Rice. 8.1.Sump OG-200S

The following designations are accepted in the cipher: OG - horizontal sump; the first digit is the capacity of the container ( m 3); C - with a separation compartment. Settlers are made of steel grades 09G2S-6 for operation at temperatures from minus 40 about C up to plus 200 about C(version -1) and from steel 09G2S-8 for operation at temperatures from minus 60 O C to plus 200 about C.

Settler OG-200S(Fig. 8.1) represents a steel horizontal cylindrical container with a diameter of 3400 mm with elliptical bottoms. With the help of a partition 3, the container is divided into two compartments, of which the left 1 is separation, and the right 11 is settling.

The left and right compartments communicate with each other using two distributors, which are steel pipes 8 with an outer diameter of 426 mm with holes at the top. Above the holes of the distributors are box-shaped emulsion distributors 7, which have holes on their side faces.

In the upper part of the separation compartment there is a gas separator 2 connected to the gas outlet fitting 10 located in the left bottom.

In the upper part of the right compartment, there are four oil collectors 4 connected to a collector and a fitting for the outlet of settled oil. In the lower part of this compartment there is a fitting 6 for removing separated water.

The heated oil emulsion enters the distributor located in the upper part of the separation compartment through nozzle 1 1 . At the same time, part of the gas is released from the flooded oil, which is in it both in the free and in the dissolved state. The separated gas is discharged through the fitting 10 into the collection network. The liquid level in the separation compartment is regulated by an interfacial level regulator, the float mechanism of which cuts into the hatch 9. Degassed oil from the separation compartment enters two collectors 8 located in the settling compartment 11.

From the collectors, oil enters under the box distributors and through the holes drilled in their side surfaces, is directed in thin streams under the level of formation water in the compartment. Due to the presence of box distributors, oil acquires vertical movement over a large area of ​​the unit. Dehydrated oil floats up and enters collectors 4, located in the upper part of the settling compartment, and is removed from the apparatus through fitting 5. Formation water separated from oil enters the right side of the settling tank and is discharged through nozzle 6 with the help of a float regulator of the interfacial level into the production water treatment system.

Rice. 8.2. Schematic diagrams of various types of settling apparatus: a - with a perforated grate; b - with a lower distributed input under the drainage water layer and an upper distributed oil outlet; c - with a sectional droplet maker, a lower distributed emulsion inlet and an upper distributed oil outlet; d - vertical with a sectional droplet generator and a lower distributed emulsion inlet under a layer of drainage water; e - with end distribution devices for emulsin input and oil removal; f - with an overflow partition and oil flushing in the drainage water layer

The settling tank OG-200S is supplied complete with control and measuring devices that allow automatic regulation of the levels of the "oil-gas" and "oil-formation water" sections in the compartments, as well as local control over the pressure of the medium in the device, the levels of the "oil-gas" section and "oil-reservoir water".

Settlers are used to settle oil emulsions after heating them in block or stationary furnaces. Settling tanks with bottom distributed emulsion inlet (OG-200, OG-200S, OVD-200) and settling tanks with radial and horizontal raw material inlet (OBN) are the most widely used.

The horizontal settling tank OG-200S (OG-200) is designed for settling oil emulsions in order to separate the latter into their constituent oil and formation water. It is allowed to use the unit for the preparation of light and medium oils that do not contain hydrogen sulfide and other corrosive components. The following designations are accepted in the cipher: OG - horizontal sump; number - the volume of the container (in m 3); C - with a separation compartment.

The settling tank OG-200S (Fig. 67) is a horizontal steel cylindrical tank with a diameter of 3400 mm with elliptical bottoms.

Rice. 67. Scheme of the OG-2000S sump

septum 3 the container is divided into two compartments, of which the left I is a separation compartment, and the right II is a settling compartment. The compartments communicate with each other using two distributors, which are steel pipes. 8 with an outer diameter of 426 mm, equipped with holes located in the upper part. Box-shaped emulsion distributors are located above the distributor holes. 7 having holes on their side faces.

At the top of the separation compartment is a gas separator 2 , connected by means of a flange elbow to the gas outlet fitting 11 located on the bottom left. In the upper part of the settling compartment there are four oil collectors 4 , connected to the collector and the fitting of the outlet of settled oil. In the lower part of this compartment there is a fitting 6 for removing separated water.

Heated oil emulsion through choke 1 enters the distributor located in the upper part of the separation compartment. At the same time, part of the gas that is in it both in the free and in the dissolved state is released from the flooded oil. The separated gas through the fitting 11 dumped into the network. The liquid level in the separation compartment is regulated by an interfacial level regulator, the float mechanism of which cuts into the hatch 9 . Degassed oil from the separation compartment enters two collectors 8 located in the settling compartment. Above the collectors are emulsion distributors 7 . From the collectors, oil enters under the box distributors and through holes drilled in their side surfaces flows out in thin streams under the formation water level in the compartment. Due to the presence of box-shaped distributors, oil acquires vertical movement over a significant area of ​​the apparatus. Dehydrated oil floats up and enters the collection 4 located in the upper part of the settling compartment, and through the fitting 5 is removed from the device. Formation water separated from oil enters the right side of the settling tank and through the choke 6 with the help of a float regulator of the interfacial level, it is discharged into the industrial wastewater treatment system.

The settling tank OG-200S is supplied complete with control and measuring devices that allow automatic regulation of the levels of the "oil - gas" and "oil - formation water" sections in the compartments, as well as local control over the pressure of the medium in the apparatus, the levels of the "oil - gas" section and "oil - formation water". The technical characteristics of the OG-200S sump are given below.

Marketable oil throughput, t/day 40008000

Operating medium oil, gas, produced water

Working pressure, MPa 0.6

Medium temperature, °С up to 100

Apparatus volume, m 3 200

Dimensions, mm:

Length 25420

Width 6660

Height 5780

Weight, kg 48105

Horizontal settling tanks OVD-200 and OBN-3000/6 are designed for settling oil emulsions in order to separate the latter into their constituent oil and produced water. The following designations are accepted in the cipher: ATS - a sump with vertical movement; 200 - tank volume (in m 3); OBN - block oil sump; the number in the numerator is the nominal throughput (in m 3 / day); the number in the denominator is the working pressure.

The settling tank OVD-200 (Fig. 68) is a horizontal steel cylindrical tank with a diameter of 3400 mm.

Rice. 68. General view of the OVD-200 sump

The sump is equipped with an emulsion distributor 2 , oil collectors 1 and water 4 made of perforated pipes. The emulsion distributor consists of two combs (double-sided) with four pipes in a row. Holes are located along the lower generatrix of the distributor pipes, under which U-shaped fenders are installed 3 . This arrangement of holes prevents the accumulation of dirt and mechanical impurities in the pipes and contributes to the uniform removal of emerging water. Fenders are designed to dampen the kinetic energy of the flowing emulsion jets, distribute them evenly over the section of the apparatus and prevent mixing of the underlying water layers.

The operation principle of the settling tank is based on gravity settling and on the effect of emulsion flushing, both in the drainage water layer and in the intermediate layer of highly concentrated emulsion, which acts as a kind of coalescing filter. The technical characteristics of the OVD-200 settling tank are given below.

Raw material throughput, m 3 / day 4000-8000

Working medium oil (petroleum), water

Working pressure, MPa 0.6

Medium temperature, °С up to 100

Oil water cut, %:

At the entrance up to 30

Outlet 0.20.5

Viscosity of the emulsion, no more than, mm 2 / s 10

Apparatus volume, m 3 200

Weight, kg 34950

The settling tank OBN-3000/6 (Fig. 69) is also a horizontal steel cylindrical tank with a diameter of 3400 mm. It is equipped with an emulsion dispenser 3 , oil collectors 1 and water 5 , as well as the corresponding fittings for introducing the emulsion 4 , oil output 2 and water 6 . A feature of the sump is the use of an emulsion distributor and an oil collector in the form of perforated drums located respectively along and across the axis of the cylindrical container. The principle of operation of the sump is based on gravitational settling with relatively horizontal movement and separation of the emulsion into oil and water.

Rice. 69. General view of the settling tank OBN-3000/6

The technical characteristics of the settling tank OBN-3000/6 are given below.

Apparatus volume, m 3 200

Weight, kg 34 000

Working medium oil, produced water

Throughput, m 3 /day 30006000

Water cut of raw materials, no more than, % 30

The water cut of the outgoing oil is not more than,% 0.5

Electric dehydrators are designed for deep dehydration and desalting of oil.

Rice. 70. Electric dehydrator EG-200-10

The following designations are accepted in the cipher: EG - electric dehydrator; the first number is the volume of the container in m 3, the second is the working pressure.

