Name: 【地層処分の科學】1-1. 核分裂生成物是什麼？ (【地層処分の科学】1-1. 核分裂生成物とは)
Uploaded: 2026-01-02T11:34:23.000Z
Duration: 14 min 45 s

I am professor emerit in EMT Atlantic in France.

我是法國 EMT Atlantic 的榮譽教授。

And I have worked since about 40 years in the area of nuclear waste and in particular in nuclear waste borosilicate glass, where I made also my PhD in the university or Free University of Berlin.

我大約在核廢料領域工作了 40 年，特別是核廢料硼矽酸鹽玻璃，我還在柏林自由大學取得了博士學位。

So my talk is about nuclear waste immobilization in both silicate glass.

我的演講是關於硼矽酸鹽玻璃中的核廢料固定化。

Nuclear waste can also is radioactive waste.

And I would just first explain a little bit where this nuclear waste comes from.

我會先稍微解釋一下這些核廢料的來源。

So we have a nuclear fission reactor which produces a electricity by using nuclear fuel.

我們有一個核分裂反應爐，它透過使用核燃料來產生電力。

And when put this into a nuclear reactor, the nuclear fission is ongoing.

當把它們放進核反應爐時，核分裂就會持續進行。

Here is the reactions which occur and you fabricate fission products.

這裡就是發生的反應，你會製造出裂變產物。

Here you see, for example, you start with uranium and then by neutrons you split the uranium and you produce two fission products and you produce lots of energy.

你可以看到，例如，你從鈾開始，然後透過中子分裂鈾，產生兩種裂變產物，並產生大量能量。

And neutrons with very high energy, which you can then use to transform to electricity.

以及高能量的中子，這些中子之後可以用來轉化成電力。

然後裂變產物就變成了廢棄物。

You need to put them in a stable structure, since they are rather dangerous because.

你需要將它們放入穩定結構中，因為它們相當危險。

Because they have high radiation products, as you can see here.

因為它們具有高輻射產物，就像你這裡看到的。

Lots of radiation emitted by the fission products.

裂變產物會釋放出大量的輻射。

So nuclear fission produces fission products.

As I said, fission products are dangerous because of their high radioactivity.

就像我說的，裂變產物因為高放射性，所以很危險。

Fission products are largely without use.

Long term could be hundreds of thousands of years until they decay to inoffensive levels.

長期可能要幾十萬年，直到它們衰變成無害的程度。

And there is always a risk of dispersion of this fission products somehow.

而且總是有可能以某種方式散播這些裂變產物。

And so we need to isolate them somehow, forever, whatever means this.

所以我們需要用任何方法，永遠地將它們隔離起來。

But a very, very long periods of time, hundreds of thousands years, unprecedented somehow in human history to isolate waste or isolate anything or produce anything which would last for such long time period.

但這需要非常非常長的時間，幾十萬年，這在人類歷史上是前所未有的，要隔離廢棄物或任何東西，或是產生任何能持續這麼長時間的東西。

Nuclear fission products are not only toxic and in this way dangerous for human being.

核分裂產物不僅有毒，對人類來說也很危險。

There's also decay heat associated to this.

That means the radioactive decay produces heat and also a high dose rate.

這意味著放射性衰變會產生熱能，同時也產生高劑量率。

You see here in this case, the dose rate as a function of time for about 100 years.

你在這裡可以看到，這是大約 100 年的劑量率隨時間的變化。

And just to recall that the dose, this is a dose at 1 meter but 1 millisievert.

順帶一提，這個劑量，這是 1 公尺處的劑量，但單位是毫西弗。

So it's about here at that level per year is the threshold which human beings are allowed in our society to be exposed to.

大約在這個水準，每年 1 毫西弗，是我們社會允許人類暴露的劑量上限。

Now Here we have 1 millisievert, we have 1 sievert which is thousand times higher.

現在這裡我們有 1 毫西弗，我們有 1 西弗，是它的千倍。

而且不是每年的，而是每小時的。

So these dose rates are extremely much larger than anything the human being can extend, can accept without health problems.

所以這些劑量率遠遠超過人類能夠承受、不會產生健康問題的任何水準。

And I think here the lethal dose is about 4 sv.

而且我認為這裡的致死劑量大約是 4 西弗。

And so the little dose coming from the nuclear fuel, you get maybe in an hour or so of exposure or even less.

所以來自核燃料的微小劑量，你暴露一小時左右或更短時間就會得到。

So that means very, very important to isolate this nuclear fuel from human beings and from excess, which is not planned, and

所以這意味著，將核燃料與人類以及非預期的暴露隔離開來非常非常重要，

So for doing so, the heat which is produced by the waste, but

所以為了做到這一點，我們需要將廢棄物產生的熱能，

also the radioactivity, we need to cool this in the reactor pools for some years.

以及放射性，在反應爐水池中冷卻數年。

And depending what to do later on with this nuclear fuel, this can be directly stored.

