42 research outputs found

    Systems level roadmap for solvent recovery and reuse in industries

    Get PDF
    Recovering waste solvent for reuse presents an excellent alternative to improving the greenness of industrial processes. Implementing solvent recovery practices in the chemical industry is necessary, given the increasing focus on sustainability to promote a circular economy. However, the systematic design of recovery processes is a daunting task due to the complexities associated with waste stream composition, techno-economic analysis, and environmental assessment. Furthermore, the challenges to satisfy the desired product specifications, particularly in pharmaceuticals and specialty chemical industries, may also deter solvent recovery and reuse practices. To this end, this review presents a systems-level approach including various methodologies that can be implemented to design and evaluate efficient solvent recovery pathways

    Systematic Design, Optimization, and Sustainability Assessment for Generation of Efficient Wastewater Treatment Networks

    Get PDF
    Due to population growth and economic development, there has been an increase in global wastewater (WW) generation footprint. There are different technologies associated with the wastewater treatment (WWT) process. The challenge is to select technologies that minimize the cost of treatment, as well as meet purity requirements. Further, there is a need to integrate sustainability analysis to facilitate a holistic decision. With the application of systems engineering, sustainable and cost-effective solutions can be achieved. In this work, we apply systems engineering to generate a sustainable and cost-effective solution. A superstructure was generated by categorizing technologies into four treatment stages. After modeling all functional equations for each technology, an optimization problem was formulated to determine the best path for the treatment process. Mixed-integer non-linear programming (MINLP), which implements a 0–1 binary integer constraint for active/inactive technologies at each stage was used. Sustainability analysis was performed for each representative case study (municipal and pharmaceutical WWT) using the sustainable process index (SPI). The total cost of municipal WWT is 1.92 USD/m3, while that for the pharmaceutical WWT is 3.44 USD/m3. With the treatment of WW, there is a reduction of over 90% ecological burden based on the SPI metric

    Design of solvent-assisted plastics recycling: Integrated economics and environmental impacts analysis

    Get PDF
    In 2018, the United States generated over 35. 7 million tons of plastic waste, with only 8.4% being recycled and the other 91.6% incinerated or disposed of in a landfill. The continued growth of the polymer market has raised concerns over the end of life of plastics. Currently, the waste management system is faced with issues of inefficient sorting methods and low-efficiency recycling methods when it comes to plastics recycling. Mechanical recycling is the commonest recycling method but presents a lower-valued recycled material due to the material incompatibilities introduced via the inefficient sorting methods. Chemical recycling offers a promising alternative as it potentially allows for plastics to maintain their original properties. To that end, there is the need to investigate feasible chemical recycling methods to help mitigate the challenging problem posed by plastics at the end-of-life stage. This work proposes a conceptual solvent-assisted plastics recycling framework based on a superstructure optimization approach. This framework is evaluated using a representative case study to recover Polyethylene Terephthalate (PET). In this case study, it is found that polymer recovery is both economically and environmentally favorable when compared to traditional methods of disposal such as incineration

    Overview of preparedness and response to COVID-19 in Ghana

    Get PDF
    The Coronavirus disease 2019 (COVID-19) outbreak in Ghana is part of an ongoing pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). The first two cases of COVID-19 were confirmed in Ghana on 12th March 2020. COVID-19 was consequently declared a Public Health Emergency of National Concern, triggering several response actions, including enhanced surveillance, case detection, case management and contact tracing, closure of borders, suspension of international flights, ban on social gatherings and closure of schools. Preparedness and response plans were activated for implementation at the national, regional, district and community levels. Ghana’s Strategic approaches were to limit and stop the importation of cases; detect and contain cases early; expand infrastructure, logistics and capacity to provide quality healthcare for the sick; minimise disruption to social and economic life and increase the domestic capacity of all sectors to deal with existing and future shocks. The health sector strategic frame focused on testing, treatment, and tracking. As of 31st December 2020, a total of 535,168 cases, including 335 deaths (CFR: 0.61%), have been confirmed with 53,928 recoveries and 905 active cases. All the regions have reported cases, with Greater Accra reporting the highest number. The response actions in Ghana have seen highlevel political commitment, appropriate and timely decisions, and a careful balance of public health interventions with economic and socio-cultural dynamics. Efforts are ongoing to intensify non-pharmaceutical interventions, sustain the gains made so far and introduce COVID-19 vaccines to reduce the public health burden of the disease in Ghan

    Teaching sustainable design through simultaneous evaluation of economics and environmental impacts