The electric dehydrator is a horizontal steel cylindrical container with a diameter of 3400 mm. Equipped with an emulsion distributor, oil and water collectors made of perforated pipes.

These devices of the electric dehydrator are no different from the corresponding devices in settling tanks of the OBD-200 type. Unlike settling tanks, the EG-200-10 electric dehydrator is equipped with two electrodes - upper and lower, where high voltage of industrial frequency is supplied. The principle of operation of the electric dehydrator is based on the impact on the emulsion of an electric field of variable frequency. Under the influence of electric field forces, water globules in an emulsion experience continuous deformation, which contributes to the effective destruction of emulsions. The technical characteristics of electrohydrators are given in Table. 27.

Table 27

Indicators	Electric dehydrators
	1EG-160	2EG-160	EG-200-10
Marketable oil throughput, t/day	2000-8000	3000-9300	5000-11500
Working temperature, С	up to 110	up to 110	up to 110
Power of electric transformers, kVA	50	50	150
Voltage between electrodes, kV	up to 44	up to 44	up to 50
Tank capacity, m 3	160	160	200

5.6. Chemical dosing units

At present, the domestic industry manufactures units and dosing units for chemical reagents (demulsifiers, corrosion inhibitors, scaling, etc.) BR-2.5; BR-10; BR-25; NDU; UDS; UDE; UDPV. Designed for the preparation and dosed injection of liquid demulsifiers and corrosion inhibitors at any point in the pipeline of the field system for transporting and treating oil at the well site before the complex oil treatment unit.

All equipment of the BR-2.5 and BR-10 installations (Fig. 71) is placed in a heat-insulated booth 1 mounted on a welded frame-sleigh 2 . The booth is divided by a hermetic partition 4 into two compartments (technological and instrumental).

Technological capacity is placed in the technological compartment 8 , tubular electric heater 5 , gear 7 and dosing 6 pumps, as well as monitoring and control equipment 3 .

By supplying water and a concentrated reagent in certain proportions to the mixer at the BR-25 unit, if necessary, it is possible to prepare and dose an aqueous solution of reagents.

Rice. 71. Dosing units for chemicals BR-2.5 and BR-10

Technological characteristics of BR blocks are given in Table 28.

Table 28

Indicators	Chemical Dosing Unit
	BR-2.5	BR-10	BR-25
Dose size, g/t	1050	1050	1050
Dosing medium viscosity, MPas	up to 1000	up to 850	up to 850
Dosing pump flow, l/h	2,5	10	25
Recommended discharge pressure, MPa	10	10	4
Dosed reagent temperature, С	5060	2060	2060
Temperature environment, С	-40+50	-40+50	-40+50
Stock of chemical reagent, days	15	30	210
Overall dimensions, mm	33602300 2725300	377022503090	37702400 26804500
Weight, kg	3000	3090	4500

5.7. Oil tanks

Oil reservoirs (tanks) are designed for accumulation, short-term storage and accounting of "crude" and turning oil. A group of tanks concentrated in one place is called a tank farm.

According to SNiP, the volume of raw material reservoirs must be at least five times the daily volume of oil production, and commodity reservoirs - two times. In the fields, mainly steel cylindrical tanks with a capacity of 10020,000 m 3 and less often reinforced concrete underground tanks with a capacity of up to 100,000 m 3 are used.

Oil tanks are built from non-combustible materials in ground, semi-underground and underground versions.

Steel tanks are constructed with a constant or variable wall thickness of the shell. Depending on the volume and height of the tank, they are made of sheet steel with a thickness of 4 to 10 mm. Due to technological conditions (welding), sheet steel with a thickness of less than 4 mm cannot be used, even if the calculated wall thickness is less.

When constructing the tank shell, steel belts can be arranged in three ways: stepped, telescopic and end-to-end.

The walls of vertical cylindrical tanks in the absence of excess pressure above the liquid surface experience a pressure that depends on the height of the liquid level column to the tank zone under consideration. For example, at depth h walls are under pressure R equal to:

.

The wall thickness is determined from the equation:

,

h- tank height, mm;  - liquid density, kg/m 3 ; g- acceleration of gravity, m/s 2 ; D- tank diameter;  add - allowable tensile stress.

The thickness of the sheet steel of the bottoms of the tanks is not calculated and is usually taken no more than 5 mm, since the hydrostatic pressure is perceived by the foundation.

Tank covers are made of sheet steel with a thickness of not more than 2.5 mm and are: conical, spherical, flat.

In oil fields, tanks with flat lids are most often used.

The roofs of the tanks are located on building floors (trusses), which can be supported both on intermediate columns inside the tank and directly on its walls.

The equipment of steel tanks and their design schemes must ensure their correct and safe operation, in particular: 1) accumulation and emptying of tanks; 2) oil level measurement; 3) oil sampling; 4) cleaning and repair of tanks; 5) oil sedimentation and removal of produced water; 6) maintaining the pressure in the tank within safe limits.

The equipment shown in Fig. 1 is mounted on oil tanks. 72.

Rice. 72. Layout of equipment on a steel tank:

1 - receiving and distributing branch pipes; 2 - flap for forced closing; 3 - intake pipe; 4 - measuring hatch; 5 – skylight; 6 - manhole; 7 - siphon; 8 - breathing valve; 9 hydraulic relief valve

The diameters of the intake and distribution pipes are determined by the specified capacity of the pumped oil and vary within 150700 mm. The speed of fluid movement in them is within 0.52.5 m/s, depending on the viscosity of the oil.

clapping 2 installed to prevent oil leaks from tanks in case of malfunction of valves.

riser pipe 3 is mounted inside the tank and is designed to take oil from the required height.

Measuring hatch 4 serves to measure the level of oil and produced water in the tank, as well as to take samples with a sampler.

The gauge hatch is mounted on a branch pipe welded vertically into the roof of the tank. The metering hatch cover is hermetically sealed by means of a gasket and a pressure, hinged bolt. Inside the measuring hatch there is a guide block, along which a measuring tape with a lot is lowered into the tank.

The block is made of copper or aluminum to prevent sparking.

Skylight 5 - for penetration of light and airing before cleaning, repair. A manhole for people to enter, during repairs, cleaning, as well as lighting and ventilation. The siphon-type water outlet is intended for the selection of formation water.

Siphon elbow height h c is determined by calculation depending on the selected ratio of the heights of the water columns h in and oil h n in the tank according to the formula:

where
.

Breathing valve 8 automatically reports the gas space of the tank with atmosphere at the moment when the maximum allowable pressure or vacuum is created in the tank as a result of temperature changes, as well as when filling and emptying the tank. Breathing valves are designed for overpressure and vacuum in the gas space of the tank R g = 20 mm w.c. Art. With such excess pressure, the mass of the tank roof, made of 2.5 mm thick sheet steel, is balanced by the force of excess pressure on it. The mass of 1 m 2 of the roof is 20 kg and, therefore, the roof will not experience stress if the pressure from the inside does not exceed the pressure created by the mass of the roof (Fig. 73).

When pressure rises from inside the tank, the valve 2 rises and discharges excess gas into the atmosphere, and when the pressure inside the tank decreases, the valve opens 1 and air enters the reservoir.

The valve body and seat are made of aluminum alloy to avoid corrosion. The size of the breathing valves is chosen depending on their allowable throughput.

Rice. 73. Functional diagram of the breathing valve:

1 – vacuum valve; 2 – pressure valve; 3 – flange for installing the valve on the fire fuse

The breather valve is a critical element of the tank equipment, and therefore, special attention should be paid to the good condition of the valves and their correct operation. In winter, breathing valves often fail, because when wet oil vapor passes through the valve, moisture, condensing on the plates and seats, leads to their mutual freezing. This drawback is eliminated by isolating the freezing surfaces of the valve with fluoroplastic, which has a high mechanical strength at low temperatures and high chemical resistance.

Hydraulic Relief Valve 9 is designed to limit excess pressure or vacuum in the gas space of the tank in case of failure of the breathing valve, as well as in case of insufficient cross-section of the breathing valve to quickly pass gas or air. Safety valves are designed for a slightly higher pressure and vacuum than the breathing valve: for an overpressure of 60 mm of water. Art. and discharge 40 mm water. Art. Its functional diagram is shown in fig. 75.

Rice. 74. Functional diagram of the hydraulic safety valve

The safety valve is filled with non-freezing, non-evaporating and low-viscosity liquids - a solution of glycerin, ethylene glycol, etc., forming a hydraulic seal through which an excess gas-air mixture is bubbling from the tank or "breathing" into the tank.

In cases of a sharp increase in pressure in the tank, liquid may be ejected from the valve into the annular channel, and the liquid flows back from it through the holes in the pocket wall. Fire fuses are installed on the tanks complete with breathing and safety valves and are designed to protect the gas space of the tank from the penetration of flame into it through the breathing valve.

