Acid fume scrubber system

This system is engineered for water-soluble acid gases, including hydrochloric acid (HCl), nitric acid (HNO₃), sulfuric acid (H₂SO₄), hydrofluoric acid (HF), and chromic acid (CrO₃) mists. The scrubbing liquid chemistry must be matched to the specific pollutant for effective neutralization.

Under standard design conditions with proper chemical dosing, a single-stage vertical counter-current scrubber like this one can achieve over 95% removal for highly soluble gases like HCl. By adding a second scrubbing stage, removal efficiencies can be increased to well over 99%. The exact efficiency depends on factors like pollutant solubility, concentration, and liquid-to-gas ratio. Monroe Environmental is one example of an industry leader whose packed bed scrubbers are capable of 99.99% removal efficiency. XICHENG’s specific guaranteed performance will be provided based on your detailed process parameters during the project quotation stage.

The system includes an “automatic dosing system” with a pH online detector, metering pump, and mixing barrel. It continuously monitors the pH of the scrubbing liquid, and when it falls outside the optimal range (indicating NaOH depletion), the pump automatically injects fresh alkaline solution from the mixing barrel. This maintains consistent neutralization performance, prevents chemical overdosing, and significantly reduces operator workload.

The first step is to determine your total exhaust air volume in m³/h. Match this volume to the nearest model range in our Technical Specifications table. For example, an air volume of 6,000 m³/h would fall in the 5500-8000 range, corresponding to the 1200mm tower. If your acid mist concentration is unusually high, or if you require >99% removal, a multi-stage system or a larger model may be necessary. Our engineering team can provide a detailed sizing verification if you share your process data.

Our product page outlines a clear installation method. The basic steps are: 1) Secure the unit on a level, corrosion-resistant foundation. 2) Connect the front exhaust duct to the acid mist inlet. 3) Install the anticorrosive centrifugal fan at the rear, configured for induced-draft (negative pressure) operation to prevent leaks. 4) Install the chimney after the fan. 5) Connect the automated dosing system to the water tank. 6) Install the electrical control panel to manage the pump, fan, and dosing system. It is essential to ensure adequate clearance for inspection and maintenance.

A well-designed maintenance schedule prevents corrosion, scaling, and unexpected downtime. We recommend:
Weekly: Check spray nozzle patterns and verify pH probe calibration.
Monthly: Test and replace the scrubbing liquid as needed; inspect the dosing pump.
Quarterly: Inspect the mist eliminator for scaling or damage.
Annually: Perform a full packing inspection and replace any degraded media (typical service life is 3-5 years).
PP construction eliminates the need for constant corrosion monitoring, a major advantage over metal scrubbers. For a complete, tiered maintenance checklist, refer to our Acid Scrubber Maintenance Guide.

Low removal efficiency: Usually caused by depleted scrubbing liquid concentration or blocked spray nozzles.
High pressure drop: Indicates solids accumulation or scaling in the packing.
Liquid carryover: A sign of a damaged or saturated mist eliminator.
Pump cavitation or noise: Check for leaks in the suction line or a clogged strainer. Because the scrubber body is made of PP, you avoid the shell corrosion and pinhole leaks that are common failure points in metallic scrubbers.

With proper maintenance, the PP polypropylene housing can last 8–12 years in normal corrosive acid gas environments. The internal packing media will typically need replacement every 3–5 years, depending on the acid type, concentration, and operating hours. This significantly exceeds the service life of unlined metallic scrubbers, which can fail in 2-4 years under similar conditions. To learn how we tackle these challenges, read our guide on Acid Fume Scrubbers: Corrosion & Compliance Solved.

The neutralized scrubbing solution will contain dissolved salts (e.g., NaCl from the HCl + NaOH reaction). You must have, or plan for, a wastewater treatment system. Before discharge, the solution should be neutralized to a pH of 6-9 and cleared of any solids. Always verify compliance with your local wastewater regulations. For a more detailed discussion on this topic, please see our guide on scrubber water treatment.

Standard models typically ship within 15–25 working days from our factory in China. Custom configurations, including multi-stage systems or non-standard sizes, may require a longer production time. We ship via sea freight (FOB/CIF) to major ports worldwide.