Street sewer filterStop odour emissions from all common sewer manholesTo the product
Street drain filterFilter malodorous gases while simultaneously permitting street water drainage.To the product
AquastopPrevents inflow into the sewer systemTo the product
Multi-chamber filterHeavy-duty solution in areas with severe odour nuisancesTo the product
VolumenmaxEffectively eliminates particularly severe odour nuisancesTo the product
PolylokEnd-of-pipe filters for normal odour nuisances for direct use on vent pipesTo the product

Leading supplier of system solutionsfor exhaust air and extraneous water problems

Fritzmeier Umwelttechnik brings together expertise in plastics manufacturing and bacterial fermentation. Arising from this synergy, the COALSI brand was incorporated into the company in 2010. The original filter technology has been further developed to today's hybrid activated carbon filter with triple filtration. The COALSI system solution combines physical, chemical and biological methods which means that only harmless, almost imperceptible substances can pass through. Products for rainwater retention in foul or combined drainage systems complete the range.

Linking society and the waste disposal sector, we can provide the optimum solution for your needs. Operating simply, our solutions provide a quick and straightforward remedy, minimising health risks and avoiding costly remediation work. You can count on us!


We opted for a COALSI multi-chamber filter because its compactness and unobtrusive shape made it easy to integrate into the station. The hybrid filter mat technology reliably combats odours and is easy to maintain with a quick filter change. It has so far proven completely effective.

Hamburger Stadtentwässerung

COALSI enabled a structurally simple modification to the exhaust air system which, thanks to the filter technology used, has so far proven effective.

Emder Abwasser Technik