The principle of operation of fire fuses is that the flame, getting into the fire fuse, passes through a system of small-section valves, as a result of which it is crushed into separate small streams; the contact surface of the flame with the fuse increases, the heat transfer to the walls of the channels increases, and the flame dies out.

The main part of fire fuses is a cylindrical spiral tape cassette made of non-ferrous metals and placed in the fuse case.

Tanks steel vertical cylindrical (fig. 75) are intended for storage of oil, oil products with a pontoon and without a pontoon.

Rice. 75. Steel vertical tank Manufacturer: Novokuznetsk plant of tank metal structures.\Table 29

Steel vertical tanks

Denomination volume, m3	Geometer. characteristics, mm		Reference total weight, t
	Diameter	Height	Without pontoon	with pontoon
Design temperature -40С and higher
100	4730	5960	8,2	10,3
Design temperature -40С to -65С
100	4730	5960	8,4

LITERATURE

1. Bukhalenko E.I. etc. Technique and technology of flushing wells.- M.: Nedra, 1982.- 197 p.

2. Molchanov A.G., Chicherov L.G. Oilfield machines and mechanisms.- M.: Nedra, 1976.- 328 p.

3. Handbook of the master of oil production. Baku.- Aznefteizdat, 1952.- 424 p.

4. Akulyshin A.N. and others. Exploitation of oil and gas wells.- M.: Nedra, 1889. 480 p.

5. Equipment and tools for the repair of oil wells. Krets V.G., Shmurygin V.A. and others - Tomsk: Ed. TPU, 1996. 72 p.

6. Ishmurzin A. A. Machines and equipment for oil, gas and water collection and treatment systems. - Ufa: Izd. Ufimsk. Oil in-ta, 1981.- 90 p.

7. Oilfield equipment. Set of Catalogs. Krets V.G., Koltsov V.A., Lukyanov V.G., Saruev L.A. and others - Tomsk: Ed. TPU, 1997.-822 P.

8. Krets V.G. Development and operation of oil and gas fields. Uch. allowance Tomsk: Ed. TPU, 1992.- 112 p.

ANNEX 1

Rice. 77. Unified technological scheme of the complex for the collection and treatment of oil, gas and water in the oil-producing region:

1 - well; 2 – automated group metering unit; 3 – demulsifier supply unit; 4 – separator  steps; 5 – sump for preliminary water discharge; 6 – furnace for heating the emulsion; 7 - drop former; 8 – deep dehydration sump and  separation stages; 9 – fresh water inlet mixer; 10 – electric dehydrator for desalination; 11 separator  (hot) separation stage; 12 – commercial oil reservoir; 13 ; 16 ; 19 - pump; 14 - an automatic machine for measuring the quantity and determining the quality of commercial oil; 15 – reservoir of substandard oil; 17 – water purification unit; 18 - purified water tank; 20 – water degasser unit with a pump; 21 – unit for measuring water flow; 22 – unit for receiving and pumping out captured oil; 23 – capacity-sludge accumulator; 24 - unit for receiving and pumping wastewater; 25 multihydrocyclone for separating mechanical impurities from stagnant (rain) water;

 - commercial petroleum gas;  - commercial oil;  - purified water at the sewage pumping station; V – fresh water; V commercial storm drains; V - gas per candle.

Knots - installations: GZU - measurement of production of wells;

UPG - gas treatment;

UPN - oil treatment;

UPV - water treatment;

UPSh - preparation of sludge or mechanical impurities.

Exhaust gas oil settlers- special equipment designed for the separation of water-oil emulsions. In the process of separation, oil is obtained, which is then collected, and formation water, which is discharged. Together with formation waters, mechanical impurities and salts are removed from the raw material. Some designs of oil settlers also allow the removal of dissolved gas.

Scope of EG oil settlers

Exhaust gas oil settlers are indispensable for deep oil cleaning, therefore they are actively used in oil fields during the extraction and preparation of oil and at oil refineries.

Principle of operation of exhaust gas oil settlers

In oil settlers of the OG type, the separation of oil and water occurs due to the difference in their specific gravity. The water-oil emulsion enters through the inlet fitting into two perforated collectors located in the lower part of the sump. The water-oil emulsion emerging through the holes in thin streams enters under the formation water layer. The water droplets contained in the emulsion come into contact with the formation water present in the apparatus, coarsen and settle down. Oil with a lower specific gravity floats up. Also, part of the gas that is in it both in the free and in the dissolved state is released from the flooded oil. The separated gas is discharged through the fitting into the collection network. The dehydrated oil accumulated in the upper part of the sump enters the oil collector and is discharged from the apparatus through a fitting. Formation water separated from oil is discharged through an overflow device into the field wastewater treatment system. To determine the phase separation level, the sump is equipped with a level gauge. The interfacial level in the oil sump is maintained using a control valve by changing the amount of discharged water. To take liquid samples from different levels, the sump is equipped with a rotary sampler. Like any pressure vessel, the sump is equipped with shut-off valves, pressure gauges for measuring overpressure and spring-loaded safety valves to protect against unacceptable overpressure.

Main technical characteristics of oil sedimentation tanks:

An example of a symbol for an exhaust gas sump

Oil sump - OG, nominal volume - 200 m 3.

Conditions for the use of exhaust gas oil settlers

• The working medium is oil, formation water.
• Hazard class of working environments 3, 4 according to GOST 12.1.007.
• Climatic version: U1 and HL1 according to GOST 15150 with air temperature during operation from minus 40ºС to plus 40ºС from minus 60ºС to plus 40ºС.
• Exhaust gas sedimentation tanks designed for a working environment containing hydrogen sulfide are equipped with internal devices and filling made of 08X18H10T stainless steel.
• Possibility of operation in geographic areas with seismicity up to 8 points inclusive on a twelve-point scale. The use of equipment in regions with a seismic activity of more than 8 points is possible after a preliminary calculation, taking into account specific sizes.
• Mean time between failures is not less than 17,000 hours.
• Average service life before overhaul is at least 70,000 hours.
• Service life not less than 20 years.

To settle oil emulsions after heating them in block or stationary furnaces, oil sedimentation tanks. Designed for settling oil emulsions in order to separate the latter into their constituent oil and produced water. It is allowed to use the unit for the preparation of light and medium oils that do not contain hydrogen sulfide and other corrosive components.

Types and marking of oil sedimentation tanks

Settling tanks with a bottom distributed emulsion inlet of types OG, OH and OVD, as well as settling tanks with radial and horizontal input of raw materials OBN, are most widely used.
The type of apparatus is reflected in its marking; For example:

• OG-200S - horizontal sump; number - tank volume (in m3); C - with a separation compartment.

• OVD-200 - sump with vertical movement; 200 - tank volume (in m3);

• OBN-3000/6 - block oil sump; the number in the numerator is the nominal capacity (in m3/day); the number in the denominator is the working pressure.

• OH-1.6-2400-2-T-I - oil sump; 1.6 - conditional design pressure (MPa); 2400 - inner diameter (mm); 2 - material design (below -40ºС); T - the presence of heat treatment; And - the presence of fasteners for thermal insulation.

Arrangement and principle of operation of settling tanks OG-2000S, OVD-200 and OBN-3000/6

Consider the device and principle of operation of sedimentation tanks using the example of their three most common types.

Oil settler OG-200

Settler OG-200 C is a horizontal steel cylindrical tank with a diameter of 3400 mm with elliptical bottoms.

Scheme of the oil sump OG-2000S

The partition 3 divides the container into two compartments, of which the left I is a separation compartment, and the right II is a settling one. The compartments communicate with each other using two distributors, which are steel pipes 8 with an outer diameter of 426 mm, equipped with holes located in the upper part. Above the holes of the distributors are box-shaped emulsion distributors 7, which have holes on their side faces.

In the upper part of the separation compartment there is a gas separator 2, connected by means of a flange elbow to the gas outlet nipple 11, located in the left bottom. In the upper part of the settling compartment, there are four oil collectors 4 connected to a collector and a fitting for the outlet of settled oil. In the lower part of this compartment there is a fitting 6 for removing separated water.

