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Sustainability Assessment of Integrated Waste-to-Use Systems: A Case of Uganda
Get PDFFor countries like Uganda where organic waste composition accounts for at least 70% of the solid waste generated, collected, and disposed of at landfills and dumpsites, recovery of resources from the waste stream is crucial. This is because disposal of the waste in the landfills/dump sites exerts more pressure on land as a resource in addition to the environmental negative impacts associated with the degradation of the waste in the landfills, pollution of groundwater from leachate, generation of greenhouses gases, bad odor, and poor aesthetics. Moreover, given that the country also grapples with sewage and faecal sludge treatment and management due to the limited plants in place, alternative Waste-to-Use systems that promote resource recovery and management of various organic waste streams such as biowaste, animal manure, sewage/faecal sludge and wastewater could be a viable solution. The systems which consist of a combination of various technologies such as anaerobic digestion, incineration, landfilling, composting, and pyrolysis to produce briquettes boast of managing various organic waste streams and potential for application in various entities such as housing estates, towns/cities, at institutions. To assess the sustainability of such systems, multicriteria decision analysis was used. The results indicated that if trade-off of any aspect was considered i.e., technical, environmental, social, and financial, the Waste-to-Use systems were preferred i.e., a system consisting of composting and anaerobic digestion technologies. Also, a sustainability framework for the assessment of similar systems was proposed and it highlights the importance of involving stakeholders through the various stages such as, situation analysis, problem identification and definition, criteria and indictor selection, elicitation of scores and weight so that transparency in decision making can be boosted
Dynamic Analysis and Modeling Movement Transmission of Soil Construction Interaction
Get PDFThis paper defines the dynamic analysis and geometric demonstration of movement transmission and the dynamic soil-structure interaction using two different approaches: the finite component process and the limit component approach (EM). This mathematical process is an influential geometric approach right for dynamic tasks. In this item, we used very advanced and effective computer geometric converter approaches to study multifaceted difficulties. The fractional difference equation leading the motion is outcoming and resolved by EM. The influence of 3 dimensions on the movement transmission imitation (1D and 2D) has a conversed captivating effect, dependent on the different finite components kinds (triangles, rectangles, tall degree components). Geometric modeling of stifling is too discussed (Rayleigh checking). The finite component technique then treats a model of movement transmission owing to the vibration of a foundation. The limit component technique's capacities are remembered, and outcomes found through 2D and 3D mockups are planned. Numerous cases of dynamic soil-structure interaction (building, tunnel) are formerly pickled. The outcomes of these properties are discussed here
Age and Geochemical Characteristics of Nansu Rapakivi Granite in Jiaobei Uplift Belt, Qingdao
Get PDFLA-ICP-MS zircon U-Pb geochronology from Nansu large Rapakivi granite in the Jiaobei uplift belt shows the concordant age is 116.5±0.32Ma and the weighted average age is 116.7±0.89Ma, belonging to the late Yanshanian products of Early Cretaceous. The rock geochemical characteristics show that the SiO2 content of rapakivi granite ranges from 70.30% to 71.65%, with an average of 70.975%, A / CNK is 0.871 ~ 0.895 (average 0.883). K2O content is 4.70 ~ 5.75%, with an average of 5.14%, which is characterized by high potassium. Regarding trace elemental patterns, all the studied samples are enriched in large一ion-lithophile elements, e.g., K and Rb, and depleted in high-field-strength elements, e.g., Nb, Ta, and Ti. In terms of the chondrite-normalized rare earth element patterns, the Nansu samples are characterized by the strong enrichment of light rare earth elements (LREE) compared with heavy rare earth elements (HREE) and the absence of negative Eu anomalies. The Nansu ring porphyry granite is of high Sr and low Yb type, belonging to type I adakite, and formed in a high-pressure medium high-temperature environment of about 23km at depth and about 670oC. It is speculated that it was formed in the island arc environment and is related to the subduction of the Mesozoic Pacific plate
Overview of In-Situ Gelation Behavior of Gel Systems in Porous Media
