SE534008C2 - Procedure for operation of a gas turbine power plant and gas turbine power plant - Google Patents

Description

534 008 of the second group is shown to include a combustion device, which results in an arrangement in which the combustion gases from the combustion device have been given a radial component of movement at the entrance to the housing of the turbine. OBJECTS AND MOST IMPORTANT FEATURES OF THE INVENTION The background technology method works well but according to the present invention provides a further development focusing on increased economy, primarily with respect to the power plant itself and secondarily with respect to flexibility and simplicity regarding the arrangement of the second turbine group. .

These objects are addressed in accordance with the present invention.

When the combustion gas stream is produced in a coaxial combustion device and brought axially into the turbine of the second turbine group, the complexity of the plant and in particular the inlet to the second turbine device is reduced. It also allows the use of an uncomplicated combustion device that provides high performance in terms of temperature distribution and emissions.

Preferably uncomplicated, the invention also provides the freedom to make a combustion device without any particularly tight geometric constraints, which is otherwise the case when combustion devices must be designed to fit traditional gas turbines.

When the gas flow stream from the second turbine device is output between the second turbine device and the second compressor device, with substantially lower temperatures than from the combustion device output, the conditions become acceptable for uncomplicated long-term operation of the first turbine device. Temperature-influenced problems can thereby be reduced and geometric constraints avoided. 10 15 20 25 30 534 008 Possibilities increase to reach high temperature levels for efficiency improvement through an even temperature distribution due to the presence of high amounts of steam in the combustion device, and due to the advantageous IR distribution properties of steam. For example, the invention allows freer and more efficient selection of points and areas for steam and / or water injection. The combustion is made more harmonious in comparison with the situation in processes in accordance with the background technique.

Geometric solutions can be chosen more freely in terms of the design of an combustion chamber of the combustion device.

Overall, the process of the invention is made more economical to operate and components more economical to produce and maintain.

In previous gas turbine designs, the aim has been to create an incinerator that produces high temperatures and efficient temperature distribution inside and in gas emanating from the incinerator and to produce low emissions from the incinerator. This has often resulted in very complicated combustion device design, mainly due to geometric constraints resulting from the gas turbine structure itself. In particular due to the requirement for a central shaft for transferring mechanical work from the turbine to the compressor, there is a requirement for burner locations placed at a distance around the circumference of the turbine inlet. This has resulted in either an annular design or a design with multiple cans. Combustion devices for gas turbines in accordance with that background technique will thus surround the engine. Most disturbing has been the fact that the combustion device and the first stages of the turbine are the components that are most exposed to maintenance due to high temperatures and pressures. These components are expensive to maintain and replace due to their complexity. 534 008 It is preferred that process water and / or steam be injected into a gas flow stream whereby the necessary compression work can be reduced. In particular, water and / or steam are injected in such amounts that at least 60% of the oxygen content of the air in the gas flow stream is consumed by combustion.

When, in accordance with a preferred aspect of this invention, a first gas stream is compressed by a first compressor unit of the second compressor device, then brought to a heat exchanger for cooling said first gas stream and heating said process water and / or steam and then brought to a second compressor unit of said second compressor device, a natural and efficient possibility of intercooling the compressor air is provided, providing the possibility of improved flow geometry and pressure performance of the second compressor device.

Alternatively, water spray can be injected into the compressor flow between the first and second units of the second compressor device instead of inter-cooling through a heat exchanger. This can be achieved by, for example, extracting a gas flow to a separate water spray unit and returning it again.

The invention also relates to a power plant and corresponding features and advantages are obtained in relation to requirements directed towards this.

It is preferred that the combustion device is of the coaxial type, is a stand-alone combustion device and outside the engine and / or is a turbine-integrated axial combustion device. The second turbine group is separated from the main engine (the first turbine group) and gas is extracted between its turbine and its compressor. It has become practically possible in accordance with the invention to integrate arrangements with other turbine groups in new as well as already operational facilities in that the arrangement formed by the second turbine group is easy to install and to replace and maintain.

When said second compressor device has a first and a second compressor unit, it is especially preferred that the turbine of the second turbine group has a first and a second turbine unit, the first compressor unit being rotationally driven by the second turbine unit through a hollow first shaft and the second compressor unit being rotationally driven by the first turbine unit through a second shaft as this arrangement simplifies control and allows for simple independent control of the respective units. In particular, the first and second shafts should be coaxial with the first hollow shaft partially surrounding the second shaft.

