Thermal Power Plant: Working, Types and Diagram
Table of Contents
What is Thermal Power Plant
A power station that converts heat energy into electrical energy is called a thermal power plant. An electrical generator is connected to a steam turbine in a steam-generating cycle, which uses heat to boil water in a sizable pressure vessel to produce high-pressure steam. In a steam condenser, the low-pressure exhaust from the turbine is cooled to produce hot condensate, which is then recycled to the heating process to produce more high-pressure steam. An example of a Rankine cycle is this.
The majority of the world’s electricity is produced by thermal power plants, which make up about 60% of all power plants worldwide. They are employed in the production of electricity from a range of fuels, such as coal, natural gas, oil, and nuclear energy. Air pollution from thermal power plants, which release pollutants like sulfur dioxide, nitrogen oxides, and particulate matter, is a significant problem. By emitting greenhouse gases like carbon dioxide, they also contribute to climate change.
Thermal power plants, however, can also be a dependable and effective source of electricity. They can be used seven days a week, twenty-four hours a day, and can be scaled up or down to meet demand. Thermal power plants will need to undergo modifications to lower their emissions as the world moves toward a cleaner energy future. Utilizing cleaner fuels, like natural gas, and installing pollution control machinery can accomplish this.
How does it Work?
The most prevalent type of thermal power plant in the world, thermal plants produce about 60% of the world’s electricity. Steam is produced by coal, natural gas, or oil fired boilers, which also heat water. The steam is then used to turn a turbine that is attached to an electricity-generating generator.
Types of Thermal Power Plant
Thermal power plants can be classified into two main types:
- Conventional thermal power plants: These facilities produce electricity using a steam turbine. Burning a fuel, such as coal, natural gas, or oil in a boiler produces the steam.
- Combined cycle Thermal power plants: These power plants produce electricity using steam and gas turbines. In the first stage, electricity is produced using a gas turbine, and in the second, electricity is produced using a steam turbine. The steam turbine uses the heated water and steam produced by the gas turbine to operate.
Thermal power plants have a number of advantages, including:
- Their construction and maintenance costs are comparatively low.
- They can be constructed in a range of sizes, from tiny thermal power plants that can supply electricity to a single community to enormous plants that can supply electricity to an entire nation.
- They are dependable and able to run continuously for extended periods of time.
However, thermal power plants also have a number of disadvantages, including:
- They produce greenhouse gases that contribute to climate change, like carbon dioxide.
- They have the ability to release pollutants into the air, including nitrogen oxides and sulfur dioxide.
- They use a lot of water, which can be problematic in areas with scarce water supplies.
Thermal power plants continue to be a significant source of electricity in many nations despite these drawbacks. Thermal power plants must be modified in order to lessen emissions and their negative effects on the environment as the world transitions to a cleaner energy future.
Principle of Thermal Power Plant
“Thermal power plant” as the title infers is the place of mechanism which converts heat energy into electric power.
A large facility that transforms heat energy into electric power is called a thermal power plant. Typically, burning fossil fuels like coal, oil, or natural gas produces the heat energy. Steam is created when hot combustion gases are used to heat water in a steam boiler. After that, a turbine that is attached to an electric generator is turned by the steam. The turbine’s mechanical energy is transformed into electric power by the generator.
The world’s largest source of electricity comes from thermal power plants. They can be produced in large quantities and are dependable and effective. However, they also have a number of negative environmental effects, such as greenhouse gas emissions and air pollution. The use of high-volume combustion technologies is one way to lessen the effects of thermal power plants on the environment. These innovations enable more effective fuel combustion, which lowers emissions. Additionally, new kinds of thermal power plants that use renewable energy sources, like biomass and solar thermal energy, are being developed using high-volume combustion technologies.
Working of Thermal Power Plant
A large facility that transforms heat energy into electric power is called a thermal power plant. Typically, heat energy is produced by burning fossil fuels like coal, oil, or natural gas. Steam is created when hot combustion gases are used to heat water in a boiler. After that, a turbine that is attached to an electric generator is turned by the steam. The turbine’s mechanical energy is transformed into electric power by the generator. The world’s largest source of electricity comes from thermal power plants. They can be produced in large quantities and are dependable and effective. However, they also have a number of negative environmental effects, such as greenhouse gas emissions and air pollution.
The use of high-volume combustion technologies is one way to lessen the effects of thermal power plants on the environment. These innovations enable more effective fuel combustion, which lowers emissions. Additionally, new kinds of thermal power plants that use renewable energy sources, like biomass and solar thermal energy, are being developed using high-volume combustion technologies. The turbine shaft connected to the generator rotates with the help of this steam. The turbine impeller’s kinetic energy is transformed into electric energy by the generator.
Layout of Thermal Power Plant
Working Components of Thermal Power Plant
A thermal power plant generates electricity by performing a number of sequential steps.
The world’s largest source of electricity comes from thermal power plants. By burning fossil fuels like coal, natural gas, or oil, they produce electricity. These fuels are burned to produce heat, which is then converted into steam, which powers a turbine to produce electricity.
