Exploration of the Fourth-Generation Alkylation Modification for DuPont

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After coming into contact with DuPont’s latest version, there are many changes compared to DuPont’s third-generation alkylated version, but no further optimizations have been made yet. During the interaction, I had the following personal thoughts. First, for DuPont acid washing, alkali washing, and water washing processes, the deacidification coalescer was replaced directly. This approach was proposed in 2015; through efforts by various parties and with the approval of the leadership at Hengli Petrochemical, a deacidification coalescer was switched in, followed by treatment using polar alumina for adsorption. The advantage of this method is that it achieves deacidification through purely physical means. ………………The reason is the corrosion issues associated with the acid washing, alkali washing, and water washing processes used in the original DuPont version, which include acid corrosion, alkali corrosion, salt corrosion, as well as cavitation. The most severely corroded are the alkali washing tanks and water washing tanks. If there are many side reactions, in the alkali washing tank and water washing tank, the saponification reaction becomes more intense, and white foam appears in the wastewater. In practical use, the issue of replacing polar alumina trioxide. The issue of industrial waste. An economic cost issue was overlooked in this process. Whether to use one or two deacidification coagulators, the problem of acid leakage still exists. Because the sulfatides produced as side reactions in the alkylation reaction adhere to the internal components and inner walls, affecting the acid removal efficiency. It’s not that deacidification coagulators are necessarily effective. Therefore, subsequent adsorption by polar alumina will allow more acid to enter, reducing the operating cycle. The investment cost is not low, but it is possible to make better use of acid-removing coagulators, such as Lumar’s two-out-of-three mode. This deacidification coalescer performs best at lower reaction temperatures. After replacing the coalescer, it is even more necessary to lower the reaction temperature, as a relatively high reaction temperature leads to more side reactions. The formation of acidic lipids causes blockages in the deacidification coalescer, thereby affecting the efficiency of deacidification. Second, swap the locations of the fourth-generation DuPont energy-saving tanks. Apart from supplying air to the second-stage compressor, this energy-saving tank has almost no other functions. Based on the available resources, it can be placed behind the deacidification coalescer for secondary flash evaporation; the gas outlet remains unchanged and continues to supply gas to the second stage of the compressor. It can also be connected to the primary flash tank via the gas line of the secondary flash tank, thereby supplying gas to the first stage compressor as well. The temperature of the alkylated mixture after secondary flash evaporation will be lower. It can exchange heat with the refrigerant at the compressor outlet, as well as with circulating isobutane; the principle is to exchange heat with the refrigerant in order to further lower its temperature. Heat exchange with circulating isobutane results in a slight temperature drop. Reduce the heat load of the isobutane removal tower. This idea involves problems related to thermodynamic equilibrium calculations. If it goes directly into the isobutane removal tower, it will increase the heat load, resulting in unnecessary waste. Secondary flashing also reduces the heat load on the isobutane removal column, as it further decreases the amount of isobutane in the mixed product. I have worked with the DuPont process as well as the Lumas process, so I combined the advantages of both, further developing the DuPont process; secondly, both processes are viable. However, the second point has not yet been industrialized and exists only in imagination. As for what some people say – that those who know what they’ve done apply for patents in secret – this can be refuted. As for those who are superstitious about certain refining or design institutes, I refuse to discuss it. I also have more detailed information on this; optimizing the device requires continuous reference to different processes and self-learning*. It requires even more insight. If there is plagiarism, legal action can be taken. All devices are modular; the more devices you come into contact with, the more different equipment will provide you with various insights. Different designs have different approaches, and each design firm has its own strengths that we should learn from. Why can’t better discussions take place simultaneously in Project 3? Alkylation seems extremely simple, but how many people truly understand all the nuances involved, and how many really grasp the reaction mechanism in depth! Instead of bragging around, it’s better to settle down and study the techniques properly!