Project:
Upgrade of existing WWTP by installation of an upstream high-loaded stage operated with Mutag BioChip™ carriers.
Industry:
Industrial effluent – specialty paper production.
Facts & figures:
Task:
Due to the closing of water circuits and switching from potato starch to grain starch for paper production, the incoming loads entering the existing low-loaded 2-staged biofilter (operated with 60.5 m3 Mutag BioChip™ since 2015) increased from orginally 180/400 mg/l BOD/COD to 300/750 mg/l BOD/COD. As the discharge limit values to the receiving water body, Lachte river, remained unchanged at 16/64 mg/l BOD/COD, an upgrade of the WWTP was required, as the existing low-loaded stage alone was no longer able to attain the effluent limits.
Solution:
By installing an additional MBBR stage as a high-loaded stage, filled with 335 m3 Mutag BioChip™, the incoming loads could be reduced to 50/100 mg/l BOD/COD, so that the existing biofilter can easily achieve the permissible discharge values again. Due to the addition of flotation effluent, the actual loads entering the biofilters are now even slightly higher than the design values, whereas the effluent concentrations are still being met reliably.
Results:
Due to an increase of influent concentrations at otherwise unchanged effluent limits, an upgrade of the existing WWTP at the specialty paper factory was performed. This was realized by the installation of an additional high-loaded stage, upstream of the existing low-loaded stage, whereas both stages are operated with Mutag BioChip™ carriers and the effluent concentrations are being safely attained again all the time. Practice showed that the plant is even able to perform at higher influent concentrations than originally designed for, whereas the effluent concentrations are still being met reliably.
Read our latest stories and subscribe for more.
