This document describes the research activities carried out for identifying industrial processes where membrane modules for high temperatrure oxygen separation can be integrated, with the aim of improving processes in terms of energy consumption and costs.

The analysis of industrial processes aims at identifying applications of interest for oxygen separation membranes, in order to demonstrate their effective competitiveness compared to conventional O₂ production technologies and promote their applicability in the industrial sector, as well as identifying the operating conditions to which the developed materials must be exposed.

In previous research works, the possibility of efficiently integrating oxygen separation membranes in industrial processes such as the production of glass and ceramics was investigated and confirmed, as well as the consequent advantages in terms of energy and costs. This work presents the first analyses conducted in the steel industry. The steel production process has been identified as suitable for the application of O₂ membrane separation technology, as it is a very energy-intensive process that operates at very high temperatures, allows for heat to be recovered and uses important amounts of oxygen. In addition, steel production is widespread throughout the world and plays a fundamental role at both an industrial and economic level.

In 2019, Italy reached a crude steel production of around 23 million tons, thus contributing to around 15% of European production and being second only to Germany. The main steel production processes are the integral cycle (based on the blast furnace process) and the electric cycle, but there also alternative processes such as direct reduction.

Due to the complexity of the processes and the numerous phases necessary to transform the raw materials into the finished product, a careful analysis was conducted aimed at identifying the processes whose energy sources can be used for heating the ceramic membranes, with special attention to the technical feasibility of heat recovery, process continuity/discontinuity and the possible presence of pollutants. In particular, the processes of the blast furnace, the oxygen converter and the electric furnace were analysed.

The study highlighted that heat sources that can potentially be used to heat a membrane module are available in steel production processes, but the impact of their use on the rest of the process is still to be assessed.