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Efficacy of aerobic granular sludge treatment of piggery wastewater under length regulation of truncated modified basalt fibers
Get PDFAerobic granular sludge (AGS) technology offers several advantages over traditional activated sludge systems; however, its performance can be unstable when treating wastewater with high organic and ammonia loads. Truncated modified basalt fibers (TMBF) have been demonstrated to enhance the stability of AGS systems when treating piggery wastewater (PWW), but little is understood about their impact. In this study, the addition of TMBF with lengths ranging from 0.1 to 0.4 mm significantly accelerated sludge granulation, achieving complete granulation in 10 days compared to 17 days in the control reactor. The enhancement was attributed to increased secretion of β-polysaccharides, resulting in smaller cavities within the granules for the 0.1 mm TMBF. In contrast, 0.2 mm TMBF promoted the secretion of proteins, hindering substrate transfer and reducing ammonia oxidation efficiency. The addition of 0.1 mm TMBF resulted in chemical oxygen demand (COD) and ammonia removals of 90.7 % and 96.8 %, respectively. Furthermore, the addition of TMBF enriched the sludge with a substantial number of functional bacteria, Thauera and Chryseolinea, which were the most abundant genus, contributing to its stable pollutant removal efficiency. These findings provide key insights on potential strategies for optimizing AGS technology to treat industrial wastewater that has high ammonia and COD loads, not usually suited for intensified AGS systems.Cranfield University, 2023 M741423Open Project of the State Key Laboratory of Urban Water Resource and EnvironmentOpen Project of State Key Laboratory of R&D program of Zhenjiang (No. SH2021008)Key Research and transformation program of Qinghai province (No. 2022-SF-137)China Postdoctoral Science Foundation (No. 2023 M741423)Youth Program Natural Science Foundation of Jiangsu Province (No. BK20230552)Pre-research Fund of Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment (XTCXSZ2020-4)Journal of Water Process Engineerin
Optimisation of the human solid waste treatment system to manage outputs in compliance with the ISO 30500
No full textOzmen, Serap - Associate SupervisorNearly half of the world’s population is still struggling with inadequate sanitation,
especially where sewer systems are lacking. Non-sewered sanitation systems
offer a sustainable alternative for human solid waste treatment. This research
explores the torrefaction process for treating the solid fraction of human excreta.
The study investigated the impact of torrefaction temperature and retention time
on the quality of the solid char and liquid outputs through a series of experiments.
Char quality was assessed using proximate and elemental analyses to determine
composition, along with pathogen reduction tests for E. coli and C. perfringens.
For the liquid output, chemical analyses were performed, including COD, TSS,
TP, TN, and pH analysis.
Results demonstrated that increasing torrefaction temperature from 150°C to
200°C resulted in a reduction of moisture content from 14% to 3% and a decrease
in pathogen levels. As the temperature change was relatively small, there was
small difference in elemental composition. Treatment at 250°C with 0.083 RPM
resulted in a biochar with excellent terrified properties, including low moisture
content (5%), increased hydrophobicity, improved grindability, and nearly full
eradication of E. coli (<10 MPN/g). A novel rheology chart (RhS-0 to RhS-7) was
developed to classify torrefied char based on its progressive transformation,
including colour change (light brown, brown to black), increasing hydrophobicity,
decreasing moisture and rising fixed carbon levels. This chart addresses a
significant research gap by providing a systematic classification of torrefied char,
a previously underexplored area. These findings contribute to advancing
sustainable waste treatment technologies by providing a decentralised sanitation
solution that aligns with ISO 30500 standards.
Gates Foundation – INV - 053587MSc by Research in Desig
How to find opinion leader on the online social network?
