RU1819286C - Method for treatment of oil emulsion stabilized with mechanical contaminants - Google Patents

Abstract

SUMMARY OF THE INVENTION: an oil-soluble demulsifier and a synthetic detergent based on Lotos alkylbenzenesulfonate in amounts of 90-120 g / t and 100-200 g / t, respectively, are introduced into an oil emulsion stabilized by mechanical impurities, respectively, then the emulsion is subjected preliminary sedimentation and discharge of water, then they are heated, an oil-soluble demulsifier and a light gasoline distillate are introduced, mixed, heated and settled. 9 tab.

Description

The method according to the invention relates to the field of oil preparation in the fields, in particular to methods for treating oil emulsions stabilized by mechanical impurities.

The aim of the invention is to reduce material costs by reducing the specific consumption of reagents used.

This goal is achieved by the method of processing the oil emulsion according to the present invention by processing the emulsion, an oil-soluble demulsifier and a synthetic detergent based on alkylbenzenesulfonate Lotus, which are introduced into the emulsion separately in amounts of 90-120 g / t and 100-200 g, respectively t, preliminary sludge and discharge of water and introduction into the oil emulsion after preliminary discharge of water of an oil-soluble demulsifier and a light bezinovy distillate with stirring and heating, followed by sludge .

The study of the processing of oil emulsions stabilized by mechanical impurities was carried out taking into account the natural conditions in the system for collecting well products and the technological parameters of the operation of the oil treatment unit at various specific costs and

00

Yu

go

00

ON

 With

the use of reagents in their various combinations.

It is advisable to use these reagents by dosing at appropriate points, taking into account their various positive effects on oil emulsions stabilized by mechanical impurities. Due to the high content of produced water in oil, an oil-soluble demulsifier is used to pre-destroy oil emulsion in the well collection system . A lotus synthetic detergent is used to transfer solids from the oil zone to the water, to increase the efficiency of the process of separating water from oil and to create conditions for improving the process of deep dehydration and desalting of oil in the oil preparation area in front of the apparatus for preliminary discharge of produced water. Lotus detergent contains 25% sulfonol NP-1 based on alkylbenzenesulfonate, 40% sodium tripolyphosphate, 29.5% sodium sulfate, and additives.

Studies of the effectiveness of the method for processing high viscosity oil emulsions at the preliminary water discharge stage were carried out in laboratory conditions at a temperature of 10 ° C. For research, a sample of a highly viscous and sour crude oil emulsion stabilized by mechanical impurities mined in the Jalilneft oil and gas production unit was taken. The emulsion was characterized by a water content of 78%, salts of 55,000 mg / L, iron sulfide 1,680.8 mg / L, mechanical impurities of 1.69%, emulsion viscosity at 10 ° C 846.5 MPa, s, emulsion density at 10 ° C 1011 kg / m3.

In a sample of oil emulsion with residual bound water in an amount at a temperature of 10 ° C after separation of free water, a water-soluble demulsifier disolvan 4411 and an oil-soluble demulsifier disolvan 4490 were introduced separately for comparison at different specific rates. In this experiment, the process of pre-fracturing persistent oil emulsion in a well production system was investigated. When using a water-soluble demulsifier, disolvan 4411, the residual content of solids in oil was 1.34%, and when using an oil-soluble demulsifier, disolvan 4490 was 1.21%. After the introduction of demulsifiers, the emulsion samples were mixed on a laboratory stirrer with a reciprocating motion for 2 hours. Then, the samples were sedimented under static conditions for 4 hours (the process of pre-discharge of produced water was simulated). After sediment and separation

free water in oil samples was determined by the residual water content. The research results are shown in table 1.

The table shows that when using a water-soluble demulsifier

disolvan 4411 with a specific consumption of 160-200 g / t, oil is obtained with a residual water content of about 10% (experiments 9, 10, 11), i.e. in this case, a significant consumption of demulsifier is required, which

not economically viable.

When using oil-soluble demulsifier disolvan 4490 with a specific flow rate of 90-120 g / t is achieved oil with a residual water content

less than 10.0%, i.e. the emulsion breaks down somewhat more efficiently and at lower specific costs of the demulsifier (experiments 14, 15, 16.17).

Then, oil samples with a residual water content (experiments 14, 15, 16, 17) were examined to determine the optimal process of dehydration and desalting of oil with various options for the additional use of other reagents.

Options.

