SU1761187A1 - Unit for processing resistant, high-viscosity oil emulsions - Google Patents

Abstract

The invention relates to the preparation of oil in the fields, in particular, to installations for the treatment of highly viscous resistant oil emulsions. The aim of the invention is to increase the efficiency of the treatment process for highly viscous resistant oil emulsions. The installation contains the first gas separation stage 1 the second gas separation stage 2 pipelines 3 tank 4 for preliminary discharge of produced water with a device 5 for high-speed emulsion injection into the water zone and machining with a perforated pipe 6, pumps 12 and 13 for feeding intermediate emulsion layers, pumps 14 and 15 for pumping of pre-sludge-free and commercial oil, respectively, furnace 16, tubular drop-formers 17 and 18, settling tanks 19 and 20, devices 21 and 22 for introducing fresh wash water second conduit 23, dopopnitelnich treatment vessel 24 with arranging PTO 25, a reservoir 27 for oil heading marketable oil metering unit 29, a reservoir 29 for cleaning waste water pump 31 January yl 1L

Description

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The invention relates to the preparation of oil in fields, in particular, to installations for the treatment of highly viscous, resistant oil emulsions.

The experience of oil preparation in the fields in recent years has shown that the processes of oil dehydration and desalting in installations have become significantly more complicated. This is associated with an increase in the content of finely dispersed produced water and mechanical impurities in the oil, as well as with many physicochemical effects occurring during the production and collection of well products under conditions of using various chemical reagents. To enhance oil recovery of the layers, wells, hydrophobic emulsion acids, are treated. solutions, etc., oil production intensifiers are used, reagents for controlling paraffin and salt deposits in collection pipelines, various inhibitors are used corrosion factors In all these cases, the mud deposits that accumulate in the pipelines are washed out and high-viscosity jelly masses are formed in the production of wells. The problem of oil preparation is even more aggravated due to an increase in the quantitative content of various mechanical impurities and iron sufida in pro

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well production. Ferric sulphide along with other natural emulsifiers, mud deposits and mechanical impurities enters the tanks and settling apparatuses. The complex of these inclusions accumulates in the process equipment and forms a dense intermediate emulsion layer, which prevents the process of sedimentation of water droplets. For this reason, oil treatment facilities often get out of the normal technological mode of operation, which results in the delivery of low quality commercial oil. This type of oil emulsions are emulsions with complicated rheological properties. In order to maintain a normal technological mode of operation at oil treatment plants, usually from technological devices, periodically or permanently intermediate emulsion layers are dumped into oil traps or into tanks specially allocated for this chain, where they are stored as waste products. All this leads to a decrease in the volume of delivery of commercial oil.

The closest in technical essence to the present invention is a plant for processing intermediate emulsion layers and trap oil. The installation includes a raw material tank with a device for machining the emulsion by introducing it into the oil zone, an oil heater, an electric dehydrator and settling tanks for dewatering and desalting oil, commercial oil tanks, a pipeline for returning warm drainage water, a pipeline system connecting the upper oil zone of the raw material. tank with supply pipe for field emulsion, wastewater treatment equipment, pumps for oil supply and dedmulgator.

This installation does not ensure the effective destruction of resistant oil emulsion due to the absence of a process of repeated mechanical treatment accumulating resistant intermediate emulsion layers in process tanks and settling apparatuses. For this reason, when processing resistant oil emulsion (viscosity at 20 ° С, 1764 eats, density 941 Kr / MJ, oil water content 65%, mechanical impurity content 1.2% and iron sulfide 61 mg / l, droplet water sizes 1 ... 30 µm), the residual water content in the prepared oil was at least 1.0% and salts of 1736 mg / l. The process temperature is 80 ° C, the specific consumption of the reagent composition is: di-solvan 4411 (300 g / t), sulfanol (850 g / t) and

light gasoline distillate (50 g / t). Commercial oil with this quality is delivered with fines of 90 kopecks per ton of oil in accordance with GOST 9965-76.

The aim of the invention is to increase the processing efficiency of highly viscous resistant oil emulsions.

For this, the installation includes gas separation stages, a reservoir for pre-discharge of produced water with a device for mechanical destruction of the emulsion, a device for introducing a demulsifier and fresh wash water, a furnace for heating oil, settling tanks for oil decontamination and desalting stages, tubular droplets, tanks commercial oil and for wastewater treatment. return pipe of warm drainage water to the head of the technological process,

0 recirculation system, pumps for oil and water.

