dr.ir. PM (Ellen) Slegers

dr.ir. PM (Ellen) Slegers

Assistant Professor

In my research I focus on developing approaches for prospective sustainability assessment of biobased chains, which are commonly at low maturity or so-called technological readiness level (TRL).

Our population is growing and to establish a durable transition it is essential to identify the production chains that sustainably use available resources, ensure food provisioning, produce the marketable products society needs while simultaneously having the lowest environmental impact possible, positive social and economic impact. It is not realistic to evaluate all the possibilities and we should take advantage of the flexibility at earlier stages of development to pre-select the most promising options. Therefore, we should not assess the sustainability ‘after the fact’.

The main challenges that my research focusses on are to deal with limited and uncertain data available for immature biobased technologies and to quantify the expected environmental, economic and social impacts and trade-offs between them. My research aims at developing a robust approach to quantify sustainability trade-offs based on uncertain and limited data. My team develops simulation models using approaches from Process Systems Engineering (PSE), Operations Research (OR) and sustainability assessment to quantify the expected performance and related system-wide sustainability impacts of low technological-readiness biobased systems. Close collaboration with experts within the disciplines primary production (‘feedstocks’) and conversion (‘biorefinery and processing’) is required to ensure validity of the developed mathematical models and resulting early sustainability assessment.

In various projects we have used simulation models to explore the technical performance of micro-algae cultivation which is an important basis for the sustainability assessment. A similar systems approach was then used to assess the environmental and economic sustainability of biobased processing options as well as that of feedstock production and processing. Recently we have developed a models to design a biorefinery including feedstock selection, processing technology, products to derive from the feedstock. In addition, for biobased systems the logistic decisions can be challenging, for example which suppliers to select and where to position micro-algae cultivation farms. In the PhD project of Hanna Böpple a value chain for fish sludge valorisation is designed. In there the challenge is to conceptually design the logistic chain for a novel value chain and at the same time have a prospective assessment of expected economic and environmental impacts. Dealing with limited amounts of data is focussed on the Digital Twins project, where we develop a blueprint for a Digital Twin in context of waste valorisation in sub-saharan Africa. In that project we identify which model approaches can be exploited further to increase waste valorisation and thereby improve sustainability for the involved actors. In the PhD project of Emmanuel Anom on food waste valorisation the focus is on addressing the trade-offs in sustainability objectives, also between the various actors in the chain.

Recently finished student projects

MSc thesis (36 ects)

  • Logistic viability of cultivating microalgae on aquaculture wastewater in Norway
  • How to turn polyhydroxyalkanoates production into an economic and environmentally sustainable process chain?
  • Microalgae as an ingredient for seafood analogues
  • Life cycle assessment and techno-economic analysis of the SLAM-DUNK value chain
  • Putting microalgae as an ingredient for meat replacers into perspective: Evaluating four microalgal products using a blending model
  • Fatty acids from stearic acids: influence of temperature, stirring rate, and type of CNF; and the effect of upscaling on the environment
  • Developing a decision support tool for ex-ante LCA.
  • The costs of economically optimal mixed organic substrates for insect-larvae protein
  • Environmental sustainability assessment of microalgal biorefinery methods
  • The sustainable design of processing networks for agricultural residues using a modelling approach
  • A literature review of the sustainable supply chain optimization in dairy industry
  • Monitoring the regeneration of cellulose within a lignocellulosic biorefinery 
  • Sustainability analysis of current industrial versus Escherichia coli-based indigo synthesis and dyeing process
  • A Subglobal framework for benchmarking environmental performance. A case study for the Dutch Economy's Safe operating space
  • Bottom-up modelling of urban food-systems and their environmental impacts. Case study of the environmental impacts of Almere's food consumption. See: https://doi.org/10.1016/j.spc.2020.12.039
  • Utilizing heathland topsoil. Logistic implications for the Dutch province Gelderland
  • Development of a dynamic order-picking process in an operational environment. A case study for the internal distribution of cut flowers

BSc thesis (12 and 24 ects)

  • Investigating the economic and technical possibilities of mineral concentrates as fertiliser for arable farming in the Netherlands
  • The optimal source and supply chain for a Green Biomass Refinery in the Netherlands.
  • Benchmarking the sustainability of roses: comparative study between roses from Kenya and the Netherlands
  • Evaluating economic and environmental sustainability on a proposed circular tea lemonade supply chain using scenario analysis
  • Biobased sourcing, which options? Optimal distribution of biomass from feedstocks and by-products to different applications in a biobased economy
  • Evaluating the feasibility of a new waste valorization method in the tea lemonade supply chain; a case study in the Chinese tea industry 
  • Multi-criteria analysis of the adaptation of reverse logistics to an expanded deposit-refund system in the Netherlands

 

Teaching

  • BMO26806 Circular Economy
  • ORL20806 Decision science 1
  • ORL32806 Sustainability analysis (coordinator)
  • Summer School Bioeconomy (European League of Life Sciences)