For more than 50 years, HEE-Duall has stood as an industry-leading pioneer in the engineering and manufacturing of high-efficiency air pollution control systems and corrosion-resistant ventilation technologies. Specializing in advanced wet scrubbing architectures, HEE-Duall provides tailored process solutions designed to neutralize and eliminate hazardous gas streams, corrosive mists, noxious vapors, and fine chemical particulates from industrial exhausts. By combining sophisticated chemical engineering fluid dynamics with premium thermoplastic and composite material fabrication, HEE-Duall systems ensure strict environmental compliance, safe work environments, and long-term infrastructure protection in the world’s most corrosive manufacturing environments.

The operational framework of HEE-Duall revolves around custom-engineered durability and low-maintenance lifecycle efficiency. Rather than installing standardized, off-the-shelf air scrubbers that face accelerated chemical erosion or premature packing blinding, HEE-Duall utilizes precise thermodynamic and chemical-absorption modeling to configure every system. From horizontal cross-flow scrubbers deployed in tight ceiling spaces to massive vertical counter-current towers handling high-volume process airstreams, their technology optimizes the liquid-to-gas (L/G) ratio. This ensures maximum mass transfer and chemical neutralization while maintaining exceptionally low operating pressure drops to reduce facility fan energy consumption.

For more than two decades, Trotter Equipment Company has partnered with HEE-Duall across Ohio, Indiana, Kentucky, and West Virginia. Our specialized field engineers bridge HEE-Duall’s world-class custom fabrication and corporate laboratory capabilities with Trotter’s hands-on regional process application experience. We work collaboratively with regional processing operations from initial exhaust stream airstream analysis and ventilation configuration through turnkey structural equipment design, system installation, and long-term preventive maintenance and optimization diagnostics.

HEE-Duall Advanced Wet Scrubbing & Air Control Technologies

HEE-Duall’s air pollution control system portfolio comprises comprehensive, integrated ventilation configurations designed to safely capture, transport, and scrub highly reactive and aggressive gas compositions before environmental stack discharge.

Packed Bed Wet Scrubbers

HEE-Duall packed bed wet scrubbers are custom-designed systems engineered for high-efficiency gas absorption and multi-contaminant chemical neutralization. Utilizing random or structured internal packing media beds continuously flooded with chemical reagents, these vessels maximize the contact surface area between the gas stream and the scrubbing liquid.

• Vertical Counter-Current Scrubbers (PT Series) — Engineered for maximum gas absorption efficiency within a minimal structural footprint. The process exhaust gas enters the bottom of the vertical tower and moves upward while the neutralizing scrubbing liquid is sprayed downward over the packing bed, ensuring continuous contact with fresh reagent for optimal contaminant removal.
• Horizontal Cross-Flow Scrubbers (HF Series) — Designed specifically for facility layouts with low overhead clearance or where multi-stage chemical scrubbing is required within a single compact unit. The gas stream passes horizontally through one or more independent packing beds while the scrubbing liquid cascades vertically downward, allowing different chemical reagents to target separate pollutants sequentially.
• High-Efficiency Packing Media — Outfitted with high-surface-area random dumping media, such as Tri-Packs or Tellerettes, configured to disrupt gas flow paths and maximize fluid contact time without causing high static pressure drop or mechanical nesting.
• Integrated Reagent Re-Circulation Systems — Equipped with integrated chemical storage sumps, high-capacity chemical pumps, automated spray distribution headers, and non-clogging clog-resistant spray nozzles designed to maintain uniform bed flooding.

Venturi Scrubbers & High-Energy Particulate Catchers

For process streams containing both hazardous chemical gases and heavy sub-micron particulate loads, HEE-Duall designs heavy-duty Venturi scrubbing systems that utilize high-velocity shear forces to trap fine dust profiles inside atomized liquid droplets.

• Adjustable Throat Venturi Systems — Features a variable mechanical throat configuration that allows operators to adjust internal gas velocities and pressure differentials, accommodating varying plant production rates while maintaining peak particulate collection efficiencies.
• Cyclonic Droplet Separators — A close-coupled downstream separation chamber that utilizes centrifugal force to rapidly isolate wet, particulate-laden droplets from the cleaned exhaust gas stream, preventing downstream liquid carryover.

