Display omitted
•New paradigmatic technology concept to produce valuable compounds from wastes.•Smart combination of electrolysis and electrodialysis with anionic membranes.•MMO suits better than BBD ...to electrorefinery concept.•100 and 30 mA cm−2 are suitable for the electrolyzer and electroseparator units, respectively.•Maximum efficiency in the production evaluated was 8.77 mmol carboxylate kWh−1.
This study introduces an innovative approach to wastewater treatment that combines two electrochemical technologies: electrolysis and electrochemical separation facilitated by anionic exchange membranes. This integrated technology converts pollutants into carboxylates, which are valuable intermediates for further electrosynthesis and fuel production. The efficacy of this approach was demonstrated using synthetic wastewater containing phenol as a model pollutant, chosen for its well-documented characteristics that enable comparative analysis with previous studies. The treatment process utilized mixed metal oxides (MMO) anodes with a composition of Ti/(RuO2)0.8(Sb2O4)0.2 and a boron-doped diamond (BDD) anode. The investigation was structured to evaluate each component of the treatment system individually before examining their collective performance. Through a series of case studies, the research not only confirmed the feasibility of this innovative technology but also highlighted the need for further study on the optimization of operational parameters and electrode materials. Comparative analysis revealed that MMO anodes outperformed BDD anodes, achieving maximum carboxylate transport rates of 138.7 mmol m−2h−1. The efficiency of carboxylate separation from the solution where they were generated reached up to 54.6 mmol kWh−1, while the maximum overall production efficiency was 8.77 mmol kWh−1. The study further determined that current density significantly affects both the production rate and the extent of mineralization, identifying optimal densities of 100 mA cm−2 and 30 mA cm−2 for the electrolyzer and electroseparator units, respectively. This work provides valuable insights for the optimization of this promising wastewater treatment technology, with potential applications in various industries.
We present an analysis of the added value (AV) of downscaling via regional climate model (RCM) nesting with respect to the driving global climate models (GCMs). We analyze ensembles of driving GCM ...and nested RCM (two resolutions, 0.44° and 0.11°) simulations for the late 20th and late 21st centuries from the CMIP5, EURO‐CORDEX, and MED‐CORDEX experiments, with a focus on the Alpine region. Different metrics of AV are investigated, measuring aspects of precipitation where substantial AV can be expected in mountainous terrains: spatial pattern of mean precipitation, daily precipitation intensity distribution, and daily precipitation extremes tails. Comparison with a high‐quality, fine‐scale (5 km) gridded observational data set shows substantial AV of RCM downscaling for all metrics selected, and results are mostly improved compared to the driving GCMs also when the RCM fields are upscaled at the scale of the GCM resolution. We also find consistent improvements in the high‐resolution (0.11°) versus medium‐resolution (0.44°) RCM simulations. Finally, we find that the RCM downscaling substantially modulates the GCM‐produced precipitation change signal in future climate projections, particularly in terms of fine‐scale spatial pattern associated with the complex topography of the region. Our results thus point to the important role that high‐resolution nested RCMs can play in the study of climate change over areas characterized by complex topographical features.
Key Points
RCMs produce substantial added value over complex topography regions
High resolution improves precipitation spatial patterns simulation and extremes
RCMs are important tools for climate studies over complex topographical regions
Introducing digital twins to agriculture Pylianidis, Christos; Osinga, Sjoukje; Athanasiadis, Ioannis N.
Computers and electronics in agriculture,
20/May , Letnik:
184
Journal Article
Recenzirano
Odprti dostop
•Digital twins have not been established in agriculture yet.•Agricultural digital twins could be used pervasively on different spatial and temporal scales, and with varying levels of complexity.•An ...application-based roadmap for the adoption of digital twins in agriculture is proposed.•Agricultural digital twins are challenged to capture the interactions between living systems and their environment.