Get PDFOnline social networks (OSNs) provide a platform for individuals to share information, exchange ideas, and build social connections beyond in-person interactions. For a specific topic or community, opinion leaders are individuals who have a significant influence on others’ opinions. Detecting opinion leaders and modeling influence dynamics is crucial as they play a vital role in shaping public opinion and driving conversations. Existing research have extensively explored various graph-based and psychology-based methods for detecting opinion leaders, but there is a lack of cross-disciplinary consensus between definitions and methods. For example, node centrality in graph theory does not necessarily align with the opinion leader concepts in social psychology. This review paper aims to address this multi-disciplinary research area by introducing and connecting the diverse methodologies for identifying influential nodes. The key novelty is to review connections and cross-compare different multi-disciplinary approaches that have origins in: social theory, graph theory, compressed sensing theory, and control theory. Our first contribution is to develop cross-disciplinary discussion on how they tell a different tale of networked influence. Our second contribution is to propose trans-disciplinary research method on embedding socio-physical influence models into graph signal analysis. We showcase inter- and trans-disciplinary methods through a Twitter case study to compare their performance and elucidate the research progression with relation to psychology theory. We hope the comparative analysis can inspire further research in this cross-disciplinary area.USAF OFSR|FA8655-20-1-7031The work is supported by "Networked Social Influence and Acceptance in a New Age of Crises", funded by USAF OFSR under Grant No.: FA8655-20-1-7031, and is partly supported by the Engineering and Physical Sciences Research Council grant number: EP/V026763/1.Applied Intelligenc
Numerical modelling on metallic materials
Get PDFThis article belongs to the Topic Numerical Modelling on Metallic MaterialsNumerical modelling of metallic materials has emerged as a pivotal research area in modern materials science and engineering [...]Metal
Chlorate occurrence in drinking water
Get PDFJarvis, Peter - Associate SupervisorThe use of chlorine for disinfection of potable water has been the major public
health advancement in the last century. Sodium hypochlorite is currently used
worldwide for potable water disinfection. Arising from sodium hypochlorite
solutions, chlorate forms as the sodium hypochlorite ages. Chlorate has been
recently regulated in the EU directive and is catalogued as a compound of
concern for the Drinking Water Inspectorate. The WHO recommended in 2015 a
guideline level of 0.7mg/L, and chlorate is currently set at level of 0.25 mg/L in
potable water supplies. As chlorate was previously a guidance, and not
extensively monitored, this presents a regulatory challenge for most water
companies to adopt.
From a large historical data set, from 2014 to 2020, it was extrapolated that
chlorate monthly running average values were expectedly higher during the
warmer season, likely explained by the increased chlorine demand during
warmer months, but far from the current regulation limit for well-resourced sites.
A questionnaire was completed in cooperation with operators and process
scientist on site. The interviews were completed across various WTW in Scotland.
The aim was to demonstrate the varying disinfection practices and extract
conclusions on the hypothetical chlorate levels arising during the dosing and
storage of sodium hypochlorite. The selection of sites provided a good overview
on the particularities of the disinfection stage, from small WTW, where the sodium
hypochlorite gets diluted on site, to large WTW with bulk storage of 15% sodium
hypochlorite. Sites with a varied risk of chlorate occurrence were also included
such as on-site electro-chlorination and chlorine gas disinfection.
It was concluded that there are correct measures in place during the operation
and maintenance of the disinfection stage, but chlorate levels during storage are
not centrally reported. The questionnaire has shown some sites where the
solutions of sodium hypochlorite were potentially exposed to warm temperatures
and extended periods of storage. It is likely that high room temperature is the
underpinning cause leading to sudden chlorate increase in combination with high
chlorine demands during the warmer months. This emphasised the need for
longitudinal studies on the degradation of hypochlorite solutions during storage.
It has been identified that a robust supply chain providing fresh hypochlorite
deliveries could be a major implementation aiming to tackle high chlorate levels,
particularly for remote and isolated potable water treatment works. The need for
an accurate determination of chlorine demand on site remains of crucial
relevance aiming to adjust disinfectant capability across varying treatment
processes. The importance of regular procurement of hypochlorite solutions and
the need for contingency was emphasised by the operators in order to avoid high
seasonal chlorate levels.
