RU2177490C1 - Method of utilization of asphaltene-resinous-paraffin accumulations and device for its embodiment - Google Patents

Abstract

FIELD: oil production and processing. SUBSTANCE: method includes loading of asphaltene-resinous-paraffin accumulations into vessel l; supplying of hot water with temperature of at least 92 C to vessel l through branch pipe 15; intensive mixing of said accumulations with hot water by means of mixing device 6, and separation of mechanical impurities; sending of said accumulations to sludge trap 14 to melt them under action of hot water; introduction into melt of surfactant - demulsifier in amount of at least 100 g/t of melt; introduction of hot mixture of said accumulation with surfactant into vessel 2 with hydrocarbon fluid (for instance, stock-tank oil, Stabicar) heated up to 50-60 C in ratio of 1:(6-20) wt.p.p., respectively; intensive mixing of mixture under turbulent conditions by mixing device 7; introduction of obtained mixture through branch pipe 18 to main pipeline with crude oil. EFFECT: higher efficiency of method due to provision of full utilization of asphaltene- resinous-paraffin accumulations and rendering mixture of accumulation with hydrocarbon pumpable through pipeline under low temperatures with exclusion of repeated settling of accumulations from mixture. 2 cl, 1 dwg, 1 tbl, 1 ex

Description

 The invention relates to the field of oil production and oil refining, in particular to methods and devices for the disposal of asphalt-resin-paraffin deposits (paraffin deposits) accumulated during the repair of downhole equipment, as well as in tanks and sumps, and can be used in oil producing and oil refining enterprises of the industry.

During the repair of wells associated with the lifting of equipment, a significant number of paraffin deposits are raised along with the equipment. In addition, in the process of cleaning this equipment, a significant amount of paraffin is also collected, which were previously dumped onto the ground, polluting the environment. It should be noted that, on average, during the repair of one well, up to 1000 liters of paraffin and 5-6 m ^{3 of} condensate with oil content up to 750-1000 mg / l were dumped onto the ground.

 A known method for the disposal of oil sludge, according to which the oil sludge is mixed with oil in a mass ratio of 1: 2-4, the mixture is filtered, sedimented and dosed in commercial oil in such an amount that the content of normalized impurities in the commercial oil does not exceed the permissible norms (see Patent RF N 2064962, class C 10 G 31/09, from 1993).

 However, the specified known method is not able to ensure the complete utilization of such wastes as paraffin, due to the complex nature of the dissolution of the latter in a hydrocarbon liquid.

 Closest to the proposed technical solution for the technical essence is a method for utilizing paraffin wax, including melting the paraffin wax, its subsequent dissolution in a hydrocarbon liquid, in particular in oil, and introducing the resulting mixture into marketable oil (see Express information. Transport and Storage Series oil ", M .: VNIIOENG, - 1990, N 5, pp. 44-45).

 However, this known method does not ensure the completeness of disposal of paraffin, since AFS contain a large number of solids, which make them difficult to dissolve in oil.

In addition, the resulting mixture of paraffin and oil by a known method has technologically acceptable rheological properties (pumpability) only at temperatures above +10 ^o C and dramatically reduces the pumpability properties at low temperatures, which can lead to complications in the cold season.

 At the same time, when implementing the known method, the process of repeated deposition of paraffin deposits from commercial oil in the oil collector is not ruled out, which can also lead to complications of the oil preparation process.

 A known installation for the disposal of paraffin wax, including a mixer tank (scraper trap) for accumulating and subsequently mixing the paraffin wax with oil, is equipped with a heater to heat the paraffin wax until the paraffin wax melts in the tank, a device for mixing the paraffin wax with oil (circulation pump ), which ensures the dissolution of molten paraffin deposits in oil and the circulation of the mixture through a mixer tank, as well as a branch pipe for withdrawing the paraffin and oil mixture for its subsequent introduction into the oil collector (see Express Information I. Series "Transport and storage of oil", M .: VNIIOENG, - 1990, N 5, p. 44-45).

 A disadvantage of the known installation is the insufficient efficiency of the disposal of paraffin due to the presence of mechanical impurities in them, which impede the dissolution of paraffin in oil.

