POWER PLANT QUESTION AND ANSWERS PART-18

1.      What is the average heat value of Fuel Oil and Gas?

10,000 Kcal/Kg, 10,000 Kcal/KNM3

2.      What are the combustible elements in fuels?

Carbon and Hydro carbons ( CHn)

3.      What element in the fuel is harmful to metal?

Sulphur

4.      What are the products of the complete combustion of Carbon,

                  Hydrozen and Sulfur?

CO2, H2O and SO2

5.      What are the products of incomplete combustion of Carbon, 

                   and Sulfur?

CO and SO are the products of incomplete combustion.

6.      What are the terminology used in firing fuels?

Atomizing, secondary air, pulverized fuel, etc. are some of the terminology used in firing fuel.

7.      How does pulverized fuel burned in the furnace?

Pulverized coal is one that ground to fine powder before being fed into the furnace.

Pulverized fuel is carried by air and sprayed through burner/nozzle into furnace. The fuel is ignited by any other flame, Igniter/oil burner in the beginning. The furnace temperature shall be raised about 250 Deg.C before admitting Pulverized coal (PC).

The primary air, secondary air and tertiary air shall be adjusted to make the ignition at 200 to 300 mm from burner. Secondary air is spined to provide mixing and to increase the stay time of the fuel in the flame zone.

8.      Explain Flash point and the grades of oil?

Flash point is applicable for fuel oil. Fuel oil will easily get ignited at a higher temperature. This condition is known as Flash Point for the fuel oil.

Diesel oil, Bunker –C oil, Low sulphur High stroke oil, etc. are some grade of fuel oil fued in boiler.

9.      Is fire point important?

The temperature,  at which oil start firing, is firing point. It is important to burn a fuel.

10.   Why do plant operators know about pour point of their oil?

The pour point is the temperature of the fuel will start flow when it is pumped. The fuel in the pipe shall be kept at a temperature above pour point by heat tracing provided for the pipes, fittings and the pumps. Operator shall adjust the set point depending on the pour point of the fuel. When fuel oil is imported from different countries, the same will vary consignment to consignment.

Continue in part-19...