Siheyuan: I eat melons while doing scientific research

Chapter 1276 Getting the Standard Coal Back (4k, 12k today)
There are naturally many problems, since every technology has its own flaws, though some flaws are large and some are small.

The biggest problem is naturally the defects that may affect the quality of the steel. The most obvious and easiest to think of is uneven composition, which is a major taboo for anyone working with various materials in most cases.

Have you analyzed the possible causes?

"Oxygen blown down from the top only creates an impact zone on the surface, which is hardly enough to fully agitate the molten steel and can easily exacerbate stratification of the molten pool." The comrades are quite clear about this problem; it's simple.

Gao Zhendong shook his head: "More than that."

"more than?"

"Yes, top-blown converters mainly rely on the reaction of carbon and oxygen to generate carbon monoxide gas to stir the molten pool. At the beginning, the carbon-oxygen reaction is insufficient, and even when the carbon is consumed in large quantities near the end, it is still insufficient. At this time, the stirring intensity decreases, which will cause unevenness." It is easy to understand that the oxygen lance at the top can only blow the molten steel below to impact the surface, but what Gao Zhendong just said goes a bit deeper.

However, in principle it is still not difficult. The chief engineer of Beijing Steel Plant nodded repeatedly: "You are right, we have been thinking too simply."

Gao Zhendong laughed and said, "In fact, the problems of uneven chemical composition and temperature, difficulty in slag formation, long smelting cycle, a lot of smoke and dust, and high oxygen consumption in top-blown converters all stem from this one reason: insufficient stirring capacity."

Upon hearing Gao Zhendong's words, the comrades immediately remembered a major problem with the existing converters—the long smelting cycle.

It turns out the roots are here!
However, they found it strange that Chief Engineer Gao, who hadn't participated in the actual production of converters one and two, was so clear about these defects. "Different things are different," they thought, "he could guess everything just by analyzing and estimating!"

"So, how do you think we should handle this problem?" Sure enough, Chief Engineer Gao still couldn't stand any of the furnace's defects. Once the biggest problem was solved, he would have time to deal with everything else. It turned out that he hadn't called our colleagues over for anything related to his own research project; it was purely to solve the problem with the converter at Beijing Steel Plant.

"I bet you've heard of this before, right? Be bold, the method is actually very simple, just reverse the problem from the beginning, right?"

Gao Zhendong's words immediately made the chief engineer of Beijing Steel Plant realize that although he had not studied some of the technologies due to their difficulty, environment, and adaptability, he was still familiar with them.

"You mean bottom blowing?" Chief Engineer Gao had already made it very clear.

Since top blowing can only blow on the surface, we can blow from the bottom up. This allows oxygen to pass through the entire molten pool and fully react with the carbon. At the same time, blowing from the bottom up allows the oxygen itself to move and better stir the molten pool. Combining these two methods, the whole problem can be said to be solved!

"Yes, it's bottom-blowing. Or rather, incomplete bottom-blowing, top-bottom combined blowing! After all, bottom-blowing also has its flaws. Combining the two will minimize the problems." Only children make choices; adults want it all! Gao Zhendong decided to go all the way. After all, once bottom-blowing is done well, the difference between bottom-blowing and combined blowing is just one step away, and top-blowing is already ready!

Top-and-bottom blowing accounts for more than half of my country's steelmaking furnaces in the 21st century, and there are reasons for this. As the world's largest steel producer, and one that once managed to compete with the world's second-largest steel producer simply by having various regions underreport their output, our choice in this area is absolutely trustworthy.

Gao Zhendong's experimentation with converters was aimed at solving the production efficiency problem of bulk steel, so naturally he chose the type of converter that would be used most frequently in the future.

"Top and bottom re-blowing? Isn't that a bit too complicated?" Director Fan of Jinggang Steel Plant felt that they were taking a bit too big a step.

"It's complicated, but not unacceptably so. Theoretically, it's just a combination of top-down and bottom-up. Instead of bottom-up, it's better to go straight to the point and do whatever you want." When it's time to take a big step, Gao Zhendong doesn't hesitate at all.

That seems to make a lot of sense. Comrades, we're infected by Gao Zhendong's optimism. Yes, what's this about top-bottom reversal? It's not that weird. It's just a combination of the two, and it's highly adaptable. It can adapt to many types of steel, so you can do whatever you want with it.

The comrades nodded in agreement. "That's a good idea!"

