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Horizontal settling tanks OG


Petroleum settling tank OG are designed to remove formation water, mechanical impurities and salt from oil. They areused at oil production and processing enterprises and preliminary water and oil processing terminals.

Petroleum settling tank OG design

This type of settling tank has horizontal shape with elliptical bottoms. Insude there are placed devices that allow you to retain mechanical particles and condensed moisture. The latter is then removed and used for technological purposes.

Horizontal settling taks produced at SARRZSARRZ produces horizontal settling tanks with a volume of from 25 up to 200 m3. The tanks are delivered to the operational location in maximum factory readiness as the body is all-welded with tank hatches and fitting pipes at the top and supports at the bottom.

The settling tanks are mounted aboveground: the are supports at the lower shell to settle the tank onto the reinforced concrete foundation.

Stairs and service platforms may be provided for personnel access to the fittings.

Structural design of the settling tanks OG are carried out on the basis of the Data sheet or technical requirements for production. The volume depends on the desired capacity. The steel grade depends on the crude-oil emulsion composition. We produce settling tanks of 16GS os 09G2S with a thickness of up to 16 mm. Inner surface is treated with special anticorrosion primers. Optionally the tanks may be heat-treated. The outer surface is also covered with primer and enamel. If needed, the heat insulating may be applied on the outer side that will prevent crude-oil emulsion from freeze and thickening.

Settling tanks specifications

Criteria Value
Volume, m3 25-200
Capacity, m3/day 2000-15000
Operating medium crude-oil emulsion
Oparating pressure, MPa 1.0; 1.6; 2.5
Operating medium temperature, ºС -60...+100
Climatic category N, NF
Operating temperature, ºС -40...+60 depanding on the material design
Material 09G2S, 16GS
Seismicity, points up to 9
Service life, years not less than 20

Internal arrangement of the settling tanks OG

There is formation water inside the sump. The oil-water emulsion enters through the inlet pipe. The holed plates and box-shaped distributers are located in the lower part. While passing through them, the emulsion is separated into water and oil due to their density margin. As the oil density is less, it goes up to the upper part. The treated oil goes to the oil gathering line and is discharged. Separated water joins with formation water and is gravitated to the bottom and then discharged to the formation water treatment unit.

The emulsion also contains gas particles which are gathered in the special collector and then are also discharged.

Each settling tank OG is equipped with a set of measuring and shut-off devices: an interfacial level gauge, a regulator valve, a sampler, a pressure gauge, and a safety valve. The exact composition of the equipment is selected at the design stage.

Typical drawing of the settling tank OG

Settling tank OG drawing

Typical overall dimensions

Volume, m3 Inside diameter L B H Sk S д l1 l2 l3 l4 l5 l6 l7 l8 l9 l10 h1 h2
50 2400 12900 2520 3215 10 12 5500 - 1150 1550 2500 5500 - 800 500 930 490 300
100 3000 14000 3040 3920 14 16 2940 5780 680 900 1830 3065 265 680 400 1050 500 400
200 3400 22000 3432 4320 16 20 4925 9650 875 1100 4000 4700 4750 1000 500 1450 700 600

Nozzle schedule

Designation Assignment, DN, mm OG-50P OG-100P OG-200P
DN, mm pcs DN, mm pcs DN, mm pcs
Ф1, А2 crude-oil emulsion inlet 350 2 500 2 700 2
Б gas outlet 300 1 80/500 1 80/500 1
В1, В2 oil outlet 200 1 300 2 300 2
Г formation water outlet 200 1 300 1 300 1
Д drainage 200 1 300 1 300 1
Е safety valve 200 1 200 1 200 1
Ж level control 300 1 300 1 300 1
З1, З2 cleaning 200 1 150 2 150 2
К level control 200 1 10 1 10 1
Л1, Л2 level control 50 2 50 2 50 2
М1, М2, М3 sampling connection 15 5 15 3 15 3
Н1, Н2 differential pressure gauge 15 2 15 1 15 1
П pressure gauge connection 15 1 15 1 15 1
Р hatch 500 1 600 1 800 1
С manhole 500 1 500 1 500 1
И drainage 150 1 150 1 150 1

How to buy settling tank at SARRZ?

In order to know the price, you may:

  • call at 8-800-555-9480
  • email
  • fill in the Data sheet and send it at e-mail

We perform a full range of services: design development, volume calculation depending on the required performance, the selection of the steel grade and method of anticorrosive treatment, oilfield equipment manufacturing, shipping separation units, installation of settling tanks and vessels and their commissioning.


See also:

Oil gas separatorsCentrifugal separatorsThree-phase separators TFS-L
Three-phase separators TFS-GOil dehydration vessels BONOil degassing buffer BDN
Water treating vessels OVNAdvanced water filtration vessels UOVWater degassing buffer BDV
Flotators-degasifiers FDMeshed gas separators GSGas separators
Flare knockout drumsFlare unitsSettling tanks OG
Oil-settling tanks ONSettling tanks with baffle plate OGN PWater settling tanks OW
Water settling tanks with liquid filterHydrophobic water settling tanks