The reservoir for the preliminary discharge of formation water is provided with a recirculation system that connects through

5 through the pump area of the intermediate emulsion layer with a pipe supplying field emulsion. The plant is equipped with an additional process tank with a device for the mechanical destruction of the emulsion, installed after the settling tanks of the oil desalting stage, the upper part of which is connected to the zone of the intermediate emulsion layer

5 of the additional process tank, the oil in the zone of the latter is connected to the tank of commercial oil, and the water to the tank from the wastewater treatment tank, and the intermediate zones

The 0 emulsion layers of the settling tanks of the dewatering and desalting stage of oil and the wastewater treatment tank are connected to the supply line emulsion through a pump.

5 The drawing shows a schematic flow diagram of the installation.

It consists of the first stage of separation of gas 1, the second stage of separation of gas 2. pipeline 3 to enter the field

0 emulsion, reservoir 4 for preliminary discharge of formation water with a device 5 for high-speed emulsion injection into a water zone and mechanical treatment with a perforated pipe 6 for removal of an intermediate emulsion layer, devices 7-11 for supplying demulsifiers, pumps 12 and 13 for supplying intermediate emulsion layers, pumps 14 and 15 for pumping pre-dried and commercial oil, respectively, furnace 16 for heating

emulsions, tubular droplets 17 and 18, sumps 19 and 20 for deep dehydration and desalting of oil, respectively, devices 21 and 22 for injecting fresh wash water, a process pipe 23 for draining desalted oil from sumps 20, an additional process tank 24 with a device 25 for speed input and machining of pre-desalted oil, pipeline 26 for transferring oil from tank 24 to tank 27 for commercial oil, metering station 28 for commercial oil, cutting A tank 29 for wastewater treatment, a pipeline 30 for transferring wastewater from a tank 24 to a tank 29, a pump 31 for pumping treated wastewater to a reservoir pressure maintenance system, a pipeline 32 for converting wastewater from a tank 4 to a tank 29, a pipeline 33 for inlet warm drainage water to the intake of the pump 12, the process pipe 34 to enter the intermediate emulsion layer from the tank 4 into the pipe 3 of the field emulsion of the process pipe 35 to enter the intermediate emulsion layers from toynikov 19 and 20 and the reservoir 29 into the conduit 3 fishing emulsion.

The installation works as follows.

The highly viscous oil-emulsion resistant to breakage (viscosity 2165 eats and has a density of 958 kg / m3 at 20 ° С, oil water content is 58%, mechanical impurities content is 1.4% and iron sulfide is 150 mg / l, the size of the formation water droplets is 1 ... 20 µm) using a dosing device 7, a demulsifier disolvan 4411 is injected into the well production collection system at the rate of 120 g / ton of oil. The pre-destroyed emulsion enters the separators 1 of the first stage of separation, then the 2 stage of separation, from where the gas separated from the oil is directed to the compressor stations, and the oil on the emulsion in the amount of 8000 tons per day through the pipeline 3 through the nozzles of the device 5 with high-speed jets with rotational movement is introduced into the water zone 36 of reservoir 4 with a volume of 5000 m. At the same time, under the action of centrifugal force, additional mechanical destruction of the injected emulsion is carried out, the process of separating water and mechanical impurities from oil and their sedimentation to the bottom of the tank 4 is intensified. A stable intermediate emulsion layer 37 in the amount of 15 m3 / h HeiipepbiBHo together with the introduced via

a dosing device 10 with a reagent composition consisting of a demulsifier disolvan 4411 (150 g / t of oil) and sulfanol (450 g / t of oil) and warm drainage water 33

in an amount of about 30 m / h discharged from the settling tanks of the 19th stage of oil dehydration and the settling tanks of the 20th stage of oil desalting, is pumped into the pipeline by means of a pump 12 via the process pipeline 34

0 3 and, together with the production emulsion, is fed into the tank 4. At the same time, due to the high-speed introduction of a mixture of these emulsions through the nozzles, rotational movement and the effect of centrifugal force create the perturbation of the intermediate layer and the mechanical destruction of the injected emulsion, intensifies the process of separating water droplets and mechanical impurities from oil and their subsidence to the bottom

0 tank 4. The process of recirculation of the intermediate emulsion layer 37, depending on the intensity of the accumulation process in tank 4, is carried out either continuously or periodically.

5Pre-dehydrated oil in

150 m / h with a residual water content of not more than 5% from the upper zone of the tank 4, together with the light gasoline distillate 8 that was additionally introduced using the dosing device 8 in the amount of 20 g / t of oil, is fed into the furnace 16 (type PTB-10 the design of the Saratovneftegaz Combine Design Bureau), where it is heated to 80 ° C. Heated oil

5, the emulsion is introduced into a two-section tubular droplet 17, where mass transfer processes and the consolidation of water droplets take place (Rei 30000, movement time 1.5 minutes; Re — 10,000, movement time 0 and 3 minutes). The emulsion processed in the dropper is introduced into the settling tanks 19, where the emulsion is separated into deeply dried oil and water at a sludge residence time of not less than 2 hours. Deeply dried oil with a residual water content in the range of 0.3 ... 0.8% together 5% of the volume of oil heated to a temperature of 50 ° C is introduced into the single-section tubular dropper 18, where saline droplets of produced water are drained with drops of fresh wash water and Ukrainian replenishment (Re 35000, time of movement, 2.5

min) The oil processed in the dropper with fresh wash water is introduced into the settling tanks 20, where, at a time of at least 2 hours, the oil is separated into previously desalted

five

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oil and water. Separated from the heat oil from the drainage water from the sump 19 and 20 through the pipeline 33 is directed to the intake of the pump 12.

