Difference Between Smoke tube boilers and Water tube boilers Sr. No. Smoke tube boilers Water tube boilers 1. In this the hot flue gases flow in the tubes surrounded outside by the water. In this the water flows in the tubes surrounded outside by the hot gases. 2. These boilers have large water to steam … Read more

Babcok Wilcox Boiler This is one of the most important type of a water tube boiler generally employed in the power houses for power generation as shown in Figure. It consists of number of inclined water tubes (WT) connected between the uptake header (UH) and the downtake heater (DH). Headers are provided with hand holes … Read more

Smoke Tube Boilers Q. Smoke Tube Boilers or cochron boiler diagram. In these boilers the flue gases pass through the tubes which are surrounded by water in boiler shell. Some of the boilers of these type are being discussed below. Cochron Boiler : It is a fire tube boiler in which the flue gases from the … Read more

Classification of Boilers The boilers may be classified mainly as follows : Depending upon the relative position of water and flue gases : Smoke tube or fire tube boilers : In these type of boilers the hot gases or the flue gases from the furnace are passed through the tubes surrounded by the water outside … Read more

Introduction to Steam Generators or Boilers The requirement of steam as a working substance is either for power generation or for process and space heating in industrial applications. Steam generator or a boiler as per Indian boiler act 1923 is a closed pressure vessel used for generation of steam under pressure. A boiler is usually … Read more

Two Types of Air Preheater The temperature of gases leaving the economizer after heating the feed water is in the range of 250°C- 450°C. This heat energy in exhaust gases can be further utilized to preheat the surrounding air before supplied to combustion chamber. After transfer of heat to air, these gases are finally discharged … Read more

 Superheaters The superheater is a heat exchanger whose function is to superheat the wet or saturated steam upto desired temperature by transfer of heat energy. The superheaters are either located in the passage of hot flue gases or directly over the furnace depending upon its design and application. In modern steam power plants, the superheating … Read more

Fluidized Bed Combustion Boilers (FBCB) Figure A Minimum fluidization velocity of air was defined the velocity of air needed at which the mixture of fuel and air starts behaving like a fluid and the burning of the fuel in such state was called fluidized bed combustion boilers. We shall now discuss the classification and working … Read more

Economisers An economizer is an heat exchanger which is used to raise the temperature of feed water with the help of waste heat energy of gases before it is supplied to the boiler. Note that the temperature of gases is about 350°C 550°C at exit of last heater/ superheater having large amount of heat energy … Read more

Methods of Superheat Temperature Control For proper and efficient operation of power plant it is essential to control the temperature of steam according to load on the power plant. The reduction of about 20°C temperature of superheated steam causes the increase in 1% heat rate (H.R.) [H.R.-Work output x 3600 Efficiency (kJ / kWh) my] … Read more