The current theory regarding ammonia synthesis is incorrect; I hope everyone will share their practical experience to help develop the correct theory

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This post was last edited by Cross-Era Demon on 2017-5-22 at 11:50. Recently, I have expressed some opinions on HaiChuan; they actually concern one issue, namely that the theories used to guide the production of ammonia over the past hundred years are actually incorrect. Synthetic ammonia is more about practice; theory has not truly solved the issue. My first post was: \"Question: Is there a mathematical formula to calculate the ammonia content in the effluent from the tower?\" 》It is as follows: In fact, to this day I have not seen any method for calculating the content in the gas exiting the tower in ammonia synthesis. There’s tons and tons of information regarding the equilibrium of hydrogen-nitrogen synthesis; in reality, ammonia plants have no use for it. What interests ammonia synthesis plants is the ammonia content at the exit of the tower and the net ammonia value, but there is no method for calculating the ammonia content at the exit of the tower. Did I say that? If there is a calculation method, I hope everyone can provide it. Advanced parameters include feed temperature, pressure, space velocity, hydrogen and nitrogen partial pressures, inert gas partial pressures, and ammonia partial pressure at the inlet to the tower. Add another coefficient—representing the structure of the synthesis tower and the properties of the catalyst. At the very least, it is necessary to figure out how to determine the ammonia content in the gas leaving the tower, once the air velocity, hydrogen and nitrogen partial pressures, inert gas partial pressures, and ammonia partial pressure entering the tower have been established. The presence of inert gases gives an approximate formula for the equilibrium in hydrogen-nitrogen synthesis; but is it the same proportion as the ammonia content in the gas leaving the tower? The content of ammonia entering the tower is generally only described qualitatively, and I suspect it is incorrect. It is true that a lower ammonia content in the gas entering the tower reduces the synthesis rate and the net amount of ammonia produced; however, the ammonia content in the gas exiting the tower should increase slightly! What exactly is their relationship? Thank you all for the discussion! Additionally, regarding the question \"When the inert gas content in the feed ammonia changes, how does the ammonia content in the output change?\", the details are as follows: the ammonia content in the feed is x1 and the inert gas content is z1, while the ammonia content in the output is y1. So, when the ammonia content entering the tower is x2 and the inert gas content is z2, what is the ammonia content y1 exiting the tower? All other conditions remain unchanged. I hope experts can provide corrections. Quantitative calculation is required; provide mathematical formulas so that it can be calculated. There will be no response, and no one will reply. Because in fact, none of the textbooks provide any guidance on how to solve this problem. A misconception that has long existed in articles and books on synthetic ammonia must be corrected. I said in > this: For example, a textbook states that in production, the hydrogen-to-nitrogen ratio of the gas circulating within the tower should be maintained between 2.5 and 2.9. Since the hydrogen-to-nitrogen ratio used in synthesis is 3:1, the hydrogen-to-nitrogen ratio of the fresh gas added should also be 3; otherwise, excess hydrogen or nitrogen will accumulate in the circulation system, leading to an imbalance in the hydrogen-to-nitrogen ratio of the circulating gas. ——This claim is wrong! When venting air, nitrogen usually makes up a little over one-third of hydrogen; in liquid ammonia, even less hydrogen is dissolved, with it being only slightly more abundant than nitrogen at best. Therefore, proportionally, the loss of nitrogen is always higher than that of hydrogen. Therefore, if the gas fed into the reactor—whether it’s fresh gas being added, or a mixture of recycled gas and fresh gas—is proportioned at a ratio of 3:1, then the amount of nitrogen inside the synthesis reactor will gradually decrease, while the hydrogen-to-nitrogen ratio will continue to increase. Even if the synthesis tower is determined from the start to produce at a 3:1 ratio, the dissolution of liquid ammonia will cause nitrogen to decrease much more rapidly than hydrogen, resulting in production at a hydrogen-to-nitrogen ratio of over 3, which is unfavorable for the production process. The hydrogen-to-nitrogen ratio of the fresh gas should be less than 3; the excess nitrogen supplied should be sufficient to compensate for the losses of nitrogen in the exhaust gases and through ammonia dissolution. But it’s not just this textbook; almost all documents state this, or with slight variations – some say that the fresh gas ratio must be 3:1, while others say that the combined ratio of fresh gas and recycled gas should be 3:1 – and all of these are incorrect. If this mistake did not have any consequences, then it should be the case that people control the process strictly based on practical experience: when there is too much nitrogen, hydrogen is