Deodorization at waste water treatment plants - Case Study
The presence of microorganisms in wastewater causes a decrease in dissolved oxygen levels due consumption by the organisms’ metabolic processes. The more microorganisms there are, the greater the biological demand for oxygen. When this demand exceeds that which can be provided by the exchange of air, an anaerobic process begins, thus creating a reducing environment that favours the release of odour-causing compounds at the WWTP:
- Sulphur derivative (H2S and mercaptans)
- Nitrogen derivatives (NH3 and amines)
- Acid derivatives (acetic)
- Aldehyde, ketone and ester derivatives
For these reasons, it is vital to seek solutions to the problem of bad odours and implement deodorising treatments.
Bioconservacion and the Besós waste water treatment plant (WWTP), managed by Aguas de Barcelona, have reached a collaboration agreement to carry out various field tests on new products.
The agreement allows Bioconservacion to use the Besós facilities to carry out testing of new filtration media to deodorise the air.
The Besós WWTP is currently using Bioconservacion’s filtration media in several equipments, Side Acces-type that are used to deodorise certain parts of the plant. A first stage with Bi-On carb OX is being used along with a second stage with Bion +/AC blend (a material that will continue to be provided on a regular basis). Over the last year, Bioconservacion has developed the Bi-On carb ODR filtration media - a new carbon-based filtration media with a high capacity for removing H2S and with mechanical properties.
Thus, it is proposed that stability tests be conducted on the Bi-On carb ODR filtration media within equipment where extreme conditions exist compared to those where the media is to be tested. We therefore aim to:
- Test the Bi-On carb ODR filtration media in saturation conditions.
- Assess the critical parameters (operating time, conditions, etc) that cause a loss of mechanical properties within the Bi-On carb ODR product.
Bioconservacion’s technical staff will carry out regular extensive monitoring of different variables in order to achieve robust characterisation of the installation and to be able to draw as meaningful conclusions as possible. The variables that will be monitored are the following:
- Humidity and temperature coming in and between sections of the equipment.
- Concentration of incoming and outgoing H2S/total VOCs to/from the equipment.
- Loss of load within the different stages of the equipment.
- Rate of flow coming into the equipment.
With the results obtained, comprehensive research will be conducted to assess whether it is possible to improve the functioning of this type of equipment.