Biological Wastewater Treatment

Thanks to our comprehensive portfolio of biological, aerobic and anaerobic wastewater treatment processes, we can tailor each plant precisely to the individual conditions of our customers. This enables us to develop tailor-made, high-performance and resource-efficient solutions for sustainable industrial wastewater treatment.

Our biological processes are used successfully worldwide in the chemical and pharmaceutical industries, semiconductor production and in the energy sector. They have also proven themselves in the pulp and paper industry, in laundries and textile production as well as in food processing and agriculture. Wherever high organic loads need to be reduced safely, economically and in an environmentally friendly manner, biological processes offer the optimum solution.

In the biological treatment of wastewater, a distinction is made between two main types of processes: the aerobic and the anerobic process. The distinction is very simple. While the use of oxygen is necessary for aerobic wastewater treatment, this is not required for the anerobic process.

Both variants have some clear advantages and disadvantages, which must be taken into account depending on customer requirements. While aerobic treatment usually results in less odor nuisance and nutrient removal is often more effective, oxygen enrichment and the disposal of biomass can result in significantly higher overall energy consumption and increased operating and maintenance costs.

Anerobic wastewater treatment processes are often cheaper and more flexible, and the biogas produced can be used as a source of renewable energy. However, it is not uncommon for both wastewater treatment processes to be used in one wastewater treatment plant in order to ensure energy and cost-efficient treatment in compliance with the respective regulatory requirements for discharge.

The thickness and composition of the biofilm on the carrier material are influenced both by the shear forces prevailing in the bioreactor and by the substances contained in the wastewater: the higher the content of organic substances in the wastewater, the faster the biofilm grows. Activated sludge processes have the disadvantage that when excess sludge is removed, some of the microorganisms present in suspension are also regularly removed.

Despite the return of recirculation sludge from secondary clarification, the microorganisms only reach a relatively short age overall. In the MBBR process, the immobilized microorganisms on the carriers can have a much longer lifespan. This allows microorganisms to establish themselves in the biofilm that have specialized in compounds that are difficult to degrade but have very long generation times. Overall, the stability of the purification process is higher than in activated sludge systems, and load peaks are better absorbed.

DAS Environmental Expert GmbH uses a carrier material that has a very high specific surface area and therefore enables particularly compact MBBR bioreactors. The shape of the packing also reliably prevents the carrier material from blocking and achieves a consistently high degradation rate. Our MBBR systems can be designed as compact systems or as modular bioreactors. The modular reactors require significantly less space than conventional activated sludge plants. There is no need for civil engineering work. With the appropriate process engineering design, our MBBR can even be designed and operated as a denitrification reactor.