Recovery Solutions Research Articles

Performance of a novel CO2 absorption and reverse electrodialysis system with different amine solutions for simultaneous energy and bicarbonate recovery

In this study, the performance of a novel integrated carbon dioxide (CO2) capture and reverse electrodialysis (RED) system was evaluated. The optimal operating conditions and carbon dioxide absorption and desorption mechanisms were identified. The proposed system utilizes a RED device to recover energy from the desorption step of the CO2 capture process, which is known to have high energy requirements in conventional processes. It has the potential as a hybrid process capable of recovering absorbent, energy, and bicarbonate through RED. To verify the performance of the system, CO2 loading, power density, and absorbent regeneration were evaluated using primary (monoethanolamine, MEA), secondary (diethanolamine, DEA), and tertiary (N-methyldiethanolamine, MDEA) amines. In the case of primary and secondary amines, carbamates, intermediate products, are formed and pass through the ion exchange membrane of RED, thereby achieving high power density. However, they are re-substituted with amines after passing through the ion exchange membrane (IEM), leading to the loss of absorbent. Conversely, in the case of tertiary amines, no intermediate products were formed, and excellent absorbent regeneration performance of more than 99.9% was demonstrated through multi-stage RED. Through this, the feasibility of future applications of this technology was confirmed.

All-In-One solution for simultaneous phosphonate degradation and orthophosphate recovery by NiFe-Layer double Hydroxide/PDS

Phosphate recovery presents an effective solution to address the conflicting problems of phosphorus pollution and scarcity. However, recovering organic phosphates, such as 1-hydroxyethane 1,1-diphosphonic acid (HEDP), is comparatively complex, which involves multiple processes. Herein, we developed an innovative all-in-one solution to simplify these processes by combining NiFe-layered double hydroxides (NiFe-LDH) and peroxydisulfate (PDS). This combination achieved approximately 90 % conversion of HEDP to orthophosphate, with 100 % of the resulting orthophosphate recovered in 120 min. The exceptional performance in simultaneous HEDP degradation and recovery can be attributed to dual roles of Ni and Fe in NiFe-LDH/PDS. The polyvalent Ni functions as an electron shutter (Ni2+ ⇋ Ni3+ ⇋ Ni2+) in the redox cycles between PDS and HEDP, accounting for effective HEDP degradation. The high complexation stability between Fe(Ⅲ) and orthophosphate (log K = 9.92) allows Fe(Ⅲ) to serve as binding sites for orthophosphate recovery. Moreover, NiFe-LDH/PDS effectively treats HEDP across wide pH ranges (3–––10), which can be ascribed to pH buffers originating from protonation/deprotonation in NiFe-LDH layers. The recovered phosphorus with NiFe-LDH exhibited a slow-release property under soil water solution without notable Ni release, which highlighted its potential usage as a slow-release fertilizer. These features—catalytic and binding sites, and high compatibility—allow NiFe-LDH to achieve concurrent degradation and recovery of organic phosphate in a single solution.

Multistage regulation of LiMn2O4 electrode for electrochemical lithium extraction from salt-lake

The sustainable development of future energy relies significantly on the abundant lithium resources present in salt-lake brines. LiMn2O4 (LMO) electrochemical Li+ pump has garnered substantial attention due to its capacity to efficiently extract lithium resources from aqueous solutions with minimal energy consumption. However, the industrial application of LMO electrodes is often limited by Mn dissolving during cycles, as well as the complex and variable brine environment. To address these challenges, this study conducted a multistage regulation of LMO electrodes. Originally, the sol-gel technique was used to prepare CePO4 loading LMO. Due to CePO4 rivet load reforming LMO surface charge, the best-performing 1 wt% CePO4-loaded LMO exhibited a remarkable capacity retention rate of 83.8 % after 30 cycles. Subsequently, a comprehensive hydrophilic modification was applied to the entire electrode. 20%PAA-1CP-LMO//Ag system displayed an admirably release capacity of 24.7 mg·g−1 in Zabuye real brine characterized by an ultra-low Li/Na ratio, with Li/Na ratio in recovery solution reaching as high as 0.62.