Typically, trains are used to transport fuel for thermal power plants from mines to the plant’s fuel storage facility. Before being fed into the boiler furnace, the fuel is then reduced in size using crushers. The fuel is burned once it is inside the boiler, producing a significant amount of heat. Water then receives this heat transfer and produces steam. After that, the steam is used to power a turbine that is attached to a generator. The turbine’s mechanical energy is transformed into electrical energy by the generator.
Although they are a dependable source of electricity, thermal power plants also have a number of negative environmental effects. Fossil fuel combustion results in the release of particulate matter, nitrogen oxides, and sulfur dioxide into the atmosphere. Asthma, bronchitis, and heart disease are just a few of the health issues that these pollutants can contribute to. Thermal power plants release greenhouse gases like carbon dioxide, which are another factor in climate change.
Thermal power plants continue to be a significant source of electricity despite their negative effects on the environment. They are dependable and relatively cheap to run. Thermal power plants are likely to continue playing a significant role in the world’s energy mix as the population of the planet grows and energy demand rises. On the other hand, treated water that has been cleaned of impurities and air that has been added to the boiler drum, where the heat from the fuel’s combustion is transferred to the water, causing it to condense into steam at a high pressure and temperature.
Flue gases from boiler exhaust typically have a high temperature, and if this heat is not used, it will result in numerous losses and decreased boiler efficiency. Therefore, this wasted heat is typically recovered by preheating the water before it is sent into a boiler or by heating the air needed for combustion. Before being released into the atmosphere through a chimney, flue gases are then allowed to pass through a dust collector or a bag filter to capture dust particles and stop air pollution.
Water Treatment Plant of Thermal power Plant
The boiler, boiler tubes, boiler accessories, and turbine blades all come into direct contact with the water and steam generated by the large amounts of plant water used in thermal power plants to rotate the turbine. The well contains a lot of dirt, suspended particulate matter (SPM), dissolved minerals, and dissolved gases like air, in addition to the normal water that is drawn from the river. If the water fed to the boiler is not treated, it will shorten the equipment’s lifespan and efficiency by corroding the surfaces and causing scaling, which could cause pressure parts to overheat and explode.
By adding alum to the water tank, suspended particles from the water are separated by gravity. The alum is added, which causes the suspended particles to coagulate and fall to the bottom of the tank by gravity as a result of an increase in density. After gravity separation, the ion exchange process is used to soften the water. These salts are eliminated from the water anion exchange and cation exchange process as the hardness is produced by the sodium and magnesium carbonates and bicarbonates.
Additionally, water contains dissolved oxygen, which when it comes into contact with surfaces like boiler tubes and surfaces, causes corrosion and fouling. As a result, adding oxygen scavengers and using a deaerator tank are both methods for removing dissolved oxygen from water. The feed water is stored in the deaerator tank, which also serves as a feed water tank. The amount of dissolved air in water is reduced by heating feed water in a deaerator tank,. Which removes the dissolved air from the water.
A boiler is a type of pressure vessel used to produce saturated steam at high pressure. Boilers with bi-drum water tubes are typically used at this high pressure and temperature.
A furnace is contained by a water tube membrane in a water-tube boiler. The boiler furnace is fed with the fuel that has been crushed by the crushers over the grate. Fuel is burned when hot air from a forced draft (FD) fan is combined with crushed fuel. A significant amount of radiation heat is produced during fuel combustion. And is transferred to the water in the membrane tubes. Water is heated by convection heat transfer as a result of the high-velocity combustion-generated flue gases that cross the convection bank of tubes. Through the feed-water pump, hot water is pumped at a high pressure into the boiler drum.
Water is circulated through a boiler’s low-temperature tubes, known as downcomers,. While steam is carried through a boiler’s high-temperature tubes, known as risers. This results in efficient water circulation, which keeps the tubes from overheating. Although the steam is leaving the boiler at a saturated pressure and temperature,. It loses a lot of heat on the way to the turbines. Therefore, a steam Superheater is installed in a radiate section of a boiler to raise the temperature. And dryness fraction of the steam without increasing its pressure as well as to account for the transportation temperature losses in order to improve the quality of the steam.
Installing an Economiser or Water Preheater to warm the boiler’s feed water and Air Preheaters to pre-heat the air coming from the Forced Draft Fan necessary for the combustion of fuel allows for the extraction of waste heat from the exhaust gases leaving the boiler, which are typically at high temperatures. By installing this equipment, you can increase efficiency by lowering the temperature of the flue gas. In order to lessen air pollution, the flue gases are allowed to pass through dust collectors, bag filters, and occasionally wet scrubbers in order to remove some of the ash particles that are present in the flue gases as well as to lower their sulfur content.
Using an induced draft (ID) fan with a fixed capacity and head to avoid any backpressure,. The flue gases are drawn through this machinery. Following the ID fan, a chimney is used to exhaust flue gases into the atmosphere.
What is Turbine
Steam’s kinetic and pressure energy can be used to produce useful work through the use of a turbine, a mechanical device. Steam leaves the superheater and enters the turbine,. Where it expands, loses its kinetic and pressure energy, and turns the turbine blade, which turns the turbine shaft that is attached to the blades. The generator is then rotated by the shaft, turning the kinetic energy into electrical energy.