Process for controlling the temperature during urea synthesis
US4154760A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1977 |
| Grant date | May 15, 1979 |
| Priority date | — |
| Expiry date | Jan 27, 1997 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C273/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A urea synthesis process for converting ammonia and carbon dioxide to urea is improved by providing an easy means of maintaining the urea synthesis zone in the process at a constant temperature. In the process the starting CO.sub.2 and up to and including 100 percent of the starting NH.sub.3 are reacted in a heat-recovery zone maintained at a urea synthesis pressure. Some of the heat of reaction is removed. The molar ratio of NH.sub.3 to CO.sub.2 which is fed into the heat-recovery zone is less than 4. The reaction mixture and the rest of the starting NH.sub.3 are fed into a urea synthesis zone maintained at urea synthesis pressure to produce urea. The improvement involves adjusting the amount of starting ammonia which is fed into the urea synthesis zone in response to any change in the temperature in the urea synthesis zone so that the urea synthesis zone is maintained at a substantially fixed temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.