Patent · US Expired

Process for combined production of ammonia and urea

US6696026B2 · kind B2 · utility

8Cited by
13References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 16, 2001
Grant dateFeb 24, 2004
Priority date
Expiry dateJan 16, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/582
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process for the combined production of ammonia and urea of the type comprising an ammonia synthesis reactor (2), a urea synthesis reactor (5) and a urea recovery section (21) stands out for the fact of submitting at least a part of a flow comprising carbamate in aqueous solution coming from the urea recovery section (21) to a partial decomposition treatment, to obtain a flow comprising ammonia and carbon dioxide in vapor phase and a flow comprising diluted carbamate in aqueous solution, which is fed together with a gas flow comprising hydrogen, nitrogen and carbon dioxide, preferably obtained by hydrocarbons steam reforming, and a flow comprising ammonia coming from the ammonia synthesis reactor (2) to a carbamate synthesis section (3), where ammonia and carbon dioxide are caused to react, to obtain a flow comprising carbamate in aqueous solution and a gas flow comprising hydrogen and nitrogen. The flow comprising carbamate in aqueous solution is then sent to the urea synthesis reactor (5), while the gas flow comprising hydrogen and nitrogen is sent to the ammonia synthesis reactor (2).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.