COAL-FIRED POWER PLANT

COAL-FIRED POWERPLANTPresented by:Shakir b abd yazibMuhamad bukhari b abd basir

INTRODUCTION

Coal MiningSurface MiningStrip Mining

Underground Mining

OVERVIEW

Coal Power Plant OperationPOWER PLANTPROS OF COAL POWERCons OF COAL FIRED POWER PLANTOn the other hand, there are also some significant disadvantages of coal fired plants including Greenhouse Gas (GHG) Emissions, mining destruction, generation of millions of tons of waste, and emission of harmful substances.Greenhouse gas emissions. It cannot be denied that coal leaves behind harmful byproducts upon combustion. These byproducts cause a lot of pollution and contribute to global warming. The increased carbon emissions brought about by coal fired plants has led to further global warming which results in climate changes.

Mining destruction. Mining of coal not only results in the destruction of habitat and scenery, but it also displaces humans as well. In many countries where coal is actively mined, many people are displaced in huge numbers due to the pitting of the earth brought about by underground mining. Places near coal mines are unsafe for human habitation as the land could cave in at anytime.

Generation of millions of tons of waste. Millions of tons of waste products which can no longer be reused are generated from coal fired plants. Aside from the fact that these waste products contribute to waste disposal problems, these also contain harmful substances.

Emission of harmful substances. Thermal plants like coal fired plants emit harmful substances to the environment. These include mercury, sulfur dioxide, carbon monoxide, mercury, selenium, and arsenic. These harmful substances not only cause acid rain but also are very harmful to humans as well.

The Process

In a coal-fired steam stationmuch like a nuclear stationwater is turned into steam, which in turn drives turbine generators to produce electricity. Heres how the process works.1. Heat is created

Before the coal is burned, it is pulverized to the fineness of talcum powder. It is then mixed with hot air and blown into the firebox of the boiler. Burning in suspension, the coal/air mixture provides the most complete combustion and maximum heat possible.

2. Water turns to steam

Highly purified water, pumped through pipes inside the boiler, is turned into steam by the heat. The steam reaches temperatures of up to 1,000 degrees Fahrenheit and pressures up to 3,500 pounds per square inch, and is piped to the turbine.

3. Steam turns the turbine

The enormous pressure of the steam pushing against a series of giant turbine blades turns the turbine shaft. The turbine shaft is connected to the shaft of the generator, where magnets spin within wire coils to produce electricity.

4. Steam turns back into water

After doing its work in the turbine, the steam is drawn into a condenser, a large chamber in the basement of the power plant. In this important step, millions of gallons of cool water from a nearby source (such as a river or lake) are pumped through a network of tubes running through the condenser. The cool water in the tubes converts the steam back into water that can be used over and over again in the plant.

The cooling water is returned to its source without any contamination, and the steam water is returned to the boiler to repeat the cycle.