Co-production of urea using melamine and CO2 stripping in urea production plants
Thread Content
I would like to ask fellow sailors: Does anyone know of any examples of plants where melamine processes are combined with CO2 stripping methods for producing urea? I have some questions regarding this!
Dear friends upstairs, there are many examples of the co-production of triamines and urea. After the integration of the processes, operating and managing the urea production unit becomes difficult, and consumption increases. Both the NH3 and CO2 processes have a significant impact on urea production following this integration; the specific issues will be discussed together.
Question to TUOHZHE Haiyou: 1. In examples of co-producing urea using the CO2 stripping method, is NH3 and CO2 from the triamine off-gases returned to the high-pressure section as methammonium solution through high-efficiency washing, or as a gas under pressure? 2. Is it necessary to replace the trays in the synthesis tower to improve the conversion rate? 3. Could you tell me which specific manufacturers the instances are from? My email address is ymtuegj12@163.com. Thank you for the advice!
Our factory has a triammonium methanamine treatment system; after methanamine is decomposed, the gas phase proceeds to the second-stage decomposition process, while the liquid phase goes to the second-stage recovery process
Dear colleague upstairs, \"After methamine is decomposed, the gas phase enters the second-stage decomposition process, while the liquid phase goes into the second-stage recovery process.\" The gas from the second-stage decomposition also needs to be mixed with water to form ammonium methoxide solution, which is then sent back to the high-pressure section; the water-to-carbon ratio in this case is much higher than the designed value.
Triamine exhaust gas is absorbed using dilute ammonia water; following medium-pressure separation, the gas phase is absorbed and cooled in a medium-pressure system before being returned to the high-pressure stage in the form of methylamine liquid
This post was last edited by bpf3860743 on 2019-1-8 at 15:34. In China, the low-pressure process for producing melamine through CO2 stripping of urea is currently utilized only by Xinjiang Jinjiang Chemical Industry. In this system, two sets of CO2 stripping units are used to recover amine waste gases; however, the steam consumption of this setup is high, and the distribution controls in the stripping towers get clogged frequently, requiring cleaning every six months on average. Additionally, a new medium-pressure system is needed, as otherwise the water-to-carbon ratio becomes too extreme, making it impossible to operate the high-pressure system