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Which primer to go over semi preped surface with rust residue

My company is involved with oil terminals along the east coast. From steel tanks to pipeline manifolds, there is rusted metal. Same goes for the buildings. My concern is stopping existing rust that is decades old. The area is too large to get all the rust off. Crews will only get what is easy to blast off. Don't expect spotless prep for an area this large. Eventually I want a Polyester Poly Urethane (LPU) paint for the top coat, or at least an Acrylic Poly Urethane, not a solvent based paint. There seems to be conflict with using a acid wash primer with a epoxy/Zinc. I am thinking to go Acid Wash Primer first, Epoxy only as a second coat and Polyester Poly Urethane for the top coat. I am under the impression that the epoxy will bond better to the acid wash. Looking for suggestions since the scale of this job is so large. Each tank holds one million gallons, there is more than one tank.

Blair Benson
tankage/ oil terminals - New Canaan, Connecticut, USA
2004

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2004

Dear Mr Benson,

I'm not an expert so don't depend on this advice, but I would advise a kind of Iron phosphate coating that could be brushed or sprayed on before any kind of painting. The red rust, should get to a dark grey-black phosphate, before you use your marine chloride resisting paints.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India