H2S Odours Eliminated with ZABOCS® System

A compact odour control solution that eliminated acclimation time with the ability to operated in extremely cold weather conditions.

A town located in the Western Canadian Rockies prides itself on its snatural features which includes a mountain-fed stream flowing through the middle of town. The river and its valley provide wildlife habitat, scenic trails and drinking water for the town’s residents. In 2014, after expansion of the town's 10 million liter per day (MLD) wastewater treatment plant, there was an increase in H2S odours near one of a popular riverwalk trail.  The town's municipal district took quick action to evaluate a solution to remediate it.

The town and its water management contractor faced a challenge common to many facilities which was lack of land space. Also, the cold temperatures during the Canadian winters was another barrier which is typical to many wastewater treatmetn facilities in northern latitudes. 

During the evaluation of a solution, the town and contractor preferred a biofiltration odor control removal systems, however the running of water would be a requirment for operation.  Also, the system would need to be installed in a climate controlled location to operate properly year-round when temperatures could reach -18°C (0°F).  Due to the climate and footprint concerns, a proposed system based on an in-ground tank was also evaluated, however rejected with the town continuing to look for an alternative solution.


After further evaluation of technologies it was determined that the ZABOCS® Biological Odor Control system from Evoqua Water Technologies would be an ideal solution to meet year-round operational requirements and space constraints, The ZABOCS system, a zero acclimation biological odour control process is a multi-media system that combines gas absorption, adsorption and biological treatment for capturing and elimination of organic and inorganic odours from wastewater process air streams. The ZABOCS system combines biological and carbon media processes allowing for odour control treatment three times the air volume compared to similar sized conventional biofilter systems. A primary biological stage removes most of the H2S odours, and a secondary polishing stage uses carbon to boost efficiency and provide extra capacity to handle spikes in H2S volume. In addition, the second stage provides odour removal instantly at start-up while the biofiltration stage is acclimating.

The ZABOCS system was delivered as a single package unit with a compact footprint to easily meet space requirments. The unit was also installed in a weatherproof enclosure, assuring continuous operation year-round.  Evoqua Water Technolgies provided engineering for this system and ongoing service as needed. 

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The installation of the ZABOCS® system has provided 99.9% removal of H2S odours and over 99% of odour from the foul air stream, providing a pristine recreational and esthetic environment for the users of nearby homes, parks and hiking trails.

Evoqua’s advanced ZABOCS system technology helped the town eliminate treatment plant odour problems in a compact footprint with a solution that eliminated acclimation time and could operate in extreme cold.
The ZABOCS system meets the local odour removal requirements and has extra filtration capacity to support future growth, assuring a pristine recreational environment for residents to enjoy for generations to come.