Preferably, at least a part of the water content of the combustion gases is used as process feed water and / or process steam, which allows recovery with a certain excess, due to the formation of water during combustion.

Preferably steam is used for cooling the combustion gas stream, and at least a part of said steam is then introduced into the gas stream, preferably in the combustion device, for further use as working fluid.

As a definition, the gas flow enters the first compressor unit first and then the second compressor unit. The same applies to a gas turbine which has a first and a second turbine unit, whereby a gas flow enters the first turbine unit first and then the second turbine unit.

Said second compressor unit may also include additional compressor units in addition to the first and second compressor units.

The invention also relates to a top coil arrangement including a second turbine group. The term "top coil" here refers to a special compressor-turbine arrangement arranged 10 15 20 25 30 534 008 to supplement a main turbine group device by achieving more efficient operation.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to embodiments and with reference to the accompanying drawings, in which: Fig. 1 schematically shows a power plant according to the invention in a first embodiment, Fig. 2 schematically shows a power plant according to the invention in a second embodiment, and Fig. 3 schematically shows a power plant according to the invention in a third embodiment. Fig. 4 shows a detailed embodiment of a second turbine group with a shaft in an axial section, and Fig. 5 shows a detailed embodiment of a second turbine group with two shafts in an axial section.

DESCRIPTION OF EMBODIMENTS In the power plant according to the invention, the second gas turbine group operates in a temperature range where cooling is required and this can preferably be provided using steam. The steam can participate in this process in a very advantageous way by first cooling the high temperature components before it is introduced into the combustion device. In this way, this steam can also participate in the expansion process and provide additional work. However, part of the steam is used for film cooling of parts where convection cooling does not provide the necessary effect. This film cooling, where the steam acts as a protective layer between the gas stream and the metal, is very effective when steam is used due to the steam's higher heat capacity compared to air. 10 15 20 25 30 534 008 The first gas turbine group will work with conditions that do not require, or mainly, only require a limited amount of cooling. The spread of cooling air in a corresponding "dry" construction of such a gas turbine group can therefore be drastically reduced and instead allow a greater flow of working fluid in the turbine.

The optimal efficiency for a dry process, ie. for a traditional gas turbine cycle, is achieved at the relatively low pressure conditions of 5 - 40 bar. However, the optimum efficiency is at much higher pressure conditions for a steam-injected cycle. Consequently, it is important to increase the pressure ratio in steam-injected gas turbine cycles in order to reach the optimum operating conditions. A suitable pressure range for the power plant according to the invention is 30 - 300 bar and preferably 50 - 200 bar. Combustion temperature levels are between 1000 - 2200 ° K, preferably 1200 - 2000 ° K.

In some steam-injected bicycle configurations, the addition of water can be so great that combustion takes place at as close to stoichiometric conditions as is practically possible, ie. almost all the oxygen content in the air is used. This is one of the primary objects in the operation of the power plant according to the invention.

Combustion at near stoichiometric conditions leads to an efficient, compact and cost-effective power plant. The water that has participated in the process is not emitted to the environment but can be recycled through combustion gas condensation.

The condensate obtained can be treated continuously and recycled to the power cycle. The process of combustion gas condensation is simplified at near stoichiometric conditions due to the dew point being very high under such conditions and the cycle can be made water self-sufficient. Condensation of water from the combustion gases also helps to remove particles and, to some extent, contaminating substances from the combustion gases. Thus, the least possible environmental impact is achieved. Near stoichiometric combustion also implies that the flow of combustion gas to the environment is minimized.

Plant operation should be designed so that at least 60%, preferably at least 80% of preferably at least 90% of the oxygen content of the intake air is consumed. This represents a significant departure from the existing technology and provides the benefits outlined above.

The net result of introducing steam into the traditional gas turbine process is to increase the efficiency and production of useful work. Well-developed steam-injected gas turbine cycles operated at similar pressures and temperature levels as existing technology usually achieve efficiencies of approximately 50 - 55%. Steam-injected cycles operated at higher pressure levels receive efficiencies around 55 - 65% and useful work taken out will be 2 - 3 times higher than its corresponding conventional gas turbine process.

