Singapore strongly condemns North Korea’s “reckless” missile and nuclear tests, and calls on it to avoid further provocative actions, said Minister for Foreign Affairs Vivian Balakrishnan. Stratstimes.com

A federal oversight panel reports that Los Alamos National Laboratory workers producing a shell for a triggering device for nuclear weapons violated safety rules in August by storing too much material at one location in a facility for plutonium, a highly radioactive material. Newobserver.com

North Korea said on Saturday targeting the U.S. mainland with its rockets was inevitable after “Mr. Evil President” Donald Trump called Pyongyang’s leader “rocket man”, further escalating rhetoric over the North’s nuclear weapons and missile programs. Reuters.com

Iraq asked on Saturday for assistance in building a nuclear power reactor for peaceful purposes, more than 25 years after the destruction of the reactors it had under Saddam Hussein. Reuters.com

 

       I recently wrote about the Soviet Union using a nuclear warhead to extinguish a fire in a natural gas well that had resisted all other attempts to put it out and had been burning for three years. While the U.S. and other nuclear nations considered the civilian use of nuclear warhead for such things as massive earthmoving projects, the Soviet Union was the most active nation in tested such uses. On one occasion, they created an artificial lake with a nuclear explosion.

       The Soviet Union had a program called “Nuclear Explosions for the National Economy” established for the explicit purpose of testing civilian uses for nuclear bombs. The program carried out one hundred and fifty six nuclear tests between 1965 and 1989.

      In 1965, a one hundred and forty kiloton nuclear bomb was detonated five hundred and eighty four feet under the dry bed of the Chagan River at Chagan which is on the edge of the Semipalatinsk Test Site in Kazakhstan. The blast resulted in the formation of a crater that was one thousand three hundred and twelve feet in diameter and three hundred and twenty eight feet deep. There was a “lip” around the crater that varied from sixty five feet to one hundred and twenty five feet high. A channel was cut a nearby river so that it could fill up the crater to create the new reservoir which was named Lake Chagan.

      The purpose of the detonation was to determine whether nuclear explosions would be a good way to create new reservoirs. This test was carried out with the largest bomb ever used in the Nuclear Explosions for the National Economy program and it was the very first test carried out under the program.

        It has been estimated that about one fifth of the radioactive isotopes created by the blast escaped from the underground cavity. Following the blast, radioactive fallout was detected over Japan, twenty five hundred miles to the east of the test site. In 1963, the Soviet Union had signed the Limited Test Ban Treaty (LTBT) which prohibited atmospheric detonations. The U.S. accused the Soviet Union of violating the treaty. The Soviet response was that the test was underground and the amount of radioactive materials released was not significant. Although the treaty did ban any detonations that caused radioactive materials to go beyond the borders of the country conducting the test, the potential violation of the LTBT by the Soviets was eventually dropped.

        While Lake Chagan shows that it is indeed possible to create new artificial lakes with the use of underground nuclear explosions, it is not really practical because the water in Lake Chagan (also known as Atomic Lake) is still radioactive and unsuitable for the use of watering livestock. It would also not be a good idea to use the water for irrigation. Today, the water of Lake Chagan is about one hundred times as radioactive as the level considered safe for drinking water. Three hundred to five hundred feet from the reservoir, the level of radioactivity drops back to the normal background level.

Arial shot of Lake Chagan:

 

The 100,000-ton US Navy supercarrier ‘Ronald Reagan’ has conducted drills with Japanese warships south of the Korean Peninsula, Japan’s military said. Pyongyang, meanwhile, has threatened a further “hydrogen bomb test” over the Pacific. rt.com

 Tropical storm Jose has been churning up the waters of Cape Cod Bay and creating operational problems for Pilgrim Nuclear Power Station in the process. Patriotledger.com

Workers are setting the groundwork at Three Mile Island for a maintenance outage this month to replenish Unit 1’s uranium core, an elaborately choreographed event that requires 1,500 contract workers and injects millions of dollars into the local economy. Mcall.com