Get PDFCross-linked polymer gel has been widely applied in profile control and water plugging due to its effective cost, wide suitability, excellent performance, and flexible gelation time. Previous research mainly focused on the bottle tests, reaction kinetics, and rheological properties of the gels, but the works of literature about the in situ gelations of gel placement in the porous media are relatively few. The study of the in-situ gelation behavior of gel systems is widely summarized in this paper, and the research tendency is proposed. The important practical questions, including the accurate lateral distance of gel placement, the variation of gel properties, and the injection pressure profile in the process of gel injection, should be resolved by laboratory and numerical research to enhance gel treatment success rate
Assessment of the Pollution of Soils Utilized for Growing Edible Plants in the DR Congo
Get PDFThis research was carried out with the aim to assess the pollution that threatens agricultural soils in urban areas in the Haut-Katanga region (DR Congo) by searching for heavy metals in the arable soil bordering the Kimpulande drain, in the nearby of the Shituru commune, the City of Likasi. This drain has been utilized since the 1930s by the Gécamines, the largest state-owned mining company in the country, to dispose of wastewaters from the copper and cobalt industry. The population living in Shituru utilizes the arable soil bordering the Kimpulande drain to grow edible plants. Based on the results from physicochemical analysis of soil samples from the first 40 centimeters and the determination of the spatial distributions of pH, electrical conductivity, and concentrations of selected heavy metals (Cu, Co, Cd, and Fe), it was concluded that the study area is composed of an alkaline soil (pH = 7.54) of which the average electrical conductivity is about 700 µS/cm. Unlike average concentrations of cobalt and iron, those of copper and cadmium have similar behavior, given that their average values decrease with soil depth. Besides, the soil utilized for urban agriculture of edible plants is polluted on the surface by cadmium (> 3 mg/kg) and copper (> 40 mg/kg). It is contaminated in depth by cadmium (> 1 mg/kg) and cobalt (from 20 up to more 100 mg/kg). This is not the case for copper and iron, given that their concentrations remained smaller compared to the limits set by the quality standards (QS) applicable to soils for agricultural use. Given the toxicity related to the presence in the arable soil of heavy metals to high concentrations, it was deduced that the Shituru in-force agricultural practices might result in the population's exposure to serious health problems. Consequently, the urban agriculture of edible plants on arable soils threatened by mineral pollution must be prohibited to protect the population's health
Recursive Estimation in the Moving Window: Efficient Detection of the Distortions in the Grids with Desired Accuracy
Get PDFThe development of fast convergent and computationally efficient algorithms for monitoring waveform distortions and harmonic emissions will be an important problem in future electrical networks due to the high penetration level of renewable energy systems, smart loads, new types of power electronics, and many others. Estimating the signal quantities in the moving window is the most accurate way of monitoring these distortions. Such estimation is usually associated with significant computational loads, which can be reduced by utilizing the recursion and information matrix properties. Rank two update representation of the information matrix allows the derivation of a new computationally efficient recursive form of the inverse of this matrix and recursive parameter update law. Newton-Schulz and Richardson correction algorithms are introduced in this paper to prevent error propagation and for accuracy maintenance. Extensive comparative analysis is performed on real data for proposed recursive algorithms and the Richardson algorithm with an optimally chosen preconditioner. Recursive algorithms show the best results in estimation with ill-conditioned information matrices
Fire Safety and Prevention Issues in Design of Tall Buildings
