The results obtained in this study are encouraging and important for the implementation of permeable pavement and swales in The Netherlands, since the performance of SUDS in delta areas and in areas in the world with comparable hydraulic circumstances has been viewed with skepticism. The research undertaken on Dutch SUDS field installations has demonstrated with new, full scale monitoring methods that most of the bioretention swales and permeable pavements tested in this study meet the required hydraulic performance levels even after years in operation and without maintenance. Standardized tests of sedimentation devices however demonstrated that these facilities have a limited effectiveness for particles smaller than 60 µm while receiving a normal hydraulic loading. The applied methods of full scale testing of SUDS can easily be applied to observe the hydraulic performance of swales and permeable pavement after years of operation. Innovative monitoring methods and visualization of these experiments using video footage allows real-time observation of the entire infiltration process. Recording these observations in a logbook can provide insight in their demand of maintenance and can also help to improve their design.
MULTIFILE
A local operating theater ventilation device to specifically ventilate the wound area has been developed and investigated. The ventilation device is combined with a blanket which lies over the patient during the operation. Two configurations were studied: Configuration 1 where HEPA-filtered air was supplied around and parallel to the wound area and Configuration 2 where HEPA-filtered air was supplied from the top surface of the blanket, perpendicular to the wound area. A similar approach is investigated in parallel for an instrument table. The objective of the study was to verify the effectiveness of the local device. Prototype solutions developed were studied experimentally (laboratory) and numerically (CFD) in a simplified setup, followed by experimental assessment in a full scale mock-up. Isothermal as well as non-isothermal conditions were analyzed. Particle concentrations obtained in proposed solutions were compared to the concentration without local ventilation. The analysis procedure followed current national guidelines for the assessment of operating theater ventilation systems, which focus on small particles (<10 mm). The results show that the local system can provide better air quality conditions near the wound area compared to a theoretical mixing situation (proof-of-principle). It cannot yet replace the standard unidirectional downflow systems as found for ultraclean operating theater conditions. It does, however, show potential for application in temporary and emergency operating theaters
The application of sensors in water technology is a crucial step to provide broader, more efficient and circular systems. Among the different technologies used in this field, ultrasound-based systems are widely used, basically to generate energy peaks for cell lysis and particle separation. In this work, we propose the adaptation of an ultrasound system to monitor the concentration of solid particles in wastewater treatment plants settlers as well as to indicate sludge level (real time). A similar sensor was developed and tested in another project which operated successfully at solids concentration up to 1% in UASB reactors. Such measurements are nowadays obtained via time-consuming physical (solids) analysis, which can compromise the efficiency of the settlers and the quality of the effluent. The present project proposes an improved version of the sensor, which will combine solids concentration monitoring and sludge level detection. The defined targets have the intention to make a sensor with a much broader range of applications, been suitable not only for UASB reactors but also to settler and aerobic tanks. The project is a cooperation between the Water Technology lectoraat of NHL Stenden University of Applied Sciences, two SME’s - YNOVIO B.V. and Lamp-ion B.V. - and the INCT group (Brazil). If proven feasible, the concept can generate a big business market to the involved Dutch partners as well as favor the automation of WWTP in the Netherlands, Brazil and around the world.
