Societal and economic aspects of a novel circular system for the valorisation of desalination brine and waste heat from a power plant

Direct disposal of concentrate brines produced in industrial plants can have a relevant impact to environmental systems. For this reason, brine treatment and valorisation could help to avoid disposal and produce marketable salts, thus representing a possible economic benefit. With this aim, a novel process, where advanced separation technologies are combined with waste heat recovery, is proposed within the EU-funded WATER MINING project. The Case Study presented in this work concerns the power plant in Lampedusa island, where waste heat and desalination brine are available to implement the process via a pilot plant to be installed for alternative thermal treatment of the brine. The aim is to achieve energy and water valorisation and producing high-quality salts (NaCl, Na2SO4, Mg(OH)2) and chemicals (HCl and NaOH). Beside the technological aspects, the novel process’ impacts to society, market and policy were investigated through a Value Sensitive Design approach (VSD) (Palmeros Parada et al., 2018). VSD is a design approach to proactively accommodate stakeholder values during the design of technologies (Friedman, 2017). For this, quantitative and qualitative data was collected from a review of the literature, and through interviews with four different type of stakeholders: (a) innovative technology suppliers (ResourSEAs), (b) local salt supplier (SoSALT); (c) innovation ecosystem representatives (ARCA); and (d) desalination user (SOFIP). From these data, societal values and tensions around the development and implementation of the innovative technologies, as well as both market and policy barriers and enablers have been identified. Stakeholders have been invited to participate in what we call a Community of Practice (CoP). Through the CoP, stakeholders have discussed the identified values, tensions, barriers, and opportunities for implementing the seawater desalination and brine treatment processes. In particular, societal concerns around impacts on water and energy use, especially considering the scarcity of these resources in the island, were analysed. The aim was to derive recommendations for the development of the technologies and their implementation. Overall, stakeholders have participated with enthusiasm to this experience by bringing their vast amount of practitioners’ knowledge and market insights that were explored, indispensable for setting a discussion on the market systems for circularly produced wastewater products.