Port Of Rotterdam Research Articles

Undermining the ‘Polder Model’: Workers’ Militancy and Trade-Union Leadership in Four Dutch Wildcat Strikes, 1963–1970

All over Europe, workers’ insubordination in the 1960s and 1970s became manifest in a growing number of wildcat strikes. In the Netherlands, under the guise of the so-called consensual ‘polder model’, trade unions were part of a repressive system of industrial relations. From 1963, rank-and-file opposition in ‘unofficial’ strikes forced the ‘official’ unions to abandon their support of restrictive wage policies. After a huge wildcat strike in the port of Rotterdam in 1970, the union leadership changed its policy and began to initiate strikes. In this article, rank-and-file mobilization and the union leaderships’ reaction are analysed in four wildcat strikes between 1963 and 1970. It concludes that in these strikes the union leadership and rank-and-file members, while opposed to each other, were also mutually dependent. The union leadership was forced to adapt to pressure from below, and strikers had to rely on the bargaining ability of union officials to reach an agreement with the employers. Both parties had to accept an involuntary symbiosis. In this way, the attachment of the trade-union leadership to the top-down consensus in the ‘polder model’ was undermined.

CHALLENGES IN DESIGNING A WIND FARM ON AN ERODING BEACH ALONG THE DUTCH COAST

The Dutch energy company Eneco received the concession to construct a 116 MW windfarm on the Maasvlakte-2, a recent large seaward port extension of the Port of Rotterdam. The land reclamation is protected partly by a hard sea defence and partly by a soft sea defence, consisting of a sandy beach and adjacent dunes. Twelve wind turbines with a monopile foundation will be constructed on the beach, close to or in the waterline. The beach is erosive and is maintained by regular beach and foreshore nourishments. Designing and constructing wind turbines in this dynamic environment forms an unprecedented challenge.

Logistics of Smart Port in Ukraine: Problems and Prospects in the Conditions of Sustainable Development

Every day, the global logistics industry faces new challenges – both due to the Russian invasion of Ukraine and due to economic instability in global markets. The pandemic and the disruption of traditional supply chains are forcing companies to change their production geography. Accelerated digitization of people's and companies' livelihoods is contributing to the transformation of classical logistics, and in the end, those players who create an environment of additional services for delivery support, thereby forming resilience to risks, are winning. In this regard, there is a need to develop theoretical and applied aspects of the transition of port logistics to sustainable development through the introduction of smart port technologies that contribute to the achievement of a number of sustainable development goals, such as: 1: no poverty, 2: zero hunger, 3: good health and well-being, 8: decent work and economic growth, 9: industry innovation and infrastructure, 11: sustainable cities and communities, 12: responsible consumption and production, 13: climate action, 14: life below water, 17: partnerships for sustainable development. The theoretical basis of the research was scientific works of scholars from different countries and periods in the field of logistics, sustainable development, individual provisions of international framework documents, including the UN Conference on Environment and Development's Agenda for the 21st Century, the Declaration on Environmental Protection, and the Johannesburg Declaration on Sustainable Development. Official data from the ports of Gdansk, Rotterdam, and Hamburg, the International Association of Ports and Harbors (IAPH), the World Ports Climate Initiative (WPCI), the World Bank, and the Administration of Seaports of Ukraine (USPA) were used as initial information for analysis and concluding. As a result of summarizing the theoretical and methodological foundations of logistics, the article proposes the Conceptual Model of the Subject Area 'Smart Port', the quintessence of which lies in the symbiosis of the paradigms of scientific and technical development and sustainable development. This made it possible to expand the existing scientific basis of the transport logistics and transport systems sphere. The prerequisites for the emergence of the smart port are analyzed. The leading container ports of different generations are grouped. Special focus is on Ukraine, one of the largest grain exporters in the World. The prospects for the transition of Ukrainian ports to the fourth category (generation) of development are outlined. To successfully implement the strategy for the development of Ukrainian seaports for the period up to 2038, an optimization management model for logistics processes was developed based on the concept of a gaming approach.

