How to deal with the dilute ammonia water generated when the synthesis catalyst is reduced? , how many tons are there generally?
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How to deal with the dilute ammonia water generated when the synthesis catalyst is reduced? How many tons are there generally?
The initial concentration is extremely low and can be discharged directly if the requirements are not strict.； As the reduction proceeds, the ammonia concentration gradually increases. We collect it and send it to desulfurization or ammonia absorption for production. ； When the concentration reaches above 95%, put it directly into the storage tank. If ammonia is not absorbed and ammonia is not used for desulfurization, it can be recycled to the Chi Chi vent gas ammonia recovery system. The theoretical water output can be calculated based on the composition of the catalyst, and the formula is easy to find.
Most agree with the above. In order to judge the degree of reduction, the water output needs to be measured. Our method is to use a measuring bucket. To calculate the theoretical water output, two data are needed: Catalyst filling amount and catalyst ratio (ratio of iron oxide and ferric oxide, please consult the catalyst manufacturer for this data), simply put, knowing the amount of combined oxygen in the catalyst will also know the theoretical water output. There are many related posts in the dilute ammonia recycling forum, so I won’t repeat them here.
Ours are all discharged to the liquid ammonia storage tank. When we reduce, we usually produce one set. The theoretical water output of the reduction can be calculated according to any of the following formulas 1. G=W(Fe2+%×H2O/Fe+ Fe3+%×3H2O/Fe) 2. G=W(FeO%×1/4+ Fe2O3%×27/80) 3. G=18/55.86××(M+3/2)WG — Theoretical water output W - total weight of catalyst Fe2+% - mass fraction of ferrous iron Fe3+% - mass fraction of ferric iron H2O/Fe - ratio of molar mass of water to molar mass of iron FeO% - mass fraction of ferrous oxide Fe2O3% - mass fraction of ferric oxide T% - total iron (Fe2++ Fe3+) content M - iron ratio of catalyst Fe2+/Fe3+ This post was last written by snowdfr Edited at 2009-3-3 08:32 ]
Our company's reduced water is metered and then discharged into the ammonia water tank, where it is pumped through the urea hydrolysis system to recover ammonia or delivered separately. It should be noted that the catalyst powder should be separated and settled first. If it is not separated and sent to the treatment system, it will cause a series of phenomena such as blockage of the heat exchanger in the downstream process.
After measurement, it is sent directly to the ammonia water tank. The concentration is low at first, and then the concentration is high. It is mixed and sold according to the concentration. When the concentration is almost the same, just change it to the ammonia tank. There should be a measuring tool when the water is discharged. We have a special measuring tank, which is used when the temperature is restored. After the restoration is completed, just compare it with the theoretical water output.
We do not do any special measurement of the effluent during reduction. We just look at the water vapor concentration and temperature to judge the degree of reduction. When the ammonia concentration is low, it is sent to the gas station to increase the concentration and is used as commercial liquid ammonia or for personal use. When the concentration reaches above 90, it is sent to the storage tank.
We seldom analyze the water vapor concentration, use a scale to weigh it, analyze the ammonia content to calculate the water volume, discharge water once every hour when it is small, and every half hour when it is large, and indirectly estimate the water vapor concentration based on the water volume.