Mr.D.VISUVASAM, ADDITIONAL GENERAL MANAGER (REGD)/AQCS / BHEL delivered a
special lecture on “THERMAL POWER PLANT, POWER PLANT POLLUTION AND BOILER
INSRUMENTATION” at EIE Department on 18-03-2015.
explained as :
are basically three main units of a thermal power plant: 1. Steam Generator
or Boiler 2. Steam Turbine 3. Electric Generator
From Coal Basic Principle
Objectives of Instrumentation & Control Efficient Operation of the plant.
Economic Operation of the plant. Safe operation of the plant. Pollution
entire task is often taken up by control & instrumentation or simply
instrumentation system which has following functions:- a) Measurement b)
Control c) Operation d) Monitoring e) Protection
Analysis of (1) Water (2) Steam (3) Flue Gases And Others Expansion/
Contraction, Level, Flow, Temperature, Pressure Should be switched on
manually when a overall control system fails.
Delays should be as small as possible
Very accurate ŘQuantities
To Be Measured: For a Plant Measurement system needs to be:
Measurement Points & Variables
Turbine & Thermocouple generator
Expansion Elements Liquid columns: Low range pressure measurement May be of
U-Tube type or well-Type.
Measurement of Temperature; Temperature can be measured only by using
ULTRA VIOLET SENSOR This device is used in furnace and it measures the
intensity of ultra violet rays there and according to the wave generated
which directly indicates the temperature in the furnace.
Measurement of Flow: Dual function meters usually measure flow rate with
linear output & minimum error. Vortex & Ultrasonic meters have become
are two groups of measuring devices:- 1. POSITIVE, OR VOLUMETRIC, which
measure flow by transferring a measured quantity of fluid from the inlet to
the outlet. 2. INFERENTIAL, which measures the velocity of the flow and the
volume passed is inferred, it being equal to the velocity times the cross
sectional area of the flow. The inferential type is the most widely used.
Analysis of pH, DO,TURBIDITY
through the Central Control System (DDC-MIS) “Distributed Digital Control
Monitoring and Information System”.
in Control and Instrumentation Department of Thermal Plant Control and
Instrumentation Department have following labs: 1. Manometry Lab 2.
Protection and Interlocks Lab 3. Automation Lab 4. Electronics Lab 5. Water
Treatment Plant 6. Furnaces Safety Supervisory System Lab
Pollution Control systems: to control air and water pollution. 1.
Electrostatic Precipitators: The ash left behind after combustion of coal is
arrested in high efficiency Electrostatic Precipitators (ESP’s) 2. Flue Gas
Stacks: Tall Flue Gas Stacks have been provided for wide dispersion of the
gaseous emissions into the atmosphere. 3. Neutralisation Pits:
Neutralisation pits have been provided in the Water Treatment Plant (WTP)
for pH correction of the effluents before discharge into Effluent Treatment
Plant (ETP) for further treatment and use.