Pre-desalted oil with a water content of not more than 1% and salts of 150-350 mg / l along with 2% added fresh washing water 22 and a demolgator disolvan 4411 at the rate of 50 g / t of oil from the process line 23 where mass transfer takes place the processes, through the nozzles of the device 25, are introduced into the intermediate layer 39 above the interphase level of the oil-water by an additional technological reservoir 24 by high-speed jets of rotational motion. At the same time, under the action of centrifugal force, additional Mechanical destruction of the emulsion, intensifies the processing with demulsifier and fresh wash water, separates saline water droplets and mechanical impurities from the oil and deposits them to the bottom of the tank 24. The required processing time for the emulsion is at least 20 hours. The need for an additional process tank 24 is associated with physical complexity - chemical and rheological properties of emulsions. Desalted oil 40 from the upper zone of reservoir 24 via pipeline 26 enters the tank 27 of commercial oil, from which oil with a water content of not more than 0.5% and salts 40 ... 100 mg / l by pump 15 through metering station 28 is delivered to the oil pipeline control . The surrender of commercial oil in quality corresponds to the highest and first groups of GOST 9965-76.

Accumulating resistant intermediate emulsion layers from settling tanks 19 and 20 and mechanical oil contaminated filtering layer from reservoir 29 in an amount of 10 m3 / h together with the reagent composition injected consisting of 4411 disolvan (150 g / t oil) and sulfanol ( 350 g / ton of oil), by pump 13 via process line 35, where mass transfer processes are carried out, are fed into pipeline 3 of the field emulsion, through which they are introduced into process tank 4 for machining.

Drainage water 41 discharged from process tanks 4 and 24 through pipelines 30 and 32 through filtering oil layer 42 enters tank 29, where wastewater is cleaned from oil products and mechanical impurities due to their transfer into the volume of oil phase. Purified sewage 43 pump 31

sent to a reservoir pressure maintenance system.

The specific consumption of the demulsifier disolvan 4411 in terms of the entire volume of oil produced at the plant is 220 g / t, sulphanol — 150 g / t and light gasoline distillate — 20 g / t of oil.

The unit was tested at the NGDU Jalilneft PO Tatneft. 0Application of the proposed installation

allows:

- reduce the specific consumption of the demulsifier disolvan 4411 from 300 g / t (prototype) to 220 g / t;

5 - to reduce the specific consumption of sulfanol from 850 g / t (prototype) to 150 g / t;

- reduce the specific consumption of light gasoline distillate from 50 l / t (prototype) to 20 l / t;

0- reduce the water content in the product

oil from 1.0% (prototype) to 0.5%;

-reduce the salt content in the crude oil from 1736 mg / l (prototype) to 40-100 mg / l;

5- get the economic effect for

through the elimination of fines for the delivery of high-quality commercial oil in the amount of about 1.0 million rubles a year with an installation capacity of 1.2 million tons / year for oil.

Claims (1)

Formula of invention A plant for processing high-viscous resistant oil emulsions, comprising gas separation stages, a reservoir for preliminary discharge of formation water from 5 a device for the mechanical destruction of the emulsion, a device for introducing the demulsifier and fresh washing water, a furnace for heating the oil, sumps of the stages of dehydration and desalting of oil, 0 tubular droplets, tanks for marketable oil and sewage treatment; pipeline for returning warm drainage water to the process head; pumps for supplying oil and water, so that, in order to increase the efficiency of the process, the tank for pre-discharge of produced water is provided with a recirculation system connecting the intermediate zone through the pump 0 emulsion layer with pipeline supplying emulsion layer, the installation is equipped with an additional process tank with a device for mechanical destruction of the emulsion installed 5 after the settling tanks of the oil desalting stage, the upper part of which is connected to the zone of the intermediate process tank, and the oil for the last zone it is connected with the tank of commercial oil, and the waters with the tank with the wastewater treatment tank, and the zones of location of the intermediate emulsion layers of the settling tanks 37 dewatering and desalting the oil and the wastewater treatment tank by means of a pump are connected to the pipeline emulsion supply.