RU139073U1 - INSTALLATION OF LOW TEMPERATURE OIL GAS PROCESSING - Google Patents

Abstract

1. Installation of low-temperature processing of petroleum gas, containing a pipeline for supplying hydrocarbon gas to a multithreaded heat exchanger equipped with an inlet and outlet of hydrocarbon gas, as well as inlets and outlets of gas flows, a propane cooler with an inlet of hydrocarbon gas connected to a multi-flow heat exchanger and an outlet of hydrocarbon gas, a separator , a turboexpander, a throttle, a first fractionating column equipped in the upper part with an outlet of stripped gas and an inlet for supplying irrigation, and in the lower part with an outlet a hydrocarbon condensate house connected to a second fractionating column provided in the upper part with a gas phase outlet and an inlet for irrigation supply, and in the lower part with a liquid product outlet, characterized in that the installation is equipped with an additional propane cooler connected to the hydrocarbon gas supply pipe, the output of hydrocarbon gas from an additional propane cooler is connected to a propane cooler, the output of hydrocarbon gas from which is connected to the inlet of a multi-flow gas stream LfTetanus exchanger, furthermore, the output of the gas phase of the second fractionating column is connected via threaded exchanger inlet for supplying irrigation first fractionator, and the stripped gas outlet of the first fractionator is connected via threaded exchanger with the turbo expander and further with potrebitelem.2. The low-temperature processing of petroleum gas according to claim 1, characterized in that the installation is equipped with an additional recuperative heat exchanger connected via a first coolant to the pipe

Description

The utility model relates to devices for processing hydrocarbon gas by low-temperature condensation and can be used in the oil and gas refining industry.

A known installation for separating a gas stream (see Eurasian patent No. 001330, F25J 3/02, publ. 02.26.2001 in OB No. 1), containing a gas supply pipe, first and second multi-threaded heat exchangers connected, respectively, with the first and second propane refrigerators, a recuperative heat exchanger, a throttle, a separator with gas and hydrocarbon condensate outlets, a turboexpander, a hydrocarbon fractionation unit with a mass transfer column equipped with residual gas and liquid product outlets, and a residual g compression unit aza, while the output of the residual gas from the mass transfer column is connected to a recuperative heat exchanger, the first and second multi-threaded heat exchangers, and then to the residual gas compression unit, in addition, the first multi-flow heat exchanger is connected to the lower part of the mass transfer column.

Common features of the known and proposed installations are:

- hydrocarbon gas supply pipeline;

- a multi-threaded heat exchanger equipped with an inlet and outlet of hydrocarbon gas, inlets and outlets of gas flows;

- propane refrigerator;

- separator;

- turbo expander;

- throttle;

- fractionating column, equipped in the upper part with the outlet of stripped gas and the inlet for irrigation, and in the lower part with the outlet of the liquid product.

A disadvantage of the known installation is the high capital and operating costs due to the presence on the installation of only one refrigerant isotherm.

The closest in technical essence and the claimed result is the installation of low-temperature gas processing described in patent No. US 4854955, F25J 3/02, publ. 08/08/1989 (see Fig. 3) and including a hydrocarbon gas supply pipe, first and second multithreaded heat exchangers equipped with inlets and outlets of hydrocarbon gas, gas and condensate flows, a propane cooler with a hydrocarbon gas inlet connected to the first multithreaded heat exchanger, and an outlet hydrocarbon gas connected to the second multi-threaded heat exchanger, separator, turbo-expanders, throttle, air coolers, stripped gas heat exchanger, as well as the first fractionation column with the output bleached gas and an inlet for supplying irrigation in the upper part and an outlet of liquid product in the lower part connected to the inlet for supplying irrigation of a second fractionating column equipped with outlets of gas and liquid phases. In this case, the outlet of the gas phase of the second fractionating column is connected to the heat exchanger of the stripped gas and then to the inlet for supplying irrigation of the first fractionating column, the outlet of the stripped gas of the first fractionating column is connected in series with the heat exchanger of the stripped gas, the second and first multithreaded heat exchangers, a turboexpander, the first air cooler, compressor, second air cooler and further with the consumer.

Common features of the known and proposed installations are:

- hydrocarbon gas supply pipeline;

- a multi-threaded heat exchanger equipped with an inlet and outlet of hydrocarbon gas, an inlet and outlet of gas flows;

- a propane refrigerator with a hydrocarbon gas inlet connected to a multi-threaded heat exchanger and a hydrocarbon gas outlet;

- separator;

- turbo expander;

- throttle;

- the first fractionation column, equipped in the upper part with a stripped gas outlet and an inlet for irrigation supply, and in the lower part with a hydrocarbon condensate outlet connected to the second fractionation column;

- the second fractionation column is equipped in the upper part with the outlet of the gas phase and the inlet for supplying irrigation, and in the lower part with the outlet of the liquid product.

