economizer heat exchanger -hot water boilers

[nicolai]

Hi folks
is it viable to provide an economizer heat exchanger for preheating on the stack outlet of high temperature hot water boiler ( fire tube) - LFO fired?

is their any pitfalls to be aware of using an economizer on an LFO fire tube boiler?

many thanks

 

[MJCronin]

There are companies that can help you size/evaluate a waste heat economizer for your boiler.
.
Although you probably have a low sulfer fuel, you shoul evealuate if the new configuration would cause "cold end corrosion" furthermore you may want to consider what the new economizer would do to the draft of your system.

Your boiler performance could suffer from insuficient draft.

What is your flue gas exit temperature ? ...About 200-225F may be as low as you can go

What is the massflow of your boiler blower ?

What is the pressure supplied by feedwater supply to the boiler ? ... Can your boiler operate well with a reduced pressure ?

These HXs tend to be fairly heavy and good sized and mounted in the ductwork where the flow goes vertical ... Do you have room ?

My first phone call would be to the Boiler vendor ....

MJCronin
Sr. Process Engineer

 

[Dhurjati Sen]

Economizer - No

Condensate Preheater - Yes
which is quite a general practice.

Rest as per MJ Sir.

DHURJATI SEN
Kolkata, India