Transformer Oil Regeneration Plant CMM-6R

Technical specifications

Parameter	Units	Value
Capacity	m3/hour	1
Maximum allowable oil temperature	оС	90
Outlet pressure	bar	1,5
Oil heater power	kW	50
Vacuum system nominal suction rate	m3/hour	280
Fuller’s earth load	kg	900
Maximum power consumption	kW	95
Electric parameters
Phases		3p+1N+PE
Voltage	V	415
Frequency of AC	Hz	50
Connections
Oil inlet	DN	25/Camlock C100
Oil outlet	DN	25/Camlock C100
Transformer evacuation inlet	DN	Flange DN100
Vacuum pump exhaust	DN	32/G1 1/4
Reactivation exhaust	DN	50/G 2”
Filter element specifications
Strainer (mesh filter)	hm	100
Pre-filter with filter element	hm	25
Regeneration section filter with filter element	hm	0,2х2
Fine filter with filter element	hm	5
Dimensions (without trailer)
Length	mm	10680
Width	mm	2090
Height	mm	2110
Weight	kg	8000

Parameters of processed oil

Parameter	Unit	Value
In 1 thermal vacuum degassing cycle
Moisture content	ppm	5
Volumetric gas content	Vol %	0,1
In 3 thermal vacuum degassing cycles
Moisture content	ppm	3
Volumetric gas content	Vol %	0,05

Parameters of used oil after regeneration

Parameter	Unit	Value
In 1 thermal vacuum degassing cycle
Moisture content	ppm	5
Volumetric gas content	Vol %	0,1
Acid number, as per IEC 296; ASTM D-664	mg КОН/g	0,01
Corrosive sulfur as per ISO 5662; ASTM D-1275		None
Breakthrough voltage, as per IEC 156; ASTM D-1816	kV	70
Interfacial tension, at 25oС as per ISO 6295; ASTM D-2285	N/m	45
Dissipation factor at 90oС as per IEC 247; ASTM D-924		0,001

UNIT DESCRIPTION

Composition of the unit:

• The unit is a frame with the following components:
• Oil degassing section (also referred to as degasser in this manual)
• Oil regeneration section
• Operator room

• The unit is used during installation, maintenance and operation of oil-filled high voltage equipment (power transformers, high-voltage switchgear, etc.).
• The unit is designed for processing of electric insulation oils and servicing of transformers.

The process of dielectric oil treatment includes the following:

• Removal of dissolved gases.
• Removal of free and dissolved water.
• Removal of particulate matter.
• Removal of oil degradation products.

Servicing of transformer includes:

• Evacuation of the transformer.
• Heating of the transformer and its core with hot oil.
• Removal of sediment from the coils of the transformer.

Operation process

• The principle of processing the dielectric oil is heating the oil and passing it through a vacuum vessel. The heat and low pressure reduce partial pressure of water and gases in the oil. This facilitates evaporation of water and emission of gases and their removal.
• Degradation products are removed by sorbent (Fuller’s earth. The oil is directed to vessels, containing the sorbent. When the oil contacts the sorbent, the oil is filtered on molecular level. The oil’s chemical and physical properties are thus restored.
• Sorbent is reactivated in the Sorbent reactivation mode. This method allows reusing the sorbent without the need to replace it.

Methods of operation

The oil may be treated as follows:

• Connection of the unit’s inlet and outlet to an oil vessel and circulating the oil in the vessel.
• Connection of the unit’s inlet and outlet to a transformer and circulating the oil in the transformer.
• Connection of the unit’s inlet to an oil vessel, and connection of the outlet to a transformer.
• Connection of the unit’s inlet to one oil vessel and the unit’s outlet to another oil vessel.
• For evacuation of transformer or other equipment, the unit is equipped with a vacuum evacuation port.

UNIT DESIGN

The unit consists of two primary operating sections: the degasser and the regeneration section. These sections are interconnected by pipelines. The unit is optionally equipped with a system to control oil level in the transformer, the TSS (Transformer Security System). The unit is controlled by an industrial PLC controller, which is programmed for operation and control of the unit’s components.

Location of the unit’s main components

Electric control system

• Automation and electric control system consists of two power cabinets and a control cabinet.
• Power cabinet is installed directly on the unit’s frame. The cabinet contains communication equipment: magnetic starters, motor protection automation, heating power control section and automatic switches (circuit breakers), while the control cabinet contains the controller with a number of digital and analogue inputs and outputs.
• Automatic protection of motor drives (Q1 – Q6) are installed for protection of the motor from current overloads and short circuits. The magnetic starters (КМ2 – КМ7) move the drives in accordance with the logic programmed in the controller.
• The power of electric heater is controlled by a solid state relay and depends on the current throughput and temperature set by the operator. The heaters are protected from short circuit by a triplepole switch.
• The control cabinet is located in the operator room and contains power supply, reducing transformers, power supply filter and automatic protection. The front panel contains power supply and phase control lights, emergency stop button and the control touch panel.

