JPS61187539A - Gas turbine equipped with shaft driven fuel gas compressor - Google Patents

Abstract

PURPOSE:To avoid the necessity of a driving means exclusively used for a combustion-gas compressor system equipment and cut cost by utilizing the gas-turbine driving power as the driving power for the system equipment, in a system equipped with a gas turbine and a fuel gas compressor. CONSTITUTION:The fuel supplied from a low-pressure fuel gas taking-in port 1 is compressed by a fuel gas compressor 5, and supplied into a combustor 30 through a separator 37, precooler 38, snapper 40, and a manifold 44. Under the supply of the discharge air from a compressor 28, said fuel gas is combusted in the combustor 30, and the high-temperature and high-pressure combustion gas generated is supplied into a gas turbine 29 to carry-out work, and said gas drives a power generator 31. In the above, the system equipment consisting of a fuel-gas compressor 5, lubricating-oil pump 9, cooling-water pump 10, etc. is driven by the driving power of the gas turbine through an auxiliary driving gear mechanism 32.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a system that includes a gas turbine and a fuel gas compressor.

[Background of the invention]

In a conventional gas-fired gas turbine system, the fuel gas supply system is the basic system of the gas turbine, i.e.
It was a mechanically independent system from the lubricating oil, cooling water, and seal air systems. FIG. 7 shows an example of a conventional fuel gas supply system. A fuel gas compressor system 3 is installed to boost the pressure of the fuel gas supplied from the low pressure fuel gas connection 1 to a predetermined pressure required at the gas turbine fuel gas connection point 2.

In the fuel gas compressor system, the gas line is connected to the compressor 5. for boosting pressure. Bypass valve for no-load operation while waiting for startup 15. Radiator to cool compressor outlet gas6. It consists of control valves 13 and 14 for adjusting the output log gas pressure. 19,20.2
], , 22 are control air systems for controlling the control valves 13 and 14, respectively showing a control air line, a bebicon, a bebicon electric motor, and a pressure regulating valve.

In the figure, 7 and 8 are compressor electric motors, respectively.
Although this is a radiator fan electric motor, other motors may be used. This gas compressor system includes a lubricant pump 9 for lubricating the frame and cylinders. The lubricating oil system consisting of the motor 11 and other equipment, il■
There is a cooling water system consisting of a cooling water pump 10°, an electric motor 12, etc. for cooling the oil and the compressor cylinder.

In the conventional system shown in FIG. 7, the gas turbine body,
The gas compressor is operated independently of the gas turbine system, which consists of a lubricating oil system, a cooling and sealing air system, and a (downstream) fuel gas line after a predetermined fuel gas pressure is achieved.

That is, the electric motors 7, 8, 11.12 are started by the gas compressor start command, and the control valve 13.1 is activated.
The gas turbine can only be started after the gas compressor system 4 operates and a predetermined gas pressure is obtained, but the gas compressor system 3 itself is not mechanically connected to the gas turbine, so it is an independent system from the gas turbine. It has become. This indicates that a lubricating oil system and a cooling water system are dually present in the gas turbine and fuel gas compressor.

Gas turbines operate from startup until they fail to meet their rated load.

Although fuel consumption fluctuates widely (approximately 5% to 100%),
In an independent gas compressor system, the parent-child valve control system shown in FIG. 1 is often adopted because - number of control valves 13 cannot be used. FIG. 8 shows a schematic diagram of parent-child valve control. The horizontal axis is the Cv value indicating the flow rate characteristics of the valve,
The vertical axis is the pressure signal from the pressure instruction controller 16. In the figure, 23 and 24 are child valves 14 and 24, respectively. The solid lines 25 and 26 show the individual valve characteristics of the master valve 13, and the solid lines 25 and 26 are the master valve.

This is the flow rate characteristic of the child valve, and as a control valve system, it is controlled as 25°26 according to the pressure signal (the valve opening degree is adjusted). At this time, the parent valve opens and the valve enters water for the first time, passing through a transition point 27 where the characteristics of the valve change rapidly.At such a transition point, the parent valve and child valve interfere with each other, which is called hunting. Because of the existence of unstable phenomena, -qi must pass. That is, during design, care must be taken to ensure that the flow rate at the transition point 27 does not match the fuel flow rate for ignition, warm-up, acceleration, etc. of the gas turbine.

That is, since the conventional gas compressor is a system independent of the gas turbine, (1) the compressor system is installed separately from the gas turbine and takes up a large space.

(2) The lubricating oil system, cooling water system, control air system, etc. are independent from the gas turbine system, and there is a waste in that the same systems exist for the gas turbine and gas compressor.

(3) Flow rate control is complicated.

(4) (1), (2), and (3) incur enormous costs.

On the other hand, there is a mature technology called atomizing air systems in liquid fuel fired gas turbines.

