After finishing secondary school in 2002 in Sindelfingen, he served a civilian service at a school for mentally handicapped children. In October 2003 he started studying mechanical engineering at the University of Karlsruhe. Within the scope of the GEARE-programm (Global Engineering Alliance for Research and Education) he accomplished an academic year at the Purdue-University in Indiana, USA. The overall focus of his studies was the field of energy technologies. Daniel Winter concluded his studies in 2009 with the diploma thesis "Dimensioning and optimization of a solar driven desalination system by means of simulation" at the Fraunhofer ISE in Freiburg.
Since May 2009 he has continued to work in the workgroup "local water treatment" at the ISE. This team developes solarthermal driven desalination systems to allow a sustainable and local drinking water supply in arid areas lacking in infrastructure. Membrane distillation (MD), a thermal driven membrane process, seems well applicable due to the required temperatur level of 50-90°C and the robustness of the relevant membranes. The focus of Daniel Winters work is the characterization, simulation and optimization of the MD-modules that are developed and fabricated at the ISE and used in demonstration plants.
However, the potential to scale up the systems based on the actual module design is limited and almost exhausted. An increase in desalination capacity is essential to meet the growing demand on higher plant capacities required for e.g. efficient waste heat utilization from concentrated solar power plants and water supply of villages.
Short description of the doctoral thesis:
"Design of a solarthermal driven desalination system based on membrane distillation: Module design and adjustment of the operational mode"
Within the scope of the dissertation project new approaches in module design are to reach higher desalination performance. By means of experimental studies on different labscale testsamples a preselection of appropriate membrane and module geometries are to be performed. The main evaluation parameter is the overall specific energy demand for water production. Therefore new module designs have to feature effective heat recovery and low hydraulic pressure losses.
Theoretical and experimental studies on the transport phenomena will lead to the development of a physical model to simulate the behaviour of the new module design. A special focus will be the influence of feedwater salinity on the transmembrane water flux dependent on different operating conditions such as hydraulic flow condition, temperature and pressure.
A test facility for the characterization of membrane samples and module prototypes is currently under construction. The results will be used to validate the calculation model. Afterwards further thermodynamic optimization can be performed by means of simulaion.
Promising module variants will be fabricated and characterized in full scale. To prove upscale potential, a multi-module pilot plant will be installed and monitored. A comparative evaluation of the new MD-modules with conventional desalination technologies, in particular the currently used MD-technology, is aimed.
The project will be supervised by Prof. Dr.-Ing. S. Ripperger of the Chair of Particle Process Engineering at the University of Kaiserslautern. The work will be performed at the Fraunhofer ISE in Freiburg.
Desalination using membrane distillation: Flux enhancement by feed water deaeration on spiral-wound modules
Desalination using membrane distillation: Experimental studies on full scale spiral wound modules
Evaluation of MD process performance: Effect of backing structures and membrane properties under different operating conditions
Membrane Distillation A Thermodynamic, Technological and Economic Analysis