Discussion on the 5 New Urea Technologies Series, Part 3 (Medium-Pressure Carbon Doping)
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On January 31, 2009, jindin312 reported on the news that “for the first time in the world, 5 technologies were successfully applied in a urea project” (see the Chemical Industry News of January 16). This news is certainly very encouraging for the nitrogen fertilizer industry; if this \"world-leading high-tech technology\" proves to work successfully in actual production, it can be considered a major advancement in urea technology. Regarding these 5 technologies, I believe that most users working with urea are not very familiar with them. Therefore, I suggest that we discuss each of these technologies in detail, based on the information we have, so that we can all gain a deeper understanding of these 5 technologies and work together to improve our skills. This post focuses on the third technique: how to carry out “medium-pressure carbon addition”? Which device could it be installed in? What is its function? We welcome everyone to participate actively, with extra rewards for in-depth discussions. This post was last edited by lxq700918 on 2009-2-11 17:50.]
Regarding medium-pressure carbonation technology, it is estimated that, similar to the UTI technology, part of the CO2 is compressed and fed into the medium-pressure system, where it reacts with the gas produced by medium-pressure decomposition and dimethylamine from the low-pressure absorption system to form methylammonium. The heat generated by this reaction is used as a heat source for the decomposition and concentration of the urea solution coming out of the urea tower, before it is sent to the first absorption tower. In this way, the heat of condensation resulting from low-energy reactions can be recovered and utilized, thereby saving steam consumption. Please, experts, continue.
The carbon supplementation method using UTI is likely not being used in its entirety; it’s possible that CO2 is first added to the vapor from stage 2 before it enters the low-pressure recovery unit, and then dimethyl pump is used to add vapor from stage 1 in order to achieve carbon supplementation at medium pressure. Another location where carbon supplementation takes place is the hydrolysis system – the addition of substances there serves a stripping function, and the vapor at 160 degrees is directly introduced into stage 2, thereby serving as a heating element and also enabling carbon supplementation.
The “vapor from stages 1 and 2” mentioned on the 3rd floor probably refers to the decomposition vapor from stages 1 and 2, right? When it comes to flash vapor, it is easy to confuse it with the evaporation process. However, the several carbon-sequestration solutions mentioned by the original poster do make sense.
What the original poster is saying is that we actually studied these five technologies back in 2000; they’re not anything new. I used them in the urea system I designed in 2006. If you have any questions, feel free to contact me: handshake :victory:
Carbon supplementation can be considered for the stripping type single column
Is the medium-pressure carbon addition done as follows? A self-stripping single column with falling film heat exchange is employed, with CO2 being introduced from the lower part of the column to undergo countercurrent mass and heat transfer with urine, thereby reducing the steam consumption for the first stage of decomposition.
The vast majority of these additions are made to the first stage of the system, with the aim of increasing the CO2 content in the pre-distillation gas, enhancing the recovery of reaction heat in the first evaporation stage, and reducing steam consumption in that stage
What carbon sequestration, no carbon sequestration! What’s the essential difference in where to add it? ? ? In the so-called self-aerating fractional distillation column, how can it be compared with the carbon dioxide stripping method? How much more ammonia and steam can be saved? Are some of those so-called large devices that claim to save energy really that good? ? ? ? Can some unproven so-called processes truly bring benefits to businesses? :o :o :o Managing the existing production and making appropriate modifications – that’s the feasible approach! ! !
Perhaps trying different approaches and learning from others could bring good news to the industry; each method has its own advantages