SU763450A1 - Method of oil dehydration and desalinization - Google Patents

Description

The invention relates to the field of the oil industry, in particular, to the processes of dehydration and desalting of oil in oil fields and refineries. There is a known method of preliminary separation of a gas-water mixture into gas, partially dehydrated oil and water. Oil from the well enters the separation zone, where the separation of the gaseous fluid occurs, the heavy fluid is directed to the emulsion treatment zone, where it is heated, the races. Slave Gs n water and clean oil, and is freed from gases and vapors. The closest to the invention in terms of its technological essence is a method of dehydration and desalted oil, including the treatment of a water-oil emulsion with a demulsifier in a droplet granulator, passing the emulsion through a layer of water in a settling unit, The fact is that the emulsion is divided into two streams at the exit from the depletor; one of which in an amount of 30-70% of the total emulsion volume from the upper zone of the depletor is passed through a layer of water, and in an amount of 30-70% is withdrawn from its bottom zone and is introduced into the oil sump area unit 2. The production capacity of a single settling tank with a volume of 200 m using this method is 3.7-4.0 million tons / year for finished oil. The known method is effective and allows to increase the productivity and quality of the prepared oil. However, when the emulsion is introduced into the settling tank by two streams only in the oil and water zones, there is an intermediate layer in it, as in conventional devices, in which small drops of water less than 20 microns in size and particles of mechanical impurities accumulate. As they accumulate, the thickness of the intermediate layer increases, making it difficult for the precipitated water droplets to reach the oil-water interface, and therefore the quality of oil at the outlet from the aggarat is periodically deteriorated, which ultimately leads to a periodic decrease in plant performance. The aim of the invention is to increase the productivity of the process. The goal is achieved by the described method of oil dehydration and desalting, which includes treating a water-oil emulsion with a deemulant in a droplet blender followed by injecting oil from a droplet locking body into a settling tank in three streams, while the oil phase from the upper zone of the hoe sweep is 20-30% of the total the volume of oil is fed under the surface of the separation section of the settling tank; an intermediate phase of the middle zone kapleukrupnitel in the oil layer settler. The proposed method makes it possible to further intensify the process of dehydration and desalting of oil due to the fact that a smaller part of the nave is subjected to washing through a layer of water; These are only with the smallest drops of water, and the lower layer of the stream in the dropper, containing mostly water, does useful work on breaking the intermediate layer of the phases and trapping the small droplets of formation water dispersed in the oil when it moves towards the intermediate layer of water phases. This effect is exacerbated by large drops of water precipitating from the oil zone, separated from the oil withdrawn from the middle part of the droplet consolidator. The drawing shows a schematic diagram of the implementation of the method, the method. Example 1. A water-in-oil emulsion treated with drainage water in an amount of 6.0 after a preliminary discharge from it of the main volume of produced water in reservoirs of a commercial fleet with a residual water content of 3% is sent to an oil preparation unit. An emulsion with a water droplet size of not more than 20 µm in heat exchanging equipment is heated to 30-45 ° C. Before heating, a reagent, a demulsifier, is calculated at a rate of 20-30 g / t of oil. The heated emulsion is introduced into a dropper 1, where, due to hydrodynamic effects, they destroy the reservation shells on the globules of the formation water and enlarge them to sizes of 40-1500 microns. At the end portion of the dropleper breaker 1, the entire emulsion volume is divided into three structural parts using horizontal baffles 2: upper stream I, characterized by containing 40–200 µm fine water droplets, lower stream II, characterized by predominantly free water and 1P average stream, characterized by the content of large water droplets with sizes 200-1500 microns. Oil from the upper zone I of the drip pan in the amount of 30% of the total emulsion volume is introduced into the water zone of the sump 3 under the interface surface of the oil-water. When the oil rises through the water layer, small drops of water after exiting the horizontal switchgear 4 are transferred into the volume of free drainage water (the oil is being washed). The jet of oil with the remaining small drops of water, rising up, passes through the interface. The kinetic energy of the oil jets disturbs the intermediate layer and sets in motion the small droplets of water suspended in this layer, which coalesce and grow to a size that ensures their sedimentation to the bottom of the sump. At the same time, the flow of the GI from the middle zone of the drop separator 1 in the amount of 40% of the total emulsion volume is introduced into the oil zone of the settling tank .3 through the front distributor 5. On the path of the emulsion to the outlet nozzle 6, water droplets are separated from the oil and deposited on the bottom a sump in which they, in addition, meet, capture small drops of water from rising oil and the intermediate layer. Oil, containing predominantly free water, in an amount up to 30% of the total emulsion volume from the lower zone. And the breaker 1 is jetted through a horizontal distribution device 7 into the intermediate layer of phases. Water jets, exit from the device 7 in the direction of the interface section, also vigorously disturb the intermediate layer and trap small drops of water from the layer and rising towards the oil. The dehydrated and desalted oil with a water content of 0.1-0.2% and salts 40 mg / l is removed from the settling apparatus through the pipe 6, and the water separated from the oil is drained through the pipe Example 2. A water-oil emulsion treated with drainage water in the amount 600 after the preliminary discharge from it of the main volume of reservoir water in the tanks of the commodity park with a residual water content of 15% is sent to the oil treatment installation. The emulsion containing. droplets of one size of not more than 20 microns in the heat exchange apparatus are heated to 30-45 ° C. Before heating, a demulsifier reagent is injected into the emulsion at the rate of 20-30 g / t of oil. The heated emulsion is injected into a droplet splice 1, where, due to hydrodynamic effects, the armor shells on globular plastic water are destroyed and enlarged to sizes of 601500 microns. At the end of the droplet breaker 1, the entire volume of the emulsion is divided into three structural parts using horizontal partitions 2: upper stream I, characterized by a fine water content of 60-200 µm, lower stream I, characterized by a content of predominantly free water and average flux Ø, characterized by the content large drops of water with sizes 200-1500 microns. Oil from the upper zone I of the drople disperser 1 in the amount of 20% of the total emulsion volume is introduced into the water zone of the sump 3 under the oil-water interface. With a higher content of formation water (15%) in the emulsion, oil with small drops of water takes up a smaller volume of droplet grappler compared to a low water content in the emulsion (3%). When emulsion jets rise through a layer of water, small drops of water after exiting the horizontal distribution the device 4 is transferred to the volume of drainage water (the oil is being washed). The jet of oil with the remaining small drops of water, rising up, passes through the interface. The kinetic energy of the oil jets causes a disturbance in the intermediate layer and the small droplets of water suspended in this layer are put into motion, which merge and grow to a size that ensures their sedimentation to the bottom of the settler.

