Category Archives: Chemical engineering

Converting Carbon Dioxide into Useful Products

In my 19 December 2016 post, “What to do with Carbon Dioxide,” I provided an overview of the following three technologies being developed for underground storage (sequestration) or industrial utilization of carbon dioxide:

  • Store in basalt formations by making carbonate rock
  • Store in fractures in deep crystalline rock
  • Make ethanol

You can read this post here:

In the past two years, significant progress has been made in the development of processes to convert gaseous carbon dioxide waste streams into useful products.   This post is intended to highlight some of the advances being made and provide links to additional current sources of information on this subject.

1. Carbon XPrize:  Transforming carbon dioxide into valuable products

The NRG / Cosia XPrize is a $20 million global competition to develop breakthrough technologies that will convert carbon dioxide emissions from large point sources like power plants and industrial facilities into valuable products such as building materials, alternative fuels and other items used every day.  You’ll find details on this competition on the XPrize website at the following link:

As shown in the following timeline from the above website, this competition started in September 2015.

Carbon XPrize schedule

In April 2018, the following ten international teams were selected as finalists:

  • Four teams from Canada:  Carbicrete, Carbon Upcycling Technologies, CarbonCure and CERT
  • Three teams from USA:  C2CNT, Carbon Upcycling UCLA and Newlight
  • One team from UK:  Carbon Capture Machine
  • One team from India:  Breathe
  • One team from China:  C4X

The processes being developed by these teams will produce a range of valuable products:

You can read more about each of the competing teams and their intended products in the XPrize finalist selection report here:

The competition is now in the testing and certification phase.  Each team is expected to scale up their pilot systems by a factor of 10 for the operational phase, which starts in June 2019 at the Wyoming Integrated Test Center and the Alberta (Canada) Carbon Conversion Technology Center.  

The teams will be judged by the amount of carbon dioxide converted into usable products and the value of those products.  We’ll have to wait until the spring of 2020 for the results of this competition.

2. World’s largest post-combustion carbon capture project

Post-combustion carbon capture refers to capturing carbon dioxide from flue gas after a fossil fuel (e.g., coal, natural gas or oil) has been burned and before the flue gas is exhausted to the atmosphere.  You’ll find a 2016 review of post-combustion carbon capture technologies in the paper by Y. Wang, et al., “A Review of Post-combustion Carbon Dioxide  Capture Technologies from Coal-fired Power Plants,” which is available on the ScienceDirect website here:

In January 2017, NRG Energy reported the completion of the Petra Nova post-combustion carbon capture project, which is designed to remove 90% of the carbon dioxide from a 240 MW “slipstream” of flue gas at the existing W. A. Parish generating plant Unit 8.  The “slipstream” represents 40% of the total flue gas flow from the coal-fired 610 MW Unit 8.  To date, this is the largest post-combustion carbon capture project in the world.  Approximately 1.4 million metric tons of carbon dioxide will be captured annually using a process jointly developed by Mitsubishi Heavy Industries, Ltd. (MHI) and the Kansai Electric Power Co.  The US Department of Energy (DOE) supported this project with a $190 million grant.

The DOE reported: “The project will utilize a proven carbon capture process, which uses a high-performance solvent for carbon dioxide absorption and desorption. The captured carbon dioxide will be compressed and transported through an 80 mile pipeline to an operating oil field where it will be utilized for enhanced oil recovery (EOR) and ultimately sequestered (in the ground).”

Process flow diagram for Petra Nova carbon dioxide capture and processing.  
Source: National Energy Technology Laboratory
The Petra Nova large-scale carbon dioxide scrubber.  
Source: Business Wire

You’ll find more information on the Petra Nova project at the following links:


3. Pilot-scale projects to convert carbon dioxide to synthetic fuel

Thyssenkrupp pilot project for conversion of steel mill gases into methanol

In September 2018, Thyssenkrupp reported that it had “commenced production of the synthetic fuel methanol from steel mill gases. It is the first time anywhere in the world that gases from steel production – including the carbon dioxide they contain – are being converted into chemicals. The start-up was part of the Carbon2Chem project, which is being funded to the tune of around 60 million euros by Germany’s Federal Ministry of Education and Research (BMBF)……..‘Today the Carbon2Chem concept is proving its value in practice,’ said Guido Kerkhoff, CEO of Thyssenkrupp. ‘Our vision of virtually carbon dioxide-free steel production is taking shape.’”

