Cement, to some extent, is inseparable from almost all modern buildings. It can even be described as the foundation of the building.

Originally, thanks to the hundreds of tons of cement on the space construction site, Shi Yiwen didn't worry about cement, but now that the cement is running out, there is only one way left - manufacturing.

By the industrial standards of the 21st century, the manufacture of cement requires a lot of specialized mechanization – crushers, rotary kilns, ball mills, and so on. With the current capacity of the iron factory, it is obviously impossible to make such a large equipment.

If there are no conditions to create conditions, foreign laws will not work, so then local laws.

Thanks to the large number of old books in the library, which are actually electronic versions of old magazines and books, Shi Yiwen easily found the process of producing cement by soil method.

Originally, he thought that firing cement was a very complicated process, but in the "Building Materials Industry" in '58, he found a brick and tile factory in Xi'an, using local clay and nearby chalk, anthracite and gypsum as raw materials, calcining in an earthen kiln that burned green bricks, and produced the No. 150-200 cement process.

Its process is very simple, the mix ratio of raw materials is also very simple, that is, 100 catties of chalk, 8 catties of red clay, 15 catties of anthracite, the amount of gypsum added is 3%, first of all, the chalk, red clay and anthracite three raw materials are ground into fine powder, 33% of the water is added, adjusted into mud, and then kneaded into a 7 cm size ball, after drying, loaded into the cellar of burning green bricks for firing, calcining temperature of 600-800 degrees Celsius, there is no need to use the brick cellar production of burning refractory bricks. The firing temperature of the wheel cellar where the red bricks are fired is below 1200 °C, and the maximum temperature in the general firing system is about 1100 °C. The sintering temperature of red bricks is 1000°C. In fact, this is also the temperature limit of clay bricks, the wheel cellar is built with clay bricks, and the clay bricks will melt at 1400°C, compared to 1450°C, which is required to fire Portland cement.

However, in order to improve the life of the wheel cellar when building the cellar, the internal cellar will still be built with refractory bricks, just like the wheel cellar under construction, the cellar is built with refractory bricks, because the iron furnace and other places on the iron factory have always needed refractory bricks, in fact, there is a small brick cellar in the iron factory, specializing in the production of refractory bricks. If you want to produce high-grade cement, you really need to use the vertical cellar that burns refractory bricks. But not at the moment.

But right now, for Shi Yiwen, what he pursues is enough. Just like the mill needed to grind clinker balls, it is a hydraulic ball mill, the grinding ball is a cast iron ball, only the body is formed with wrought iron rivets, which can be loaded with a thousand catties at a time, and it only takes a few hours to grind into the required fine powder.

In fact, for the manufacture of ball mills, the iron factory has long been familiar with the road, after all, the sulfur and potassium nitrate used to produce gunpowder need to be ground into fine powder, but wooden balls are used there. Now it's just a matter of borrowing from the following principles.

But only a few days, when the brick-red chimney of the wheel kiln factory spewed billowing black smoke into the air, a few hours later with tons of cement pellets were transferred out of the cellar, after cooling, those pellets were sent to the ball mill, mixed with 3% white lime, after a few hours of machine grinding, thousands of catties of cement material were poured out.

After 180 mesh sifting and sifting, Shi Yiwen immediately instructed Xu Guangqi to mix the cement with water, and the masons used it to build a wall in full view.

"It's the same cement we used before!"

Sun Mingan seemed very excited, he had always been very curious about cement, and he didn't know how it was made, but he never thought that it was actually produced in a brick cellar.

As for the masons who have been working as bricklayers all their lives, they are even more stupid, although they were originally very curious about the "cement", after all, the things handed down by the ancestors are made of earth, lime and water and built walls and houses together, as for the dignitaries and dignitaries, it is just mud with rice juice. But what is used here is cement that is as solid as a stone after solidification, and what is even more incredible is that the "cement" is actually burned in the cellar, and then ground into powder, it becomes "mud".

This is too unbelievable!

Compared with the surprise of others, Shi Yiwen stared at the newly built cement wall and muttered to himself.

"It's about the same as cement 200 or more......

According to the information, if the cellar temperature is raised to 1300 degrees, the cement produced can reach No. 300.

"Guangqi, do you remember, how the tensile test mentioned in the book is carried out? There is also the bending test, you look at the Yumin and them, let the factory make some equipment, and then test the cement, and in the future, you can continue to improve the process and improve the quality of the cement. ”

Listening to the teacher's instructions, Xu Guangqi was naturally enthusiastic to devote himself to the new experiment, as for Yumin, he was a teenager in the village, and the young people often played together, so naturally he also taught them the mathematics, physics, chemistry and other knowledge he learned, and slowly became a "study group" of more than a dozen people.

Now of course, they are also encouraged to experiment, and these cements need to be tested as well. Although it has not yet been tested, it has been proven that the fired earth cement can be used to build aqueducts, and may not necessarily be used to build concrete buildings, but it is suitable as a binder for building materials.

With bricks and cement, the construction that had been suspended began again in full swing.

As spring turned to summer, when the weather was getting hotter day by day, finally, the first turbine was installed in the turbine workshop by the river, and almost as soon as it was put into use, everyone was stunned by its strong power, even with Edwin himself.

"Almost twenty horsepower!"

Talking to himself, Shi Yiwen saw that the extruder that was originally slowly extruding the bricks quickly extruded one brick after another, and the speed increased by no less than ten times. Not to mention the craftsmen of this era, but for Shi Yiwen, the speed of making bricks is unimaginable, and the increase in power has doubled the production efficiency, but now the only restriction on the efficiency of brick-making is probably how much clay the brick factory can mine. As long as the clay can be supplied, this wheel cellar brick factory can produce tens of millions of bricks every year.

And the wheel cellar on the banks of the Lugou River has even become a landmark here to some extent – the 15-meter-high red brick chimney is very eye-catching in itself, especially when it exhales smoke smoke, even from a long distance, it can be seen clearly.