The most obvious advantage of fly ash cement is that the crack resistance is relatively good, and can withstand the erosion of the years, the strength of the later stage will exceed Portland cement, at present, the buildings in small places are mainly prefabricated panels, this type of cement is just suitable, he can even build a prefabricated panel processing plant by himself.

The so-called coal gangue is called coal sand and coal sand in Jiaoshan.

It belongs to the associated waste rock of coal, the carbon content is low, only 20%-30%, there is no way to burn in the ordinary furnace, and the texture is harder than coal, as long as it is digging coal, a large number of useless coal gangue must be cleaned up.

It is also called "coal sand seam" locally, because the coal gangue will be weathered and crushed after being exposed to the sun and rain for a long time; In addition, coal gangue will disintegrate after absorbing water, which is easy to produce dust, and even spontaneous combustion, emitting exhaust gases and polluting the environment.

After the coal gangue is weathered and crushed, the color will become lighter and crushed into small gravel, so it is called coal sand by the locals.

In the mountains of the Beidou area, although there are no open-pit coal mines, on some rock levels, you will see coal gangue layers of different thicknesses exposed to the air, and they will be weathered into sand after a long time, so the coal sand layer is a very appropriate name.

Fang Dajun had suppressed his excitement at this time, lit a cigarette, and continued to think, because this process was only briefly mentioned to use coal gangue instead of fly ash to process cement.

Fly ash and granulated blast furnace slag were originally purchased from outside, and there are steel mills in the county, so there will be iron slag, which is cheap and easy to buy. Coal dust is the fine ash captured from the flue gas after coal combustion, and is the main solid waste discharged from coal-fired power plants, and coal power generation is still the mainstream.

Fly ash contains: SiO2, Al2O3, FeO, Fe2O3, CaO, TiO2, etc., while the main components of gangue are Al2O3, SiO2, and Fe2O3, CaO, MgO, Na2O, K2O, P2O5, SO3, etc.

Among them, the judgment criteria are mainly Al2O3 and SiO2. Therefore, the use of coal gangue can completely replace fly ash as an active mixture of cement.

But in order to make the gangue active, it also needs to be calcined, but because the gangue itself contains a low amount of coal, a part of the coal will be saved in the calcination process, and the loss is the calcination cost, but no matter how it is calculated, it is much more cost-effective than buying fly ash from the power plant.

Thinking of this, Fang Dajun showed a wicked smile, in the early stage, he would indeed ask various production teams to buy coal, but he would add an add-on, for every ton of coal purchased, he must give half a ton of coal gangue for free, and he also needs to be transported to the cement factory for free.

After selling this half ton of coal gangue as cement, you can earn back the money you made to buy this ton of coal, so repeatedly, don't make too much.

An industrial line was formed in his mind, first he bought coal and came back for crushing, and the high-quality coal was sent to the cement plant, and the slightly worse coal was used to make honeycomb coal, and he could personally make a profit from it, and then use free coal gangue to calcinate the cement mixture, so as to reduce the cost of cement, so that the cement factory can also make money.

He has 40 percent of the shares of the honeycomb coal plant and 50 percent of the cement plant, in fact, they are almost the same, except for a price difference between the two factories, and the rest is not to be considered, because his dividends on both sides are about the same.

――――――

Facing the rising sun, the two rushed to the passenger station, Fang Dajun gave up the self-driving tour, and felt that it was more convenient to take the car, and the bicycle was left in the guest house.

Of course, there is passenger circulation between counties, because it is the starting station, so there is no need to worry about the seats, besides, Li Yulan has not taken a bus, and she is also very curious.

The ticket is naturally to be bought, but it is a handwritten ticket, and the next car has to wait for more than half an hour, just right, the gift he prepared can also be taken out, I hope it will be lethal enough.

"Magnolia, go to the front and sit down!"

"Yes!" Li Yulan was a little nervous, and the environment in the station made her a little uncomfortable.

