Can catalytic cracking be carried out without removing the large blind flange?
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In coaxial catalytic cracking units, large blind plates must be removed and installed during startup and shutdown phases, and this is a very dangerous task. I heard from some experienced engineers that foreign catalytic cracking units are equipped with control valves in this area, which is very convenient during startup and shutdown. Let’s discuss: if control valves were installed at the blind flanges of the oil and gas lines during startup and shutdown, how would the entire process of starting up or shutting down the unit proceed? How much in advance is it possible? What conveniences will it bring?
In principle, it’s possible, as long as it’s turned on fully and turned off completely! But do you think a valve that needs to be turned on and off once per cycle is worth using as a control valve? How to handle malfunctions and many other issues. Perhaps the master just said it casually; you should also consider the rationality and feasibility of what he proposed.
Even perfect control valves will experience wear over time during use; moreover, the linear speed at the blind plate is very high, which also contributes to wear. What’s more important during startup and shutdown is safety! Safe external circulation of the tower during startup! Returning the oil during shutdown also prevents the fractionated oil and gas from flowing back!
"Safe external circulation of the tower during startup! Returning the oil during shutdown also prevents the fractionated oil and gas from flowing back! " Great! ! Very powerful
The oil and gas pipelines of small devices are thin, so valves can be used, but they can only be employed once during operation; the cost of protection measures during startup is high, and blind flanges must also be installed when shutting down. It won’t actually save that much time. Moreover, according to safety regulations, if there are valves in this area, a safety valve must be installed at the top of the reactor. It turns out that someone in Oil& Gas magazine wrote an article for a comparative analysis. Personally, I think that as long as it is organized properly, removing and installing large blind plates does not take much time, and safety is absolutely guaranteed.
What was said on the 6th floor is correct; I completely agree.
As I understand it, the use of large blind plates is primarily driven by economic considerations. I’ve seen the translated Esso design guidelines, and there are many places where blind plates are used, mainly to save money. To put it simply, foreigners attach great importance to the economy; according to statistics, only one out of ten technologies is economically viable. For example, maglev trains were not implemented in Germany due to economic unviability ； But in the domestic market, it’s not necessarily the case – even if the investment isn’t recovered for a hundred years, its value will still rise!
The analysis on floor 8 is very good. For domestic projects, in most cases, **a large amount of investment is involved; whether that investment can be recouped is not the key issue. What matters is that with such projects, the enterprise, the region, or those people have something to do and money to spend................. Behind the competition over these projects in China lies a struggle among these **forces.
This post was last edited by mjl25mp6 on 2009-11-8 at 18:30. Let’s get to the point! Guys! That original poster, your master is wrong! Only the experimental setup has gate valves! By the way, how’s the chemistry that the original poster is pushing along? Learn the basics first before discussing the feasibility of technical upgrades!
First of all, your idea is worth encouraging; you can also look up some relevant information to see if you can find supporting evidence. Although foreign countries have a high level of equipment manufacturing, such valves remain unreliable for a plant with a construction period of over 4 years. Perhaps my knowledge is insufficient, and I haven’t come across any reports on this topic yet.