greater noida institute of technology

GREATER NOIDA INSTITUTE OF TECHNOLOGY

DEPARTMENT OF MECHANICAL ENGG.

SEMINAR PRESENTATION

ON

BOILER

(BABCOCK & WILCOX BOILER)

Submitted To: Submitted By:

Mr. Syed Qaiser Husain Raju singh

CONTENT

Introduction

Classification

Babcock & Wilcox Boiler

Construction Of B&W Boiler

Working

Features

Accessories

Advantages & Disadvantages

Applications

INTRODUCTION A water containing vessel in which

water is heated under pressure Transfer heat from a fuel source (oil,

gas, coal) into steam The steam or hot fluid circulates out of

the boiler for use in various process or heating appliances.

Classification

Fire tube & water tube boiler

Babcock & Wilcox boiler

The evaporative capacity of this boiler is high compared with

other boilers (20,000 to 40,000 kg/hr). The operating pressure

lies between 11.5 to 17.5 bar.

The draught loss is minimum compared with other boilers.

The defective tubes can be replaced easily.

The entire boiler rests over an iron structure, independent of

brick work, so that the boiler may expand or contract freely.

The brick walls which form the surroundings of the boiler are

only to enclose the furnace and the hot gases.

Construction of B&W boiler

Steam and water drum ( boiler shell )

Water tubes

Uptake header and down corner

Grate

Furnace

Baffles

Super heaters

Mud box

Inspection door

damper

Working of Babcock and Wilcox boiler

Coal is feed to grate through the fire door and is burnt.

Flow of flue gases

Water circulation

A damper is fitted as shown to regulate the flue gas outlet and hence the draught

features of Babcock and Wilcox Boiler

efficiency is higher defective tubes can be replaced easily components are accessible for inspection

even during the operation draught loss is minimum Steam generation capacity and operating

pressure are high The water tubes are kept inclined at an angle

of 10 to 15 degree to promote water circulation

Accessories

Safety valve

Water level indicators

Bottom blowdown valve

Continuous blowdown valve

Flash tank

Automatic blowdown/continuous heat recovery system

Low water cut off

Steam drum internals

Surface blowdown line

Circulating pump

Feed water check valve or clack valve

Chemical injection line

Desuperheater tubes or bundles

Hand holes

Advantages

Steam can be generated at very high pressures

Heating surface is more Steam can be raised more quickly maximum amount of heat is transferred to

water A good and rapid circulation of water can

be made it is easier to transport It is suitable for use in steam power plants

Disadvantages

It is less suitable for impure and sedimentary water, as a small deposit of scale may cause the overheating and bursting of tubes. Hence, water treatment is very essential for water tube boilers.

Maintenance cost is high. Failure in feed water supply even for a short

period is liable to make the boiler overheated. Hence the water level must be watched very carefully during operation of a water tube boiler.

Applications

Stationary Marine Railways Variety of process applications in industries Chemical processing divisions Pulp and Paper manufacturing plants Refining units

THE END