In many branches of industry, it is necessary to reach high temperatures
for production processes. The heat energy required for these processes
is transmitted by steam
However, due to the temperature needed for the
processes, the increase in the boiling point of the water and the high pressure
required, the investment and operating costs of the steam boilers increase
and a safe operation becomes difficult. Hot oil boilers are used to meet the
heat energy need effectively and safely at temperatures above 300°C.
The pressure in the system is the pump pressure that will overcome the
resistance in the infrastructure. Although the heat transfer oil is heated to
300°C, it can be used under atmospheric pressure because it is below
the boiling point. Thermal oil does not leave residues in the infrastructure,
corrode or freeze in normal climates. Besides that, no purification is needed
and temperature management can be done perfectly with automatic control
valves.
Due to the operating temperatures of the hot oil boiler, the flue gas
temperature is higher than those in its steam counterpart. However, if losses
associated with condensate, blowdown, flash steam and feed water are
considered in the steam system, the efficiencies of both hot oil and steam
boilers are comparable.
It is possible to increase the efficiency of the boiler by adding an economizer
or an air heater to the chimney for heat recovery. In addition, the need for
steam in the process can be met with hot oil heat exchangers.
Heating surfaces of hot oil boilers are manufactured from nested spirally
bent boiler pipes in accordance with EN 10216-2. Thanks to this serpentine
design, there is no stagnant point in the hot oil circulation.
