Process for urea production and plant
US7220882B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 17, 2006 |
| Grant date | May 22, 2007 |
| Priority date | — |
| Expiry date | Apr 17, 2026 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J2219/0011
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
In a process for urea production of the type comprising the reaction between ammonia and carbon dioxide in a high-pressure reactor followed by an autothermal stripping of the resulting reaction mixture so as to obtain a gaseous flow comprising ammonia and carbon dioxide and a liquid flow comprising urea and residual carbamate in aqueous solution and by a stripping of said gaseous flow in units operating at medium pressure, a gaseous flow coming from said units operating at medium pressure and comprising ammonia and carbon dioxide is partially condensed in a condenser to give a mixed liquid/gaseous flow. The uncondensed gases comprising ammonia and carbon dioxide are separated from the liquid phase in a separator and subjected to washing in a packed portion of a column in countercurrent with a flow of a carbonate solution obtaining a gaseous flow essentially consisting of ammonia and a liquid flow comprising a carbamate solution in which the carbon dioxide contained in said uncondensed gases has been absorbed.This process allows an effective recovery of ammonia without carbon dioxide for the recycling to the synthesis reactor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.