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Why does vacuum in steam condenser reduce or drop??

  1-High exhaust temperature: Vacuum drops or maintains at lower side due to high exhaust steam temperature flow into steam condenser. This high exhaust temperature is mainly due to 1-Operation of Turbine at lower loads 2-More clearance in labyrinth seals 3-Not operating exhaust hood sprays 4-More load on condenser 5-Breaking of ejector U loop 2-Low circulating cooling water flow Vacuum in condenser reduces due to inadequate cooling water flow through steam condenser. This is mainly due to; 1-Problems associated with pumps 2-Air pockets in pipe line 3-Leakages in cooling water line 4-Stuck of discharge valve of pump 3-High cooling water temperature at condenser inlet Higher cooling water temperature at condenser inlet results into reduction of vacuum due to poor heat transfer from steam to water 4-Poor heat transfer in condenser Very less or poor heat transfer in steam condenser reduces vacuum to very low level resulting into high exhaust temperature &am

Introduction to power plant

A power plant also referred to as a power station and which generates power, it is an energy producing source and the final form of energy being converted is electrical energy. Power plant is one of the most vital sectors for any country or industry. In this competitive world nothing will move without the  electric power, be it an industry, home, office etc.So such an important sector needs to be operated and maintained very dexterously, efficiently and safely.
Based on the primary source of energy power plant are of following types;
Wind power plants: Primary source of energy is natural wind, the speed of win is being utilized to produce electric energy.
Solar power plants: Primary energy is the energy received from the sun that again is converted into electric energy.
Hydal power plant: As the name indicates primary source of the energy is Hydro-water
Tidal power plant: Energy present in the tides is utilized for producing the electric energy
Geothermal power plant: Geothermal power plants use hydrothermal resources that have both water (hydro) and heat (thermal). Such type of  plants require  Hydrothermal resources having high-temperature that come from  dry steam wells or from hot water wells.
Thermal power plants: Primary source of the energy is fuel, where energy from the various fuel on oxidation is converted into heat energy, further, this heat energy is converted into high pressure and temperature thermal energy (Steam).This steam is made to fed in steam turbines where the thermal energy present in the steam is converted into kinetic energy in Turbine finally kinetic energy is converted into electric energy in Turbo generators.
Thermal power plants may be captive power plants, cogeneration plants and large power plants.
Power sector is matured sector and the plants are designed meticulously addressing the prior challenges faced. Ultimate automation is gradually being adapted to reduce the human error and to minimize the loss in efficiency.
Thermal power plant basically comprises of ;
Boiler, Steam Turbine, Alternator, Ash handling plant, fuel handling plant and water treatment plants.
Various fuels like coal, bagasse, wood, cane trash, rice husk, saw dust, gas, oil etc are used in Boilers to convert their chemical energy into heat energy.
In the present scenario most of the power plants are adopting the higher range of steam pressure and temperature to reduce the specific fuel consumption of the power plant.
The power plant auxiliaries include;
Air compressors: Different kinds of compressors like reciprocating compressors, screw compressors & centrifugal compressors are generally used in all power plants.
Boiler auxiliaries: like fans & pumps of different configuration are used .For Boiler feed pumps generally HT & LT type motors are used.
Ventilation and air conditioning systems: used for office, control rooms, electrical panel rooms.
Cooling water system: Includes cooling tower or chillers with auxiliary cooling water pumps.
Lube oil system: Includes lube oil storage tanks, pumps, filtering, cooling and purifying units.

Safety health and environment in power plants:

As the thermal power industry is related to high pressure and temperature fluid, high pressure compressed air, hot, height and confined  space related works, so it becomes very vital to follow all the operation and maintenance works with safely.
Safety objectives in power plant:
1.To create safe, environment friendly and healthy environment at the work place

2.Prevent accidents and harmful effects on workers health

3.To avoid injuries to workers and damages to the plant equipments

4.To ensure full compliance with health, environment and safety policies

5.To empower employees to stop unsafe practices in work

6.Investigating the accidents and report analysis

7.To perform work hazard analysis  and risk assessment

Responsibility of Employer for safety health and environment:

1.To provide safe and healthy environment for their employees
2.Providing proper training and Personal protective equipments to all employees
3.Providing proper tools tackles
4.To eliminate unsafe conditions in the plant
5.Providing proper first aids to all employees
6.Conducting medical examinations to all employees
7.Adopting & following all disposal methods
8.Adopting & following all pollution control norms

Energy is the prime mover of economic growth and is vital to sustenance of a modern economy. Energy efficiency has assumed a critical role in our pursuit of sustainable development. The gains from energy efficiency have been harnessed the world over and India in no exception. Studies carried out by various organizations reveal that World industry has the potential to save 20 to 30% of total energy consumption.
Power plant involves all types of energies namely Mechanical energy, chemical energy, pneumatic energy, hydraulic energy, thermal energy, kinetic energy and finally electrical energy, this implies that power generation sectors have huge scope to conserve and save the energy up to extreme zero levels. Now a days there is huge competition in reducing the auxiliary power consumption of power plants.Generally, around 6 to 10% of total power generated is consumed in house by plant auxiliaries like pumps, fans, compressors, fuel handling plant, ash handling plant, water treatment plant etc.

It is said that one unit power saved is equivalent to two units of power saving.

Main contents :
1.Power generation calculations in steam Turbine
2.Specific terms used in power plants
Heat rate in power plant
Opportunities for energy conservation in power plant
Best practices for reduction of power plant Auxiliary power consumption
Vibrations in machines
Constructional materials & Welding electrodes
ESP troubleshooting


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Boiler calculations for Boiler operation Engineer Exam (BOE)

  1-Oxygen percentage in Boiler outlet flue gas is 4.9%, then what will be the percentage of excess air? We have excess air EA = O2 X 100 / (21-O2)                                    EA = 4.7 X 100 / (20-4.7)                                    EA = 30.71% 2-Calculate the Oxygen level (O2) in flue gas, if excess air is 25% We have Excess air EA = O2 X 100 / (21-O2)                                    25 = O2 X 100 / (21-O2)                                    O2 = 4.2% 3-A Boiler’s combustion system requires 5.5 kg of air for burning 1 kg of fuel, then calculate the total air required for complete combustion if its flue gas has 4.1% of O2 We have, Total air = (1 + EA/100) X Theoretical air EA = O2 X 100 / (21-O2) EA = 4.1 X 100 / (20-4.1) = 25.78% Therefore Total air = (1 + 25.78/100) X 5.5 = 6.92 kg of air per kg of fuel burnt 4-A Coal fired boiler having total heating surface area 5200 M2 produces 18 kg of steam per square meter per hour of heating surface, then calculate the Boiler cap