COMBUSTION IN A BOILER FURNACE

PROCESS:  a mixture of fuel and air are burned inside the combustion zone, in a boiler or a furnace. It is not easy to properly mix the fuel and air, inside the chamber. So to ensure that every fuel molecule will find sufficient oxygen to combine with, and form carbon dioxide, an excess or extra of air is admitted along with the fuel.

This excess air has a simple objective, it has to make itself available for the fuel molecules, to combine. It does not take part in the reaction. After every single fuel molecule is burned, whatever excess air was given in the beginning, comes out thru the stack, along with the other flue gases.

The oxygen concentration in this air is measured, and it tells us whether the combustion is complete and has been efficient. Less than adequate oxygen, measured in the stack,  tells us that the fuel  doesn’t get sufficient oxygen, and so some of the fuel is left unburnt, and maybe CO is also produced. Combustion Analysis System.

More than adequate oxygen tells us that whatever heat is produced in the chamber, is taken away by the extra air that is given along with the fuel. This heat loss also means inefficient combustion in a way.

MEASUREMENT:  for this application , it is always O2, CO, and CO2 that are monitored. O2 tells us the type of combustion. The CO levels tell us how much fine tuning is required for the air to fuel ratio.

SOLUTION: for this application, for all small boilers, testo310, 320 and 330-LL can be offered. And for large power plants, and bigger boilers and furnaces, 340, and 350 are the right solutions. Ofcourse with O2 and CO sensor, and CO2 is always calculated.