For acid pickling heat treated mild steel and steel products, up to the middle of the last century, sulfuric acid was primarily in use, which has been replaced stepwise by hydrochloric acid since the sixties. During this time, the pickling of high alloyed steel with hydrofluoric acid or mixtures for hydrofluoric acid together with nitric acid has also been applied on industrial scale. The technologies used by several plant contractors hereby show considerable differences in their engineering.The study provides a survey of the progress in the state of art of regeneration tech- nology as well as the use of different pickling media in the form of a review on existing technologies as well as im- provements done within the recent years in the area. For acid pickling heat treated mild steel and steel products, up to the middle of the last century, sulfuric acid was primarily in use, which has been replaced stepwise by hydrochloric acid since the sixties. During this time, the pickling of high alloyed steel with hydrofluoric acid or mixtures for hydrofluoric acid together with nitric acid has also been applied on industrial scale. The technologies used by several plant contractors hereby show considerable differences in their engineering. The study provides a survey of the progress in the state of art of regeneration tech - nology as well as the use of different pickling media in the form of a review on existing technologies as well as im- provements done within the recent years in the area.