Digital twins are being adopted by increasingly more industries, transforming them and bringing new opportunities. Digital twins provide previously unheard levels of control over physical entities and help to manage complex systems by integrating an array of technologies. Recently, agriculture has seen several technological advancements, but it is still unclear if this community is making an effort to adopt digital twins in its operations. In this work, we employ a mixed-method approach to investigate the added-value of digital twins for agriculture. We examine the extent of digital twin adoption in agriculture, shed light on the concept and the benefits it brings, and provide an application-based roadmap for a more extended adoption. We report a literature review of digital twins in agriculture, covering years 2017-2020. We identify 28 use cases, and compare them with use cases in other disciplines. We compare reported benefits, service categories, and technology readiness levels to assess the level of digital twin adoption in agriculture. We distill the digital twin characteristics that can provide added-value to agriculture from the examined digital twin applications in agriculture and in other disciplines. Then, inspired by digital twin applications in other disciplines, we propose a roadmap for digital twins in agriculture, consisting of examples of growing complexity. We conclude this paper by identifying the distinctive characteristics of agricultural digital twins.
In the framework of the EURO-CORDEX initiative an ensemble of European-wide high-resolution regional climate simulations on a
0
.
11
∘
(
∼
12.5
km
)
grid has been generated. This study investigates ...whether the fine-gridded regional climate models are found to add value to the simulated mean and extreme daily and sub-daily precipitation compared to their coarser-gridded
0
.
44
∘
(
∼
50
km
)
counterparts. Therefore, pairs of fine- and coarse-gridded simulations of eight reanalysis-driven models are compared to fine-gridded observations in the Alps, Germany, Sweden, Norway, France, the Carpathians, and Spain. A clear result is that the
0
.
11
∘
simulations are found to better reproduce mean and extreme precipitation for almost all regions and seasons, even on the scale of the coarser-gridded simulations (50 km). This is primarily caused by the improved representation of orography in the
0
.
11
∘
simulations and therefore largest improvements can be found in regions with substantial orographic features. Improvements in reproducing precipitation in the summer season appear also due to the fact that in the fine-gridded simulations the larger scales of convection are captured by the resolved-scale dynamics . The
0
.
11
∘
simulations reduce biases in large areas of the investigated regions, have an improved representation of spatial precipitation patterns, and precipitation distributions are improved for daily and in particular for 3 hourly precipitation sums in Switzerland. When the evaluation is conducted on the fine (12.5 km) grid, the added value of the
0
.
11
∘
models becomes even more obvious.
This paper discusses the question about how to write a literature review paper (LRP). It stresses the primary importance of adding value, rather than only providing an overview, and it then discusses ...some of the reasons for (or not) actually writing an LRP, including issues relating to the nature and scope of the paper. It also presents different types of LRPs, advises on reporting the methodology used for the selection of papers for review, and the structure of an LRP. An important conclusion is that the heterogeneity in LRPs is very large. This paper also presents some of the aspects that the authors feel are important structural and contextual considerations that help produce high-quality review papers.
We review the challenges and future perspectives of regional climate model (RCM), or dynamical downscaling, activities. Among the main technical issues in need of better understanding are those of ...selection and sensitivity to the model domain and resolution, techniques for providing lateral boundary conditions, and RCM internal variability. The added value (AV) obtained with the use of RCMs remains a central issue, which needs more rigorous and comprehensive analysis strategies. Within the context of regional climate projections, large ensembles of simulations are needed to better understand the models and characterize uncertainties. This has provided an impetus for the development of the Coordinated Regional Downscaling Experiment (CORDEX), the first international program offering a common protocol for downscaling experiments, and we discuss how CORDEX can address the key scientific challenges in downscaling research. Among the main future developments in RCM research, we highlight the development of coupled regional Earth system models and the transition to very high-resolution, cloud-resolving models.
•Wastewater treatment plants retrofit with resource recovery and N2O control.•Retrofitting comes with improved environmental impacts and increased costs.•N2O control provides the best reduction of ...climate change impacts at lowest costs.•Combining technologies for resource recovery reduce lifecycle impacts.•Chemicals and electricity for resource recovery increase freshwater eutrophication.
To reduce greenhouse gas emissions and promote resource recovery, many wastewater treatment operators are retrofitting existing plants to implement new technologies for energy, nutrient and carbon recovery.
