DETECTORS
Dry Electrolytic Conductivity Detector - DELCD
Overview
TheDryElectrolyticConductivitydetector,orDELCD, isselective
tochlorinatedandbrominatedmolecules. Itdiffersfrom the traditional
wetELCD in that itdoesnotuseasolventelectrolyte,and the reaction
productsaredetectedinthegaseousphase. TheSRIDELCDisavailable
aloneor incombinationwith theFIDdetector. On itsown, thedetection
limitsof theDELCDare in the lowppbrange. Incombinationwith the
FID, itsdetection limitsare in the lowppm range. TheFID/DELCD
combinationenables theoperator toreliably identifyhydrocarbonpeaks
detectedbytheFIDashalogenatedornot. BecausetheDELCDoperates
at1000
o
C, itcan tolerate thewater-saturatedFIDeffluent,measuring the
chlorineandbrominecontentsimultaneouslywiththeFIDmeasurement
of thehydrocarboncontent. Allhydrocarbonsareconvertedby theFID
flame toCO
2
andH
2
Oprior to reaching theDELCD, thuspreventing
contaminationof theDELCDby largehydrocarbonpeaks.
FID / DELCDComboDetector
DELCD reaction
chamber insulation
FIDcollector
electrode
FID flameport
assembly
FID ignitor
Hydrogen
supply
Air supply
FID ignitor
&DELCD
heater
terminal
FIDcollector
terminaland
gainswitch
DELCDcollector
& thermocouple
terminaland
gainswitch
FIDheater
block
FID
DELCD
DELCDcollector
& thermocouple
leads
DELCDonan8610CGC
DELCD
heater
terminal
DELCDcollector
& thermocouple
leads
Close-upof thesame
DELCD detector
Platinum
wires (3)
DELCD
collector
assembly
terminal
DELCD -À lacarte
