The blast furnace is the most difficult part of the entire project. In order to build the blast furnace, a special team was set up to collect all technical information about the blast furnace structure, materials and construction methods. A 125 cubic meter blast furnace is more than ten meters tall and weighs several
Thousand tons, it is the largest industrial equipment that the elders have ever come into contact with, and its difficulty exceeds all previous industrial construction projects.
Structurally speaking, the blast furnace must meet two prerequisites: the charge can drop evenly; the furnace gas can rise evenly at all height sections.
The uppermost part of a modern blast furnace is the furnace throat, and the furnace materials are loaded into the furnace by a special charging machine above. In order to protect the furnace throat from being damaged by the collision of the furnace materials, a layer of steel bricks is inlaid on it. The furnace materials are added to the furnace throat and are immediately loaded from below.
The rising hot furnace gas is dried and preheated. The furnace gas is discharged from here through the pipe on the top of the furnace - this part must be sealed very tightly to prevent the gas that accounts for most of the furnace gas from leaking or returning and causing workers
poisoning.
Part of the discharged furnace gas will re-enter the blast furnace as fuel, and the other part will be transported to the hot blast furnace to heat the blast.
The furnace body is a cone with a small top and a large bottom. The volume of the furnace material expands due to heat after contact with the furnace gas. In order to adapt to this expansion, the furnace material can drop smoothly, so the furnace body gradually becomes larger from top to bottom.
This design is used to prevent the occurrence of material hanging. The most taboo thing about blast furnaces is the hanging of material during combustion. It not only wastes the material, but also requires a ceasefire and cleaning. In principle, the blast furnace does not cease fire production. Once the fire ceases, it will take a long time to resume production.
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The finer the smelted ore particles, the greater the edge gas flow, so that the blast furnace will not hang materials. The flow of the edge gas flow is related to the angle of the furnace body. In the process of the furnace charge falling, the heavier ore tends to fall vertically.
When the body angle is small, the ore will be far away from the furnace wall, and a large amount of coke will move toward the furnace wall. At this time, a loose annular belt will be formed near the furnace wall, prompting a large amount of gas to pass through to form a large gas flow. When the furnace body is too steep
, the opposite situation will occur - hanging materials will appear. Therefore, the angle of the furnace body angle is generally 86 degrees.
Below the furnace body is the furnace waist, which is a cylindrical part designed to eliminate the dead angle created by the furnace body. Below the furnace waist is the furnace belly. Due to the burning of coke, the furnace charge is continuously melted, and the volume of the furnace charge is increased. Therefore,
Its shape is larger at the top and smaller at the bottom. The angle of the furnace hearth is generally 76 to 82 degrees. Using a larger angle can reduce the friction of the furnace wall. At the same time, as the angle increases, the diameter of the furnace hearth expands and the coke is fully burned.
, improving the production efficiency of the furnace.
The bottom is the furnace hearth, which is where molten iron and slag are stored. The temperature in the furnace hearth is very high, and just using ordinary refractory materials is not enough. The temperature in the furnace hearth is enough to melt the refractory bricks in the furnace hearth. Generally,
The method is to install a cast steel or cast iron shell on the outer layer of the furnace wall, and install a serpentine cooling water pipe in the shell to cool and protect the refractory bricks inside. Because steel is difficult to cast - the fluidity of steel is very poor
After many studies, the people from the industrial port felt that they were not confident in making such a large steel casting. Finally, they decided to make the next best thing and make a large cast iron cooling jacket. Just this casting cost Xiao Bailang several
month time.
The air inlet is located at the upper end of the furnace. There are 8 air inlets in total. The air nozzles must protrude into the furnace wall. Since they need to be resistant to high temperatures, the furnace nozzles are made of bronze. There are cooling water pipes inside the furnace nozzles, which are also uninterrupted during operation.
Water is supplied for circulating cooling. The taphole is located near the bottom of the furnace, and above the taphole is the slag tapout. It is also made of bronze and cooled by circulating water.
The blast furnace not only has a large capacity but also produces continuously. The temperature of the furnace throat of a large blast furnace is extremely high. Manual feeding cannot be used, but mechanical automatic feeding. There are several ways to feed the blast furnace. Jiang Ye and Ji Wusheng decided to use it after discussion.
The simplest charging barrel charging method in the mechanical structure. The charging barrel is bell-shaped. Transport the hopper to the top of the furnace, then raise the barrel to the top of the furnace, block the top of the furnace, and then the charge is opened from the top of the furnace.
The bottom of the barrel leaks into the furnace throat. The hopper slides on the track through a crank link mechanism to drive the barrel. Although this system is not complicated, it requires the industrial system to provide reliable equipment in terms of chains, mechanical transmission and power machinery.
Jiang Ye said: "At the beginning, Zhan Wuya could not say that he only built converters for blast furnaces and imported pig iron from Guangdong to make steel. I also thought he was a bit of a right-leaning conservatism - now it seems that even if he wanted to build a blast furnace at that time, he might not be able to do it."
"At that time, it was only possible to build a three- to five-meter-high earthen blast furnace. Two to three tons of pig iron were produced in a day and night, and the top of the head was five tons. Most of the feeding was done by using a winch to winch up the furnace material, and then the workers shoveled it into the furnace throat.