At the same time, the lii stream from the middle zone of the drop separator 1 in the amount of 40% of the total emulsion volume is introduced into the oil zone of the settler 3 through the front distributor 5. On the path of the emulsion to the outlet nozzle 6, water droplets are separated from the oil and deposited on the bottom of the settler in which they additionally meet, capture small drops of water from rising oil # of intermediate layer.

Oil, containing mostly free water, in the amount of 40% of the total emulsion volume from the lower zone. And the fragmenter 1 is jetted through a horizontal distributor 7 into the intermediate

layer of phases. The water jets, the exit from the introductory device 7 in the direction of the interface, also vigorously disturb the intermediate layer and capture small drops of water from this layer and rising towards the oil.

The dehydrated and desalted oil with a water content of 0.0-0.2% and salts of 40 mg / l is removed from the settling apparatus through the nozzle b, and the separated

0 from oil water is taken through the pipe, 8, -. The application of the proposed method of dehydration and desalting of oil due to the separate simultaneous

5 injecting oil with small drops of water under the interface and in the bulk phase of the emulsion into the intermediate layer with oppositely directed jets, and oil with scaled drops of water

0 into the oil zone of the settling unit allows to intensify the sludge oil process and increase the sump capacity from 500 m / h to 600.

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Claims (1)

Invention Formula A method of dewatering and desalting oil, which involves treating a water-oil emulsion with a demulsifier in a droplet grader, followed by a separate supply of the oil and water phases from the drier refiner to the settling tank, in order to increase the productivity of the process, the oil from the droplet fragmenter is fed into the sump by three streams. In this case, the oil phase from the upper zone of the drop separator, to the extent of 20-30% of the total volume of oil, is fed under the interface of the septic tank, the aqueous phase in the amount of 30-40% of the total volume of oil and from the lower zone the drip grinder is fed to the intermediate layer in the settling tank with feeding of the remaining part of the intermediate phase From the middle zone of the drip hood to the oil layer of the settler, Information sources, taken into account in examination 1, US Patent 2,933,447, Cl, 252-330, 1960 ....  2, USSR Author's Certificate of Application No. 2530368/04, class C, C 10 G 33/06, 1977 (prototype).