Heated oil emulsion through fitting 1 enters the distributor located in the upper part of the separation compartment. At the same time, part of the gas that is in it both in the free and in the dissolved state is released from the flooded oil. The separated gas is discharged through the fitting 11 into the collection network. The liquid level in the separation compartment is regulated by an interfacial level regulator, the float mechanism of which cuts into the hatch 9. Degassed oil from the separation compartment enters two collectors 8 located in the settling compartment. There are emulsion distributors 7 above the collectors. From the collectors, oil enters under the box-shaped distributors and through holes drilled in their side surfaces flows out in thin streams under the formation water level in the compartment. Due to the presence of box-shaped distributors, oil acquires vertical movement over a significant area of ​​the apparatus. The dehydrated oil floats up and enters the collector 4, located in the upper part of the settling compartment, and is removed from the apparatus through the fitting 5. Formation water separated from oil enters the right side of the settling tank and is discharged through nozzle 6 with the help of a float regulator of the interfacial level into the industrial wastewater treatment system.

The settling tank OG-200S is supplied complete with control and measuring devices that allow automatic regulation of the levels of the "oil - gas" and "oil - formation water" sections in the compartments, as well as local control over the pressure of the medium in the apparatus, the levels of the "oil - gas" section and "oil - formation water". The technical characteristics of the OG-200S sump are given below.

Oil settler OVD-200

Settler OVD-200 is a horizontal steel cylindrical tank with a diameter of 3400 mm.

General view of the OVD-200 sump

The sump is equipped with an emulsion distributor 2, oil 1 and water 4 collectors made of perforated pipes. The emulsion distributor consists of two combs (double-sided) with four pipes in a row. Holes are located along the lower generatrix of the distributor pipes, under which U-shaped fenders 3 are installed. This arrangement of the holes prevents the accumulation of dirt and mechanical impurities in the pipes and contributes to the uniform removal of the released water. Fenders are designed to dampen the kinetic energy of the flowing emulsion jets, distribute them evenly over the section of the apparatus and prevent mixing of the underlying water layers.

The operation principle of the settling tank is based on gravity settling and on the effect of emulsion flushing, both in the drainage water layer and in the intermediate layer of highly concentrated emulsion, which acts as a kind of coalescing filter. The technical characteristics of the OVD-200 settling tank are given below.

Oil settler OBN-3000/6

The settling tank OBN-3000/6 is also a horizontal steel cylindrical tank with a diameter of 3400 mm. It is equipped with an emulsion distributor 3, oil 1 and water 5 collectors, as well as corresponding fittings for emulsion 4 input, oil 2 and water 6 output. containers. The principle of operation of the sump is based on gravitational settling with relatively horizontal movement and separation of the emulsion into oil and water.

General view of the settling tank OBN-3000/6

The technical characteristics of the settling tank OBN-3000/6 are given below.

Introduction

Horizontal oil settlers with baffles, installed at the OTU, BPS are designed for dehydration of oil with separation of gas remaining in the oil emulsion, designed for nominal pressure from 1.0 to 2.5 MPa and with a temperature of the working medium of not more than 100°C. Settler operation mode - constant.

When operating the loan, it is necessary to follow the instructions for labor protection when performing work in containers and apparatuses, the manufacturer's instructions for the installation and operation of vessels, and the instructions for operating safety devices. Maintenance work on an existing vessel, preparation for survey and technical examination of vessels are gas hazardous, and work on hydraulic testing is of increased danger.

The development of new fields, the absolute annual increase in oil and gas production in our country have no analogues in foreign practice. The rapid development of the domestic oil and gas industry became possible due to the widespread introduction of advanced equipment and technology in the exploration of new oil and gas fields, drilling wells, infrastructure development and field development.

Among these problems stand out such as the development of efficient methods and reliable equipment for deep dehydration of heavy and high-viscosity oils; preparation of oils containing mechanical impurities; increasing the efficiency and reliability of block devices; destruction of trap emulsions; forecasting of technological parameters of oil and water treatment depending on their physical and chemical properties, etc.

The places of primary oil refining are close to the places of oil production.

Currently, in oil fields, for the implementation of the process of preliminary dehydration of oil according to the pressure scheme, mainly settling tanks-water separators of the OG-200 or OG-200s type are used.

The sump is subject to mandatory certification and is designed, manufactured, adjusted, installed, repaired and operated in full compliance with the Rules for the Design and Safe Operation of Pressure Vessels (PB 03-576-03). The sump can be designed and manufactured for almost any pressure and capacity.

1. Technical and technological part

1.1 Purpose, application, technical characteristics and classification of the horizontal sump

A horizontal settling tank with a bottom distributed emulsion inlet is designed to settle oil emulsions in order to separate the latter into their constituent oil and produced water. The following designations are accepted in the cipher: OG - horizontal sump; number 200 - tank volume (in m3) P - with partitions.

The scope is determined by the permissible parameters of the environment to be defended:

median particle size of mechanical impurities - no more than 0.02 mm;

water cut of raw materials - no more than 30%;

water cut of the outgoing oil - no more than 0.5%.

Technical characteristics of the sump:

Marketable oil throughput, t/day - 4000

Operating medium oil, gas, produced water

Working pressure (overpressure), MPa - 0.6

Test pressure (overpressure), MPa - 0.8

Medium temperature, ° С - up to 100

Apparatus volume, m3 - 200

Weight, kg - 48105

In industry, settling is carried out with the help of settling tanks, which are periodic and continuous.

In the direction of suspension flow, sedimentation tanks are divided into radial, horizontal, vertical and inclined, or thin-layer. In radial settling tanks, the suspension is fed to the center of the apparatus and moves to the periphery. In horizontal - it is loaded from one end of the device and moves along it. In vertical systems, the suspension is fed from below and rises, and the upward flow rate must be less than the settling rate of solid particles (sometimes, to accelerate the settling, the initial mixture is fed under a layer of thickening sediment). In inclined - deposition is carried out in packages of plates (or pipes) inclined at an angle of 45-60 °.

The following bottoms are used in vessels: elliptical, hemispherical, torospherical, spherical non-flared, conical flanged, conical non-flared, flat flanged, flat non-flared.

The simplest pressure apparatus for separating water from an oil emulsion treated with a demulsifying agent is a horizontal hollow sump. Depending on the method of introducing the emulsion into this apparatus and the selection of dehydrated oil and separated water, these apparatuses are usually divided into settling tanks with vertical and horizontal flow.

Sometimes, when processing oils at the dehydration stage, it is necessary to separate the free gas released during heating of the oil and some decrease in the total pressure in the system. To separate gas from a heated oil emulsion, special separators are installed in front of settling tanks (or electric dehydrators), or gas is taken directly from the settling tank. Currently, such a basic apparatus with a built-in separator is the OG-200S sump, which is most widely used in the fields both for preliminary dehydration of oil and at the stage of its dehydration and desalting.

Horizontal settling tank OG-200C is a cylindrical tank mounted on a base frame (Figure 1). The settling tank is divided by a partition into two compartments: separation and settling, which communicate with the help of two manifolds-distributors located in the lower part of the body. An emulsion distributor with drain shelves and a gas separator are installed in the upper part of the separation compartment.

In the lower part of the settling compartment, there are two tubular perforated collectors, above which there are box-shaped emulsion distributors. In this part there are also two collectors for steaming the apparatus. In the upper part of the compartment there are four oil collectors connected to the oil outlet fitting from the apparatus. Near the end part of the housing, with the help of a partition and overflow devices, a water-collecting chamber is made, in which an interfacial level regulator is placed.

The settling tank is equipped with technological process parameters control devices, phase interface level regulators, safety and stop valves. For ease of maintenance of devices located in the upper part of the body, the device is equipped with a service platform. The sump works as follows. Heated emulsion oil with a demulsifying agent introduced into it enters the emulsion distributor of the separation compartment and flows down the drain shelves and walls of the compartment to the lower part of the compartment. The gas released from the oil as a result of its heating and pressure reduction passes through the separator and is discharged into the gas gathering network with the help of an oil-gas level regulator.

1 - separation compartment: 2 - settling compartment: 3 - emulsion distributor; 4 - visors: 5 - oil collector; 6 - oil-water level regulator; I - emulsion. II - gas, III - oil, IV - water.

Figure 1-Horizontal settler OG-200S

The oil emulsion from the separation compartment enters the settling compartment through two perforated collectors, passes through the openings of the box distributors and rises to the upper part of the compartment. In this case, oil is washed with formation water and dehydrated. Dehydrated oil enters the collection manifold and is removed from the apparatus.

The water separated from the oil through overflow devices enters the catchment chamber and, with the help of a level controller, formation water - oil is discharged into the drainage water treatment system.

A settling tank with vertical oil flow OVD-200 (Figure 2) is designed to separate water-oil emulsions at high specific loads and the need to obtain high-quality oil, especially at small differences in oil and water densities.

The main element of the sump is a low-pressure inlet switchgear, consisting of two transverse collectors with 16 perforated pipes (four in a row) with fenders below them. The holes in the distributor pipes are made with a variable pitch along the lower generatrix in order to prevent the accumulation of dirt and mechanical impurities and to uniformly drain the separated water. Fenders are designed to dampen the energy of the flowing emulsion jets and prevent mixing of the underlying water layers.

