Problems encountered in the conversion of the urea evaporation system from steam to water?
Thread Content
Our company has now decided to convert the urea evaporation system from a steam-based system to a water-based one, that is, to replace the steam jet pump with a hydraulic jet pump. To make the implementation process smoother and to facilitate future operations, we are seeking advice from those who have already completed this conversion: at what level of circulating water should it be sent to the carbon-ammonia liquid tank for decomposition?
Change your \"recirculated water\" to evaporated condensate – there’s no need to add external water. The evaporated condensate flows directly into the evaporated condensate tank, which is then added back to the system
When the urea content reaches 6%, or when the temperature is high and the vacuum level drops, it is sent for decomposition, with condensate being added simultaneously
We use a surface liquid as the spraying water; this liquid is continuously generated during production. The level in the storage tank is controlled by a regulating valve, and any excess liquid goes into the ammonia tank. The liquid is constantly in motion and being refreshed, so there is no issue with concentration. You can also adopt this type of discharge system, as it is energy-efficient and convenient to use.
Our company’s injectors originally used plain water, which caused severe scaling; now we use condensate, and the results are good.
Using water only once is not only wasteful but also prone to scaling; process condensate is generally a better choice.
We use two-stage evaporated condensate, and desalinated water is added to the storage tank as appropriate depending on the vacuum level for replacement.
A single-fluid or dual-fluid system can be used as the working fluid, which allows for recycling; thus, there is no need to worry about issues such as adding water or performing replacement. However, ammonium carbonate solution cannot be used directly, as during periods of system instability, or after maintenance or when the system is restarted after being shut down, the concentration of ammonium carbonate solution in the tank is high, which may affect the vacuum level.