You can read the Thyssenkrupp press release here:

Berkeley Laboratory developing a copper catalyst that yields high efficiency carbon dioxide-to-fuels conversion

The DOE Lawrence Berkeley National Laboratory (Berkeley Lab) has been engaged for many years in creating clean chemical manufacturing processes that can put carbon dioxide to good use.  In September 2017, Berkeley Lab announced that its scientists has developed a new electrocatalyst comprised of copper nanoparticles that can directly convert carbon dioxide into multi-carbon fuels and alcohols (e.g., ethylene, ethanol, and propanol) using record-low inputs of energy.  For more information, see the Global Energy World article here:

4. Pilot-scale “Negative Emissions Technology” plants

The term negative emissions technology (NET) refers to an industrial processes designed to remove and sequester carbon dioxide directly from the ambient atmosphere rather than from a large point source of carbon dioxide generation (e.g. the flue gas from a fossil-fueled power generating station or a steel mill).  Think of a NET facility as a carbon dioxide removal “factory” that can be sited independently from the sources of carbon dioxide generation.

The Swiss firm Climeworks is in the business of developing carbon dioxide removal factories using the following process:

“Our plants capture atmospheric carbon with a filter. Air is drawn into the plant and the carbon dioxide within the air is chemically bound to the filter.  Once the filter is saturated with carbon dioxide it is heated (using mainly low-grade heat as an energy source) to around 100 °C (212 °F). The carbon dioxide is then released from the filter and collected as concentrated carbon dioxide gas to supply to customers or for negative emissions technologies.  Carbon dioxide-free air is released back into the atmosphere. This continuous cycle is then ready to start again. The filter is reused many times and lasts for several thousand cycles.”

This process is shown in the following Climeworks diagram:

Source: Climeworks

You’ll find more information on Climeworks on their website here:

Climeworks NET in Iceland

In 2017, Climeworks began operation in Iceland of their first pilot facility to remove carbon dioxide from ambient air and produce concentrated carbon dioxide that is injected into underground basaltic rock formations, where the carbon dioxide gets converted into carbonite minerals in a relatively short period of time (1 – 2 years) and remains fixed in the rock.  Climeworks uses waste heat from a nearby geothermal generating plant to help run their carbon capture system.  This process is shown in the following diagram.

Source: Climeworks

This small-scale pilot facility is capable of removing only about 50 tons of carbon dioxide from the atmosphere per year, but can be scaled up to a much larger facility.  You’ll find more information on this Climeworks project here:

Climeworks NET in Italy

In October 2018, Climeworks began operation in Italy of another pilot-scale NET facility designed to remove carbon dioxide from the atmosphere.  This facility is designed to remove 150 tons of carbon dioxide from the atmosphere per year and produce a natural gas product stream from the atmospheric carbon dioxide, water, and electricity.  You’ll find more information on this Climeworks project here:

5. Consensus reports on waste stream utilization and negative emissions technologies (NETs)

The National Academies Press (NAP) recently published a consensus study report entitled, “Gaseous Carbon Waste Streams Utilization, Status and Research Needs,”  which examines the following processes:

  • Mineral carbonation to produce construction material
  • Chemical conversion of carbon dioxide into commodity chemicals and fuels
  • Biological conversion (photosynthetic & non-photosynthetic) of carbon dioxide into commodity chemicals and fuels
  • Methane and biogas waste utilization

The authors note that, “previous assessments have concluded that …… > 10 percent of the current global anthropogenic carbon dioxide emissions….could feasibly be utilized within the next several decades if certain technological advancements are achieved and if economic and political drivers are in place.”

Source: National Academies Press

You can download a free pdf copy of this report here:

Also on the NAP website is a prepublication report entitled, “Negative Emissions Technologies and Reliable Sequestration.” The authors note that NETs “can have the same impact on the atmosphere and climate as preventing an equal amount of carbon dioxide from being emitted from a point source.”

