Plastic microparticles in water are becoming an increasingly serious problem in the environment. The Fraunhofer Silicon Photovoltaic Center and its partners have jointly developed a new filtration system that can monitor lakes and rivers more quickly and easily. With the support of the Research Institute (BAM), the goal of the research project is to establish a database to analyze the pollution of lakes and rivers and to manage pollution.
Photomicrograph of a prototype silicon filter with a 50 μm aperture laser micromachining (Fraunhofer CSP)
Optical micrograph of a prototype silicon filter after laser micromachining with a pore size of approximately 50 μm (Fraunhofer CSP).
The invasion of ecosystems by plastic particles has become an increasingly serious environmental problem. The current pathways for these particles to enter lakes, rivers and wastewater are not fully understood. Furthermore, there is no suitable standardized method for studying and detecting plastic particles in water. However, A reliable scientific database of the origin, impact and impact of plastic particles in the environment is critical to solving environmental problems.
A research project initiated by the German Federation 'Representative diagnostic strategy for integrated systems to understand the specific plastic entrainment into the environment (RUSEKU)'. The goal of the Institute for Materials Research and Testing (BAM) is to develop a diagnostic method by 2021 to enable faster, more standard measurement of particle entrainment in lakes and rivers. It will also allow identification of locations where water micro-plastic particles are particularly contaminated.
Fast standardized measurement
As part of the joint research project, the Fraunhofer Silicon Photonics Center CSP is working with SmartMembranes GmbH to develop a special filtration system as part of a standardized and simple sampling method. The cascade filtration system will use a special silicon filter with defined pore density and size to capture plastic particles.
'Sampling methods are key factors in obtaining reliable conclusions about the microplastic volume of groundwater, drinking water and wastewater or surface waters. Plan to use a sampling scheme to make a significant contribution to this, 'Christian Hagendorf, responsible for the research project at Fraunhofer CSP 'The laser and chemical etching process will be used to make the appropriate hole size on the silicon substrate, where the particles will be retained on the silicon substrate. In the later analysis of the laboratory, we will use the width in the transmission method. The chemical composition of transparent silicon in the wavelength range of infrared light, and the spectral measurement technology can see the microplastic particles located on it, 'Hagendorf added.
Application optimization filter system
Another important parameter affecting the quality of the filter is the mechanical strength of the filter. The mechanical strength of the filter is to carry the load caused by the water flow during the sampling process without breaking. In addition, the filter needs to be intelligent, optimized for hole geometry and surface finish. Another goal of this work is to define the working procedure from sampling to cleaning until the analysis of microplastic particles with the partner. This 'smart sampling' should Make micro-plastic testing - from sampling to rapid analysis - to get a good adjustment.
This effective and reliable micro-plastic sampling method will lay a good foundation for strategies and measures to reduce micro-plastics in the water cycle. The joint research project is funded by the Federal Ministry of Education and Research (BMBF) as part of the 'Plastics in the Environment' research project. In addition to the Fraunhofer CSP, there are six research institutes and three SMEs involved in the project.
About Silicon Photovoltaic Fraunhofer CSP Center
Fraunhofer CSP is engaged in the application of silicon crystallization, solar module technology and solar wafer production. The institute develops new technologies from ingot production to module production, and also participates in the development of new materials in the value-added chain. The research focuses on the evaluation of solar cells and modules, as well as the characterization of electrical, optical and microstructured materials and components. The Fraunhofer CSP is a joint research institute of the Fraunhofer Institute for Microstructure and Systems IMWS and the Fraunhofer Solar System Institute ISE.
SmartMembranes Company Profile
SmartMembranes GmbH is a branch of the Fraunhofer Institute for Microstructures and Systems IMWS, which was founded in 2009 at Halle (Saale River). The company describes itself as the world's leading manufacturer of high-order porous materials for alumina and silicon. The high-order porous material has clear tunable membrane properties and structural parameters and is suitable for many innovative applications. In addition to producing materials according to customer specifications, another major pillar of the company's business is the development of new processes and products around the core business.