1. Oil samples at a temperature of 70 ° C without additional introduction of demulsifiers were put on sediment in static conditions for 2 hours (dehydration process

oil). The viscosity of the emulsion at a temperature of 70 ° C is 26.3 MHPa-s. After the lag time has elapsed and the released free water has separated from the oil, the residual water content of the dehydrated oil is determined. The research results are shown in dehydrated oil. The research results are given in table.2.

It can be seen from the data in Table 2 that in all cases of the experiment, deep oil dehydration is not achieved. The residual water content in dehydrated oil is much greater than 0.5%.

Then, fresh washing water in the amount of 5% of the volume of oil was introduced into oil samples with a residual water content, the samples were mixed for 5 minutes and put to sediment in static conditions for 2 hours at a temperature. 70 ° C (simulated oil desalination). After the lag time and separation of the released free water from the oil, the residual content of water and salts in the desalted oil was determined.

The research results are given in table.3. .

From the data in table 3. It is seen that in all cases of the experiment, deep desalination of oil is not achieved. The residual water content is much greater than 0.5% and salts more than 40-100 mg / l. Commodity oil with this amount is sold in the third group with fines of 90 kopecks. per ton in accordance with GOST 9965-76.

2. An oil-soluble demulsifier disolvan 4411 or an oil-soluble demulsifier disolvan 4490 with various specific flow rates were additionally introduced into oil samples for comparison. The samples were mixed on a laboratory stirrer with a reciprocating movement for 2 hours, and they were sedimented under static conditions at at a temperature of 70 ° C (the oil dehydration process was simulated). After the lag time has elapsed and the released free water has separated from the oil in the dehydrated oil, the residual water content is determined. The research results are shown in table 4.

The viscosity of the emulsion after additional administration of a water-soluble demulsifier, disolvan 4411 at a temperature of 70 ° C is 23.4 MPa-s. The viscosity of the emulsion after additional administration of an oil-soluble demulsifier, disolvan 4490 at a temperature of 70 ° C is 19.6 MPa-s. The residual content of solids in oil samples with the additional introduction of disolvan 4411 was 1.03%, and with the introduction of disolvan 4490-0.93%.

From the data table. 4 shows that in. In all experimental cases, deep oil dehydration is not achieved. However, when an oil-soluble demulsifier is used, disolvan 4490, the residual water content in the oil is significantly reduced, especially at a specific flow rate of 10 g / t or more. Therefore, at this specific consumption, the use of disolvan 4490 in this case should be recognized as technologically and economically more profitable. The residual water content in oil is less than 1.0% (see experiments 25, 26, 27, 28).

Then, fresh flushing water in the amount of 5% of the volume of oil was introduced into all samples of dehydrated oil. The samples were mixed for 5 minutes and placed in sediment at a temperature of 70 ° C for 2 hours (the process of desalting the oil was simulated). After the lag time and separation of the released free water in the desalted oil, the residual

water and salt content. The research results are given in table.5.

It can be seen from the data of Table 5 that in all cases of the experiment, the production of deeply desalted oil is not achieved. The residual salt content in oil is more than 40-100 mg / l and water is more than 0.5%. Commodity oil of this quality in accordance with GOST 9965-76 is dealt with fines of 90 kopecks. for every ton.

For further studies, the options were selected (experiments 25, 26, 27, 28) from Table 4 with a specific consumption of oil-soluble demulsifier disolvan 4490 equal to 10 g / t of oil, as the most acceptable technologically and economically. At a specific flow rate of the demulsifier of 4490 5-8 g / t of oil, the desalting of oil is unsatisfactory, and an increase in the specific consumption of the demulsifier to 20 g / t does not significantly improve the process of desalting of oil.

3. In order to increase the depth of destruction of the persistent oil emulsion and reduce the viscosity of the emulsion, a light gasoline distillate was added to the oil samples at various specific rates. The research results are given in table.6. The temperature of the oil dehydration process is 70 ° C.

It can be seen from the data in Table 6 that, after the addition of light gasoline distillate, the viscosity of the emulsion significantly decreases. At the same time, the residual water content in the dehydrated oil at a temperature of 70 ° C is reduced in comparison with other options (see Tables 2, 4). The residual content of solids in dehydrated oil was 0.78%. In these embodiments, the production of deeply dehydrated oil is also not achieved, the residual water content in the oil is more than 0.5%. However, at a specific distillate flow rate of 20 l / t oil and more, the residual water content in the dehydrated oil is slightly less. The consumption of gasoline distillate, equal to 20 l / t (experiments 9, 10, 11, 12), should be considered optimal, since a decrease in the distillate consumption leads to an increase in the water content, while an increase in the distillate consumption leads to a substantial decrease in the water content, however, it leads to an increase in material costs.