Solar-enhanced lithium extraction with self-sustaining water recycling from salt-lake brines

Lithium is an emerging strategic resource for modern energy transformation toward electrification and decarbonization. However, current mainstream direct lithium extraction technology via adsorption suffers from sluggish kinetics and intensive water usage, especially in arid/semiarid and cold salt-lake regions (natural land brines). Herein, an efficient proof-of-concept integrated solar microevaporator system is developed to realize synergetic solar-enhanced lithium recovery and water footprint management from hypersaline salt-lake brines. The 98% solar energy harvesting efficiency of the solar microevaporator system, elevating its local temperature, greatly promotes the endothermic Li+ extraction process and solar steam generation. Benefiting from the photothermal effect, enhanced water flux, and enriched local Li+ supply in nanoconfined space, a double-enhanced Li+ recovery capacity was delivered (increase from 12.4 to 28.7 mg g-1) under one sun, and adsorption kinetics rate (saturated within 6 h) also reached twice of that at 280 K (salt-lake temperature). Additionally, the self-assembly rotation feature endows the microevaporator system with distinct self-cleaning desalination ability, achieving near 100% water recovery from hypersaline brines for further self-sufficient Li+ elution. Outdoor comprehensive solar-powered experiment verified the feasibility of basically stable lithium recovery ability (>8 mg g-1) directly from natural hypersaline salt-lake brines with self-sustaining water recycling for Li+ elution (440 m3 water recovery per ton Li2CO3). This work offers an integrated solution for sustainable lithium recovery with near zero water/carbon consumption toward carbon neutrality.

Single-center pilot study of remote therapeutic monitoring in patients with operative spinal pathologies

ObjectivesSpine pathology affects a significant portion of the population, leading to neck and back pain, impacting quality of life, and potentially requiring surgical intervention. Current pre- and postoperative monitoring methods rely on patient reported outcome (PRO) measures and lack continuous objective data on patients' recoveries. Remote therapeutic monitoring (RTM) using wearable devices offers a promising solution to bridge this gap, providing real-time physical function data. This study aims to assess the feasibility and correlation between changes in physical function and daily activity levels using RTM for individuals with operative spinal pathologies. MethodsA single-center pilot study involving 21 participants with operative spinal pathologies was conducted at an academic hospital. Participants were provided Bluetooth-enabled Fitbit Inspire 2 activity trackers and asked to wear them daily for 100 days. The Healthcare Recovery Solutions (HRS) mobile application facilitated remote administration of the PROMIS - Physical Function Short Form 6b PROs questionnaire at days 1, 30, and 90. Linear regression, Students' paired T tests, and one-way ANOVA were used to analyze collected data. ResultsAverage compliance with RTM was found to be 82.4% compared to only 48% for PROMs. Changes in daily steps were moderately positively correlated with changes in PROs at both 30 and 90 days. Participant satisfaction with RTM was high, and responses indicated greater satisfaction with RTM compared to PROMs. ConclusionsRTM offers continuous and objective data collection, presenting a potential solution to the limitations of intermittent clinical assessments and self-reported outcomes. The study demonstrated a moderate correlation between changes in activity levels and changes in PROs, suggesting that RTM data could serve as a surrogate for PROs. Participants' high compliance and satisfaction with RTM underscore its feasibility and potential clinical utility. This study lays the groundwork for larger future investigations into the clinical benefits and broader application of RTM in spine care.

