Search results for "Economy"

Combining Membrane and Zero Brine Technologies in Waste Acid Treatment for a Circular Economy in the Hot-Dip Galvanizing Industry: A Life Cycle Persp…

2023

AbstractAn innovative approach of combining membrane and zero brine technologies for a joint treatment of industrial liquid waste is investigated regarding its environmental impacts compared to the existing liquid waste treatment. The object of investigation is the generation of waste acid solution by a hot dip galvanizing plant in Sicily, Italy. The waste acid solution contains hydrochloric acid, iron and zinc, which makes it a hazardous waste according to EU classifications. Environmental impacts are studied for two scenarios in the Tecnozinco hot-dip galvanizing plant in Sicily, Italy: (i) the current process of pickling with linear disposal of waste acid and (ii) the pickling combined w…

Valorization of seawater desalination brines through the integration of Eutectic Freeze Crystallization and Electrodialysis with Bipolar Membranes in…

2021

European policy encourages the adoption of sustainable systems that promote the efficient use and recovery of resources. Accordingly, this study proposes integrating two innovative technologies, including Eutectic Freeze Crystallization (EFC) and Electrodialysis with Bipolar Membranes (EDBM), for treating seawater desalination brines. Two experimental campaigns were conducted to assess the viability of this novel treatment chain. Using two lab-test rig units, the effect of various operating conditions on the outputs and general performance of both EFC and EDBM was evaluated. Firstly, results showed that EFC could manage seawater brines to (i) obtain pure sodium sulphate, and fresh water in …

Combined membrane and thermal desalination processes for the treatment of ion exchange resins spent brine

2019

Abstract The disposal of industrial wastewater effluents represents a critical environmental issue. This work focuses on the treatment of the spent brine produced by the regeneration of ion exchange resins employed for water softening. For the first time, a comprehensive techno-economic assessment and an analysis of the energy requirements of the treatment chain are carried out, via the simulation of ad hoc implemented models. The chain is composed of nanofiltration, double-stage crystallization and multi-effect distillation. The valuable product is the brine produced by the multi-effect distillation, which can be re-used for the regeneration. Therefore, the treatment chain’s economic feasi…

Towards the implementation of circular economy in the water softening industry: A technical, economic and environmental analysis

2020

Abstract To reduce the environmental impact of the industrial sectors, circular strategies should be implemented to purify the effluents and recover raw materials. In this context, a novel integrated methodological approach is proposed to identify the most suitable strategy to improve the sustainability of the water softening industry via the treatment and recycling of the produced wastewater. Different concentration technologies and energy supply systems are compared to find economically feasible and environmentally friendly treatment systems. The investigated chains present the same pre-treatment step (nanofiltration and crystallization) and different concentration technologies: Multi-Eff…

Techno-economic assessment of multi-effect distillation process for the treatment and recycling of ion exchange resin spent brines

2019

Abstract A treatment chain including nanofiltration, crystallization and multi-effect distillation (MED) is for the first time proposed for the treatment of an effluent produced during the regeneration of Ion Exchange resins employed for water softening. The goal is to recover the minerals and to restore the regenerant solution to be reused in the next regeneration cycle. MED is the most crucial unit of the treatment chain from an economic point of view. A techno-economic analysis on the MED unit was performed and a novel performance indicator, named Levelized Brine Cost, was introduced as a measure of the economic feasibility of the process. Different scenarios were analysed, assuming diff…

An integrated approach for the HCl and metals recovery from waste pickling solutions: pilot plant and design operations

2021

Abstract Continuous regeneration of industrial pickling solutions and recovery of valuable materials are implemented in a pilot-scale plant including diffusion dialysis (DD), where HCl is recovered, membrane distillation (MD), where HCl is concentrated, and reactive precipitation (CSTR), where metal ions are recovered in different forms. The integration of the three processes allows to minimize waste streams generation and to accomplish a closed-loop process, thus increasing the environmental sustainability and economic impact of the galvanizing industry. Process reliability was proved through the operation of a demonstrator in the real industrial environment of the Tecnozinco SrL hot-dip g…

Effective magnesium recovery via seawater brines mining

In the last couple of decades, a rising interest has been focused on the research of novel and unconventional sources for mining minerals, such as industrial waste brines. As an example, brines are produced by desalination plants and discharged directly, or after being treated, into receiving water bodies possibly causing environmental concerns and renouncing the possibility to recover minerals [1,2]. Within this framework, the Water Mining WU-H2020 project aims at implementing an advanced Zero Liquid Discharge (ZLD) demo systems for the extraction of minerals and valuables products from industrial waste brines through a circular approach. The ZLD demo plant consists of: (i) Nano Filtration…

Electrodialysis with Bipolar Membranes for the Sustainable Production of Chemicals from Seawater Brines at Pilot Plant Scale

2023

Environmental concerns regarding the disposal of seawater reverse osmosis brines require the development of new valorization strategies. Electrodialysis with bipolar membrane (EDBM) technology enables the production of acid and base from a salty waste stream. In this study, an EDBM pilot plant with a membrane area of 19.2 m2 was tested. This total membrane area results much larger (i.e., more than 16 times larger) than those reported in the literature so far for the production of HCl and NaOH aqueous solutions, starting from NaCl brines. The pilot unit was tested both in continuous and discontinuous operation modes, at different current densities (200-500 A m-2). Particularly, three differe…

Techno-economic analysis of a novel hybrid system for the valorisation of SWRO brines in a minor Sicilian island

2021

In small remote islands, freshwater scarcity is an issue to which several viable solutions have already been found employing constantly evolving desalination technologies. The several RO plants in the Canary and minor Sicilian Islands are just an example . However, the beneficial application of seawater desalination is accompanied by a problematic matter: the production of high salinity brines. Not only do they compromise the aquatic ecosystem but their treatment in order to respect environmental regulations is costly too. Worth noting how these so-called “wastewater streams” present a high concentration of valuable raw materials, such as magnesium and calcium or sodium chloride, that are e…

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…