Aalborg HPNC
For supplying steam needed in deodorization processes and the physical refining of oils and fats.
The High Pressure Natural Circulation (HPNC) steam boiler is designed to provide the high-pressure and high-temperature steam essential for efficient deodorizing in the physical refining of vegetable oils and fats.
HPNC boilers are compact, high-performance units developed specifically to comply with the stringent specifications used in the food and vegetable oil industry.
Main features and key benefits of Alfa Laval HPNC boilers
- Full compliance with stringent food and vegetable oil industry specifications
- Compact, space-saving design for easy installation, or to replace existing steam boilers or thermal fluid heaters
- High-quality instrumentation to provide accurate operating data and ensure reliable operation
How it works
The coil-type design of High Pressure Natural Circulation (HPNC) steam boilers is based on the well-known principle of thermal fluid heaters.
HPNC boilers are designed as a closed-loop system (a so-called thermo syphon system) in which gravity drives the circulation process.
Two concentric coils are used to generate the steam. The inner coil forms the furnace and the outer coil provides convective heat transfer through the second and third gas passes. High-pressure grade steel tubes are used to ensure maximum reliability.
Depending on boiler size, each coil can consist of one single flow path or multiple parallel flow paths. This ensures satisfactory circulation with a high degree of reliability, as well as cooling all the heat transfer parts of the boiler.
The steam cycle is completely sealed off to eliminate any risk of corrosion.
Technical benefits
- Effective absorption of thermal expansions. This ensures low stress levels in the boiler tubes, resulting in a long service life
- Efficient heat transfer due to the turbulence that results from the flow of gas being perpendicular to tube direction
- Efficient cooling of the tube sections in the boiler
- Verified pressure loss calculations (water/steam flow) that make sure of effective cooling and help prevent overheating
Standard equipment
HPNC boilers are available in 9 standard sizes, with steam effects ranging from 125 to 2,500 kW. The standard boiler is designed to operate at steam pressures up 90 barg.
As a standard the HPNC boiler systems are fitted with all the ancillary equipment required for safe, reliable operation. This includes bursting disc, safety valve and cut-off electrodes to guard against low water levels and ensure circulation.
The burner equipment includes a pressure jet burner for fuel oil or gas (or any combination of these) as well as the equipment required for the fuel line system.
The boiler system can be filled with water using a vacuum system or by using a high-pressure filling pump (optional equipment).
Optional equipment
- Heavy fuel oil burner
- Air pre-heater
- High-pressure filling pump
- Sparging steam super heater for low-cost supply of steam to deodorizer unit saving electrical power