RU2636313C1 - Oil purification plant - Google Patents

Abstract

FIELD: oil and gas industry.SUBSTANCE: invention relates to the plant for oil purification including a flow tubular settling separator, branch pipes for supply of oil and washing liquid, a mixer for oil and washing liquid which is characterized by that oil and washing liquid supply branch pipes are connected to the mixer installed in front of the settler, in the mixer the jets of oil and washing liquid are directed towards each other with equal cross-section at the point of collision of jets, the and branch pipe for supplying the mixture of oil and washing liquid from the mixer to the settler is in the form of a horizontal slit diffuser with a width equal to inner diameter of the horizontal tube of the tubular settling separator. The invention is intended for purification of oil contaminated with floating liquid medium, for example, water and can be used for the preparation of oil at fields and oil refineries and in any industry where such a need arises.EFFECT: application of the plant makes it possible to increase oil purification efficiency by increasing the degree of oil mixing with washing liquid and creating conditions for more efficient gravitational separation of oil from washing liquid.1 dwg

Description

The invention is intended for the purification of liquids, such as oil, contaminated with a floating liquid medium, such as water, and can be used in the preparation of oil in oil fields and refineries and in any industry where such a need arises.

A known installation for oil dehydration (RF patent No. 2077918, class 6 B01D 17/028, publ. 04/27/1997). The installation includes a housing with a compartment for oil dehydration, a nozzle supplying an oil-water mixture from one end of the housing, and nozzles that discharge gas, water, oil, oil and water level controls, transverse partitions in the middle of the section of the housing, forming steps with the upper and lower edges of the partitions .

The disadvantage of this installation is the decrease in efficiency when cleaning oil from a low water content, since in this case, the stepwise placement of partitions along the upper edge of the partitions does not provide oil overflow through the top of all partitions until the settled water reaches the calculated level of the oil-water interface. Thus, in this case, for a long time, the installation operates in off-design mode in terms of performance.

A known installation for the purification of oily wastewater (RF patent No. 2133222, class C02F 1/40, publ. 07.20.1999). The installation includes a flow-through tubular sump separator, nozzles for supplying purified water, a water trap, level controllers, nozzles for removing purified water and accumulated oil and gas, and the supply of purified water is carried out by sprayers placed above the oil level. Purification of contaminated water is carried out by passing oily wastewater through an oil layer.

The disadvantage of this installation is the lack of effective mixing of contaminated water with oil. When spraying oily wastewater, droplets of varying degrees of dispersion are formed. As a result of this process, large droplets of oily wastewater falling at a sufficiently high speed, penetrating the oil layer, partially crush it into small droplets of oil and carry these drops of oil down with them. As a result of this process, in the vertical direction, not only the oil contained in the oil-containing wastewater floats in the sumps, but also the oil entrained by the drops of oil-containing wastewater from the oil layer. In this case, the volumetric concentration of oil, in comparison with its initial content in oily wastewater, increases, which means that the rate of ascent of oil droplets decreases, especially since they move in countercurrent flow with the stream of treated wastewater moving from top to bottom. This circumstance requires a longer time for the purification of wastewater from oil contaminants when they are high, which reduces the productivity of the installation in terms of the volumetric flow rate of oil-containing wastewater or the use of wastewater with a low content of oil pollution.

A known installation for oil refining (RF patent No. 2118198, class B01D 17/028, publ. 08.28.1998). The installation includes a flow settler with baffles, the upper edges of which are located at the same level, a compartment for accumulating refined oil, pipes for supplying refined oil, drainage of oil, water and gas, regulators of oil and water levels, and a compartment for refined oil is formed by the last baffle made blind from the bottom, the pipe for supplying the oil to be cleaned is placed with its open end up at the level of the lower edge of the first partition, the pipe for discharging settled water is located in the lower part of the sump in front of the last partition and connected to a water trap, and in the upper part of the sump is placed a fresh water atomizer. Purification of contaminated oil is carried out by spraying a flushing liquid - pure water over a layer of oil.

The disadvantages of this installation are the ineffective mixing of oil with a washing liquid, since large drops of water, impacting the oil layer, cause the formation of oil drops, which are carried away by the water drops deeper, which reduces the efficiency of the mixing process.

The closest to the proposed technical solution installation for oil refining (RF patent No. 2221620, class B01D 17/00, publ. 20.01.2004). The installation includes a flow settling tank-separator, nozzles for supplying oil and washing liquid, an oil and washing liquid mixer, the nozzles for supplying oil and washing liquid inside the settling tank placed one inside the other, and the inner nozzle for supplying washing liquid is perforated and with a plugged end.

The disadvantage of this installation is the low efficiency of the process of mixing contaminated oil and flushing fluid. In a known technical device in the annulus of the mixer, the oil is flushed and refined with mixing jets of washing water. With a linear size of the mixer of the order of 1 m and a speed of the mixture in the annular gap of the mixer of the order of 1 m / s during the passage of the mixture of the mixer equal to 1 s, the indicated processes of washing and refining the oil can only begin. With the intensification of the mixing process, by increasing the speed of the medium in the annulus, the passage time of the mixer mixture will be reduced. With a decrease in the velocity of the medium in the annulus, the degree of mixing of the jets of washing water and oil will decrease. In all cases, the mixer rinsing and refining processes are just beginning. The open end of the mixer nozzle is located at a height of mid-height of the sump, and, according to the attached drawing, a vertically directed jet of washing water and oil first passes sequentially through the layer of already separated washing liquid, and then through the layer of already separated oil and due to the ejection action carries these medium into a horizontal tube of a tubular sump, which reduces the efficiency of the subsequent separation of oil and washing liquid. Thus, the used oil and flushing fluid supply system to the mixer leads to the involvement in the process of additional mass of already refined oil and spent flushing water, which reduces the technological efficiency of the installation.

