Abstract

Water scarcity is a source of concern for modern society. This study analyzed the environmental performance of integrating conventional and upgraded technologies for water production. Life Cycle Assessment technique was applied for the impact categories of Primary Energy Demand, Global Warming Potential and Water Depletion for obtaining 1.0 m³ potable water. The results obtained from the individual analysis of each technology suggested that potable reuse is a promising alternative due to it has registered a lower Water Depletion than the other schemes, with equivalent performances for Primary Energy Demand (4.76 MJ/m³) and Global Warming Potential (155 gCO_2eq/m³). The best results of integrating technologies were obtained by the arrangement associating potable reuse and chemical treatment, with performances 65 to 67% lower than the other assessed compositions, depending on the water rate from potable reuse in the mix.

Abstract

Furfural, (Furan-2-carbaldehyde) is a potentially toxic substance. Indigenous bacterial strains naturally adapted to that contaminant were previously isolated from the effluent of a tannin industry and identified as Microbacterium sp., Bacillus licheniformis and Brevundimonas sp. The aim of this work was to determine the maximum concentration of furfural that can be degraded by bacterial consortium metabolism. The colonies were activated in peptone solution and then in a mineral medium with glucose as co-substrate, adding the bacterial consortium and different concentrations of furfural. They were incubated during 72 hours at 30 ºC and 200 rpm. Bacterial growth was monitored by measuring absorbance at 610 nm. The concentration of furfural was analyzed by High Performance Liquid Chromatography. The consortium was able to grow in furfural concentration of up to 4516 mg L^-1. Up to 2723 mg L^-1 can be degraded in 24 hours. According to these results, a considerable furfural consumption increase is possible with a consortium.

Abstract

Over the last years, stand-alone and / or hybrid photovoltaic systems have spread in rural areas especially in Sub-Saharan Africa. Compared to conventional systems (typically diesel generators), these systems can provide a reliable electricity supply at reasonable costs with low degree of greenhouse gas emissions. Therefore, this paper focuses on modelling and investigation of an off-grid photovoltaic system (charging station) performance based on a located in Kenya. However, the model can be adapted to any other region and any type of photovoltaic systems module by changing model input data such as solar radiation, air temperature, longitude, latitude, load profile and standard test conditions parameters of the photovoltaic systems module. The modelled photovoltaic system (charging station) will be used to provide reliable and clean electricity for a number of important tasks (e.g. water purification, charging special floatable lanterns and electric bikes).

Abstract

The steel industry is an important pillar of the Brazilian economy. However, as in other countries, the process consumes significant amounts of resources and generates sludge, slag and air emissions. In order to improve the environmental and energy feasibilities of Brazilian steel sector a Life Cycle Assessment was carried out to identify impact sources associated with it. The analysis pointed the coal consumption as the main source of primary energy demand, and high carbon dioxide emissions in steel production, oil refining and electricity generation as the origin of climate change impacts. Three improvement alternative were proposed to reduce impacts: S1: the use of steelmaking gas to produce electricity; S2: installation of dry coke quenching technology; and, S3: replacement of the manganese ore supply. A second round of assessments indicated that changes due to S1 and S2 brought only slight gains concerning impacts, but S3 resulted in improvement in metal depletion.

Abstract

Dissolved oxygen in Lam Takhong River gradually reaches zero value during the dry season on several occasions in the past decade causing the unsuitable quality for use as the raw water for Nakhon Ratchasima Town. Discharges of point sources and diffuse sources containing pollutants with organics and nutrients are the major cause of water quality deterioration in the river. To find the sources of impact on the water quality in the river, a one- dimensional steady-flow systems river water quality model, QUAL2Kw, was constructed and simulated. The model was calibrated and validated using the water quality data from 2008 to 2017 for the Lam Takhong River by seven monitoring stations. The modeling was applied to simulate various water quality parameters during the critical period to compare to the designated surface water quality criteria third class in Thailand (minimum dissolved oxygen at or above 4 mg/L; maximum biochemical oxygen demand, nitrate-nitrogen, and ammonia-nitrogen at or below 2.0, 5.0 and 0.5 mg/L, respectively). The study reach of the river flows 122 km from Lam Takhong Dam to the Mun River at Chaloem Phra Kiat district through the urban central area. Several segments of the river have been alarmed for many constituents with the dissolved oxygen impairment is the focus of the study. The scenarios of loads and upstream dissolved oxygen modification were conducted to assess the change of dissolved oxygen concentration. The result of the QUAL2Kw model showed that the decomposition of organic matter and a poor reaeration were the primary cause of the impairment. The local oxygenation causes fluctuations in dissolved oxygen levels along the river and the dissolved oxygen concentration decreases downstream of the river with some values fell the meet the fourth class of surface water quality criteria in Thailand (DO above 2 mg/L and BOD₅

