Electrostatic precipitator

ESP Rectifer transormer

M.G.Morshad / ACM Transformer Mtce / TPS II

Principle o operation

• Electrodes at high voltage create a corona effect (ionized atmosphere)

surrounding them. • This charges the passing particles. Once charged, particles are subject to a transverse electrostatic force that pulls them toward the collecting plates. • Plates are periodicall !rapped" (vibrated) to ma#e the collected particles fall down into a receiver hopper.

Principle o operation

• Electrodes at high voltage create a corona effect (ionized atmosphere)

surrounding them. • This charges the passing particles. Once charged, particles are subject to a transverse electrostatic force that pulls them toward the collecting plates. • Plates are periodicall !rapped" (vibrated) to ma#e the collected particles fall down into a receiver hopper.

Back corona $$$$$$$$$$$$$$$$$$$$$ - - - - - - - - - - - - - - - - - - Spark $et%een layers o d"st particles

-

#eatively chared emittin electrodes

% - - - - - - - - - - - - - - - - - -

#eativel y chared d"st particles

!ih resistive d"st particles

Positively chared collectin plates

$$$$$$$$$$$$$$$$ $$$$$ $ In

case of high resistive dust ( dry dust) , dust layer l ayer creates an insulation beteen the !ositively charged collecting !late and negatively charged dust !articles"

 In

such condition, s!ar# / arc ithin the layer of dust !article is formed ith the decrease of $% (&')" This !henomena is #non as '$ '*+*"

 s

a result of s!ar# s!ar# / arc formation formation , field current (m ) gets increased increased ith substantial decrease in field voltage $% (&')"

To

avoid bac# corona, field voltage $%(&') has to be reduced sufficiently, but such measures finally collection efficiency of the field

'oltae ( c"rrent characteristics m ( &') 1ield Short

ac# 'orona 0one *!erating 0one $% ( &') 2 *!erating 0one 3

4ith the increase of field voltage 5$% (&')6, field current (m) increases linearly and no s!ar# is emitted"

ac# 'orona 7one 3

S!ar# starts emitting causing decrease in field voltage $%(&') ith high increase in field current (m)

1ield short 3

S!ar# !ersist continuously causing field voltage $%(&') to become 7ero ith ma8imum flo of field current (m)

Parameters a)ect the perormance o ESP &. 'as Temperature

 ormally 9SP is designed to o!erate in the tem!erature range :;2- uired before installing the transformer after re!air and rectification"

Characteristics o silicon oil

Principle o operation &e!ending u!on gas tem!erature, dust resistivity and gas velocity folloing !arameters are set:"uni !ulse mode/ Semi !ulse mode ,