Oil Spill: Their Impact, Recovery and future prevention

An oil spill is the release of a liquid petroleum hydrocarbon into the environment especially marine areas due to human activity. Oil is the most common pollutant in the oceans. Oil spill have a devastating and long-term impact on water ways and coastal areas around the world. Oil spill can be partially controlled by chemical dispersion, combustion, mechanical containment and adsorption. These days there are so many import and export business are going in the world. Because of expansion of business and shipping by seas in the cheapest mode it’s used on large scale due to huge cargo shipping these are so many cases of oil spill in the sea. World has witnessed big oil spill accidents into the oceans and made huge impact on the industries as well as the ecosystem. Due to these oil spills there were so many deaths if sea mammals and bird species. After oil spills creates a slick (a thick layer of oil) that ensure the sunlight and oxygen pass through water. It affects the life below the water due to lack of oxygen and sunlight. As some of the oil are dangerous and poisonous they are quite harmful for human too when it comes to physical contact with them. This paper deals with the separation of oil and water to find out the better solution for oil recovery from the water surface mixture empress oil spill to produce oil free water. There are different methods to remove the oil form the water but disc type oil skimmer is mostly used and efficient. The oil skimmer is used to separate oil, from mixture of aqua and oil. It causes highly acidic alkaline and salty environment remains a great challenge to aquatic organisms and also pollute the coastal area. Every year 706 million gallons of waste oil enter the water resources and pollute the environment. Sea water has been polluted due to oil spillage, it also affects the water bodies. It the oil spill increase it result in serious damage to environment. About 90% of contaminated oil can be removed by continuous separation of oil by skimmer.

Stripe-schedule Aware Repair in Erasure-coded Clusters with Heterogeneous Star Networks

More and more storage systems use erasure code to tolerate faults. It takes pieces of data blocks as input and encodes a small number of parity blocks as output, where these blocks form a stripe. When reconsidering the recovery problem in the multi-stripe level and heterogeneous network clusters, quickly generating an efficient multi-stripe recovery solution that reduces recovery time remains a challenging and time-consuming task. Previous works either use a greedy algorithm that may fall into the local optimal and have low recovery performance or a meta-heuristic algorithm with a long running time and low solution generation efficiency. In this paper, we propose a Stripe-schedule Aware Repair (SARepair) technique for multi-stripe recovery in heterogeneous erasure-coded clusters based on RS code. By carefully examining the metadata of blocks, SARepair intelligently adjusts the recovery solution for each stripe and obtains another multi-stripe solution with less recovery time in a computationally efficient manner. It then tolerates worse solutions to overcome the local optimal and uses a rollback mechanism to adjust search regions to reduce recovery time further. Moreover, instead of reading blocks sequentially from each node, SARepair also selectively schedules the reading order for each block to reduce the memory overhead. We extend SARepair to address the full-node recovery and adapt to the LRC code. We prototype SARepair and show via both simulations and Amazon EC2 experiments that the recovery performance can be improved by up to 59.97% over a state-of-the-art recovery approach while keeping running time and memory overhead low.

New insights on antimony removal and recovery from water and wastewater using iron-coated cork granulates: Desorption on batch and fixed-bed column systems

This work investigated Sb adsorption–desorption using iron-coated cork granulates (ICG) in both batch and continuous modes to evaluate the materiaĺs adsorption and regeneration performance, as well as the possibility of antimony recovery. A fixed-bed column filled with ICG, demonstrated maximum adsorption capacities of 13 ± 2 mg g−1 and 10 ± 1 mg g−1 for Sb(III) and Sb(V), respectively, at pH 3. ICG was able to remove Sb within the WHO guideline of 20 μg/L at pH 6. Among the different classes of eluents tested for Sb(V) desorption, the acids achieved the highest desorption rates − 81 ± 9 % and 66 ± 8 % for HCl 1 M and ascorbic acid 0.1 M, respectively. The desorption kinetics showed that HCl 1 M reached equilibrium in 4 h, but ascorbic acid 0.1 M took 16 h. This work presents an ecological emerging solution for antimony removal and recovery from water and wastewater.

