RU2354431C1 - Installation of field collection, transporting and primary preparation of oil and gas - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention refers to process of field collection, transporting and primary preparation of oil and gas at oil fields, particularly to technology of separation of emulsified hydrocarbon multi-phased mediums and can be implemented in oil and gas refining industry. The installation consists of wells, of a group measuring trap with heating, of a trap-separator of the first stage with filtering-coalescing facility, of a trap-separator of the second stage with a filtering-coalescing facility, of collecting capacities for oil with pontoons, of booster pumps, and of a trap-separator of the third stage with a filtering-coalescing facility. Filtering-coalescing facilities are made in form of a package cutting off working cross section of the capacity and composed out of materials of porous-cellular metals and (or) alloys and (or)porous-cellular polymer materials with a fixed porous-cellular structure.

EFFECT: deep destruction of water-gas-oil emulsion, producing gas flow not containing dropping oil, and oil flow practically not containing formation water, also simplification of installation.

2 dwg, 1 tbl

Description

The invention relates to a technology for field collection and preparation of oil and gas in the oil fields, in particular to a technique for separating emulsified hydrocarbon multiphase media, and in particular to installations for field collection, transportation and preparation of oil and gas, and can be used in oil and gas processing and other industries.

The oil industry is characterized by a large complex of large-capacity industrial stages of powerful production with large-sized metal-intensive equipment, with a large length of communications for transporting raw materials and products, significant areas of industrial sites at intermediate stages of technology from production, collection, transportation, preparation of raw materials (gas, oil) to gas processing and oil refining directly. Field experience has shown that the inevitable companions in the process of oil production are gas and produced water (with impurities) and the general essence of oil and gas preparation is reduced to the deep separation of multicomponent water-gas-oil emulsions into components with further preparation of oil and gas for processing at the respective plants.

Domestic and foreign research and design organizations are working on updating processes and technological schemes that ensure high quality indicators of oil and gas supplied for processing. However, until now, on the whole, the aforementioned production continues to be characterized by high financial costs, metal consumption, large size, and relatively low efficiency of equipment for deep separation of a multicomponent mixture (oil, gas, produced water, mechanical impurities), requiring the use of expensive reagents and electricity. The effects of harmful pollution on the air basin and soil cover from smoking torches and effluents containing oil and reagent pollution continue.

The main oil producing regions today are northern regions with a harsh climate, terrain features and significant remoteness of production areas from field training facilities and in connection with these features of the process.

As a prototype, a standard schematic diagram of the technology of field collection and transportation of oil and gas at the Giprovostokneft Institute is proposed (KS Kasparyants. Field preparation of oil and gas, Nedra Publishing House, M., 1973, p. 118) .

In figure 1 (according to the prototype), the heated oil from the wells (1) through the metering ladder (2) enters the separator ladders of the first separation stage (3). Their purpose is the destruction of water-gas-oil emulsions with the aim of partial separation of gases. The first separation stage is carried out with a decrease in pressure to 7-8 atm, i.e. sufficient for uncompressed supply of the separated gas to the consumer or to gasoline plants (HBZ), if both are closely located and the gas is not difficult to transport. From the experience of field operations, this part of the gas is used at the production site as an energy resource (for heating the oil flow, etc.) and, as a rule, is excessive. The internal design of the separator traps does not provide a deep separation of oil from the gas released in the first stage of separation, and burning excess gas on flare devices leads, in addition to wastefulness, to pollution of the atmosphere and soil around the flares by products of incomplete oil combustion.

At large distances from the drains of the first separation stage (3) and adverse terrain conditions, further transport of oil with the remaining gases dissolved in it is carried out by booster pumps (4) through the collection tank (5) to the second separation stage, which, like the third stage (at if necessary) is already carried out at the centralized collection points for oil and gas in the separator ladders of the second (6) and third stage (7), the volume and quantity of which is not much different from the first stage. At the second stage of separation under the conditions of technology, the separated part of the gas from the drains (6) enters the gas line, and oil containing residual dissolved gas is transported to the next separation stage to the separator drains (7). At the third stage of separation from oil, the residual part of the gas is released, which is combined with the gas stream of the second stage in the common collector and enters the gas-gas plant (GBZ). Oil after the separation ladders of the third stage (7) is a water-oil emulsion and enters the technological prefabricated filling tanks with pontoons (8).

The separator ladders are horizontal tanks, inside which are installed devices for the destruction of gas-oil emulsions. Due to their lack of effectiveness in the destruction of the emulsion, these containers have large dimensions and their number at each stage of separation, depending on the characteristics of the incoming stream, can reach up to 10 or more.

