The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 01, 1991
Filed:
Oct. 05, 1988
Alwyn Pinto, Middlesbrough, GB;
Imperial Chemical Industries PLC, London, GB;
Abstract
Ammonia synthesis gas is prepared by primary and secondary reforming followed by shift and carbon oxides removal. So that the process can use naphtha and methane, e.g. natural gas, as alternative feedstocks, at least the initial part of the primary reforming catalyst is alkalized. When using a methane feedstock, the primary reformer heating and outlet temperature are reduced compared to when using naphtha, and the amount of air fed to the secondary reformer is increased, so that, after shift, the hydrogen to nitrogen molar ratio of the gas stream is lower and is such that the gas contains an excess of nitrogen. This excess of nitrogen is subsequently removed, e.g. from the ammonia synthesis loop by a cryogenic hydrogen-recovery unit treating a loop purge stream and recovering hydrogen for recycle to the loop.