Under rudimentary conditions, small blast furnaces are usually used for iron smelting, and as long as the performance of the blast furnace is stable, relatively pure iron can be smelted and become a raw material for steel.

The main raw materials for ironmaking are: iron ore, coke and lime; Iron ore, coke and limestone are distributed into a charge according to a certain proportion, and added into the furnace in batches from the top feed inlet, and the preheated air is blown into the furnace from the air inlet at the bottom of the furnace belly.

Because the hot air rises from below and the charge falls from top to bottom, they are in full contact in the furnace so that the reaction can proceed smoothly. At the same time, the charge can be gradually preheated, so that the heat can be fully utilized; In the vicinity of the air inlet, the coke burns with hot air, which generates carbon dioxide and releases a large amount of heat.

Carbon dioxide gas rises and reacts with red-hot coke to form carbon monoxide. The carbon monoxide gas rises again, following the iron ore that is constantly loading and gradually falling from the furnace roof, and in the middle of the furnace body, most of the iron oxides are reduced to iron by carbon monoxide.

During the smelting process, elements such as manganese, silicon, sulfur, and phosphorus mixed with iron ore are also reduced from their compounds by carbon or carbon monoxide.

A small amount of carbon, manganese, silicon, sulfur, phosphorus, etc., is fused in iron at high temperatures to become pig iron, and the melting point of pig iron (about 1200 degrees Celsius) is much lower than that of pure iron (1535 degrees Celsius).

In addition to iron oxides, iron ore also contains refractory gangue, if they are not removed, it will affect the smelting of pig iron, and limestone is added as a solvent to remove gangue.

Because the calcium oxide decomposed of limestone at high temperature can react chemically with the silica in the gangue to form calcium silicate with a low melting point, which is separated from the ore.

Small blast furnaces, once all over China, were gradually replaced by large national steel-making plants and completely withdrawn from the market because of their low production capacity and high environmental pollution.

However, it is not difficult to get a set, and there are still small blast furnaces on the market, all of which are very advanced special metallurgical blast furnaces for smelting precious metal ores, and the versatility and automation are very high.

Liu Yu is ready to get a few sets of cheaper ones, plus the small and medium-sized electric steel furnaces purchased in Detroit, USA some time ago, which are fully capable of producing high-quality steel, and even special steel!

He also purchased a large number of high-precision machine tools, as well as other industrial equipment, which can produce a lot of things, such as firearms and artillery, mechanical parts, building materials, and rolling steel, including all ordinary steel products.

You can also add some chromium to produce stainless steel, which has a wider range of applications, including screws, kitchen knives, steel sheets, and small steel pipes; From artillery to armor, steel bridges, and railroad tracks, everything is planned.

………

In contrast, the task of manufacturing cement is more important, building roads, building houses, building cities, and building airports, all urgently need cement, and the demand is very huge, at least one million tons in the short term.

To produce ordinary cement, there are five kinds of raw materials, namely limestone, gypsum, clay, iron ore powder, coal, etc., of which limestone is the most and gypsum is the least.

The process, mainly crushing and pre-homogenization, raw meal preparation and homogenization, preheating and decomposition, clinker firing, cement grinding and packaging, requires a lot of heat and electricity.

Electricity, mainly used for grinding powder, because the raw meal needs to be ground in advance, and after firing, the cement must be ground into powder again, which consumes a lot of electricity.

In order to provide sufficient electricity, Liu Yu decided to build a small thermal power plant to supply the power needs of factories and cities, and complement the advantages of wind turbines and hydropower units developed in the future.

To the south of the Xiqian Mountain is the Yellow River, which has abundant water in all seasons, and it is certainly no problem to build a small and medium-sized hydropower station, and there is no need for a dam.

For now, it seems that at least one power plant, one cement plant, one smelter, and an attached machinery plant are needed, as well as at least six mines.

……

Mining work was the first arrangement, exploration and mapping was the first step, Liu Yu returned to the camp in the west of the mountain, recruited a team of elite cavalry, a small team of members, and drove to the Gahai Coal Mine dozens of miles away on horseback.

The Xilushan area, which used to be a buffer zone between Datang and Tuyuhun, was sparsely populated, or there was no one at all, and there was no such development on both sides.

It is difficult to move forward for dozens of miles, but fortunately, Liu Yu arranged a crawler excavator to open the road in front, followed by four mining trucks, and pressed all the way over, as if walking on the ground. The Corps Iron Cavalry, who is familiar with the terrain, is responsible for identifying the position and acting as a guide.

Modern maps, ancient maps, and satellite real maps refer to each other, and it can be roughly determined that the Gahai Coal Mine is located in the northeast, 45 degrees, about 20 kilometers away, in the middle of a hill.

After turning around and turning around, an hour later, the survey team finally arrived at the target location, and it should not be wrong to look at the mountain and terrain. It's just that now the green mountains and green waters look much more beautiful, with green trees and red flowers, and grass and warblers flying.

Between the hills, there is an open land of hundreds of acres, which is the coalfield area, and the lush pasture grass is more than half a meter high, and many pink azaleas grow.

"Where there is coal, there are azaleas, and there is a certain truth!" Liu Yu got out of the car and muttered to himself.

A member of the team next to him heard it and asked with interest: "Boss, do you mean that where there are azaleas, there is coal?"

The others also looked at the boss, wondering if that was the case; In fact, it is definitely not, the rhododendron belongs to the special plant in the indirect prospecting sign, and the probability is not particularly high, so it can only be used as an auxiliary judgment.

"No, not necessarily, where there is coal, there are azaleas; But where there are azaleas, there are not necessarily coal mines, and science is not easy to explain. ”

"Oh~ I see..."

Dozens of people worked in a hurry, and two tripod turning machines with a diameter of 20 centimeters were erected in predetermined positions. The position that Sao Nian chooses at will...

Several sections of five-meter drill pipes are connected and loaded onto the transfer rig; The diesel engine starts and starts spinning at a low speed of 20 revolutions per second, making it easy to penetrate the grass.

Wet soil, without much resistance, can easily drill into, quickly submerge into the half-cut drill pipe, roll out a large pool of mud slurry, obviously black.

"Dada~~"

Suddenly, one of them shook violently, and the drill bit was blocked by Yanzhòng, obviously drilling into the underground coal seam, and because the rotation speed was too slow, it could not be eaten at all.

"Stop, stop, pump, hurry!"

Liu Yu made a gesture to stop the team member operating the transfer rig and pull up the drill pipe; A large number of people gathered around the wellhead to observe, a large black piece of mud, there was nothing to see in it, but there must be coal!

"Yes, yes, this should be bituminous coal!" There are also cinders on the drill bit, which are finely crushed and shiny, and obviously belong to bituminous coal.

Theoretically speaking, bituminous coal has a high sulfur content, a long combustion flame, a lot of smoke, and a lot of pollution, which is worse than anthracite, but it can coke!

Coking coal is essential for metallurgy, and steelmaking is made with coking coal, not coal; As for anthracite, it can't be coking, if it's anthracite here, Liu Yu may have to die of anger~

… To be continued...