而且取決於之後對這些核燃料的處理方式，可以直接儲存。

For example, there's a nuclear fuel rods which you see here from fuel assemblies compared to the human being, which is here at the size just for size comparison, you see that this is rather huge canister or container for dry storage.

例如，你看到的這些核燃料棒來自燃料組件，與人類相比，這裡只是為了尺寸比較，你看到的是一個相當大的乾式儲存罐或容器。

And you can have spent nuclear fuel at the bottom there.

然後你可以在那裡看到底部的乏核燃料。

And you can see over maybe 4 meters or so of water, you can see down the waste.

你可以看到大約四公尺左右的水，你可以看到裡面的廢棄物。

Nuclear fuel is essentially uranium dioxide with lots of uranium 235, which is put into the.

核燃料基本上是二氧化鈾，含有大量的鈾 235，然後被放入。

The natural isotope composition of uranium is about 0.7% of uranium 235 and 99, 3% of uranium 238.

鈾的天然同位素組成大約是 0.7% 的鈾 235 和 99.3% 的鈾 238。

Now, for being fissile, and the quantity of uranium 235 has been enriched.

現在，為了具有分裂性，鈾 235 的數量已經濃縮了。

And then neutrons could break the uranium and produce fission products.

然後中子就可以分裂鈾並產生裂變產物。

Some uranium is directly fissile and produce fission products from uranium 235.

有些鈾是直接可分裂的，會從鈾 235 產生裂變產物。

But some uranium is also activating the uranium 235.

That means the neutron is taken up by the uranium 235 to produce uranium 236.

這表示中子被鈾 235 吸收，產生鈾 236。

But most of the uranium 235, which is about 80%, is just cut by the neutron into two parts.

但大部分的鈾 235，大約 80%，只是被中子切成兩半。

And these two fission products then are what we call the waste and which we don't.

而這兩種裂變產物就是我們所說的廢棄物，而我們不需要。

But this reaction where the neutron breaks the uranium 235 produces lots of energy.

但這個中子分裂鈾 235 的反應會產生很多能量。

And this can then be converted to electricity.

然後這些能量就可以轉換成電力。

So this is enriched uranium with uranium 235.

所以這就是濃縮鈾，含有鈾 235。

But we have, of course, also uranium 238.

The uranium 238 can then be transformed by neutrons to plutonium 239.

鈾 238 然後可以被中子轉變成鈽 239。

So we have uranium and we have plutonium.

Now, initially we only had uranium, but by the fission we produced fission products, but

一開始我們只有鈾，但透過裂變，我們產生了裂變產物，但

we produce also by neutron capture, where the neutron is taken up by the uranium, transforms the uranium into plutonium.

我們也會透過中子俘獲產生，中子被鈾吸收，將鈾轉變成鈽。

And the plutonium 239 is then again being exposed by neutrons.

而鈽 239 然後又會被中子照射。

You see here, when some of the plutonium is fissile here, it's 72% or 71%.

你看這裡，有些鈽在這裡是可裂變的，有 72% 或 71%。

And some is then capturing another neutron.

然後有些則會再俘獲一個中子。

And then you go from plutonium 239 to plutonium 40.

然後你就會從鈽 239 變成鈽 40。

So you get a whole series of plutonium isotopes.

所以你會得到一整系列的鈽同位素。

And these actinides are also to a certain degree not useful anymore.

而這些錒系元素在某種程度上也變得沒有用了。

So they become also waste and will be disposed of maybe, or they can be reused, used for making another nuclear fuel.

所以它們也會變成廢棄物，可能會被處理掉，或者可以再利用，用來製造另一種核燃料。

But the fission products are the waste and we need to get rid of.

但是裂變產物是廢棄物，我們需要處理掉。

Either we can dispose the whole thing here, all the products produced by the nuclear reaction.

要嘛我們可以處理掉這裡的全部，所有由核反應產生的產物。

We can dispose all of this as nuclear waste, the whole thing.

我們可以把這整批東西當作核廢料處理掉，全部。

Then we have what we call direct disposal.

接著我們有叫做直接處置的選項。

After four years or so in the nuclear reactor.

在核反應爐裡用了大概四年之後。

We take it out of the nuclear reactor and we put it inside of.

我們會把它從核反應爐裡取出，然後放進。

我們會把它放進一個容器裡進行處置。

Alternatively, we have another option that we only take the fission products out.

或者，我們還有另一個選項，就是我們只取出裂變產物。

But for taking the fission products out, we need to do what we call reprocessing.

但是要取出裂變產物，我們需要做所謂的再處理。

That means we need to desert, dissolve the entire nuclear fuel, plutonium and the fission products and uranium which is still there, and

這表示我們需要溶解整個核燃料、鈽、裂變產物以及仍然在裡面的鈾，然後

dissolve it in nitric acid, very high concentrated nitric acid.

用非常高濃度的硝酸來溶解它。

And then once this is done, once it is dissolved, we need a separate chemical separation plant which will separate the different fractions.

然後一旦完成，一旦溶解了，我們就需要一個獨立的化學分離廠，用來分離不同的部分。