Search results for "SEPARATION"
showing 10 items of 865 documents
Diffusion dialysis for the treatment of H2SO4-CuSO4 solutions from electroplating plants: Ions membrane transport characterization and modelling
2021
Diffusion dialysis (DD) is proposed to separate and recover mineral acids and transition metals from electroplating industry process waters promoting a circular approach of resources recovery. In this work, a DD module with two anionic membranes (Fumasep FAD and Neosepta AFN) are used for the separation of H2SO4 from Cu2+ containing solutions. The membrane performances with sole H2SO4 solutions (0.2–2 M) and sole CuSO4 solutions (0.8–1.1 M Cu2+) and with mixtures of H2SO4 (0.6 M) and CuSO4 (0.2–1.1 M Cu2+) as feed are studied. H2SO4 recovery efficiency decreases as the concentration of acid increases. For H2SO4 solutions, the water drag flux from the retentate to the diffusate prevails agai…
A Novel Ionic Exchange Membrane Crystallizer to Recover Magnesium Hydroxide from Seawater and Industrial Brines
2020
A novel technology, the ion exchange membrane crystallizer (CrIEM), that combines reactive and membrane crystallization, was investigated in order to recover high purity magnesium hydroxide from multi-component artificial and natural solutions. In particular, in a CrIEM reactor, the presence of an anion exchange membrane (AEM), which separates two-compartment containing a saline solution and an alkaline solution, allows the passage of hydroxyl ions from the alkaline to the saline solution compartment, where crystallization of magnesium hydroxide occurs, yet avoiding a direct mixing between the solutions feeding the reactor. This enables the use of low-cost reactants (e.g., Ca(OH)2) without …
Economic Benefits of Waste Pickling Solution Valorization
2022
An integrated hybrid membrane process, composed of a diffusion dialysis (DD), a membrane distillation (MD) and a reactive precipitation unit (CSTR), is proposed as a promising solution for the valorization and onsite recycling of pickling waste streams. An economic analysis was performed aiming to demonstrate the feasibility of the developed process with a NPV of about EUR 40,000 and a DPBP of 4 years. The investment and operating costs, as well as the avoided costs and the benefits for the company operating the plant, were analyzed with an extensive cost tracking exercise and through face-to-face contact with manufacturers and sector leaders. A mathematical model was implemented using the …
Electrodialysis Applications in Wastewater Treatment for Environmental Protection and Resources Recovery: A Systematic Review on Progress and Perspec…
2020
This paper presents a comprehensive review of studies on electrodialysis (ED) applications in wastewater treatment, outlining the current status and the future prospect. ED is a membrane process of separation under the action of an electric field, where ions are selectively transported across ion-exchange membranes. ED of both conventional or unconventional fashion has been tested to treat several waste or spent aqueous solutions, including effluents from various industrial processes, municipal wastewater or salt water treatment plants, and animal farms. Properties such as selectivity, high separation efficiency, and chemical-free treatment make ED methods adequate for desalination and othe…
Energetic Valorisation of Saltworks Bitterns via Reverse Electrodialysis: A Laboratory Experimental Campaign
2023
Concentrated bitterns discharged from saltworks have extremely high salinity, often up to 300 g/L, thus their direct disposal not only has a harmful effect on the environment, but also generates a depletion of a potential resource of renewable energy. Here, reverse electrodialysis (RED), an emerging electrochemical membrane process, is proposed to capture and convert the salinity gradient power (SGP) intrinsically conveyed by these bitterns also aiming at the reduction of concentrated salty water disposal. A laboratory-scale RED unit has been adopted to study the SGP potential of such brines, testing ion exchange membranes from different suppliers and under different operating conditions. M…
Separation of Concerns and Role Implementation in the PASSI Design Process
2007
The use of design patterns proved successful in lowering the development time and number of errors when producing software with the object-oriented paradigm. In previous works we engaged the production of a tool for the reuse of patterns for multi-agent systems. Now we are fronting a new problem: automatic code generation for agents, designed with a specific methodology, with the support of design patterns and using an aspect oriented approach. In this work we present our preliminary experiences in the identification, description, production and use of aspects for multi agent systems and a tool for code production.
Desobediencia civil y participación política. Unas cuestiones abiertas para las democracias constitucionales (y la teoría del derecho)
2015
In this article I try to show some problems of the interpretation of civil disobedience as a practice that aims to maintain democratic principles against discriminative legal patterns or oligarchic forces. I will present two doctrines, the Rawlsian (followed by Habermas) and the one proposed recently by supporters of a radical constitutional change through the exercise of “constituent power”. The Rawlsian account a) offers a too stringent model of justification of this type of practice and b) does not recognize the plurality of subjects to which civil disobedience appeal. The supporters of radical constitutional change fall into a form of heterogony of ends. They reject liberal accounts of …
Principles, balancing, and the separation between law and morals: on neo-constitutionalism and its critics
2011
En el ensayo Constitucionalismo principialista y constitucionalismo garantista, Luigi Ferrajoli ofrece una oportuna clarificación teórica y conceptual sobre el así llamado neoconstitucionalismo. Por mi parte, en esta contribución intentaré desarrollar algunas observaciones sobre tres puntos acerca de los cuales me encuentro en relativo desacuerdo con el análisis de Ferrajoli: el tratamiento de la distinción entre reglas y principios, la interpretación de la práctica de la ponderación, y el problema de la separación entre Derecho y moral. Además, ofreceré un panorama de los significados del (neo)constitucionalismo, y, respecto a tal panorama, consideraré el modo en el cual Ferrajoli sitúa su…
Twins. Similarities, differences and individuality
2015
This study aims to investigate the self-differentiating perceptions and the separation-individuation’s process in emerging adulthood twins. A group of 40 Italian pairs of twins (21 couples dizygotic-DZ and 19 monozygotic-MZ) aged 20-30 years, were evaluated using the test of graphic projection Family Life Space (DSSVF) and thought a specific questionnaire ad hoc constructed for this research. The research hypothesis focus on Zazzo’s test of parallel testimony and provide to give empirical evidence about the capacity of MZ Twins to use more internal resources of the couple than DZ Twins, causing the split slowdown on identification. The data show that there are no difference between not bise…
First Study on Nihonium (Nh, Element 113) Chemistry at TASCA
2021
Frontiers in Chemistry 9, 753738 (2021). doi:10.3389/fchem.2021.753738