BRIEF DESCRIPTION OF CAPTIVE POWER PLANT PROCESS
The Captive Power Plant has been installed in KRIBHCO for the purpose of meeting the Electrical Power & High Pressure Steam Requirement of the KRIBHCO Fertilizer Complex. In other words, the consistent fertilizer production needs uninterrupted , reliable Electrical Power & High Pressure Steam for running the different equipments / Exchangers/ vessels of the Fertilizer complex. So. It is basically a co-generation type Thermal Captive Power Plant.
Steam Generation Plant
It has 3 Nos. of boilers producing High Pressure steam . Each boiler is designed to produce 275 t/hr of steam at 105 kg/cm2 absolute & at 510 deg C. The high pressure steam is required for steam turbine drives for Electric Power Generation , Pumps , Compressors of Process Plants & for other heat exchangers. Boilers were supplied and commissioned by M/S Foster Wheeler Power Products, UK Ltd. Normally two boilers will be in service and the third boiler will be either under shut down for maintenance /inspection work or kept under standby condition.
Though the two running boilers are capable of producing maximum of 550 t/hr of steam, at normal running conditions of KRIBHCO Fertilizer complex, the steam generation rate will be around 390 t/hr only. Hence the boilers will be generating about 195 t/hr each.
The normal steam distribution pattern will be as below:-
1. Steam for TG#1 ( for generation of 12 mw):- 60 t/hr.
2. Steam for TG#1 ( for generation of 12 mw):- 60 t/hr.
3. Steam for Boiler Feed Pump turbines: 10 t/hr
4. Total for Power Plant: 130 t/hr.
5. Total Steam For Process Plants.: 260 t/hr.
Grand Total: 390 t/hr
The basic utilities required/provided for steam generation are :-
a) Treated Boiler Feed Water to be supplied to boilers at suitable pressure & temperature as per requirement.
b) Fuel as the basic source of energy to be supplied to boilers which is burnt in burners as per requirement. The fuel can be either or combination of both as mentioned below depending on the availability.
i) Naphtha / NGL. ii) Natural Gas
c) Draft System – ie. For providing the air required for combustion of fuel in burners ( through FD fans) and withdrawal & disposal of products of combustion to the atmosphere through stack ( through ID fans).
d) Electric Power required for driving auxiliary equipments.
e) Cooling water required for Heat Exchangers.
f) Instrument air required for use in different instruments & control valves.
The steam generated from the running boilers is fed to a common steam header from where it is sent to consuming points by different steam pipe lines.
The steam is utilized
a) In Power Plant for generation Electric Power by Steam Turbine Generators and the auxiliary equipments and feed water heat exchangers. About 33 % of steam generated is utilized in Power plant.
b) In Process Plants for use in different heat exchangers/vessels & drives for the production of urea . About 67 % of steam generated is utilized in Process Plant ( Urea plant).
TG#1- TURBOGENERATOR NO.1
TG#2- TURBOGENERATOR NO.2
PRDS- PRESSURE REDUCING DE-SUPERHEATING STATION
BFP- BOILER FEED WATER PUMP
A Flow chart of the plant process is given below:-
Urea Turbine Condensate Heater drip LP steam
DM WATER TG CONDENSATE Vent
Technical Data of Boiler & Auxiliaries
No of Boilers installed
No of boilers in Service, normally
M/s Foster Wheeler Power Products Ltd, U.K.
Type of Boiler
High pressure, Water tube , Single Drum, Radiant , Front fired type.
Designed Steam Generation Rate of each boiler
Normal Steam Generation rate of each boiler
Rated steam Pressure
105 kg/cm2 absolute