RU2622143C1 - Method of use of organic rankine cycle plant for providing objects of crude oil treating plant with heat energy - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: method of using the organic Rankine cycle (ORC-module) for providing objects of a crude oil treating plant with heat energy is that for heating crude oil, commercial oil, water for desalting and dehydration, as well as domestic water in a thermal oil boiler by burning natural or oil-associated gas. The intermediate heat transfer medium is heated, sent to the organic Rankine cycle plant for heating working fluid until it is vaporized. Then, the cooled water, supplied to the organic Rankine cycle plant from the objects of the crude oil treating plant, is heated by the intermediate heat transfer medium and, already heated, directed back via the cycle circuit. And the steam of the hot working fluid is fed to the turbine wheel of the organic Rankine cycle plant, driving the power generator to generate power.

EFFECT: increased reliability of providing objects of a crude oil treating plant with heat energy.

3 cl, 1 dwg

Description

FIELD OF THE INVENTION

The invention relates to the oil industry and can be used in installations for field treatment of oil (UPPN) for heating oil and water using heat obtained by the combustion of natural or associated petroleum gas.

State of the art

A known energy system based on the organic Rankine cycle for the combustion of associated petroleum gas (RF patent No. 2573541, IPC F02C 3/00, published date 01/20/2016), which includes an oil boiler, a circuit with an intermediate coolant, connecting the boiler and the installation based on Organic Rankine Cycle (ORC), which is a closed loop with an organic working fluid containing a turbine on a shaft with an electric generator, an evaporator, a condenser, a heat exchanger-recuperator and a pump, and a plant cooling system. The system is equipped with a burner for the complete combustion of associated petroleum gas installed in the oil boiler, a bypass line connecting the pipeline to exhaust the exhaust gases into the combustion chamber of the oil boiler, and also an air supply line connected to the burner for the complete combustion of natural or associated petroleum gas and passing through the heat exchanger of the cooling system of the installation based on the organic Rankine cycle.

The disadvantage of this method of using an energy system based on the Rankine cycle is that the system is used in a narrow range of applications, only for generating electricity.

A tubular heating furnace is known (RF patent No. 2409610, class IPC C10G 9/20, published date 01/20/2011), including a radiant chamber lined with heat-resistant material, a radiant product coil consisting of pipes interconnected by doubles and suspended on brackets, fixed to the wall of the radiant chamber, underneath with burner devices, a vault, a convection chamber lined with heat-resistant material, a convective food coil, consisting of finned tubes installed in the holes of the support grids and interconnected doubles, an adapter and a chimney, each of the pipes of the radiant and convective grocery coils is put into the shell pipe, and the gap between the pipes and shell pipes is filled with microporous heat transfer powder.

The disadvantage in the operation of this equipment is the narrow range of application of the furnace.

The closest to the proposed technical solution for the achieved technical result is the heating scheme of the UPPN facilities in which the heat source is PTB furnaces (RD 3688-00220302-003-04 Guidance document. Tubular heating furnaces. Design, manufacturing and operation requirements. Replaced by GOST R 53682-2009 “Heating installations for oil refineries. General technical requirements” dated 12/07/2011; “Operating Instructions for Tube Furnaces PTB-10/64”, LLC “LUKOIL-PERM”, Perm, 2004,) , intended for fire heating of oil and water production wells. The principle of operation of the PTB furnace is that the heated product during its movement through the coil sections is heated due to the heat given off by the combustion products of natural gas, associated gas or a mixture thereof, burned in the combustion chambers and entering the space of the heat exchange chamber, which is a metal spatial structure, consisting of a frame, external and internal cladding, the space between which is filled with insulating material. In the lower part of the chamber body there are holes for installing and fixing combustion chambers. Coils consisting of steel pipes are located inside the heat exchange chamber. The heated product (crude oil, marketable oil, water for the installation of desalination and dehydration (OOU)) after heating in the coils of the heat exchange chamber is sent for further preparation to UPPN.

The disadvantage of PTB furnaces is a low efficiency (not more than 67%), low heat transfer of heating surfaces due to clogging of the surface of the finned tubes of the coils of the combustion products, which leads to additional fuel consumption and a decrease in the reliability of operation of the furnace, as well as a narrow range of functional use of the furnace.

