luft aus der Leitung 19 einen für die Verbrennung ausreichend hohen Sauerstoffgehalt liefert. Recirculated process gas can also be fed through the second H2S gas pipe 16 from the line 20, see. Fig. 1, in the line 20 is located the control valve 21. Instead of process gas, material that has already been largely desulphurized can also be used Exhaust gas from a Claus plant can be used, it being advisable to use this exhaust gas with temperatures of about 200 to 400 "C through the gas space of the second H2S gas pipe 16, so that no approaches occur even if from the line 11 a little or no gas containing H2S is added. In contrast to the second H2S gas pipe 16 is always the first H2S gas pipe 10 with feed gas containing H2S flows through the lines 11 and 13. Even with a small amount on the burner lance the supplied hydrogen sulfide can still reach sufficiently high combustion temperatures, can combustion with technically pure oxygen from line 7 and the oxygen tube 8 can be operated. The oxygen supply through line 7 can be reduced or be turned off when air from line 19 is sufficient for combustion provides high oxygen content.

In den Stützfeuerungsraum 5 mündet ein zentrales Rohr 25 für Wasserdampf, das von einem Rohr 26 für die Einspeisung von Heizgas umgeben ist. Luft wird im äußeren Rohr 27 herangeführt. Dadurch, daß die Stützfeuerung nicht nur mit Heizgas und Luft, sondern auch noch mit Wasserdampf beschickt wird, erreicht man im Feuerungsraum 5 eine rußfreie Verbrennung auch bei unterstöchiometrischer Luftzufuhr. Durch die Verbrennungsgase der Stützfeuerung, deren Temperatur im Bereich von 1200 bis 1600"C liegt, sorgt man dafür, daß in der Brennkammer eine Temperatur-Untergrenze, die üblicherweise bei 1000°C liegt, nicht unterschritten wird. A central pipe 25 for water vapor opens into the support furnace 5, which is surrounded by a pipe 26 for the supply of heating gas. Air is in outer tube 27 brought up. The fact that the auxiliary firing is not only with heating gas and air, but also with water vapor, can be reached in the furnace 5 soot-free combustion even with a substoichiometric air supply. Through the Combustion gases from the auxiliary furnace, the temperature of which is in the range from 1200 to 1600 "C is, one ensures that in the combustion chamber a lower temperature limit, the usually is at 1000 ° C, is not fallen below.

In eine Brennkammer 1 kann eine unterschiedliche, stark variierende Anzahl von Brennerlanzen 3,4,30,31 münden. Wie F i g. 2 zeigt, sind die Brennerlanzen auf einem Kreis um den Stützfeuerungsraum 5 herum angeordnet. Einzelne Brennerlanzen 3 können die in F i g. 1 und 3 wiedergegebene Ausgestaltung mit zwei H2S-Gas-Rohren 10 und 16 aufweisen. Es ist aber auch möglich, eine, wenige oder eine größere Anzahl der Brennerlanzen einer Brennerkammer 1 nur mit einem H2S-Rohr auszurüsten und dabei auf die Leitungen 11a und 15 und eine Zuleitung 20 für zurückgeführtes Prozeßgas zu verzichten. Im Gegensatz zum Mündungsende der Brennerlanze der F i g. 3 weist eine solche vereinfachte Brennerlanze nur drei konzentrische Rohre, nämlich für Sauerstoff, H2S-haltiges Einsatzgas und Luft, auf. Es ist z. B. möglich, in der Darstellung der F i g. 1 und 2 die Brennerlanzen 3 und 4 mit zwei H2S-Gas-Rohren 10 und 16 auszurüsten und versetzt davon zwei Brennerlanzen 30 und 31 anzuordnen, die nur jeweils ein H2S-Gas-Rohr enthalten. Die vereinfachten Brennerlanzen 30 und 31 dienen zum Betrieb des Brenners im Lastbereich der Anlage über 25%, wogegen die Brennerlanzen 3 und 4 auch für die Einspeisung kleiner Mengen an H2S-haltigem Einsatzgas in die Brennkammer 1 geeignet sind. Abweichend von F i g. 2 kann man die Anzahl der Brennerlanzen vom Typ der Brennerlanze 3 gegenüber der Anzahl der vereinfachten Brennerlanzen 30, 31 beliebig variieren, auch die gegenseitige Anordnung ist frei wählbar, weil jede Lanze zusammen mit der Stützfeuerung in der Lage ist, das gewünschte Prozeßgas zu erzeugen. Alle Brennerlanzen sind so ausgerüstet, daß sowohl mit Luft, mit Luft und Sauerstoff und auch nur mit reinem Sauerstoff gefahren werden kann, ohne daß eine Betriebsunterbrechung notwendig ist. In a combustion chamber 1 can be a different, strongly varying Number of burner lances 3,4,30,31 open. Like F i g. 2 shows are the burner lances arranged on a circle around the support firing chamber 5. Individual burner lances 3, the in F i g. 1 and 3 shown embodiment with two H2S gas pipes 10 and 16 have. But it is also possible to have one, a few or a larger number to equip the burner lances of a burner chamber 1 only with an H2S tube and thereby to lines 11a and 15 and a feed line 20 for recycled process gas to renounce. In contrast to the mouth end of the burner lance of FIG. 3 points such a simplified burner lance only three concentric tubes, namely for Oxygen, feed gas containing H2S and air. It is Z. B. possible in the Representation of the F i g. 1 and 2 the burner lances 3 and 4 with two H2S gas tubes 10 and 16 and to arrange two burner lances 30 and 31 offset from them, each containing only one H2S gas pipe. The simplified burner lances 30 and 31 are used to operate the burner in the load range of the system over 25%, whereas the Burner lances 3 and 4 also for feeding in small amounts of feed gas containing H2S in the combustion chamber 1 are suitable. Notwithstanding FIG. 2 you can get the number of the burner lances of the burner lance type 3 compared to the number of simplified ones The burner lances 30, 31 can be varied as desired, and the mutual arrangement is also free can be selected because each lance, together with the auxiliary firing system, is capable of producing the desired Generate process gas. All burner lances are equipped in such a way that both air, can be driven with air and oxygen and also only with pure oxygen, without an interruption of operation is necessary.

