Injection of water into wells is a common practice in offshore oil and gas installations, and here as in many other industries the water has to be deaerated before it is sent through miles of pipelines to reduce the risk of corrosion in those pipelines and other downstream equipment. It requires extremely low concentrations of dissolved oxygen for the corrosion of metals to begin, and removing the dissolved oxygen is currently done in large vacuum deaeration towers, a highly energy demanding process, along with additional injection of chemical oxygen scavengers. In many instances these processes are controlled in a feed-forward manner, where the operators rely on infrequent sampling and corresponding measurements to control the process. The possibilities for optimization in this field are thus numerous. The main challenges are online measurements of dissolved oxygen and their use in feedback control. This article gives a brief review of the state-of-the-art and investigates the potential of using dissolved oxygen as a reliable feedback parameter, taking inspiration from onshore waste water industries which have been dealing with dissolved oxygen feedback control since the 1970's.
This article is a feasibility study on using fluorescence-based oil-in-water (OiW) monitors for on-line dynamic efficiency measurement of a deoiling hydrocyclone. Dynamic measurements are crucial in the design and validation of dynamic models of the hydrocyclones, and to our knowledge, no dynamic OiW analysis of hydrocyclones has been carried out. Previous studies have extensively studied the steady state efficiency perspective of hydrocyclones, and have related them to different key parameters, such as the pressure drop ratio (PDR), inlet flow rate, and the flow spill. Through our study, we were able to measure the dynamics of the hydrocyclone's efficiency (ϵ) response to step changes in the inlet flow rate with high accuracy. This is a breakthrough in the modelling, control, and monitoring of hydrocyclones.
The goal of this paper is to introduce and design a cost-effective Oil-in-Water (OiW) measuring instrument, which will be investigated for its value in increasing the efficiency of a deoiling hydrocyclone. The technique investigated is based on Electrical Resistivity Tomography (ERT), whose basic principle is to measure the resistivity of substances from multiple electrodes and from these measurements create a 2-D image of the oil and gas component in the water. This technique requires the measured components to have different electrical resistances, such as seawater which has a lower electrical resistance than hydrocarbon oil and gas. This work involves construction of a pilot plant, for testing the feasibility of ERT for OiW measurements, and further exploring if this measured signal can be applied as a reliable feedback signal in optimization of the hydrocyclone's efficiency. Different algorithms for creating 2-D images and the feasibility of estimating OiW concentrations are studied and evaluated. From both steady state and continuous laminate flow perspectives, with respect to the objective which is to use this measurement for feedback control purposes.
Offshore de-oiling installations are facing an increasing challenge with regards to removing oil residuals from produced water prior to discharge into the ocean. The de-oiling of produced water is initially achieved in the primary separation processes using gravity-based multi-phase separators, which can effectively handle large amounts of oil-well fluids but may struggle with the efficient separation of small dispersed oil particles. Thereby hydrocyclone systems are commonly employed in the downstream Produced Water Treatment (PWT) process for further reducing the oil concentration in the produced water before it can be discharged into the ocean. The popularity of hydrocyclone technology in the offshore oil and gas industry is mainly due to its rugged design and low maintenance requirements. However, to operate and control this type of system in an efficient way is far less simple, and alternatively this task imposes a number of key control challenges. Specifically, there is much research to be performed in the direction of dynamic modeling and control of de-oiling hydrocyclone systems. The current solutions rely heavily on empirical trial-and-error approaches. This paper gives a brief review of current hydrocyclone control solutions and the remaining challenges and includes some of our recent work in this topic and ends with a motivation for future work.
INTRODUCTION. Seafaring is associated with higher occupational hazards and health risks than shore-based work. Telemedical maritime assistance services (TMAS) provide remote specialist medical support to seafarers. In Denmark, a unified national TMAS, Radio Medical Denmark (RMD), was established in 1995. This study aimed to describe the 30-year development and clinical activity of the RMD.
METHODS. This was a single-centre retrospective cohort study of all consultations provided by the RMD from 1 September 1995 to 31 December 2024. Data were extracted from annual reports based on original medical files, with organisational information from contracts and guidelines. No identifiable patient data were collected.
RESULTS. The RMD assisted 49,999 seafarers over 30 years, with annual consultations increasing from 240 in 1995 to 4,829 in 2024. The proportion requiring disembarkation or evacuation declined from >10% at the outset to approximately 5% today. The most common diagnoses were musculoskeletal (18.8%), dermatological (14.6%) and abdominal (11.5%). Since 2014, the proportion of Danish seafarers decreased from 38% to 15.1%, while Indian and Filipino seafarers increased substantially. Merchant vessels accounted for 55.7% of contacts, predominantly in the North Sea.