The technical result of the proposed method is to increase the utilization of the installation (up to 90%) by expanding the range of use, including providing both thermal and electric energy to the facilities of the field oil treatment plant.

The technical result of the proposed method is also to increase the degree of reliability of providing thermal energy to the objects of the oil field treatment installation.

The technical result, which consists in expanding the range of use, is achieved due to the fact that the intermediate heat carrier heated in a thermal oil boiler due to gas combustion is sent to a unit based on the organic Rankine cycle, they heat the working fluid with it to a vapor state, and then cold water is heated with steam of the working fluid received at the plant on the basis of the organic Rankine cycle from heat exchangers for heating crude oil, commercial oil, water heating for OOU UPPN, and then hot water y is sent back to the heat exchangers crude heating tank oil, water heating UPPN TOC, the vaporized working fluid is also fed to the turbine power generator to generate electricity.

The technical result, which consists in increasing the degree of reliability of the method used, is achieved by the fact that heating of crude oil, marketable oil, water for a desalination and dehydration unit (OOU) of UPPN is also carried out by transferring heat energy from hot water heated in a heat exchanger "hot intermediate heat carrier / water "through a cyclic water circuit, including hydraulically interconnected heat exchanger" hot intermediate heat carrier / water ", heat exchangers for heating crude oil, not commercial water heating for OOU UPPN, while the intermediate heat carrier is heated in a thermal oil boiler.

Brief Description of the Drawings

In FIG. 1 shows a system for providing thermal energy to objects of an oil field treatment unit (UPPN) using a unit based on the organic Rankine cycle that implements the proposed method.

The implementation of the invention

A method of providing thermal energy to facilities of an oil field treatment unit (UPPN) using a unit based on the Rankine organic cycle is implemented through a system including:

a) the cyclic circuit of the working fluid (organic oil) inside the unit based on the organic Rankine cycle,

b) the cyclic circuit of the intermediate coolant (diathermic oil - hereinafter referred to as DTM),

c) the main cyclic circuit through which heat is transferred from the working coolant (organic oil) from a plant based on the organic Rankine cycle to UPPN facilities,

d) an additional cyclic circuit through which heat is transferred from the intermediate coolant (DTM) using sections of the pipelines of the main cyclic water circuit to the UPPN facilities.

Elements of the system of these circuits that provide thermal energy to the facilities of the oil field treatment unit (UPPN) using the unit based on the organic Rankine cycle and implementing the proposed method are:

- node 1 mixing and reduction of natural and associated petroleum gas,

- thermal oil boiler 2,

- pipeline 3 for supplying a mixture of associated petroleum gas (APG) and natural gas from node 1 to the burner of the thermal oil boiler 2,

- collector 4 with a group of pumps for direct supply of heated DTM to a plant based on the organic Rankine 6 cycle,

- a pipeline 5 for supplying an intermediate coolant (diathermic oil) from a collector 4 to a plant based on the organic Rankine 6 cycle,

- a plant based on the organic Rankine cycle (ORC module) 6,

- heat exchanger 7 (diathermic oil-water) additional cyclic circuit,

- pipe 8 for supplying an intermediate coolant (DTM) from the collector 4 to the heat exchangers 7 of an additional cyclic circuit,

- a collector 9 with a group of pumps for the reverse supply of cooled DTM to the thermal oil boiler 2,

- a pipeline 10 for supplying a cooled DTM from a heat exchanger 7 through a collector 9 to the input of a thermal oil boiler 2,

- a pipe 11 of the outlet of the cooled DTM from the plant based on the organic Rankine 6 cycle through a collector 9 to the input of the thermal oil boiler 2,

- expansion membrane tank 12 for regulating the supply and pumping of the intermediate coolant (DTM), hydraulically connected to the installation based on the organic Rankine 6 cycle.

