Periodic Reporting for period 1 - SuspensionFlow (Development of a biomimetic prototype to reduce microplastics emissions)
Período documentado: 2024-06-01 hasta 2025-11-30
The SuspensionFlow project aimed to develop a biomimetic filtration solution to reduce microplastic emissions from domestic washing machines by transferring biological filtration principles into an industrially relevant technical application. The focus was on ram-feeding fish, whose gill structures operate according to cross-flow filtration principles that are inherently resistant to clogging and therefore well suited for fibre-rich suspensions such as washing machine effluents. This project is an advancement of a previous project which studied the biological principles underlying this specific filtration type and in which we developed a first option for a filter element. In the SuspensionFlow project presented here, we developed the underlying principle into a scalable filtration unit with higher filtration rate and we undertook IP activities.
First, we tested a whole range of particle types in different testing setups in order to develop a system which can filter more diverse particle shapes compared to the initial filter design. Computational fluid dynamics simulations and flow-channel experiments were combined to analyse flow patterns, particle trajectories, and filtration efficiency. This work led to the identification of several biomimetic filter structures achieving more than 80% microplastic retention, while avoiding rapid clogging. Subsequently, the most efficient biological principles were abstracted and optimised for industrial application and we tested this system, together with regular self-cleaning intervalls, under washing-machine-relevant conditions using fibres and particles representative of real laundry effluents. The biomimetic filters demonstrated stable volume flow, effective self-cleaning, and high retention efficiency, while outperforming conventional dead-end filters in terms of clogging resistance. A functional demonstrator and laboratory test stand was realised. We also explored biological solutions for aerosol filtration in order to identify mesh types and inlet shapes which might be beneficial for different filter shapes and particle sizes. As aerosol filtration happens under very different conditions compared to fluid filtration, this work is not yet finished but looks promising to advance the filter even more.
In the final phase, intellectual property, exploitation potential, and societal relevance were addressed. A German patent application covering the biomimetic filter element and filtration method was filed earlier and we entered discussions with the German patent office regarding the advancments made within the PoC. Market potential was identified as high due to increasing regulatory pressure and the significant contribution of synthetic textiles to global microplastic pollution. In addition, two publications resulted from this project.
Overall, the project delivered a validated, biomimetic filtration concept with strong potential for further industrial development and commercialization, contributing directly to the reduction of microplastic emissions and to European sustainability and zero-pollution objectives.
First, we tested a whole range of particle types in different testing setups in order to develop a system which can filter more diverse particle shapes compared to the initial filter design. Computational fluid dynamics simulations and flow-channel experiments were combined to analyse flow patterns, particle trajectories, and filtration efficiency. This work led to the identification of several biomimetic filter structures achieving more than 80% microplastic retention, while avoiding rapid clogging. Subsequently, the most efficient biological principles were abstracted and optimised for industrial application and we tested this system, together with regular self-cleaning intervalls, under washing-machine-relevant conditions using fibres and particles representative of real laundry effluents. The biomimetic filters demonstrated stable volume flow, effective self-cleaning, and high retention efficiency, while outperforming conventional dead-end filters in terms of clogging resistance. A functional demonstrator and laboratory test stand was realised. We also explored biological solutions for aerosol filtration in order to identify mesh types and inlet shapes which might be beneficial for different filter shapes and particle sizes. As aerosol filtration happens under very different conditions compared to fluid filtration, this work is not yet finished but looks promising to advance the filter even more.
In the final phase, intellectual property, exploitation potential, and societal relevance were addressed. A German patent application covering the biomimetic filter element and filtration method was filed earlier and we entered discussions with the German patent office regarding the advancments made within the PoC. Market potential was identified as high due to increasing regulatory pressure and the significant contribution of synthetic textiles to global microplastic pollution. In addition, two publications resulted from this project.
Overall, the project delivered a validated, biomimetic filtration concept with strong potential for further industrial development and commercialization, contributing directly to the reduction of microplastic emissions and to European sustainability and zero-pollution objectives.
The SuspensionFlow project successfully developed and validated a novel biomimetic filtration concept to reduce microplastic emissions from domestic washing machines. By systematically analysing ram-feeding fish, the project translated biological cross-flow filtration principles into technically feasible filter designs suitable for fibre-rich washing machine effluents.
A major achievement was the creation of a parametric, biology-based design framework derived from quantified fish gill morphology. This enabled the development of multiple fish-like filter geometries, which were evaluated through combined CFD simulations and flow-channel experiments. Several filter structures achieved microplastic retention efficiencies exceeding 80% while avoiding rapid clogging and we tested this for different particle shapes.