 In addition, the known installation provides for the initial accumulation of paraffin in the trap of the scraper and only after that subsequent melting and dissolution of the paraffin in oil. As a result, the low efficiency of the installation due to the significant investment of time.

 Another disadvantage of the known installation is the impossibility of imparting the obtained mixture of dissolved paraffin in oil to the ability to pump through the pipeline at low temperatures, since the paraffin is subjected only to temperature influence (heating, melting) and the subsequent dissolution of paraffin in oil, which is not enough to give the mixture a pumpability at low temperatures.

 The aim of the claimed invention is to increase efficiency by ensuring the complete disposal of paraffin deposits and imparting a paraffin mixture with hydrocarbon liquid pumpability properties through the pipeline at low temperatures, while eliminating the repeated deposition of paraffin deposits from the mixture.

This goal is achieved by the fact that in the known method for the disposal of asphalt tar and paraffin deposits, including their melting, subsequent saturation of the hydrocarbon liquid by them and introducing the resulting mixture into the oil collector, the new thing is that before melting the asphalt tar and paraffin deposits, they are treated with hot water with a temperature of at least 92 ^o C with vigorous stirring in a turbulent mode, while separating the mechanical impurities, and after the melting of the ARPD, a surfactant is introduced into the melt eschestvo (SAW) -deemulgator in an amount of at least 100 g per tonne AFS and subsequent saturation asfaltosmoloparafinistymi hydrocarbon fluid deposits is accomplished by introducing the heated mixture with PAVom these deposits in a hydrocarbon liquid, heated to 50-60 ^o C, in a ratio of 1: 6- 20 parts by weight accordingly, with vigorous stirring in turbulent mode.

 From the patent and scientific and technical literature we do not know how to utilize paraffin, including a combination of these features, which allows us to conclude that the proposed method is new.

 Achieving this goal is ensured, apparently, due to the following.

 Due to the fact that the ARPD, when processed with hot water, is melted and intensively mixed in a turbulent mode, while separating the mechanical impurities and water, a change in the structure of the ARPD is provided, which allows them to be more fully and quickly dissolved in the subsequent hydrocarbon liquid, in particular in oil, and, therefore, will contribute to their more complete disposal.

 And due to the fact that the paraffin is dissolved in a hydrocarbon liquid in a certain proportion, as well as pre-treated with hot water and surfactant, this mixture is provided with unexpected rheological properties, namely: pumpability properties through the pipeline even at low temperatures.

 Due to the fact that surfactants are present in the mixture according to the claimed ratio and the mixture undergoes intensive mixing in a special way, namely, by creating turbulent flows, the formation of a special, finely divided structure of resins, paraffins and asphaltenes in the liquid, which helps to avoid repeated deposition of paraffin from the mixture when the mixture is introduced into the flow of crude oil.

 This goal is also achieved by the fact that in a known installation for the disposal of paraffin, including a mixer tank for saturation of asphalt-resin-paraffin deposits of hydrocarbon liquid, equipped with a heater, a device for mixing and a nozzle for withdrawing the mixture, the new is that the unit is equipped with an additional tank, which is equipped with a heater, a device for mixing, a sludge trap, water inlet and outlet nozzles, as well as flow guides dividing the tank into a filter and settling compartment and communicating with each other, at the same time, a filter is placed in the filter compartment, and catchers are fixed at an angle to the guides, the installation tanks are connected in the upper part by a pipeline, which is in communication with the surfactant dispenser, while flow guides are also installed in the mixer tank.

 The constructive implementation of the installation for the disposal of paraffin in the form of two adjacent containers allows the sequential melting of the paraffin wax, the removal of mechanical impurities from them and the dosed supply of molten paraffin wax to a hydrocarbon liquid for saturation, which ensures complete disposal of the paraffin wax.

