1 research outputs found
Combining Membrane and Zero Brine Technologies in Waste Acid Treatment for a Circular Economy in the Hot‑Dip Galvanizing Industry: A Life Cycle Perspective
An 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 classifcations. 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 with in-situ treatment of the waste acid using a combination
of difusion dialysis (DD), membrane distillation (MD) and a precipitation reactor. Results are obtained via an attributional
life cycle assessment (LCA) approach focusing on the water footprint profle of the process. The linear disposal path creates
signifcant costs, environmental burdens and risks during the 1500 km transport of hazardous liquid waste. The combination
of DD and MD, complemented with a zero-brine precipitation reactor, closes internal material loops, could save local water
resources and reduces costs as well as environmental impacts. Reduction potentials of 70–80% regarding most LCA impact
categories can be expected for the application of the novel technology combination supporting the galvanizing pre-treatment
process under study. Therefore, the application of such technology on the way forward to a more circular economy is recommended from an environmental viewpoint, especially in process plants similar to the investigated one