A PRESENTATION ON

BOILERBY:Arpit Modh (16BCH035)B.Tech ChemicalNirma University,Ahmedabad.

BOILER Boiler is an apparatus to produce steam. Thermal energy released by combustion of fuel issued to

make steam at the desired temperature and pressure.

The steam produced is used for:1. For generating power in steam engines or steam

turbines.2. Heating the residential and industrial buildings.3. Performing certain processes in the sugar mills,

chemical and textile industries.

Selection of boiler:The working pressure & quality of steam.Steam generation.Floor area available.Accessibility for repair & inspection.Comparative initial cost.The fuel & water available.Operating & maintenance cost.

BOILER PROPERTIESa) Safety: The boiler should be safe under the operating conditions.

b) Accessibility: the various part of boiler should be accessible for repair & maintenance.

c) Capacity: Should be capable of supplying Steam according to the requirements.

d) Efficiency: Should be able to absorb a maximum amount of heat produced due to burning of fuel in the furnace.

e) It should be simple in construction.

f) Its initial cost and maintenance cost is low.

g) It should be capable of quick starting and loading.

CLASSIFICATION OF BOILERS

The boiler may be classified as :1. According to geometric orientation2. According to relative position of water and hot gases3. According to location of furnace4. According to method of water circulation5. According to working pressure6. According to mobility of boiler7. According to number of tubes in boiler

1. According to geometric orientation

If the axis of boiler is horizontal, the boiler is called horizontal. e.g. Lancashire boiler

If the axis is vertical then it is called vertical. e.g. Cochran boiler

If the axis is inclined then it is called inclined.

According to relative position of water and hot gases

In the fire tube boiler the hot gases are inside the tubes & the water surrounds in the tube. e.g.Cochran, Lancashire

In the water tube boiler the water is inside the tube & the hot gases are surround them. e.g. Babcock and Wilcox boiler

2.

1. FIRE TUBE BOILERS

2. WATER TUBE BOILERS

3. According to location of furnaceThe boiler is known as externally fired if the fire is

outside the shell. e.g. Babcock & Wilcox

In case of internally fired boilers, the furnace is located inside the boiler shell.

e.g. Cochran, Lancashire

4. According to method of water circulationIn forced circulation type of boilers the circulation of

water is done by forced pumps.

In natural circulation type of boiler the circulation of water in boiler takes place due to natural convention.

ex. Lancashire, Babcock and Wilcox

5. According to working pressureThe boilers which produce steam at pressure of 25 bar

and above are called high pressure boiler. e.g. Babcock and Wilcox

The boiler which produce steam at pressure between 10 to 25 bar are called medium pressure boiler. e.g. Lancashire

The boiler which produce steam at pressure between 3.5 to 10 bar are called low pressure boiler. e.g. Cochran

6. According to mobilityStationary boiler: The boiler cannot be transported

easily from one place to another place. e.g. Lancashire, Babcock and Wilcox

Mobile boiler: It is portable boiler and can be easily transported. e.g. Locomotive

7. According to number of tubes in the boilerSingle tube boiler: This boiler having only one fire or

water tube for circulation of water or hot gases. e.g. Cornish boiler

Multi tube boiler: This boiler having two or more fire or water tubes for the circulation of water or hot gases. e.g. Cochran, Lancashire, Babcock and Wilcox boiler