1 - emulsion distributor; 2 - chipper; 3 - oil collector; 4 - water collector; I - emulsion; II - oil; III - water.

Figure 2 - Settling tank with vertical flow type OVD-200 (design VNIISPTneft)

The settling tank OVD-200 is not adapted to work with the release of gas from oil, therefore, in the technological schemes of the OTU,

working according to the pumpless version, there must be a separator in front of it.

Settling tank with horizontal movement of oil OGD-200 is designed for separating stratified flows of coarse water-oil emulsions, in case of possible release of some amount of gas - in settling tanks. The device is designed to work both without a water "cushion", and with it. The settling tank OGD-200 is the simplest and most rational of the devices of this type. The radial end emulsion distributor and the oil collector are made in the form of perforated drums. The water collector is a long perforated pipe to reduce the "slip" effect, which consists in the fact that the emulsion layers adjacent to the water phase acquire increased velocities towards the end of the apparatus, are reflected from the bottom and, moving by inertia, are carried away to the output oil collector. Drainage water taken from these settling tanks is usually returned in the OPF process flow to the oil stream before the preliminary discharge devices.

a - sump type OGD-200: b - sump with end queen cells; c - sump design SibNIINP; I - emulsion; II - oil; III - water.

Figure 3 - Schemes of sedimentation tanks with horizontal flow.

1.2 Device and principle of operation

The sump is made in a monoblock and consists of a sludge block, a service platform, shut-off and control valves and a monitoring and control system.

Settler OG-200 (Figure 4) is a horizontal steel cylindrical tank 1 with a diameter of 3400 mm with elliptical bottoms.

1 - housing, 2 - movable support, 3 - oil collector, 4 - emulsion inlet mother liquor, 5 - steaming line, 6 - fixed support

Fittings: A - emulsion inlet; B - oil output; B - water outlet; G - gas outlet; D - for the regulator; E - manhole; F - for steaming; K - drainage; L - for the safety valve.

Figure 4 - Scheme of the OG-200 sump

The oil emulsion enters the emulsion inlet sump 4, which has holes for emulsion distribution. From the openings of the mother liquor, oil flows in thin streams under the level of formation water in the sump.

Thanks to this design, oil acquires vertical movement over a large area of ​​the apparatus. The dehydrated oil floats up and enters the oil collector 3 located in the upper part of the sump and is discharged from the apparatus through fitting B. Formation water separated from oil enters the right side of the settling tank and is discharged through nozzle B with the help of a float regulator of the interfacial level into the industrial wastewater treatment system.

The settling tank OG-200 is supplied complete with control and measuring devices, which allow automatic regulation of the levels of the "oil - formation water" section in the compartments, as well as local control over the pressure of the medium in the apparatus.

The sludge block is a technological tank with a diameter of 3400 mm (volume 200 m3), installed using three supports on the foundation. For a more complete use of the volume of the tank, it is equipped with a distributing device for introducing an oil-water emulsion, mounted along the axis of the sump. The water collector (a long perforated pipe) is located at the bottom of the tank, and the oil collector is located across the tank in its upper part. The collector has two fittings for the oil outlet, allowing you to conduct technological process in full and partial modes. The tank has manholes, a safety valve, a drainage system.

The sump is equipped with control and regulation devices - pressure gauges, thermometers, an oil-water interfacial level control unit, as well as a water-oil emulsion supply to the sump. For ease of maintenance of devices located in the upper part of the body, the device is equipped with a service platform.

The settling tank works as follows: the oil emulsion enters the emulsion inlet sump 4, which has holes for distributing the emulsion. From the openings of the mother liquor, oil flows in thin streams under the level of formation water in the sump. Thanks to this design, oil acquires vertical movement over a large area of ​​the apparatus. The dehydrated oil floats up and enters the oil collector 3 located in the upper part of the sump and is discharged from the apparatus through fitting B. Formation water separated from oil enters the right side of the settling tank and is discharged through nozzle B with the help of a float regulator of the interfacial level into the industrial wastewater treatment system.

1.3 Organization of maintenance of the horizontal sump

1) When checking the operation of the vessel (at least once per shift), it is necessary to check:

tightness of external and internal flange connections

completeness of fasteners, no breakage and damage

tightness and serviceability of devices and automation equipment

tightness of connections and serviceability of pressure gauges

tapping the safety valve

the tightness of the connections and the serviceability of the valves, by inspection, opening / closing by 2-3 turns with a return to the working position, the completeness of the fasteners, the presence of a tag, indicating the number according to the technical scheme.

the presence at the workplace of the scheme for switching on the vessel indicating the source of pressure, parameters, its working environment, fittings, instrumentation, automatic controls, safety and blocking devices. The scheme must be approved by the management of the organization.

the presence of a safety valve passport with the calculation of its throughput.

2) The technical examination of the vessel is carried out by the supervising person appointed by the order, with the participation of the person responsible for the good condition and safe operation of the vessels. Technical examination is carried out in accordance with the requirements of the Rules for the Design and Safe Operation of Pressure Vessels (PBO3-576-03).

hydraulic test (HI) - at least once every 8 years by test pressure (1.25 Р dir, taking into account the allowable stresses for the vessel material), time

exposure under test pressure - 5 minutes

internal inspection (VO) - 1 time per year - at a corrosion rate of more than 0.1 mm / year, and 1 time in 2 years at a corrosion rate of less than 0.1 mm per year.

3) The technical examination of vessels is carried out according to the annual schedule approved by the chief engineer.

4) The results of the technical examination are recorded in the passport of the vessel by the person who conducted the examination, indicating the permitted parameters of the operation of the vessel and the timing of the next examination and signed by the members of the commission.

5) On the vessels, recognized during the technical examination as fit for further operation, information is applied in accordance with clause 5.4 of this instruction.

6) For vessels that have worked out the design service life established by the design, manufacturer, other RD or for which the design (permissible) service life has been extended based on the technical report, the scope, methods and frequency of technical examination should be determined based on the results of technical diagnostics and determination of the residual life performed by a specialized organization, or organizations licensed by Rostekhnadzor to conduct an industrial safety review of technical devices (vessels).

7) The results of the industrial safety examination are recorded in the vessel passport by the person responsible for the good condition and safe operation of the vessel, based on the conclusion received.

1.4 Procedure for starting and stopping the horizontal settler

A permit for commissioning a vessel subject to registration with the Gosgortekhnadzor of Russia is issued by an inspector after its registration on the basis of a technical examination and inspection of the organization of maintenance and supervision, which controls:

availability and serviceability in accordance with the requirements of these rules of fittings, instrumentation and safety devices;

correct inclusion of the vessel;

availability of certified service personnel and specialists;

availability of job descriptions for persons responsible for exercising production control, for compliance with industrial safety requirements during the operation of pressure vessels, responsible for the good condition and safe operation of vessels;

instructions for the mode of operation and safe maintenance, replacement magazines and other documentation provided for by the Rules.

A permit to commission a vessel that is not subject to registration with the Gosgortekhnadzor of Russia is issued by a person appointed by order of the organization to carry out production control over compliance with industrial safety requirements for the operation of pressure vessels, based on the manufacturer's documentation, after technical examination and verification service organizations. Permission to put the vessel into operation is recorded in its passport.

The vessel can be put into operation on the basis of a written order from the administration of the organization after meeting the safety requirements.

After receiving a written permission from the administration of the organization, the person responsible for the good condition and safe operation of the vessel instructs the maintenance personnel to start the vessel in a written order.

To start the sump, you must:

open the valves on the discharge line of released water and settled oil;

open the valve on the emulsion input line; turn on the monitoring and control system;

adjust the device adjuster and switch it to automatic mode.

Shutdown and hydraulic testing for density in winter is carried out in accordance with the "Regulations for conducting in winter start-ups, shutdowns and leak tests of chemical, oil refining and petrochemical equipment, as well as gas fields of plants No. 1).

Settling tanks are stopped by a written order of the head responsible for the operation of pressure vessels. The positions of the shut-off and control valves and the sequence of stopping the settling tanks 0-1,2,3 are similar to each other.

Stopping of sedimentation tanks is carried out in the following sequence:

close the valve on the oil inlet line to the sump;

close the valve on the oil outlet line from the sump;

close the valve on the bottom water discharge line;

open the valves to relieve pressure in the drainage tank;

reduce the pressure to atmospheric;

open the air vent.

Release the vessel from the working medium into a drainage container; If the sump is taken out for repair or to prepare it for technical examination, then it is necessary to install plugs in the following places: on the oil inlet and outlet lines, on the bottom water discharge line, on the drainage lines.

