The boiler generates steam at ________.

The correct answer is option 3):(high pressure and high temperature)

Concept:

The higher the pressure of a boiler the more heat must be applied to make steam. With the increased pressure,  in turn get steam at higher temperatures. Higher temperature steam contains more energy per pound, which is known as Enthalpy.

Steam power plants are widely utilized throughout the world for electricity generation, and coal is often used to fuel these plants. ​A steam power plant consists of a boiler, steam turbine and generator, and other auxiliaries.

The boiler generates steam at high pressure and high temperature. The steam turbine converts the heat energy of steam into mechanical energy as in fig

 Additional Information

Fire Tube boiler:

In this boiler, the hot flue gases are present inside the tubes and water surrounds them and sometimes around the outside of the tubes. Hence we can say that they are internally as well as externally fired boilers. They are low-pressure boilers. The operating pressure is about 25 bar. Externally fired fire tube boilers are locomotive type boilers, horizontal return tubular (HRT) boiler, etc. Internally fired fire tube boilers are Scotch-marine boilers, Cochran boiler, package boilers, etc.

Water Tube Boiler:

In this boiler, the water is present inside the tubes and the hot flue gases surround them. They are high-pressure boilers and the operating pressure is about 250 bar. Water-tube boilers are always externally fired. Stirling Boiler, La-Mont Boiler, Benson Boiler, Yarrow Boiler, Babcock and Wilcox Boilers are water tube boilers