A disadvantage of the known installation is the high capital and operating costs due to the presence on the installation of only one refrigerant isotherm.

The technical result of the proposed utility model is to reduce capital and operating costs through the use of several isotherms of refrigerant boiling.

The specified technical result is achieved by the fact that in the installation of low-temperature processing of oil gas containing a pipeline for supplying hydrocarbon gas to a multi-threaded heat exchanger equipped with an inlet and outlet of hydrocarbon gas, as well as inlets and outlets of gas flows, a propane refrigerator with an inlet of hydrocarbon gas connected to a multi-flow heat exchanger, and with a hydrocarbon gas outlet, a separator, a turboexpander, a throttle, a first fractionating column equipped in the upper part with a topped g outlet behind and the inlet for irrigation supply, and in the lower part - the output of hydrocarbon condensate connected to the second fractionating column, equipped in the upper part with the gas phase outlet and the inlet for irrigation supply, and in the lower part - with the liquid product outlet, according to the utility model, the installation is equipped with an additional a propane refrigerator connected to the hydrocarbon gas supply pipe, wherein the hydrocarbon gas output from the additional propane refrigerator is connected to a propane refrigerator, the hydrocarbon output about gas from which is connected to the gas flow inlet of the multi-flow heat exchanger, in addition, the gas phase output of the second fractionating column is connected through a multi-flow heat exchanger to the inlet for supplying irrigation to the first fractionation column, and the outlet of stripped gas from the first fractionating column is connected through a multi-flow heat exchanger with a turbine expander and then to by consumer.

In addition, the installation is equipped with an additional recuperative heat exchanger connected via a first heat carrier with a hydrocarbon gas supply pipeline and a separator, and through a second heat carrier with a hydrocarbon condensate outlet of the first fractionating column and an input for supplying raw materials of the second fractionating column.

In addition, the installation can be equipped with an additional air cooler connected to the hydrocarbon gas supply pipe and a propane refrigerator.

The claimed combination of features of the installation allows to reduce operating and capital costs for a propane refrigeration unit (PCU) due to the use of two refrigerant isotherms in the proposed installation - the use of refrigerant boiling at different temperatures and pressures in propane refrigerators. Due to the fact that when using two refrigerant isotherms, the pressure of one of the boiling refrigerant streams is higher than the pressure of the boiling refrigerant when using one refrigerant isotherm, a part of the evaporated refrigerant is compressed to a higher pressure than when using one refrigerant isotherm. This allows you to reduce the energy costs of the installation associated with the compression of the refrigerant. In addition, this allows to reduce the volumetric productivity of propane compressors and thereby reduce the capital costs of PCBs, as when using several isotherms of refrigerant boiling, part of the refrigerant boils at a higher pressure, and as a result, the density of refrigerant vapors at the reception of PCU compressors will be higher, which leads to a decrease in their volumetric capacity. The decrease in compressor volumetric capacity and the degree of compression of the refrigerant vapor lead to a decrease in the cost of the compressor unit.

Providing the installation with an additional recuperative heat exchanger makes it possible to use part of the flow of dried hydrocarbon gas to heat the bottom product of the first fractionation column (hydrocarbon condensate), thereby reducing the operational (energy) costs of the installation.

Providing the unit with an additional air cooler installed in front of the propane cooler allows the use of ambient air cold in winter at a high temperature of the hydrocarbon gas supplied to the unit to reduce the load on the refrigerant evaporators and, therefore, on the PCB, thereby reducing the operating costs of the unit.

The figure shows the proposed installation of low-temperature processing of oil gas.

The installation includes a hydrocarbon gas supply pipe 1, a multi-threaded heat exchanger 2, a propane refrigerator 3, an additional propane refrigerator 4, a separator 5, a turboexpander 6 and a throttle 7.

Multi-threaded heat exchanger 2 has:

- input 8 of hydrocarbon gas;

- input 9 of chilled hydrocarbon gas;

- input 10 of stripped gas;

- input 11 of the gas phase;

- output 12 of hydrocarbon gas;

- output 13 of chilled hydrocarbon gas;

- output 14 of stripped gas;

- output 15 of the gas phase.