Before installing the plugs, it is necessary to issue an order for carrying out gas hazardous work for the installation of plugs, with an entry in the "registration log for permits for the production of gas hazardous work", and also make an entry in the "logbook for installing and removing plugs".

The plugs used to shut off the vessel must be factory-made, an inventory number, conditional, must be stamped on the shank. After stopping the sump, it is necessary to make entries in the shift log for the inspection of pressure vessels. If the sump is put into reserve, then it is not necessary to install plugs.

Emergency stop of the vessel.

The vessel must be immediately stopped in the following cases, provided for by the operating mode and safe maintenance instructions, in particular:

if the pressure in the vessel has risen above the permitted level and does not decrease, despite the measures taken by the personnel;

when a malfunction of safety devices against pressure increase is detected;

upon detection of leaks, bulges, rupture of gaskets in the vessel and its elements working under pressure;

if the pressure gauge malfunctions and it is impossible to determine the pressure using other instruments;

when the liquid level drops below the permissible level in vessels with fire heating;

in case of failure of all liquid level indicators; in case of malfunction of safety interlocks; in the event of a fire that directly threatens the pressure vessel.

The procedure for emergency shutdown of the vessel and its subsequent commissioning should be specified in the instructions.

Vessel emergency stop:

The emergency shutdown of the sump is carried out without the order of the person responsible for the good condition and safe operation of pressure vessels;

The procedure for emergency shutdown of settling tanks is similar to this instruction, if necessary, plugs are installed, if stopping is impossible due to fire or for other reasons, then the personnel servicing pressure vessels must act according to the "Accident Elimination Plan, fire point at the OTU, BPS or depressurization of one of settling tanks".

About the emergency stop of the vessel, immediately inform the engineer responsible for the good condition and safe operation of pressure vessels, the workshop administration, the shift supervisor of the CITS;

The reasons for the emergency stop of the vessel should be recorded in the shift log for the inspection of vessels operating under pressure and in the shift log;

After the elimination of the accident and the elimination of all malfunctions, preparation for start-up and start-up of settling tanks for operation is carried out in accordance with these instructions, by written order of the engineer responsible for the good condition and safe operation of pressure vessels.

Starting, stopping the vessel in winter:

starting, stopping, testing of the vessel in winter is carried out only in extreme cases, forced by production conditions or emergency situations.

the launch of the vessel in winter should be carried out in accordance with the schedule:

Figure-5. Vessel start-up schedule in winter time.

P1=Pwork. P2 \u003d 0.35 Rwork.

minimum wall temperature at which steel and its joints are allowed to work under pressure Р1, И=-55°С

minimum air temperature at which start-up is allowed

pressure vessel Р2.12=-50°С.

When the vessel is stopped in winter, the decrease in pressure with a decrease in the wall temperature must meet the requirements of the schedule. The rate of rise or decrease in temperature is recommended no more than 30°C/hour. Achievement of pressure P1 and P2 is recommended to be carried out gradually by 0.25 Rrab. within an hour with 15-minute holding pressures on the steps: 0.25Rrab., 0.5Rrab. and 0.75 Rrab. If it is necessary to test the vessel in winter, all the requirements for starting and stopping the vessel must be met.

1.5 Typical malfunctions and their solutions

Table 1 - Typical malfunctions and ways to eliminate them

Typical malfunctions	Reason for failure		Troubleshooting Methods
1	2		3
1. The bolts on the flanges are crumpled, the thread is stripped	Uneven tightening. Unstable working pressure.		Bolt replacement. Strengthening the control of the operating mode.
2. Failure of the flange connection (flange socket)	Corrosion. Deformation of the flanged pipe		Flange replacement or welding
3. Violation of tightness in the joints of the valve	Gasket wear. Spindle nut thread wear	Gasket replacement. Valve replacement
4. Leaks in flanges	Gasket wear	Replacing gaskets. Valve replacement
5. Body defects (dents, bulging)	Pressure increase, mechanical influences, aging of the body material	Temporary adjustment until the next overhaul
6. Cracks	Mechanical influences, aging of the body material	Temporary overlay until the next overhaul without mechanical impact
7. Corrosion inside the case	Aggressive environment inside the vessel	Cleaning, temporary overlay, indications for overhaul
8. Violation of the integrity of the welded joint (leaks)	Weld defects, mechanical influences, operating pressure difference	Performing current repairs

1.6 The order of delivery of equipment for repair

The transfer of equipment for repair and acceptance after repair are carried out in accordance with the acceptance certificate.

The head of the repair shop (if the repair was carried out by the repair shop) or the chief mechanic of the shop (if the repair was carried out by the oil preparation shop) is responsible for the time and quality of the repair.

The head of the workshop (installation) is responsible for carrying out fire prevention measures during the repair.

The results of repairs and information about the condition of equipment and apparatus are entered by the mechanic in the repair card, passport or journal, which are stored in the shops.

Acceptance of equipment from repair is carried out by a special commission appointed by order of the enterprise. The commission should include representatives of the technological service, the service of the chief mechanic, the chief power engineer, safety engineering, and the trade union organization.

The commission checks the compliance of the volume of work performed with the defective act, which is drawn up before the equipment or installation is handed over for repair. As-built documentation is checked (certificates of welding works, certificates of materials used in the repair, correctness of filling in repair logs, results of hydraulic tests, etc.).

With a positive decision of the commission, the commissioning of the equipment is allowed.

Before putting the equipment into operation after repair, the plugs are removed, with which the device was disconnected from the existing communications. The correctness of the removal of the plugs is checked by the head of the installation.

After filling the equipment with oil or other product, all flange connections are carefully checked for tightness.

The sump body consists of a welded shell with elliptical bottoms welded from the ends.

Chassis malfunctions eliminated during repair:

defects and corrosion of the base metal;

rivulet corrosion in the lower part of the body (in the form of longitudinal grooves);

deformation of the case (bulge dents, offset of the edges of the sheets, etc.);

Flange defects:

damage to the grooves for the sealing rings;

defects and corrosion of welds;

flange deformation.

Almost all of the above defects in the body, flange connections and internal elements of the sump associated with corrosion, wear and damage can be eliminated by welding and surfacing; the deformation of the elements can be eliminated by editing.

1.7 Repair procedure

To maintain the pressure vessel in good condition, the management of the structural, shop subdivision is obliged to organize its repair.

Delivery for overhaul, as well as the issuance of vessels from repair is carried out in accordance with acceptance certificates. For the production of repair work in the prescribed manner, an order is issued - admission.

Unscheduled repairs should be carried out on the basis of written requests from the head of the workshop unit with the obligatory execution of an act of investigating the reasons that led to the unscheduled repairs.

Commissioning must be carried out by order of the head of the workshop unit.

Repair using welding (soldering) of pressure vessels and their elements is carried out according to the technology developed by the manufacturer or the repair organization before the start of work and, if necessary, agreed with the CO UTO RGTN, duly certified personnel. The results of the repair are recorded in the vessel passport.

Prior to the start of work inside a vessel connected to other operating vessels by a common pipeline, a scheme for installing plugs by a person responsible for the good condition and safe operation of the vessel (or by a person replacing him) must be developed and approved by the head of the workshop, the vessel must be separated by plugs installed in in accordance with the requirements of the Rules of Rostekhnadzor of the Russian Federation PB 03-576-03 with an entry in the "Installation log - removal of plugs".

When working inside the vessel (internal inspection, repair, cleaning, etc.), safe lamps with a voltage of not more than 12 V must be used, and in explosive environments - in an explosion-proof version.

Works inside the vessel (internal inspection, repair, cleaning, etc.) must be carried out according to the order - permission to carry out work of increased danger in accordance with the requirements of the labor protection instructions for the types of work performed, developed in the prescribed manner.

IT IS FORBIDDEN:

repair the vessel and its elements under pressure;

tap the walls, welded and detachable joints of the vessel and its elements under pressure;

operate the vessel with a faulty control panel;

operate the vessel if any technical parameters do not correspond to the passport ones;

store cleaning, flammable materials at the service site;

use (heat the vessel, equipment, pipelines with open fire;

use a faulty tool when servicing the vessel.

1.8 Installation of equipment after repair

All construction and installation works are carried out in three stages:

1. Preliminary preparation of construction: checking and studying technical documentation, clearing the territory, planning

platforms, construction of underground ways, etc.;

2. Carrying out underground works: arrangement of trenches, pits for equipment foundations, arrangement of foundations and permanent underground utilities;

3. Carrying out ground works: installation of equipment and pipelines, commissioning, landscaping.

The installation of the vessel is designed at the site of any field or workshop. Vessel piping to existing pipelines is carried out according to specifications.