However, the chief engineer of Beijing Steel Plant knows more about this: "According to foreign research and literature, bottom blowing has a great impact on furnace life and requires high precision control of oxygen flow. It requires simultaneous control of the airflow parameters of top blowing and bottom blowing. Isn't that asking too much of our workers? The high operational difficulty also greatly affects productivity."

Bottom-blown furnaces are prone to coking and require cleaning, and the bottom oxygen lances need to be replaced more frequently; these are all factors that affect furnace lifespan.

Factory Director Fan patted the chief engineer's arm: "Have you forgotten what Section Chief Fang, one of Chief Engineer Gao's top lieutenants, is doing in our factory? Oxygen flow control and top and bottom dual control, isn't that exactly what he's working on right now?"

The chief engineer slapped his forehead, said "Oh~~~~", and laughed self-deprecatingly. He had forgotten, forgotten. The automatic control system was a bit new, and he always overlooked it.

Gao Zhendong also smiled and said, "The furnace life is affected to some extent, but it is mainly the oxygen lance and other accessories that are affected. The impact on the converter itself is not too great. Moreover, it mainly increases the working time for cleaning coke and replacing oxygen lances, so it is still worthwhile overall. Of course, bottom blowing also has many defects, and it can even cause uneven stirring, but these can be greatly suppressed by improving the process and using automatic control methods. Overall, top and bottom combined blowing is more beneficial than harmful. In addition, the stirring effect of top and bottom combined blowing is better. Under the current technical conditions, I have calculated that the steel yield can be 1 to 2 percentage points higher than that of top blowing."

The steel yield can be increased by 1 to 2 percentage points? Upon hearing this, the comrades were no longer sleepy.

They largely trusted Chief Engineer Gao's analysis; years of experience had proven his accuracy in this area, with a very high probability of his predictions closely matching reality. If the predictions differed significantly from reality, it was highly likely that there was some problem with the unit responsible for implementation.

In this respect, the comrades' trust in Gao Zhendong was that exaggerated.

The 1-2% steel yield that is likely to be achieved immediately excited everyone. Don't underestimate this small amount; it is actually a very good number. 1.5 tons more for every 100 tons of steel. What level is that?
As for the shortcomings, that's easy to address; we can overcome them. When conducting scientific research, we should focus on the main challenges.

No technology is perfect; if it is, it will most likely have one drawback: it's expensive.

The comrades, of course, understood this principle as well. After discussing and analyzing various aspects with Gao Zhendong, they unanimously concluded that this top-bottom re-blowing was worth pursuing.

The only problem now is technical.

Gao Zhendong's solution to this problem was simple, and extremely crude.

Smash it! Smash it with the documents!

Gao Zhendong produced a complete set of process data for top and bottom blowing, including not only pure oxygen top and bottom blowing but also a top and bottom blowing scheme that could use protective gas. Although it was relatively rough and some details were not clear, it was enough for the comrades to easily carry out their work. The most important parts of this were the overall process flow design, furnace structure, precautions during the smelting process, gas selection, reaction processes during smelting, and so on.

As for details such as the nozzle diameter, the number to be installed, the materials to be used, and the flow rate, the comrades at Jinggang Plant have plenty of ways to solve them. Even if they can't solve them, they have to, otherwise they would be embarrassed to even greet Gao Zhendong.

The comrades were all curious about where this came from, but Gao Zhendong simply said, "I analyzed it in my spare time. There was no practical process, so it is bound to have flaws. The specific implementation still requires the comrades to make detailed adjustments," and that was it.

Taking a break... the comrades felt the veins on their heads starting to bulge.

However, one cannot help but admire the fact that the analysis by Chief Engineer Ren Gao, although he humbly stated that it had not been put into practice, still appears flawless at first glance in terms of its principles, theories, and other aspects that do not require practical application.

After seeing this technology, the comrades at Beijing Steel Plant finally understood why Chief Engineer Gao hadn't brought it out last time. Last time, the improvement was on the converter's lifespan, not on the overall structure of the converter.

This top-and-bottom combined blowing system requires a complete and revolutionary overhaul of the converter, which cannot be completed in a short time. Chief Engineer Gao's arrangement is very reasonable: first solve the lifespan issue so that major steel mills can have converters in use, and then carry out further improvements, or in other words, build a new furnace!

Considering what Chief Engineer Gao just said about having "two technologies," it seems that he has high hopes for this new furnace.