Riga - The workers were beaten to death. The feeding was slow and the blanking was uneven. The efficiency was as bad as that of today's small chemical plants." Ji Wusheng sympathized with the owner of the chemical system. His owner's industrial scale
According to the standards of the old time and space, it is not even close to the county-level chemical plants of the 1970s. Many products are still manufactured at the laboratory level. If it were not for the coal coking joint production plant transported by air from the old time, it would still be a grand scene, just the 800 tons of synthetic ammonia.
The poor output of the electrolytic salt workshop made him roar at every Planning Institute meeting.
"Once our steel complex is put into production, we will probably use chemical equipment on a large scale. Your machinery department will have a heavy burden."
"What does this mean?" Jiang Ye didn't care. "Can we get some special steel or something? Especially stainless steel. It has to be used in too many places. There is also silicon steel, which is needed to make generators, motors and transformers. You
I don’t know that Mr. Chang comes to our place every three days and complains that there is no use for him in power construction.”
The electricity supply of Chuan Chuan Group is a fatal shortcoming. Whether it is power generation, power supply or electricity usage, it is probably at the level of small counties in the late 1970s - or even worse - it is not possible to build a county-wide power grid.
.The direct result of the lack of electricity is the proliferation of steam engine boilers everywhere.
"Your request is more difficult. We cannot get the non-ferrous metals needed for the former, and it is difficult to smelt the latter. However, manganese steel can be produced quickly - the iron ore in Tiandu itself contains high manganese, and there are also local
There is a manganese mine that can be mined." Ji Wusheng said, "Besides, Chang Gong has not been planning the East Asia Power Grid's ultra-high voltage transmission and transformation system, the Himalayan super power station, and the Yangtze River cascade power station development plan in his notebook - he can work as an electrician while first
Make a plan?"
"Although it is not as exciting as stainless steel and silicon steel, it is still good news." Jiang Ye said. Manganese steel has the characteristics of high strength and high wear resistance, and plays an important role in many large machinery. With the addition of manganese steel
The performance of currently low-quality bearings, gears, structural parts, and connectors can be greatly improved. Manganese steel can also be used to manufacture knives for industrial use and provide high-quality weapon steel for the military industry.
Next to the blast furnace stands a completed large-scale hot blast furnace - the 125 cubic meter blast furnace requires far more air blast than the several small converters and iron furnaces in the past. Bigger often means higher efficiency. The hot blast furnace is working on the converter
The steelmaking workshop has already been built, and we have considerable experience in construction and use. This time we have enough refractory materials, not only the volume has become larger, but the internal structure has also been optimized. The new hot blast furnace is a satisfactory Kaopa type hot blast furnace.
The furnace is up to 10 meters high. The hot blast furnace uses the high-temperature exhaust gas of the blast furnace to preheat the air entering the blast furnace from the blower. The design goal is that the air outlet temperature can reach 620c. At such a high temperature, the reducibility of iron ore will reach its highest level.
, coke consumption can be reduced by one-fifth.
"Gong Jiang!" A naturalized citizen intern hurried over, "I just called from the gas plant construction site and asked you to go take a look. There are some problems there."
"Okay, I'll be there right away." Jiang Ye and Ji Wusheng said hello and went down the hill. A farm vehicle had been prepared here.
The gas plant is an important project of the Ma Niao Consortium. The coal coking combined chemical plant put into use in Bopu can also provide gas, but because it has chemical equipment for subsequent processing and refining of gas and tar produced in coking, gas is generally
It was directly consumed as chemical raw materials, and a small amount of the remainder was given to the nearby Bopu Industrial Zone for use as fuel.
The gas plant does not use coking lignite specially transported from the Jiazi Coal Mine - the blast furnace coke is provided by the Bopu Coal and Coke Combined Plant - but uses a dedicated gas generator to retort various inferior coals. The purpose of its production is not to obtain coke.
But gas.
After the gas workshop is completed, it will provide gas fuel for the entire plant, and its main purpose is to provide fuel for open-hearth steelmaking - the calorific value of the gas produced in blast furnace smelting is low and cannot be used as fuel for the open-hearth furnace.
Different from the specialized large coke ovens in coking plants, the gasifier has a simple structure and is easy to operate. Moreover, the mechanical department also has a lot of experience in manufacturing and using gasifiers. There is no difficulty in manufacturing and using it.
After the coal is added to the generator furnace, it is ignited for carbonization and reacts with the air added from the bottom of the furnace to produce gas. However, the calorific value of the gas at this time is low. As an open-hearth fuel, the calorific value is low, so the boiler evaporator is used while coking.
The produced water vapor is mixed with air in proportion and then blown into the generator furnace to produce semi-water gas. The calorific value of semi-water gas is much higher than that of air gas and can be used as fuel for open-hearth furnaces.
The tar produced during carbonization is stored in a special tar tank and then transported to the coal and coke combined plant in Bopu for further refining. Ji Tuisi plans to install a tar treatment plant at the Ma Niao Gas Plant in the future to process coal tar on-site for chemical production.