RU2482302C2 - Gas turbine plant for conversion of associated petroleum gas into power - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: gas turbine plant for conversion of associated petroleum gas into power comprises an air compressor, a turbine, a combustion chamber, a power generator and a device o air heating downstream the compressor, comprising a heat exchange regenerator device arranged in an exhaust pipe. The combustion chamber with the exhaust pipe are arranged in the form of a surface flare for burning of associated petroleum gas. The compressor is equipped with an electric drive. The turbine at the outlet side is communicated with environment with the help of an autonomous pipe. The surface flare at the side of associated petroleum gas supply is made with a device of atmospheric air intake.

EFFECT: expanded area of gas turbine plant application, increased efficiency of carbon fuel usage and improved environmental capability of environment.

2 cl, 2 dwg

Description

The invention relates to the field of energy and can be used in the oil industry in fields where there are constant emissions of associated petroleum gas (APG).

The closest in technical essence to the invention are gas turbine units (GTU) of 6 MW type GT-750-6 and 10 MW GTK-10-4 (A.I. Rybnikov et al. monitoring the technical condition and operation safety of turbine units ГТК-10-4 and ГТ-750-6 ”, J. Territory Neftegaz, No. 2, 2009), performed with a regenerative cycle (see GOST R 51852-20001. Gas turbine units. Terms and definitions (ISO 3977-1) containing an air compressor, a turbine, a combustion chamber, devices heating the air after the compressor, which includes a heat exchanger-regenerator mounted in the exhaust pipe, a supercharger for a gas pumping unit (GPU) or an electric generator for generating electricity (prototype). The essence of the regenerative cycle is that the air entering the combustion chamber after the compressor is preheated in a heat exchanger-regenerator installed in the exhaust pipe, due to the heat of the exhaust gases after the turbine, and providing the necessary temperature in front of the turbine etsya by combustion of natural gas in the combustion chamber.

The disadvantage of a purely regenerative gas turbine unit is that it is not possible to use APG in it without special preparation (without gas purification and pressure increase).

The technical task of this invention is to expand the scope of the GTU with a regenerative cycle in the interests of the fuel and energy complex, as well as to increase the efficiency of the use of hydrocarbon fuels and to improve the environment by reducing harmful emissions of nitrogen oxides NOx and carbon oxides CO during the combustion of associated gas.

The problem is achieved in that in the proposed gas turbine unit containing an air compressor, a turbine, a combustion chamber, an electric generator and a device for heating the air after the compressor, including a heat exchanger-regenerator located in the exhaust pipe, according to the invention, the combustion chamber with the exhaust pipe is made in the form surface flare unit for flaring associated petroleum gas. The compressor is equipped with an electric drive, the turbine on the outlet side is connected to the environment using an autonomous pipe, and the ground flare installation on the side of the supply of associated petroleum gas is made with a device for intake of atmospheric air.

The combined layout of the exhaust pipe and the combustion chamber and their implementation in the form of a surface flare unit for flaring associated petroleum gas with a design that provides the relevant requirements set forth in the normative and technical documentation allows

- ensure safety, increase the efficiency of the process and the environment;

- to carry out the heating of the working fluid of the turbine in the heat exchanger to the required temperature, which ensures high uniformity of the temperature field of the working fluid (clean air) in front of the nozzle of the turbine;

- organize the combustion process of associated petroleum gas with low pressure (less than 0.1 MPa) and without special preparation, which simplifies the technology, reduces the complexity and provides less harmful emissions.

The connection of the cavity after the turbine with the environment through the cavity of the ground-based flare unit, in particular, increases the power characteristics of gas turbines, since ground-based flare units are injected along the flow path, which provides a higher degree of expansion of the working fluid on the turbine, and therefore, a greater her power.

The implementation of the compressor with another drive, namely with an electric drive, and the connection of the cavity after the turbine with the environment as a separate pipe is relevant for generating electricity of several tens of kW and at low compression ratios of the compressor (about 2). This technical solution greatly simplifies the design of the installation, but there will be a limitation on the maximum power value, since the turbine of the electric generator must generate in the electric generator still the power necessary to drive the compressor with an electric motor.

The proposed gas turbine installation is shown schematically in the drawings of figures 1 and 2.

Figure 1 presents the gas turbine installation according to the proposed technical solution.

Figure 2 schematically shows a fragment of the installation for a variant of the compressor with electric drive.

The gas turbine installation contains an air compressor 1, a turbine 2, an electric generator 3 and a device 4 for heating the air after the compressor (see figure 1). In turn, the device 4 includes a heat exchanger-regenerator 5, which is installed in the exhaust pipe 6, and a combustion chamber 7, made in conjunction with the pipe 6 in the form of a ground flare associated gas burning unit. The compressor is connected to the turbine 2 (see figure 1) or to an electric motor 8 (see figure 2). The generator in both cases is connected to the turbine 2. The outlet cavity after the compressor 1 is connected to the heat exchanger-regenerator 5 using the pipeline 9, and the outlet from the heat exchanger is connected to the cavity of the turbine 2 using the pipeline 10. The cavity after the turbine 2 communicates with the ground flare cavity installation using the pipe 11 or with the environment through an autonomous pipe 12 (see figure 2). In the latter case, the ground flare unit is made with a device 13 for intake of atmospheric air.

Gas turbine installation operates as follows.

Using pneumatic or electric starters (not shown in figure 1), and for the variant shown in figure 2, using the electric motor 8, the compressor is unwound. The air after the compressor enters the heat exchanger-regenerator 5 and the turbine 2, which drives the generator. At a certain pressure value, after the compressor, associated petroleum gas is supplied to the ground flare unit, where its combustion is organized. The resulting heat heats the air in the heat exchanger, which, with the required temperature, enters the turbine to increase its power. When the turbine power exceeds the power consumption of the compressor, the preliminary rotation of the rotor stops and the gas turbine enters a mode that provides the necessary frequency and voltage of the generator. The generated electricity is spent on the own needs of the field and is sent to various consumers.

Estimated calculations using the actual volumes of constant APG emissions at various fields and the initial data of gas turbines of the GT-750-6 type (with a capacity of 6 MW) and GTK-10-4 (with a capacity of 10 MW) show that using these gas turbines and the proposed technical solution, to process a small part of the total APG discharged into fields into electricity, but at the same time save natural gas consumption from 20 to 30 million nm ³ / year, which is very important from the point of view of economic efficiency. On the other hand, nothing prevents the implementation of this project to use more powerful gas turbines or to modernize them in larger quantities at one field.

The proposed device for processing associated petroleum gas into electricity allows us to simplify the technology of its use, as organized combustion of APG at low pressure (after the last stage of separation) and without special treatment. Moreover, the combustion of APG in a surface flare unit with active air supply improves the combustion process and, consequently, reduces harmful emissions of NOx and CO.

Claims (2)

1. A gas turbine installation for processing associated petroleum gas into electricity, comprising an air compressor, a turbine, a combustion chamber, an electric generator and a device for heating the air after the compressor, including a heat exchanger-regenerator located in the exhaust pipe, characterized in that the combustion chamber has an exhaust the pipe is made in the form of a ground flare unit for the flaring of associated petroleum gas. 2. The gas turbine installation according to claim 1, characterized in that the compressor is equipped with an electric drive, the turbine on the outlet side is in communication with the environment using an autonomous pipe, and the ground flare installation on the side of the supply of associated petroleum gas is made with an atmospheric air intake device.

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