"Chief Engineer Gao, you just mentioned two technologies. This is one. What is the other one?" Director Fan asked, speaking on behalf of the comrades.

Gao Zhendong did not answer directly, but instead asked a question first: "Director Fan, how much standard coal equivalent is the total energy consumption of water, electricity, ventilation, and gas used to produce one ton of steel in your converter?"

Energy is not just electricity and fuel. In fact, everything fed into the steel furnace is part of energy, although they are different, but they can be calculated using the method of converting to standard coal.

This is far more scientific and comprehensive than simply calculating direct energy sources like electricity and fuel.

This question stumped Director Fan, and not only him, but even the chief engineer of Jinggang Steel Plant, who was in charge of technology, was stumped.

There's no problem with the direct energy consumption; they can all give a straight answer, including every comrade from the Beijing Steel Plant here. On the other hand, Gao Zhendong himself might not be very clear about it because the information he has is from a different time period, so the figures might be different.

However, Chief Engineer Gao's question was too tricky, requiring calculations to take into account water, gas, wind, and so on. This method was not commonly seen these days.

However, what the comrades admired was that although Chief Engineer Gao's question was tricky, it was scientifically sound!

On the contrary, our group didn't consider this when calculating energy consumption; our thinking was not as comprehensive as theirs.

Doesn't wind come from wind turbines? Don't wind turbines consume energy? Not considering this aspect is indeed an oversight. Similarly, the same applies to water, air, and so on.

I haven't learned the technology yet, but I've learned how to comprehensively calculate energy consumption, so it's worth it.

Alright, what are you waiting for? Let's get started!

Fortunately, the people here are all technical backbones of Beijing Steel Plant, with very solid skills and experience. They have an exceptionally clear understanding of every step in the entire smelting process, including the water head and flow rate, the fan power, and the gas velocity and flow rate. All of this data can ultimately be converted into standard coal equivalent.

Comrades, we took turns calling out numbers, writing them down and calculating them on the blackboard in the meeting room. After working for quite a while, we had someone else check the calculations before we finally gave Gao Zhendong a number, feeling a little embarrassed.

"Chief Engineer Gao, it's about 30 kilograms of standard coal per ton of steel."

Gao Zhendong looked at the number and laughed: "What if we have a way to get those 30 kilograms of standard coal back from the converter while completing the steelmaking process, or even more, to achieve negative energy steelmaking? What do you guys think?"

Ok?
The colleagues at Jinggang Steel Plant almost thought Gao Zhendong was talking nonsense and spouting rubbish.

Trying to get something for nothing? Even in technology, there are fundamental principles. Ever heard of the law of conservation of energy? Just look at the molten steel in the converter; it's simply impossible. You're even trying to extract it from the inside out—like reversing the electricity meter, are you?

Steelmaking does generate a lot of heat, but recovering this heat is impossible. From the perspective of converter structure and steelmaking process, it is technically infeasible. Moreover, arbitrary heat recovery may have a significant impact on the steelmaking process, directly affecting the quality of steel or even making steel impossible, which would be a losing proposition.

But this was Comrade Gao Zhendong. Thinking of this, the comrades wisely refrained from refuting him. However, the chief engineer of Beijing Steel Plant asked, "Chief Engineer Gao, could you be more specific?"

Gao Zhendong pointed to the calculation process on the blackboard and said, "What is energy? Here, it is mainly expressed in two ways—power and heat, right?" Actually, these two things are the same, but their macroscopic manifestations are somewhat different, so they can be calculated separately here.

"Yes." Even a fool would know that.

"Are these two things among the byproducts of steelmaking?"

Power? Heat?
Comrades, my head feels so itchy, like it's about to grow a brain.

"Chief Engineer Gao, are you referring to steam and gas?!"

The steelmaking process produces a lot of steam, and the carbon-oxygen reaction produces a lot of coal gas. Unexpectedly, Chief Engineer Gao had his eye on them.

Gao Zhendong nodded: "Yes, that's it! I said to bring the energy back, not to directly recycle it. As long as it's an energy carrier, it's fine. Although this energy can't be directly used for steelmaking in the converter, it has many other uses. Using it elsewhere reduces the energy consumption in other places, which is like a transfer payment, hahaha." Gao Zhendong laughed heartily, cracking a little joke with his comrades, which put him in a good mood.

(End of this chapter)