DD160904A1 - METHOD FOR OPERATING RELAXATION TURBINE COMPRESSORS WITH RESERVE PACK FOR GAS COMPRESSION - Google Patents

Abstract

The method relates to a one-stage and multi-stage operation of expansion turbine compressor systems with reserve unit for compression and pressure reduction of gas streams of different pressure levels on Eardgasfeldern and Ferngasastransportsystem. The aim of the invention is to reduce the number of reserve units and the equipment costs. According to the invention, the reserve unit (s) are arranged in series with the working machines, and when switching from working to reserve machine, this does not always occur in place of the out of service machine, but ensures that the same number of machines are in operation is. The reserve machine (s) can be operated as an additional stage (s).

Description

Method of driving expansion-turbine compressor nozzles with gas compression backup unit _i;

Field of application of the invention

The invention relates to a method for one-stage and multi-stage operation of expansion turbine-compressor systems, in particular with reserve unit (s) for compression and expansion of gas streams of different pressure levels on natural gas fields and in the remote gas transport system.

Characteristic of the known technical solutions

Bs is known and customary for reasons of operational and supply security in compression of gases, especially on natural gas fields and Ferngastransportsystem, regardless of the type of drive the machine in each compression stage to provide at least one closable shutoff to the main engine by valves compressor, which in case of failure of the main engine is put into operation. In most cases, due to the variable amount of gas to be compressed, several compressors including reserve compressors shut off parallel between a suction and a Drucksammeischiene arranged similar circuits with backup unit are in the previous known single-stage use of unburned connected expansion turbines directly coupled with compressors utilizing the adiabatic relaxation customary for cryogenic production in cryogenic separation plants.

These methods and Prozeßschaltungeh adheres to the disadvantage that in single and multi-stage compression in each stage a separate reserve unit in parallel or a reserve unit for all stages, which is connected in parallel in the respective stage is provided. The reserve unit can not be connected as an additional level. ' In any case, high investment and investment costs arise.

Aim of, invention

The aim of the invention is to increase the effectiveness and reliability of a gas compression with expansion turbine compressor units and to reduce the cost of equipment.

Presentation ; the essence of the invention

The invention has for its object to develop a method in which for a η-stage overall system of unburned Bts turbines using the technical work capacity of a high pressure gas stream with directly coupled compressors for compressing a gas stream only one or, with increased demands on the security of supply maximum n-1 reserve units, which can still be used as an additional stage.

Brfindungsgemäß the object is achieved in that the or the reserve unit (s) is arranged in one or more stages of driving in series (are). All power-turbine compressor aggregates in the individual stages, including the reserve engine (s), are designed for equal compression ratios and have the same fittings-like equipment, with each

and on the outlet side to the turbines and compressors and in the bypass to this one provided with an actuator on-to-valve is arranged.

By this design and process circuit is given the option, depending on the required reliability one or both external units as reserve machines. If necessary, they can also be put into operation as additional stages.

Furthermore, one or more valves connected in parallel to the turbines and compressors are arranged parallel to the turbines and compressors for startup and shutdown operation as well as for load shedding when the speed is exceeded. "The function of the startup and shutdown armatures and the opening armature for load shedding in case of overspeed can be taken over by a valve if their technical parameters meet the requirement for continuous slow closing characteristics and short-term opening.

The changeover from main to reserve machine is carried out by control measures of start-up valves and on-off valves of each machine according to program, the reserve unit in multi-stage driving does not always take the place of the failed unit, but only ensures that the same number of machines in operation. The stationary machine is shut off and bypassed by the open bypass valve. «All expansion turbine compressor units are similar to a safety circuit for load shedding in case of overspeeding for applying the on / off valves in parallel with the start and stop valves in the total bypasses fitted,

Ausführunfisbeispiel

The invention will be explained in more detail below with reference to an embodiment for a two-stage driving with a reserve unit.

The expansion-turbine compressor units (1a, b) and (2a, b) represent the main engines and the unit (3a, b) the reserve engine. It is also possible that the units (2a, b) and Oajb) the Main and the aggregate (1a, b) represent the reserve machine. In the diagram, the quantity and pressure controls required for a constant pairwise operation in the line (8) are not included · For technical reasons, the speed-safety circuit SAH for load shedding was only shown on the machine (1a, b). All machines are equipped the same »

In normal operation with aggregate (3 &, b) as a reserve engine, the high pressure gas flows through the Bunt turbines (2b) and (1b) and is relaxed while using the low pressure gas of the line (6) in the compressors (1a) and (b) 2a) is compressed to the Fortleitungsdruck in the line (7). In this procedure, the valves (3c, d, f, g) of the reserve unit (3a »b) are closed and the associated bypass fittings (3e, h) are opened, while the valves (1c, d, f, g) and ( 2c "d, f, g) are opened and the bypass fittings (1e, h) and (2e, h) of the main machine (1a, b, 2a, b) are closed.

Also closed are the fittings (4a, b, 5a, b) of the total bypasses across the compressors and turbines. From the Prozseßschema is readily apparent that with appropriate dashboard switching the following modes are possible?

- Single-stage operation of each unit, with the other two units serving as reserve machines

- Two-stage driving with the units (la, b) or (3a, b) as reserve machine and the other two units as the main engine

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- Three-stage operation of all units (1a, b, 2a, b, 3a, b) without reserve machine.

The application is not limited to the example, but can be used in particular but in η-stage driving. In each Pail either one or both outer aggregates of the connected system can serve as reserve machines.

Claims (2)

invention claim 1. A process for single and multi-stage operation of expansion turbine compressor systems, in particular with reserve unit (s) for compression and expansion of gas flows of different pressure levels on the required propagation pressures on natural gas fields and Ferngastransportsystem under combustion-free utilization of the technical work capacity of a high pressure gas stream, characterized in that the or, the reserve unit (s) is arranged in series with the working machine (s) and when switching from working reserve machine, this does not always occur instead of the out of service machine, but is only guaranteed in that the same number of machines is in operation. 2 «Procedure after, period. 1, characterized in that at η-stage driving for the entire system only one or, with increased demands on the security of supply maximum n-1 reserve unit (s) are provided. 3 «method according to point _L 1 and 2, characterized in that the reserve machine (s) can be operated as an additional stage (can). 4. The method according to < point, 1 to 3, characterized in that all expansion turbine Verdiohter aggregates in the individual stages including the (the) reserve machine (s) are designed for equal expansion and compression ratios » 5 · process circuit diagram for carrying out the method according to the invention by point. 1 to 4, daöurch characterized in that all expansion turbine compressor units including reserve machine (s) on the input side and output to the turbines and compressors and in the bypass to these - "7 - equipped with ffiotor-operated on-off valves and in the bypasses over the entire plant turbines «- and compressor side with one or more parallel valves for startup and shutdown as well as the load shedding in case of overspeed. For this 1 page drawings