The most obvious advantage of fly ash cement is that it has good crack resistance and can withstand the erosion of time. The strength in the later stage will exceed that of silicate cement. Currently, the buildings in small places are mainly prefabricated boards. This type of cement is just right for it. He can even set up a prefabricated board processing factory by himself.

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

It is a waste stone that is associated with coal, with a low carbon content of only 20%-30%. It cannot be burned in an ordinary furnace and its texture is harder than coal. As long as coal is digging, a large amount of useless coal gangue has to be cleaned up.

It is also called "coal sand layer" locally because coal gangue will weather and crush after being exposed to long-term sun and rain. In addition, coal gangue will disintegrate after absorbing water, which can easily produce dust, and even spontaneous combustion, discharge waste gas, and pollute the environment.

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

Although there are no open-pit coal mines in the Beidou area, on some rocky levels, coal gangue layers of different thicknesses will be exposed to the air, and will weather into sand over 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 the process only briefly mentioned using coal gangue instead of fly ash to process cement.

Fly ash and granulated blast furnace slag were originally purchased from outside. There is a steel plant in the county, so there will be iron slag, which is cheap and convenient to purchase. Coal powder is fine ash caught from the flue gas after coal combustion, and is the main solid waste discharged from coal-fired power plants. Coal power generation is still the mainstream.

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

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

However, to make coal gangue live, calcination also requires. However, because coal gangue itself contains low amounts of coal, it will save part of the coal during the calcination process. The cost of calcination is lost. However, no matter how you calculate it, it is much more cost-effective than buying fly ash from a power plant.

Thinking about this, Fang Dajun showed a bad smile. In the early stage, he did ask various production teams to buy coal, but he would add an additional item. For every ton of coal purchase, he had to give away half a ton of coal for free, and he also needed to transport it to the cement factory for free.

Just selling this half ton of coal gangue as cement can make the money you bought this ton of coal back. If you repeat this, don’t earn too much.

An industrial line formed in my mind. First, I bought coal and crushed it. The high-quality coal was sent to the cement factory. The slightly worse ones were used to make honeycomb coal. He could make a fortune from it. Then he used free coal gangue to calcin the cement mixture to compress the cost of cement and allow the cement factory to make money.

He has 40% of the shares of the Fengwo Coal Factory and 50% of the cement factory, which is actually almost the same. Except for the price difference between the two factories, there is no need to worry about the rest, because his dividends on both sides are almost the same.

—————

Facing the rising Chaoyang, the two arrived at the passenger station. Fang Dajun gave up his self-driving tour and thought it was more convenient to take a car, so he left his bicycle in the guesthouse.

Of course, there is passenger traffic between counties. Because it is the starting point, there is no need to worry about seating. Besides, Li Yulan hasn't taken the bus yet, so she is curious.

Of course, I have to buy a ticket, but it is just a handwritten note. I have to wait for more than half an hour for the next car. Just so I can take out the gift he prepared, hoping it will have enough lethality.

"Magnolia, go to the front to have a seat!"

"Yeah!" 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 to sit down. There was no specific waiting room. Everyone gathered in the hall to wait, and there were many hawkers carrying baskets to hawk in, and it was also lively.

"Magnolia, look at what's in this box." Fang Dajun smiled. He spent a lot of effort on this thing in the morning.

"I can't guess." Li Yulan replied honestly. When she left the guesthouse, she saw Dajun holding a box in her hand, cautious, afraid that it would be broken. Although she was curious, she didn't ask much.

At this time, the paper box as big as a book was opened, and Li Yulan's face was filled with surprise. There was actually a cake inside. She had only seen pictures in books before, "Dajun, when did you buy the cake?"

"Haha, when I went out to buy something in the morning, I happened to see a cake shop next to me, so I bought one and try it together to see how it tastes." As he said that, he took out a knife. The cake was actually not big, with a diameter of only more than 20 centimeters, and one-third of the top was cream. Because I was in a hurry, I bought it in stock, and the cream was only decorated with a few big red flowers, and no trace was left.

"How much does this cake cost?" Li Yulan's face felt a little hot. She felt that it was bought by Dajun for her purpose.

"You can eat it for the inexpensive things." Without further ado, I picked up the knife and started cutting it. My mind suddenly moved, "Magnolia, please help me."

"Yeah!" Li Yulan had long been greedy. The book said that the cake was delicious, especially the cream on it.

Li Yulan held the bottom of the box with both hands, and took the knife in his right hand, and inadvertently covered Li Yulan's little hand with his left hand. His expression remained unchanged, but his heartbeat suddenly accelerated. He still had to pretend not to care at all, and his right hand steadily cut the cake.

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

"Haha, that's OK!" The cake was cut into eight triangles, with three petals containing large saffron cream on it. A cream cake of the same size costs about 30 yuan in thirty years, and a more high-end fruit cake costs two or three hundred yuan.

He spent seven yuan on this cake in his hand, which is definitely expensive compared to thirty yuan. Unfortunately, Beidou can't afford to spend cakes at present, otherwise he could open a cake shop himself.

The right hand loosened, and continued to pretend that nothing happened. He happily picked out a flower-like cake, "Magnolia, try it quickly, don't you like to eat sweet things? This cake must be as good as your taste."

Li Yulan's face became even hotter. Sure enough, Dajun bought it for her on purpose. She couldn't bear this feeling, and she didn't know how to repay her.

"What are you thinking?" Fang Dajun asked in confusion. According to previous estimates, Li Yulan shouldn't have reacted like this. Could it be that the cake's lethality is not enough?

"It's nothing. I'm wondering if the cake was not eaten on my birthday?" Li Yulan replied sweetly. She had no idea now and didn't dare to think too much. She planned to ask Jin Chi to give her advice after returning to the commune.

"Haha, then I'll give you a birthday from last year. By the way, when did your birthday?" He really didn't know about this.

"I'm still early, I'm going to go for the 24th day of the winter moon." Li Yulan took the cake and thought the flower was so beautiful that she couldn't bear to sip.

Fang Dajun urged Li Yulan to bite the cake. Seeing her beautiful eyes happy with crescent moons and her red lips, she said happily: "It's delicious! It's almost the New Year on your birthday."

"Well, I celebrate the New Year's birthday every year. The cake is so delicious, the cream is so smooth, Dajun, thank you." Li Yulan seemed a little shy. Although Dajun didn't say the price of the cake, it was definitely not cheap.

"What are you thanking? Anyway, this money can be reimbursed, haha. Well, it tastes really good." Fang Dajun ate it himself, like a beef chewing peony. He hadn't eaten the cake so seriously for many years, because the birthday cakes used to be applied to his face. Now, it's a waste.
Chapter completed!