CONCLUSIONS. RMD has evolved into one of Europe’s largest public TMAS providers. Centralisation within an academic emergency department, combined with structured training and research, has supported sustained growth, improved decision-making and reduced evacuation rates.
FUNDING. None.
TRIAL REGISTRATION. Not relevant.
The ‘port managing body (PMB)’ plays a central role in the development of the port. Public funding for investment projects of the port managing bodies is common in the EU as well as most other countries. This paper adds to the body of knowledge on port investments and financing challenges with an analysis of data from two surveys that were carried in 2018 and 2023. This analysis yields the following conclusions. First, the PMBs in the EU have shifted their investments, in response to changing investment drivers. The increasing relevance of the transition to a net-zero economy leads to a shift towards investments in projects that reduce environmental effects and/or allow private investments in new green activities such as the production of zero-emission fuels. Second, financial bottlenecks are the most important bottlenecks for the execution of the projects of PMBs. Third, the PMBs have high aspirations with regard to public funding, both on the EU and national level. Fourth, there is a difference between two types of PMBs: state-owned commercial port development companies and the public sector embedded port authorities; the latter execute less projects without public funding and are more oriented on national public funding than on EU funding. Finally, the societal value creation of the investments of PMBs is used to justify public funding aspirations. The PMBs indicate that the majority of their investments create societal value, often by enabling emission reductions and by reduced local negative externalities.
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.
This article contributes to the accelerating development of methods for sustainability assessment (SA) to support maritime spatial planning (MSP), by proposing an ecosystem services based framework for SA. MSP is generally seen as an important approach to promote a more sustainable use of sea space. However, so far all sustainability concerns are not equally well represented in planning practice; in particular, social sustainability aspects such as social justice and sociocultural values related to human-nature connectedness receive less attention. We first explored concepts and principles related to sustainability assessment and social sustainability in the scientific literature. Based on this, we analyzed how far the present approaches to assessments in Baltic Sea EU Member States have been extended from environmental concerns to towards broader sustainability concerns so far. Using current best practice in two pioneering countries (UK and Sweden), we illustrated how social sustainability principles could match with applied social impact criteria, and further, how such criteria can inform an ecosystem services-based impact assessment framework. Based on existing frameworks, including the DPSIR (driving forces, pressures, state, impact, response) environmental assessment framework and the ecosystem service cascade, we propose a sustainability impact assessment framework for MSP (MSP-SA) integrating across sustainability dimensions and including assessment of distributional aspects of marine ecosystem service benefits. Finally, we discuss the applicability and further development of the framework in relation to present day sustainability assessment practice in MSP.
The main objective of this research is to present an improved and more accurate formula to estimate the reflection coefficient (K R ) for rubble mound breakwaters. Physical model tests were performed for this purpose and existing data was also considered. The evaluation of existing prediction formulas for K R based on the Iribarren number (ξ) shows that the scatter in the experimental results increases with increasing ξ. This is caused by the wavelength having greater influence on the reflection than the wave height and thus the use of the wave steepness is inappropriate. The influence of potentially dimensionless parameters on the wave reflection from literature was analyzed. The major dimensionless parameters were found to be the relative water depth (h/L) and the structure front slope angle (α). Hence, a formula to estimate wave reflection for rubble mound breakwaters based on these two parameters is proposed.
Hydrogen-electricity integrated multi-energy systems are promising approaches to reduce carbon emissions in ports. However, the stochastic nature of renewable energy and the imbalance between the renewable generation and load demand in ports necessitate the design of an appropriate coupled hydrogen-electricity energy storage systems (CHEESS). This paper proposes a multi-objective optimization model for CHEESS configuration in random unbalanced port integrated multi-energy systems (PIMES), aiming to minimize its life-cycle cost and carbon emissions through co-optimization of sizing and energy management. A hierarchical two-stage framework is proposed to solve the multi-objective model. The proposed optimization framework is applied to a real PIMES at the Ningbo-Zhoushan Port. The results show that the proposed method can save 10.54% of the monetary cost and 19.67% of carbon emissions over the entire life-cycle of the system. The study demonstrates that the proposed framework has the potential to generate significant economic and environmental benefits and provides a feasible solution for port authorities seeking to implement CHEESS, aiming to promote sustainability in port operations.