Nuclear power station


(con_eng) #1

[LEFT][FONT=Arial][SIZE=3]A Nuclear power station uses nuclear energy for generating electrical energy.This power station is generally located far from populated areas. This kind of power station can be used to produce large amounts of electrical energy. In most countries these power stations are used as Base loadpower stations. This is because they can take several days to be warmed up and brought on-line.

[U][B]Operation

[/b][/u] Heavy elements such as Uranium (U235) or Thorium (Th232) are subjected to nuclear fission in a reactor to produce steam at high temperatures and pressure.
Steam runs a steam turbine which converts this energy into mechanical energy.
The turbine drives the alternator which converts mechanical energy into electrical energy.

Future generations will want to depend more on this type of electricity generating power station (and other renewable energy sources), due to a fast increasing depletion of fuels(Coal). There are a number of [/size][/font] [FONT=Arial][SIZE=3]construction projects currently underway for this kind of power station around the world.

Constituents of Nuclear power station
Figure 2 shows a schematic of the general arrangement of a nuclear power station. The constituents of the schematic are labelled in the table below as follows:


Key for figure schematic
(1)–reactor block (2)–cooling tower (3)–reactor (4)–control rod (5)–support for pressure (6)–steam generator (7)–fuel element (8)–turbine (9)–generator (10)–transformer (11)–condenser (12)–gaseous (13)–liquid (14)–air (15)–air (humid) (16)–river (17)–cooling-water circulation (18)–primary circuit (19)–secondary circuit [/size][/font]
(20)–water vapor (21)–pump


Location of Nuclear power station:
influencing factors

Availablility of water: Sufficient water must be available for cooling, thus plant must be situated near a river or by sea-side
Disposal of waste: Waste produced is generally reactive, and thus must be disposed of properly to avoid health hazards. Waste must be disposed in deep trench or in sea away from shore.
Distance from populated areas: Must be far away from populated areas as there may be radio-active particles in the atmosphere near plant. However, the radio-activity released by a nuclear power plant is significantly less than a similar coal-powered plant
Transportaion facilities:

The site should be accessible by rail and(or) road for ease in transporting equipment & machinery.
Feasibility of this power station:
To be able to understand the reason why most contries are turning to the wide use of this kind of power station, we must consider the amount of energy produced by the fuel used by this kind of power station. 1 kg of Uranium (U235) can produce as much energy as 4500 Tons of high grade coal. This is more than enough to supply a metropolitan city for a month!
This schematic diagram must be properly understood. it is the basis upon which nuclear power station designs are done. The individual power station complexity may differ slightly to the shematic and yet over and above that will use the same principle.

[/left]