To meet the quality of oil with the standard of the oil refining company for oil-water emulsion, an additional stage of preparation is required depending on the characteristics of the oil in one of the following ways: cold sediment; thermochemical sludge using thermal energy and expensive reagents (demulsifiers); electrical dewatering and desalination using bulky, expensive equipment and electricity, requiring special care in maintaining the technological regime to achieve the required performance. Any of these stages is to a large extent financially and labor-intensive, requiring equipping with large-sized slop and other equipment located on a large area of the industrial site.

Upon reaching the required quality indicators, oil is transported already to oil refineries.

The elimination of these disadvantages is achieved by the fact that in the proposed installation of field gathering, transport and primary treatment of oil and gas, including wells, a group metering ladder, separator ladders in the form of horizontal tanks, inside which there are installed devices for the destruction of gas-oil emulsions made in the form of filtering a coalescing packet overlapping the working section of the apparatus and made up of a composition of materials of porous-cellular metals and (or) alloys, and (or) porous-cellular polymers porous material with a fixed-cell structure, booster pumps, prefabricated container.

The proposed installation allows you to convert a very cumbersome technological scheme of oil and gas field collection and transportation (according to the prototype) into a compact high-performance oil and gas field collection, transportation and primary treatment scheme, eliminating low-efficiency large-sized separator ladders with replacing them with universal ones equipped with high-performance filtering coalescing devices (PKU), allowing to deeply destroy water-gas-oil emulsion with obtaining a gas stream that does not contain drops oil, and the oil stream, practically free of produced water.

The number of units of ladder separators has been reduced to such an amount that now the entire installation can be placed on the industrial site of the pump station (booster pump station).

This innovative reconstruction allows the possibility of using porous-cellular metal and polymeric materials with a fixed porous-cellular structure with optimal surface properties for the working medium in PKU.

The trap separator with PKU is a tank, the size of which as well as PKU can be designed for any performance. High separation efficiency of gas, oil and water is achieved due to the highly developed working surface of the medium contact with a fixed porous-cellular structure of the materials used, having 92-95% of the free volume. The high performance of the separator trap is due to the very low resistance of the filter-coalescing packet within 50 mm of water. The filtering outer surface of porous-cellular materials is able to delay the inclusion of the aqueous phase, in which the solids are usually accumulated, and the depth layers of the filter composition materials remain free from solids, do not require regeneration. If regeneration is necessary, the filter bag is easily washed with the reverse flow of the medium selected for washing.

Figure 2 in General terms presents a schematic flow diagram of the proposed installation of harvesting, transport and primary treatment of oil and gas.

The installation contains wells (1), a group metering ladder with heating (2), a first stage ladder separator with a PKU (3), a second stage ladder separator with a PKU (4), prefabricated oil tanks with pontoons (5), booster pumps (6), third stage trap separator with FCU (7).

Installation works as follows. From the wells (1), heated oil, which is a water-oil emulsion saturated with hydrocarbon gases, through a group metering ladder (2) enters the first stage ladder separator (3), which is a tank equipped with a filter-coalescing device (PKU). The dimensions of the apparatus and PKU are calculated based on the performance of the gas-oil flow. Partial gas separation and partial destruction of the oil-water emulsion take place in the first-stage ladder-separator with a decrease in the initial pressure on the highly developed working surface of porous-cellular filtering-coalescing materials in PKU. The released gas, which may contain drip oil, then flows into the upper part of the second stage drain separator (4), and the oil-water stream enters the lower part of the drain separator (4), where the residual gas is separated when the pressure is reduced to technological standards. Moving through the porous-cellular structure of coalescing materials (PKU), the gas stream is completely freed from drip oil and enters the product gas line, in terms of quality ready for processing at plants and for use by other consumers (as an energy carrier, gas lift, etc. .). The oil-water flow of the emulsion, passing through the layers of porous-cellular materials PKU (4), is subjected to deeper destruction and is discharged into the oil collection tank with pontoons (5). In the collection tank (5), larger globules and formation water lenses settle to the bottom and, when accumulated in the lower part of the tank (5), are automatically discharged, and the oil-water emulsion is pumped by a booster pump (6) into the third stage drain separator (7). Having passed through the porous-cellular layer of PCF of the ladder-separator (7), the oil-water emulsion undergoes deep destruction and complete separation of the oil and water phases.

The low residual content of produced water in the oil leads to a significant reduction in the salt content, and if necessary, further preparation of the oil to the standards for the content at the central collection point (CSP), the costly mechanism can already be significantly reduced both in terms of reagents and equipment volumes. In total, as practice has shown, the proposed scheme allows moisture to be removed from oil in a wide range - from 10 to 85% by volume; in the optimal technological mode of dehydration - to trace concentrations.

The technical result consists in the fact that the proposed installation improves the efficiency of deep separation of gas-oil emulsion into flows:

- gas, not containing drip oil, according to the quality indicators ready for processing at the plants; gas in case of production necessity of burning its excess on a flare does not smoke and does not pollute the soil cover and air basin with products of incomplete combustion of oil;

- oil, deeply dehydrated and partially desalted;

- formation water that does not contain oil inclusions, ready, if necessary, for pumping it into the oil reservoir, and when stored in storage bins, it eliminates soil contamination with oil impurities.