Performance study of an array piezoelectric energy harvester for pressure pulsation vibration energy in water hydraulic system

In this paper, an array piezoelectric energy harvester (APEH) is designed for energy collection from water hydraulic system. The APEH is arranged in a spatial axial array, exhibiting excellent insulation and waterproof properties. The effects of connection modes and pressure pulsation parameters on the output performance of APEH are investigated through theoretical analysis, simulation and experiment. The results show that the output electric energy of each piezoelectric disk is consistent, and it is generated by the deformation caused by pressure pulsation. The connection modes show significant differences at different resistances. Series and parallel connections have the same maximum output power. The parallel connection has a smaller optimal resistance and has advantages in practical engineering applications. Both the pressure amplitude and the pulsation frequency affect the output voltage and power and increasing the pulsation frequency leads to the decrease of optimal resistance. By employing parallel connection, APEH can achieve higher output at lower load resistances. When the resistance is 12 kΩ, the average power and power density are reach as 997.63 μW and 2.54 μW mm−3, respectively. In summary, the APEH proposed in this paper offering a viable solution for energy recovery in water hydraulic systems and the sustainable power supply of the sensors, along with providing relevant theoretical references and practical schemes.

Recycling of copper tailing as filler material in asphalt paving mastic: A sustainable solution for mining waste recovery

Copper tailings are a category of solid waste discharged after the beneficiation process in mining plants. The significant concern raising stringent environmental issues give impetus to explore the multi-channel utilization of copper tailings in a sustainable manner. Concerning the fact that no study has systematically compared properties of copper tailings filled (CTP) asphalt mastic with conventional limestone filler mastic (LP) at different filler-to-asphalt ratios, multiscale and multi-dimensional comparisons between the characteristics of CTP-asphalt and LP-asphalt mastics were made in this study to thoroughly explore the feasibility and potential of recycling CTP as alternative filler in asphalt materials. Four ratios from 0.3 to 1.2 were used to manufacture asphalt mastics. The in-service pavement performance of asphalt mastics including resistances to rutting, low-temperature cracking and moisture damage was explored. Finally, the environmental and economic perspectives regarding the recycling of copper tailings are analyzed. Results indicate that CTP possesses a rougher surface, a larger specific surface area, and a more uniform pore size distribution than LP, particularly across the mesopores range. These characteristics could promote the adsorption of asphalt on its particle surface, potentially leading to enhanced filler-particle interaction. Regarding pavement performance, CTP-asphalt mastic outperforms LP-asphalt mastic in terms of high-temperature performance. Meanwhile, its low-temperature performance and moisture stability are only limitedly declined with the acceptable performance. Further, heavy metals leaching tests suggest that the risk for the substantial utilization of CTP in paving asphalt is absent. The related outcomes have verified the promising potential of CTP as an alternative candidate to substitute the conventional filler in paving asphalt from comprehensive consideration of in-service performance, and environmental and economic benefits.

Molding the future: Optimization of bioleaching of rare earth elements from electronic waste by Penicillium expansum and insights into its mechanism

The recovery of rare earth elements (REE) from electronic waste is crucial for ensuring future demand security, as there is a high supply risk for this group of elements, and mitigating the environmental impacts of conventional mining. This research focuses on extracting REE from waste printed circuit boards through bioleaching, addressing the limited attention given to this source. A strain of Penicillium expansum demonstrated efficient bioleaching under optimal conditions of 7.5 initial pH, 0.1 mM phosphate concentration, and excluding a buffering agent. The study achieved significant improvements in La and Tb extraction and enhancements in Pr, Nd, and Gd recovery, approaching 70 % within 24 h. Fungal mechanisms involved in REE extraction included fungal pH control, organic acid biosynthesis, phosphate bioavailability, and potential fungal proton pump involvement. This approach offers a promising solution for sustainable REE recovery from e-waste, contributing to resource security and circular economy.

