The blast furnace is divided from bottom to top and is divided into the furnace bed, the furnace belly, the furnace waist, the furnace chest, the furnace throat and other parts. There is an iron outlet at the bottom of the furnace bed, and there is a slag outlet at the appropriate height above it, but the positions of the two openings are not on the same vertical line.

On the upper part of the furnace bed, a circle below the lower edge of the furnace belly evenly surrounds many vents and is connected to the pipes of the hot air furnace.

The blast furnaces in the Ming court were naturally not as high-end as modern, but they also had the prototype of modern blast furnaces.

"You and other craftsmen are all from the mainland and can stay in Luzon." Liu Yu did not ask about the situation of iron smelting first, but instead asked about the lives of these craftsmen and workers.

Liu Yu looked at the busy workers and craftsmen. These workers and craftsmen were all from Foshan, Guangdong, and were specially recruited by Lu Hai for the Ming Ting Iron Smelting Plant at a high price.

During the Ming and Qing dynasties, Foshan's iron smelting spread all over the world.

Foshan, known as one of the "Four Great Gatherings in the World", is famous at home and abroad for its iron smelting industry.

Naturally, it has the best blacksmiths and workers in the country.

"When I say that, we are all Foshan craftsmen. We were dissatisfied with the harsh Qing government and came to Nanyang with Lu Hai. Now we have monthly salary in Luzon, and the rice coupons are enough for our family of five to make a living. If it weren't for the kindness of our great man, how could we have the blessing of today?" Wang Qing said respectfully.

"Yes." Liu Yu nodded. The Ming court attached great importance to craftsmen. In addition to annual salary and monthly salary, there were also a year of rice coupons and other things.

"Now, my iron smelting plant mostly uses charcoal, right?" Liu Yu asked.

"Sir, Luzon is mostly wood, so we all use charcoal," said Wang Qing.

"Then do you think it is better to smelter charcoal or to smelter smelter with coal? If it is better to smelter smelter, I can let the four seas import coal from the mainland." Liu Yu asked.

Coal: In ancient China, there were different names such as charcoal, black firewood, black gold, wood stone, burning stone and mineral charcoal.

Liu Yu knew that later generations mostly used coking coal to make iron, and coking coal came from coal.

During the Ming and Qing Dynasties, China had already used coal to smelte iron on a large scale.

The "Compendium of Materia Medica" by Li Shizhen, a famous scholar in the Ming Dynasty, once said:

"There are also many places for the mountains in the north and south of the carbide, and people did not use it, so few people knew it. Now people use it instead of cooking and cooking, smelting iron and stone, which greatly benefited the people. The natives all dug mountains into caves, and took it more than ten feet across..." It can be seen that in the late Ming Dynasty, coal was the main raw material for iron smelting.

"Sir, charcoal and coal have their own advantages and disadvantages." Wang Qing smiled and replied.

"With coal smelting iron, the heat is fast, the output is large, and the mainland is more coal, but the pig iron produced is more impurities and the texture is brittle, which is not as good as charcoal smelting. Moreover, now we are in Luzon, so it is better to use charcoal according to local conditions," said Wang Qing.

Seeing that Liu Yu was a little disbelief, Wang Qing smiled and continued, "Sir, do you know why there were Mo Dao and Tang Dao in the Tang Dynasty, but they were all lost when they arrived in Song Dynasty?"

"Why?" Liu Yu became interested.

"That's because during the Han and Tang Dynasties, iron smelting mostly was made from charcoal from the Central Plains. Iron was smelted with charcoal. There were few impurities in pig iron and high quality. Therefore, during the Han and Tang Dynasties, famous knives were often made in the Central Plains. However, in the later period, the wood in the Central Plains was reduced a lot, and coal had to be used to replace charcoal. Coal could be used to smel iron. There were too many impurities in pig iron, so good knives from the Han and Tang Dynasties cannot be made today."

"You know that there are many large woods in Fujian and other places, so charcoal is used in iron smelting in southern Fujian, so the quality of Fujian iron is the best."