Navigating cyber resilience in seaports: challenges of preparing for cyberattacks at the Port of Rotterdam

PurposeCyber resilience has emerged as an approach for seaports to deal with cyberattacks; it emphasizes ports’ ability to prepare for an attack and to keep operating and recover quickly. However, little research has been undertaken on the challenges of governing cyber risks in seaports. This study aims to address this gap.Design/methodology/approachGoverning cyber resilience is shaped by distributed responsibilities, uncertainties and ambiguities. The authors use this conceptualization to explore the governance of cyber risks in seaports, taking the Port of Rotterdam as a case study and analyzing semistructured interviews with stakeholders, participatory observation and policy documents and legislation.FindingsThe authors found that many strategies for governing cyber risks remain dedicated to protecting computer systems against cyberattacks. Nevertheless, port stakeholders have also developed strategies in anticipation of disruptions. However, these strategies appear informal and uncoordinated due to a lack of information exchange, insufficient knowledge regarding cyber risks and disagreement about how to make the Port of Rotterdam cyber resilient. What mainly hampers the cyber resilience of the port is the lack of a comprehensive regulatory framework and economic incentives. The authors conclude that resilience is merely an ideal at the Port of Rotterdam, meaning related governance strategies remain incremental and await institutionalization.Originality/valueThis paper offers insights into the cyber resilience of critical socio-technical systems, which have been underexposed in cyber resilience debates, but, when exploited, can manifest in large-scale disruptions.

Diversity of perspectives in biodiversity conservation: A case study of port land use in Antwerp and Rotterdam

Conflicts of interest often undermine conservation initiatives against biodiversity decline. Effective decision-making requires a deeper understanding of the positions, criteria, concerns, and perspectives of stakeholders. However, managing so many perspectives can be difficult, and if not done well, conflicts arise which make it difficult to achieve conservation goals. The purpose of this study is to demonstrate that identifying areas of consensus is a good starting point to generate more effective debates and address complex issues. To do this, we investigate the diversity of perspectives regarding biodiversity conservation schemes among stakeholders in the studied ports of Antwerp and Rotterdam. Using Q-methodology, a semi-quantitative technique that enables us to systematically study the subjective views of stakeholders involved in a topic, we identified and organized a range of shared perspectives into three groups, known as factors. A total of 20 participants sorted 45 statements according to their perceptions and objectives, from −4 ‘most disagreeable’ to 4 ‘most agreeable’. Then, respondents explained their rankings in a post-sorting interview. Next, the data was analyzed quantitatively and qualitatively. The quantitative analysis was conducted in two parts:(i) Dividing respondents into groups based on similar perspectives and (ii) coupling distinguishing statements with one of the factors characteristic of that viewpoint. Finally, in a qualitative analysis, we used the distinguishing statements and insights from interviews to create narratives and titles for the three factors: (1) Ports are key for our economic wealth, hence port development should continue, (2) Nature first, and (3) Multi-actor governance. Our findings confirm consensuses in three areas: policy, land use, and mitigation tactics. Interestingly, all narratives unanimously agreed on the importance of regulating port development and land use changes via legislation and environmental impact assessments. However, they debated the rigidity of legislation and whether offsetting port expansion (and associated land and resource use claims) should take place locally or internationally. We also found that decision-making mostly followed a human-centered perspective, where economic values were more relevant than intrinsic ones. These insights can serve as a baseline for stakeholders to form coalitions around areas of consensus to depolarize debates and avoid decision-making gridlocks.

The strategy of the port development company; a framework based on the business ecosystems perspective and an application to the case of Port of Rotterdam

This paper advances the conceptual understanding of strategies of port development companies (PDCs) through applying the business ecosystem perspective. This leads to a distinction between four stylized strategies for PDCs and associated types of services: minimalist (six services), integrator (six services) and ecosystem services (six services). An analysis of the services provided by a PDC reveals which strategy they follow. This approach is tested through a case study of Port of Rotterdam Authority (PoR for short) the state-owned PDC in charge of developing Rotterdam's port complex. This case study yields three important conclusions: first the relevance of the identified service types is confirmed, as PoR is or has been active in providing 15 of the 18 identified service types, more specifically all six ‘minimalist services’, all six ‘ecosystem services’ and three of the six ‘integrator services’. Second, PoR follows a ‘platform provider’ strategy. Third, the provision of ‘ecosystem services’ seems to become a more important part of PoRs activities. The number of provided ecosystem services has grown between 2006 and 2021 and investments in ecosystem services account for an increasing share of PoRs total investments. These results provide a basis for further research, amongst others to better understand factors that may influence the strategies of PDCs.