In order for the cycle to work efficiently and practically with pressure conditions required to reach 30 - 300 bar, at least two or for the highest pressure levels, three axles with different rotational speeds need to be used in the second compressor device of the second turbine group. The high pressure compressor and turbine would be operated at the higher rotational speed.

Thus, a multi-shaft solution would provide a conventional gas turbine device operating with one shaft, a second compressor device and turbine device operating on separate shafts rotating at higher speeds, and a combustion device operating at higher pressures and temperatures with near stoichiometric combustion. Steam and / or water can also be introduced by injecting high-pressure steam before the combustion chamber or by injecting medium-pressure steam and / or water before any of the compressor stages.

During operation at higher pressures, the need to cool the air between the compressor units increases; on the one hand to reduce the temperature level and material requirements in the compressor, and on the other hand to reduce the amount of necessary compressor work.

Lowering the temperature in the compressor air can also lead to more favorable conditions for combustion.

The easiest way to reach lower temperatures is to inject water into the compressed air stream. Alternatively, the heat content of the compressed air can be used to produce steam in a boiler.

Fig. 1 schematically shows a gas turbine power plant according to the invention, which includes a first 10 and a second gas turbine group. The first gas turbine group 10 includes a first turbine device 13, which is rotationally connected over a shaft 11 to a device 15 for taking out useful work, such as an electric generator or the like. The first gas turbine group 10 also includes a first compressor device 12, which is mechanically connected to the first turbine device 13.

The second gas turbine group 20 includes a second turbine device 23. The second gas turbine group 20 also includes a second compressor device 22. The second gas turbine group 20 further includes a device 25 for extracting useful work, which is an electric generator or the like.

Furthermore, an air cooler 74 in the form of a heat exchanger, which is used to produce steam for injection into the process, is positioned between the first and second compressor devices. After the outlet of the second compressor device 22, the air is led over a line 43 to the inlet of a combustion device 35, which is arranged axially upstream of the second turbine device 23, opposite to the compressor 22.

The combustion device 35 is coaxial and supplies combustion gases to an axial inlet of the second turbine device 23. Furthermore, there are inlets to the combustion device 35 for hot water 61 'and / or steam 61 for the purpose of providing a combustion process, wherein at least 60% of the oxygen content in the air in the flow stream is consumed by combustion in the combustion device 35. Fuel is supplied to the combustion device 35 via line 51.

The gases from the outlet of the turbine device 23 of the second turbine group flow through the line 48 to the turbine device 13 of the first turbine group.

The gases then exit the first turbine 13 and flow through line 49 to an additional heat exchanger 73, which contributes to the heating of steam for injection in the process through line 61.

After the heat exchanger 73, the combustion gases are passed through a heat exchanger 70, which contributes to heating water for injection into the process through line 61 'and whereby condensate from a combustion gas condenser 71 is heated before being led to a deaerator 72 over line 83.

Water is supplied to the heating circuit including the heat exchangers 73 and 74 via the deaerator 72, which has the purpose of ensuring that the water in the circuit is free of oxygen.

A certain amount of steam is led in a flow 63 through a line and is injected into the second turbine device 23 for film cooling. Additional steam used for further convention cooling inside the turbine blades is then extracted in a stream 68 through a line and fed into the combustion device to participate in the expansion process. Fig. 2 schematically shows a gas turbine power plant according to the invention, which differs from that in Fig. 1 in that the second gas turbine group 20 includes a second turbine device 23, which is constituted by a first turbine unit 23 'and a second turbine unit 23 ”. The second gas turbine group 20 also includes a second compressor device 22, which in turn consists of a first compressor unit 22 'and a second compressor unit 22'.

The first compressor unit 22 'is rotationally connected to the second turbine unit 23' over a first, hollow shaft 21 ', which partially surrounds a second shaft 21, which in turn rotationally connects the second compressor unit 22' to the first turbine unit 23 '. An air flow to inlet to the first compressor unit is indicated by 42 and after exiting the first compressor unit, the compressed air is led over a line 42 'to the inlet of the second compressor unit 22'. Furthermore, an air cooler 74 in the form of a heat exchanger, which is used to produce steam for injection into the process, is positioned between the first and second compressor units. As an alternative, the second gas turbine device may include three turbine units, each of which is rotationally connected to each of the three compressor units included in the compressor device. Three connecting shafts for the three respective steps are in that case coaxial corresponding to the two shaft alternative mentioned above.

