Concrete is the most widely used artificial material, and shapes the largest area of the built environment in the Netherlands. Its waste stream is responsible for the highest percentage of construction and demolition waste and fundamental knowledge for affordable high-grade applications from old concrete has already been introduced. More precisely, the development of technologies that can separate End-of-life (EoL) concrete into its constituents, facilitates its recycling and reuse into new building materials and not in low-quality applications. However, in terms of concrete recycling, there is insufficient communication of the novel technologies in the construction sector and supply chain systems are not introduced in real-world problems. The current research focuses on a closed-loop approach concerning the production of conventional concrete based on a supply chain design. Specifically, the conventional and closed-loop supply chain of the production of concrete are designed in accordance with the SCOR Model. The main differences are identified and a ‘Concrete-to-concrete Recycling Plant’ is proposed as a solution to the EoL problem. It argues to change completely the conventional supply chain of concrete, and therefore recommendations for its future location in an urban environment are given. Additionally, a calculation tool regarding the recycling plant is developed in order to evaluate the suggested solution. The present study demonstrates that for each category of concrete, either prefabricated or site-cast, a recycling plant should be located next to the prefabricated or mortar industry in order to diminish transportation and inventory costs, as well as take advantage of the operating speeds of the novel technologies that compose the plant. Results indicate that a recycling plant is in accordance with the current market conditions and constitutes an efficient solution to the EoL concrete treatment by making concrete a circular material. Further research is required on a laboratory scale in order to collect quantitative data, communicate the results, and consequently, increase the awareness and acceptance of recycled aggregates in the construction sector.

Controversial policies have always been subjected to severe social scrutiny and opposition. With the rise of megacities and complex transportation networks, there has been significant growth in the number of controversial policies in the field of transportation. There has been substantial research in the past regarding transport policies, their implementation and their acceptance. But most of these research focuses on particular factors that influence the acceptance of transport policies, and some of them focus on the acceptance levels before and after implementation of a policy. But, there is insignificant research that explains the acceptance of a controversial transport policy as a whole combining various factors from different domains and also focusing on the increase in acceptance after the implementation. This thesis aimed to fill the above-mentioned gap in research by systematically developing a theoretical list of factors influencing the acceptance of a controversial policy with the help of a thorough literature study, and furthermore observing the level of influence of these factors by performing a small-scale case study.

Biofuels are inextricably bound up with policy. Various drivers can be identified for the production and consumption of biofuels, such as environmental considerations, energy security and economic development. Therefore, biofuels may be an appealing option to policy makers. Biofuels are in general more expensive to produce than their fossil counterparts. Therefore, (support) policy is necessary to increase the competitiveness of biofuels. Policy makers can implement various measures to realize the potential benefits of biofuels, such as import- and export tariffs, imposing trade embargoes, offering subsidies, mandating blending targets and creating tax exemptions. However, the biofuel market is an international affair, because demand and supply of feedstock and biofuel are unequally distributed around the globe. In the past it appeared that domestic biofuel policies could have major unforeseen and unintended effects on the international bioenergy markets.

The influence of policy measures on the global bioenergy markets is not extensively investigated. Lamers et al. [2011] found that trade volumes were largely influenced by import duties, whereas trade routes were mainly driven by tariff preferences. In other words, it is found that there is some interaction between policies and patterns of international trade flows (in terms of volumes and routes) of biofuels and feedstock. However, the study performed by Lamers et al. [2011] did not explain the underlying mechanism. The aim of this research is to fill this knowledge gap. With this knowledge, decision making by policy makers may become better informed and aforementioned effects of policies may be reduced or even prevented.

The main research question addressed in this research is: Which mechanism can explain the effect of policies on emerging patterns in the international trade flows of liquid biofuels and feedstock? To answer this question, an agent-based model (ABM) of the international liquid biofuel markets is developed. If literature on international trade flows for bioenergy is reviewed, it appears that the models applied are usually general- or partial equilibrium models. Contrary to equilibrium models, ABM allows for heterogeneous actors with bounded rationality, the ability to learn and intrinsic behavioural traits. Above that, geographical aspects can be incorporated. It is hypothesized that these factors play an important role in international bioenergy trade. Therefore, this approach could be of added value to the current strand of literature in which equilibrium models are applied.

To limit the scope of this research, a case study is performed. In this case study a number of key players in the international biodiesel market are considered: the European Union, Indonesia and Malaysia. Since the take-off of the biodiesel industry (around the year 2000), the European Union has been one of the largest producers and consumers of biodiesel in the world. In addition, the European biodiesel market has been targeted as an export market for biodiesel and feedstock (palm oil) by Indonesia and Malaysia. In view of the case study, the focus of this research is on first-generation liquid biofuels.