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Arrays java

                         Arrays ==================================   1. Introduction:              indexed collection of homogenous data.             Advantage:                  we can represent the huge number of values / data using a single variable.         Disadvantage:                  Arrays are fixed in size.                       ==> once array size fixed we can't increase or decrease the size of an array.            ...

PPE UNIT-I Notes

POWER PLANT ENGINEERING UNIT -I

UNIT-I ==> Dust Collectors

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  SMOKE AND DUST REMOVAL             In coal fed furnaces the products of combustion contain particles of solid matter floating in suspension. This may be smoke or dust. The production of smoke indicates that combustion conditions are faulty and amount of smoke produced can be reduced by improving the furnace design.             Dust particles are mainly ash particles called fly ash intermixed with some quantity of carbon ash material called cinders. Gas borne particles larger than 1μ in diameter are called dust and when such particles become greater in size than 100p they are called cinders. Smoke is produced due to the incomplete combustion of fuels, smoke particles are less than 10p in size.             The disposal smoke to the atmosphere is not desirable due to the following reasons: 1. A smoky atmosphere i...

UNIT-I ==> Feedback water treatment

  Boiler Feed Water Treatment Boiler feed water is an essential part of boiler operations. The feed water is put into the steam drum from a feed pump. In the steam drum, the feed water is then turned into steam from the heat. After the steam is used it is then dumped to the main condenser.  The boiler receives the feed water, which consists of varying proportions of recovered condensed water (return water) and fresh water, which has been purified in varying degrees (make up water). The make-up water is usually natural water either in its raw state, or treated by some process before use. Feed-water composition therefore depends on the quality of the make-up water and the amount of condensate returned to the boiler. The steam, which escapes from the boiler, frequently contains liquid droplets and gases. The water remaining in liquid form at the bottom of the boiler picks up all the foreign matter from the water that was converted to steam. The impurities must be blown down by t...

UNIT-I ==> pulverized coal, Ash Handling System

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  Pulverized coal:      Coal is pulverized (powdered) to increase its surface exposure thus permitting rapid combustion. The efficient use of coal depends greatly on the combustion process employed. For large-scale generation of energy, the efficient method of burning coal is confined still to pulverized coal combustion. The pulverized coal is obtained by grinding the raw coal in pulverising mills. The various pulverising mills used are as follows: ( i ) Ball mill                                                                                                          ( ii ) Hammer mill ( iii ) Ball and race mill            ...