[imText1]On May 11, North Korea officially announced that it had finished taking out the fuel rods from the 5MW reactor at the Yongbyon site which had been shutdown.
Let’s look into technical details of the nuclear reprocessing issue that takes after taking out the spent nuclear fuel rods, which is a new variable added to the North Korean nuclear problem.
Spent Fuel Rods Reprocessing to be Completed in August
April 7, North Korea announced shutdown of the Yongbyon reactor. Its shutdown means possibility to take out the spent fuel rods. The reactors function with the nuclear fuel rods.
The spent fuel rods are as logs for fire. Just as the ash left as remnants after the fire, after the nuclear fuel rods emit energy the spend fuel rods are left.. The problem is that it takes about a month to cool down the spend fuel rods, in order to decrease radiation before it is possible to extract plutonium.
If we calculate the dates, since it has announced the shutdown of the reactor in the mid April, the fastest North Korean can start taking out the nuclear fuel rods is mid May. Many experts believe it may take North Korea more than two months to take out all the fuel rods with the current technology North Korea has. However, North Korea has already announced that it has completed pulling out all the spent fuel rods. Although it is highly doubtful, some also argue that it is not impossible, if done with excessive labor.
The spent fuel remaining in the rods could be reprocessed to extract plutonium, which can be used for building nuclear weapons
The process of reprocessing is roughly like the following. First, the spend fuel rods must be cooled down in order to decrease radiation, which takes about three months. Then the rods are cut into small pieces of 3cm-4cm. The fuel rods are covered with cladding which needs to be peeled off by diluting in nitrate. When the fuel rods are soaked in the nitrate, the spend fuel is diluted but the cladding does not, so the cladding could be removed from the fuel.
The next step is to separate the spent fuel components diluted in nitrate. In the process of separation, the diluted fuel divides into uranium and plutonium. Uranium is used recycled for nuclear energy while plutonium is used for building nuclear weapons or for the mixed nuclear energy.
The reason why the world is suspicious about the North Korean nuclear facility being the facility to build nuclear weapons is because North Korea has the facility to reprocess the spent fuel rods. There are some who believe, “reprocess is needed to recycle the spent nuclear fuel” but considering that the bountiful uranium deposit in North Korea and the complicated reprocessing process with high risk of nuclear radiation, such an argument lacks logical rationality. Furthermore, taking into account the serious and long lasting economic crisis which North Korea is facing, it has no reason to conduct such a highly extravagant reprocessing activity if it is for nuclear recycling.
North Korea Possible to Produce 7-8 Nucs After Reprocessing the Spent Fuel Rods
Taking out the spent fuel rods does not mean nuclear reprocessing. Although it varies on the types of nuclear reactors, but generally, the rods must be replaced in ever two to three years. Since North Korea started to operate the Yongbyon 5MW reactor the day after it pulled out of the NPT, January 10, 2003, it is about time it changed the rods.
For this reason some government officials argue that the shutdown of the Yongbyon reactor does not mean nuclear reprocessing and they are only threats to stimulate the negotiations. However, there is no reason for North Korea to suddenly shutdown a well-functioning nuclear reactor. Furthermore, it seems least likely for North Korea to leave the reactor for observation or to take out the fuel rods and bury them underground.
The reprocessing facility, 120m in width, 80m in length, and height of a six floor building in size is probably not built for nothing.
In the announcement two days ago, North Korean Ministry of Foreign Affairs strongly implied that the North Korea will reprocess the spent fuel rods by stating, “We, accordingly, will lay our basis (importance) on developing nuclear powered independent industries and in increasing the nuclear weapons for the defense purpose.”
IAEA and other state intelligence agencies predict that before the 1994 Agreed Framework, North Korea had already produced 10kg of plutonium already. From the 8,000 spent fuel rods of which North Korea proclaimed to have been taken out in 2003, it would have already extracted 25kg to 30kg of plutonium.
From the 8,000 spent fuel rods recently taken, North Korean will be able to gain another 10kg to 12kg of plutonium after the reprocessing. That is enough to make two nuclear weapons. In the end, North Korea will possess enough of plutonium to build seven to eight nuclear weapons.