In melamine synthesis, urea is converted to melamine at approx. 400 °c and approx. 2 bar at a Si02 I Al203 catalyst in a synthesis line. As a by-product, ammonia and carbon dioxide are produced in stoichiometric quantities in the process gas.
Hydrogen cyanide as well as multinuclear condensation products of melamine and (partially) hydrolyzed melamine derivatives are also produced in small quantities as secondary components. After separating the melamine from the process gas, it is fed via catalytic decomposers to minimize the minor components. The process gas is then fed to the process gas separation plant in U 024. In addition, a partial flow in the process gas processing can be processed into ammonium nitrate solution and delivered to external factories such as the field fertilizer factory or the nitric acid factory. These plants are not part of the melamine factory, but the exhaust gas flow is generated and must be supplied.
Liquid ammonia (approx. 11 bar) from the gas separation plant is supplied to the external urea factory, fed into the plant network or fed back into the melamine synthesis. The C02-containing residual gases from the process gas processing plant U 028 and the process gas separation plant U 024 are emitted via the outlets