Ann: Green Iron grade concentrates produced using saline water, page-46

I was replying to the part where you said it seemed uneconomic. Perhaps reread what you wrote.
Regarding the green steel part, the plan is to produce HBR or some form of high purity iron, not steel.

Fe2O3 + 3H2 => 2Fe + 3H2O
Theres your stoichiometry for the reaction.

The customer who buys the iron feedstock can then add whatever additives they want to make various grades of steel at their pleasure.
Again, it's an exercise in environmentalism rather than economics, until the point that the tariffs/taxes etc become non competitive for the alternatives.