After exiting the second compressor unit 22 ", the air is led over a line 43 to the inlet of a combustion device 35, which is arranged axially upstream of the first turbine opposite the compressor unit 22".

The combustion device 35 is coaxial and supplies combustion gases to an axial inlet to the first turbine unit 23 'of the second turbine device 23 and then to the inlet of the second turbine unit 23' of the second turbine device 23.

The first gas turbine group 10 in Fig. 2 includes a first turbine device 13, which is rotationally connected over a shaft 11 to a device 15 for taking out useful work such as an electric generator or the like. However, the second gas turbine group 20 does not include a device for taking out useful work, the other compressor and turbine devices being balanced to each other. The compressor device 12 of the first turbine group is relatively low-energy consuming and at least substantially all useful work produced by the plant is taken from the first turbine group. As a result, only the first turbine group needs to be connected to an electric generator or the like.

In this embodiment, steam passed through line 63 and injected into the second turbine device 23 for film cooling purposes is not subsequently taken out to be diverted into the combustion device.

Fig. 3 shows an embodiment which differs from that shown in Fig. 2 substantially in that all compressor work is produced in the second group, which gives more possibility for improved flow geometry with respect to the second turbine group. Another difference is that the steam generator 74 in the embodiment of Fig. 2 has been replaced by a spray intercooler 91.

Fig. 4 shows in more detail the second turbine group 20 in an axial cross section with a combustion device in the form of an axially oriented burner 35 connected to a turbine device 23.

The burner is fed with a mixture of fuel and air and also through steam and / or water for further control of the burner temperature.

The temperature of the combustion device 35 is intended to be about 1400 ° C, while the temperature downstream of the second turbine device 23 is about 1000 ° C, which is a level which is completely manageable for the transfer to and operation of the first turbine device 13 without any cooling requirements.

The second turbine device 23 is shown here to be cooled by a steam flow 63, which enters through a steam flow inlet 65, said steam stream 63 being initially injected into stationary parts and further transferred into rotating parts of the second turbine device 23. The steam flow 61 (see also figures 1 - 3) enters through one or both of the inlets 64 and 64 '. A stream of water 61 'enters by injection through an inlet 64' at a fuel injection end of a combustion chamber 66 directly into the combustion chamber 66 of the combustor 35. A vapor stream preferably cools the combustion chamber walls. This is the case, in this embodiment, for inlet 64 ', which leads to means for cooling the cladding. Reference 51 indicates fuel supply lines.

The second turbine group is of the shaft type and has an axial type turbine included in the second turbine device 23 and a radial type compressor included in the second compressor device 22, which are mechanically interconnected. A shaft 21 includes means 24 for connecting to a power take-off device.

The flow line 48 'transmitting the gas flow 48 from the second turbine device 23 to the first turbine device 13 is separated by compressed air flow 42 from the first compressor 12, inside a line 48 "in the arrangement shown in Fig. 4 before leaving the second turbine group 20. Reference 43 indicates a line for air flowing from the second compressor device 22 to the second turbine device 23 (see above).

A vapor stream 63 injected through an inlet 65 into the second turbine assembly 23 is used for both film cooling and conventional cooling. The corresponding used steam flow 68 is taken out through an outlet 65 '. It can then be fed into the combustion device through inlets 64 and / or 64 'to participate in the expansion process.

The embodiment in Fig. 5 differs from that in Fig. 4 mainly by presenting here, in more detail, a biaxial turbine group, from the plant which can be seen in Fig. 2 or 3.

The turbine-to-compressor coupling can be designed to be operated at higher pressure conditions and make the whole group possible to operate without any power take-off.

The second turbine device 23 has two single-stage high-pressure turbines. The second turbine assembly 23 consists of a first turbine unit 23 ', which is a single stage high pressure turbine and a second turbine unit 23 ", which is a single stage low pressure turbine. The second gas turbine group 20 also includes a second compressor device 22, which in turn consists of a first compressor unit 22 'and a second compressor unit 22'. The first turbine unit 23 'is supported by a bearing positioned in a central position by a hinge wall of the second turbine device and is driven by the shaft 21 (see also Fig. 2). The second turbine unit 23 ”is supported by a bearing positioned in the center of the guide rail of the second turbine stage and is driven through the shaft 21 '(see also Fig. 2).

Reference is made to the above with respect to the remaining reference numerals in Fig. 5. Vapor streams 63 injected only for film cooling are, after use, not subsequently taken out for supply to the combustion chamber. See Fig. 2.

