VDI 4635 Blatt 3.5:2026-05 - Draft

Conventional ammonia production is essential for the chemical industry and the manufacture of fertilizers. Without the fixation of nitrogen from the air in the form of ammonia and the resulting fertilizers, a large part of the world’s population could no longer be supplied with food. At the same time, conventional ammonia production is responsible for 1,5 % of global CO2 emissions.These emissions can be drastically reduced if the hydrogen required for the process is obtained from renewable sources, such as electrolysis using renewable electricity. Since the conventional process is a highly integrated procedure and not designed for flexible operation, the production of ammonia must be rethought in the context of power-to-X processes. This standard describes the differences to the conventional Haber-Bosch process and addresses the requirements arising from the PtX context.Future "green" ammonia synthesis processes can completely dispense with methane as an intermediate and convert hydrogen and nitrogen directly into ammonia. The synthesis of ammonia and, in particular, of downstream products such as nitrogen fertilizers can be carried out using biological and agricultural processes. Electrochemical synthesis of ammonia is also conceivable.

27.075, 27.190, 65.080