The project further advanced the state of the art by implementing a semi-cross-flow filtration system with periodic, automated self-cleaning inspired by fish opercular flow. Integrated into a modular filter module, this concept demonstrated stable volume flow and high retention under washing-machine-relevant conditions and outperformed conventional dead-end filters in terms of clogging resistance.
In addition to technical validation, the project delivered a functional demonstrator, industry-aligned test infrastructure, and a German patent application protecting the core innovation. Overall, this project established a scientifically validated and industrially relevant biomimetic solution with strong potential for commercialization and significant impact on reducing microplastic pollution.
A major achievement was the creation of a parametric, biology-based design framework derived from quantified fish gill morphology. This enabled the development of multiple fish-like filter geometries, which were evaluated through combined CFD simulations and flow-channel experiments. Several filter structures achieved microplastic retention efficiencies exceeding 80% while avoiding rapid clogging and we tested this for different particle shapes.
The project further advanced the state of the art by implementing a semi-cross-flow filtration system with periodic, automated self-cleaning inspired by fish opercular flow. Integrated into a modular filter module, this concept demonstrated stable volume flow and high retention under washing-machine-relevant conditions and outperformed conventional dead-end filters in terms of clogging resistance.
In addition to technical validation, the project delivered a functional demonstrator, industry-aligned test infrastructure, and a German patent application protecting the core innovation. Overall, this project established a scientifically validated and industrially relevant biomimetic solution with strong potential for commercialization and significant impact on reducing microplastic pollution.
Semi-cross-flow filtration with self-cleaning
State-of-the-art washing machine filters are predominantly dead-end filters, which suffer from rapid clogging and require frequent manual cleaning. SuspensionFlow introduces a semi-cross-flow filtration concept with periodic, automated cleaning, inspired by fish opercular flow. This enables continuous operation under high fibre loads without permanent blockage.
High retention efficiency combined with clogging resistance
Existing bio-inspired concepts reported in the literature typically achieve moderate retention rates (often <70%) or lack validation with textile fibres. The filter module demonstrated >80% microplastic fibre retention while maintaining stable volume flow and avoiding clogging—an unprecedented combination for washing-machine-scale filters.
Parametric, biologically grounded filter design methodology
Beyond individual prototypes, the project delivered a systematic, parametric design framework derived from quantified fish gill morphology. This allows controlled variation of key parameters (angle of attack, filter length, open area, mesh size) and represents a step beyond trial-and-error design approaches used in existing filter developments.
Demonstration under application-relevant conditions
Unlike most bio-inspired filtration studies, which remain at laboratory proof-of-principle level, SuspensionFlow validated its concepts in flow conditions comparable to washing machine hoses, including realistic flow rates, pressures, and fibre types. This significantly advances the technology readiness toward industrial implementation.
Protectable intellectual property with industrial relevance
The resulting biomimetic filter concept was novel enough to support a patent application, indicating clear differentiation from existing cross-flow, cross-step, and ricochet filtration technologies.
State-of-the-art washing machine filters are predominantly dead-end filters, which suffer from rapid clogging and require frequent manual cleaning. SuspensionFlow introduces a semi-cross-flow filtration concept with periodic, automated cleaning, inspired by fish opercular flow. This enables continuous operation under high fibre loads without permanent blockage.
High retention efficiency combined with clogging resistance
Existing bio-inspired concepts reported in the literature typically achieve moderate retention rates (often <70%) or lack validation with textile fibres. The filter module demonstrated >80% microplastic fibre retention while maintaining stable volume flow and avoiding clogging—an unprecedented combination for washing-machine-scale filters.
Parametric, biologically grounded filter design methodology
Beyond individual prototypes, the project delivered a systematic, parametric design framework derived from quantified fish gill morphology. This allows controlled variation of key parameters (angle of attack, filter length, open area, mesh size) and represents a step beyond trial-and-error design approaches used in existing filter developments.
Demonstration under application-relevant conditions
Unlike most bio-inspired filtration studies, which remain at laboratory proof-of-principle level, SuspensionFlow validated its concepts in flow conditions comparable to washing machine hoses, including realistic flow rates, pressures, and fibre types. This significantly advances the technology readiness toward industrial implementation.
Protectable intellectual property with industrial relevance
The resulting biomimetic filter concept was novel enough to support a patent application, indicating clear differentiation from existing cross-flow, cross-step, and ricochet filtration technologies.