Search results for "removal"
showing 6 items of 316 documents
A comparative study of different formulations of poultices for soluble salts removal from experimental plasters
2017
Soluble salts extractive capability of some commercial materials currently used in plaster restoration sector (ArbocelTM plus sepiolite; ArbocelTM, sepiolite and sand; Westox-Cocoon®) were tested in the present study, with the aim to evaluate their efficiency, their compatibility with the substrates as well as in terms of costs and duration of intervention. The three poultice products were first characterized in terms of porosimetric distribution. The desalination tests have been performed on samples of plaster specially formulated and made at the laboratory. Experimental specimens were then brought into contact with a solution of Na2SO4 0.3 M. The efficiency rating of these different types…
The use of industrial waste materials for the simultaneous removal of ammonium nitrogen and phosphate from the anaerobic digestion reject water
2020
The European Union’s circular economy strategy aims to increase the recycling and re-use of products and waste materials. According to the strategy, the use of industry waste materials and side flows is required to be more effective. In this research, a chemical precipitation method to simultaneously remove ammonium and phosphate from the reject water of anaerobic digestion plant using calcined paper mill sludge and fly ash as a precipitant, was tested. Paper mill sludge is a waste material formed in the paper-making process, and fly ash is another waste material formed in the power plant. Objective of this research was to test whether these industrial waste streams could be used as low cos…
Relationship between volume of submandibular salivary stones in vivo determined with cone-beam computer tomography and in vitro with micro-computer t…
2021
Background Successful removal of salivary stones depends on exact pretreatment information of the location, the size and shape of the stones. This study aimed to compare the volume of submandibular sialoliths determined by preoperative Cone-Beam Computer Tomography (CBCT) scans with the volume of the removed stones on micro-Computer Tomography (micro-CT) scans. Material and Methods In this study, using twenty-one submandibular sialoliths, the pretreatment volumes in-vivo measured on CBCT were compared to the volumes of removed stones determined by micro-CT scans. The volume measured on micro-CT scans served as the gold standard. Pre-operative CBCT’s and in-vitro micro-CT’s were converted in…
Particle balance and return loops for microplastics in a tertiary-level wastewater treatment plant.
2021
Highlights: Dewatering by centrifugation was a step that removed a high number of MPs from the sludge. Sludge retained especially the fibrous microplactics. Reject water transported microplastics inside a wastewater treatment plant. Disc filter-based tertiary treatment ensured removal of 99% of microplastics in wastewater. Microplastics (MPs) from households, stormwater, and various industries are transported to wastewater treatment plants (WWTPs), where a high proportion of them are captured before discharging their residuals to watersheds. Although recent studies have indicated that the removed MPs are mainly retained in wastewater sludge, sludge treatment processes have gained less atten…
Experimental investigation on the efficiency of zinc(II) recovery from waste streams by TBP liquid-liquid extraction
2016
In many industrial processes the presence of zinc in the wastewater may represent an obstacle to its high efficient regeneration. This is the case of the treatment of spent pickling solutions aiming the recovery of hydrochloric acid via pyrohydrolysis techniques. Hydrochloric spent pickling solutions from steel processing contain relevant amount of metals such as iron (Fe) and zinc (Zn) that may significantly affect recovery of hydrochloric acid (HCl) through pyrohydrolysis. In fact, although Fe may be recovered as ferric oxide (Fe2O3) and does not have a substantial effect on pyrohydrolysis process, zinc chloride (ZnCl2) evaporating can occlude nozzles and stick to the pyrohydrolysis react…
Recovering of zinc(II) from spent pickling solutions by liquid-liquid extraction
2015
Hydrochloric acid can be successfully recovered from spent pickling liquors with high efficiencies via pyrohydrolysis techniques. In the pickling solution feed, other metallic ions are typically present besides iron (mainly Fe2+) such as zinc(II). In order to avoid undesirable effects, zinc(II) has to be removed, because zinc chloride evaporates and sticks to the reactor walls, as well as it contaminates iron oxides product1. Moreover, zinc recovery is economically affordable because it allows the marketing of some products such as ZnCl2 and ZnSO4. In the present work, liquid-liquid extraction process has been selected to recover zinc(II) from pickling liquors, using suitable extractant age…