Source: National Academies Press

You can download a free pdf copy of this report here:

In this report, the authors note that recent analyses found that deploying NETs may be less expensive and less disruptive than reducing some emissions at the source, such as a substantial portion of agricultural and land-use emissions and some transportation emissions. “ For example, NAPs could be a means for mitigating the methane generated from enteric fermentation in the digestive systems of very large numbers of ruminant animals (e.g., in the U.S., primarily beef and dairy cattle).  For more information on this particular matter, please refer to my 31 December 2016 post, “Cow Farts Could be Subject to Regulation Under a New California Law,” which you’ll find here:

75th Anniversary of the US Nuclear Weapons Complex

1.  Background

On 19 January 1942, US President Franklin D. Roosevelt approved the production of an atomic bomb.  At that time, most of the technology for producing an atomic bomb still needed to be developed and the US had very little infrastructure in place to support that work.

The Manhattan Engineer District (MED, aka the “Manhattan Project”) was responsible for the research, design, construction and operation of the early US nuclear weapons complex and for delivering atomic bombs to the US Army during World War II (WW II) and in the immediate post-war period.  The Manhattan Project existed for just five years. In 1943, 75 years ago, the Manhattan Project transitioned from planning to construction and initial operation of the first US nuclear weapons complex facilities.   Here’s a very brief timeline for the Manhattan Project.

  • 13 August 1942: The Manhattan Engineer District was formally created under the leadership of U.S. Army Colonel Leslie R. Groves.
  • 2 December 1942: A team led by Enrico Fermi achieved the world’s first self-sustaining nuclear chain reaction in a graphite-moderated, natural uranium fueled reactor known simply as Chicago Pile-1 (CP-1).
  • 1943 – 1946: The Manhattan Project managed the construction and operation of the entire US nuclear weapons complex.
  • 16 July 1945: The first nuclear device was successfully tested at the Trinity site near Alamogordo, NM, less than three years after the Manhattan Project was created.
  • 6 & 9 August 1945:  Atomic bombs were employed by the US against Japan, contributing to ending World War II.
  • 1 January 1947:  The newly formed, civilian-led Atomic Energy Commission (AEC) took over management and operation of all research and production facilities from the Manhattan Engineer District.
  • 25 August 1947: The Manhattan Engineer District was abolished.

The WW II nuclear weapons complex was the foundation for the early US post-war nuclear weapons infrastructure that evolved significantly over time to support the US mutually-assured destruction strategy during the Cold War with the Soviet Union.  Today, the US nuclear weapons complex continues to evolve as needed to perform its critical role in maintaining the US nuclear deterrent capability.

2.  A Closer Look at the Manhattan Project Timeline

You’ll find a comprehensive, interactive timeline of the Manhattan Project on the Department of Energy’s (DOE) OSTI website at the following link:

The Atomic Heritage Foundation is dedicated to “supporting the Manhattan Project National Historical Park and capturing the memories of the people who harnessed the energy of the atom.”  Their homepage is here:

A similar atomic timeline created by the Atomic Heritage Foundation is available for your browsing pleasure here:

3.  The Manhattan Project National Historical Park

The Manhattan Project National Historical Park was authorized by Congress in December 2014 and subsequently was approved by the President to commemorate the Manhattan Project. The Manhattan Project National Historical Park is an extended “park” that currently is comprised of three distinct DOE sites that each had different missions during WW II: 

  • Los Alamos, New Mexico: Nuclear device design, test and production
  • Oak Ridge, Tennessee: Enriched uranium production
  • Hanford, Washington: Plutonium production

On 10 November 2015, a memorandum of agreement between DOE and the National Park Service (NPS) established the park and the respective roles of DOE and NPS in managing the park and protecting and presenting certain historic structures to the public.

You’ll find the Manhattan Project National Historical Park website here:

Following is a brief overview of the three sites that currently comprise the Manhattan Project National Historical Park.

3.1. Los Alamos, New Mexico

Los Alamos Laboratory was established 75 years ago, in early 1943, as MED Site Y, under the direction of J. Robert Oppenheimer. This was the Manhattan Project’s nuclear weapons laboratory, which was created to consolidate in one secure, remote location most of the research, design, development and production work associated producing usable nuclear weapons to the US Army during WW II. 

Los Alamos Laboratory main gate circa 1944. Source: Los Alamos National Laboratory

The first wave of scientists began arriving at Los Alamos Laboratory in April 1943.  Just 27 months later, on 16 July 1945, the world’s first nuclear device was detonated 200 miles south of Los Alamos at the Trinity Site near Alamogordo, NM.  This was the plutonium-fueled, implosion-type device code named “Gadget.”  

