Introduction of FOHS
The Fuel oil handling system (FOHS) shall broadly comprise of the following:
- Heavy fuel oil (HFO) / Low Sulphur heavy stock (LSHS) system for start-up of the boiler, load carrying up to 30% BMCR and as secondary fuel for pulverized coal flame stabilization at start-up / low load operation.
- LDO (Light Diesel Oil) system for initial start-up (cold start-up), warm-up, low load operation up to 7.5% BMCR and for flushing of HFO pipe lines.
BMCR: Boiler Maximum Continuous Rating (BMCR) is the maximum rating specified for the boiler.
Function of Fuel Oil Handling System
The purposes of the Fuel Oil Handling System are targeted to achieve the following:
- HFO/LSHS unloading from railway wagons
- LDO unloading from railway wagons
- Storage of HFO/LSHS
- Storage of LDO
- Collection of pipes drain oil emanating from Equipment, Strainers etc. to Drain Oil Tank located in Fuel Oil Pump House and recycle back to HFO/LSHS Tanks.
- Collection of open drains from unloading area, tank farm, Fuel Oil pump house (FOPH) to oily water sump (OWS) for further treatment, recovered oil from OWS send back to drain oil tank through gravity.
- Pressurizing and heating of HFO/LSHS for supply to boiler Fuel Oil burner at required pressure temperature condition and return to HFO/LSHS tanks.
- Pressurizing of LDO for supply to boiler Fuel Oil burner and return to LDO tanks.
- Heating of entire HFO/LSHS system including HFO/LSHS wagons, storage tanks, pipe lines etc. to ensure HFO/LSHS flowability.
Fuel Oil Handling System (FOHS) Description
Fuel Oil Handling System is described as following sub-systems:
- HFO/LSHS Unloading system
- LDO unloading system
- Fuel Oil Storage System
- HFO heating and Pressurizing System
- LDO pressurizing system
- Steam and Condensate System
- Drain Oil System
- Return HFO Cooling System
Note: Each sub-system description includes its own specific design requirements and basis.
Fuel Oil Handling System (FOHS) Components
The major components of the fuel oil handling system are as follows:
- Pumps (Pressurizing Pumps, Unloading Pumps, Oil water Sump Pumps, DOT Pumps)
- Storage Tank
- Strainers (Basket Strainer, Duplex Strainer)
- Heaters & Cooler
- Pipes (Fuel oil pipes, Water pipes, Air pipes)
- Valves (Gate valves, Globe valves, Check valves, Ball valves, Motorized Operating Valve (MOV), Control Valves etc.)
- Instruments (Pressure Gauge, Pressure Transmitter, Pressure Switch, Temperature Gauge, Temperature Transmitter, Flow meter, Differential Pressure Gauge, Differential Pressure Transmitter etc.)