Search results for "S.E.M."
showing 10 items of 5492 documents
Sea water desalination and energy consumption: A case study of wave energy converters (WEC) to desalination applications in sicily
2016
Recent studies about interactions among energy and water are considered as a new field of research. As almost all energy generation processes require significant amounts of water, and water requires energy for treatment and transport, so these two resources are inextricably linked. The main aim of this work is a presentation of the use of renewable energy for desalination plants in Sicily: in particular exploitation of wave energy into electrical energy necessary for water treatment. Desalination is the most energy intensive water treatment technology but it could be solution for many problems in water supply for areas with chronic debt of water. The aim of this work is a description of a s…
To incinerate or not? - Effects of incineration on the concentrations of heavy metals and leaching efficiency of post-precipitated sewage sludge (RAV…
2020
The major element and heavy metal concentrations of post-precipitated sewage sludge (PPS) and its ash residue (PPA) were determined using microwave digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS). To the best of our knowledge, this has not been previously done. In both PPS and PPA the heavy metal concentrations were clearly below the average concentrations than those encountered in sewage sludge in Europe. The leaching efficiency of the metal (Al/ Fe) used as a precipitation agent from post-precipitated sludge and its ash residue with phosphoric acid was also investigated with previously optimized leaching conditions. T…
A new strategy to maximize organic matter valorization in municipalities: combination of urban wastewater with kitchen food waste and its treatment w…
2017
[EN] The aim of this study was to evaluate the feasibility of treating the kitchen food waste (FW) jointly with urban wastewater (WW) in a wastewater treatment plant (WWTP) by anaerobic membrane technology (AnMBR). The experience was carried out in six different periods in an AnMBR pilot-plant for a total of 536 days, varying the SRT, HRT and the food waste penetration factor (PF) of food waste disposers. The results showed increased methane production of up to 190% at 70 days SRT, 24 hours HRT and 80% PF, compared with WW treatment only. FW COD and biodegradability were higher than in WW, so that the incorporation of FW into the treatment increases the organic load and the methane producti…
A comprehensive comparison between halophilic granular and flocculent sludge in withstanding short and long-term salinity fluctuations
2018
The effects of salinity fluctuations on the activity of autochthonous halophilic bacteria in aerobic granular sludge (AGS) and flocculent activated sludge (FAS) reactors were investigated. The response of nitrifiers and denitrifiers activity to drastic and moderate salinity shocks in the short-term (ST) and long-term (LT) was examined. The BOD5removal efficiency decreased only in the reactors subjected to the drastic LT salinity increase. Nevertheless, stable performances were achieved 18 days after the shock in the AGS-R1 (90%), whereas after 27 days in the FAS-R1 (82%). The loss in nitritation efficiency was higher in the FAS reactors and was proportional to the shock intensity. Nitritati…
Waste activated sludge dewaterability: comparative evaluation of sludge derived from CAS and MBR systems
2016
Nowadays, sludge dewatering is one of the greatest operational cost to wastewater treatment cycle. Specifically, 1t of fresh sludge to be disposed is composed, on average, by 0.25 - 0.30t of suspended solids, with an average cost for treatment and disposal around 280 - 470 €/t of suspended solids. Despite several technologies have been developed with the focus to reduce also the specific sludge production, still mechanical dewatering represents a crucial step to limit the amount of sludge to be disposed. Many physical–chemical parameters influence the sludge dewaterability: floc structure, particle size, bound water content, surface charge and hydrophobicity, Extracellular Polymeric Substan…
Analysis of uncontrolled phosphorus precipitation in anaerobic digesters under thermophilic and mesophilic conditions.
2019
This study compares the operation of mesophilic and thermophilic anaerobic digestion of sewage sludge and their effects in uncontrolled phosphorus precipitation. The research has been carried out using a pilot plant consisting of two digesters of 1.6 m3 working volume, treating the mixed sludge of Alzira WWTP (Valencia, Spain). The digesters were operated in parallel, at different conditions: mesophilic (38 ± 2.0°C) and thermophilic (55 ± 2.5°C) temperatures and organic loading rates (OLR) ranging from 1.1 to 1.7 kg volatile solids (VS) m−3 d−1 and different hydraulic retention times (HRT) 20, 15 and 12 days. Uncontrolled precipitation was evaluated through P, Mg and Ca mass balances in bot…
Occurrence of antibiotics and antiretroviral drugs in source-separated urine, groundwater, surface water and wastewater in the peri-urban area of Chu…
2020
Recently, there has been an increased interest in bridging the knowledge gap in the occurrence and fate of pharmaceuticals in African urban water cycles. In this study, the occurrence of 7 antibiotics and 3 antiretrovirals in source-separated urine, groundwater, wastewater and surface water of the peri-urban area of Chunga in Lusaka, Zambia, was studied. In groundwater, the pharmaceuticals were only sporadically present with 4 antibiotics and 1 antiretroviral detected. The concentration of the antibiotics ranged from below limit of quantification (<LOQ) to 880 ng/L, with sulfamethoxazole having the highest detection frequency of 42.3%. In the surface water, a comparatively high concentrati…
Application of Selected Methods of Black Box for Modelling the Settleability Process in Wastewater Treatment Plant
2017
Abstract The paper described how the results of measurements of inflow wastewater temperature in the chamber, a degree of external and internal recirculation in the biological-mechanical wastewater treatment plant (WWTP) in Cedzyna near Kielce, Poland, were used to make predictions of settleability of activated sludge. Three methods, namely: multivariate adaptive regression splines (MARS), random forests (RF) and modified random forests (RF + SOM) were employed to compute activated sludge settleability. The results of analysis indicate that modified random forests demonstrate the best predictive abilities.
Vision guided robotic inspection for parts in manufacturing and remanufacturing industry
2020
AbstractEnvironmental and commercial drivers are leading to a circular economy, where systems and components are routinely recycled or remanufactured. Unlike traditional manufacturing, where components typically have a high degree of tolerance, components in the remanufacturing process may have seen decades of wear, resulting in a wider variation of geometries. This makes it difficult to translate existing automation techniques to perform Non-Destructive Testing (NDT) for such components autonomously. The challenge of performing automated inspections, with off-line tool-paths developed from Computer Aided Design (CAD) models, typically arises from the fact that those paths do not have the r…
Predictive pumping based on sensor data and weather forecast
2019
In energy production, peat extraction has a significant role in Finland. However, protection of nature has become more and more important globally. How do we solve this conflict of interests respecting both views? In peat production, one important phase is to drain peat bog so that peat production becomes available. This means that we have control over how we can lead water away from peat bog to nature without water contamination with solid and other harmful substances. In this paper we describe a novel method how fouling of water bodies from peat bog can be controlled more efficiently by using weather forecast to predict rainfall and thus, minimize the effluents to nature. peerReviewed