During WW II, the Los Alamos Laboratory produced three atomic bombs:

  • One uranium-fueled, gun-type atomic bomb code named “Little Boy” was produced. This was the atomic bomb dropped on Hiroshima, Japan on 6 August 1945, making it the first nuclear weapon used in warfare.  This atomic bomb design was not tested before it was used operationally.
  • Two plutonium-fueled, implosion-type atomic bombs code named “Fat Man” were produced.  These bombs were very similar to Gadget.  One of the Fat Man bombs was dropped on Nagasaki, Japan on 9 August 1945.  The second Fat Man bomb could have been used during WW II, but it was not needed after Japan announced its surrender on 15 August 1945.

The highly-enriched uranium for the Little Boy bomb was produced by the enrichment plants at Oak Ridge.  The plutonium for Gadget and the two Fat Man bombs was produced by the production reactors at Hanford.

Three historic sites are on Los Alamos National Laboratory property and currently are not open to the public:

  • Gun Site Facilities: three bunkered buildings (TA-8-1, TA-8-2, and TA-8-3), and a portable guard shack (TA-8-172).
  • V-Site Facilities: TA-16-516 and TA-16-517 V-Site Assembly Building
  • Pajarito Site: TA-18-1 Slotin Building, TA-8-2 Battleship Control Building, and the TA-18-29 Pond Cabin.

You’ll find information on the Manhattan Project National Historical Park sites at Los Alamos here:

Also visit the Atomic Heritage Foundation’s webpage on Los Alamos here:

3.2. Oak Ridge, Tennessee

Land acquisition was approved in 1942 for planned uranium “atomic production plants” in the Tennessee Valley.  The selected site officially became the Clinton Engineer Works (CEW) in January 1943 and was given the MED code name Site X.  This is where MED and its contractors managed the deployment during WW II of the following three different uranium enrichment technologies in three separate, large-scale industrial process facilities:  

  • Liquid thermal diffusion process, based on work by Philip Abelson at Naval Research Laboratory and the Philadelphia Naval Yard.  This process was implemented at S-50, which produced uranium enriched to < 2 at. % U-235.
  • Gaseous diffusion process, based on work by Harold Urey at Columbia University.  This process was implemented at K-25, which produced uranium enriched to about 23 at. % U-235 during WW II. 
  • Electromagnetic separation process, based on Ernest Lawrence’s invention of the cyclotron at the University of California Berkeley in the early 1930s.  This process was implemented at Y-12 where the final output was weapons-grade uranium.  

The Little Boy atomic bomb used 92.6 pounds (42 kg) of highly enriched uranium produced at Oak Ridge with contributions from all three of these processes.

The nearby township was named Oak Ridge in 1943, but the nuclear site itself was not officially renamed Oak Ridge until 1947.

The three Manhattan Project National Historical Park sites at Oak Ridge are:

  • X-10 Graphite Reactor National Historic Landmark
  • K-25 complex
  • Y-12 complex: Buildings 9731 and 9204-3 

The S-50 Thermal Diffusion Plant was dismantled in the late 1940s. This site is not part of the Manhattan Project National Historical Park.

Following is a brief overview of X-10, K-25 and Y-12 historical sites. There’s much more information on the Manhattan Project National Historical Park sites at Oak Ridge here:

Also visit the Atomic Heritage Foundation’s webpage on Oak Ridge here:

X-10 Graphite Reactor

X-10 was the world’s second nuclear reactor (after the Chicago Pile, CP-1) and the first reactor designed and built for continuous operation. It was intended to produce the first significant quantities of plutonium, which were used by scientists at Los Alamos to characterize plutonium and develop the design of a plutonium-fueled atomic bomb.  

X-10 was a large graphite-moderated, natural uranium fueled reactor that originally had an continuous design power rating of 1.0 MWt, which later was raised to 3.5 MWt. Originally, it was intended to be a prototype for the much larger plutonium production reactors being planned for Hanford.  The selection of air cooling for X-10 enabled this reactor to be deployed more rapidly, but limited its value as a prototype for the future water-cooled plutonium production reactors.