The positioning of the burner coaxially to an adjacent turbine facilitates isolation of the burner from the main engine as well as from essential components in the second turbine group.

The temperature from the burner is intended to be about 1500 ° C, while the temperature downstream of the second turbine device is about 1000 ° C, which is a level which is completely manageable for the transfer to and operation of the first turbine device .

The invention can be modified within the scope of the claims.

For example, in some applications it is possible to include another low power consumer such as an auxiliary device, the first or the second turbine group. The embodiments in Figs. 2 and 3 can also be supplemented in this way. A device for extracting small amounts of useful work or the like can also in some applications be connected to the second turbine group also in the embodiments in Figs. 2 and 3.

It is also possible within the scope of the requirements to add overheating in addition to hot water and steam to the combustion gases and intermediate compressor flow path.

Claims (29)

10 15 20 25 30 534 008 16 P A T E N T K R A V A method of operating a gas turbine power plant having a first gas turbine group (10) including a first turbine device (13) and a second gas turbine group (20) including a second compressor device (22) and a second turbine device (23), which are mechanically connected to each other, and useful work is carried out by at least one device (15,25) included in a plant, wherein a combustion gas stream is produced by a combustion device (35), which is placed in a gas flow stream (42,48) upstream of the other the turbine device (23) and wherein process water and / or steam is heated by a process gas stream and the produced water and / or steam is injected into a gas flow stream (42,48) upstream of and / or in the combustion device (35) in such amounts that at least 60 % of the oxygen content in the air in the gas flow stream (42,48) is consumed by combustion and that the combustion gas fed to the second turbine device (23) has a pressure in the range of 50 - 300 bar, characterized in that the combustion gas stream is generated in a combustion device (35) coaxial with the second turbine device (23) and led axially into a side of the second turbine device (23) opposite to a side thereof closest to the second the compressor device (22), and that the gas flow stream (48) from the second turbine device (23) exits between the second turbine device (23) and the second compressor device (22). The method according to claim 1, characterized in that the pressure in the outlet of the second turbine device (23) is about 5 - 50 bar and most preferably between 10 - 30 bar. 10 15 20 25 30 534 008 17 The method according to claim 1 or 2, characterized in that the first gas turbine group (10) includes a first compressor device (12), which is mechanically connected to the first turbine device (13). The method according to any one of claims 1 to 3, characterized in that a first gas stream is compressed by a first compressor unit of said second compressor device (22), then brought to at least a second compressor unit of said second compressor device (22) . The method according to claim 4, characterized in that the first gas stream after the first compressor unit and before the second compressor unit is brought to a heat exchanger (74) for cooling said first gas stream and heating said process water and / or steam . The method according to claim 4, characterized in that the first gas stream after the first compressor unit and before the second compressor unit is brought to a spray unit for exposing the gas stream to a water and / or steam spray. The method according to any of the preceding claims, wherein said second compressor device (22) has a first and a second compressor unit, characterized in that the first turbine device has a first and a second turbine unit, the first compressor unit being rotationally driven of the second turbine unit over a first hollow shaft and the second compressor unit is rotationally driven by the first turbine unit over the second shaft. 10 15 20 25 30 534 008 18 The method according to any one of the preceding claims according to claim 4, wherein said second compressor device has a first and a second compressor unit, characterized in that the first gas flow after the second compressor unit of said second compressor device (22) is brought to at least one additional compressor unit of said second compressor device (22). The method according to claim 8, characterized in that each of said at least one further compressor unit (s) is driven by a corresponding turbine unit over a further shaft. The method according to claim 7 or 9, characterized in that the compressor units are driven by coaxial shafts, at least partially surrounding each other. The method according to any one of the preceding claims, characterized in that at least a part of the water content in combustion gases is used as process feed water and / or process steam. The method according to any one of the preceding claims, characterized in that steam is used for cooling combustion gases and that at least a part of said steam is subsequently introduced into the gas stream (42,48), preferably in the combustion device, for further use as a working fluid. Method according to any one of the preceding claims, characterized in that a flow line (48 ') transmitting a gas flow (48) from the second turbine device (23) to the first turbine device (13) is cooled by a compressed air. Flow (42), from the first compressor (12) inside a line (48 ") before leaving the second turbine group (20). A gas turbine