The hydrocarbon gas supply pipe 1 is connected to the inlet 8 of the hydrocarbon gas of the multi-threaded heat exchanger 2, as well as to the inlet of the propane cooler 3 and the inlet of the additional propane cooler 4.

The hydrocarbon gas outlet 12 from the multi-threaded heat exchanger 2 and the hydrocarbon gas outlet from the additional propane cooler 4 are connected to the inlet of the propane cooler 3.

The outlet of the propane refrigerator 3 is connected to the inlet 9 of the cooled hydrocarbon gas in a multi-threaded heat exchanger 2.

The outlet 13 of the cooled hydrocarbon gas from the multi-threaded heat exchanger 2 is connected to a separator 5 provided with a gas outlet 16 and a liquid outlet 17.

The gas outlet 16 is connected to a turboexpander 6 and then to an input 18 for supplying raw materials to the first fractionation column 19.

The fluid outlet 17 is connected to the inductor 7 and then to the inlet 20 for supplying raw materials to the first fractionation column 19.

The first fractionating column 19 is provided with an outlet 21 of stripped gas and an inlet 22 for supplying irrigation in the upper part and an outlet 23 of hydrocarbon condensate in the lower part.

The outlet of the stripped gas 21 is connected to the inlet of the stripped gas 10 in the multi-flow heat exchanger 2. The outlet of 14 stripped gas from the multi-flow heat exchanger 2 is connected to the compressor part of the turboexpander 6 and then through the air cooler 24 to the consumer.

The hydrocarbon condensate outlet 23 is connected to the second fractionation column 25 through an inlet 26 for supplying irrigation.

The second fractionation column 25 is provided with an inlet 27 for supplying raw materials, an outlet 28 of the gas phase and an outlet 29 of the liquid product (fraction C _{2 + above} ).

In the lower part of the second fractionating column 25, a riboiler 30 is installed, while the outlet 29 of the liquid product is connected to the riboiler 30.

The installation is equipped with an additional recuperative heat exchanger 31 connected via a first heat carrier with a hydrocarbon gas supply pipe 1 and a separator 5. By a second heat carrier, the input of an additional recuperative heat exchanger 31 is connected to the hydrocarbon condensate outlet 23 of the first fractionation column 19, and the output to an input 26 for supplying raw materials to second fractionation column 25.

The outlet 28 of the gas phase of the second fractionating column 25 is connected to the inlet of the gas phase 11 in the multi-flow heat exchanger 2 and then through the outlet 15 of the gas phase is connected to the inlet 22 for supplying irrigation to the first fractionating column 19.

The installation can be equipped with an additional air cooler 33 connected to the hydrocarbon gas supply pipe 1 and installed in front of the propane refrigerator 3.

To ensure a non-hydrate mode of operation of the equipment (turbo expander 6 and multi-flow heat exchanger 2), the installation is equipped with a unit 34 for preparing and supplying evaporated methanol.

The installation is also equipped with the necessary shut-off and control valves and pumps.

Installation works as follows.

The stream of pre-drained hydrocarbon (oil) gas with a temperature of 35 ° C through line 1 enters the installation and is divided into several streams.

The first stream of (main) hydrocarbon gas through inlet 8 enters a multi-threaded heat exchanger 2, in which it is cooled to a temperature of minus 28 ° C.

The second hydrocarbon gas stream is fed to a propane refrigerator 3 for cooling.

The third stream of hydrocarbon gas enters an additional propane cooler 4, in which it is cooled to a temperature of minus 18 ° C.

The hydrocarbon gas streams cooled in a multi-threaded heat exchanger 2 and an additional propane cooler 4 are directed to a propane cooler 3, in which they are cooled to a temperature of minus 30 ° C. After that, the flow of chilled hydrocarbon gas through the inlet 9 enters a multi-threaded heat exchanger 2, in which it is cooled to a temperature of minus 64 ° C.

If necessary (at a high temperature of the hydrocarbon gas stream entering the installation through pipeline 1) in the cold season, the second hydrocarbon gas stream is preliminarily sent to an additionally installed air cooler 33, in which this hydrocarbon gas stream is cooled to a temperature of about minus 5 due to the cold of the ambient air ° C (depending on air temperature) and then enters the propane cooler 3 together with hydrocarbon gas streams from a multi-threaded heat exchanger 2 and additional tional propane refrigerator 4.

After further cooling in a multi-threaded heat exchanger 2, the combined stream of chilled hydrocarbon gas through the outlet 13 of chilled hydrocarbon gas with a temperature of minus 64 ° C enters the separator 5, which is separated into gas and liquid.

