Search results for "Sewage sludge"
showing 10 items of 54 documents
Ekstrakcja fosforu z osadów ściekowych i popiołów ze spalania osadów - analiza problemu
2016
Fosfor jako pierwiastek niezbędny do produkcji rolniczej, w miarę wyczerpywania się zasobów fosforytów, staje się komponentem coraz bardziej deficytowym. Koniecznym wydaje się wdrożenie metod taniego i efektywnego odzysku tego pierwiastka z wszelkiego rodzaju odpadów. Szczególnie cennym źródłem fosforu są popioły z osadów ściekowych i same osady. Optymalizacja metod sekwencyjnej ekstrakcji fosforu zawartego w popiele z termicznego przekształcania osadów ściekowych i odwodnionych osadów pozwala na wybór efektywnej i nieskomplikowanej technologicznie możliwości odzysku fosforu, przy jednoczesnym zachowaniu niskiego obciążenia eluatu metalami ciężkimi, które są jedną z głównych przyczyn ograni…
Removal of bis(2-ethylhexyl) phthalate at a sewage treatment plant
2003
Bis(2-ethylhexyl) phthalate (DEHP) concentrations were measured at different stages in a full-scale sewage treatment plant (STP) and mass balances were calculated. The DEHP load to treatment process coming from the sewer system and the internal load comprising returned supernatants and filtrate from sludge treatment and excess secondary sludge were at the same level. The DEHP removal efficiency from the water phase at the STP was on average 94% of sewage DEHP, the main removal process being sorption to primary and secondary sludges. On average 29% of DEHP was calculated to be removed in the biological nitrifying-denitrifying activated sludge process, which was much less than expected from l…
Hydrothermal liquefaction of sewage sludge: towards the effects of transition metals in the presence of homogeneous hydrogen producers
2022
Waste carbonaceous matrices, such as sewage sludge (SS) seem to have a great potential, because they are namely costless matrices compared to the microalgae and hydrothermal liquefaction (HTL) can be considered an interesting route to dispose and valorize them [1-5]. However, SS are characterized by high amount of non-biogenic fractions, such as plastics, salts and metals. In particular SS contains a high amount of inorganics [5], such as Al, Ba, Ca, Cr, Cu, Fe, Ni, K, Mg, Mn, Na, P, S, Ti, Zn, Si which are distributed in the products at the end of the reaction. The presence of heavy metals represent a big challenge for the implementation of HTL on the industrial scale as they can affect pr…
Optimal Solutions for the Use of Sewage Sludge on Agricultural Lands
2021
The use of sewage sludge in agriculture decreases the pressure on landfills. In Romania, massive investments have been made in wastewater treatment stations, which have resulted in the accumulation of important quantities of sewage sludge. The presence of these sewage sludges coincides with large areas of degraded agricultural land. The aim of the present article is to identify the best technological combinations meant to solve these problems simultaneously. Adapting the quality and parameters of the sludge to the specificity of the land solves the possible compatibility problems, thus reducing the impact on the environment. The physico-chemical characteristics of the fermented sludge were …
Pharmaceuticals in processing of municipal sewage sludge studied by grab and passive sampling
2018
Abstract Concentrations of pharmaceuticals, consisting of four anti-inflammatory and one antiepileptic drug, were studied in the aqueous and solid phase of municipal sewage sludge, collected from a wastewater treatment plant (WWTP) in central Finland. The samples included untreated municipal sludge from the biological wastewater treatment, digested sludge and sludge before and after composting. First, samples were taken as grab samples to study the bioavailable part in aqueous phase but also the part in solid fraction. Later, the long-term concentrations were studied by passive sampling with styrene divinylbenzene-reverse phase sulfonated (SDB-RPS) disks. In the untreated solid sludge, the …
Initial pH Conditions Shape the Microbial Community Structure of Sewage Sludge in Batch Fermentations for the Improvement of Volatile Fatty Acid Prod…
2022
Conversion of wastewater treatment plants into biorefineries is a sustainable alternative for obtaining valuable compounds, thus reducing pollutants and costs and protecting the environment and human health. Under specific operating conditions, microbial fermentative products of sewage sludge are volatile fatty acids (VFA) that can be precursors of polyhydroxyalkanoate thermoplastic polyesters. The role of various operating parameters in VFA production has yet to be elucidated. This study aimed to correlate the levels of VFA yields with prokaryotic microbiota structures of sewage sludge in two sets of batch fermentations with an initial pH of 8 and 10. The sewage sludge used to inoculate th…
Mobilność wybranych metali ciężkich w komunalnych osadach ściekowych
2016
The research was aimed at determining the interaction of municipal sewage sludge with the environment in the aspect of its potential for land applications in agriculture, land reclamation and land adaptation to different uses. Sequential extraction of heavy metals according to Brümmer’s method was used in the study. A detailed interpretation of the data allowed to state that the highest content of copper was found in one of the most mobile bindings (fraction I). For other heavy metals only trace amounts were found in the bindings considered as the most mobile (fraction I-III) which proved less risk posed to the environment. The highest percentage share of heavy metals in the investigated sl…
Analysis of the Mobility of Heavy Metals in Sludge for the Sewage Treatment Plant in Daleszyce
2020
Osady ściekowe są produktem ubocznym procesów oczyszczania ścieków. Wykazują jednak wysokie właściwości nawo-zowe oraz glebotwórcze, jednak nie zawsze mogą być one wykorzystane w tym celu. Dwa główne kryteria ograniczające ich przyrodnicze wykorzystanie to zawartość metali ciężkich oraz jaj pasożytów. Osady ściekowe pobrane z oczyszczalni ścieków w Daleszycach zostały poddane analizie zawartości metali ciężkich. W tym celu wykonano analizę specjacyjną, pozwalającą podzielić całkowitą zawartość metali na cztery frakcje mobilności. Mobilność określa zdolność pierwiastka, lub któregoś z jego form, do przemieszczania się w środowisku. Badania wykonano, stosując czteroetapową procedurę BCR. Wyni…
Hydrothermal co-liquefaction of sewage sludge and formic acid
2019
The biocrude produced by non-catalytic hydrothermal liquefaction (HTL) has a too high heteroatom content to be used directly as a fuel [1-3]. Several studies found that different H2 initial pressures during HTL experiments were ineffective in improving the biocrude yield [4-6], nevertheless it was observed that higher initial pressures of H2 brought an improvement of the concentration of light compounds in the biocrude, decreasing the average molecular weight of biocrude oil. To date H2 is mainly generated from fossil sources and realization of a possible hydrogen economy from alternative sources presents many challenges. The use of a liquid hydrogen storage media could represent for the HT…
Optical Monitoring of Microplastics Filtrated from Wastewater Sludge and Suspended in Ethanol.
2021
The abundance of microplastics (MPs) in the atmosphere, on land, and especially in water bodies is well acknowledged. In this study, we establish an optical method based on three different techniques, namely, specular reflection to probe the medium, transmission spectroscopy measurements for the detection and identification, and a speckle pattern for monitoring the sedimentation of MPs filtrated from wastewater sludge and suspended in ethanol. We used first Raman measurements to estimate the presence and types of different MPs in wastewater sludge samples. We also used microscopy to identify the shapes of the main MPs. This allowed us to create a teaching set of samples to be characterized …