Abstract

Machine learning models have proven to be reliable methods in classification tasks. However, little research has been conducted on the classification of dwelling characteristics based on smart meter and weather data before. Gaining insights into dwelling characteristics, which comprise of the type of heating system used, the number of inhabitants, and the number of solar panels installed, can be helpful in creating or improving the policies to create new dwellings at nearly zero-energy standard. This paper compares different supervised machine learning algorithms, namely Logistic Regression, Support Vector Machine, K-Nearest Neighbor, and Long-short term memory, and methods used to correctly implement these algorithms. These methods include data pre-processing, model validation, and evaluation. Smart meter data, which was used to train several machine learning algorithms, was provided by Groene Mient. The models that were generated by the algorithms were compared on their performance. The results showed that the Long-short term memory performed the best with 96% accuracy. Cross Validation was used to validate the models, where 80% of the data was used for training purposes and 20% was used for testing purposes. Evaluation metrics were used to produce classification reports, which indicates that the Long-short term memory outperforms the compared models on the evaluation metrics for this specific problem.

Abstract

The global energy demand is growing substantially. Clean and secure energy supply is a must for our civilization's sustainable development. Solar and wind energy is growing fast and can contribute significantly to meet the goals set by many countries to reduce greenhouse gas emissions.  A deep and wide investigation of the environmental impact of solar and wind energy is important before any solar or wind plants' construction is made.  In this study, the literature is reviewed to summarize the environmental impact of solar and wind energy systems in terms of the following factors; land use, water consumption, impact on biodiversity, visual and noise effects, health issues, and impact on micro climate. Although the benefits of solar and wind energy are obvious and great, negative perception of these technologies can inhibit their wide penetration in some regions. This review paper includes a critical and an inclusive analysis of solar and wind energy’s environmental impact and may serve as an important tool to conduct a proper environmental impact assessment. This critical analysis may serve also as a tool for developers, policy, and decision-when planning future solar and wind farms. 

Abstract

A deposit refund system of management of packaging waste offers a possibility to ensure sufficient quantities of secondary materials for the production of fully recycled packaging. Such market-based systems have proven themselves with large amounts of collected and recovered waste packaging with a small amount of impurities, but they tend to exhibit high costs if the system is not optimized. Ideally, such a system should operate on a non-profit basis. Therefore, economic drivers are identified and economic analysis, as well as modelling of deposit refund system, is conducted to determine overall system costs. Model is used on the case study of Croatia, in which the system is designed from the beginning, not considering previous developments but the most efficient system design elements. Regarding different costs and revenues of the system, it was calculated that the average fee that producers and importers of the beverage packaging pay for the operation of the system, in an efficient deposit refund system in Croatia would be 1.11 cents EUR per packaging unit (with the return rate of 85%).

Abstract

The purpose of this study is to introduce a methodology to identify optimal energy performance packages at the lowest cost during the estimated economic lifecycle for a residential building located in the Mediterranean climate. The method is applied to a detached single one-story building and calculations are performed for three climatic zones of Jordan which are relatively different from each other consider national factors. The energy conservation measures investigated are: dimming lighting control, building orientations, glazing type and its configurations, indoor conditions, upgrading heating, ventilation, air conditioning system, thermal insulation, and resident behavior. It was found that the optimum energy savings at the lowest cost are: 30%, 23%, and 39% for the reference building located in Irbid, Ma’an, and Aqaba respectively. The cost-optimal point is well identified in a hot climate. Based on the results, the climatic characteristics is a very important parameter affecting the reference building definition procedure. Based on the results, the methodology is highly sensitivity to national factors and utility rates and slightly sensitive to the discount rates, cost calculation period, and development price.

Abstract

Management of healthcare waste has gained wide attention in the recent years. This work reviews recent sustainable management of healthcare waste practices, the importance of legalizations, role of clinical waste producing bodies, emerging management trends, and treatment technologies. Furthermore, waste generated in the treatment processes and the health and environmental impacts of recent technologies are also examined. Sustainable assessment of technologies, to this point, revealed that in often cases, autoclave assisted with shredder could be a better alternative for the treatment of hazardous healthcare wastes while landfilling of healthcare waste received the lowest ranking. Studies are required to consider more reliable assessment methods for treatment technologies. This work can serve educators, researchers, as well as all the medical staff from nurses to doctors and volunteers who tirelessly contribute to the society in keeping people away from many diseases including the current global pandemic outbreak due to severe acute respiratory syndrome coronavirus 2 through the best and most sustainable practices in medical waste management.

