Finished Projects

The aim of this research project was the scientific description and determination of the remobilization behavior of heavy metals previously retained on filter materials by various de-icing salts. These filter materials are used in decentralized treatment systems for traffic area runoff. Until now, a test specification is missing in the approval process of the German Centre of Competence for Construction (Deutsches Institut für Bautechnik), that can be used to completely investigate the remobilization behavior. Therefore, no decentralized treatment plant for road runoff is available, for which the filter stability considering all relevant de-icing salts is proven.

Gas production of a digestor at a wastewater treatment plant can be substantially increased by the addition of co-substrates, i.e. by co-treatment of biowastes. Depending on the kind and amount of co-substrate added, gas production can rise so strongly that it becomes possible for plants to become self-sufficient and operate without any external energy inputs. In times of rising energy prices, such increases in energy production are very desirable. Moreover, energy from renewable resources is generated, thereby contributing to climate protection.

The Bavarian Water Policy Adminsitration needs current data of costs concerning communal wastewater treatment plants and sewer system parts for example for giving gratuities. Therefore the Bayerische Landesamt für Umwelt delegated the Technische Universität München (TUM) with the raise and evaluation of specific investment costs and costs of redevelopment.

Due to an increasing amount of power generated from renewable resources in Germany, covering the fluctuating energy demand from industry and private households will become more and more challenging. Currently various available energy conversion and storage technologies (e.g. batteries, pump storage hydro power systems) are only applicable as short- or midterm storage due to limited capacity. In contrast, the gas grid has one of the largest long term storage capacities available. In this context the project aims to further study and develop the microbial generation of methane (as a storable gas) directly from hydrogen and carbon dioxide, which could be an efficient alternative to the well-known Sabatier reaction (chemical-catalytic process). The required hydrogen can be generated in times of excess power via electrolysis, the carbon dioxide streams could be used directly at their origin (e.g. industries, biogas plants). This research focusses especially on the investigation of flexible (on demand) and efficient operation of the microbial methanation process, being essential to be applied as a future energy conversion and storage technology.

The central theme of this project is to investigate the interrelationship of transport processes in flowing waters and the processes which occur within local biocenoses. More specifically, the interaction of pathogenic bacteria in the bulk phase, resulting from fecal contamination, and the benthic biofilm will be examined for the Isar River. The fundamental processes will be quantified through lab and field experiments. Finally, the results will be incorporated into a mathematical model for simulation of the fate and transport of indicator bacteria.

Water scarcity is one of the urgent problems in the 21st century and affects one of three persons on the globe. In this context, it is very important to seek for technologies capable of cleaning and eliminating persistent pollutants from water resources. The related environmental toll should be kept at a minimum, material and energetic costs should be reduced and the method has to be free of residues.

Nitrous oxide (N2O) can be emitted during the biological nitrogen removal as an undesired intermediate or side-product. With a greenhouse gas potential 298 times higher than that of carbon dioxide, its resistance time of 114 years in the atmosphere and its potential of ozone depletion, these emissions should be reduced as much as possible to mitigate their negative influence on the environment. However, nitrous oxide can also be used as an energy source. That is why this project does not only investigate the diverse biological N2O production pathways including reduction strategies during nitrogen removal processes, but also examines the intended production of nitrous oxide with coupled extraction processes for a beneficial recovery of nitrogen.

The Chair of Urban Water Systems Engineering is part of the project NeXus of Water, Food and Energy which is funded by the German Academic Exchange Service (DAAD). The project deals with the interaction and the influence of the limited resources of water, food and energy. TU Munich cooperates with the EuroTech-Universities Danish Technical University (DTU), the National Technical University of Athens (NTUA) and the Colorado School of Mines.

In collaboration with the Chair of Water Quality Control and Environmental Technology at Ruhr University of Bochum (RUB) and the company Dr. Pecher AG, a decentralized stormwater treatment system had been developed and modified for the retention of hydrocarbons and other organic trace materials from traffic area runoff.

Managed aquifer recharge (MAR) systems, such as riverbank filtration (RBF), soil aquifer treatment and artificial recharge and recovery, have been used for decades to improve the availability of localized water supplies by the utilization of less desirable water sources like storm water, impaired surface water and reclaimed water. During infiltration of water through the vadose and saturated zones, microbial degradation and assimilation is playing a dominant role for the attenuation of organic contaminants.

For the evaluation of the material load of traffic surface discharges in the technical sets of rules the average daily traffic volume is consulted. Recommendations for infiltration plants for traffic surface discharges are given according to the average daily traffic volume. This approach is questioned by the composition of literature data for expiration values of different traffic surface discharges. However, these literature data are not necessarily reliable. Because many boundary conditions, as for example sampling time and sampling mixes, are missing.