After a while, the two of them found a long bench in the corner and sat down, there was no specific waiting room, everyone gathered in the hall to wait, shuttling through many hawkers carrying baskets to sell, and it was also lively.

"Magnolia, look what's in this box." Fang Dajun was full of smiles, for this thing, he didn't spend much effort in the morning.

"I can't guess." Li Yulan replied honestly, when she set off from the guest house, she saw that the army was holding a box in her hand, cautiously, for fear of breaking it, although she was curious, she didn't want to ask too much.

At this time, the cardboard box of the book was opened, Li Yulan's face was full of surprise, it was actually a cake inside, she had only seen pictures in books before, "Dajun, when did you buy the cake?" ”

"Hehe, when I went out to buy something in the morning, I happened to see a cake shop next to it, so I bought one by the way and tasted it together to see how it tasted." As he spoke, he took out a knife, this cake is actually not big, only more than 20 centimeters in diameter, and the top third is the cream, because he was in a hurry, he bought it in stock, and the cream was only decorated with a few big red flowers, and there was no handwriting.

"How much does this cake cost?" Li Yulan's face was a little hot, she felt that this was specially bought for her by the army.

"It's not expensive, you can eat it with confidence." Without saying much, he picked up the knife and cut it, and his mind suddenly moved, "Yulan, you can also help support." ”

"Yes!" Li Yulan has long been greedy, and the book says that the cake is delicious, especially the cream on it.

Li Yulan put his hands on the bottom of the box, his right hand got the knife, and his left hand inadvertently covered Li Yulan's little hand, the expression on his face remained unchanged, but his heartbeat suddenly accelerated, and he still pretended not to care at all, and cut the cake steadily with his right hand.

And Li Yulan's cheeks were already red, she felt that Dajun's hands were so hot, and the back of her hands was already sweating, but seeing Dajun concentrating on cutting the cake, she couldn't say anything for a while.

"Hehe, alright!" The cake is cut into eight triangles, three of which are topped with large saffron cream. A cream cake of the same size will cost about 30 yuan after 30 years, and a more high-end fruit cake will cost two or three hundred.

He spent seven yuan on this cake in his hand, compared to thirty yuan, it is definitely expensive, but unfortunately Beidou can't afford to support cake consumption at present, otherwise he can open a cake store himself.

He let go of his right hand and continued to pretend that nothing had happened, and happily picked out a cake with flowers, "Magnolia, taste it, don't you like to eat sweet things, this cake must suit your taste." ”

Li Yulan's face was even hotter, and sure enough, the army bought it for her, she couldn't afford this heart, and she didn't know how to repay it.

"What do you think?" Fang Dajun asked suspiciously, according to previous estimates, Li Yulan shouldn't have reacted like this, could it be that the lethality of the cake is not enough?

"It's nothing, I wonder if the cake wasn't eaten on my birthday?" Li Yulan replied sweetly, she has no idea now, and she doesn't dare to think about it, and plans to find Jinchi to give her advice after returning to the commune.

"Hehe, then it should be your birthday last year, by the way, when is your birthday?" He really didn't know about it.

"I'm still early, the twenty-fourth of the winter moon is gone." Li Yulan took the cake and felt that this flower was so beautiful, and she was a little reluctant to eat it.

Fang Dajun urged Li Yulan to bite into the cake, and when he saw that her beautiful eyes were happy to turn into crescent moons, and her red lips were glued with cream, he said happily: "It's delicious!" It's almost the New Year on your birthday. ”

"Well, every year's birthday is celebrated with the New Year. The cake is delicious, the cream is so slippery, thank you, army. Li Yulan looked a little shy, although the army didn't say the price of the cake, but it was definitely not cheap.

"Thank you, this money can be reimbursed anyway, hehe. Well, it tastes really good. Fang Dajun also ate it himself, like a cow chewing peonies, he hadn't eaten cake so seriously for many years, because the previous birthday cakes were wiped on his face, and now that he thinks about it, it's really a waste.

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