Semi-continuous mesophilic anaerobic digestion of date palm (Phoenix dactelifyra L.) leaflets of the H'mira cultivar from the Adrar region of Southern Algeria using an alkaline pre-treatment

This research paper aim to investigate the enhancement potential of mesophilic Anaerobic Digestion (AD) of Algerian date palm (Phoenix dactylifera L.) leaflets from H'mira cultivars using an alkaline pretreatment approach. The experiment was conducted for the first time in semi-continuous digesters. NaOH was applied at various percentages (6 %, 12 % and 18 %) to chemically pretreat the substrate for 5 days at 37 °C. The chemical pretreatment results were interpreted for the first time with in-depth FTIR spectroscopic analyses. The Hydraulic Retention Time (HRT) was fixed at 15 days, and the Organic Loading Rate (OLR) at 2 g MO/L/day. The results showed that the methane (CH4) production values were stabilized with a clear distinction at averages of 211.85, 177.26, 143.36 and 123.07 ml of CH4/day, i.e. a CH4 yield of 105.92, 88.63, 71.68 and 61.53 ml of CH4/gVS/day for the reactors containing substrates pre-treated with 12 %, 6 %, 18 % NaOH and the substrate without pre-treatment respectively. Compared to the substrate without pre-treatment, the CH4 production rates were improved 1.72, 1.44 and 1.16 times for the reactors containing 12 %, 6 % and 18 % NaOH respectively. These findings were perfectly in accordance with FTIR spectroscopy results. These findings demonstrate that the semi-continuous AD process can be an attractive energy recovery solution from such waste compared to batch digesters, (on one day, it produce 77–105 % of the CH4 produced during 21–55 days in batch digesters), as well as the importance of adequate pre-treatment prior to the AD. FTIR Spectroscopic analysis technology can also be widely used to analyze pre-treatment data for lignocellulosic biomass, as it gives very encouraging results.

Data recovery methods for DNA storage based on fountain codes

Today's digital data storage systems typically offer advanced data recovery solutions to address the problem of catastrophic data loss, such as software-based disk sector analysis or physical-level data retrieval methods for conventional hard disk drives. However, DNA-based data storage currently relies solely on the inherent error correction properties of the methods used to encode digital data into strands of DNA. Any error that cannot be corrected utilizing the redundancy added by DNA encoding methods results in permanent data loss. To provide data recovery for DNA storage systems, we present a method to automatically reconstruct corrupted or missing data stored in DNA using fountain codes. Our method exploits the relationships between packets encoded with fountain codes to identify and rectify corrupted or lost data. Furthermore, we present file type-specific and content-based data recovery methods for three file types, illustrating how a fusion of fountain encoding-specific redundancy and knowledge about the data can effectively recover information in a corrupted DNA storage system, both in an automatic and in a guided manual manner. To demonstrate our approach, we introduce DR4DNA, a software toolkit that contains all methods presented. We evaluate DR4DNA using both in-silico and in-vitro experiments.

EMB3Rs: A game-changer tool to support waste heat recovery and reuse

At a time when European countries try to cope with escalating energy prices while decarbonizing their economies, waste heat recovery and reuse arises as part of the solution for sustainable energy transitions. The lack of appropriate assessment tools has been pointed out as one of the main barriers to the wider deployment of waste heat recovery projects and as a reason why its potential remains largely untapped.The EMB3Rs platform emerges as an online, open-source, comprehensive and novel tool that provides an integrated assessment of different types of waste heat recovery solutions, (e.g. internal or external) and comprises several analysis dimensions (e.g. physical, geographical, technical, market, and business models). It has been developed together with stakeholders, and tested in a number of representative contexts, covering both industrial and heat network applications. This has demonstrated the enormous potential of the tool in dealing with complex simulations, while delivering accurate results within a significantly lower time-frame than traditional analysis.The EMB3Rs tool removes important barriers such as analysis costs, time and complexity for the user, and aims at supporting a wider investment in waste heat recovery and reuse by providing an integrated estimation of the costs and benefits of such projects. This paper describes the tool and illustrates how it can be applied to help unlock the potential of waste heat recovery across European countries.

Production of [211At]NaAt solution under GMP compliance for investigator-initiated clinical trial.

