| 摘要 |
PROBLEM TO BE SOLVED: To reduce purge quantity and energy cost and to improve productivity by providing a jacket type reactor having vertical pipes, in which a catalyst is packed, and supplying a synthetic loop purge gas containing nitrogen and hydrogen to additionally produce. SOLUTION: A platinum group catalyst such as ruthenium using graphite as a carrier is packed into the reactor 16 and the jacket side thereof is kept isothermal by water for boiling, which is circulated through a pipe 20. The reactor has heat transfer surface area enough to keep the gas in the pipes at 315-435 deg.C under the pressure of 60-210 bar. The ammonia content in the supplied purge gas stream 12 and the produced gas stream 28 are respectively controlled to <=3 mol% and 15-40 mol%. The remaining purge gas after condensed ammonia is separated by a separator 34 is fed to a hydrogen recovering device 38 to separate and remove hydrogen 44, argon 46, fuel gas 48 and ammonia and the remaining nitrogen stream 52 is circulated to the reactor 16 while controlling the ratio H/N to <=2.2. A plant is improved by installing one pass direct type ammonia convertor for the purge gas from 2 lines. |
