Coal-mine effluent treatment has the potential to both reduce the environmental impact of the effluent and provide economic opportunities by recovering valuable minerals and clean water. In this study, we modeled a novel treatment process, which includes nanofiltration (NF), two-step crystallization, reverse osmosis (RO), electrodialysis (ED), multi-effect distillation (MED), and a NaCl crystallizer, and performed a techno-economic analysis of its full-scale implementation, using a circular economy approach. We estimated the thermal and electrical energy consumption to be 745.5 kWhth/tonNaCland 565.1 kWhel/tonNaCl(or 13.6 kWhthand 10.3 kWhelper m3of feed effluent), respectively. The levelized cost of the NaCl salt that accounts for the revenue from the plant's co-products (Mg(OH)2, CaSO4and, pure water) was estimated to be 203 USD/tonNaCl. The economic viability of the treatment chain can be improved by using renewable electricity sources, reducing the total expenditure on NF and RO, and integrating alternate technologies into the treatment plant@en

The European Union's Environmental Technology Verification (ETV) program aims to foster innovative environmental technologies to reach the market and reassure potential users. This paper presents an investigation of using ETV for three technologies, being developed within the EU Zero Brine research and innovation project. The technologies were designed to recover high quality water, salts and minerals from brine solutions. The technologies in focus are the forward feed MED evaporator, the Multi Feed - Plug Flow Reactor Crystalliser and Eutectic Freeze Crystallization. The study sought to understand the challenges of the ETV process, the readiness and eligibility of technologies, and possible preparations within the project lifetime. Challenges identified included: understanding what sufficient market readiness is, and achieving this within the duration of a project (also linked to funding allocation for the ETV process); and developing suitable performance claims, supported with sufficient levels of test data. A simple framework is presented to aid the integration of ETV into the development process. It promotes the use of life cycle assessment to understand the environmental added value of the technology and aid the development of performance claims.

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Technological developments are opening new avenues to facilitate the circular economy through resource recovery from industrial wastewater. This paper presents the use of Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) in the development of technology solutions for the treatment of brine wastewater and recovery of by-products. Four industrial case studies are assessed that apply different innovative technology configurations, to treat the brines and recover the water, salts and mineral compounds. The assessment focusses on identifying hotspots and potential design improvements for the four case studies. In addition, the development of a unified approach for prospective LCA and LCC is illustrated to promote robustness and consistency in the analysis of the four systems. The analysis reveals that the impact and cost of treatment is highly dependent on the wastewater composition. Critically, whether the recovery of compounds and deionised water can counteract the impact and cost of the treatment systems. The early analysis suggests that this is possible for two of the cases studies. Estimates of the GHG emissions for the initial system analysis, range from 10 to 17 kg CO₂e/m³, whilst costs range from €10/m³ to €25/m³. However, both are expected to decrease at full scale and are sensitive to costs of energy, chemicals and revenue from recovered by-products. The LCA's highlight chemical and energy consumption as critical hotspots. Design considerations therefore focus on the reduction of chemicals, reuse or switching to lower impact chemicals, and maximising by-product recovery, and using renewable energy.

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Environmental pollution, resource scarcity, and freshwater shortage are critical world challenges facing humanity. Process industry produces large amounts of brine, a waste water with a high salinity level and often critical raw materials. This study applies the social life cycle assessment (S-LCA) to quantify societal benefits and risks in developing brine treatment systems. S-LCA is implemented for hotspot and site-specific levels on four case studies of the Zero Brine project. Hotspot analysis focused on the major commodities. Social Hotspot Database was used as source for data and endpoint indicators. In addition, site-specific analysis regarded the social performance of the case studies companies; interviews and questionnaires were performed with representatives of the four case studies. The collected data were converted to scores with subcategory assessment method and performance reference points. The results show that for all case studies “Labor rights and decent work” and “Health and safety” indicators result in the largest impacts due to imports of commodities from developing countries. Site-specific results show that the overall social sustainability performance of the case study companies is at a good level. The only potential areas for improvement are the “Occupational accidents” and “Contribution to the local community”. The former are minimally higher for silica plant and higher for coal mine in relation to these sectors average accidents rates. Furthermore, the coal mine company can contribute more to the local community and reduce conflicts concerning environmental impacts at the city level. Common identified hotspots among the case studies are: China, India and Congo. Reducing imports from these countries will significantly improve the societal performance of the brine systems.

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