COVID-19 outbreaks among crew on commercial ships at the Port of Rotterdam, the Netherlands, 2020 to 2021.

BackgroundDuring the COVID-19 pandemic, international shipping activity was disrupted as movement of people and goods was restricted. The Port of Rotterdam, the largest port in Europe, remained operational throughout.AimWe describe the burden of COVID-19 among crew on sea-going vessels at the port and recommend improvements in future infectious disease event notification and response at commercial ports.MethodsSuspected COVID-19 cases on sea-going vessels were notified to port authorities and public health (PH) authorities pre-arrival via the Maritime Declaration of Health. We linked data from port and PH information systems between 1 January 2020 and 31 July 2021, derived a notification rate (NR) of COVID-19 events per arrival, and an attack rate (AR) per vessel (confirmed cases). We compared AR by vessel type (workship/tanker/cargo/passenger), during wildtype-, alpha- and delta-dominant calendar periods.ResultsEighty-four COVID-19 events were notified on ships, involving 622 cases. The NR among 45,030 new arrivals was 173 per 100,000 impacting 1% of vessels. Events per week peaked in April 2021 and again in July 2021, when the AR was also highest. Half of all cases were notified on workships, events occurring earlier and more frequently than on other vessels.ConclusionNotification of COVID-19 events on ships occurred infrequently, although case under-ascertainment was likely. Pre-agreed protocols for data-sharing between stakeholders locally and across Europe would facilitate more efficient pandemic response. Public health access to specimens for sequencing and environmental sampling would give greater insight into viral spread on ships.

Analysis of the Mooring Effects of Future Ultra-Large Container Vessels (ULCV) on Port Infrastructures

The size of container vessels is continuously growing, always exceeding expectations. Port authorities and terminals need to constantly adapt and face challenges related to maritime infrastructure, equipment, and operations, as these are the principal areas affected by the future Ultra Large Container Vessels (ULCVs). Maneuvring areas are at their limits, and mooring equipment is at an increased risk of being overloaded. This study aims to analyze the limitations that present mooring systems may face when ULCVs are subjected to wind and passing-ship forces exerted by a future ULCV and wind forces through Dynamic Mooring Analysis (DMA). A hypothetical and massive future ULCV with a capacity of 40,000 TEU is compared to the Emma Maersk, which is a present vessel that regularly calls at container terminals. The Emma Maersk, with its current mooring arrangement, experiences higher motion than future ULCVs, which experience higher forces but are also moored with more and stronger lines. This translates into considerably higher loads in the mooring system, potentially compromising safe mooring conditions at the terminal. Mitigating measures are proposed in the study to face these limitations. In addition, the study explores the potential of new and innovative mooring technologies, such as high-strength synthetic ropes and smart mooring systems, to address the challenges posed by ULCVs. A container terminal at the Port of Rotterdam, Europe’s largest sea port, has been analyzed as a case study. The terminal is located next to a busy fairway that leads to other container terminals, justifying the need to analyze both wind and passing-ship effects on moored ships.

Ship behavior during encounters in ports and waterways based on AIS data: From theoretical definitions to empirical findings

