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Lime is crucial for many sectors of the economy including construction, agriculture, power generation, and manufacture. Lime plants are responsible of about 1.4 % of the global anthropogenic emissions of CO2. The majority of these emissions (over 60 %, according to IEA 2020), generated by the calcination of CaCO3 (i.e. process emissions), can only be avoided through efficient CO2 capture. To capture the CO2 process emissions, post-combustion and oxy-fuel combustion technologies have the potential to be deployed industrially. Among them, Carbonate Looping (CaL) is one of the most promising processes because of its competitive CO2 avoidance costs and low energy requirements (i.e. specific primary energy consumption per CO2 avoided, SPECCA) (e.g. Astolfi et al. 2019). It uses CaO as sorbent to bind CO2 in a carbonator. The CO2 is released in an oxy-fired calciner, operating at around 900 °C, exiting in a high purity stream. For the particular case of the cement and lime industry, the CaL process can exploit the synergies of the calcination; thus, increasing the overall economic and thermodynamic efficiency. To avoid the manifold penalties associated with oxy-firing the calciner (e.g. capital and operation cost of an air separation unit, contamination of CO2 stream, and increase in SPECCA), the heat can be provided indirectly through an external combustor. A proven way to do this is via heat pipes, which transfer heat by means of evaporation and condensation of a working fluid, e.g. sodium. The viability of this Indirectly Heated Carbonate Looping (IHCaL) process was demonstrated with more than 1000 hours of operation in a 300 kWth pilot facility at the Technical University of Darmstadt, Germany. Some of the most important milestones were: capturing CO2 from real combustion flue gas, with more than 85 % capture rate in the carbonator; recirculation of combustor flue gases into the carbonator; and fuelling of the combustor with propane, coal, and solid recovered fuel (SRF) (Hofmann et al. 2022; Reitz et al. 2016). Nevertheless, still some key elements have to be demonstrated in order to deploy the IHCaL technology into the industrial scale (cf. Greco-Coppi et al. 2021). This work presents the design of a 2 MWth demonstration facility with the main objective of driving the IHCaL forward into the full-scale application for the decarbonization of lime and cement production. Lime Plant Hönnetal, in Germany, was selected as the host facility. For the design of the demonstration plant, reactor and process simulations were performed. The sorbent reaction and deactivation models were developed using data from thermogravimetric analysis (TGA). The reactor models were validated with the results from the pilot testing in the 300 kWth scale. These models were integrated in the Aspen PlusTM process models and used to optimize the design of the demonstration facility. The objectives of the demonstration plant are: (i) demonstrate the application of the IHCaL into an industrially relevant environment; (ii) optimize and validate the utilization of solid fuels (including SRF) in the combustor with capture rates higher than 90 %; (iii) deploy a solid/solid heat exchanger to recover heat between the solid circulating streams; and (iv) demonstrate the feasibility to operate the indirectly heated calciner in industrially-relevant conditions (CO2 recirculation and steam fluidization). Within this work, the methods for the scale-up will be discussed, the design of the plant will be presented, and the operating conditions will be reported. The construction of the demonstration plant may take place within a follow-up project to the ACT ANICA project, starting in the year 2024. In that case, the demonstration facility would be operative by 2026; thus, enabling a first IHCaL industrial application into a lime or cement plant by 2030.

No abstracts are to be cited without prior reference to the author. Modelling of fish movement behaviour within a heterogeneous marine environment is a challenging but also key issue for understanding the effect of environmental factors and climatic change on fish processes (growth, distribution, mortality, reproduction). Fish movement models have the capability to encompass the combined effect of environment and empirical knowledge of fish individuals as energy requirements, known preys and predators, swimming capacities into a unified framework (Planque et al., 2011). Following an Individual Based Model (IBM) approach, a fish movement model has been developed to simulate the active movement of adult anchovy in the Bay of Biscay (BoB) in response to the spatio-temporal variations of both biotic and abiotic factors, as well as its internal conditions based on a bioenergetics model

No abstracts are to be cited without prior reference to the author.Deep-sea fisheries in the West of the British Isles have experienced in only two decades many changes regarding the size of the fleets, engine power and fishing gears, fishing grounds and depth while signs of depletion of deep-water stocks and damages to the seabed have led to an increasing number of management rules aiming at ecosystem conservation and at protecting stocks from unsustainable fishing pressure. As deep-water scientific surveys are scarce, abundance indices have been lately estimated using a database containing the catch composition of 29 000 hauls and provided by two organizations from the French fishing industry through a science–industry partnership. Catch composition reflects the combination of the influence of the above factors and the “true” species distribution, itself depending on environmental factors varying in space and time. It is therefore impossible to treat haul-by-haul datasets by standard analyses as they generally require independent observations and normal distributions of continuous variables. Various multivariate analyses and clustering methods were applied in an attempt to characterize the spatio-temporal variability in species abundance and to identify structuring factors and species associations in the catches. Two temporal scales were considered: seasonal and interannual. The relevance of the different methods employed and the information they provide were discussed and results were analysed with stock assessment and management options for those mixed fisheries in perspective.