The X-10 reactor core was comprised of graphite blocks arranged into a cube measuring 24 feet (7.3 meters) on each side.  The core was surrounded by several feet of high-density concrete and other material to provide radiation shielding.  The core and shielding were penetrated by 1,248 horizontal channels arranged in 36 rows. Each channel served to position up to 54 fuel slugs in the core and provide passages for forced air cooling of the core. Each fuel slug was an aluminum clad, metallic natural uranium cylinder measuring 4 inches (10.16 cm) long x 1.1 inches (2.79 cm) in diameter.  New fuel slugs were added manually at the front face (the loading face) of the reactor and irradiated slugs were pushed out through the back face of the reactor, dropping into a cooling water pool.  The reactor was controlled by a set of vertical control rods.

The basic geometry of the X-10 reactor is shown below.

X-10 Graphite Reactor general arrangement.  Source: Department of Energy / Oak Ridge via
Workers load fuel slugs into the X-10 Graphite Reactor circa 1952.  Source: US Army / Manhattan Engineer District – Ed Westcott / American Museum of Science and Energy /

Site construction work started 75 years ago, on 27 April 1943. Initial criticality occurred less than seven months later, on 4 November 1943.  

Plutonium was recovered from irradiated fuel slugs in a pilot-scale chemical separation line at Oak Ridge using the bismuth phosphate process.  In April 1944, the first sample (grams) of reactor-bred plutonium from X-10 was delivered to Los Alamos.  Analysis of this sample led Los Alamos scientists to eliminate one candidate plutonium bomb design (the “Thin Man” gun-type device) and focus their attention on the Fat Man implosion-type device. X-10 operated as a plutonium production reactor until January 1945, when it was turned over to research activities.  X-10 was permanently shutdown on 4 November 1963, and was designated a National Historic Landmark on 15 October 1966.

K-25 Gaseous Diffusion Plant

Preliminary site work for the K-25 gaseous diffusion plant began 75 years ago, in May 1943, with work on the main building starting in October 1943. The six-stage pilot plant was ready for operation on 17 April 1944.  

K-25 site circa 1944.  Source:

The K-25 gaseous diffusion plant feed material was uranium hexafluoride gas (UF6) from natural uranium and slightly enriched uranium from both the S-50 liquid thermal diffusion plant and the first (Alpha) stage of the Y-12 electromagnetic separation plant.  During WW II, the K-25 plant was capable of producing uranium enriched up to about 23 at. % U-235.  This product became feed material for the second (Beta) stage of the Y-12 electromagnetic separation process, which continued the enrichment process and produced weapons-grade U-235.

As experience with the gaseous diffusion process improved and additional cascades were added, K-25 became capable of delivering highly-enriched uranium after WW II.

You can take a virtual tour of K-25, including its decommissioning and cleanup, here:

Construction on the second Oak Ridge gaseous diffusion plant, K-27, began on 3 April 1945.  This plant became operational after WW II.  By 1955, the K-25 complex had grown to include gaseous diffusion buildings K-25, K-27, K-29, K-31 and K-33 that comprised a multi-building, enriched uranium production chain collectively known as the Oak Ridge Gaseous Diffusion Plant (ORGDP). Operation of the ORGDP continued until 1985.

Additional post-war gaseous diffusion plants based on the technology developed at Oak Ridge were built and operated in Paducah, KY (1952 – 2013) and Portsmouth, OH (1954 – 2001).

Y-12 Electromagnetic Separation Plant

In 1941, Earnest Lawrence modified the 37-inch (94 cm) cyclotron in his laboratory at the University of California Berkeley to demonstrate the feasibility of electromagnetic separation of uranium isotopes using the same principle as a mass spectrograph.

The initial industrial-scale design agreed in 1942 was called an Alpha (α) calutron, which was designed to enrich natural uranium (@ 0.711 at.% U-235) to >10 at.% U-235.  The later Beta (β) calutron was designed to further enrich the output of the Alpha calutrons, as well as the outputs from the K-25 and S-50 processes, and produce weapons-grade uranium at >88 at.% U-235.