Currently, the research on ship behavior during encounters focuses on evasive behavior during specific situations with existing risks of collision. However, the preliminary selection of encounters to refine the presented ship behavior is biased. To obtain a full understanding of all ship behavior during different encounters in ports and waterways, the encounter is defined from the viewpoint of the spatial-temporal co-existence of ships in the same waterway segments during the same period. Based on this definition, this paper investigates ship behavior through the encounter process with other ships. The proposed approach starts from the moment when the distance in between is minimum as the critical moment to recognize ship behavior change (course alteration and speed change) based on the Sliding Window algorithm. Thus, the encounter process is identified by the key behavior feature point into phases, being before decision-making, before the critical moment, after the critical moment, and after being past and clear. The relative movement factors are calculated according to the behavior status of both ships to describe the conditions, timing, and objective of behavior change during the dynamic process of encounters. The empirical findings based on one-year Automatic Identification System data in the port of Rotterdam are presented. In the overtaking encounters, as the give-way ship, about 14% of the overtaking ships do not take any evasive actions. Among the ships with behavior changes, the preference for course alteration and speed change is equal. As the stand-on ship, about 87% of the overtaken ships take cooperative maneuvers to facilitate the encounter, in which deceleration seems the primary choice. The timing of overtaken ship's behavior change is later than overtaking ship. For overtaking ships, the objective of course alteration is a clear passing distance of about 5 times her beam, 100m for overtaken ships irrespective of her own size. Regarding speed, the overtaking ship aims to reach a relative speed of 0.3 times her own SOG, while the objective for the overtaken ship is fixed at around 2–3 m/s. In the encounters of ships sailing in the opposite direction, most of the ships take maneuvers to change their course or speed. However, within the influence distance of 2 km, over 76% of the ships do not take any evasive behavior, which implies a passing-by situation. Based on the recognized key feature points of behavior change, statistical tests show the objective of clear passing distance has been reached beforehand. The behavior change during head-on situations could be due to the precautionary behavior of officers onboard in case of interaction between ships. The findings enrich the knowledge of ship behavior during different types of encounters in real-life navigation, which can be further applied to simulation models for ship behavior in ports and waterways.

Cooperation between vessel service providers in ports: An impact analysis using simulation for the Port of Rotterdam

Cooperation between vessel service providers can improve the performance of ports. However, the potential impact of such cooperation has not yet been quantitatively addressed in the literature. We present an assessment using a port simulation model where the exchange of information has been made explicit. Cooperation is modelled as information exchange between the pilotage and towage service providers for the deployment of pilots and tugboats. A first application of the model is shown for the case of Port of Rotterdam. We find that time savings of up to 30% in waiting times can be achieved, while both service providers improve their performance. These findings provide empirical confirmation of the expected benefits of cooperation in ports as voiced in the literature. Furthermore, the results underscore the importance of moving beyond an ad-hoc synchronizations of these services towards systematic cooperation, to the benefit of ports as well as the service providers.

Evaluation of the renovation of an urban highway viaduct using citizen science low-cost noise monitoring

A main highway in Belgium (E17) has transected the city of Ghent with a viaduct since 1970. This highway is the main north-south artery for heavy traffic from and to the ports of Antwerp and Rotterdam. The viaduct has significant maintenance issues and was subjected to multiple noise control actions in the past. Since 2014 a local citizens initiative named 'Viadukaduk' -mimicking the sound of the viaduct to allow public engagement in resolving the environmental issues. In 2020, a major renovation was initiated. Prior to this renovation (in 2015) noise measurements were performed at two dwellings at either side of the viaduct. In 2020, at the beginning of renovation, measurements were repeated at the two dwellings. Post-renovation, the two datasets, 2015 and 2020/2022, have been used to perform a noise evaluation due to the renovation of the viaduct, including the impact of changes in noise barrier type, road surface and bridge joints. Preliminary results show a change of 7 dBA, although at the impact of the renovation itself is limited to 1 dBA. The data collected during the renovation illustrate the different phases: speed reduction and lane changes, removing old screens, placement of new screens, refurbishing bridge joints etc.)

A robust optimization approach for platooning of automated ground vehicles in port hinterland corridors

