Chapter 102: The Special Blast Furnace

Ultimately, the plan they decided on was to use a blast furnace to smelt ferrosilicon, and then a converter to make silicon steel.

He looked at the various plans on his desk and stretched. From the window, he could see the towering flames of the Ma Niao No. 1 and No. 2 blast furnaces in the distance. It was a bit of a waste to use these large blast furnaces to smelt ferrosilicon. For this reason, the Planning Department had specially approved a project to build another small blast furnace in the Ma Niao Steel Company specifically for smelting ferrosilicon.

The “Special” blast furnace was currently undergoing its second heating. Compared to the 125 cubic meter volume of the Ma Niao No. 1 and No. 2 blast furnaces, the Special blast furnace was a mini version, with a mere 30 cubic meters. However, because it was right next to the No. 1 and No. 2 blast furnaces, it could make full use of the high-temperature waste gas from these two furnaces, especially the specially built large hot blast stove.

These favorable conditions made it easy for the Special blast furnace’s smelting temperature to be raised to a sufficient level. Smelting ferrosilicon required a high temperature of over 1800°C, and hot air of over 500°C had to be continuously blown into the furnace body. This was a difficult condition for an ordinary small blast furnace to achieve, but it was not a problem for the Ma Niao blast furnace group, which had a specially built large hot blast stove.

Now, they only had to wait for the heating to be completed before they could test the first furnace of ferrosilicon. The raw materials prepared for smelting ferrosilicon had also arrived one after another: quartz sand, pig iron, coke… They were just waiting for the blast furnace to be started for experimental smelting.

The phone on his desk suddenly rang. He picked up the receiver. It was the foreman on duty at the front of the Special blast furnace. He reported that the intermittent coke heating of the furnace had ended, and they were now starting to add new coke and begin continuous, uninterrupted blowing.

“Very good, continue to operate according to the worksheet,” Ji Wusheng ordered. The heating work before this had already lasted for 48 hours. Ji Wusheng looked at the schedule. The first formal charging would probably begin in about 4 hours. He decided to go to sleep for a while. Once the furnace was started, he would probably have to stay at the front of the furnace for 24 hours straight.

Ji Wusheng woke up on time an hour before the furnace was started. He washed his face, changed into his work clothes, and a few apprentice technicians he was personally leading were already waiting for him outside the office.

The apprentice technicians were young men with some education whom he had personally selected from the steelworkers of the Ma Niao complex. They were currently being trained as foremen, and of course, they would have to take on more important work in the future.

But many of the good seedlings had been lost in frequent accidents. The Elder technicians were well aware of the dangers of working in front of the furnace and would generally try to avoid doing dangerous work themselves. If they participated, they would also take precautions. But the natives of this world, who had just come into contact with the monster of modern industry, had no intuitive understanding of it at all. Many of them did not live to the moment they were recognized by Ji Wusheng and had already turned into smoke and elements in the steel.

“Let’s go,” Ji Wusheng said simply after checking everyone’s work equipment. He boarded the commuter train that ran within the steel complex in front of the office building and headed for the blast furnace.

The Ma Niao Steel Complex was already taking shape. Although in Ji Wusheng’s eyes, this complex was quite shabby, by the standards of this world, it was already at a science fiction level. Just the iron rails on the ground, the iron frames and pipes in the air, and the forest of smokestacks were enough to make a native entering the factory area for the first time think they had entered some “demonic realm.”

Ji Wusheng got off at the “station” of the No. 2 blast furnace. He wanted to first check this new blast furnace that had been in operation for less than a year.

The No. 2 blast furnace was tapping iron. Accompanied by the ringing of alarm bells, a furnace flame over a meter long shot out from the taphole, the heat was intense. The firelight under the blast furnace was dazzling, and the molten iron inside the furnace churned and jumped, emitting a scorching glow. The molten iron was poured out, and sparks flew everywhere. The boiling furnace was like a “flaming mountain,” spewing hot flames. The molten iron in the furnace was like rolling lava, and from time to time, iron sparks splashed around.

In the workshop, the workers constantly stirred the red-hot molten iron, their sweat-soaked clothes clinging to their backs. Standing in front of the blast furnace, the giant mouth spewing red flames, five meters away, constantly pressed waves of heat towards them, accompanied by the occasional splash of steel sparks, the surrounding air also distorted. The outline of the blast furnace had long been swallowed by the red heat, and even the steelworkers working next to it, raising and lowering their stirring rods, seemed as if they would be swept into that great mouth at any moment.

Such a grand scene, even for an Elder in the midst of it, was thrilling. But for Ji Wusheng, it was a common sight. The volume of the blast furnace in front of him was less than a quarter of the one he had worked with in his old world.

The naturalized citizen workers worked in front of the blast furnace at over 1600°C every day. The temperature in the workshop was as high as 55°C, and they worked 12 hours a day in this environment, on rotating day and night shifts. Half of their time was spent in front of the high-temperature furnace. For safety, they wore Lin’gao-made protective goggles, safety helmets, large gloves, thick long socks, and other protective gear. They also had to wear thick canvas long-sleeved protective clothing, each piece of which was several times thicker than ordinary summer clothes. They were all blackened by the smoke.