As a part of the experimental plan, the aim was to analyse the long-term stability
of sodium hypochlorite during storage with a focus on the impact of disinfectant
concentration on chlorate formation. The decay rates for sodium hypochlorite
solutions and chlorate formation have been determined at varying initial
concentrations using incubation experiments in the laboratory. It was determined
the application of consecutive refilling during sodium hypochlorite storage with
remaining old solutions of hypochlorite. Via bench scale kinetic experiments, it
was determined whether the use of a 10% free chlorine concentration of sodium
hypochlorite is less prone to promote further chlorate formation compared to the
currently used 15% hypochlorite solutions. It has been found the relative chlorate
to free chlorine content remains high even after the adoption of lower
concentration hypochlorite solutions. This has implications for sites currently
using dilution of hypochlorite and high chlorine demands. Lower initial
concentrations of sodium hypochlorite also presented more stability and
remaining disinfectant capacity during the bench scale studies. It is concluded
that extensive monitoring and control will be required in order to achieve tighter
chlorate standards.
The relative chlorate to free chlorine ratio (mg Chlorate/ mg of free chlorine) has
been highlighted as a concern resulting from high values in diluted solutions of
hypochlorite and on-site electro chlorination systems. Further mitigation
strategies have been summarised discussing the risk factors for future chlorate
occurrences, implementations aiming to tackle chlorate occurrence preemptively, and limit exceedances of the EU directive, now adopted in Scotland.
Overall, the thesis provided a better understanding on the drivers prompting
chlorate levels derived from sodium hypochlorite disinfection, a list of
comprehensive evidence-based interventions at water treatment facilities and
highlighted best management practicesPhD in Water, including Desig
Influence of notch geometry and temperature on the mechanical properties of Al‐Mg alloy using molecular dynamics simulations
Get PDFAt the near‐threshold regime, small irregularities on the surface can interact with the microstructure and affect the nucleation and propagation of cracks. Molecular dynamics is an effective methodology to investigate the damage evolution at this scale, and three types of defects, namely, triangular, rectangular, and crack, are examined. The effects at different temperatures (10, 300, and 450 K) and depths (2, 4, and 8 nm) are investigated in an aluminum alloy containing 5% magnesium. Cracks propagate via amorphization of the crack tip and, at low temperatures, also through the formation of voids. Elevated temperatures and deeper pits reduce the mechanical strength of the materials, increasing the radius of amorphization, while the effect of the shape on the mechanical properties is negligible. The observed behavior follows a trend observed experimentally and through finite element modelling in the literature, extending the results from the macroscale to the microscale.Fatigue & Fracture of Engineering Materials & Structure
Integrating blockchain with digital product passports for managing reverse supply chain
No full textThe evolution of the circular economy has led to the adoption of circular supply chains, where efficient management of the reverse supply chain enhances resource utilization, minimizes waste, and fosters a circular supply chain. However, managing reverse supply chains presents numerous challenges including a lack of information transparency and traceability, inconsistent cooperation among stakeholders, and uncertainty in recycling process, such as variations in quantity, quality, and timing. To address these challenges, an information sharing framework that integrates blockchain technology with digital product passports (DPPs) is designed to manage reverse supply chain information. Subsequently, a system dynamics model is applied to evaluate the potential impacts and feasibility of this framework within the reverse supply chain and its implications for the forward supply chain. The results indicate that the application of the proposed framework enhance the legal recycling market, reduces the negative environmental impact of illegal recycling activities, mitigates the bullwhip effect within the forward supply chain, and improves market fulfillment rate. The proposed information sharing framework can be employed to enhance the information efficiency of the reverse supply chain, aid in the recovery of end-of-life products and critical resources utilization, thereby supporting the transition to a circular economy.Transportation Research Part E: Logistics and Transportation Revie