    Get PDF
    The ever-increasing human population and industrial growth have posed a considerable burden on existing resources and have led to an increase in environmental pollution and climate change. The Engineering Clinics offered at the Henry M. Rowan College of Engineering at Rowan University is the hallmark of our program that enables our undergraduate students to actively participate in solving real-world problems through collaborative activities. Our graduate students get an opportunity to engage in stakeholder (i.e., industries, federal and regional funding agencies) interactions and student mentoring in conjunction with developing their research ability. Thus, through these synergistic undergraduate-graduate-faculty- stakeholder collaborations this work envisions to develop awareness about sustainable design and environmental impact in the community. The clinic problems include; (i) solvent recovery in process industries, and (ii) systematic synthesis of wastewater treatment (WWT) networks. These problems are important because imprudent use of industrial solvents and water resources have exacerbated the challenges relating to availability, quality as well as safe disposal of harmful solvents and wastewater. Through these challenging and relevant problems, we can teach our students multiple skills such as information collection, selective extraction of valuable content, economic and sustainability evaluation of multiple pathways through mathematical modeling, computer programming, technical writing, and presentation. The overall impact of these efforts is evident in the peer-reviewed conference and journal publications, oral and poster presentations at regional and national conferences, as well as our students choosing careers which value sustainability

    Effects of replacing fishmeal with black soldier fly larval meal in the diets of grower-finishing guinea fowls reared under tropical conditions

    Get PDF
    The study was conducted with the view to determine the impact of replacing fishmeal with black soldier fly larval meal (BSFLM) on growing guinea fowls. BSFLM replaced fishmeal (3% in the control diet) in the ratios of 0, 20, 40, 60, 80, and 100% to produce six dietary treatments, which were iso-caloric and iso-nitrogenous. Two hundred and forty-eight-week old guinea fowls with mean live weight of 273.2 ± 10.9 g were tagged, weighted, and randomly assigned to 24 (6 × 4) floor pens; each pen was treated as a replicate. Feed and water were provided ad libitum during the entire period, which lasted 10 weeks. Feed consumption differed among the treatment groups (P = 0.0072) with the 100% fishmeal diets recording the lowest. Daily gain was significantly (P = 0.009) higher for birds fed high BSFLM diets compared to the control (100% fishmeal diet). The inclusion of BSFLM in the diets elicited positive linear effect on weight gains of the guinea fowls (R2 = 0.91) with increasing concentration resulting in higher live weight gains. The feed conversion ratio (FCR) also differed between treatments (P < 0.05) but similar for the 100% fishmeal (control) and 100% BSFLM diets. Organ and haematopoitic integrity were equally assured regardless of levels of the protein sources fed to the birds. Generally, meats from birds fed 60 to 100% BSFLM and from hens were more acceptable. A study to evaluate the economics of utilising BSFLM in guinea fowl production is recommended

    Construct validity of the suboptimal health status questionnaire-25 in a Ghanaian population

    Get PDF
    Background The Suboptimal Health Status Questionnaire-25 (SHS-Q-25) developed to measure Suboptimal Health Status has been used worldwide, but its construct validity has only been tested in the Chinese population. Applying Structural Equation Modelling, we investigate aspects of the construct validity of the SHS-Q-25 to determine the interactions between SHS subscales in a Ghanaian population. Methods The study involved healthy Ghanaian participants (n = 263; aged 20–80 years; 63% female), who responded to the SHSQ-25. In an exploratory factor and parallel analysis, the study extracted a new domain structure and compared to the established five-domain structure of SHSQ-25. A confirmatory factor analysis (CFA) was conducted and the fit of the model further discussed. Invariance analysis was carried out to establish the consistency of the instrument across multi-groups. Results The extracted domains were reliable with Cronbach’s ɑ of 0.846, 0.820 and 0.864 respectively, for fatigue, immune-cardiovascular and cognitive. The CFA revealed that the model fit indices were excellent (RMSEA = 0.049 \u3c 0.08, CFI = 0.903 \u3e 0.9, GFI = 0.880 \u3c 0.9, TLI = 0.907 \u3e 0.9). The fit indices for the three-domain model were statistically superior to the five-domain model. There were, however, issues of insufficient discriminant validity as some average variance extracts were smaller than the corresponding maximum shared variance. The three-domain model was invariant for all constrained aspects of the structural model across age, which is an important risk factor for most chronic diseases. Conclusion The validity tests suggest that the SHS-Q25 can measure SHS in a Ghanaian population. It can be recommended as a screening tool to early detect chronic diseases especially in developing countries where access to facilities is diminished

    Spectrum of anxiety and depression reported in reproductive-aged women diagnosed with gynaecological disorders at a tertiary healthcare facility in Ghana