A plant based on the organic Rankine 6 cycle includes:

- the evaporator 13, in which the transfer of heat from the intermediate fluid (DTM) to the working fluid (organic oil),

- pipe 14 for supplying steam generated from the working fluid to the turbine wheel 15,

- a condenser 16, which receives: a) excess steam of the working fluid through the pipe 17 from the evaporator 13, b) cooled steam of the working fluid through the pipe 18 from the turbine 15, c) the cooled water of the main cyclic circuit from the UPPN objects through the pipe 30,

- pipe 19 return of the cooled working fluid from the condenser 16 back to the evaporator 13,

- air coolers (air coolers) 20 with a pipeline 21 for supplying hot water from a unit based on the organic Rankine 6 cycle, which requires cooling, and a pipe 22 for draining the water cooled to the required temperature back to the unit based on the organic Rankin 6 cycle.

The elements of the facilities for the field oil treatment unit (UPPN) that consume the thermal energy of the unit based on the organic Rankine 6 cycle through a water coolant are heat exchangers 23 of the crude oil heating unit from the field; heat exchangers 24 block oil heating; heat exchangers 25 block fresh water heating for OOU; household premises (office building, fire department, dining room, etc. - not shown in the diagram).

The main cyclic circuit through which heat energy is transferred from the working coolant (organic oil) of an installation based on the organic Rankine 6 cycle to UPPN facilities includes:

- the main pipeline 26 for supplying hot water from a plant based on the organic Rankine 6 cycle,

- pipeline 27 for supplying hot water from the main pipeline 26 to the heat exchangers 23 of the heating block of crude oil from the field,

- pipeline 28 for supplying hot water from the main pipeline 26 to the heat exchangers 24 of the heating unit of commercial oil,

- pipeline 29 for supplying hot water from the main pipeline 26 to the heat exchangers 25 of the fresh water heating unit for the OOU,

- the main pipe 30 of the discharge of chilled water entering the input of the capacitor 16 of the installation based on the organic Rankine 6 cycle,

- a chilled water discharge pipe 31 from heat exchanger 23 for the heating of crude oil UPPN hydraulically connected to the main discharge pipe 30,

- the pipeline 32 of the discharge of chilled water from the heat exchangers 24 of the heating unit of commercial water UPPN, hydraulically connected to the main pipeline of the outlet 30,

- a pipe 33 for discharging chilled water from heat exchangers 25 of a fresh water heating unit for the OOU.

An additional cyclic loop for the transfer of thermal energy to UPPN objects from an intermediate heat transfer medium (DTM) from a thermal oil boiler 2 includes:

- the pipeline 34 of the discharge of chilled water from the heat exchangers 23, 24, 25 of the facilities UPPN, through pipelines 31, 32, 33 and a portion of the pipeline 30, to the heat exchanger 7

- a pipeline 35 for supplying hot water from a heat exchanger 7, through pipelines 27, 28, 29 and a portion of a pipeline 26 to heat exchangers 23, 24, 25 of the UPPN facilities from a unit based on the organic Rankine 6 cycle.

The work on providing the field oil treatment unit (UPPN) with thermal energy using a unit based on the organic Rankine cycle is carried out as follows: associated petroleum gas or its mixture with natural gas, or natural gas is sent to the burner of the thermal oil boiler 2 through the mixing and reduction unit 1 through pipeline 3. As the main fuel in the thermal oil boiler 2, associated petroleum gas (hereinafter - APG) is used, and natural gas or a mixture of APG and natural gas is used as reserve fuel. If the pressure or calorific value of the main fuel is lower than the required level, the mixing and reduction unit 1 automatically mixes the reserve fuel to the main fuel in the amount necessary for combustion, or completely replace the feed to the supply of reserve fuel.

The mixing and reduction unit 1 is designed to regulate the supply of fuel to the thermal oil boiler 2 with the aim of heating an intermediate heat carrier, which is used diathermic oil (hereinafter - DTM), for example, "Terminol-66", whose thermal stability is 345 ° C. When using a heat-conducting liquid under the specified specific conditions of a specific industrial application, with a thermal stability index lower than that indicated, low-boiling decomposition products and high-boiling decomposition products are formed and accumulate, which leads to coking and clogging of the heat-conducting system, reducing its durability.