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Claims

Claims: 1. Device for burning hydrogen sulfide containing Gas for generating a process gas containing hydrogen sulfide and sulfur dioxide for the Claus process, with a combustion chamber for generating the process gas Temperatures from 1000 to 1300 "C, with air and H2S-containing gas inlets to the combustion chamber and with a supporting firing in one opening into the combustion chamber Support firing room, with the combustion gases of the support firing in the combustion chamber and the auxiliary firing feed lines for hydrocarbon-rich heating gas and air, characterized in that at least a burner lance (3, 4, 30, 31) is arranged, the mouth area of which has a central Oxygen tube (8) at least one H2S gas tube (10) surrounding the oxygen tube and an outer air pipe (18) coaxial with the H2S gas pipe, and that on the Combustion chamber at a distance from the burner lance (3, 4, 30, 31) at least one supporting combustion chamber (5) is formed, which has supply lines for water vapor, heating gas and air.

2. Apparatus according to claim 1, characterized in that one Support firing space adjacent. 2 to 20 burner lances or more are arranged.

3. Apparatus according to claim 2, characterized in that the burner lances for example on a circle surrounding the support furnace or on several circles are arranged.

4. Apparatus according to claim 1 or one of the following, characterized characterized in that the combustion chamber includes at least one burner lance, the two Has H2S gas pipes and one of these H2S gas pipes has a feed for returned Process gas heard.

5. Apparatus according to claim 1 or one of the following, characterized characterized in that the mouth of the oxygen tube of the burner lance one the Has gas flow dividing displacement body.

The invention relates to a device for burning hydrogen sulphide Gas for generating a process gas containing hydrogen sulfide and sulfur dioxide for the Claus process, with a combustion chamber for generating the process gas Temperatures from 1000 to 1300 "C, with air and H2S-containing gas inlets to the combustion chamber and with a supporting firing in one opening into the combustion chamber Support firing room, with the combustion gases of the support firing in the combustion chamber and the auxiliary firing feed lines for hydrocarbon-rich heating gas and has air. Such a device is known from US Pat. No. 3,860,697.

In the Claus process, the feed gas containing hydrogen sulfide is used first converted to a mixture of H2S and SO2 by partial combustion, a molar ratio of the two components of 2: 1 is aimed for. This Gas mixture, here as Process gas is referred to, is then passed through a catalytic Claus plant, in which 2 H2S + SO2 to elemental sulfur and water being transformed. In this catalysis, for. B.

Al2O3 catalysts are used. The exhaust of the catalytic Implementation is given to a desulfurization plant, and the sulfur compounds the exhaust gas from the desulphurisation system is usually converted into a thermal one Afterburning to SO2, so that an exhaust gas is produced, albeit only a small one Contains amounts of SO2. A detailed description of the Claus process can be found in Ullmanns Enzyklopadie der Technischen Chemie, 4th Edition (1982), Vol. 21, pages 8 to 26.

The invention is based on the object of the burner device to design for the generation of the process gas that their feed gas with strong abandoned fluctuating H2S content and also a strongly fluctuating amount of feed gas can be. According to the invention, this takes place in the device mentioned at the beginning in that at least one burner lance is arranged on the combustion chamber, the Muzzle area a central oxygen tube, at least one the oxygen tube has surrounding H2S gas pipe and an outer air pipe coaxial with the H2S gas pipe, and that on the combustion chamber at a distance from the burner lance at least one support furnace space is designed, which has supply lines for water vapor, heating gas and air.

The support firing ensures that both in the start-up phase as well with little addition of hydrogen sulfide, which is the actual fuel is to maintain the necessary temperatures in the combustion chamber. The burner lance can deliver the necessary oxygen both through the air tube and through the central Obtain oxygen tube. The arrangement of the pipes ensures that a Combustion already in the burner lance or directly at the mouth end of the lance is avoided, which could lead to harmful high temperatures for the lance.

It is advisable to have 2 to 20 burner lances adjacent to a support furnace or more to assign.

The burner lances can be on a surrounding the support furnace Circle or be arranged on several concentric circles.

In order to further increase the flexibility of the burner device, opens in the combustion chamber at least one burner lance, which has 2 H2S gas tubes, wherein one of these H2S gas pipes has a feed for recycled process gas. Here you give the one H2S gas pipe about 5 to 20% of that for the burner lance maximum permissible amount of H2S-containing feed gas and passes through the second H2S gas pipe the remaining feed gas containing H2S, possibly together with the recycled Process gas. This second H2S gas pipe can only be given process gas in order to to keep it free from deposits by constant rinsing.

Design options for the burner device are made with the help the drawing explained. It shows F i g. 1 shows a simplified longitudinal section the burner device, F i g. 2 in a reduced representation a section according to the line II-II in F i g. 1 and 3 show a longitudinal section through the mouth area a burner lance with two H2S gas pipes in an enlarged view.