The alpha emitter astatine-211 (211At) is garnering attention as a novel targeted alpha therapy for patients with refractory thyroid cancer resistant to conventional therapy using beta emitter radioiodine (131I). Herein, we aimed to establish a robust method for the manufacturing and quality control of [211At]NaAt solution for intravenous administration under the good manufacturing practice guidelines for investigational products to conduct an investigator-initiated clinical trial. 211At was separated and purified via dry distillation using irradiated Bi plates containing 211At obtained by the nuclear reaction of 209Bi(4He, 2n)211At. After purification, the 211At trapped in the cold trap was collected in a reaction vessel using 15 mL recovery solution (1% ascorbic acid and 2.3% sodium hydrogen carbonate). After stirring the 211At solution for 1h inside a closed system, the reaction solution was passed through a sterile 0.22μm filter placed in a Grade A controlled area and collected in a product vial to prepare the [211At]NaAt solution. According to the 3-lot tests, decay collected radioactivity and radiochemical yield of [211At]NaAt were 78.8 ± 6.0 MBq and 40 ± 3%, respectively. The radiochemical purity of [211At]At- obtained via ion-pair chromatography at the end of synthesis (EOS) was 97 ± 1%, and remained > 96% 6h after EOS; it was detected at a retention time (RT) 3.2-3.3min + RT of I-. LC-MS analysis indicated that this principal peak corresponded with an astatide ion (m/z = 210.988046). In gamma-ray spectrometry, the 211At-related peaks were identified (X-ray: 76.9, 79.3, 89.3, 89.8, and 92.3keV; γ-ray: 569.7 and 687.0keV), whereas the peak at 245.31keV derived from 210At was not detected during the 22h continuous measurement. The target material, Bi, was below the 9 ng/mL detection limit in all lots of the finished product. The pH of the [211At]NaAt solution was 7.9-8.6; the concentration of ascorbic acid was 9-10mg/mL. Other quality control tests, including endotoxin and sterility tests, confirmed that the [211At]NaAt solution met all quality standards. We successfully established a stable method of [211At]NaAt solution that can be administered to humans intravenously as an investigational product.

Electro-induced biochar-embedded-SIPN hydrogel as discrete bipolar electrodes for selective oxidation and enrichment of trace thallium(Ι)

Electrochemical techniques for thallium (Tl) treatment face a substantial challenge linked to the concentration of Tl(I), hindering the efficient removal and recovery of trace Tl(I) (μg L−1). In response, we synthesized hydrogel particles incorporating biochar (BC) within semi-interpenetrating polymer networks (SIPN), showcasing robust selectivity for Tl(I). These biochar-embedded-SIPN hydrogel particles (BC-SIPN particles), employed as dispersed electrodes, facilitated the targeted oxidation and enrichment of Tl(I) through electro-induction. Research outcomes elucidate the adept mitigation of the “efficiency-dependent concentration” behavior by electro-induced BC-SIPN particles during the reaction process. Under optimized conditions (pH 12, 2 V cm−1, 30 min), Tl(I) removal efficiency surpassed 98 % at an initial concentration of 100 μg L−1. The SIPN structure enhanced particle stability, and after seven cycles of enrichment in a 100 μg L−1 Tl(I) environment, BC-SIPN particles achieved a Tl content of 0.073 %, meeting Tl mineral content standards and promoting the recovery of scarce Tl resources. First-principles calculations underscore the pivotal role of hydrogen bond-electrostatic interactions between TlOH(aq) and particles in driving selective Tl(I) adsorption. Insights from quenching and capture reactions reveal a predominant direct oxidation pathway of Tl(I) to Tl(Ⅲ), complemented by indirect oxidation driven by reactive oxygen species, including OH, O- 2 and 1O2. This study presents an innovative approach for trace Tl(I) wastewater treatment, simultaneously mitigating the “efficiency-dependent concentration” phenomenon, and underscores the transformative potential of electro-induced BC-SIPN hydrogel particles in offering sustainable solutions for Tl(I) removal and resource recovery in environmental stewardship.

