Search results for "diffusion dialysi"
showing 4 items of 14 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…
Modeling and Design of Membrane Process Recovery of HCl and Metals from Pickling Solutions
2018
Abstract Hydrochloric acid pickling is one of the key steps in the hot-dip galvanizing process. It is a process widely used as a chemical pre-treatment method for cleaning, where metal surfaces with oxides are immersed into an acid solution. During the pickling process, the acid concentration decreases with time while the metal is accumulated. Thus, the efficiency of the pickling solution decreases and fresh solution must be used. Continuous regeneration of pickling solutions enhances pickling rate and process performance, but also minimises industrial wastewater disposal and chemicals consumption. The recovery and recycling process of valuable substances (e.g. acid and metals) can be accom…
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 …
Modeling and Design of Membrane Integrated Processes for HCl and Metals Recovery from Pickling Solutions
2018
Hydrochloric acid pickling is a common practice in steel manufacturing industry. During the process, acid is consumed to dissolve surface oxides and metals are accumulated in the solution. This fact leads to a process efficiency decrease. Continuous regeneration of pickling solutions enhances process rate and performance, but also minimises the highly expensive and environmentally risky wastewater disposal. The recovery of valuable substances (e.g. acid and metals) can be accomplished by coupling diffusion dialysis (DD) and membrane distillation (MD) technologies. In the present work, a steady state process simulator for the integrated process has been developed. The aim is to analyze and p…