Modern ports face significant challenges as strategic nodes of global supply chains, being responsible for the coordination of inbound and outbound flows at deep-sea and in hinterland transport corridors. Digitization and the adoption of disruptive technologies can help ports to tide over operational challenges. Automated Ground Vehicles (AGVs) are an integral part of operations at many modern ports, especially inside container terminals. With the shift to automated transport outside of the terminal areas, these AGVs may form platoons to establish an efficient port hinterland transport corridor. In this work, we propose a new robust optimization approach to assess the time and cost-efficiency of applying such AGV platoons in a container pickup and delivery problem. We develop a bi-objective mixed-integer programming model, which simultaneously minimizes time and cost elements, and also considers emissions. Each transportation task can be carried out by AGVs or conventional trucks, while the number of available vehicles for each mode is uncertain (as they are used to connect different modalities of container transport). The robust optimization model is based on an ellipsoidal uncertainty set to handle this uncertainty and an augmented epsilon constraint method to obtain Pareto-optimal solutions for this multi-objective problem. The developed framework is evaluated in two case studies: the Port of Rotterdam in The Netherlands and the Port of Valparaíso in Chile, with different traveling distances in corridors to a dry port (200 km) and a pre-terminal (11 km), respectively. The results indicate that the new direct delivery scheme by AGV platoons is significantly more cost- and time-efficient than the benchmark and provides a low-carbon emission transportation mode. While the benefits of decreased dwell times (56% on average) and carbon emissions (on average by 10%) are similar for short and long traveling distances, the savings in cost increase (from 4.9% to 8%) with the increased distance in the Rotterdam case.

Port Competition through Hinterland Connectivity—A Case Study for Potential Hinterland Scope in North Rhine-Westphalia (NRW) Regarding an Environmental Policy Measure

Comparable port efficiency among ports of the European northern range leads to a competitive shift toward hinterland connectivity. North Rhine-Westphalia (NRW), having a high population and industry density and an extensive road, rail and waterway network, is prone to such inter port competition due to its proximity. Using a simulation model, the potential hinterland scope by each port and mode in NRW is depicted and a sensitivity analysis with increasing carbon tax rates is conducted. With an increasing tax rate, the scope for central areas of NRW, prone to a shift to rail transport, expands and become heavily contested among multiple ports. A major profiteer of an increase is projected to be the Port of Rotterdam due to its good connectivity at the cost of Antwerp. The market share of German ports is likely to stay the same with a mode shift occurring. Policy measures like a carbon tax not only have an effect on environmentally friendly mode shift but can severely impact the competitive situation of infrastructure components. While achieving the primary goal of transport sustainability, national interests might mandate the economical existence of a functioning maritime port, which leads to the consideration of additional measures when increasing carbon tax rates.

A practical guide to filing domain name complaints

This article first provides an overview of the background and functioning of different domain name dispute resolution procedures before providing tips and tricks for practitioners to make more efficient use of these procedures. These tips and tricks not only relate to the procedure itself but also to writing a clear and concise domain name complaint. This article is limited to alternative dispute resolution (ADR) procedures and will not discuss the case law of ordinary courts on domain names. The main focus of this article is the Uniform Domain Name Dispute Resolution Policy (UDRP), the world’s most important domain name dispute resolution policy. Given the background of the authors, who are based in the Netherlands, the UDRP is mainly compared to policies that play a role in Dutch, Benelux and European practice. Many cybercriminals cleverly use official-looking domain names that are slightly different from the official domain name (and trade mark), through which they can impersonate the trade mark owner. The scams associated with impersonations are numerous. Scammers frequently provide instructions for payment to a finance department while using email addresses purporting to relate to the manager (CEO fraud). In the Port of Rotterdam, there are many cases of so-called terminal spoofing: scammers pretend to be the owner of a tank terminal and send emails to foreign parties in which they offer oil in return for a deposit. The same domain name that is used for the email address is often linked to a website that purports to be the official website of a specific tank terminal, including pictures of the tank storage and the actual address. It often results in the actual tank terminal owner, unaware of what has happened, having to deal at the gate of the terminal with angry and deceived buyers.2

The market for biofuels: sustainable prospects for international shipping and the advances of the Port of Rotterdam

The market for biofuels: sustainable prospects for international shipping and the advances of the Port of Rotterdam

Формирование системы «умных» портов в логистической инфраструктуре Северного морского пути

