One of the leading Mexican paper and cardboard packaging producers installs one C-MEM WWTP (173 m³/d, 2 modules, 128 cartridges) with downstreams reverse osmosis each in two of its subsidiaries i.e. in Mexicali and Monterrey for treating the wastewater from paper and cardboard production. First, the wastewater is treated biologically with the C-MEM ultrafiltration technology and then cleaned to recycling quality by the downstreams RO, which reduces the water consumption drastically, as the paper and cardboard production process requires relatively much water.
Beside remainders of fibres wastewaters from paper production also contain substances like de-inking-chemicals, bleaching agents, process chemicals as well as additives and are characterized by a high chemical oxygen demand (COD). As the C-MEM technology practically effects complete containment of all microorganisms, the biomass can be kept at much higher concentrations and the MBR operated with significantly higher sludge age, which enables advanced elimination of hardly degradable organic compounds e.g. COD.