Alfa Laval Aalborg HPNC Boiler

Steam supply for deodorization and physical refining

of oils and fats

The Alfa Laval Aalborg High Pressure Natural Circulation

(HPNC) steam boiler is a high performance boiler devel

oped to comply with the rigorous specifications of the food

and vegetable oil industry, by ensuring high quality and

reliability throughout the plant life time.

Application

The HPNC boiler is specially designed for the deodorizing

process in the physical refining of vegetable oils and fats. The

boiler provides steam at high pressure and temperature to

ensure an efficient deodorizing process.

The boiler operates efficiently as an integrated unit of any

refining process plant for vegetable oils or fats.

The boiler can also be supplied as a stand alone unit or as

replacement of existing steam boiler or thermal fluid heater.

Design features and benefits

The HPNC boiler is supplied in 9 different standard sizes, with

steam effect ranging from 125 to 2.500 kW. The standard boiler

is designed to operate at steam pressures up to 90 barg.

The boiler’s robust coil type design (see illustration page 2)

is based on thermal fluid heaters, which ensure:

• Flexibility in absorbing thermal expansions, a feature that

will ensure low stress levels in the boiler tubes and thereby

also long life time

• Efficient heat transfer as gas flow is perpendicular to tube

direction creating turbulence

• Efficient cooling of tube sections

• Verified pressure loss calculations (water/steam flow) that

provide assurance of cooling and no overheating

Highest possible efficiency is ensured through a compact

design, and reliable operation is guaranteed by using high

quality instrumentation.

Only high pressure grade steel tubes are used to ensure

high reliability.

Working principles

The Alfa Laval Aalborg HPNC boiler is designed to operate

in a closed loop system, a so called thermo syphon system,

where circulation is ensured through gravity. The steam cycle

is completely sealed off to remove any risk of corrosion.

Steam generation is taking place in two concentrically

arranged coils – the inner coil which forms the furnace and

the outer coil which provides for convective heat transfer

through the second and third gas passes.

Depending on boiler size each coil can consist of one single

flow way or several parallel flow ways. This design ensures

sufficient and reliable circulation and thereby also cooling of

all the heat transfer parts of the boiler.

Standard equipment

As a standard the high pressure boiler is fitted with the required

accessories for a safe and reliable operation, including safety

valve, rupture disc assembly and low water level cut-off

electrodes.

Burner equipment includes pressure jet burner for fuel oil, gas

or a combination hereof as well as the required equipment for

fuel line system.

The boiler system can be filled with water using a vacuum

system or by using the optional high pressure filling pump.

Optional extras

• Heavy fuel oil burner

• Air pre-heater

•  Sparging steam super heater for low cost heat recovery

without electrical power consumption

•  PLC based control system

•  Filling system (pump and ancillaries)