Forming a system of smart ports in the logistics infrastructure of the Northern Sea Route (NSR) has been analyzed. There are considered the cases of the current development of port infrastructure in the NSR, the world experience of implementing a smart port in the existing logistics infrastructure is analyzed, the ways to introduce this system into the port infrastructure of the Northern Sea Route to optimize logistics flows in the Russian Arctic are studied. The main share of volume indicators of ships in Russian ports in 2020 is illustrated. It has been stated that one of the leading positions, according to the main share of ship indicators, is occupied by the seaport of Murmansk, which, despite its location and climatic conditions, is the largest ice-free shipping hub not only in the Russian Federation, but in the global maritime space. A systematic approach including the general scientific and special research methods is applied: comparison, formalization, generalization, classification, analysis, synthesis. Based on the comparative analysis of the parameters of the traditional and smart ports, the key components of the smart port are identified: smart infrastructure, smart traffic flows, smart logistics. The large and technologically developed port of Rotterdam is presented as an example of successful development of the port infrastructure. Large-scale digitalization and innovations in the work of the hydrometeorological service of the port contribute to improving the operational efficiency and safety of ships, as well as reducing polluting emissions. It is proposed to take as a basis the studied digital innovations in the port of Rotterdam for the transformation of the ports of the Russian Arctic.

Coalition formation and cost sharing for truck platooning

Truck platooning consists of one or several trucks driving very closely behind the platoon leader with the help of technology. Platooning reduces fuel consumption, carbon emissions and congestion while increasing road safety and the productivity of trucks and drivers. This article focuses on the advance planning of platoons. First, we study platoon formation from a system-wide optimization perspective. We formalize the underlying optimization problem and we propose exact and approximate solution approaches that appear to perform very well in instances of practical size. Second, we posit that truck platooning is much more likely to develop efficiently among multiple operators. This involves a shift in business relations between freight operators through cost sharing. We make use of cooperative game theory to study cost allocations among players. Our analysis shows that a compromise is needed among existence, stability and computational efficiency. However, we propose cost allocation rules for cooperative platooning games that perform very well in practice with regard to their stability. Finally, we propose an illustrative example based on the settings of the Port of Rotterdam and we provide a series of insights.

Ignorance-led port policing? The limits of information sharing–based policing in the North Sea Canal Area and Port of Amsterdam and in the Port of Moerdijk

Abstract Whereas the Dutch government considers the Port of Rotterdam and Amsterdam Airport as crucial drug transport hubs for organized crime groups, there is scarce governance focus on the increasing shift of these groups to small, medium-sized, and (still) relatively anonymous Dutch ports, like the North Sea Canal Area (NSCA) and the Port of Moerdijk (PoM). They can be considered criminal diversion ports where port policing parties relies strongly on information sharing to establish intelligence-led port policing. What has remained un(der)studied are not only these criminal diversion ports, but also, and more specifically how and why (frontline) port policing staff (do not) share information and intelligence (position) with one another other. What are their motivations to withhold or share information? That is the key research question answered in this contribution by comparing two recent studies, one on the NSCA (Eski, Y., Boelens, M., Mesic, A., and Boutellier, H. (2021). Van Verhalen naar Verbalen: Een verkennende studie naar de aanpak van ondermijnende drugscriminaliteit in het Noordzeekanaalgebied en de haven van Amsterdam (NZKG). The Hague: Sdu.) and the other on the PoM (Fiddelers, V. [2021]. Intel aan het roer. Een studie naar informatiedeling binnen de politie ten behoeve van de aanpak ondermijnende criminaliteit in de haven van Moerdijk. Amsterdam: VU University.). By exploring comparatively the reasons the studies’ participants have, or think others have, for (withholding) information, this article considers to which extent Dutch small, medium-sized criminal diversion ports accommodate ignorance-led port policing (Reiner in Shepherd, J., Pease, K., Reiner, R., Squires, P., and Westmarland, L. (2010). ‘Debating Policing Research: A Research Council for Crime and Justice? Jonathan Shepherd and Ken Pease Call for Medical Research Standards to be Replicated in Policing Studies. Robert Reiner, Peter Squires, and Louise Westmarland respond.’ Criminal Justice Matters 80(1): 2–5.).