But this full-body protection was only to block the splashing iron sparks. With just one slip, sparks would fly out, and a piece of red iron shooting out was like a bullet, fatal if it hit a person. With Lin’gao’s medical level, they could not treat the injuries of furnace workers.

Ji Wusheng felt beads of sweat rolling down his forehead. The average annual temperature in the blast furnace workshop was over 40°C, and in the summer, it could reach over 60°C.

The taphole was sealed again. The furnace master, Zhao Youcai, held a temperature gun in both hands and quickly came to the front of the furnace to test the temperature of the molten iron inside. If the temperature was too high, he would add material to the furnace; if it was too low, he would instruct the blower room to increase the blowing. At this moment, large beads of sweat flowed from under his safety helmet, and his protective clothing was completely soaked.

Zhao Youcai had come from Guangdong. He was not a refugee, but an immigrant who had crossed the sea on his own. He had originally worked as an iron smelter in Shaoguan. Because business had been slow recently, he heard that Lin’gao needed a large number of iron smelters, so he came to join them. He entered the steel plant and became a furnace worker at the No. 1 blast furnace.

He had worked as an iron smelter in the earthen kilns of the Shaoguan area for more than ten years and had accumulated rich experience. He could judge the approximate temperature by looking at the fire and smoke. Most of the old craftsmen who were blacksmiths and iron smelters had such accumulated experience, but this experience had neither standards nor specific numbers. After coming to Lin’gao and receiving systematic training and practical experience in front of the furnace, his experience was systematized and theorized. He was also a studious person and participated in the steel plant’s training class, becoming a key worker. His sensitivity to temperature soon caught Ji Wusheng’s attention. After being his “apprentice technician” for a period of time, Zhao Youcai became the furnace master of the No. 2 blast furnace.

“Sir—” Zhao Youcai saw Ji Wusheng and hurried over to greet him.

Ji Wusheng waved his hand. “How is it?”

“The second tap of this shift. Everything is normal. The conversion rate today is very good. I think it can exceed 1,” Zhao Youcai’s face showed a proud smile.

“Well done,” Ji Wusheng nodded. “You first hand over your work to the foreman on duty, and we’ll go to the Special blast furnace.”

Zhao Youcai went to handle the handover procedures. Ji Wusheng looked around the blast furnace at the production situation. The production of the two blast furnaces and one open-hearth furnace was still stable. Although the intervals for minor, medium, and major repairs were a bit short due to the problem of the furnace body materials, they had at least maintained continuous production, roughly meeting the current demand for steel from the industrial sector.

However, the shortage of special steel and profiles was still the main problem he faced. The quantity of steel produced was considerable, but the production capacity of the rolling mill that processed the profiles was far from meeting the current demand of the industrial sector. No matter what enterprise used it, they couldn’t directly use iron and steel ingots.

After solving the problem of silicon steel, we must find a way to self-produce some rolling mill equipment and expand the production scale of the rolling mill, Ji Wusheng thought.

In front of the Special blast furnace, the workers participating in the trial smelting had already gathered. After the heating work was completed, the workers were cleaning the slag and unburned coke ash from the furnace hearth. Ji Wusheng watched the workers’ operations and asked the foreman on duty:

“How is the condition of the furnace hearth?”

“Everything is normal, no damage found.”

Ji Wusheng walked into the material bin. The raw materials prepared for this trial smelting were already there: coke, quicklime, pig iron that had been pre-treated into rods, and quartz sand that had been crushed and evenly mixed.

Ji Wusheng knew that except for the coke, the quicklime, quartz sand, and pig iron had all undergone component testing by the Central Heavy Industry Laboratory and were prepared according to the optimal ratio. This pig iron was specially purchased from Guangdong and had been desulfurized and dephosphorized.

They didn’t use the pig iron produced by their own factory because the Tiandu iron ore itself contained a higher manganese content, so the pig iron smelted by the Ma Niao blast furnace also contained more manganese.

Smelting ferrosilicon and silicon steel required a manganese content of less than 0.35. A too high manganese content would affect the magnetic properties of the silicon steel sheets. Not only that, but silicon steel also required as few impurities as possible, especially low carbon, low sulfur, and low nitrogen. Therefore, the content of harmful elements had to be controlled in the first step of preparing ferrosilicon, so that the yield could be improved in the next step of steelmaking using a converter.

Ji Wusheng immediately ordered, “Start charging! Prepare to start the furnace!”

The workers began to fill the furnace hearth with coke, and at the same time, began to blow hot air into the furnace. As more coke was added and the blowing continued, the bottom of the furnace began to turn red, and the flame in the furnace hearth gradually turned from red to white, and finally into a strong white flame. Even standing on the observation platform, Ji Wusheng could feel the strong heat radiation. The workers began to add quicklime at a ratio of 3%-4% while adding coke, until the furnace hearth was two-thirds full.