The control panel in the operator room

Components of the control system

Pos	Item	Description
1.	Touch panel	The panel is used to control the unit’s components
2.	Manual circuit breaker lever	Disconnects power supply
3.	“Phase control” light	The light is on if power is connected correctly
4.	“Power” light	The light is on when the unit is powered
5.	“Stop” button	Emergency stop button

Using the operator touch panel

• The control system is based on a controller and a touch panel. The controller contains a set of instructions to control the logic of actuator operation.
• The touch panel is a device for display and control. The panel allows the operator to view main parameters, such as the temperature, pressure, vacuum and throughput, as well as the status of actuators. The panel is also a means to control the processes in the controller’s memory.
• The control system is designed for the following modes of operation:

Mode		Specifics
«СHARGING» mode – filling the unit.		In this mode, the vessels of the unit are filled to the maximum level, and air is released from pipelines.
Oil regeneration/degassing mode: «DEGASING/REGENERATION»	Oil degassing	Moisture, gases and solids are removed from transformer oil in this mode.
	Oil regeneration	Oil is regenerated and degassed in this mode.
	Sorbent reactivation	Sorbent properties are restored in this mode. All contaminants within the sorbent are burned out, those that cannot be burned out are collected in waste trap. While this mode is active, the unit continues to degas the oil in the transformer.
Equipment testing and adjustment mode: «MANUAL».		All components of the unit may be turned on or off in this mode.

• Mode of operation is selected from the start screen

1. – Start screen; 2. – Charge mode selection button; 3. – Degassing mode selection button; 4 – Transformer Safety System selection button; 5 – Manual mode selection button

Degassing section flow diagram

Degassing section components

Pos	Item	Description
MV 1 ; MV 1.1	Ball valves	Stops oil flow into the unit
V1	Automatic oil inlet valve	Stops oil flow into the unit.
P1	Centrifugal pump	Pumps oil into the unit.
MF1	Coarse filter	Stops particles larger than 100 micron
LS1	Oil level sensor	Stops the unit when no oil is present at inlet
MV2	Ball valve	Drains oil from coarse filter
FCV	Regulation valve	Adjusts the flow rate of oil input
G1	Pressure sensor	Indicates pressure at coarse filter inlet
SV1	Ball valve	Sampling valve for incoming oil
F1	Fine filter	Stops particles larger than 25 micron
AV1	Air release valve	Discharges air from filter
MV3	Ball valve	Drains oil from fine filter
G2	Pressure sensor	Indicates pressure at coarse filter outlet
Н	Oil heater	Heats the oil to operating temperature
MV4	Ball valve	Drains oil from the heater
T1	Thermistor	Controls oil heating
T2	Thermostat	Prevents oil overheating
FS1	Flow switch	Controls oil heating and prevent oil heater from engagement with no oil flow
LC1	Flow counter	Used for flow control and counting of total treated oil
VC	Vacuum column	Boiling and emission of water and gases from the oil
V3	Automatic ball valve	Supplies the oil to regeneration section
V2	Automatic ball valve	Stop oil line to the column
V4	Automatic ball valve	Sends oil to the unit after regeneration
V5	Angle valve	Prevents oil from being sucked into the column by vacuum
VC	Vacuum column	Water and gases boil out of the oil in the column
MV5	Disk gate	Vacuum system stop valve
OT	Oil trap	Foam or oil mist trap
MV6	Disk gate	Vacuum to transformer valve
MV7	Ball valve	Vacuum system stop valve
MV8	Ball valve	Drain oil from oil trap
V7	Electromagnetic valve	Air inlet into vacuum system in emergencies and to reduce foaming
VG1	Vacuum sensor	Indicates vacuum pressure, locks booster pump operation if vacuum not sufficient
LS4	Oil level sensor	Shows oil level in trap. Stop the unit if the level of oil in the trap exceeds acceptable level.
VP1	Backing pump	Creates vacuum to 30 mbar
VP2	Roots pump	Creates vacuum to 1 mbar
FL	Foaming sensor	When foam appears in the vacuum column, this sensor commands air inlet valve open
SL2	Liquid level sensor	Stops oil input pump if the oil level exceeds limit
SL3	Liquid level sensor	Stop oil output pump if the oil level falls below limit
MV9	Ball valve	Drains oil from vacuum column
P2	Centrifugal pump	Drains oil from the vacuum column and supplies it to the unit’s outlet
MV10	Ball valve	Vacuum column oil level control system adjustment valve
MV11	Ball valve	Vacuum column oil level control system adjustment valve
MF2	Mesh filter	Protects oil level control system from contamination.
G4	Pressure and vacuum sensor	Indicates pressure in oil level control system
V8	Angle valve	Prevents oil from being sucked into the vacuum column by vacuum. Controls oil level in the vacuum column
V9	Automatic ball valve	Bypass line valve. Lets the oil bypass the vacuum column in heating and filtration mode
G5	Pressure sensor	Indicates pressure at coarse filter inlet
F2	Fine filter	Stops particles larger than 25 micron
AV2	Air release valve	Removes air from filter
MV12	Ball valve	Drains oil from fine filter
G6	Pressure sensor	Indicates pressure at coarse filter outlet
SV2	Ball valve	Incoming oil sampling valve
V10	Automatic ball valve	Stops oil output from the unit.
V11	Automatic ball valve	Oil circulation valve
MV 13 ; MV 13.1	Ball valves	Stop oil input to the unit.
LP1	Leak collector	Leak collector/tray to contain spills in emergency situations
LS5	Oil level sensor	Stop the unit if an oil spill is detected
BV1	Return valve	Prevents air from being sucked into the F1 filter by vacuum
BV2	Return valve	Prevents air from being sucked into the F2 filter by vacuum
MV14	Ball valve	Tray oil drain valve
MV15	Ball valve	Buffer tank filling line stopping valve
V12	Electromagnetic automatic valve	Send oil to buffer tank

