When surfactants enter a wastewater air stripper, stable foam can increase liquid holdup, raise pressure drop, reduce operating range, overload the demister, and disturb mass transfer. Water chemistry, upstream source control, airflow, packing openness, anti-foam effects, and pretreatment should be reviewed before replacing packing or increasing blower capacity.

When a scrubber meets its gas-removal target but the downstream fan corrodes, investigate mist carryover, demister velocity, wall bypass, drainage, packing entrainment, downstream condensation, and deposit chemistry. Gas-phase removal efficiency and liquid-droplet control are separate performance requirements.

When an HF scrubber uses calcium-containing hard water, fluoride absorption can create a precipitation and scaling risk even if the packing material itself is fully compatible. Makeup-water hardness, local chemistry, evaporation, blowdown, distributor opening size, packing openness, demister deposits, and scale analysis should be reviewed together.

In ammonia-water packed absorbers, strong absorption can create a temperature bulge that reduces ammonia solubility and limits further removal. Bed height, water rate, inlet temperature, heat of absorption, intercooling, liquid properties, hydraulic loading, and cooling-failure scenarios should be evaluated as one integrated duty.

When chlorosilane-containing exhaust enters a wet scrubber, hydrolysis can generate acidic liquid and silica-type solids or gels inside the treatment system. Packing openness, quench staging, solids removal, distributor opening size, support drainage, demister washing, material compatibility, and deposit-cleaning strategy should be evaluated together.