Characterization and classification of estuarine suspended particles based on their inorganic/organic matter composition

An 11 hours survey was performed on the 17th of September 2014 in the Rhine Region Of Freshwater Influence (Rhine-ROFI) about 10 km downstream of the mouth of the Rotterdam Waterway during calm weather conditions. Suspended Particle Matter (SPM) measurements were performed during a full tidal cycle, near the seabed, at neap tide, and samples were taken at 0.6 meter above bed for on-board analysis. The measurements were performed with (a) LISST 100X, a submersible particle size analyzer, (b) LISST-HOLO, a submersible digital holographic camera, (c) a home-made underwater camera and (d) an on-board LabSFLOC2 video microscopy equipment that used in-situ collected samples. The first aim of the present study was to compare the results obtained from the different monitoring techniques and to characterize the different types of suspended particles found in-situ. It was found that that the highly anisotropic particles present in the water column lead to multiple peaks in the Particle Size Distributions (PSD) found using the LISST 100X. Using the LISST-HOLO, underwater camera and LabSFLOC2 camera these particles could properly be imaged and meaningful PSD’s were obtained using these techniques in the size range > 20 μm. LabSFLOC2, LISST-HOLO and the underwater camera moreover provide information on the size and aspect ratio of particles. On the other hand, LISST 100X can be used to detect the fine fraction (<20 μm), a size range that is not accessible for the other techniques. From the analysis of the data on the survey day, three classes of particles were identified, based on composition rather than size (the sizes given here are purely indicative): (1) mineral (inorganic) sediment particles in the range size 5 - 20 μm, (2) organic/inorganic aggregates in the size range 20 - 200 μm and (3) organic particles in the size range > 200 μm. A large range of settling velocities (0.1 - 10 mm/s) and aspect ratios between 1 and 10 were recorded by video microscopy (LabSFLOC2). This spreading in settling velocities and aspect ratio was due to the different properties (shape, effective density and size) of the particles in the water column. The second aim of the study was to reproduce the flocs found in-situ in the lab and investigate the kinetics of flocculation between inorganic and living organic matter. Laboratory experiments were conducted with grab samples obtained from Port of Rotterdam harbour and living microalgae (Skeletonema costatum). The results of these experiments showed a shift in effective density upon addition of living algae to the sediment, which confirmed the flocculation ability between sediment and microalgae. The flocculation occured on a timescale of minutes and lead to flocs having a large spread in density for a given size, due to the heteregeous inorganic/organic composition of the flocs. This spread in density was at the origin of the large range of settling velocities for a given floc size observed in-situ, which leads to conclude that organic matter should be an important input parameter in sediment transport models.

Physicochemical model for simulating the chemical processes during the crystallization of minerals from spent ion exchange regenerant

Traditionally, industrial processes produce wastes that, even though often containing useful materials, are discarded, contributing to environmental pollution and depletion of natural resources. An example of such wastes are brines, flows of concentrated salts, produced in water treatment processes, which are now routinely discharged into receiving water bodies. Brines however can also be considered as flows of reusable materials which should be recovered, and the Zero Brine cooperation project aims to develop processes for that purpose. For a demineralized water production plant in the port of Rotterdam (the Netherlands), a closed water processing cycle was proposed to treat the large volume of spent Ion Exchange (IEX) regenerant brine which, apart from recovering demineralized water, is also intended to produce magnesium (Mg2+) and calcium (Ca2+) salts, with the highest purity possible, from the otherwise discharged brine. The process scheme includes nanofiltration (NF) for separating mono- and multivalent ions, followed by sequential chemical precipitation of Mg2+ and Ca2+ ions from the NF concentrate, and production of demineralized water by evaporation of the NF permeate. The concentrate of monovalent ions produced in the evaporator, essentially a concentrated sodium chloride solution, in its turn might be reused for IEX regeneration. Part of the supernatant of the sequential precipitation may be fed to the evaporator as well, but bleeding the other part of this supernatant is essential in order to maintain process stability, avoid accumulation of minor pollutants, and reduce scaling. In this study, various scenarios to operate the process were modeled, using PHREEQC and Excel. According to the simulation results, recovery of ≈97% of Mg2+ and Ca2+ is possible, the latter with a higher purity than the former. The main factors affecting the results are the concentration of carbonate present in the spent IEX regenerant, as well as characteristics of the NF membrane and the dosing of sodium hydroxide in the sequential precipitation steps. The results of the simulations were used for the design and operation of a pilot plant, comprising all mentioned process steps.