The objective of this technical proposal is to increase the efficiency of the oil refining process, which reduces operating costs.

The technical result that leads to the solution of the problem is to increase the efficiency of oil refining by increasing the degree of mixing of oil with flushing fluid and creating conditions for more efficient gravitational separation of oil from flushing fluid.

The specified technical effect is achieved by the fact that in a known installation for oil purification, including a flowing tubular sump separator, nozzles for supplying oil and washing liquid, an oil and washing liquid mixer, the oil and washing liquid nozzles being connected to a mixer installed in front of the sump, in the mixer, the jets of oil and washing liquid are directed towards each other with an equal cross section at the point of collision of the jets, and the nozzle for supplying a mixture of oil and washing liquid from the mixture Itel in the sump is made in the form of a horizontal slot diffuser with a width equal to the inner diameter of the horizontal pipe of the tubular sump separator.

Pre-mixing of oil and flushing liquid in a mixer (homogenizer), installed in front of the place of supply of the mixture to the sump, provides highly efficient mixing of oil with flushing liquid before the process of separation of media. To intensify the mixing process in the mixer, the jets of oil and flushing fluid are directed towards each other with an equal cross section at the point of collision of the jets. In a head-on collision of jets of oil and flushing fluid with an equal cross-section of jets at the site of their collision, the mechanism of mutual mixing of both fluids along the entire contact plane of their interaction is maximally realized.

The mixer, along with the fulfillment of the main function, acts as a hydrodynamic damper, smoothing the pulsations that occur during separate pumping of oil and flushing liquid into the mixer installed directly inside the separator. This creates favorable conditions for the process of gravitational separation immediately after the mixture enters the flow-through tubular sump-separator.

The presence of a mixer in which contaminated oil is mixed to a homogeneous state with the washing liquid reduces the volume fraction of contaminants, which allows to increase the speed of oil ascent, and therefore, increases the technological efficiency of the process of oil purification from pollution.

The pipe for supplying the mixture to the tubular sump separator is made in the form of a horizontal slot diffuser with an outlet section width equal to the inner diameter of the horizontal pipe of the tubular sump separator. In this case, the process of cleaning the mixture from contaminants begins immediately after the mixture of oil and washing liquid enters the horizontal pipe of the tubular sump separator, since the laminar flow regime of the mixture layer is realized, in which the most efficiently the gravitational separation of the mixture components occurs.

The drawing shows the installation, which includes a flow-through tubular sump-separator 1, a water seal 2, a pipe for supplying oil 3, a pipe for supplying washing liquid 4, a pipe for supplying purified oil 5, a pipe for removing used washing liquid 6, a pipe for removing gas 7 , mixer (homogenizer) 8, horizontal slot diffuser 9, oil level sensor 10 and gas pressure regulator 11.

The installation must be installed in a horizontal position stationary or performed in a mobile version. In both cases, the installation must be connected by pipelines to the corresponding nozzles. Installation works as follows. The oil to be cleaned is fed into the mixer 8 through the pipe 3, and the washing liquid is fed into the mixer 8 through the pipe 4. The mixed mixture of oil and washing liquid from the mixer 8 is fed through a horizontal slot diffuser 9 to the tubular separator 1. Thereafter, as the mixture accumulates in the sump, the mixture layer moves along the upper horizontal pipe of the tubular sump separator, and the refined oil flows into the far right vertical compartment of the tubular sump separator. When moving along the upper horizontal pipe of the sump, gravitational separation of oil and flushing fluid occurs. The flushing liquid settles in the intermediate vertical compartments and then moves to the lower part of the sump, from where it is removed through the pipe 6 from the tubular sump-separator 1. The level of the oil-washing liquid interface is maintained by a water trap 2 or any other level control device. The selection of oil is regulated by the oil level sensor 10, according to the testimony of which the purified oil from the far right vertical compartment is removed through the pipe 5. The gas released from the oil is removed through the pipe 7 through the pressure regulator 11.

The proposed installation for oil refining can be used in the purification of oil from salts, hydrogen sulfide, water and, with appropriate retrofitting, and to remove mechanical impurities.

Claims (1)

Installation for oil refining, including a flowing tubular sump separator, nozzles for supplying oil and flushing fluid, an oil and flushing fluid mixer, characterized in that the piping of oil and flushing fluid is connected to a mixer installed in front of the settling tank in an oil jet and flushing mixer liquids are directed towards each other with an equal cross section at the point of collision of the jets, and the nozzle for supplying a mixture of oil and washing liquid from the mixer to the sump is made in the form of horizontally th slot diffuser with a width equal to the inner diameter of the horizontal pipe of the tubular sump separator.

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