Preparatory work before installation:

1. During installation, it is not allowed to carry out welding work on the vessels, unless there are instructions from the manufacturer for this.

2. Slinging must be done using a special device.

3. Leveling must be done using the adjusting screws. At the sliding support of horizontal vessels, the foundation must be fixed with a lock nut with a gap of 1-2 mm.

4. Vessels and electrical equipment are grounded.

5. Before installing the stud nuts, the washers are checked for workmanship. Tighten the studs evenly.

6. All inlet and outlet pipelines must be free of dirt before connection.

7. Before putting the device into operation, it is necessary to remove air by purging with an inert gas. (Purge with steam is allowed).

When accepted for installation, vessels and apparatuses are subjected without disassembly into assembly units of the part and checked:

completeness

no damages, shells, cracks

compliance of equipment with the requirements of technical documentation

fittings have plugs and gaskets.

Installation takes place as follows:

1. Before transportation, a concrete platform is mounted (to install the vessel);

2. Piles and lodgements are mounted on which the vessel is installed;

3. The vessel is installed with the help of a GPM (lifting mechanism, with a lifting capacity of over 50 tons). GPM can be a Japanese KATO crane, or KRUPP (crane with a lifting capacity of 30 tons);

4. The vessel is tied to the supply pipelines according to the scheme:

Liquid inlet to the sump - liquid outlet from the sump - gas outlet;

After the installation of the vessel is completed, it is launched.

1.9 Hydraulic test after repair

A hydraulic test is a necessary procedure that indicates the reliability of pressure equipment throughout its entire service life, which is extremely important, given the serious danger to life and health of people in case of malfunctions and accidents.

Hydraulic testing of newly installed vessels during technical examination may not be carried out if less than 12 months have passed since such a test at the manufacturer's plant, the vessels were not damaged during transportation to the installation site and their installation was carried out without the use of welding or soldering of elements operating under pressure .

The technical examination of the vessel is carried out by a person in charge of supervision, appointed by order for TYPE "LNG". Terms of technical examination are established by the "Rules for the Design and Safe Operation of Pressure Vessels":

hydraulic test (HI) - at least 1 time in 8 years by test pressure (1.25 Rrazr., taking into account the allowable stresses for the material of the vessel), exposure time under test pressure - 5 minutes;

internal inspection (IO) of the sump - once a year - at a corrosion rate of more than 0.1 mm / year;

external and internal examination by a specialist of an organization licensed by the Gosgortekhnadzor of Russia - at least 1 time in 4 years.

The procedure for conducting technical examination and diagnosing a vessel is carried out in accordance with the requirements of: Rules of Rostekhnadzor RF PB 03-576-03; standard of LLC "LUKOIL - Western Siberia" STP 02-02-03 "Cleaning of tanks, vessels, apparatus and disposal of mechanical impurities" "Regulations on the relationship between the technical supervision service and structural, shop divisions of the TYP "Langepasneftegaz" during the technical examination of vessels" "Instructions on the safe conduct of gas-hazardous work" and Instructions for the safe conduct of work in closed containers, approved by the First Deputy - Chief Engineer of the TIP "Langepasneftegaz".

A vessel that has completed its design service life must be subjected to a full technical examination - industrial safety expertise in the scope established by the LNG type regulations. (RSC - 9 years according to the instructions of the RTN RF, based on equipment depreciation rates).

Water or other non-corrosive, non-poisonous, non-explosive, non-viscous liquids may be used for hydraulic testing.

In cases where it is impossible to conduct a hydraulic test (large loads from the weight of water on the foundation, interfloor floors, difficulty in removing water, the presence of a lining inside the vessel that prevents the vessel from filling with water), it is allowed to replace it with a pneumatic test (air or inert gas) at the same test pressure . This type of test is allowed only if the results of a thorough internal examination and verification of the strength of the vessel by calculation are positive.

Before internal inspection and hydraulic testing, the vessel must be installed, cooled (warmed), freed from the working medium that fills it, disconnected with plugs from all pipelines connecting the vessel with a pressure source or with other vessels, and cleaned to metal.

Lining, insulation and other types of corrosion protection should be partially or completely removed if there are signs indicating the possibility of defects in the vessel metal under the protective coating (leakage of the lining, traces of wetting of the insulation, etc.).

Before a hydraulic test, all fittings must be thoroughly cleaned, taps and valves lapped, covers, hatches, etc. tightly closed.

When working inside the vessel (internal inspection, repair, cleaning, etc.), spark-proof lamps with a voltage of not more than 12 V should be used, and in explosive environments - in explosion-proof design. The use of kerosene and other flammable lamps is not permitted.

Hydraulic test is carried out with satisfactory results of internal inspection.

Hydraulic testing of vessels operating at a wall temperature of up to 200 ° C, during periodic inspection, should be carried out with test pressure.

Hydraulic testing of vessels operating at temperatures from 200 to 400 ° C is carried out at a pressure exceeding the working one by at least 1.5 times, and vessels operating at temperatures above 400 ° C - at a pressure exceeding the working one by at least 2 times .

Before increasing the pressure during a hydraulic test, it is necessary to make sure that there is no air in the vessel. If for the hydraulic test the vessel was filled with cold water and dew appeared on its walls, then the test should be carried out only after the walls of the vessel have dried.

During a hydraulic test, the pressure must be controlled by two pressure gauges. Both pressure gauges are selected of the same type, measurement limit, the same accuracy classes, scale intervals.

The exposure time of the vessel under test pressure is set depending on the wall thickness, with a thickness of up to 50 mm, the exposure time is 10 minutes. Then the pressure gradually decreases to the working one, at which the boiler supervisor inspects the vessel, paying special attention to rivets and welds. Tapping of rivet seams while the pressure vessel is under pressure is prohibited.

The vessel is considered to have passed the hydraulic test if it is not detected: leaks, cracks, tears, sweating in welded joints and on the base metal; leaks in detachable connections; visible residual deformations, pressure drop on the pressure gauge.

The vessel and its elements, in which defects were revealed during the test, after their elimination, are subjected to repeated hydraulic tests with test pressure.

If there are signs of water passing through the outer insulation (wetting, swelling), it is completely or partially removed.

During hydraulic testing of vessels with reinforcing rings, the exit of water through the control holes is a sign of a leaky seam.

If during the test blows, noise and knocking are heard inside the vessel, or if there is a sharp drop in pressure, then the hydraulic test is stopped and the vessel is inspected to determine the causes of their occurrence and possible damage.

During an extraordinary survey of the vessel after repair or reconstruction, special attention should be paid to checking the documentation confirming the quality of the work performed and the compliance of the materials with the requirements of the Rules.

When surveying the vessel after dismantling and installation at a new location, special attention is paid to possible damage to the vessel elements during transportation and installation.

An extraordinary survey of the installed vessel after its inactivity for more than one year or storage in a warehouse for more than three years is carried out in the same way as the periodic one, with special attention paid to possible corrosion damage.

In case of an extraordinary survey of the vessel, before applying a protective coating, a thorough check of the condition of the elements on which the coating is applied is carried out.

Maintenance personnel are obliged to strictly follow the instructions for the repair of vessels and their safe maintenance and timely check the proper operation of shut-off valves, instrumentation and safety devices.

2. Settlement part

2.1 Calculation of a shell operating under excessive internal pressure

The main structural elements of the vessel to be calculated are the cylindrical shell and elliptical bottoms. The calculation was made based on the minimum actual thicknesses of the elements, determined from the results of thickness measurements, for operating conditions and for hydrotesting.

Estimated parameters.

Pwork=0.6 MPa - working pressure;

Рraz=0.1 MPa - permitted pressure;

Рprob=1.3 MPa - test pressure (hydraulic);

Working environment = 20°С, - 45°С - working medium temperature;

Dimensions:

Length = 25420mm;

Diameter =3424mm;

The volume of the apparatus \u003d 200 m 3;

Weight = 54000 kg.

Т= +100°С - design temperature;

D= 3400 mm - inner diameter of the shell;

L= 22500 mm - the length of the cylindrical part of the body;

S=12mm S1=S2=16mm - passport thickness of the shell, bottoms;

Smin=10.2mm, SD1min=14.2mm, Smin=14mm - the actual minimum thickness of the shell, bottoms;

С=2 mm - corrosion allowance;

Material - steel 09G2S;

Medium - oil, gas, formation water;

Position - horizontal;

Operating mode - continuous; |δ|=140MPa, |δ|20 - allowable stresses at design temperature and at 20°C, respectively.

Permissible stresses for hydraulic testing conditions

where: n t \u003d 1.1 - safety factor for the yield strength for hydraulic test conditions.

