Alfa Laval FOCUS
Alfa Laval Fuel Oil Cleaning Unit Solutions (FOCUS) are automated modular systems for the purification of liquid fuel oils. The fuel cleaning process is designed to overcome the harmful effects of fuel oil contaminants, primarily the trace metals sodium and potassium, as well as water and solid particles.
Application
High temperature corrosion, ash deposition and the clogging and erosion of fuel systems are costly operating problems attributed to fuel contaminants. Liquid fuels vary substantially in physical properties and level of contaminants, but with correct treatment a wide range of liquid fuels can be used effectively in any modern gas turbine power plant.
Features and Benefits
- Enable full compliance with current standards of fuel quality at the turbine inlet
- Constant efficiency and highest separation efficiency of water and solids ensured
- Proven, reliable operation
- No pre-filtration necessary
- Environmentally friendly sludge disposal (no filter cartridges)
- Automatic, unattended operation
- Comparatively low operating cost
- Simple, compact and robust design
Process description
The FOCUS module will pump untreated fuel oil with centrifugal pumps via
suction strainers to the separators. The centrifugal separator is the heart of the cleaning unit and provides a reliable and consistent method for the removal of solids and water simultaneously from fuel oils.
Untreated fuel oil is fed continuously through the separator, where any water and solids are separated from the fuel oil by the action of centrifugal force.
Separation takes place in a rotating bowl. When the water seal has been established, the feed is introduced to the bowl inlet. The inlet is equipped with circular discs, the Optiflow inlet, which accelerates the feed before it enters the bowl disc stack.
The oil is forced towards the centre of the bowl through the disc stack. A built-in paring disc pump discharges cleaned oil continuously.
Separated water rises along the outside of the disc stack and is continuously discharged
by a paring disc in the water outlet. Separated sludge and solid particles accumulate at the periphery of the bowl and are discharged periodically before they build-up to a point where they would interfere with the separation process.
The discharge cycle is initiated at the control panel by either pushbutton or automatically by the electronic program control system on completion of a set time cycle. Water and sludge removed by the centrifugal separators collect in the centrifuge sludge tank and are pumped to the customer’s waste treatment system by a pneumatic sludge pump controlled by level switches.
An oil and water monitor in the purified fuel oil discharge line checks the quality of the purified oil leaving the centrifugal separators. The system is specifically designed for accurate determination of the amount of water in the oil stream. During process alarm conditions, the divert valve switches the flow of the purified oil away from the day tank to the raw fuel storage tank.
The fuel oil cleaning unit is controlled, monitored, and supervised from a centralized control console. A state-of-the-art PLC-based control panel provide monitoring and control functions necessary for operation of the system.
The fuel oil treatment plant
As an important component in your fuel oil treatment plant, the cleaning unit prepares the fuel prior to being forwarded to the gas turbine. By ensuring consistent compliance with specific fuel oil purification requirements, your cleaning unit will contribute to a longer turbine service life and to a reduction in operating costs through less maintenance and downtime.
Optional equipment
- Ex-proof execution of unit
- Junction box for remote mounting of control panel
- Remote system start / stop
- Remote mounting of feed pump
- Water washing system
- Demulsifier dosing system
- Oil feed preheater
- Water monitor in purified oil outlet
- Containerized solution