power plant having a first gas turbine assembly (10) including a first turbine assembly (13) and a second gas turbine assembly (20) including a second compressor assembly (22) and a second turbine assembly (23), which are mechanically coupled to each other, and at least one of the first and second turbine groups (10,20) have a device (15,25) for taking out work, wherein a combustion device (35) for generating a combustion gas stream is placed in a gas flow stream (42,48) upstream of the second turbine device (23) and wherein heating means are arranged to heat process water and / or steam from a process gas stream and injection means are arranged to inject the generated water and / or steam into a gas flow stream (42, 48) upstream of and / or in the combustion device, characterized in that - a combustion device (35) for generating the combustion gas stream is coaxial with and positioned axially to the second turbine the device (23) on a side thereof opposite to a side closest to the second compressor device (22). and - that the outlet of the gas flow stream (48) from the second turbine device (23) is positioned between the second turbine device (23) and the second compressor device (22). The plant according to claim 14, characterized in that the coaxial combustion device (35) is one or more from the group: thin-type burners, a stand-alone burner set up outside the engine, a turbine-integrated axial burner. 10 15 20 25 30 534 008 20 The plant according to claim 14 or 15, characterized in that the second compressor device (22) includes a first and a second compressor unit (22 ', 22 "). The plant according to claim 16, characterized in that a heat exchanger (74) for cooling said first gas stream and heating said process water and / or steam is located after the first compressor unit (22 ') and before the second compressor unit (22 ”). The plant according to claim 16, characterized in that a spray unit for exposing the gas stream to a water and / or steam spray is located after the first compressor unit (22 ') and before the second compressor unit (22 "). The plant according to any one of claims 14 - 18, characterized in that the glass flow current outlet from the second turbine device (23) is between the second turbine device (23) and the second compressor device (22). The plant according to any one of claims 14 - 19, wherein said second compressor device (22) has a first and a second compressor unit (22 ', 22 "), characterized in that the second turbine device (23) has a first ( 23 ') and a second (23 ") turbine unit, the first compressor unit (22') being rotationally coupled to the second turbine unit (23") over a first, hollow shaft (21 ') and the second compressor unit (22 ") being rotationally coupled to the first turbine unit (23 ') over a second shaft (21). The plant according to claim 20, characterized in that the second turbine device (23) has more than two turbine units and that the second compressor unit has more than two compressor units. The plant according to claim 19 or 20, characterized in that the first and further shafts are coaxial and that the further shaft is at least partially surrounded by the first shaft. The plant according to any one of claims 14 to 22, characterized in that the first turbine group includes a first compressor device. A top coil arrangement for a gas turbine power plant having a first gas turbine group (10) including a first turbine device (13), said top coil arrangement including a second gas turbine group (20), in turn including a second compressor device (22) and a second turbine device (23), which are mechanically coupled to each other, wherein a combustion device (35) for generating a combustion gas stream is located in a gas flow stream (42, 48) upstream of the second turbine device (23), said plant including heating means are arranged to heat process water and / or steam from a process gas stream and injection means are arranged to inject the generated water and / or steam into a gas flow stream (42,48) upstream of and / or in the combustion device, and at least one of the first and second turbine groups (10,20) has a device (15,25) for taking out work, characterized by - a combustion device (35) for generating the combustion gas stream coaxial with and positioned axially to the second turbine device (23) on a side thereof opposite to a side closest to the second compressor device (22), and the outlet of the gas flow stream (48) from the second turbine device (23) is positioned between the second turbine device (23) and the second compressor device (22). The arrangement according to claim 24, characterized in that the coaxial combustion device (35) is one or more from the group: thin-type burners, a stand-alone burner and outside the engine, a turbine-integrated axial burner. The arrangement according to claim 24 or 25, characterized in that the second compressor device (22) includes a first and a second compressor unit (22 ', 22 "). The arrangement according to claim 26, characterized in that a heat exchanger (74) for cooling said first gas stream and heating said process water and / or steam is located after the first compressor unit (22 ') and before the second compressor unit (22 ”). The arrangement according to claim 26, characterized in that a spray unit for exposing the gas stream to a water and / or steam spray is located after the first compressor unit (22 ') and before the second compressor unit (22 "). The arrangement according to any one of claims 24 - 28, characterized in that the glass flow current outlet from the second turbine device (23) is between the second turbine device (23) and the second compressor device (22).