Issues with reversing the operation of the urea plant
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Is it appropriate to operate the urea plant in reverse mode, testing only the evaporation and granulation process, and then waiting until the right time comes (which may take several months) before starting up the entire system?
This post was last edited by htcfkq on 2010-9-29 16:13. Reverse driving? It’s a test drive, right? It’s not possible for a urea plant to operate a certain process system independently, right?
It should be feasible to test the evaporation system first, but at least the steam system and cooling water system should be tested first.
The steam system and water system are both ready; we will only test the evaporation system by dissolving urea in the urine tank for a practical trial run. My main concern is whether the evaporation equipment will corrode if it isn’t used for several months (even if it is cleaned thoroughly after the trial run) Is it necessary to try this way? Can’t using water flow to activate the entire system?
It’s just a trial run; production of urea will stop once it begins, and then waiting will be required until the preceding processes are ready for operation before a full-system trial run can be carried out. During this time, a long winter lies ahead. I don’t think it’s necessary to do this; what does it prove even if the evaporation system works successfully? The urea production process is already a highly mature technology; as long as the preceding processes are in place, there are no major issues with starting up urea production.
It’s understandable to conduct a physical test using urea for the evaporation section; however, it’s a tedious and labor-intensive process. Moreover, ammonia/urine is present everywhere, and it’s difficult to deal with them – can they be discharged? In fact, it’s sufficient to carry out a water test run and verify that vacuum pumping works properly. After that, wait for the next opportunity to add materials – there’s no problem as long as everything is cleaned up properly. Discharging substances carelessly would harm the environment.
There is absolutely no need for a physical test run for the evaporation section; wet vacuum pumping and dry vacuum pumping will suffice!
Reply to 1# Leng Xueyu Er11: I conducted only one granulation experiment. I used 100 tons of bagged urea to prepare a urea solution with a concentration of around 70%, and then I carried out evaporation and concentration followed by granulation. It’s quite troublesome.
Can we first conduct a joint test run of the cold and hot water systems in the evaporation system? Using urea is too risky in terms of safety and environmental impact.
We have just completed the evaporation process and achieved a successful first run, but we can’t deal with the ammonia tank issue. I’m practicing by carrying out desorption and hydrolysis on the dilute ammonia solution in the ammonia tank right now!
I don’t think it’s necessary to carry out physical granulation of urea; it’s sufficient if dry vacuuming and wet vacuuming can meet the required standards.