SU1766943A1 - Method of high-viscous desalinated oil emulsion dehydratation - Google Patents

Description

The invention relates to the field of the oil industry, in particular to the technological processes of dehydration of high-viscosity oil emulsion in the fields.

The known method of dehydration of high-viscous oil is based on the destruction of resistant water-oil emulsion by heating, the introduction of a demulsifier reagent, warm drainage water and subsequent sediment 1.

The method is not efficient enough to dehydrate a highly viscous desalinated emulsion with a high content of mechanical impurities, such as bitumen, as it requires high material costs due to the high heating temperature, high consumption of expensive demulsifier, and the need to build several dewatering stages.

The closest in technical essence to the proposed method is

dewatering a highly viscous desalinated oil emulsion by heating it, introducing an oil-soluble demulsifier based on a block copolymer of ethylene and propylene oxides and a diluent, mixing and sludge 2.

The disadvantage of this method is the increased residual water content in a dehydrated high viscosity desalinated emulsion with a high content of mechanical impurities due to the low rate of sedimentation of desalinated water droplets and accumulation of resistant intermediate layers with a high content of mechanical impurities in process equipment.

The purpose of the invention is to reduce the residual water content in the oil.

The goal is achieved by the proposed method of dehydrating a highly viscous desalinated oil emulsion by heating it, introducing an oil-soluble demulsifier based on block copolymer

about

about

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pa of ethylene and propylene oxides and diluent, mixing and sludge.

New is the fact that water-soluble de-emulsifier based on block copolymers of ethylene and propylene oxides and salt water are additionally added to oil in the following ratio of injected components,% of the volume of oil emulsion: h

Water soluble

deemulater0.02-0.03

Oil soluble

Deem Ulgator 0.03-0.05

Thinner 30-50

Saline water 10-15

The proposed method is carried out in the following sequence.

Highly viscous desalinated emulsion with a high content of mechanical impurities is preheated to 50 ° C, settled for 4 hours, and the separated free water is sent to the purification system. Then, a composition containing water-soluble and oil-soluble de-emulsifiers, a diluent and salt water are simultaneously introduced into a pre-dehumidified high-viscosity emulsion, and the mixture is pumped through the process line for at least 10 minutes to create mass transfer processes before the dehydration stage. Vani. The process of settling of the emulsion is carried out in bullet-settling tanks at 80 ° C for 4 hours.

The combined use of water-soluble and oil-soluble demulsifiers allows to obtain a synergistic effect and, accordingly, reduce the residual water content in oil and reduce the consumption of demulsifiers. To confirm the occurrence of a synergistic effect, i.e. enhancement of the demulsifying ability of the mixture of water-soluble and oil-soluble demulsifiers, the surface tension at the oil-water interface was measured when each demulsifier was supplied autonomously, and then the mixture. Thus, the surface tension at the oil-water interface without a de-emulsifier is 39 mN / m, after treatment with a water-soluble demulsifier — 21 mN / m, an oil-soluble demulsifier — 19 mN / m, and a mixture of demulsifiers — 16 mN / m The demulsifier costs for surface tension measurements were 300 g / t.

To confirm the effectiveness of the proposed method, laboratory studies were carried out. To a sump model with natural bitumen emulsion

Mor-to-Carolian gas field with a water content of 60%, viscosity at 20 ° С 3500 mPa-s, density 989 kg / m3, containing 0.21% of mechanical impurities, after 5 heating and preliminary dehydration to a residual water content of 36 % injected composition according to the proposed method. Moreover, as a water-soluble demulsifier used

0 Separ-25 and oil-soluble - Diproxamine 157-65M, diluent - distillate, salt water - produced water with a density of 1120 kg / m. The resulting mixture was stirred for 10 minutes on a laboratory rocking chair and set aside for 4 hours in a water bath at 80 ° C. Then, after the discharge of water, its residual content was determined. The results of the experiments are shown in the table.

0 As can be seen from the table, positive results on the residual water content of up to 0.5% were obtained with a diluent consumption of 30-50%, an oil-soluble demulsifier 0.03-0.05%, a water-soluble demulsifier 0.02-0.03%, saline water 10-15%. A further increase in the costs of the components of the composition does not lead to improved results. With this accumulation of resistant intermediate layers

0 was not observed.

At a diluent consumption rate of less than 30%, oil-soluble demulsifier — 0.03%, water-soluble demulsifier — 0.02%, and salt water — 10% residual content

5 water in the dewatered oil is more than 0.5%.

The technical and economic effect of the proposed method is to reduce the residual water content in the oil. In prototype 2, the residual water content in the dehydrated bitumen is 1.05-1.12%, which is 2 times higher than the requirements of GOST 9956-65 (0.5). According to GOST, the discount for the quality of such marketable oil is 60 kopecks / ton. By

5, the proposed method has a water content in the crude oil of up to 0.5%, which excludes the said discount. With a plant capacity of 100,000 tons / year, the economic effect of introducing a new

0 ways is

E 60 kopecks, / t 100,000 tons / year 60000 rubles.

Claims (1)

Claim 5 A method for dewatering a highly viscous desalted oil emulsion by heating it, introducing an oil soluble demulsifier based on a block copolymer of ethylene oxide and propylene oxide, and a diluent, mixing and sludge, characterized in that, in order to reduce the residual water content in the oil, the water-soluble de-emulsifier based on the block copolymer of ethylene oxide and propylene oxides is additionally added to the salt in the following ratio components,% of the volume of the oil emulsion: a water-soluble demulsifier based on block copolymeramization of ethylene and propylene, 0.02-0.03; oil-soluble demulsifier based on block copolymer of ethylene oxide and propylene - 0.03-0.05; thinner - 30-50; salty water - 10-15. Salt Water Consumption 1 Note, 1 "Emulsion volume in all experiments 1 l 2 "Stirring time 10 min. 3" Time: 4 hours k. The temperature of the bed is 80 C. 5. The content of mechanical impurities in the dewatered oil is 0.05%. Table continuation