Movie black technology

The fuel element is actually processed nuclear fuel. It looks like a piece of pellets with the same shape, just like an electronic battery commonly used in watches before, but it has to be enlarged.

"Is the expected indicator the same as before?" Chen Shen confirmed it.

Open a projection file over there, and turn to the corresponding page number, "According to current calculations, the ceramic nuclear fuel produced by the new method can achieve the ideal protection rate."

The so-called ceramic nuclear fuel is nuclear fuel used in the form of refractory compounds. At the current general level, after this kind of treatment, 98% of the radioactive fissile substances can be guaranteed not to escape. Only neutrons and gamma rays with strong penetrating ability can radiate out.

However, the system technology is different.

Zeng Le'an circled a number from the document, "According to estimates, the new type of ceramic nuclear fuel should be able to ensure that 99.8% of radioactive fissile substances do not escape, and we will later install the nuclear fuel into the alloy matrix, so that the high melting point of ceramics and The combination of radiation stability and metal's better strength, plasticity and thermal conductivity further increases safety."

"In this way, even if the fuel element cladding ruptures, the outer metal matrix can reduce the leakage of fission products."

When it comes to nuclear-related matters, the first consideration is safety, especially for micro-nuclear reactors.

The specially treated ceramic layer outside the nuclear fuel is the first line of defense, while the second line of defense is the alloy matrix outside the ceramic. In addition to these two lines of defense, there are other lines of defense.

It can be said that nearly one-third of the 16-ton weight of the nuclear reactor is used for leak prevention.

Chen Shen nodded, "Let's produce the fuel elements first, and the design of other plans must be done quickly. We only have nine months."

"Also, is there no problem with the supply of plutonium-239?"

Qi Long, who was in charge of the production process, took the initiative to say: "We are already going through the application process, and it is estimated that we can get a special approval in a few days."

"That's fine."

The nuclear fuel used on the Tibetan antelope is not uranium 235, which most people are most familiar with, but plutonium 239.

This is also a type of nuclear fuel.

If you want to talk about plutonium 239, you have to talk about the element uranium, which is divided into uranium 235 and uranium 238.

However, only uranium 235 can undergo fission reaction between uranium 235 and 238. Uranium 238 can only be regarded as nuclear waste, and in nature, compared with uranium 238, the reserve of uranium 235 is only about 0.7%, and the amount is extremely rare.

Since uranium 235 is rare, relatively, uranium 238 is naturally the most abundant uranium ore in nature.

And plutonium 239 can just be obtained by bombarding uranium 238 with fast neutrons, because uranium 238 will absorb fast neutrons in a certain proportion, thus turning into plutonium 239, which is equivalent to a process of turning waste into treasure. The waste is transformed into usable nuclear fuel.

Fast neutrons are free neutrons produced in nuclear fission reactions. Generally speaking, as long as a small amount of uranium 235 or plutonium 239 is used to build a reactor, and then a circle of uranium 238 is placed outside the nuclear fuel, you can wait for the mushrooms to grow. After a period of time, when you open the planter, you will find that the uranium 238 inside has grown into plutonium 239.

And the amount of plutonium 239 produced is more than the nuclear fuel used in the reactor, which is still a sure profit business...

This is much easier than using thousands of centrifuges to extract uranium-235 from uranium ore. That method can only be a few kilograms or a dozen kilograms a year, whether it is used to make mushroom bombs or nuclear power plants. None of them are enough.

Moreover, less centrifuges are used in this way, and less electricity is naturally used, and it is more environmentally friendly. Mother Earth also showed a gratified smile.

Therefore, the first mushroom bombs made by many countries that want to quickly enter the mushroom growing club and make a fortune as soon as possible are basically plutonium bombs.

The current typical example is the neighbor who is preparing to go to the sun next to him, and there used to be the early fat mushroom bombs on the opposite side, all of which are plutonium bombs.

The nuclear reactor of Tibetan Antelope is also designed based on this principle of uranium into plutonium, and its full name should be called [fast neutron breeder nuclear reactor].

This kind of reactor is not the first of its kind in the system, it has been thought of in the last century.

Moreover, the system has not made much innovation in structure. Compared with the general nuclear reactor, which is composed of nuclear fuel, moderator, control rods, coolant, and reaction layer, the nuclear reactor of the system only lacks a part of the moderator.

Because the role of the moderator is to slow down the speed of neutrons produced in the fission reaction, so that they change from fast neutrons to slow neutrons, so that uranium 235 can produce fission reactions. The "heavy water" that the public often hears is a kind of moderator, which can reduce the speed of fast neutrons from 14,000 kilometers per second to several kilometers per second and become slow neutrons.

Reactors fueled with plutonium do not need moderators because only fast neutrons can cause plutonium to undergo a fission reaction.

Except for the speed reducer, the design ideas of other parts are not much different from the current one. The only difference is the progress of materials and technology.

One of the biggest breakthroughs is the systematic breakthrough in the method of plutonium utilization in the reactor.

Generally, the plutonium-239 produced in fast breeder reactors cannot be used directly. It needs to be taken out for secondary treatment, and the plutonium extracted from it can be used as fuel again.

According to the technology of the system, the uranium 238 used as the breeding layer can be specially treated. After the uranium 238 after this treatment is converted into plutonium 239, it can be sent into the reactor by mechanical means without secondary removal and treatment. used as nuclear fuel.

This is good for reducing the size of the reactor.

Because at present, in the case of neutron-reflecting materials, the critical mass for fission of spherical plutonium is ten kilograms, that is to say, as long as it is made into a spherical shape, only ten kilograms are needed to cause fission of plutonium-239 and then a chain reaction.

This critical mass is less than half of the fifteen kilograms of uranium-235.

In addition, the neutron reflector of the Tibetan Antelope is specially made, and its efficiency is higher than the current one. It can reflect more fast neutrons, making nuclear fuel more prone to fission reactions.

Therefore, even if the plutonium fuel is not made into a sphere, the critical mass can be reduced to ten kilograms. In this way, a circle of uranium 238 is arranged on the periphery, and when they are converted into plutonium 239, the maximum energy can be released with the lightest fuel weight.

After using this technology, coupled with advances in materials, the core part of the nuclear reactor was designed as a cylinder, only 85 centimeters high and only three meters in diameter, which could perfectly fit into the top of the Tibetan Antelope.

"What about control rod design now?"

The problem of the nuclear fuel part was solved, and Chen Shen turned to other parts.

Zeng Le'an quickly flipped the projected data on the screen to the other side, "Now the preliminary design of the control rod has been completed."

I found that I really can't write fast... three to four changes a day may really be my limit speed...