Corrosion-Resistant Industrial Ventilation & Fans

Transporting highly corrosive chemical exhausts requires ventilation equipment built to withstand continuous chemical attack. HEE-Duall manufactures a comprehensive line of industrial fans and air moving components built from advanced non-metallic composites.

• FRP Centrifugal Fans (CN Series) — High-capacity exhaust blowers constructed from premium Fiberglass Reinforced Plastic (FRP). Features aerodynamically balanced FRP impellers and vinyl ester resin housings designed to handle heavy static pressures and corrosive vapor flows without the scaling or tracking failures typical of coated metal fans.
• Corrosion-Resistant Inline Fans — Compact, direct-drive or belt-drive inline exhaust fans fabricated from PVC, Polypropylene, or FRP, optimized for space-restricted laboratory exhaust lines or secondary chemical storage venting.
• Engineered FRP & Thermoplastic Ductwork — Custom-fabricated exhaust ducting arrays, containment hoods, blast gates, and control dampers built to SMACNA corrosion-resistant plastic design criteria, ensuring zero-leak conveyance from the source hood to the scrubber stack.

Industries & Chemical Applications Served

• Semiconductor & Electronics Fabrication — Ultra-high efficiency removal of highly toxic and corrosive cleanroom exhaust gases, including hydrofluoric acid (HF), hydrochloric acid (HCl), silicon tetrachloride, and volatile doping agents.
• Chemical Processing & Specialty Synthesis — Neutralization of harsh acid gases, chlorine vapors, sulfur dioxide ($SO_2$), ammonia ($NH_3$), and caustic chemical fumes produced during bulk blending and chemical reactions.
• Municipal Wastewater & Odor Control — Elimination of high-concentration hydrogen sulfide ($H_2S$), organic mercaptans, and municipal odors at headworks, sludge holding tanks, and pump stations utilizing multi-stage chemical scrubbing configurations.
• Metal Finishing, Pickling & Electroplating — Capture and containment of aggressive chromic, sulfuric, and nitric acid mists rising from open chemical process tank bays, preventing structural degradation of plant buildings.
• Pharmaceutical & Life Sciences Manufacturing — Venting and scrubbing of reactor vessel streams, extraction fumes, and volatile organic compound (VOC) abatement to satisfy strict air-quality permits.

Services

• Engineering / Design — Comprehensive exhaust volume and static pressure calculations, custom chemical reagent selection modeling, scrubber system sizing, footprint optimization, and retrofitting existing obsolete scrubbers with updated internal components.
• Scrubber Inspection & Performance Tuning — Comprehensive internal inspections, dynamic air-velocity mapping, liquid flow optimization, gas-leak containment screening, and systematic pressure drop diagnostics to ensure optimal scrubber operational parameters.
• Field Troubleshooting & Packing Replacement — Root-cause analysis of liquid carryover bugs, chemical scale removal, automated pH/ORP control sensor diagnostics, exhaust fan vibration testing, and turnkey removal and replacement of fouled internal packing beds.

PARTS

• High-Surface-Area Random Tower Packing Media (Tri-Packs, Tellerettes, Polypropylene Rings)
• Non-Clogging Thermoplastic Spray Nozzles & Liquid Distribution Headers
• High-Efficiency Chevron Blade and Mesh Pad Mist Eliminator Assemblies
• FRP Exhaust Fan Impellers, Drive Shafts, and Corrosion-Protected Bearings
• Automated pH and ORP Control Sensors, Transmitters, and Chemical Metering Pumps
• Thermoplastic Submersible and Magnetic-Drive Re-Circulation Pump Units
• Differential Pressure Gauges, Transmitters, and Purge Line Connection Kits
• Custom FRP Blast Gates, Damper Blades, Control Actuators, and Flex Connectors
• Vessel Inspection Port Covers, High-Containment Gaskets, and Access Hatch Seals
• Sub-Assembly Replacement Modules for Multi-Stage Horizontal Scrubber Retrofits