The heated DTM from the thermal oil boiler 2 is pumped by a group of pumps into the collector 4 of a direct supply of DTM. From the collector 4, the heated DTM is sent through pipeline 5 to a plant based on the Rankine organic cycle 6 and / or via pipeline 8 to a heat exchanger 7 (diathermic oil / water). The thermal energy consumption of the diathermic oil is regulated by a unit based on the organic Rankine 6 cycle or by a heat exchanger 7 by estimating the return temperature of the DTM, which is returned to the thermal oil boiler 2 via pipeline 10 and 11 through the oil return manifold 9 from all heat consumers. At high return temperatures, DTMs reduce the gas supply to the burner of the thermal oil boiler 2.

Diathermic oil transfer pumps are performed on separate platforms and installed at an optimum close distance from the thermal oil boiler 2 in order to obtain the minimum length of the DTM feed pipe section 5 to the installation based on the organic Rankine 6 cycle under high oil pressure.

An expansion membrane tank 12 for collecting oil used to maintain the working pressure in the circuit, for example, to pump the DTM from the heating system for the period of its maintenance or in case of leakage of the DTM from the pipelines, is hydraulically connected to the supply pipe 5 of the DTM to the plant based on the organic Rankine 6 cycle and pipeline 11 reverse transport DTM from the installation based on the organic Rankine cycle 6.

DTM movement cycles are ensured by the presence of direct feed 4 and 9 reverse feed collectors.

The operation of the DTM circuit in a plant based on the Rankine 6 organic cycle is as follows. From a thermal oil boiler 2 DTM with a temperature of 280-302 ° C, a flow rate of 65-70 kg / s, a pressure of 0.5 MPa, it is directed to a collector 4 of a direct supply of DTM and then through pipeline 5 to the evaporator 13 of the plant based on the organic Rankine 6 cycle, where due to heat transfer, DTM gives up part of the heat of the working fluid. After heat transfer, a cooled DTM with a temperature of 242 ° C is sent through a pipe 11 through a return manifold 9, a pipe 10 and a system of valves and circulation pumps back to the thermal oil boiler 2, where the DTM is again heated by burning the incoming mixture of associated petroleum gas and natural gas, which allows efficient utilization of associated petroleum gas, reducing atmospheric emissions.

The operation of the DTM circuit on the heat exchanger 7 is as follows. At the same time (or periodically) with the operation of the DTM circuit on a plant based on the organic Rankine 6 cycle, DTM from a thermal oil boiler 2 with a temperature of 280-290 ° C, a flow rate of 65-70 kg / s, a pressure of 0.5 MPa, is directed through a direct feed collector 4 and a pipe 8 to the inlet of the heat exchanger 7, in which heat energy is transferred to the chilled water entering the heat exchanger 7 through a pipe 34 from pipelines 31,32,33 through a section of the main branch pipe 30. The DTM circuit works on the heat exchanger 7 in case of a stop of the circuit DTM on a plant based on the organic Rankine 6 cycle or in parallel with it.

The work of the working fluid circuit, which is used as an organic oil, on a plant based on the organic Rankin 6 cycle is carried out as follows: a working fluid with a temperature of 260-262 ° C and a pressure of 0.97 MPa, located in the condenser 16 of the plant based on the organic Rankin cycle 6, through a pipe 19 is sent through an intermediate heater to the evaporator 13, heating it to a boiling point. In the evaporator 13, the working fluid, additionally heated by heat transfer from DTM to 265 ° C (P = 0.93 MPa), evaporates with the formation of steam, which is then supplied through pipe 14 to the turbine wheel 15, which drives the electric generator. The torque on the shaft of the turbine generator 15 is controlled by supplying saturated steam of the working fluid. The steam generated after the turbine 15, in the circulation mode, is sent back through the pipe 18 to the condenser 16, in which it is used to heat the working fluid received through the pipe 17 from the evaporator 13, and to heat the chilled water received through the pipe 30 of the main cyclic water circuit from facilities UPPN. After heating the water in the range of 65-95 ° C in the condenser 16, the hot water is sent through the pipeline 26 of the main cyclic water circuit and pipelines 31, 32, 33 to the heat exchangers 23, 24, 25 of the UPPN objects. After heat transfer through the pipeline 27 to the heat exchanger 23 of the crude oil heating unit coming from the field, through the pipeline 28 to the heat exchanger 24 of the commercial oil heating unit and through the pipeline 29 to the heat exchanger 25 of the fresh water heating unit for OOU chilled water through pipelines 31, 32, 33 sent back to the main pipe 30 of the main cyclic circuit and fed to the reception of the capacitor 16 or to the reception of the heat exchanger 7 of the heating circuit DTM. The cycle of heating the carrier of thermal energy to the objects UPPN repeat.

