CNWINNEX Explosion-Proof Combined Air Handling Unit | Modular Explosion-Proof AHU for Hazardous Areas

CNWINNEX Explosion-Proof Combined Air Handling Unit | Modular Explosion-Proof AHU for Hazardous Areas

The explosion-proof combined air handling unit (AHU) is a modular air treatment equipment assembled from various air handling sections. The unit carries no cold or heat source of its own and delivers multiple functions including explosion-proof cooling, dehumidification, humidification and heating. It is mainly designed for industrial sites where explosive atmospheres formed by flammable gases or vapours of Group ⅡA, ⅡB, ⅡC and temperature classes T1~T4 mixed with air may exist. The unit is designed and manufactured in strict compliance with ATEX Directive 2014/34/EU and the EN 60079 series explosion protection standards. Explosion-proof marking: Ex db mb IIC T4 Gb, suitable for Zone 1 and Zone 2 explosive hazardous areas. All electrical components and operating circuits are fully treated for explosion protection. Complete explosion-proof technical documentation is supplied to support HSE review and site acceptance for chemical, oil & gas and pharmaceutical projects worldwide.

The unit adopts a modular design with single or multiple functional sections. Various standard sections are available for design institutes and users to select and combine according to project requirements. Custom non-standard design and manufacturing are available for wide applications across industries.

Key Product Advantages

●        Explosion protection: Advanced explosion-proof technology ensures safe and reliable protection, compliant with ATEX Directive 2014/34/EU and EN 60079 series standards

●        Modular structure: Modular double-layer sandwich panel structure with polyurethane core, clip-lock fastening, flat continuous panels with smooth appearance and no joints

●        High air tightness: High-elasticity sealing strip for face sealing, air leakage meeting clean air conditioning requirements, good thermal insulation and anti-condensation

●        Excellent corrosion resistance: High-quality color-coated steel, galvanized steel, cold-rolled steel and sections, phosphated and electrostatic painted, with anti-corrosion treated fasteners

●        Multiple heat exchanger designs: Various fin types, fin spacing, circuits and row numbers to meet thermal performance requirements of different applications

●        Dry condensate pan: Sloped pan ensures smooth condensate drainage, keeping the pan dry and minimizing health hazards

●        Low noise & energy saving: High-efficiency low-noise double-inlet centrifugal explosion-proof fans, strictly dynamically and statically balanced, with advanced anti-static treatment

●        Easy installation: Sections joined on site by clamping devices and bolts, reducing assembly time, and available for on-site knockdown assembly

●        Easy maintenance: Air-tight plastic-steel maintenance doors with clip-lock structure for convenient opening and closing, facilitating internal component maintenance

●        Special-purpose units: Customizable for outdoor, clean room, pharmaceutical plant, hospital operating room and micro-electronics room applications

●        Mechatronics: Optional frequency inverter, fan starter and automatic control devices for year-round energy-saving operation, with communication interface for building automation network group control

Modular Functional Section Introduction

        ●        Fresh & return air mixing section: Fresh/return air openings located at end, top or side faces per design, with optional explosion-proof regulating damper and manual or electric actuators.

●        Filter section: Pre and medium efficiency filters with diamond bag and four-pleat bag filters, high-quality polyester non-woven media, quick-install/removal filter mechanism, differential pressure indication and alarm device.

●        Fresh & exhaust section: Primary return air damper installed, with exhaust and fresh air openings on top, allowing proportional mixing of fresh air and primary return air; damper with manual, electric or pneumatic actuators.

●        Intermediate (maintenance) section: Serves as filter section connection and internal inspection lighting; required before filter section and after/before cooling coil, heating and silencer sections.

●        Secondary return air section: Intermediate section connecting secondary return air duct, with adjustable damper on top and manual, electric or pneumatic actuators; may be combined into fan section.

●        Cooling coil section: Coil constructed with 4/6/8-row copper tubes and aluminum fins with double flanged corrugated edges; large bend heat exchanger reduces 60% of welded elbows for higher heat transfer efficiency; advanced mechanical expansion ensures contact performance.

●        Heating section: High-efficiency heat exchanger of 1/2/4-row steel tube wound fin or copper tube aluminum fin, with steam or hot water as medium.

●        Energy recovery section: Rotary wheel heat recovery unit exchanging energy between indoor exhaust air and outdoor fresh air; preheats fresh air in winter and precools in summer with recovery efficiency about 70%.

●        Supply fan section: S-type horizontal air supply with soft connection at fan outlet and spring vibration-isolated steel base for floor installation, equipped with high-efficiency double-inlet centrifugal explosion-proof fan; H-type top vertical air supply with flange connection at top, fan treated with advanced anti-static technology.

Typical Applications

Chemical workshops, oil & gas production plants, hazardous material workshops, pharmaceutical explosion-proof workshops, clean rooms, hospital operating rooms, micro-electronics rooms, energy storage plants and other Zone 1 / Zone 2 hazardous areas containing Group ⅡA / ⅡB / ⅡC, T1~T4 explosive gas mixtures.

●        Humidification section: Three options available — dry steam humidifier (manual SZS, pneumatic QZS, electric DZS), high-pressure spray humidification (direct-coupled high-pressure pump pressurizing water to 0.35MPa with fine atomization, SMD about 38.6μm, humidifying efficiency five times higher with built-in water filter) and wet-film humidification.

●        Silencer section: Provides impedance-composite plate silencer and metal micro-perforated plate silencer; the latter features high-temperature resistance, moisture resistance and no dust generation.

●        Electric heating section: Advanced PTC heating element heats air, suitable for sites without hot water or steam heat sources.

●        Flow equalizing section: Diffuser plate flow equalization with good effect and low air resistance, installed after fan section to equalize cross-section air velocity.

●        Air outlet section: Outlet openings located at end, top or side faces per design, with regulating damper and manual, electric or pneumatic actuators.

●        Maintenance section: Maintenance doors provided as required with negative-pressure and positive-pressure types; plastic-steel frame construction with good sealing, convenient opening and space saving.