TY  - CHAP
A1  - Müller, Tim M.
A1  - Altherr, Lena
A1  - Ahola, Marja
A1  - Schabel, Samuel
A1  - Pelz, Peter F.
T1  - Optimizing pressure screen systems in paper recycling: optimal system layout, component selection and operation
N2  - Around 60% of the paper worldwide is made from recovered paper. Especially adhesive contaminants, so called stickies, reduce paper quality. To remove stickies but at the same time keep as many valuable fibers as possible, multi-stage screening systems with several interconnected pressure screens are used. When planning such systems, suitable screens have to be selected and their interconnection as well as operational parameters have to be defined considering multiple conflicting objectives. In this contribution, we present a Mixed-Integer Nonlinear Program to optimize system layout, component selection and operation to find a suitable trade-off between output quality and yield.
KW  - Mixed-integer nonlinear problem
KW  - MINLP
KW  - Process engineering
KW  - Paper recycling
KW  - Multi-criteria optimization
Y1  - 2018
SN  - 978-3-030-18499-5
U6  - http://dx.doi.org/10.1007/978-3-030-18500-8_44
SP  - 355
EP  - 361
PB  - Springer
CY  - Cham
ER  - 
TY  - JOUR
A1  - Altherr, Lena
A1  - Leise, Philipp
A1  - Pfetsch, Marc E.
A1  - Schmitt, Andreas
T1  - Algorithmic design and resilience assessment of energy efficient high-rise water supply systems
JF  - Applied Mechanics and Materials
N2  - High-rise water supply systems provide water flow and suitable pressure in all levels of tall buildings. To design such state-of-the-art systems, the consideration of energy efficiency and the anticipation of component failures are mandatory. In this paper, we use Mixed-Integer Nonlinear Programming to compute an optimal placement of pipes and pumps, as well as an optimal control strategy.Moreover, we consider the resilience of the system to pump failures. A resilient system is able to fulfill a predefined minimum functionality even though components fail or are restricted in their normal usage. We present models to measure and optimize the resilience. To demonstrate our approach, we design and analyze an optimal resilient decentralized water supply system inspired by a real-life hotel building.
KW  - MINLP
KW  - Buffering Capacity
KW  - Uncertainty
KW  - Water Supply Networks
KW  - Booster Stations
Y1  - 2018
U6  - http://dx.doi.org/10.4028/www.scientific.net/AMM.885.211
SN  - 1662-7482
VL  - 885
SP  - 211
EP  - 223
PB  - Trans Tech Publications
CY  - Bäch
ER  -