In literature, there is a lack of studies that can unfold the potential environmental and economic impacts of the transition that wastewater utilities are undertaking to transform their treatment plants to water resource recovery facilities (WRRFs). When existing, literature studies are mostly based on simulations rather than real plant data and pilot-scale results. This study combines life cycle assessment and economic evaluations to quantify the environmental and economic impacts of retrofitting an existing wastewater treatment plant (WWTP), which already implements energy recovery, into a full-scale WRRF with a series of novel technologies, the majority of which are already implemented full-scale or tested through pilot-scales. We evaluate five technology alternatives against the current performance of the WWTP: real-time N2O control, biological biogas upgrading coupled with power-to-hydrogen, phosphorus recovery, pre-filtration carbon harvest and enhanced nitrogen removal. Our results show that real-time N2O control, biological biogas upgrading and pre-filtration lead to a decrease in climate change and fossil resource depletion impacts. The implementation of the real-time measurement and control of N2O achieved the highest reduction in direct CO2-eq emissions (-35%), with no significant impacts in other environmental categories. Biological biogas upgrading contributed to counterbalancing direct and indirect climate change impacts by substituting natural gas consumption and production. Pre-filtration increased climate change reduction by 13%, while it increased impacts in other categories. Enhanced sidestream nitrogen removal increased climate change impacts by 12%, but decreased marine eutrophication impacts by 14%. The reserve base resource depletion impacts, however, were the highest in the plant configurations implementing biological biogas upgrading coupled with power-to-hydrogen. Environmental improvements generated economic costs for all alternatives except for real-time N2O control. The results expose possible environmental and economic trade-offs and hotspots of the journey that large wastewater treatment plants will undertake in transitioning into resource recovery facilities in the coming years.
Display omitted
Display omitted
•Amberlite HPR1100 can remove phenolic compounds from real olive mill wastewater.•Different adsorption behaviours for real and synthetic olive mill wastewater.•Acetone was the solvent ...that led to higher recovery efficiencies.•Adsorption is a feasible technology for phenolics recovery.
Olive mill wastewater (OMW) is rich in valuable compounds such as phenolic compounds. Amberlite@HPR1100 was applied as adsorbent to recover these added-value compounds from OMW. For synthetic OMW, Langmuir isotherm and pseudo-second order kinetic model were able to predict the experimental data instead for real effluent, were the Freundlich isotherm and the pseudo-first order kinetic model the best fits. The continuous process was also studied, for real OMW the tbp, tst and tex were 1.27 min, 84.4 min and 575 min, respectively. After 645 min of adsorption, 42 % of phenolic content was adsorbed into the resin. An industrial column for recovering phenolic compounds from OMW was designed, which should have around 5 m and 0.6 m of height and diameter, respectively, filled with 112 kg of resin (dry basis). The desorption process for real OMW with acetone 80 % recovery was accomplished after 5 h of contact.
Display omitted
•Only water is used as desorption eluent for the recovery of vanillin.•Vanillin recovered at 1.5 g/cycle, on average.•Elution with water fractionates vanillin/acetovanillone from ...vanillic acid.•Twenty-two cycles of feed/desorption performed.•Adsorption contributes to a greener process and low-cost vanillin.
In the concept of biorefineries, the production of added-value compounds from kraft lignin depolymerization is still hindered by the number of separation processes needed to purify the phenolic compounds. In this work, a sequence of oxidation, membrane filtration and chromatographic separation is proposed for the recovery of vanillin. The alkaline wet oxidation achieved a vanillin yield of 4.3% on lignin weight basis. The two-step membrane filtration reduced the initial organic load to 29.5 (±1.8) g/L in the final permeate. The chromatographic step enriches solutions containing vanillin by alternating the feed phase with desorption utilizing only deionized water. In 22 cycles, 71% of the vanillin fed is recovered with at an average 1.5 g/cycle. Recovered fraction has a vanillin concentration of 4.7 g/L which can be further concentrated. This presents a major breakthrough for vanillin production from oxidized softwood lignin as it simplifies the purification procedure, reducing costs with desorption solvents and avoiding acid use.
PDF
