Search results for "WASTE"

Environment, wealth, inequality and the burden of disease in the Accra metropolitan area, Ghana

2005

The study examines environmental problems and adverse impacts on the health of urban households in the Accra metropolitan area, Ghana. Accra is faced with severe inadequacy of urban infrastructure in the face of rapid population growth in the metropolis. More than half of the city's population do not have access to solid waste collection services. Only 39.8% of households have indoor pipe and over 35.0% of households depend on unsanitary public latrines whilst 2.5% do not have access to toilet facilities. Human excrement, garbage and wastewater are usually deposited in surface drains, open spaces and streams in poor neighbourhoods. The resultant poor sanitation has serious health impacts as…

A Glance at the World

2016

Design methodology for submerged anaerobic membrane bioreactors (AnMBR): A case study

2015

[EN] The main objective of this study is to propose guidelines for designing submerged anaerobic MBR (AnMBR) technology for municipal wastewater treatment. The design methodology was devised on the basis of simulation and experimental results from an AnMBR plant featuring industrial-scale hollow-fibre membranes. The proposed methodology aims to minimise both capital expenditure and operating expenses, and the key parameters considered were: hydraulic retention time, solids retention time, mixed liquor suspended solids concentration in the membrane tank, 20 C-standardised critical flux, specificgas demand per square metre of membrane area, and flow of sludge being recycled from the membrane …

ENERGY RECOVERY FROM REGASIFICATION OF LNG

2012

The international forecasts on energy consumption in the next future show an increasing trend due also to growing markets, and among this the leading emerging economies connected to BRICS countries (Brazil, Russia, India, China and South Africa). We need more and more energy. On the other side the environmental problem is arising and the climate change is a more and more pressing emergency. The latest environmental disasters, as the oil spill in the Gulf of Mexico in 2010 and the earthquake with the following tsunami in Japan in 2011, struck the public opinion and so, as in many European countries, the nuclear program is under a deep revision or even stopped. So it is necessary to utilize a…

Cathodic reduction of CO2 to formic acid: Effect of the nature of the cathode for pressurized systems

2023

Electrochemical conversion of CO2 into formic acid (FA) in an aqueous electrolyte is considered a promising strategy to valorise waste-CO2. Some studies, mainly performed using Sn cathodes, have shown that the performance of the process can be strongly improved using pressurized systems. On the other hand, other studies, usually carried out in non-pressurized systems, have indicated that the nature of the cathode can strongly affect the process. Hence, in this work, we have investigated the coupled effect of nature of the cathode and CO2 pressure (PCO2 ) on the electrochemical conversion of CO2 to FA. Four electrodes (Sn, Sn/C-NP, Bi, Bi/C-NP) have been used as model cathodes. The results o…

Biogenic habitat shifts under long-term ocean acidification show nonlinear community responses and unbalanced functions of associated invertebrates

2019

Este artículo contiene 8 páginas, 4 figuras.

EPI-CT: design, challenges and epidemiological methods of an international study on cancer risk after paediatric and young adult CT

2015

Computed tomography (CT) has great clinical utility and its usage has increased dramatically over the years. Concerns have been raised, however, about health impacts of ionising radiation exposure from CTs, particularly in children, who have a higher risk for some radiation induced diseases. Direct estimation of the health impact of these exposures is needed, but the conduct of epidemiological studies of paediatric CT populations poses a number of challenges which, if not addressed, could invalidate the results. The aim of the present paper is to review the main challenges of a study on the health impact of paediatric CTs and how the protocol of the European collaborative study EPI-CT, coor…

Hand-made paper obtained by green procedure of cladode waste of Opuntia ficus indica (L.) Mill. from Sicily

2019

Cellulosic fibres have been obtained by green procedures from the cladodes of Opuntia ficus indica (L.) Mill., constituting a large agro industrial waste in our territory. The materials have been analysed for its relative composition, applying, IR and TG methodologies and it was characterised by the absence of lignin. The fibrous material allowed the manufacture of a handmade paper obtaining an ecological material suitable for packaging purposes. The authors evidenced that the simple protocol based on hot water treatment was able to decrease the amount of hemicellulose in the final material.

Ultrasound-assisted sequential extraction method for the evaluation of mobility of toxic elements in contaminated soils

2005

A method for the fast sequential extraction of toxic elements in contaminated soil samples using an ultrasonic water bath, followed by determination with inductively coupled plasma optical emission spectrometry (ICP-OES), was developed and compared with other methods introduced in the literature. The five-step sequential extraction (Tessier scheme) was shortened using ultrasound-assisted sequential extraction (UASE). The optimization of the five-step sequential extraction was based on the analysis of SRM 2710 using Tessiers’s method as a reference. Several extracting solutions with different sonication times and temperatures were tested in the optimization procedure. Concentrations of arsen…

Modelling Cd(II) removal from aqueous solutions by adsorption on a highly mineralized peat. Batch and fixed-bed column experiments

2006

This paper evaluates the potential use of a locally available organic soil amendment as a low-cost adsorbent. The removal of cadmium from aqueous solutions was studied by means of kinetic, batch and fixed-bed experiments. Batch experiments were conducted to evaluate the process kinetics and the removal equilibrium over a broad pH range. Pseudo-second-order kinetics and Freundlich equilibrium parameters were obtained. Six column experiments were carried out at different flow-rates and feed concentrations. Breakthrough curves showed higher metal retention than expected from the batch adsorption isotherms. Column modelling assuming rate-controlled pore diffusion was successfully performed. The…