    Get PDF
    Background: Patients with gynaecological disorders often suffer from psychological disorders including anxiety and depression. Although depression and anxiety have been studied in Ghana, data regarding the prevalence of these disorders in patients with gynaecological disorders is non-existent. The aim of the study was to investigate the prevalence of anxiety and depression in reproductive-aged women diagnosed with gynaecological disorders.Methods: Cross-sectional observational study was conducted at the Gynaecology Clinic of Korle-Bu Teaching Hospital, a tertiary health facility in Accra, Ghana. Patients of reproductive age seeking gynaecological care at the facility from December 2018 to January 2019 were assessed for anxiety and depression using the Generalized anxiety disorder (GAD) questionnaire and the Beck depression inventory (BDI) respectively. Sociodemographic and clinical information was gathered as well.Results: Of the 120 patients interviewed (mean age 34.33±0.66), 36.7% were depressed while 51.6% were reported anxiety disorders. Patients aged 35-45 years had the highest prevalence of anxiety (24.58%) and depression (29.18%). Again, prevalence rates were highest among respondents with senior high school as the highest educational qualification, (anxiety (22.15%); depression (24.20%). Patients suffering from pelvic floor disorder recorded the highest prevalence of anxiety (11.40%) and depression (13.77%). There was a significant association between depression and gynaecological disorders [χ2(25) =53.915, p=0.001, CI=95%], but there was not enough evidence of an association between anxiety and gynaecological disorders [χ2(15) =22.791, p=0.089, CI=95%].Conclusions: Anxiety and depression are prevalent amongst women in their reproductive age diagnosed presenting with gynaecological disorders and there is a significant association between gynaecological disorders and the prevalence of depression

    Insights into Public Perceptions of Earthship Buildings as Alternative Homes

    Get PDF
    From MDPI via Jisc Publications RouterHistory: accepted 2021-08-18, pub-electronic 2021-08-25Publication status: PublishedSustainable futures necessitate a concomitant requirement for both sustainable buildings and sustainable behaviours under one roof. The defining principles behind Earthship buildings are to promote the use of local, recycled, waste, natural and renewable materials in their construction, for the adoption of a passive solar design for internal heating/cooling, collection of rainwater as a potable water supply, and encourage the onsite recycling of used water for plants to aid food production. However, despite growth in Earthship buildings constructed across many countries of the world, their appeal has not yet made a noticeable contribution to mainstream housing. Therefore, this study is the first to attempt to explore public perceptions towards the benefits and barriers of Earthship buildings as a means of understanding their demand by potential home builders/owners. Opinions were sought through questionnaire surveys completed by visitors to the Brighton Earthship building. Results reveal that the public believe that the reclamation of rainwater and greywater, renewable energy consumption and use of recycled materials included in the design/build are the major benefits of Earthship buildings, whilst the opportunity for a modern living style in a conservative lifestyle/setting, having a building that is cheaper than an ordinary home and the possibility of living totally off grid are considered the least beneficial reasons for building Earthship homes. Results also reveal that the public believe acquiring necessary permits/permissions to build may be more complicated, securing financial support (mortgage/loan) may be more challenging, and identifying/attaining suitable building plots are major barriers of Earthship buildings, whilst the futuristic/alternative building design, being built from waste materials and being entirely dependent on renewable resources (rainfall/wind/sunshine) are considered the least important barriers to building Earthship homes. Notwithstanding the participants included in this study already having an interest in Earthship buildings/lifestyles, it is concluded that the general public deem the general principles of Earthships as an acceptable choice of building/living but it is the formal means of building or buying an Earthship home that is the greatest hurdle against the uptake of Earthship buildings. Therefore, if sustainable futures are to be realized, it is proposed that a shift away from traditional house building towards Earthship building will require the involvement of all stakeholders immersed in the building process (architects, planners, builders, investors, lawyers) to path an easier journey for Earthship buildings and sustainable living

    Stakeholders' role in improving Ghana's construction safety

    Get PDF
    Health and safety (H&S) management has traditionally been the responsibility of the contractor. Most often, contractors are blamed for the accidents and other ill health that occur on their construction sites. H&S performance is, however, enhanced when there is effective collaboration between those involved in the construction process. This paper therefore explores the role of stakeholders in promoting construction H&S in Ghana through public works procurement. The four main stakeholders identified and evaluated in this study are the government, the client (employer), the contractor and the employee(s). Seven interviewees (comprising procurement managers, consultants and quantity surveyors) from public institutions in Ghana participated in the research. Data were collected using semi-structured interviews and were thematically analysed. Results indicate a conflict in the perceived functions and relation of these stakeholders in the construction process. To address the constraint to improving construction H&S, certain recommendations are offered. These include the identification of specific individuals responsible for supervision and employee training, the development of H&S policies by the government and contracts that clearly outline the contractual obligations of all parties involved. Additionally, the specific roles and involvements of other stakeholders in the procurement process in improving construction H&S are also outlined
    corecore