Steam preheating in coking coke towers

It seems like your steps are just wasting time, though it does take a while!

There really is no such step; after pressure testing, direct preheating is sufficient. There’s no need to use steam for preheating, as that only increases the energy consumption of the equipment

Its advantages are: 1. Removes all air completely； 2. Leaks can be detected before oil and gas enter, making it easy to address them. The downside is, of course, the massive waste of steam.

We raise the temperature of the tower wall in the steam-air expulsion unit to around 100 degrees; once a large amount of steam is observed coming from the breather valve, we then close the breather valve and conduct pressure testing as well as heating of the oil and gas tower. I feel like the steps you mentioned are a bit different; do you first perform pressure testing and then use steam to remove air? This air expulsion function should be sufficient to achieve the effect of a preheating tower. (The steam in our system partially enters the convection section of the coking furnace, where it causes overheating. I’m not sure if you have a design for this; such a design might help accelerate the preheating process of the tower.) I’m a beginner – I’m just sharing my own opinions on this issue. If there are any mistakes, I hope experienced colleagues can point them out to me

I’ve heard of this for the first time; we don’t have this step because it would be too wasteful of steam – preheating with oil and gas is completely sufficient； As for the sealing of the top and bottom covers, it can be fully tested during pressure testing.

In fact, the preliminary preheating of the carbon tower is completed during the pressure testing process

Is saturated steam or superheated steam used for pressure testing? It may be difficult to heat saturated steam to 120–150 degrees, and even if it is heated to that temperature, the steam is wasted. Heating superheated steam to 120–150 degrees should be no problem. Controlling the temperature at 120–150 degrees should primarily aim to minimize the impact on distillation.

There is no need for steam preheating; it is purely a waste of energy. Direct preheating with oil and gas is sufficient; step-by-step preheating is not required.

This is still beneficial for the equipment, as it helps to extend its service life; however, it increases the energy consumption of the device. In our unit, as well as in all coking plants I’ve seen, oil and gas are preheated right after the pressure testing is completed. In fact, when preheating oil and gas, it is also possible to achieve this goal by starting at a slower speed.

There is no need for steam preheating; the initial preheating of the carbon tower is completed during the pressure testing process. An air expulsion step must be carried out before pressure testing.

There’s no need, right! We have tried this; having a large amount of water in the coke tower has a significant impact on distillation during preheating and oil separation.

A few days ago, we operated our unit at low load, with only about 45% fresh feed. We tried the method provided by Bai Ding at that time; our main concern was that there might not be enough distilled oil and gas during preheating. The steam temperature was around 280 degrees Celsius, and after expelling the air, we used steam for preheating for over an hour, but the results were not very satisfactory.

This post was last edited by Bai Ding on 2009-5-1 22:33. 13# North of the city north: Our steps are: sealing—(no air expulsion step)—pressure testing—steam preheating (overflow line)—pressure release—preheating of oil and gas. It seems like no steam is wasted either; it’s just that the time taken to preheat the oil and gas from the cover to the outlet is longer.

It should be there. What you’re referring to is actually the preliminary preheating of the air-coked tower; it’s just that you’re taking too much time, which results in steam waste

There is absolutely no need for steam preheating; gas can be filled as long as the pressure test is successful. This reduces the water content in the preheating oil, and at the same time minimizes the fluctuations in distillation processes caused by that water content

It’s not to expel air; expelling air should be done before pressure testing

Actually, \"pushing air\" means steam preheating. With a capacity of 1.2 million tons per year and four furnaces along with two towers, 15 minutes of air pushing is sufficient

There’s no need for that; it’s a waste of steam； Just purge the air and conduct a pressure test ； The air expulsion is generally controlled between 15 and 30 minutes.

In my opinion, it’s completely unnecessary. By now, the technologies and equipment used for delayed coking are highly mature; if no leaks are detected during pressure testing, then there’s no major problem. It’s too wasteful