Get PDFFire safety design of tall buildings is crucial. The number of floors, the function, and the occupants' features build the complexity in the life and fire safety design of tall buildings. Because of the complexity of each tall building design, specific preventive measures are necessary more than the basic requirements given in the national and local codes. The fire safety design of the world-renowned tall buildings, including Guangzhou International Finance Centre (IFC), Capital Market Authority (CMA) Tower, and Jin Mao Tower are case studies and further focus is made on the facade design of tall buildings. The paper reviews the safety design issues and focuses on the fire evacuation models, estimations, and the effect of different parameters in the success of fire safety design of tall buildings. In addition to the various fire evacuation suggestions, the effect of human behavior in fire is also discussed through the literature review. Fire safety is not only an engineering problem to deal with, but also architects must know the holistic approach in the fire safety design of tall buildings since it involves their architectural design as well. The paper aimed to bring the most arguable issues in the fire safety design of tall buildings together and to highlight the value of different perspectives in achieving a promising fire safety design
Technologies for Halide Removal in Water Treatment – A State-of-the-Art Review
Get PDFHalides (X=Cl, Br, I) are naturally present in water, and halide concentrations can be high in water sources that are impacted by high salinity. Halides are also present in wastewater streams from various industrial operations such as pulp and paper, oil and gas, and mining. Drinking water guideline limits have been established for halides, and halide removal from water is important in several ways. Chloride concentration in water is more related to salinity, and its removal from water matters because of adverse health effects, water scarcity, corrosion, and industrial needs. In drinking water treatment, disinfection is essential to improve water quality and prevent the spread of water born pathogens. However, disinfectants also produce harmful disinfection by-products (DBPs) from precursors such as halides and natural organic matter (NOM) in the source water. Removing halides in the source water before disinfection is a preferred option to increase the disinfection efficiency and avoid forming more toxic DBPs. Some industrial-made isotopes are radioactive and carcinogenic, and iodide produces iodinated DBPs. Bromide removal is important because it produces brominated DBPs. Halides also affect AOPs and can cause more active radicals such as OH. and SO4-. to transform into less active radicals. This paper aims to comprehensively review the sources of halides, the chemistry, and interaction in forming DBPs, current regulatory limits and state-of-art removal technologies available, and their challenges
Experimental Evaluation and Development of Artificial Neural Network Model for the Solar Stills Augmented with the Permanent Magnet and Sandbag
Get PDFThe availability of potable water is reducing day by day due to rapid growth in the human population and un-planned industrialization around the globe. Although human beings cannot think of survival in the absence of water, the global leadership can still not implement their pacts in reality. Solar still is one of the prominent ways of getting potable water from contaminated water. This manuscript reports the experimental evaluation and developed ANN model for the single basin solar stills having augmentations with the sand-filled cotton bags and ferrite ring permanent magnets. Root mean square error (RMSE), efficiency coefficient (E), the overall index of model performance (OI), and coefficient of residual mass (CRM) values are in good agreement with the proposed developed model of ANN. The proposed ANN model can be utilized to predict distillate yield with a variation of 5% for the reported modified stills. Overall correlation coefficient of CSS, MSS-1&2 are 0.98171, 0.9867, and 0.99542, respectively
Enhanced Mechanism of Nano Zero-Valent Iron Activated Persulfate for Persistent Organic Pollutants in the Environment: A Critical Review
Get PDFThe advanced oxidation process based on persulfate has a broad application prospect in the remediation of organic pollutants. As an effective, low-cost and environmentally friendly material, nano-zero-valent iron (nZVI) can effectively activate persulfate (nZVI/PS) to generate strongly oxidizing sulfate radical for removing organic pollutants in the environment. In this review, we first clarify the activation pathway of nZVI activated persulfate including direct activation and indirect activation. Direct activation means that the electrons released by nZVI directly participate in the activation of PS; indirect activation means that Fe0 corrodes to generate Fe2+, and Fe2+ further activate the persulfate. Then, the mechanism of nZVI/PS system to degrade organic pollutants including electron transfer, hydrogen extraction and addition reactions are also discussed. Finally, combined with the activation pathway and the mechanism of degrading organic pollutants, we propose several prospects for the future research direction of nZVI activated persulfate. As a result, this review provides a theoretical basis for the nZVI/PS advanced oxidation system to remediate actual sites contaminated with organic pollutants