Regeneration section flow diagram

Regeneration section components

Position	Item	Description
V13	Automatic ball valve	Stops oil flow in sorbent reactivation mode
AV3	Air release valve	Removes air from pipeline
G7	Pressure sensor	Adjust vacuum system capacity during sorbent reactivation
V14	Automatic ball valve	Opens air flow to the column during reactivation
AF	Air filter	Purifies air entering the columns during reactivation
С1-С6	Sorbent column	Transformer oil regeneration column
ТС1-ТС15	Thermistor	Indicates temperatures during sorbent reactivation
DP	Intermediary tank	In this vessel air bubbles are separated during oil regeneration, and condensate formed during reactivation is collected and discharged
MV15	Ball valve	Oil drain from drain tank
LS6	Level sensor	Indicates oil presence in the bottom of intermediate tank.
LS7	Level sensor	Indicates oil presence at the top of the intermediate tank
G8	Pressure sensor	Indicates pressure in the intermediate tank
F3	Intermediary filter	Stops particulate matter after oil regeneration
AV4	Air discharge vavle	Removes air from fine filter
MV26	Ball valve	Drains oil from spill tray
G10	Pressure sensor	Indicates filter contamination
V15	Automatic ball valve	Stops vacuum line during oil regeneration
MT	Condenser	Condenses moisture and heavy fractions during sorbent reactivation
MV16	Ball valve	Drains condensate from the condenser
LS8	Level sensor	Indicates level limit in the condenser
V16	Automatic ball valve	Stops vacuum line during oil regeneration
G9	Pressure sensor	Adjust vacuum system operation during sorbent reactivation
MV17	Ball valve	Lets air into the vacuum system
VP3	Vacuum pump	Creates air flow required for sorbent reactivation
SR	Noise suppressor	Reduces noise at the outlet of the vacuum system
MV18	Ball valve	Drains moisture from the noise suppressor SR
MV19	Ball valve	Vacuum system exhaust valve. Used for direct exhaust bypassing charcoal filter CF.
MV21	Ball valve	Disconnects charcoal filter CF from exhaust line
MV22	Ball valve	Drains condensate from charcoal filter СF
CF	Charcoal filter	Purifies exhaust during sorbent reactivation
P3	Screw pump	Pumps condensate from the exhaust line
SF1	Safety valve	Prevents the body of pump P3 from overpressure
BV3	Return valve	Prevents oil from being sucked into the intermediary tank DP
V17	Automatic ball valve	Pumps reactivation waste and corrosive sulfur into buffer tank BT
BT	Buffer tank	Oil tank. Used for adding oil to the unit and collection of condensate.
LS9	Level sensor	Limits oil level in the buffer tank.
V18	Automatic ball valve	Pumps oil into buffer tank BT
V19	Automatic ball valve	Supplies oil from the buffer tank BT
MV23	Ball valve	Drains condensate from settling tank
MV24	Ball valve	Drain from buffer tank
MV25	Ball valve	Drain from buffer tank
P4	Centrifugal pump	Lets oil out of buffer tank BT and refills the unit with oil
FS2	Flow relay	Registers oil flow during refilling of the unit with oil.
LP2	Spill collector	Tray to collect oil spills in emergencies
LS10	Oil level sensor	Stop the unit of an oil spill is detected
BV4	Return valve	Stops air from being sucked into the line by vacuum
BV5	Return valve	Stops air from being sucked into filter F3 by vacuum
MV27	Ball valve	Spill tray drain valve

Flow diagram of transformer oil level control system TSS (Transformer Security System)

Oil level control system components

Position	Item	Description
V21	Electromagnetic valve	The valve prevents oil spills from the transformer in emergencies
MV27	Ball valve	Redirects oil flow during operation
MV28	Ball valve	Redirects oil flow during operation
MV29	Ball valve	Redirects oil flow during operation
MV30	Ball valve	Redirects oil flow during operation
MV31	Ball valve	Redirects oil flow during operation
V22	Electromagnetic valve	The valve prevents oil spills from the transformer in emergencies
V4	Air discharge valve	Removes air from pipelines