No abstracts are to be cited without prior reference to the author.A database of tallybooks, from skippers' own logbooks, provided by the French industry involved in deep-water fishing to the west of the British Isles was used to standardise blue ling Landings per Unit of Effort (LPUEs). The data covered the years 1992-2008 with more extensive data for the period 2000-2007. For each haul, landings by species, tow duration, depth and location were reported. Compared to EU logbooks, this database is on a haul by haul basis instead of being aggregated by fishing sub-trips combining hauls from the same day, ICES rectangle and gear. Moreover, it includes depth, which is a major factor for catch rates in deepwater fisheries. LPUEs were estimated from Generalised Additive Models (GAMs) with depth, vessel, statistical rectangle and zone by year as explanatory variables. Owing to the statistical distribution of landings rates, landings were modelled by a Tweedie distribution, which is a compound Poisson distribution and allows to handle data with many zeros, as it is typical for catch data. In order to investigate how to reliably track stock trends, LPUEs were estimated in five regions for different subsets including or not the spawning season, when blue ling aggregates, or considering tows where blue ling was only a bycatch. The results based on the tallybook data indicated that blue ling LPUEs have been mainly stable over the past decade. This is consistent with stable mean length in the landings. Haul by haul data are suitable to derive abundance indices for deep-water fisheries assessment.

Monitoring noise pollution in urban areas in a more systematic manner has been gaining traction as a theme among the research community, especially with the rise of smart cities and the IoT. However, although it affects our everyday life in a profound way, monitoring indoor noise levels inside workplaces and public buildings has so far grabbed less of our attention. In this work, we report on noise levels data produced by an IoT infrastructure installed inside 5 school buildings in Greece. Our results indicate that such data can help to produce a more accurate picture of the conditions that students and educators experience every day, and also provide useful insights in terms of health risks and aural comfort. Preprint submitted to the WSACC 2023 workshop, organized in the scope of the 9th IEEE International Smart Cities Conference 2023

International audience

Already today engine emissions from medium speed engines operating in protected areas or used for special applications are subject to ambitious emission reduction requirements. The driving force behind such requirements is not necessarily from regulatory bodies, but rather commercial, stemming from green operators or investors. Publicly exposed applications like passenger ships or the growing offshore wind turbine industry are two good examples. The emission targets are derived from the most stringent non-road mobile machinery emission rules. Unlike in IMO regulation, not only nitrogen oxides (NOX) but also carbon monoxide (CO), hydrocarbons (HC), particulate matter on mass (PM) and number (PN) base are limited due to their health and environmental impact. Building on our previously presented study to optimize a combined medium speed engine andaftertreatment system package for best fuel consumption and emission performance, we present our testing results of combining the ABC DZC engine family (1-4 MW) with a Hug Engineering DPF+SCR system yielding unprecedented ultra low emissions. On the engine testbed, a 2 MW ABC DZC series engine was combined with a modular Hug exhaust gas aftertreatment system consisting of a diesel particulate filter (DPF) with active regeneration and a selective catalytic reduction (SCR) system with the possibility to include also an oxidation catalyst. Inorder to achieve the challenging emission requirements as well as to optimize overall operating costs, the engine was de-tuned from its original IMO Tier II settings to a fuel efficiency optimized low PM emission setting. This was only possible at the expense of increased engine-out NOX emissions, which were reduced by the SCR system down to EU Stage V levels and further below. Variations of engine- and aftertreatment-setups were tested on full scale in generator and propeller operation mode cycles, yielding a robust concept to achieve well-below EU Stage V emission limits. Detailed investigations during our test campaigns concerning sub 23 nm particle emissions and black carbonrevealed even cleaner exhaust than seen today by DF LNG engines. The presented assembly is the first MW-sized medium speed engine to be certified according to EU Stage V and for the new Bureau Veritas notation “ultra low emission vessel” (ULEV). For further CO2 emission reductions beyond the ones achieved via the fuel consumption savings, the entire system was chosen to consist of biofuel- and synthetic-fuel-ready components, which is one of the next steps to reduce the overall impact for the environment. This novel concept of an ultra low emission medium speed diesel engine was chosen to be implemented as a propulsion and power system into a latest generation wind turbine installation vessel containing 25 MW total installed power which will be presented as well.

International audience

A resurgence of dam planning and construction is under way in several river basins where untapped hydropower potential could meet growing energy demands. In Africa, more than 300 new hydropower projects are under consideration. Yet, hydropower expansion is a contentious issue given the uncertainty in water and energy demand as well as the negative impacts of these infrastructures on other sectors. Despite calls for a more comprehensive evaluation of hydropower projects, most dams continue to be planned with traditional methods that neglect interdependencies between planning and management and the cumulative impacts of multiple new dams. Here, we use the transboundary Zambezi Watercourse in southern Africa to present a novel dam planning approach that integrates sequencing of planned reservoirs with adaptive, multipurpose operations to address increasing and competing demands for water, energy, and food in the region.Results show how seeking compromise through operations while constructing dams early improves environmental and irrigation objectives by 50% and 80%, with an 8% loss in hydropower compared to an operation and sequencing strategy that singularly maximizes hydropower. Alternatively, seeking compromise only through delayed dam construction yields modest environmental and irrigation improvements of 6% and 9%, respectively, with a 22% loss in hydropower. Our findings indicate that while additional hydropower capacity reduces structural energy deficits, operating policies emerge as the main driver of human-environmental tradeoffs. Consequently, traditional single-objective operating policy selection may lead to erroneous perceptions of tradeoffs across infrastructure options. The robustness of this result is tested under an ensemble of stochastic hydrologic projections where environmental flow and irrigation deficits are found more sensitive to operations than shifts in water availability. The predominance of operating policies is relevant for improving multi-objective dam planning in other river basins already fragmented by dams built in the 20th century.