Exhaust air purification for battery test stations

Battery tests under real-world testing conditions generate hot exhaust gases, some of which are unburned, and these must be reliably cleaned before they can be released into the atmosphere. For an automotive manufacturer’s battery test rigs, PlasmaAir AG built a system to treat exhaust air flows of up to 45,000 Nm³/h at temperatures of up to 400°C, with the aim of reliably complying with the limits set out in TA Luft.

INITIAL SITUATION

During battery testing, hot exhaust gases containing unburnt, partially combusted and fully combusted constituents are produced under full load. This exhaust air must be safely extracted and treated to ensure compliance with statutory emission limits, even when volume flows are high and fluctuate and temperatures are elevated.

OUR SOLUTION

PlasmaAir AG has developed a multi-stage wet scrubber system:

A Venturi scrubber with a shared water reservoir provides flexibility under varying operating conditions and flow rates.

An upstream spray section (quench) cools the hot exhaust air to the cooling limit temperature before it enters the Venturi scrubbers.
Dust and acidic gaseous pollutants are reliably removed in pH-stabilised wash water operated under alkaline conditions.
Downstream dry filters, which can be cleaned using compressed air, remove residual dust.
Activated carbon filters bind odorous substances and longer-chain hydrocarbons in the final purification stage.
The purified exhaust air is discharged outdoors through a 25 m-high steel stack, with continuous VOC monitoring.
The system can optionally be expanded with a bypass circuit for dust discharge and, if required, a post-combustion stage for gases that cannot be removed, such as hydrogen and methane.