After hearing this, Liu Yu suddenly realized that it was no wonder that Japan's samurai sword crushed a mass of Chinese swords during the Ming and Qing Dynasties.

During the Ming and Qing dynasties, China used coal smelting, and the pig iron smelted was mostly impurities, while Japan mostly used charcoal iron smelting. After all, Japan had few people and a high forest coverage rate. It is even now the world's leading ecological power.

Therefore, Japan does not lack wood, so it naturally uses charcoal to make iron, and the samurai swords cast with iron are naturally excellent.

Liu Yu vaguely remembered that after entering Lavague, the Ming court repeatedly appointed the Sihai Chamber of Commerce to travel thousands of miles north to import pig iron from Japan because Japan's iron material is good.

"The quality of iron smelting with charcoal is so good. Why is the iron material in iron smelting plants so scarce? The firearms department even have enough iron materials for casting cannons?" Liu Yu frowned and asked when he heard Wang Qing exaggerating the charcoal smelting.

"Charcoal is a material for iron smelting, and the cost of producing one ton of pig iron requires at least two tons of iron ore sand, 130 kilograms of limestone and 7 tons of charcoal. The wood required is astronomical. In these days, the iron ore sand transported from Sihai has been piled into small hills, and the craftsmen are waiting for Sihai merchant ships to transport large wood to burn it into charcoal." Wang Qing said in a difficult face.

"It turned out that it was caused by the lack of charcoal." Liu Yu nodded.

The output of coal iron smelting was high and the Central Plains was abundant in coal, so in the Ming and Qing Dynasties, coal was used, and the supply of coal was continuously carried out. In addition, the high coal heat naturally made the production capacity of iron smelting remained high.

The amount of iron smelting charcoal is high. Although the smelting iron quality is high, the amount of charcoal required is too amazing and the natural yield is low.

During the Ming and Qing dynasties, China had to choose to use coal to smelter iron due to natural environment. The quantity was increased, but the quality was constantly decreasing.

On the other hand, if you want to increase your output, you must use coal. If you use coal, you must import from mainland China or Southeast Asia.

Not to mention the trouble of transportation back and forth, the source is easily cut off by the Qing court.

Liu Yu would never do anything to get stuck in the Tartars.

Now the Ming court can only pursue the quality of iron smelting and ignore quantity.

There is nothing to do, after all, Luzon has more charcoal than coal.

"Since my Ming Ting iron smelting plant uses charcoal to smelter iron today, I guess it is much better to transform pig iron into ripened iron than in the mainland, right?" Liu Yu asked again.

"Reply to the words of sir, this is natural." Wang Qing smiled.

"Cat iron is crispy and not easy to forge and can only be used as an agricultural tool. If it wants to mature iron, it needs to flow out of the iron smelting furnace to the iron smelting furnace and stir with willow sticks to turn into cooked iron." Wang Qing said while pointing to the iron smelting furnace beside him.

The so-called iron stir-frying furnace is actually a Western stir-frying furnace.

But the difference is that the stirring furnaces used by Westerners use cooked iron rods or steel rods to stir them, burning away the carbon from the pig iron and finally obtain cooked iron.

The Ming Dynasty used willow sticks, which were stirred by willow sticks. During the firing process, the willow sticks will gradually be burned due to high temperature and merged into pig iron, causing the pig iron to mix into charcoal, reducing the speed of removing charcoal, so that the iron stir-frying hand can control the iron content, thereby frying steel with a charcoal content lower than pig iron but higher than cooked iron. This is fried steel.

It can be said that during this period, China's iron smelting technology was actually ahead of the West.

However, after the Tartars entered the Central Plains, China's iron smelting technology stopped moving forward and was gradually overtaken by the West.

Unfortunately, during the Ming Dynasty, China's steel smelting had reached its top level, but it was still a little short of time, that was, to turn steel into molten steel.

Liu Yu went up and looked at the so-called iron stir-frying furnace.
Chapter completed!