2014-10-10

Rules of Thumb-Boiler

An economizer that recovers 5% of boiler input.

A comprehensive tune-up with precision testing equipment to detect and correct excess air losses, smoking, unburned fuel losses, sooting and high stack temperatures can result in boiler fuel savings of 2% to 15%.

An upgraded boiler maintenance program including optimizing air-to-fuel ratio, burner maintenance, and tube cleaning, can save about 2% of a facility’s total energy use.

A 5 degree C Change in boiler exhaust temperature changes to save 1% to 2% of a boiler’s fuel use.

For every 11°F that the entering feed water temperature is increased, the boiler’s fuel use is reduced by 1%.

Effective boiler load management techniques, such as operating on high fire settings or installing smaller boilers, can save over 7% of a typical facility’s total energy use.

A 3% decrease in flue gas O2 typically produces boiler fuel savings of 2%.

Load management measures, including optimal matching of boiler size and boiler load, can save as much as 40% of a boiler’s fuel use.

Removing a 0.8 mm deposit on boiler heat transfer surfaces can decrease a Boiler’s fuel use by 2%; removal of a 3 mm deposit can decrease boiler fuel use by over 8%.

Boiler Blow Down - Range of 4 to 8 % of boiler makeup.

We can calculate the capacity of boiler through heating surface its a very simple for example a boiler having heating surface of = 132 sq meter applying thumb rule = 132/24=5.5 tons

The radiation and unaccounted losses could amount to between 1% and 2% of the gross calorific value of the fuel.

One kcal raises the temperature of one Kg of water one degree C
One kg Steam = 540 Kcal
1 kg water @ 5.4 degree C= 5.40 Kcal
5.4/540 = 1%