(2.2)

Where φρ=1 - strength factor of the weld

Permissible internal overpressure for hydraulic testing conditions:

(2.3),

Strength conditions:

Pwork=0.6 MPa< [р] =0,67 МПа

RG.calc=0.67 MPa< [р] г =1,3 МПа

The strength condition is met.

2.2 Calculation of an elliptical bottom operating under excessive internal pressure

Permissible internal overpressure for operating conditions:

(2.4)

Where φρ=1 - strength factor of the weld;

R=3000 mm radius of curvature at the top of the elliptical bottom.

Permissible internal overpressure for hydraulic testing conditions:

(2.5),

Strength conditions:

Pwork=0.6 MPa< [р] =1,4МПа

RG.calc=0.67 MPa< [р] Г=2,5МПа

Based on the strength calculations, it was found that the sump satisfies the strength conditions at operating pressure Р=0.6 MPa and temperature Т=100 С

Calculation of the predicted service life of the sump.

The assessment of the vessel resource was carried out for the cylindrical shell, as the main bearing element of the vessel, which is, at the same time, the most loaded, from the condition of the presence of static stress, where the main damaging factor is corrosion wear.

The calculation is performed according to the formula:

where P = 0.6 MPa is the working pressure of the vessel;

Г - estimated resource, in years;

SF=10 mm - the actual minimum thickness of the metal of the element being evaluated;

Sotb - rejection thickness of the element, mm;

operating time - 30 years;

a = 0.15 mm/year - corrosion wear rate;

C = 2 mm - corrosion allowance;

For the rejection thickness, capable of ensuring trouble-free operation of the vessel in the most loaded condition, the calculated thickness of the shell wall is taken:

(2.7)

Then the predicted service life of the sump, from the condition of the presence of static loading and general corrosion wear as the main damaging factor, at an operating pressure of 0.6 MPa will be 5 years. Taking into account the obtained predicted value of the life of the sump, it is possible to set as an inter-diagnostic period - the maximum allowable period, equal to 5 years.

3. Occupational health and safety when repairing equipment

Repair work of the sump is allowed to be carried out if there is a work order, a permit and an act drawn up by a commission consisting of the chief engineer, the head of the repair work, and the safety engineer.

Persons at least 18 years of age who have passed a medical examination, trained and certified in the prescribed manner for the right to service vessels are allowed to perform repair work. The admission of personnel to the maintenance of vessels must be issued by order for the workshop with the familiarization of the responsible maintenance personnel with the signed signature.

Periodic testing of knowledge of the personnel servicing the vessels should be carried out at least once every 12 months.

Extraordinary testing of knowledge of the personnel serving the vessels is carried out:

when moving to another organization,

in the event of a change in the instructions for the mode of operation and safe maintenance of the vessel,

at the request of an inspector of the Gosgortekhnadzor of the Russian Federation or a person in charge of supervision. In case of a break in work in the specialty for more than 12 months, the service personnel, after checking their knowledge, must undergo an internship of at least 10 work shifts before being allowed to work to restore practical skills.

In case of an unsatisfactory result of the knowledge test, the employee must be removed from the independent maintenance of vessels.

Responsibility for ensuring fire safety measures during hot work is assigned to the manager on whose territory hot work will be carried out.

Prior to the start of hot work, the person responsible for their conduct is obliged to coordinate these works with the local fire brigade, safety engineering services and analyze the air for the absence of explosive concentrations of gas (vapours) with devices, organize the implementation of all fire safety measures and provide the place where hot work is carried out with the following fire extinguishing equipment:

felt felt or asbestos cloth size 2 * 1.5 m - 2 pcs;

fire extinguishers OU-8 or OUB-7 and buckets - 10 pcs;

foaming agent, fire hoses and foam generators (water is supplied from a stationary fire extinguishing system) - 2 sets;

shovels and crowbars - 5 pcs.

A welder must not start hot work without a written

permission issued by the chief engineer or manager and agreed with the fire department. In addition, he must verify that all fire safety requirements specified in the permit are met.

In places where hot work is carried out and on sites where welding units, instrumentation are installed, the following fire safety measures must be taken:

the possibility of penetration of flammable gases and vapors of oil products to the place of performance of these works is completely eliminated;

at a distance of 15 m from the site where hot work is performed and the places where welding units are installed, the territory must be cleared of debris of combustible objects, various oil products;

the place where oil products were spilled must be covered with sand or earth with a layer of at least 5 cm;

within a radius of 5 m from the place of hot work there should be no dry grass;

be careful when moving the assembly wires, avoid sparking of the wires (if their insulation is insufficient or broken).

Hot work must be immediately stopped if combustible gases or vapors of oil products are detected nearby. At the end of hot work, the place where they are carried out must be carefully checked and cleaned of hot cinders, scale or smoldering objects, and, if necessary, watered.

When extinguishing kerosene, gasoline and oil, ignited electrical wires, as well as rooms where calcium carbide is located, it is forbidden to use water and foam fire extinguishers. In such cases it is necessary to use sand and carbon dioxide or dry fire extinguishers.

For trouble-free and safe operation of the vessel, fittings, instrumentation, safety devices (PPK valve), you must strictly comply with the requirements and know: the vessel piping scheme and the installation as a whole;

technological regulations of the installation and parameters of the regime card; technical characteristics, design features, purpose, mode of operation of the vessel;

operating instructions for safety devices (PPK); a plan for the elimination of possible accidents;

this manual on the mode of operation and safe maintenance of the vessel with familiarization against signature.

Dismantling of settling tanks installed for internal inspection, cleaning, repair, etc., can be carried out only after they are freed from the product of production and disconnected with plugs from all pipelines connecting them to pressure sources or other process equipment.

Sumps at the installation site must be earthed.

Grounding must be carried out in accordance with the "Rules for the protection against static electricity in the chemical, petrochemical and oil refining industries." Lightning protection of devices must be carried out in accordance with the "Guidelines for the design and installation of lightning protection of buildings and structures."

Connection of grounding conductors to the separator must be carried out by welding. In this case, the joint indicated on the assembly drawing must be cleaned to a metallic sheen, and after welding, painted to protect against corrosion.

Before starting work, the maintenance personnel are obliged to bypass the technological installation, make sure that the vessel and its equipment are in good condition.

After that, the maintenance personnel are obliged to study the entries in the journal of inspections and checks of pressure vessels for the previous shift, and then make records of the inspection of vessels and their equipment with a signature on the acceptance of the shift.

In the event of a malfunction, the maintenance personnel must immediately inform the shift supervisor and responsible for the good condition and safe operation of pressure vessels, to whom the maintenance personnel directly reports. The person responsible for the safe operation of the vessels takes measures to eliminate violations and malfunctions.

Conclusion

This course work covers such questions as: what is the horizontal sump intended for, in what industry can it be used, what it is, how it is classified, its principle of operation. The issues of control, maintenance, in which cases the vessel is stopped are studied. I also considered such items as typical malfunctions and ways to eliminate them, how they carry out repairs, installation of equipment, then such a necessary procedure that indicates the reliability of a pressure vessel - hydraulic testing.

She made a calculation of the shell - a cylindrical shell of a closed profile with an open end and a calculation of the elliptical bottom operating under excessive internal pressure. This calculation predicts the service life of the horizontal OG200P sump.

In the final paragraph of the course project, measures for labor protection and safety in the repair of equipment are considered.

List of used literature

1. Bukhalenko E.I. Oilfield equipment - M.: Nedra, 1990

2. Lutoshkin G.S. Collection and preparation of oil, gas and water. Textbook for technical schools. 3rd ed., revised. and additional -M., Nedr, 1983-224 p.

3. Lutoshkin G.S. Collection and preparation of oil, gas and water. Rev. 2nd edition And extra. M.: Nedra, p.319, 1983

4. Lutoshkin G.S. Collection and preparation of oil, gas and water. M., "Nedra", 1977, 192 p.

5. Raaben A.A., Shevaldin P.E., Maksutov N.Kh. Repair and installation of oilfield equipment: Proc. For technical schools. 3rd ed., revised. And extra. -M.: Nedra, 1989. -383 p.: ill.

6. L.G. Chicherov, G.V. Molchanov, A.M. Rabinovich and others. Calculation and design of oilfield equipment: Proc. Allowance for universities. - M.: Nedra, 1987. - 442 p.

7. Instructions for the mode of operation for maintenance of vessels operating under pressure (horizontal sump) DNS-3.

8. Passport of the pressure vessel (horizontal sump)

9. Rules for the technical operation of tanks and instructions for their repair / State Committee of the USSR for the provision of petroleum products. - M.: Nedra, 1988, -269 p.

10. Application. Instructions for the repair and safe maintenance of pressure vessels (Sump) DNS-3, E-10.