Abstract

This paper develops policy measures for a “just transition” based on a case study conducted in Germany’s Rhineland lignite mining district. Semi-structured guided interviews served as the methodological approach. Expert interviews were conducted with representatives of citizen initiatives, trade unions and the Federal State of North Rhine-Westphalia. The results reveal the need for policy measures in different areas: First, employees working for subcontractors of the lignite industry have a high risk of losing their jobs because there are virtually no support policies for them. Second, there needs to be more input by civic initiatives regarding the process of structural change. And last, land needs to be prevented from becoming a scarce resource in the Rhineland area due to current mining legislation. We use an actor-centred institutionalist framework to derive governance approaches in line with the needs of various stakeholders.

Abstract

Decreasing the freshwater prices is considered a big concern within the desalination industry. The goal of this study is to determine the best reverse osmosis desalination system powered by photovoltaic or wind turbine in Ras-Gharib City, Egypt. The system is planned to produce 0.5 m³//hr of potable water. The techno-economic analysis is applied using SAM 2018.11.11 r4 simulation package. The results show that electricity bill using solar or wind energy is less than that in case of using convention energy systems. Based on simulation findings, the proposed photovoltaic system capacity is capable of generating water at a levelized energy cost of 3.95 cent$/kWh, compared to 9.5 cent$/kWh for wind system. The cost of one meter cubic of purified water using solar photovoltaic system is 0.08 $ while the cost is 0.19 $ using wind turbine system. Here, solar photovoltaic desalination system is the best choice system for this case study.

Abstract

High energy-intensive industries, including steel, chemicals, cement, and aluminium, contribute to about 75% of the industrial emissions of Carbon dioxide globally and expelling large amounts of unrecovered waste heat into the atmosphere. Yet there has been a challenge of studies that are conducted on recovering waste heat in the aluminium industry especially in cast-house facilities due to technical difficulties such as energy fluctuations in mass flow rate and temperature. In this study, waste heat to power system is designed to generate power and freshwater in a cast-house facility with 18 furnaces by evaluating three methods in which the temporal waste heat from holding furnaces can be damped and exploited. These methods are: (1) implementing a temporal air injection, (2) an optimization method for furnaces operation time shift, and (3) integrating sensible thermal heat storage. Organic Rankine Cycle is used for the waste heat to power conversion. The appropriate thermal energy storage design and a thermodynamic model of an Organic Rankine Cycle are investigated using a temporal flue gas data that is collected onsite from three furnaces. Reverse Osmosis technology is used to produce water using the generated electricity. Results show that sensible heat thermal energy storage is the most suitable technology for damping the waste heat. By utilizing waste heat from 18 re-melting furnaces, a net power output of 323 kW can be produced to operate a Reverse Osmosis plant supplying 2419 m³ of fresh water daily, saving up to 2000 metric tons of Carbon dioxide emissions annually. This study gives a comprehensive approach in dealing with temporal waste heat in aluminium furnaces for smooth cogeneration.

Abstract

Glaciers are humanity's most extraordinary reservoirs of water, covering approximately 10% of the total surface of the earth. The investigation of the retreat of the glacier surface in the Ampay National Sanctuary is carried out using the historical series of Landsat images and applies the normalized snow difference index between the years 1991 to 2017. To determine the situation of deglaciation and quantification from the retreat of Glacier Ampay, the meteorological data from the Tamburco and Abancay stations has been considered. The supervised classification spatial visualization method for the Landsat 2MSS image and the normalized snow difference index have been used to determine the glacier cover area with Landsat 5, Landsat 7 and Landsat 8 Operational Land Imagery /Thermal Infrared Sensor  images.  The results show a significant decrease in the surface of the Ampay glacier due to the increase in temperature. The surface of the Ampay glacier in 1991 has been 2.13 km² and in 2017 it has been 1.09 km², showing a loss of 1.04 km² (48.92%) in recent years as a consequence of significant climate variability (temperature and precipitation). In 2015, an apparent accumulation of snow was recorded on the Ampay glacier, reaching 2.595 km², but in the following years it has been decreasing until reaching 1.086 km² of the glacier surface in 2017. It is concluded that the glacial retreat of the Ampay National Sanctuary in the last 25 years it has been 1.04 km² with a tendency to continuous deglaciation, putting the water resource at risk.

Abstract

This study describes the development of an integrated design framework comprising technical, environmental, social, and economic modules to manage the design of communal wastewater treatment plant. It demonstrates a simple yet effective design management framework developed to tackle the challenges of incorporating Local Agenda 21 and the elements of triple bottom line reporting. The examined alternatives included stabilization pond, aerated lagoon, and biological contact oxidation treatment technologies with 1500 m³/day plant capacity. The integrated process facilitated comprehensive design and ensured the systemic and informed involvement of all relevant stakeholders. Environmental and technical criterion focused on reducing current impact on the aquatic environment in terms of nitrogen, ammonia, biochemical oxygen demand and suspended solids pollutants. Stabilization pond treatment was identified as the most appropriate solution to offer adequate treatment performance, simple and robust operability, and affordable user costs.