FIG. 9 shows an example of an atomizing air system. A portion of the air discharged from the compressor 28 is sent to the atomizing air system 36 to help atomize the fuel in the combustor and maintain good combustion conditions.
used as. Compressor discharge air is filtered by a separator 37 and heat exchanged by a precooler 38. 39 is a part of the cooling water system of the gas turbine, and the precooler outlet spray air temperature is controlled by adjusting the water amount with a temperature control valve 43. The atomized air exiting the precooler is pressurized by an atomized air compressor 35 attached to an accessory drive gear. The pressurized atomizing air system is atomized into the combustor through an anti-pulsation snapper and manifold.

[Purpose of the invention]

The object of the present invention is to solve the above problems by integrating a compressor into a gas turbine system from the beginning.

[Summary of the invention]

A gas compressor requires a gas compressor main body, a lubricating oil pump, a cooling water pump, etc., and conventionally, electric motors, engines, etc. have been used as motive power for these. By using gas turbine shaft power for these driving forces, it is possible to make a system that combines a gas turbine and a gas compressor very compact.

[Embodiments of the invention]

FIG. 1 shows an example of a system that uses gas turbine shaft power as gas compressor auxiliary power.

Fuel gas compressor5. Lubricating oil pump9. The cooling water pump 10 is characterized in that it is driven by gas turbine shaft power via an auxiliary drive gear 32. As can be seen from the figure, the fuel gas line is an atomizing air system (FIG. 9) in an oil-fired gas turbine provided with a bypass line consisting of a bypass control valve 45 and a check valve 46.

Since an atomizing air system is not required in a gas-fired gas turbine, a gas turbine system with a shaft-driven fuel gas compressor can be established with only some modifications to the currently established technology atomizing air system. Fuel supplied from the low-pressure fuel gas connection 1 is pressurized by a fuel gas compressor 5 driven by an auxiliary drive gear. The pressurized fuel gas passes through the separator and is cooled by the precooler 38. The cooled fuel gas is led to the combustor through the snubber and manifold. The bypass control valve 45, in which the fuel flow rate is controlled by bypassing the compressed fuel gas to the compressor suction side, is controlled by control air and fuel control signals, but at startup when fuel consumption is low.

Since the rotation speed of the accessory drive gear shaft is low, the pressure and therefore the flow rate of the fuel discharged from the compressor is low, and the amount of bypass returned to the compressor suction side through the bypass control valve 45 is also small. In the independent gas compressor system shown in Figure 7, the fuel gas pressure is constant regardless of the operating state of the gas turbine, so fuel consumption is high at startup (at this time, the amount of bypass is large) and when the fuel consumption is low. The range of the bypass amount at rated load (at this time the bypass amount is small) is large and cannot be controlled with a single valve, forcing complicated parent-child valve control. By adopting a gas compressor system, it can be controlled by - bypass control valves.

The high-pressure fuel gas line is equipped with a safety valve 47, which greatly improves reliability because it requires simple control and eliminates concerns about hunting.It releases fuel gas to the suction side (low-pressure side) to prevent abnormal pressure rise. prevent. At the time of emergency stop of the gas turbine, the fuel gas compressor clutch 48 is disengaged and fuel supply is stopped.

FIG. 2 shows an example of a lubricating oil and cooling water system in a conventional gas compressor system. The lubricating oil stored in the frame 56 is supplied to the cross guide 50 through the oil cooler 52 by the lubricating oil and lubrication assist electric motor 54 . In addition, the electric motor 54 also drives a lubricating machine 55.
Lubricating oil is sent to the rod packing and cylinder. On the other hand, the cooling water cooled by the radiator 6 is supplied to the oil cooler 52 and the cylinder 49 by the cooling water pump 10.

FIG. 3 shows an example of a conventional gas turbine lubricating oil system. The lubricating oil stored in the lubricating oil tank 69 is pumped to the gas turbine bearing 65 by the main lubricating oil pump 60 driven by the gas turbine shaft power via the auxiliary drive gear 32. Couplings 64, 66, reducer 67,
The oil is sent to the atomizing air compressor 35 via the generator 68 and the auxiliary drive gear. The amount of oil sent to each part is controlled by keeping the pressure in the lubricating oil header 73 constant with a pressure regulating valve 61. It also assists when starting and stopping the gas turbine at low rotational speeds, and in emergencies.

An emergency pump 72 is provided.

FIG. 10 shows an example of a lubricating oil system when a shaft-driven fuel gas compressor is employed. As can be seen from the figure, a lubricating oil system for a gas turbine or a gas compressor can be created by simply converting the atomizing air compressor into a fuel gas compressor in the conventional gas turbine lubricating oil system. By integrating the system, a lubricating oil tank for the gas compressor (the frame 56 also served), an electric motor 54 for the lubricating oil and lubrication machine, which was necessary when the system was unique to the gas compressor. The oil cooler 52 etc. can be deleted. By integrating the system, the number of required equipment is reduced, the system is compact, reliability is greatly improved, and costs are significantly reduced.

