INSTALLATION AND PROCESS FOR THE PREPARATION OF HYDROGEN CYANIDE

摘要

Present invention relates to a process and an installation (100) for the preparation of hydrogen cyanide by the Andrussow process, and more precisely for improving the conditions of mixing the reactant gases before feeding the Andrussow type reactor (60), in order to improve safety, to avoid any risk of explosion and to produce HCN in safe and efficient manner. The installation is configured in such a manner that oxygen is pre-mixed with air with a ratio comprised between 20.95% and 32.5% by volume, preferably between 25% and 30.5% by volume; methane containing gas and ammonia are simultaneously added in the pre-mixture of oxygen-enriched air in such a manner that the volumic ratio of methane to ammonia is comprised between 1.35 and 1.02 depending on the content of oxygen into air; said obtained reactant gases mixture having a temperature comprised between 80° C. and 120° C., preferably between 95° C. and 115° C. for feeding the Andrussow type reactor (60).

主权项

1. An installation (100) for the preparation of hydrogen cyanide HCN, said installation comprising:
A) an Andrussow type reactor (60), in which is introduced a reactant gases mixture of methane-containing gas, ammonia and oxygen-enriched air, said mixture reacting inside said reactor (60) over a catalyst to produce HCN, B) upstream of said Andrussow type reactor (60) according to the direction of gas flow, gas feeding pipes (P1 to P4) for feeding the installation with each reactant gas, a first unit (U1) for pre-mixing oxygen with air before adding methane-containing gas and ammonia into the obtained pre-mixture of oxygen-enriched air, wherein said first unit (U1) comprises at least one oxygen online controller so as to control the ratio of oxygen into air, said ratio of oxygen to air comprising between 20.95% and 32.5% in volume of oxygen; C) a second unit (U2) for adding simultaneously methane-containing gas and ammonia into the oxygen-enriched air, with a volumic ratio of methane to ammonia, being between 1.35 and 1.02 depending on the proportion of oxygen into the oxygen-enriched air; and D) at least one heat exchanger for heating at least one of the reactant gases, in order to have a temperature of said reactant gases mixture feeding said Andrussow type reactor (60) comprised between 80° C. and 120° C.