Pyrolysis, a recovery solution to reduce landfilling of residual organic waste generated from mixed municipal waste

Despite policies to restrict the mixing of organic waste with other general waste and improve its separation at source, municipal solid waste still contains a high proportion of organic waste. The residual organic waste is generated as a by-product of the mechanical treatment of municipal solid waste (MSW) and is mainly disposed in landfills after composting. Its reuse and recovery status varies across European countries. Most countries restrict the use of biostabilised residual waste (BSRW) to landfill cover, whereas others have regulated it as marketable compost. Crucially, BSRW is set to lose its “recycled” status under the revised European Union waste framework, with probably tighter restrictions and increased costs imposed for the landfilling of organic waste. Our research aimed to investigate pyrolysis as an alternative technology to treat the 10–40 mm fraction of BSRW (representing 50% of BSRW generated). Pyrolysis at 700 °C was carried out and feedstock and pyrolysis products were characterized. Mass and energy balances showed that pyrolysis produced hot vapour/gas whose combustion may render the pyrolysis process energetically sustainable. Biochar comprises 30–50% of BRSW mass after removal of glass, metal and stones. Our results indicate that pyrolysis has the potential to create options for contributing to reduce the landfilling of BSRW; however, the presence of residual impurities may limit biochar applications.

Bisphosphonates activated keratin assembled nanoparticle targeting bone fracture for enhanced immunomodulatory and osteoinductivity

Bone fractures pose significant clinical challenges and require innovative solutions for effective treatment and rapid recovery. Nanoscale protein-based materials are prominent in biotechnology and biomedicine, demonstrating versatility in biological processes and drug delivery. Herein, we designed and fabricated self-assembled keratin nanoparticles via a bisphosphonate (BP)-activated conformation-conservative assembly process. We determined the structural properties of the nanoparticles and explored the immunomodulatory and osteoinductivity functions retained from keratin. In addition, the keratin-BP nanoparticles could repair bone fractures. This study on multifunctional self-assembled protein-drug nanoparticles provides useful baseline data for exploring novel therapeutic options for acute bone fracture and other diseases.

An integrated machine learning and metaheuristic approach for advanced packed bed latent heat storage system design and optimization

To tackle the challenge of waste heat recovery in the industrial sector, this research presents a novel design and optimization framework for Packed Bed Latent Heat Storage Systems (PBLHS). This features a Deep Learning (DL) model, integrated with metaheuristic algorithms. The DL model was developed to predict PBLHS performance, trained using data generated from a validated Computational Fluid Dynamics (CFD) model. The model exhibited a high performance with an R2 value of 0.975 and a low Mean Absolute Percentage Error (<9.14%). To enhance the ML model's efficiency and optimized performance, various metaheuristic algorithms were explored. The Harmony Search algorithm emerged as the most effective through an early screening and underwent further refinement. The optimized algorithm demonstrated its capability by rapidly producing designs that showcased an improvement in total efficiency of up to 85% over available optimized experimental PBLHS designs. This research underscores the potential of ML-integrated approaches in laying the groundwork for generalized design frameworks for TES systems, offering efficient and effective solutions for waste heat recovery.

Sensorless control of permanent magnet synchronous motor for exhaust energy recovery of internal combustion engine: a comparison between Kalman filter and MRAS observer

This paper deals with the sensorless control of a Permanent Magnet Synchronous Motor (PMSM) to be employed on a turbo-generator to recover the exhaust gas energy of an Internal Combustion Engine (ICE). The main problem with this application is the high rotational speed required by the exhaust gas turbo-generator. Indeed, this implies the difficulty of installing an encoder for speed measurement and control. For this reason, sensorless control is highly recommendable, but, on the other hand, the main sensorless techniques could fail in this peculiar situation because of the high computational effort required compared with the other sensorless applications. Moreover, a good knowledge of the model parameters is necessary. Therefore, the main goal of this paper is to compare two main sensorless techniques for rotational speed measurement, both in the deterministic framework (Model Reference Adaptive System (MRAS) observer) and stochastic framework (Extended Kalman Filter (EKF)), to verify their effectiveness, their computational load, their sensitivity against parameter variation and noisy measurements, and, finally, to present the best solution for the exhaust gas energy recovery from the internal combustion engine.