The applications of IoT network to enhance farming at Al-Aziziah Palm Trees Farm in Saudi Arabia
Get PDFThis paper explores the use of Internet of Things (IoT) technologies to reduce high water consumption and attached operational costs in date palm farming at Al-Aziziah Palm Trees Farm in Hail, Saudi Arabia. Conventional irrigation practices often lead to inefficient water use and elevated expenses, particularly from the diesel-powered water pumps. To overcome this, an on-farm living lab was deployed using Internet of Things (IoT) network for real-time sensor monitoring, where collected data is analysed using cloud analytics to enable data-driven decision-making with enhanced water efficiency. Findings demonstrate that this IoT-based system can significantly enhance irrigation accuracy for 45% reduction in water pump usage, and consequently, a notable decrease in diesel fuel consumption. The cost model developed in this study estimates significant potential savings per year. This paper presents a replicable framework for deploying IoT technologies in large-scale date palm farms, promoting economic and environmental benefits of sustainable farming practices in Saudi Arabia and similar arid regions.Smart Agricultural Technolog
Unveiling the synergy of sustainable manufacturing practices and lean for sustainable manufacturing competitiveness
No full textThe present study investigates the integration of Lean and Sustainable manufacturing (LSM) practices to improve the market competitiveness of Indian manufacturing organizations. The study aims to explore the critical role of stakeholder commitment to drive both sustainable manufacturing and lean practices with their impact on manufacturing competitiveness. In the study a survey-based approach was used, the data was collected from 152 Indian manufacturing firms and analyzed using Principal component analysis (PCA) and Structural equation modelling (SEM) approach with IBM SPSS and AMOS software. The sampling approach focused on the consideration of medium and large enterprises of India across various sector using the structure questionnaire to assess the key constructs such as: stakeholder commitment, lean practices, and sustainable manufacturing. The result of the study reveals that stakeholder commitment significantly influences the adoption of both sustainable and lean manufacturing practices which help to drive manufacturing competitiveness. The SEM analysis conducted in the study reveals that there is structural relationship between the variables which further provides the evidence that organization ability to integrate lean and sustainable manufacturing practices improves the market competitiveness in dynamic business environment.Discover Applied Science
Analytical modeling and experimental validation of wear and frictional noise under lubricated conditions
Get PDFUnderstanding the dynamics of friction, wear, and noise under lubricated conditions is crucial for the predictive maintenance of mechanical systems; however, existing models often overlook the role of lubrication in modulating these interactions. This research presents an analytical model that combines single-degree-of-freedom (SDOF) vibration theory, Hertz contact mechanics, the Archard wear model, and the principles governing acoustic emission to predict both wear depth and sound pressure level emitted in a lubricated pin-on-disc system. Contact stiffness and wear-induced geometric changes are dynamically updated by the model, considering viscous damping from thin-film lubrication. Experiments were conducted using an Anton Paar TRB3 tribometer under lubricated conditions at realistic loads of 15, 20, and 30 N and a rotational speed of 300 rpm (corresponding to a linear sliding velocity of approximately 0.314 m/s at a 10-mm track radius). The friction noise was recorded by a microphone that was free-standing. The analytical predictions were closely aligned with the measurements taken during the tests. For mild steel, wear depth errors remained below 22%, while sound pressure predictions deviated by 14–21%. Due to its softer nature, aluminum exhibited higher wear deviations (up to 32%). Track analyses showed that lubrication decreases wear depth compared to dry sliding, and sound pressure levels are closely related to wear depth. Track analysis revealed that lubrication decreases wear depth by up to 50% compared to dry sliding, and sound pressure levels closely follow wear progression. This work improves prognostic health management systems by incorporating lubrication dynamics and tribo-acoustic phenomena, which allow for effective real-time wear and noise monitoring in industrial applications.Journal of Tribolog