To remove the heat load from a plant based on the organic Rankine cycle, dry air coolers (air coolers) 20 are used, cooling the hot water received through the pipe 21 from the condenser 16. The cooled water through the pipe 22 is directed to the inlet of the condenser 16, increasing the volume of heat transfer by increasing the flow rate incoming chilled fluid.

Both sources of thermal energy (DTM heated in a thermo-oil boiler, and organic oil heated using DTM), as well as the main and additional cyclic circuits, have their own group of pumps and shutoff valves and can function independently of each other.

With an increase in thermal energy consumption at UPPN facilities, the system that implements the proposed method provides an increase in the production of thermal energy from diathermic oil in boiler 2. If necessary, the electric energy generation from the installation on the basis of the Rankine 6 organic cycle decreases, with the complete shutdown of the operation of boiler 2 -installation based on the organic Rankin 6 cycle, leaving only the "boiler 2-heat exchanger 7" circuit in operation.

In the event of an emergency, such as a rupture of the diathermic oil circuit pipeline, or while the unit is operating on the basis of the Rankine 6 organic cycle, a diathermic oil collection tank is used. The collection of oil is carried out by opening the necessary drain lines of the diathermic oil circuit. The expansion membrane tank 12 is designed to maintain operating pressure in the diathermic oil circuit.

The main condition for regulating the operation of the installation is the production of thermal energy in the required volumes, while the electricity generated using the installation based on the organic Rankine 6 cycle is secondary.

There are several conditions for regulating the process of obtaining the required amount of heat:

- change of diathermic oil usage modes,

- regulation of the process of production of electricity produced by the installation based on the organic Rankine 6 cycle,

- discharge of thermal energy through air coolers (air coolers) 20.

With an increase in heat energy consumption from the UPPN heat exchangers for heating crude oil, marketable oil or water, the system automatically ensures an increase in the production of thermal energy from diathermic oil from the side of boiler 2 due to a decrease in the generation of electricity from the installation based on the organic Rankine 6 cycle, or due to turn it off completely. When sufficient heat capacity is reached, a plant based on the Rankine 6 organic cycle is returned to the previous level of power generation consumed by the facilities of UPPN.

The proposed method is implemented on the installation of oil field treatment "Osa" LLC "LUKOIL-Perm."

Claims (3)

1. The method of using the unit based on the organic Rankine cycle to provide thermal energy to the facilities of the oil field treatment plant (UPPN), characterized in that they produce heating of crude oil, marketable oil, water for the installation of desalination and dehydration (OOU) UPPN by burning associated petroleum gas or its mixture with natural gas or by burning natural gas, characterized in that the intermediate heat carrier heated in a thermal oil boiler by burning gas is sent to the installation on the basis of f of the organic Rankine cycle, they heat the working fluid with it until a vapor state, after which the steam of the working fluid heats the cold water that enters the unit based on the organic Rankine cycle from heat exchangers for heating crude oil, commercial oil, water for OOU UPPN, and then hot water sent back to heat exchangers for heating crude oil, commercial oil, water for OOU UPPN, while the vaporous working fluid is also sent to the turbine wheel of the unit based on the organic cycle Renk for actuating the electric generator to generate electricity. 2. The method according to p. 1, characterized in that the heating of crude oil, commercial oil, water for the installation of desalination and dehydration (OOU) UPPN also produce by transferring heat energy from hot water heated in a heat exchanger "hot intermediate heat carrier / water" on a cyclic water circuit comprising hydraulically interconnected heat exchanger “hot intermediate heat carrier / water”, heat exchangers for heating crude oil, commercial oil, water heating for OOU UPPN, while the intermediate heating medium t in thermal oil boiler. 3. The method according to p. 1, characterized in that an organic oil is used as a working fluid, and diathermic oil is used as an intermediate heat carrier.

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