XeteX Air Handling Blog

HVAC System Design for Waste Water Treatment Plants

Written by XeteX | 4/25/25 9:18 PM

HVAC system design for a waste water treatment plants (WWTPs) requires careful consideration of the unique environmental challenges to ensure: 1) safe operation with explosion-proof design; 2) system longevity with corrosive-resistant materials; and 3) air quality with energy recovery ventilation.

Understanding WWTP HVAC System Requirements

The first step in effective HVAC system design for a wastewater treatment plant involves recognizing its distinct environmental conditions. WWTPs are harsh environments holding high concentrations of hydrogen sulfide, mercaptans, methane gas, and organic compounds that create potentially explosive conditions. HVAC systems must operate without any risk of sparking.

Corrosion is a significant concern for WWTP HVAC systems due to the high levels of moisture and corrosive chemicals present in the air. Traditional HVAC materials degrade quickly in a WWTP environment, leading to frequent maintenance and costly replacement.

Adding to the explosive potential and corrosive nature is the need for proper ventilation. Adequate make-up air must be designed into the air-side system to maintain safe levels of gases within the pump station, wet/dry well areas, de-watering stations and headworks sectors.

Volatile organic compounds (VOCs) and corrosive gases present in WWTPs pose unique challenges for HVAC systems. It is crucial that HVAC system designs prioritize safe operation with explosion-proof equipment; long-lasting performance with corrosion-resistant material selection; and optimal air quality with proper ventilation.

An XeteX Custom HRV with Explosion-Proof Design and All-Aluminum Construction

Designed for a waste water treatment plant, this XeteX custom heat recovery ventilator (HRV) features Class 1, Div 2 explosion-proof equipment for safe, spark-free operation. All-aluminum construction with epoxy-protective coated parts ensure long-lasting performance reducing maintenance and replacement costs.

The HRV design also integrates an epoxy-coated aluminum flat plate heat exchanger for energy recovery and ventilation. It draws in fresh outdoor air for ventilation, indoor air quality, and energy efficiency. The heat exchanger works by recycling heat from the exhausted air to preheat the fresh incoming air without cross contamination of air streams. While the heat exchanger draws in fresh outdoor air, it also reduces energy costs. 

HRV Performance

Model: XHS-30-48-RT-BP-HD
Dimensions: 86”H x 70”W x 204”W
Energy Recovery: Epoxy-coated flat plate heat exchanger (sensible)
Energy Effectiveness: 68% Winter / 59% Summer
Heating Type: Direct-fired gas furnace
Supply CFM: 4,000 CFM
Heating Capacity: 400 MBH

All-Aluminum Construction

  • Outdoor unit
  • 2” double wall aluminum casing
    • 0.063 aluminum exterior casing
    • 0.063 aluminum interior casing with injected foam insulation (R-14)
  • Aluminum 0.080 floor with 2” PolyIso foam (R-5.7/in)
  • Aluminum drain pan
  • 6” structural aluminum frame (2.83 lb/ft) with welded lifting lugs; acrylic paint
  • 0.063 aluminum roof
  • Aluminum SA and EA blower wheels, cones and frames; corrosion-resistant coated EA wheel
  • Aluminum mesh filters OA

Features

  • Spark-resistant EA coated fan with explosion-proof motor
  • Explosion-proof sensors: RA & EA Temperature sensors and Room and Supply Temperature sensors
  • Explosion-proof switches: filter pressure switch for RA Filters
  • Factory-mounted Carel DDC programmed unit controls

HRV Components

A. 2” MERV 8 RA with aluminum rack
B. Epoxy-coated aluminum flat plate heat exchanger with modulating face & bypass damper control
C. Direct-fired gas furnace 
D. SA TEFC fan motor
E. 1” aluminum mesh filter
F. 2” MERV 8 OA with aluminum rack
G. EA explosion-proof fan motor 

XeteX resolves HVAC system design requirements for WWTPs: ensuring safe operation with explosion-proof equipment; withstanding harsh conditions with non-corrosive materials and protective coatings; and maintaining air quality with energy recovery ventilation.

Learn more about XeteX air handling and energy ventilation solutions for waste water treatment plants!