Supercritical boiler ntpc sipat

1SUBMITTED BY :-Pratik gupta

SupercriticalBoiler

Introduction

It is a thermal power plant of installed capacity: 2980 MW

Stage 1 = 3 X 660 MW Stage 2 = 2 X 500 MW

Production Inputs

Coal Source› Dipika Mines of South Eastern Coalfields

Limited Water Source

› Hasdeo barrage

How electricity is produced?

Water is heated, turns into steam and spins a steam turbine which drives an electrical generator. After it passes through the turbine, the steam is condensed in a condenser and recycled to where it was heated.

Boiler

The term boiler is used for a closed vessel in which water or other fluid is heated

A Boiler or steam generator essentially is a container into which water can be fed and steam can be taken out at desired pressure, temperature and flow.

What is supercritical?

“Supercritical” is the thermodynamic state where there is no clear distinction between the Water and Steam phase in the Ranking Cycle

Water reaches to steam state at a critical pressure above 22.1 MPa at 374 °C

What is supercritical?

At 22.1 Mpa and above, there is no physical differentiation between water and steam.

This "critical point" is at the apex of the saturation line on T-s coordinates.

Above this pressure, the physical properties (density, compressibility, and Viscosity) change continuously from those of a liquid to those of a vapor.

Super Critical – A Fourth State

Possess Goodness of both liquid and Gas …. 9

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Benefits of Supercritical Units Higher unit cycle efficiency (40 - 42%)

Lower heat rate and electricity generation cost is lower

Lower water losses because no continuous blow down

Reduced auxiliary power consumption

Environmental Benefits

Reduce carbon dioxide (CO2) emissions and provides carbon credit within the Rankine cycle

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Types of boilers

Drum type (Sipat Stage II 500MW)

Once-through type (Sipat Stage I 660MW)

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Drum type boiler

Steam generation takes place in furnace water walls

Fixed evaporation end point - the drum

Steam -water separation takes place in the drum

Separated water mixed with

incoming feed water

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Once -through flow through all

sections of boiler (economiser,

water walls & superheater)

Feed pump provides the

driving head

Suitable for sub critical &

super critical pressures

Once Through Boiler

conclusion

Super critical power plants are the effi cient plants to produce greater out put although it has some drawbacks ….

Thank You