Abstract

The use of fixed or scheduled setpoints combined with varying occupancy patterns in buildings could lead to spaces being over or under-conditioned, which may lead to significant waste in energy consumption. The present study aims to develop a vision-based deep learning method for real-time occupancy activity detection and recognition. The method enables predicting and generating real-time heat gain data, which can inform building energy management systems and heating, ventilation, and air-conditioning (HVAC) controls. A faster region-based convolutional neural network was developed, trained and deployed to an artificial intelligence-powered camera. For the initial analysis, an experimental test was performed within a selected case study building's office space. Average detection accuracy of 92.2% was achieved for all activities. Using building energy simulation, the case study building was simulated with both ‘static’ and deep learning influenced profiles to assess the potential energy savings that can be achieved. The work has shown that the proposed approach can better estimate the occupancy internal heat gains for optimising the operations of building HVAC systems.

Abstract

Emergency response plans to mitigate the severity of the accidental release of hazardous compounds in the air have become a primary concern in view of the many adverse events occurred over the years in high-risk plants. To do this, an accurate estimate of forecast meteorological data to be used in dispersion models can be very useful to respond in advance to emergency situations. In this field, FORCALM is a new tool developed to elaborate European Centre for Medium-Range Weather Forecasts data on a 3D computational domain with a high-resolution grid. FORCALM data can be used to perform predictive simulations of impacts on local and regional levels by using CALPUFF modelling system. A case study relevant to an accident, occurred in the “Mediterranea” Refinery at Milazzo (Italy) in 2014, has been also examined for validation purposes. A comparison with results obtained by using CALMET modelling system and observed meteorological data, covering the area under study, is also described. The validation work has allowed confirming that predictive assessments, carried out with the help of FORCALM, lead to information regarding potential environmental impacts with a good degree of accuracy.

Abstract

An energy performance study of a building using the Montenegrin and European Standard on Energy Building Performance and the RETScreen software to compare the results from analysis for a one chosen hospital building is presented. In this study, the appropriate mathematical model of calculation is performed for the purpose of the analysis, using Excel software and algorithm which has been proposed by the above mentioned standard (the monthly method). The inspection of the current conditions of hospital building in Prizren, Kosovo is done and energy efficiency measures are proposed for improving the conditions of stay. All data are collected and gained through the inspection, and calculations are performed for existing and proposed condition of the building. The obtained results for both models are compared and show that most of the energy indicators have small differences in percentage among each other. There is a difference in carbon dioxide emission reduction between two models, due to the fact that calculations with the European standard resulted in the need of higher energy for cooling after the energy efficiency measures (14.75 megawatt hour), and considering that the source of energy for cooling is electricity, in terms of the Carbon dioxide equivalent emission, this means 21.21 tons Carbon dioxide equivalent, more to be emitted after the energy efficiency measures.

Abstract

The need for an energy transition is nowadays undeniable. Climate change, fossil fuel depletion and economic vulnerability are some of the main drivers of the model change. Therefore, it is necessary to promote local energy generation in order to improve a renewable energy transition. This paper presents the design, installation and performance of an Underwater Turbine Generator prototype with a gravitational vortex and siphon. The development of the prototype was done in five stages: contextualization, specifications, conceptualization, detail design and manufacturing. The result of this research is an appropriate, compact and low-cost prototype with a power range of 2 to 10 kW and head of 0.8 to 3 m. According to field measurements, the efficiency of a 7.5 kW generator for heads differences larger than 0.8 m is 37%. This type of design can be reproduced in another context in order to promote the decentralized generation and sustainable growth between the territory and its resources.

Abstract

Increased separation of food waste driven by the European Circular Economy Action Plan will create a need for establishing new treatment plants that can turn waste resources into high value products. This paper presents a real example of how life cycle assessment was used as decision support when establishing a new anaerobic digestion plant in Norway. The aim of the paper is to investigate the accuracy of the results of the predictive study performed before the plant was built by comparing them with results from the operation of the plant. The comparative assessment revealed that both the burdens and avoided emissions were underestimated. The production volume of upgraded biogas as a fuel for transport was higher than anticipated, resulting in a higher benefit than expected associated with substitution of diesel. Conversely, the impacts from transport and from the anaerobic digestion process were higher than forecasted. In total the net results from the predictive study were within an acceptable range compared with results based on real data.