Keywords: Fertilizer materials, Fertilizer plants, Sulfuric acid, Phosphoric acid, Nitric acid, Ammonia, Urea, NPK.

Dramatic changes in process technology have taken place over the last few years even in the extremely conservative fertilizer industry. Examples are the introduction of hemihydrate processes to produce phosphoric acid, the application of the pipe reactor in granulating systems or optimisation of the energy balance in sulfuric acid plants. These developments were either made possible by the use of new materials or called for the development of new materials. There are examples for both development trends.

Alloyed steels and plastics are applied specifically at critical points in fertilizer plants. Equipment items and pumps which, even a few years ago, were considered to be expendable parts calling for replacement at regular short intervals, have almost all disappeared. Nevertheless, much remains to be done and we are pleased that we as plant engineers are in a position to assist our clients in solving all the remaining problems.

The paper discusses the materials used for a range of acid and fertilizer plants.

P Lüdtke and W Schalk, Lurgi Chemie-Metallurgie-Industriebau, Frankfurt-am-Main, Germany.

28 pages, 15 figures, 2 tables, 4 refs.