Following two years of planning, demolition of the West Valley Demonstration Project (WVDP) vitrification facility in New York State began last week. The work is scheduled to be completed in eight months. World-nuclear-news.org

Part 2 of 2 Parts (Please read Part 1 first)

       The second main type of Generation IV reactors is referred to as fast reactors. In a fast reactor, the fast neutrons generated by the fission reaction are directly used without a moderator to slow them down. These reactors can burn or subject to fission all the actinides (which includes uranium, plutonium and fifteen other highly radioactive heavy metals). Since it is the actinides that make nuclear waste so dangerous, burning all the actinides in the fuel can significantly reduce the bulk of nuclear waste and the longevity of its danger. On the other hand, these reactors can be configured to generate more actinides than they burn and thus they can actually “breed” fuel.

       The Gas-cooled fast reactor (GFR) is helium cooled and can generate heat at the temperature of eight hundred and fifty degrees Centigrade. It is considered to be an evolution of the VHTR discussed above under thermal reactors. Special fuels are being considered and developed to withstand the high temperatures and to retain the actinides in the original fuel and actinides generated by the fission reaction. Physically, the core configurations will be pin-based, plate-based or prismatic blocks. Construction of a gas-cooled fast reactor will begin in 2018 by the European Sustainable Nuclear Industrial Initiative (ESNII).

        The Sodium-cooled fast reactor (SFR) is a sodium molten-salt cooled reactor utilizing fast neutrons. A core with no moderators burns a metallic alloy of uranium and plutonium or any transuranic isotopes. Spent nuclear fuel from LWRs can be used as a fuel. When a SFR overheats, the core expands and the chain reaction slows down so it is what is called “passively safe. One of the main problems with this type of reactor is the fact that the sodium which is cooling the core will react explosively if it comes into contact with water. The liquid metal coolant does allow the reactor to operate at atmospheric pressure which is a plus. India has been researching this type of reactor since the 1980s. They are building a prototype of a commercial reactor and are planning on building six commercial reactors in the near future. The ESNII will make a final decision on the construction of an experimental SFR in 2019. China purchased an SFR from Russia that went operational in 2014.

       The Lead-cooled fast reactor (LFR) is a fast neutron reactor cooled by liquid lead or lead/bismuth eutectic in a closed fuel cycle. The fuel is metal or nitride-based composed of fertile uranium and transuranics. Natural convection cools the reactor core and they could be designed to generate heat at a temperature of eight hundred degrees Centigrade for hydrogen production. They can be used in batteries of small reactors or as one large reactor. The ESNII is funding a lead-cooled fast reactor which will be built in Belgium. Russia is building two LFRs, one of which has been redesigned to be proliferation resistant.

        The major benefits of the Generation IV reactors are expected to be reduction of the life span and volume of nuclear waste, up to three times more energy from the same amount of fuel, a broader range of possible fuels, the ability to consume spent nuclear fuel from other reactors, and greater safety.

         Some of the disadvantages of Generation IV reactors include danger of fire and explosions if sodium coolant contacts water. Lead is not dangerous in contact with water but when compared to sodium, it has higher viscosity, higher density, less heat capacity and more radioactive neutron activation products.

Pool design Sodium-Cooled Fast Reactor:

 

Member states of the International Atomic Energy Agency (IAEA) have celebrated the 20th anniversary of the adoption of the Joint Convention on Spent Fuel and Radioactive Waste Safety. The convention has contributed to a significant level of safety in the management of used fuel and radioactive waste, said IAEA deputy director general Juan Carlos Lentijo. World-nuclear-news.org

SCANA Corporation said Thursday that it had been issued a subpoena from the U.S. Attorney’s Office in South Carolina for documents related to the canceled expansion project at the V.C. Summer Nuclear Station. Nuclearstreet.com

U.S. President Donald Trump ordered new sanctions on Thursday that open the door wider to blacklisting people and entities doing business with North Korea, including its shipping and trade networks, further tightening the screws on Pyongyang’s nuclear and missile programs. Aol.com

A 6.1 magnitude earthquake hit the northeast coast of Japan, just 200 miles east of the damaged Fukushima nuclear power plant. Newsweek.com

Part 1 of 2 Parts

       I have made reference to “generations” of nuclear power reactors in previous posts. Currently, most of the reactors generating electricity are considered to be Generation II. The old Generation I reactors have been retired. There are about a dozen Generation III reactors in commercial operation out of about four hundred reactors across the globe.