The implementation in the tanks installation of flow guides, devices for mixing in a turbulent mode, as well as the presence of heaters allows you to:
in additional capacity:
- intensive mixing of paraffin with hot water and thereby accelerating the melting of solid paraffin;
- separate the solids and debris from the molten paraffin in the filtration zone and send them to the sludge trap;
- enlarge drops of water and separate the water from the molten paraffin deposits in the settling zone;
and in the tank-mixer allows you to:
- create the best conditions for the rapid and complete saturation of hydrocarbon paraffin fluids with surfactants and to create the structure of the resulting mixture with the properties of good pumpability through the pipeline at low temperatures.

 To impart the required rheological properties of the paraffin mixture in a hydrocarbon liquid, a pipeline connecting both capacities of the installation is connected to a surfactant dispenser.

 Thus, the proposed design features of the installation provide, according to the claimed method, high efficiency due to the completeness of utilization of the ARPD accumulated in the tanks for various purposes and giving the ARPD mixture with hydrocarbon liquid pumpability properties through pipelines at low temperatures while eliminating the repeated precipitation of the ARPD from the mixture.

 In the present application for the grant of a patent, the requirement of the unity of the invention is met, since the method and device are intended for the disposal of paraffin. The claimed inventions solve the same problem - ensuring complete utilization and imparting a mixture of paraffin and hydrocarbon liquids with the required rheological properties for introducing the mixture into marketable oil during subsequent pumping through the pipeline even at low temperatures.

 The drawing shows the installation diagram for the disposal of paraffin.

 The installation contains two tanks 1 and 2 connected in the upper part by a pipe 3. In each tank 1 and 2, heaters 4 and 5 are installed, for example, in the form of heating registers, devices 6 and 7 for mixing fluid, made, for example, in the form of propellers with electric drive, and guides 8 and 9 of the stream. Capacity 1 is intended for the melting of paraffin and cleaning them from mechanical impurities and debris. The guides 8 divide the tank 1 into a filter 10 and slop 11 compartments connected to each other. In the filter compartment 10 of the container 1 is mounted a replaceable filter 12, designed to collect floating debris (rags, leaves, grass), and also installed a device 6 for mixing. Moreover, on the flow guides 8, anglers 13 are mounted at an angle, designed to capture mechanical impurities and direct them from the settling compartment 11 to the sludge trap 14.

 Capacity 1 has a pipe 15 for supplying hot fresh water and a pipe 16 for discharging water into the barn.

 The mixer tank 2 of the unit is designed to saturate the melted and refined paraffin deposits of a hydrocarbon liquid. The supply of commercial oil to tank 2 is carried out, for example, through pipe 17, and the mixture of paraffin and commercial oil is drawn through pipe 18. To control the liquid level in tanks 1 and 2, the unit is equipped with level sensors 19 and 20, and temperature sensors use temperature sensors 21 and 22. For introducing a surfactant demulsifier into the melt, the pipeline 3 is in communication with a surfactant dispenser 23. And to ensure a metered discharge of molten paraffin from the tank 1 into the tank-mixer 2 in the tank 1 provides a device for overflow, made, for example, in the form of a float 23 with a flooding drive.

The inventive method in the described device is as follows:
- AFS loaded into the tank 1;
- in the tank 1 through the pipe 15 serves hot water with a temperature of at least 92 ^o C;
- paraffin with hot water is subjected to intensive mixing using a device for mixing 6;
- separate solids and garbage and send them to the sludge trap 14;
- under the influence of hot water, paraffin melts;
- a surfactant demulsifier, for example, grade XT or disolvan, is introduced into the melt in an amount of not less than 100 g / t of paraffin wax;
- further, a hot mixture of paraffin and surfactant is introduced through line 3 into a hydrocarbon liquid heated to 50-60 ^o C (for example: marketable oil, Stabicar) into a container 2, in a ratio of 1: 6-20 wt.h. respectively;
- the mixture is intensively mixed in a turbulent mode using a mixing device 7;
- then the resulting mixture is introduced through pipe 18 into the main pipeline with crude oil.

 An example of a specific implementation.

