Admin Table of Contents
How do I find a leak in my APH?
For this 700-MW power plant firing bituminous coal, leakages are calculated by using information on static pressure differences between the PA, SA, and flue gas streams, assuming two-thirds of the leakage occurs at the hot end of the APH. The air to flue gas leakage is 12% (by weight).
What do you know about air preheating?
An air preheater is any device designed to heat air before another process (for example, combustion in a boiler With the primary objective of increasing the thermal efficiency of the process. They may be used alone or to replace a recuperative heat system or to replace a steam coil.
What is the location of air pre heater?
In Air Preheater (APH) heat from flue gases is absorbed for pre heating air in such a way that required stack temperature is achieved. Therefore, Air preheater of boiler is located between economizer and chimney.
How do you calculate coal fired boiler efficiency?
Direct efficiency In order to calculate boiler efficiency by this method, we divide the total energy output of a boiler by total energy input given to the boiler, multiplied by hundred. GCV= Gross calorific value of the fuel.
What is the function of air pre heater?
Air Pre-heaters are basically heat-exchangers installed in the exit flus gas duct of the boiler. The purpose of the air preheater is to recover the heat from the boiler flue gas which increases the thermal efficiency of the boiler by reducing the useful heat lost in the flue gas.
What does regenerative air preheater consists of?
Regenerative type of air preheater:- Regenerative type is dynamic and continuously keeps on rotating about vertical or horizontal axis. It consists of a circular diaphragm shaped construction, which is divided into several sectors. Each sector is stacked with several blocks of baskets, arranged in three tires.
What does a pre heater do?
The engine preheater is the device that preheats the engine at low temperatures in winter before starting. Protecting the engine and achieving the effect of hot starting. So its main function is to reduce the engine fuel viscosity, to avoid the engine wear and to lower the engine exhaust pollutant emissions.
How do I calculate the heat rate of my boiler?
Divide this heat gain by the length of time for which the boiler runs, measured in second. For example, if the boiler runs for 1,800 seconds, dividing 12,558,000 by 1,800 gives 6,977, or a little under 7,000. This is the heat input rate, measured in joules per second, or Watts.
What is the difference between economiser and air preheater?
1. economizer requires lesser space and surface area compared to the air heater due to the high tube side water heat transfer coefficient and larger U compared to the air heater. In addition,extended surfaces make them very compact. Air heaters have very low overall U and hence huge.
What are the advantages of air preheater?
Advantage of pre-heating the air: (1) It increases the temperature of the furnace gases, improves combustion rates and combustion efficiency. (2) Air preheater extracts heat from the flue gases, and lowers stack temperatures thus improving the overall efficiency of the boiler.