Water and waste water technology

Industrial process water

Systems for the treatment of industrial waste and process water, tailored to specific requirements – Fraunhofer IKTS provides support in the development of suitable strategies for closing cycles and recovering reusable materials.

Eine Person mit Schutzbrille und Kittel steht vor einem Membranteststand und betrachtet eine grüne Flüssigkeit in einem Behälter.
© Fraunhofer IKTS
Membrane test stand.

Solvent cleaning


Manufacturing processes in the chemical and pharmaceutical industries may produce contaminated organic solvents which need to be cleaned before any re-use. Also, the recovery of homogeneous catalysts is garnering more interest due to the scarcity and soaring price of precious metals. Both processes are currently performed using distillation. However, since they also result in high energy costs, ecological and economically viable alternatives are in high demand.

One alternative or supplementary process may be a filtration stage with organophile nanofiltration membranes. This enables recovering a large part of the reusable materials in a pressure-driven physical process, which thus does not require any external heating or cooling energy. Thanks to their stability in organic solvents, ceramic membranes are well-suited as the basis for developing such processes. One strength of Fraunhofer IKTS is the capability to develop and modify specific membranes individually for each client.


  • Energy-efficient alternative for cristallization and rectification
  • No replacement of phases required
  • Significantly reduced side and decomposing reactions (lower thermal load)
  • No additives used
  • High chemical and thermal resistance of the ceramic membranes
© Fraunhofer IKTS
Filtration module with ceramic membranes.

Recycling of alkaline solutions


The efficiency of any industrial cleaning stage is also dependent on the purity of the actual medium used. It makes sense, therefore, to separate the impurities absorbed by the cleaning agent so as to maintain the cleaning effect. One of the most important cleaning media in the industry, used above all in the foodstuff and beverage industry, is hot alkaline solution. The cleaning of alkaline solutions involves the removal of contamination such as paint, CSB and particles, but also carbonates that have formed. The process stage proposed here can help enhance the recycling of alkaline solutions and minimize the usage of additives.

On account of the challenging chemical and thermal requirements, ceramic membranes perform better than polymer membranes. Beyond this, ceramic membranes allow for more compact plants as they yield a better filtration performance than polymer membranes in relation to the filtration area. Fraunhofer IKTS provides client-specific membrane development and modification.


  • Reduction of fresh alkaline solution and savings on additives
  • Minimizing carryover into downstream process stages
  • Increased membrane service life if ceramic membranes are used
  • Potentially minimized area usage (compared to polymer membranes) if using ceramic membranes
In einem Labor ist im Vordergrund Elektrochemische Gewinnung von Selten-Erd-Verbindungen aus Displayfolien zu erkennen und im Hintergrund
© Fraunhofer IKTS
Electrochemical production of rare earth compounds from display cover sheets.

Recovery of reusable materials


We use our comprehensive technological capabilities and experience to develop processes for recovering reusable materials from waste water and liquid process media, as well as from secondary and non-conventional raw material sources. Fraunhofer IKTS is able to cover the full wet chemical process chain, starting with the extraction (leaching) from solids, to enriching using membrane-supported extraction processes, through to the pure metal or target product. In this regard, electrochemical processes are preferred, but combinations of processes including extraction processes are also used. The corresponding chemical recovery and waste water treatment are of course also part of the IKTS portfolio.

Fraunhofer IKTS has extensive experience in recovering rare earth concentrate from secondary raw material sources, preparing rare earth compounds in a pure state, as well as in recovering special and precious metals (indium, gallium, tellurium, silver, palladium, platinum, rhodium) from scrap metal and dump materials. Hypolimnic water is one non-conventional source, allowing the extraction of many important raw materials, depending on the specific site.


  • Comprehensive technological know-how on membrane and electrochemical processes
  • Wide range of experience in terms of chemistry and materials (rare earths, special metals, precious metals)
  • Pilot and research facility for process development and optimization, available at short notice
© Fraunhofer IKTS
Laboratory test stand for C-14 total oxidation.

Treatment of radioactive waste water


Radioactively contaminated waste water is a byproduct in many sectors of the industry. It needs to be treated to prevent radioactive substances from being released into the environment. To be able to treat liquid organic waste containing C-14, which is notoriously difficult to handle, Fraunhofer IKTS has further developed a process for electrochemical total oxidation. It is a relatively simple process which allows transforming the radioactive carbon (C-14) that is bound within the organic substances into alkaline earth metal carbonates suitable for ultimate disposal.

The electrochemical total oxidation process is also suited for the removal of many other highly persistent organic contaminants, for instance carcinogenic compounds, such as nitroaromatics or endocrine substances. If correctly designed and planned, the process is superior to all currently established options in terms of cleaning performance. The recovery of certain raw materials (rare earths, niobium/tantalum, coltan and others) and the use of geothermal sources for heat generation also result in enriched natural radionuclides of the radioactive uranium and thorium series, which can be separated in suitable electrochemical processes.


  • Easy production of C-14 carbonates that are suited for ultimate disposal
  • Treatment of ignitable and/or aggressive organic waste materials
  • Application for a wide range of substances
  • Efficient separation of geogenous nuclides using electrochemical processes
© Fraunhofer IKTS
Radio sensor node for plant monitoring.

Plant monitoring


The term plant monitoring describes the competent and professional evaluation of a plant and its components with regard to its operative behavior. It is the basis for optimizing processes and serves to identify operative problems and their solutions. The research facilities developed, built and used by Fraunhofer IKTS provide all the options for process development and optimization – from »proof of principle« up to pilot testing.

Applied sensor systems permit the early identification of defects and material-related fatigue during plant operation. The condition monitoring of pipelines, tanks and many other production processes increases the availability and safety of the plant, contributing significantly to reduced operating costs.


  • Diagnostically supported basic engineering, such as dimensioning and design of heat exchangers, pumps etc.
  • CFD-supported development of components (e. g. modules, casings, heat exchangers, etc.)
  • Long-term monitoring of processes with the help of pilot plants (lab and/or field setup)
  • Increased plant availability and safety through condition monitoring