The resulting gas from the separator 5 through the outlet 16 is sent to the turbo expander 6 and then through the input 18 for supplying raw materials enters the first fractionation column 19.

The liquid separated in the separator 5 through the outlet 17 enters the throttle 7 and then through the inlet 20 for supplying raw materials enters the first fractionation column 19.

In the first fractionation column 19, stripping gas and low-temperature hydrocarbon condensate are separated.

The obtained stripped gas with a temperature of minus 117 ° C and a pressure of 1.32 MPa (g) through the outlet 21 of the first fractionating column 19 enters the multi-threaded heat exchanger 2 through inlet 10. From the multi-threaded heat exchanger 2, the stripped gas with a temperature of 22 ° C through the outlet 14 topped gas is fed to the inlet of the compressor part of the turboexpander 6 and then to the air cooler 24, after which it is sent to the consumer with a temperature of 40 ° C.

A hydrocarbon condensate with a temperature of minus 105 ° C and a pressure of 1.37 MPa (g) leaves the first fractionating column 19 and is sent to the second fractionating column 25 in two streams: one stream enters the column 25 through the inlet 26 for irrigation, and the other stream - through the inlet 27 for supplying raw materials. In this case, the hydrocarbon condensate stream entering the second fractionation column 25 as a raw material is preheated to a temperature of 5 ° C in an additional recuperative heat exchanger 31 with a portion of the hydrocarbon gas stream entering the unit through pipeline 1 (fourth hydrocarbon gas stream).

In the second fractionation column 25, the hydrocarbon condensate is separated into a gas phase and a liquid product - ethanized BFLH (fraction C _{2 + above} ).

The gas phase obtained in the second fractionating column 25 with a temperature of minus 88 ° C and a pressure of 2.6 MPa (g) is fed through the gas phase inlet 11 to a multi-flow heat exchanger 2, in which it is cooled and condensed, after which it is minus 115 ° C and a pressure of 1.32 MPa (g.) through the outlet 15 enters the first fractionation column 19 as irrigation.

The liquid product with a temperature of 12 ° C and a pressure of 2.65 MPa (g) through the outlet 29 of the second fractionation column 25 enters the riboiler 30, in which it is heated. After that, the main part of the liquid product stream with a temperature of 26 ° C is sent to the ethane fraction generating unit (not shown in Fig.), And the remaining part of the stream is returned back to the second fractionation column 25 to heat its lower part.

To ensure a non-hydrate operation of the turbo expander 6, where the temperature can drop below minus 100 ° C, as well as a multi-threaded heat exchanger 2, methanol vapors from the unit 34 for preparing and supplying evaporated methanol are fed into the incoming gas flows before entering this equipment.

Claims (3)

1. Installation of low-temperature processing of petroleum gas, containing a pipeline for supplying hydrocarbon gas to a multithreaded heat exchanger equipped with an inlet and outlet of hydrocarbon gas, as well as inlets and outlets of gas flows, a propane cooler with an inlet of hydrocarbon gas connected to a multi-flow heat exchanger and an outlet of hydrocarbon gas, a separator , a turboexpander, a throttle, a first fractionating column equipped in the upper part with an outlet of stripped gas and an inlet for supplying irrigation, and in the lower part with an outlet a hydrocarbon condensate house connected to a second fractionating column provided in the upper part with a gas phase outlet and an inlet for irrigation supply, and in the lower part with a liquid product outlet, characterized in that the installation is equipped with an additional propane cooler connected to the hydrocarbon gas supply pipe, the output of hydrocarbon gas from an additional propane cooler is connected to a propane cooler, the output of hydrocarbon gas from which is connected to the inlet of a multi-flow gas stream LfTetanus exchanger, furthermore, the output of the gas phase of the second fractionating column is connected via a heat exchanger with multi-threaded inlet for supplying irrigation first fractionator, and the yield of lean gas from the first fractionation column is connected through turboexpander multithreaded exchanger and further to the consumer. 2. The low-temperature oil gas processing plant according to claim 1, characterized in that the installation is equipped with an additional recuperative heat exchanger connected via a first heat carrier with a hydrocarbon gas supply pipe and a separator, and by a second heat carrier with a hydrocarbon condensate outlet of the first fractionating column and an inlet for supply raw materials of the second fractionation column. 3. The low-temperature processing of petroleum gas according to claim 1, characterized in that the installation is equipped with an additional air cooler connected to the hydrocarbon gas supply pipe and a propane refrigerator.

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