The calutrons required large magnet coils to establish the strong electromagnetic field needed to separate the uranium isotopes U-235 and U-238. The shape of the magnet coils for both the Alfa and Beta calutrons resembled a racetrack, with many individual calutron modules (aka “tanks”) arranged side-by-side around the racetrack.  At Y-12, there were nine Alpha calutron “tracks” (5 x Alpha-1 and 4 x Alpha-2 tracks), each with 96 calutron modules (tanks), for a total of 864 Alpha calutrons.  In addition, there were eight Beta calutron tracks, each with 36 calutron modules, for a total of 288 beta calutrons, only 216 of which ever operated.

Due to wartime shortages of copper, the Manhattan Project arranged a loan from the Treasury Department of about 300 million Troy ounces (10,286 US tons) of silver for use in manufacturing the calutron magnet coils. A general arrangement of a Beta calutron module (tank) is shown in the following diagram, which also shows the isotope flight paths from the uranium tetrachloride  (UCl4) ion source to the ion receivers.  Separated uranium was recovered by burning the graphite ion receivers and extracting the metallic uranium from the ash.

General arrangement of a Beta calutron module (tank).  Source:  Oak Ridge drawing 42951, via Yergey & Yergey, 1997
An Alpha calutron “racetrack” comprised of 96 individual calutron modules (tanks).  Source: Department of Energy, Oak Ridge via

Construction of Buildings 9731 and 9204-3 at the Y-12 complex began 75 years ago, in February 1943.  By February 1944, initial operation of the Alpha calutrons had produced only 0.44 pounds (0.2 kg) of U-235 @ 12 at.%. By August 1945, the Y-12 Beta calutrons had produced the 92.6 pounds (42 kg) of weapons-grade uranium needed for the Little Boy atomic bomb.

After WW II, the silver was recovered from the calutron magnet coils and returned to the Treasury Department.

3.3. Hanford, Washington

On January 16, 1943, General Leslie Groves officially endorsed Hanford as the proposed plutonium production site, which was given the MED code name Site W. The plan was to construct three large graphite-moderated, water-cooled plutonium production reactors, designated B, D, and F, in along the Columbia River.  The Hanford site also would include a facility for manufacturing the new uranium fuel slugs for the reactors as well as chemical separation plants and associated facilities to recover and process plutonium from the irradiated uranium slugs.

After WW II, six more plutonium production reactors were built at Hanford along with additional plutonium and nuclear waste processing and storage facilities.

The Manhattan Project National Historical Park sites at Hanford are:

  • B Reactor, which has been a National Historic Landmark since 19 August 2008
  • The previous Hanford High School in the former Town of Hanford and Hanford Construction Camp Historic District
  • Bruggemann’s Agricultural Warehouse Complex
  • White Bluffs Bank and Hanford Irrigation District Pump House

A brief overview of the B Reactor and the other Hanford production reactors is provided below.  There’s more information on the Manhattan Project National Historical Park sites at Hanford here:

Also visit the Atomic Heritage Foundation’s webpage on Hanford here:

The Manhattan Project National Historical Park does not include the Hanford chemical separation plants and associated plutonium facilities in the 200 Area, the uranium fuel production plant in the 300 Area, or the other eight plutonium production reactors that were built in the 100 Area. Information on all Hanford facilities, including their current cleanup status, is available on the Hanford website here:

B Reactor

The B Reactor at the Hanford Site was the world’s first full-scale reactor and the first of three plutonium production reactor of the same design that became operational at Hanford during WW II.  B Reactor and the similar D and F Reactors were significantly larger graphite-moderated reactor than the X-10 Graphite Reactor at Oak Ridge.  The rectangular reactor core measured 36 feet (11 m) wide x 36 feet (11 m) tall x 28 feet (8.53 m) deep, surrounded by radiation shielding. These reactors were fueled by aluminum clad, metallic natural fuel slugs measuring 8 inches (20.3 cm) long x 1.5 inches (3.8 cm) in diameter.  As with the X-10 Graphite Reactor, new fuel slugs were inserted into process tubes (fuel channels) at the front face of the reactor. The irradiated fuel slugs were pushed out of the fuel channels at the back face of the reactor, falling into a water pool to allow the slugs to cool before further processing for plutonium recovery.

Reactor cooling was provided by the once-through flow of filtered and processed fresh water drawn from the Columbia River.  The heated water was discharged from the reactor into large retention basins that allowed some cooling time before the water was returned to the Columbia River.

