Wet Electrostatic Precipitators (WESP)
The polishing technology for everything dry collection can’t catch: sub-µm aerosols, acid mist, SO3, condensable tars and pyrolysis fume. A high-voltage corona charges the contaminant; water-washed collection plates carry it down. Continuous wetting prevents the re-entrainment that fouls dry ESPs.
Outlet PM < 10 mg/Nm3 achievable. Stainless modular fabrication. Pairs with quench tower or packed-bed pre-conditioning.
Typical duties:
- Acid plant tail-gas polishing — SO3 / H2SO4 mist
- Roaster and calciner offgas
- Pyrolysis and biochar fume — e.g. Pyrocal (Queensland) two WESP units on sticky tars
- Sticky and condensable particulate — e.g. CSR Ingleburn WESP upgrade (NSW), 6 stainless modules to NSW EPA Licence 13087
- Blue-plume mitigation
Dry Electrostatic Precipitators
The Vortex Engineering Group operates the largest dry ESP range in New Zealand. Dry ESPs use high-voltage corona discharge and grounded collector plates to remove particulate from dry gas streams — no liquor recirculation, simple downstream handling, well-suited to high-flow / moderate-load duties.
Typical duties:
- Iron / steel sintering and pelletising
- Cement and lime kiln offgas
- Furnace dust capture
- Glass furnace offgas — e.g. O-I Glass / Visy Glass (Auckland)
- Iron-process ESP — e.g. PT Krakatau / PT Meratus Jaya (Indonesia)
Modules with rapping systems, hoppers, gas-distribution baffles and TR sets matched to the duty. Materials selected for gas chemistry — carbon steel, stainless, or alloyed shell.
Engineering envelope
Both wet and dry ESPs delivered under a unified engineering envelope:
- Particulate size — 0.01 µm and up
- Outlet PM — < 10 mg/Nm3 achievable (WESP duty)
- Gas inlet (WESP) — cooled / saturated, 60–80 °C typical
- Configurations — plate, tubular, multi-module
- Materials — 304 / 316 SS, alloy options, carbon steel for dry duty
- Power — HV TR sets, arc-quench logic, PLC control
- Pairs with — quench tower, packed-bed scrubber, venturi pre-scrubber
ISO 9001 / 14001 / 45001 aligned. AS/NZS 5131 structural, AS/NZS 1554.6 welding, ASME IX / VIII where required. Process guarantees written project-by-project against measured inlet conditions and target outlet limits.
Where we've delivered ESPs
Wet and dry electrostatic precipitator installations across mining, building materials, biomass and acid-plant duties. Hover over any location to see the project.
Frequently asked questions
Dry ESP vs wet ESP — what is the difference?
A dry ESP collects dry particulate from hot, high-flow gas; a wet ESP (WESP) handles sub-micron aerosols, acid mist, SO3 and oily/condensable fume using continuous irrigation.
When do I need a WESP?
For sub-micron aerosol, acid mist, SO3 or oily/condensable fume — where dry collection or inertial scrubbing cannot meet the limit. A WESP reaches outlet PM below 10 mg/Nm3.
ESP vs baghouse vs wet scrubber?
ESPs suit high-flow particulate including high temperatures; baghouses suit dry filterable dust; wet scrubbers suit soluble gases and condensable or sticky duties. The right pick depends on particle size, temperature and gas chemistry.
Do you support legacy ESPs?
Yes — we supply spares and servicing for JOY-Western, TAPC, Lurgi, Flakt and Lodge Cottrell electrostatic precipitators.
Do you guarantee outlet emissions?
Yes — against your measured inlet conditions and target outlet limits.