added to regulate it, and when there is too much hydrogen, nitrogen is added to regulate it. They didn’t even bother to consider what the book said. The so-called “ammonia balance” is also a vague concept. There is more gas entering the tower than exiting it; how can simple subtraction be used? To measure the synthesis amount in the reactor, it should be the total volume of ammonia in the gas exiting the reactor, minus the total volume of ammonia in the gas entering the reactor; the proportion of this value in the gas exiting the reactor is slightly lower than what would result from a simple subtraction. Approximately, it can also be expressed in that way. Actually, this is still a minor error, but despite being copied for a hundred years, no one raised any objections! In the post titled “How does the synthesis system operate when there is an imbalance in the hydrogen-to-nitrogen ratio?”, I replied as follows: Chemical gas purification, published on 2010-11-29 at 16:32. I remember that during courses on gas production, teachers often said, “If there’s too much nitrogen, add hydrogen; if there’s too much hydrogen, add nitrogen.” Therefore, during actual production, there is no concern about maintaining a hydrogen-to-nitrogen ratio of 3:1; the idea that the so-called fresh gas or gas entering the tower must be at a 3:1 ratio is completely fabricated and unscientific. In fact, a hydrogen-to-nitrogen ratio slightly less than 3 is the normal condition. A long-standing misconception in articles and books on ammonia synthesis must be corrected. For example, one textbook states that in production, it is appropriate to maintain a hydrogen-to-nitrogen ratio of 2.5 to 2.9 for the gas circulating within the tower. Since the hydrogen-to-nitrogen ratio used in synthesis is 3:1, the hydrogen-to-nitrogen ratio of the fresh gas added should also be 3; otherwise, excess hydrogen or nitrogen will accumulate in the circulation system, leading to an imbalance in the hydrogen-to-nitrogen ratio of the circulating gas. ——This claim is wrong! When venting air, nitrogen usually makes up a little over one-third of hydrogen; in liquid ammonia, even less hydrogen is dissolved, with it being only slightly more abundant than nitrogen at best. Therefore, proportionally, the loss of nitrogen is always higher than that of hydrogen. Therefore, if the gas fed into the reactor—whether it’s fresh gas being added, or a mixture of recycled gas and fresh gas—is proportioned at a ratio of 3:1, then the amount of nitrogen inside the synthesis reactor will gradually decrease, while the hydrogen-to-nitrogen ratio will continue to increase. Even if the synthesis tower is determined from the start to produce at a 3:1 ratio, the dissolution of liquid ammonia will cause nitrogen to decrease much more rapidly than hydrogen, resulting in production at a hydrogen-to-nitrogen ratio of over 3, which is unfavorable for the production process. The hydrogen-to-nitrogen ratio of the fresh gas should be less than 3; the excess nitrogen supplied should be sufficient to compensate for the losses of nitrogen in the exhaust gases and through ammonia dissolution. But it’s not just this textbook; almost all documents state this, or with slight variations – some say that the fresh gas ratio must be 3:1, while others say that the combined ratio of fresh gas and recycled gas should be 3:1 – and all of these are incorrect. If this mistake did not have any consequences, then it should be the case that people control the process strictly based on practical experience: when there is too much nitrogen, hydrogen is added to regulate it, and when there is too much hydrogen, nitrogen is added to regulate it. They didn’t even bother to consider what the book said. Somehow? It’s clearly a fallacy, yet it persists for a hundred years without wavering. The so-called “ammonia balance” is also a vague concept. There is more gas entering the tower than exiting it; how can simple subtraction be used? To measure the synthesis amount in the reactor, it should be the total volume of ammonia in the gas exiting the reactor, minus the total volume of ammonia in the gas entering the reactor; the proportion of this value in the gas exiting the reactor is slightly lower than what would result from a simple subtraction. It can be used approximately as well. I have an invention related to synthetic ammonia; how can I protect my intellectual property from being stolen? > I said there: Production can be increased significantly, or in other words, the amount of equipment needed to achieve the same level of production can be greatly reduced, while also saving energy and other resources. I hope it can be put into use as soon as possible and made public at an early date to achieve significant economic benefits. However, in an environment where corruption and plagiarism are rampant, I’m worried that it might be stolen; even hiring patent agents or the patent office isn’t a guarantee, as there are reports online of such thefts occurring. What do everyone think we should do? Thank you! ! ! Actually, the content of those previous posts all comes from my manual, or rather, monograph, on this invention. It’s even a complete direct copy. Let’s copy another passage now: Whether it’s the formulas in the \"Process Design Manual for Small Nitrogen Fertilizer