FIG. 4 shows an example of a conventional gas turbine cooling water system.

The cooling water filled in the cooling water tank 74 is returned to the cooling water tank through the oil cooler 52 and the radiator 6 by the cooling water pump 10 driven by the gas turbine shaft power via the accessory drive gear 32. The lubricating oil temperature is controlled by adjusting the opening degree of the temperature regulating valve 75 using a temperature sensor 76 attached to the lubricating oil ladder 73 and adjusting the amount of cooling water passing through the oil cooler. The cooling water that has passed through the oil cooler and the cooling water that has bypassed the oil cooler meet at the cooler outlet, but are separated again into a line that passes through the pre-cooler 38 and a line 81 that bypasses the pre-cooler. The temperature of the atomizing air is sensed by a temperature sensor 82 provided in the atomizing air line 83, and is controlled by adjusting the amount of cooling water passing through the precooler with a temperature regulating valve 43.

After that, the combined cooling water passes through the radiator in line 7.
9 and a line 80 that bypasses the radiator. Cooling water temperature is controlled by a radiator bypass control valve 78.

FIG. 5 shows an example of a cooling water system when a shaft-driven fuel gas compressor is adopted.

As can be seen from the figure, this system is a conventional cooling water system for a gas turbine, but only changes the temperature sensor to the fuel gas. By integrating the cooling water system and cooling the fuel gas with water, the radiator fan motor 8
It becomes possible to delete. Also, the cooling water tank for the gas compressor can be removed.

FIG. 6 shows an example of a system using compressor discharge air as fuel gas flow rate control air. A portion of the compressor discharge air passes through the pressure reducing valve 85 and is guided to the positioner of the fuel gas bypass control valve 45. Since the control air needs to be at a low pressure, the compressor discharge air pressure is sufficient even when the gas turbine is started at a low rotational speed.On the other hand, at rated speed, the pressure is too high, so the pressure is reduced by the pressure reducing valve 85 and the control valve is closed. 4 to 45. By adopting this system, the bebicon 20 shown in Fig. 7 becomes unnecessary, and in addition to the cost,
Reliability is improved.

In the figure, 4 is a gas turbine system, 16 is a pressure claw controller, 17 is a pressure signal, and 18 is a positioner 12.
9 is a turbine, 30 is a combustor, 31 is a generator, 33 is a reduction gear, and 34 is a starter.

40 is a snubber, 44 is a manifold, 51 is a filter, 53 is a safety valve, 57 is a cooling water line, 58 is a lubricating oil line, 59 is a suction strainer, 62 is a check valve,
63 is a filter, 69 is a lubricating oil tank, 70 is an emergency lubricating oil pump electric motor, 71 is an auxiliary lubricating oil pump electric motor, and 77 is a check valve.

〔Effect of the invention〕

The present invention eliminates the need for electric motors or other prime movers and their associated systems.

Additionally, the system that combines the gas turbine and gas compressor becomes extremely compact.

[Brief explanation of the drawing]

Fig. 1 is a diagram of a shaft-driven gas compressor system according to an embodiment of the present invention, Fig. 2 is a diagram of a conventional gas compressor system, Fig. 3 is a diagram of a conventional gas turbine lubrication system, and Fig. 4 is a diagram of a conventional gas turbine oil system.
Figure 5 is a diagram of a conventional gas turbine cooling water system, Figure 5 is a system diagram that integrates the gas turbine and gas compressor cooling water systems, and Figure 6 is a system diagram that uses discharge air as an air source for combustion gas control. , Fig. 7 is a conventional combustion gas supply system diagram, Fig. 8 is a parent-child valve characteristic diagram, Fig. 9 is an injection air system diagram, and Fig. 10 is a lubricating oil system when using a shaft-driven fuel gas compressor. It is a diagram. 44... Manifold, 45... Bypass control valve, 46... Check valve, 47... Safety valve.

Claims (1)

[Scope of Claims] 1. A gas turbine equipped with a shaft-driven fuel gas compressor, characterized in that the gas turbine shaft power is used as the driving force for fuel gas compressor system equipment. 2. A gas turbine equipped with a shaft-driven fuel gas compressor according to claim 1, characterized in that a lubricating oil system for the gas turbine and the gas compressor is integrated. 3. A gas turbine equipped with a shaft-driven fuel gas compressor according to claim 1, characterized in that a cooling water system for the gas turbine and the gas compressor is integrated. 4. A gas turbine equipped with a shaft-driven fuel gas compressor according to claim 1, wherein a part of the compressed air for the gas turbine is extracted and used as a control air source for the gas compressor.