       Generation IV refers to a set of nuclear reactor designs that are being researched for possible commercial application in power generation. The Generation IV International Forum is leading this research. The designs are in different stages of technological readiness from needing a demonstration of basic principle to demonstrating economical competitiveness. The new designs are dedicated to such goals as improving safety, sustainability, efficiency and cost. Most of these new designs are not expected to be available for construction until 2020 at the earliest and 2030 at the latest. There are theoretical designs for Generation V reactors but they have received little funding to date.

      Broadly speaking, the Generation IV designs fall into two main categories. The first category is called thermal reactors. This term refers to the use of what are called slow or thermal neutrons. A moderator is used to slow down the neutrons that are emitted by the fusion reaction. This makes them more likely to be captured by atoms in the fuel.

        The Very-High-Temperature Reactor (VHTR) uses a core moderated by graphite with a once-through uranium fuel cycle. Helium or a molten salt are used for coolant. This reactor can produce heat in the range of a thousand degrees Centigrade. Physically, the reactor can be a prismatic-block or pebble bed reactor design. The high temperature heat that a VHTR can produce is being considered for use as an industrial heat source for production of hydrogen as well as for generating electricity. The Chinese are working on a series of experimental VHTR reactors. The U.S. hopes to complete a prototype VHTR by 2021 at the Idaho National Laboratory.

        The Molten-salt Reactor (MSR) utilizes a molten salt mixture as the coolant and may mix the fuel into the molten salt. There have been many designs and a few test versions of such reactors built. The most popular approach dissolved uranium tetrafluoride in molten fluoride salt. Graphite is used as a moderator in the core. Using molten salt for cooling is a low pressure, high temperature method of cooling. A number of different cooling schemes and fuel types are being explored. One possible use of an MSR would be to burn nuclear waste from other reactors to reduce the volume of waste.

       The Supercritical-water-cooled Reactor (SCWR) is a light water reactor operating at higher temperature and pressures than current light water reactors (LWR). The neutrons in an SCWR are faster than thermal neutrons and are referred to as epithermal neutrons. Supercritical water is the working coolant with a once-through heat exchange cycle. This type of reactor can operate at higher temperatures and pressures than pressurized water reactors and boiling water reactors. SCWR have a high thermal efficiency which is about fifty percent better than current LWRs. Because of the supercritical water, the design of the plant is much simpler than LWR plant designs. SCWRs have benefits but they also have technical difficulties in that all the piping and other machinery must be designed to handle much higher temperatures and pressures than current power reactors.

Please Read Part 2

The world’s first legally-binding treaty prohibiting nuclear weapons opened for signature today at United Nations Headquarters in New York at a ceremony at which speakers from international organizations, governments and civil society hailed this milestone in achieving a world free of such arsenals as well as the work that remains to be done. Un.org

North Korea has this year repeatedly provoked worldwide outrage with a series of nuclear tests and missile launches, prompting condemnation and threats from despot Kim Jong-un’s Western rivals. And it has now been revealed the campaign of terror is partly thanks to China, who have been supplying North Korea with a key ingredient. Express.co.uk

Russia and Paraguay have signed an agreement on cooperation for peaceful use of nuclear power. The document was signed yesterday, in Vienna, during the 61st International Atomic Energy Agency General Conference, by Alexey Likhachov, director-general of Rosatom, and César Cardozo Román, minister and executive secretary of the National Radiological and Nuclear Control Agency (Autoridad Reguladora Radiológica y Nuclear, ARRN) of Paraguay. World-nuclear-news.org

The head of Russian nuclear power giant Rosatom Alexei Likhachev said Tuesday that construction work had begun at Akkuyu in Turkey, a southern city on the Mediterranean Sea that will house the country’s first nuclear power plant. Nuclearstreet.com