For the disposal of paraffin wax, the following paraffin wax was used,%:
Asphaltenes - 5.47
Resins - 125.03
Paraffin - 35.9
Mechprimesi - 12.1
Water - 1
Sulfur - 1.82
Chlorides - 140 mg / L
The indicated paraffin deposits brought from the well in the solid state in an amount of about 500 kg were loaded into a tank 1 with a volume of up to 500 l. Then, hot fresh water heated to 95 ^° C was supplied to the container 1 through the pipe 15. The indicated temperature in the tank 1 was maintained by means of a heater 4. The contents of the tank 1 were intensively mixed using the propellers 6, creating a turbulent mode. The solids liberated in this case were separated by catchers 13 and deposited in a sludge trap 14, and floating debris (leaves, grass, etc.) was collected in removable filters 12. Then, a technological sedimentation of the liquid was carried out for 0.5 h. On the surface of the water in the tank 1 a layer of molten paraffin deposits, purified from solids.

Further, these molten paraffin waxes were introduced through pipeline 3 into the mixer tank 2, in which the oil was heated to 60 ^° C, in a ratio of 1:10, respectively. Dosed discharge of molten paraffin in the tank 2 was carried out by means of a float 23 with a flooding drive. At the same time, in the stream of molten paraffin wax, they were preliminarily added either directly to pipeline 3 or to the upper layer of tank 1, the “disolvan” surfactant demulsifier in an amount of 150 g / t of paraffin wax. Then, the mixture in the container 2 was intensively mixed for 20 min using the propellers 7, thereby creating a turbulent regime, after which it was left to stand for 10 minutes. The temperature in the tank 2 was maintained by means of a heater 5. The level sensors 19 and 20 installed in the tanks 1 and 2 monitored the liquid level and thereby excluded uncontrolled liquid overflow from one tank to another. Next, the oil saturated with paraffin, from the tank 2 was pumped through pipe 18 to the feed tank, and the further pumping was carried out according to the technology of the thermochemical installation.

Studies have shown that even at fairly low temperatures (3-5 ^o C), paraffin deposits did not precipitate either in the raw material tank or subsequently in the main pipeline.

 In addition to testing the proposed method and device in the field, laboratory studies were conducted to establish optimal conditions for the implementation of the proposed method. The data obtained are given in the table.

 The data shown in the table show that only with an ASPO: hydrocarbon liquid ratio of 1: 6-20 and with a turbulent mixing mode, the mixture is pumped through the pipeline at low temperatures.

 The proposed method allows you to completely utilize paraffin, thereby eliminating environmental pollution.

 The disposal method is universal for the disposal of both large and small volumes of paraffin. At the same time, the processing process can go on continuously. The plant productivity is 500 kg of paraffin for 1-1.5 hours of work.

Claims (2)

1. The method of disposal of asphaltene-tar-paraffin deposits, including their melting, subsequent saturation of the hydrocarbon liquid with them and introducing the resulting mixture into the oil reservoir, characterized in that before the melting of the asphalt-tar-paraffin deposits, the latter is treated with hot water with a temperature of at least 92 ^{° C.} with vigorous stirring in turbulent mode, while separating the solids, and after the melting of the asphaltene-tar-paraffin deposits, a surfactant, deem, is introduced into the melt an elongator in an amount of not less than 100 g per ton of deposits, and the subsequent saturation of the asphaltene-resin-paraffin deposits of a hydrocarbon liquid is carried out by introducing a hot mixture of these deposits with a surfactant into a hydrocarbon liquid heated to 50-60 ^o C in a ratio of 1: 6-20 wt. h accordingly, with vigorous stirring in turbulent mode.  2. A device for the disposal of asphaltene-tar-paraffin deposits, including a mixing tank for saturating the asphalt-tar-paraffin deposits of a hydrocarbon liquid, equipped with a heater, a device for mixing and a nozzle for withdrawing the mixture, characterized in that the device is equipped with an additional tank that is equipped with a heater, a device for mixing, a sludge trap, and a nozzle water inlet and outlet, as well as flow guides dividing the tank into filtering and settling compartments communicating between y is, thus disposed in the filter compartment filter, and secured to the guide at an angle catcher, the installation vessel connected to the top of the pipe, which is communicated with the dispenser surfactant, wherein the mixing in the vessel as a flow guide installed.

Images