Fungal processes

When bacteria is not enough

Some compounds, such as antibiotics, are poisonous to prokaryotic organisms like bacteria but may be quite harmless to eukaryotic organisms like fungi. In cases where a wastewater is found to be toxic to bacteria, the use of microfungi can represent an efficient biological treatment alternative.

Microfungi grow as long threads called hyphae. In an activated sludge process this would cause problems with sludge recycling because of sludge bulking. However, in a suspended biofilm process no sludge settling and recycling is required and the fungi can grow and be retained within the treatment system.

Established technology

The full-scale plants that AnoxKaldnes has designed to date for pharmaceutical wastewaters are based on one or several MBBR™ biofilm stages where microfungi detoxify the wastewater and, at the same time, reduce a significant part of the COD. Subsequent MBBR™ biofilm stages are operated to promote the growth of bacteria that consume the remaining COD.

The use of microfungi is by no means restricted for use in the pharmaceutical industry. In chemical and even the food industry wastewaters (e.g. coffee and olive oil production), there are compounds that are very toxic to bacteria but still good food for microfungi.