Then, studies were carried out on the process of desalting the oil samples from Table 6 with the addition of fresh washing water in an amount of 5%. The research results are given in table 7. The process temperature is 70 ° C.

From the data of Table 7 it is seen that the production of deeply dehydrated and desalted oil is not achieved in any of the experiments. Nevertheless, at a specific distillate consumption of 20 l / t of oil or more, the process is more efficient, the salt content in the oil decreases. Experiments 9, 10, 11, 12 with a specific distillate consumption of 20 l / t should be recognized as the most optimal variant of the oil desalination process according to Table 7. at a lower flow rate, the residual content of water and salts in the oil increases, and with an increase in the flow rate, a significant decrease in the content of water and salts in the oil does not occur.

4. As shown by studies, in all cases, the production of deeply dehydrated and desalted oil is not achieved. This is due to the fact that the high content of solids in oil significantly inhibits the process of adsorption of a demulsifier on the surface of water globules and the destruction of armor shells on them. Scientific research carried out in this direction has shown the need to transfer solids from the oil phase to the aqueous phase to intensify the process of oil dehydration.

For this purpose, various detergents (sulfonol-40, sulfonate ML-72, wetting agent SV-102, Lotus) were tested, wm, at appropriate specific costs, they effectively wash the mechanical impurities from the oil phase of the emulsion into the water phase and create favorable conditions for intensification the process of deep dehydration and desalting of oil.

In order to reduce the volume of tabular material, for example, in this case, we present the results of a study of the process of pre-discharge of produced water with the additional use of Lotus detergent reagent at its various specific consumption before the apparatus for preliminary discharge of produced water. In this case, the specific consumption of oil soluble demulsifier disolvan 4490 in the well production collection system was 90-120 g / t oil (see experiments 14, 15, 16, 17 of Table 1). The results of studies on the effectiveness of Lotus detergent reagent for washing out mechanical impurities are given in Table 8. In this case, the residual content of solids in the oil after the apparatus for preliminary formation water discharge decreased from 1.21% to 0.008%. The process temperature is 10 ° C.

It can be seen from the data in Table 8 that the use of Lotus detergent significantly intensifies the process of separating water from oil. According to research

100-200 g / t of oil should be recognized as the experimental specific consumption of Lotus, as an increase in flow rate does not significantly reduce the residual water content in the oil.

5. In order to determine the effectiveness of using Lotus on the process of deep desalting of oil at the installation, various unit costs were taken in front of the apparatus for experiments.

preliminary discharge of produced water according to table 8. In this case, the optimal specific consumption of oil-soluble. demulsifier disolvan 4490 in the system of collecting wells is 90-120 g / t of oil (experiments 14,

15,16,17 according to table 1), the optimal specific consumption of oil-soluble demulsifier disolvan 4490 and light gasoline distillate after the apparatus for preliminary discharge of produced water, respectively

equal to 10 g / t of oil (experiments 25, 26, 27, 28 according to Table 1) and 20 l / t of oil (experiments 9,10,11,12 according to Table 6). The research results are given in table.9. The process temperature is 70 ° C, the flow rate of fresh wash water is 5.0%.

It can be seen from the data in Table 9 that when using Lotus washing reagent in front of the apparatus for preliminary discharge of produced water in order to transfer mechanical impurities from the oil phase to vodka, deep dehydration and desalination of oil is achieved, i.e. the residual water content in oil is not more than 0.5% and salts 40 mg / l.

Claims (1)

Gain Formula A method of treating an oil emulsion stabilized by mechanical impurities, comprising introducing a demulsifier into it, preliminary sediment and discharge water, the introduction of a demulsifier, mixing and heating, sludge, characterized in that, in order to reduce the consumption of the reagent, an oil-soluble demulsifier is used, moreover, a synthetic detergent based on alkylbenzenesulfonate Lotus, a demulsifier and a synthetic one are additionally introduced into the oil emulsion detergent is administered separately in amounts of 90-120 g / t and 100-200 g / t, respectively, and after a preliminary discharge, a light gasoline distillate is further added to the oil emulsion. 1819286 10 table 1 table 2 Table 3 Table 4 Continuation of the table. 4 Table 5 Continuation of the table. 5 Table 6 Table 7  Table 8 nineteen 1819286 Table 9