The replacement of inefficient large-sized drain separators with highly efficient ones equipped with filtering-coalescing devices has drastically reduced the volume and quantity of metal-intensive technological equipment, including settling and other equipment. The installation looks very compact and can be placed on the industrial site of the pump station (booster pumping stations).

There is no need to maintain and operate large reagent farms and a significant fleet of bulky and energy-consuming electrical equipment for oil treatment (its deep dehydration and desalination). Accordingly, the cost of the proposed scheme will sharply decrease.

In the event of a decrease in the debit of the well, moving the equipment of the proposed scheme to other promising production sites will be economically acceptable and more profitable compared with the reconstruction according to the prototype scheme.

To confirm the technical and economic advantages of the proposed scheme, the results of pilot tests in real production at the technological units of CSN-1 of the Severo-Gubkinsky field in the Purovsky district of the Tyumen region in the technology of separating droplet oil from associated gas and oil dehydration technology are presented.

The results presented in the Industrial Test Act at the CSN-1 installation of the Severo-Gubkinsky field for collecting droplet liquid from associated gas showed that during a three-month run-in of the trap separator equipped with PKU, a stable mode was found for choosing the optimal mode of separation of oil from gas every 10 hours every 10 hours, 10 m ^{3 of} oil is extracted from gas (thus, the saving of oil burned will be at least 40 m ³ / day - 32 tons / day). At a cost of approximately 7,000 rubles / ton, flaring was prevented: 7,000 rubles × 32 × 365 = 8,176,000 rubles / year.

The results presented in the Act of industrial testing at the installation of CSN-1 of the Severo-Gubkinsky oil dehydration field showed that in the optimal mode of filtering oil-water emulsion through a filter-coalescing device within the filtration rate from 0.0014 to 0.0043 m / s ( table 1) achieved deep oil dehydration.

A high result of deep oil dehydration was achieved without the use of expensive reagent oil preparation using the technology of the prototype.

Table 1
Mode No. 1
The filter is included in parallel to the main line with an estimated productivity of 30% of the flow. Discharge of water 2-3 times a day in manual mode. Samples are point. No. date of The volume of fluid passing through the filter (m ³ / day) Filter flow rate (m / s) The volume of discharged water (m ³ / s) P at the entrance (at) P output (at) T at the outlet of the furnaces (° C) T at the entrance to the KSU (° C) T on the device (° C) The water content at the inlet and outlet of the apparatus (%) entrance exit one 09/19/96 340 0.0012 8 2.2 2.2 45 9 27 6.9 cl 2 09/20/96 315 0.0011 8 2.2 2.2 48 17 32,5 9.0 0.65 3 09/21/96 380 0.0014 5 2.2 2.2 51 eleven 31 31.3 0.28 four 09/22/96 310 0.0011 four 2.2 2.2 55 12 33.5 2.29 0.17 5 09/23/96 320 0.0012 5 2.2 2.2 57 10 33.5 1,5 0.18 6 09/24/96 310 0.0011 5 2.2 2.2 52 13 32,5 4.20 0.58 Mode number 2
A full flow of fluid arriving at the CSN-1 is directed to the filter. Discharge of water 2-3 times a day in manual mode. No. date of The volume of fluid passing through the filter (m ³ / day) Filter flow rate (m / s) The volume of discharged water (m ³ / s) P at the entrance (at) P output (at) T at the outlet of the furnaces (° C) T at the entrance to the KSU (° C) T on the device (° C) The water content at the inlet and outlet of the apparatus (%) entrance exit one 09/27/96 1094 0.0039 7 2.6 2.6 thirty 10 twenty 2.85 cl 2 09/28/96 1186 0.0043 5 2.6 2.6 25 9 17 1,50 cl 3 09/29/96 1083 0.0039 3 2.6 2.6 fifty 9 29.5 3.29 1.16 09/29/96 1083 0.0039 3 2.6 2.6 fifty 9 29.5 4.20 0.43 09/29/96 1083 0.0039 3 2.6 2.6 fifty 9 29.5 3.06 cl

Claims (1)

Installation of field collection, transport and primary treatment of oil and gas, including wells, group metering ladder, separator ladders in the form of horizontal tanks, inside which are installed devices for the destruction of gas-water-oil emulsions, booster pumps, prefabricated tanks, characterized in that devices for the destruction of gas-water-oil emulsions are made in the form of a filter-coalescing package that overlaps the working section of the tank and is composed of a composition of materials of porous-cellular metals and (or) alloys, and (or) porous-cellular polymeric materials with a fixed porous-cellular structure.

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