What is the purpose of overfire air?

Overfire Air (OFA) systems divert a portion of the combustion air away from the primary combustion zone. Our CCA Combustion Systems brand Overfire Air system, deeply stages combustion for enhanced nitrogen oxide (NOx) reduction.

What is overfire air in boiler?

Over-Fire Air means an in-boiler staged combustion control at Hickok which limits the amount of combustion air introduced into the burner zone theoretically required to burn all of the fuel.

What is separated overfire air SOFA?

Advanced OFA systems such as separated overfire air (SOFA), where the overfire air is introduced some distance above the burners, and close-coupled overfire air (CCOFA), where the overfire air nozzles are immediately above the burners, can achieve higher NO.

What is OFA in boiler?

Abstract: The use of separated overfire air (SOFA) has become a standard technique of air staging for NOx reduction in the coal-fired boiler and can also be applied to existing boilers by retrofit.

What is advantage of using flue gas inside a boiler?

What is the advantage of using flue gas inside a boiler? Explanation: Using flue gas to heat up the water tubes reduces the greenhouse effect indirectly by making use of its heat to turn the water in water tubes into steam. This will be used in steam power plant to rotate the turbine and to produce electricity.

In what form is the coal used in boiler?

Explanation: The coal used for boiler is in powder form, in order to increase thermal efficiency. The different types of coal used in boiler are generally bituminous coal, brown coal and peat. Commonly bituminous coal is most preferred boiler fuel since it has volatile matter from 8 to 33% and ash content of 5 to 16 %.

What causes NOx in a boiler?

NOx emissions from boilers are influenced by many factors. The most significant factors are flame temperature and the amount of nitrogen in the fuel. Other factors affecting NOx formation are excess air level and combustion air temperature. Fuel containing more nitrogen results in higher levels of NOx emissions.

What happens if boiler pressure is to high?

If the boiler pressure is too high, there’s an increased chance of leaks developing in the system. But if boiler pressure is too low, the system won’t work as well. So keeping the correct boiler pressure is important to make sure that your system heats your home efficiently.

How long are couches supposed to last?

between 7 and 15 years
Sofas: Consider replacing your sofa before the seats start sagging to the point of not supporting you, the fabric has become stained and worn, and the frame is breaking down or squeaking. How long should a couch last? On average, a typical sofa lasts between 7 and 15 years.

Can couches be taken apart?

Break down the old, unwanted sofa you can’t sell Whether you want to throw it out without having to rent a dumpster or you can’t get it to physically fit through the door, it’s possible to take it apart yourself. This way, once it’s broken down into smaller pieces you can move it or throw it away with ease.

What is BOE in boiler?

BOE (Boiler Operation Engineer) is the most important examination now these days who worked in the power industry or other types of process industry. A candidate in order to be qualified for BOE (Boiler Operation Engineer) certificate of proficiency under these rules.