Plants\" or those in the \"Synthesis of Ammonia in Large-Ammonia Plants\" manual, they all refer to the conditions at chemical equilibrium. However, in the production of ammonia, we cannot wait for chemical equilibrium to be reached; instead, at a certain space velocity, that is, after a certain amount of time, the chemical reaction is stopped before equilibrium is achieved, and the gas is then cooled outside the reactor to begin separation. In fact, to date, synthetic ammonia has been theoretically studied only in terms of equilibrium states, while in practice, only the ammonia yield from the tower is considered. The books devote a great deal of space to discussing the equilibrium in ammonia synthesis, but this is actually not very useful. They never explain how to calculate the amount of ammonia that comes out of the reactor. In almost all textbook problems related to ammonia synthesis, the amount of ammonia exiting the reactor is already known in advance, and then calculations are performed regarding aspects such as the yield of synthesis, which are also not very practical. The effects of inert gases and the role of ammonia entering the tower have also only been described qualitatively up to now. Example 8.3] is just like that. (Example 8.3] is an important example from \"The Production Process of Ammonia in Large-Scale Ammonia Plants\".) It can be said that although Haber’s invention of the ammonia synthesis process in 1912 was a great achievement, it led the ammonia synthesis industry down a wrong path; in theory and in practice, the problem of ammonia synthesis was not truly solved. The production of synthetic ammonia relies mainly on the results of practice. Theoretically, it is always assumed that the hydrogen-to-nitrogen ratio is one to three, and at equilibrium, in practice, one never waits for equilibrium to be reached; instead, there is a certain space velocity, that is, a certain amount of time. Practice also shows that a hydrogen-to-nitrogen ratio of 1:3 is not the optimal one; in practice it is always a bit lower, and the optimal ratio suggested by different people varies. Some say 2.8 is the best, some say 2.7 is the best, some say 2.6 is the best, and some say 2.4 is the best. These differences are actually caused by variations in the equipment they use, as well as factors such as temperature, pressure, catalysts, the structure of the synthesis process, the amount of inert gas, and the initial ammonia content. Now, in fact, everything should start from scratch, from Haber’s era. If I had lived in the same era as him, I would have followed my own inventions and not adopted Haber’s method. The results will definitely be very different. And it is conducive to solving problems theoretically. Some might say: So have you solved this theory? My answer was: No! They shouldn’t make this request of me either. Since true knowledge comes from practice, and since for over a hundred years people have adhered to Haber’s methods without wavering, continuing to work along a wrong path that hinders them from arriving at correct theories, it is naturally impossible for me to propose any correct theories as well. However, identifying a problem is half the solution; so let’s consider this my Goldbach Conjecture! It can only be discovered once people’s practices move away from Haber’s misunderstandings. It’s as if we can’t expect Watt to come up with the Carnot theorem. Of course, previous practices can also bring people a step closer to the correct theory. Theoretically, a hydrogen-to-nitrogen ratio of 1:3 is assumed, but in practice it turns out that a ratio lower than 1:3 is better – this is a significant finding. Strangely, among those who discovered their optimal hydrogen-to-nitrogen ratio, no one seemed to go further and investigate what the results would be at different space velocities, not at a ratio of one to three, but according to their own optimal ratio If that were the case, then we would already have a great deal of data: there is data provided by him suggesting that 2.6 is the optimal value, data indicating that 2.8 is optimal, and data showing that 2.4 is optimal as well... Moreover, each of them has specified their own production conditions... Perhaps in the end people will not produce at these hydrogen-to-nitrogen ratios, but rather at lower ratios, achieving results that are beyond our current expectations. It definitely won’t be three to one. Now, I hope that all those who have had such experiences will come and share their stories. For example: under what conditions, such as temperature and pressure, is the optimal hydrogen-to-nitrogen ratio, as well as the space velocity, inert gas, initial ammonia level, and ammonia level at the exit of the tower. For any incidents that occurred due to an imbalance in the hydrogen-to-nitrogen ratio, or incidents that nearly happened, please share details such as the hydrogen-to-nitrogen ratio at that time, the space velocity, the amount of inert gas, the initial amount of ammonia, the amount of ammonia exiting the tower, and the temperature drop, among other things. Only by gathering these valuable experiences and lessons gained through practice can we arrive at correct theories. Everyone provides information, and then we summarize together. Strive to elevate it to a theory to guide practical production.