Deaerator Case Studies

Replacement Vent

CHICAGO HEATER REPLACEMENT VENT


Problem: The deaerator had water out the vent.

Chloride Attack

CHLORIDE ATTACK TRAY ENCLOSURE


Problem: The tray enclosure was ineffective due to chloride attacks on the deaerator.

corrosion

CORROSION


Problem: Corrosion pits were observed in the deaerator storage section.

Deaerator Erosion

DEAERATOR EROSION


Problem: A deaerator was thinning out due to erosion underneath the tray stack.

Deaerator Explosion

DEAERATOR EXPLOSION AND FAILURE


Problem: This deaerator had a catastrophic explosion and catastrophic failure due to non-inspection of the deaerator and/or inadequate inspections.

Dogleg pipe

DOG LEG VENT PIPE FAILURE


Problem: Many manufacturers provide a dog leg type vent with a miter joint which typically fails due to inadequate welding where the vent pipe supports the valve plate.

FAC

FLOW ACCELERATED CORROSION (FAC)


Problem: Vessel had severely high corrosion due to FAC.

Heater Steam Erosion

HEATER STEAM EROSION


Problem: Various locations of the deaerator and heating section can be eroded by steam due to inadequate downcomer sizing, inadequate baffling and inadequate water distribution.

High Oxegen Levels

HIGH OXYGEN LEVELS


Problem: The customer complained about poor dissolved oxygen readings.

Scrubber Modification

SCRUBBER MODIFICATION


Problem: The deaerator scrubber was inadequately sized and destructed due to high velocities.

corrosion

SPRAY DEAERATOR CORROSION


Problem: The deaerator is open to oxygen degradation due to non containment of the oxygen in the vessel.

Water Bypass

SPRAY DEAERATOR WATER BYPASS


Problem: Water is bypassed in this spray deaerator due to high flow rates and/or inadequate sizing of tray pans

Stress crack

STRESS CRACK IN VESSEL SHELL


Problem: Cracking in deaerators is most often attributed to corrosion fatigue, where a crack results from a cyclic stress in a corrosive environment.

Tray Box Support Pitting

TRAY BOX SUPPORT PITTING


Problem: Pitting was noticed on the supports of tray box.

tray enclosure support wear

TRAY ENCLOSURE SUPPORT WEAR


Problem: The tray enclosure supports were ruined due to relatively high steam velocities and water erosion.

Tray Hold Downs

TRAY HOLD-DOWNS


Problem: Tray holdowns on older units rely on sheer force to the tray box to compress the trays and hold the trays down.

Tray upsets

TRAY UPSETS


Problem: Tray upsets are common in the deaerator industry if proper tray hold-downs and baffling are not provided.

Waterbox Spray Pattern

WATERBOX SPRAY PATTERNS


Problem: Spray valves were improperly located over the trays allowing for water carry over to the vent

Weld Overlay

WELD OVERLAY ON DEAERATOR


Problem: Excessive pitting and/or erosion due to high velocity of steam and the deaerator will not perform properly.