Hanford production reactor general arrangement (Typical of B, D & F Reactor).  Source:  DOE/RL-97-1047, Department of Energy (DOE)
Hanford production reactor core general arrangement (Typical of B, D, F, H, DR and C).  Source: DOE
The front face (loading face) of B Reactor.  Source: DOE

Construction of B Reactor began 75 years ago, in October 1943, and fuel loading started 11 months later, on September 13, 1944.  Initial criticality occurred on 26 September 1944, followed shortly by operation at the initial design power of 250 MWt.

B Reactor was the first reactor to experience the effects of xenon poisoning due to the accumulation of Xenon (Xe-135) in the uranium fuel. Xe-135 is a decay product of the relatively short-lived (6.7 hour half-life) fission product iodine I-135.  With its very high neutron cross-section, Xe-135 absorbed sufficient neutrons to significantly, and unexpectedly, reduce B Reactor power. Fortunately, DuPont had added more process tubes (a total of 2004) than called for in the original design of B Reactor. After the xenon poisoning problem was understood, additional fuel was loaded, providing the core with enough excess reactivity to override the neutron poisoning effects of Xe-135.

On 3 February 1945, the first batch of B Reactor plutonium was delivered to Los Alamos, just 10 months after the first small plutonium sample from the X-10 Graphite Reactor had been delivered.

B Reactor plutonium production complex at Hanford, in its heyday.  Source: DOE
B Reactor at Hanford today.  Source: DOE

Regular plutonium deliveries from the Hanford production reactors provided the plutonium needed for the first ever nuclear device (the Gadget) tested at the Trinity site near Alamogordo, NM on 16 July 1945, as well as for the Fat Man atomic bomb dropped on Nagasaki, Japan on 9 August 1945 and an unused second Fat Man atomic bomb. These three devices each contained about 13.7 pounds (6.2 kilograms) of weapons-grade plutonium produced in the Hanford production reactors.

From March 1946 to June 1948, B Reactor was shut down for maintenance and modifications.  In March 1949, B Reactor began the first tritium production campaign, irradiating targets containing lithium and producing tritium for hydrogen bombs.  

By 1963, B Reactor was permitted to operate at a maximum power level of 2,090 MWt.  B Reactor continued operation until 29 January 1968, when it was ordered shut down by the Atomic Energy Commission.  Because of its historical significance, B Reactor was given special status that allows it to be open for public tours as part of the Manhattan Project National Historical Park.

The Other WW II Production Reactors at the Hanford Site:  D & F

During WW II, three plutonium reactors of the same design were operational at Hanford: B, D and F.  All had an initial design power rating of 250 MWt and by 1963 all were permitted to operate at a maximum power level of 2,090 MWt.

  • D Reactor:  This was the world’s second full-scale nuclear reactor.  It became operational in December 1944, but experienced operational problems early in life due to growth and distortion of its graphite core.  After developing a process for controlling graphite distortion, D Reactor operated successfully through June 1967.
  • F Reactor:  This was the third of the original three production reactors at Hanford.  It became operational in February 1945 and ran for more than twenty years until it was shut down in June1965.

D and F Reactors currently are in “interim safe storage,” which commonly is referred to as “cocooned.”  These reactor sites are not part of the Manhattan Project National Historical Park.

Post-war Production Reactors at Hanford: H, DR, C, K-West, K-East & N

After WW II, six additional plutonium production reactors were built and operated at Hanford. The first three, named H, DR and C, were very similar in design to the B, D and F Reactors.  The next two, K-West and K-East, were of similar design, but significantly larger than their predecessors.  The last reactor, named N, was a one-of-a kind design.

  • H Reactor:  This was the first plutonium production reactor built at Hanford after WW II. It became operational in October 1949 with a design power rating of 400 MWt and by 1963 was permitted to operate at a maximum power level of 2,090 MWt. It operated for 15 years before being permanently shut down in April 1965.
  • DR Reactor:  This reactor originally was planned as a replacement for the D Reactor and was built adjacent to the D Reactor site. DR became operational in October 1950 with an initial design power rating of 250 MWt. It operated in parallel with D Reactor for 14 years, and by 1963 was permitted to operate at the same maximum power level of 2,090 MWt.  DR was permanently shut down in December 1964.
  • C Reactor:  Reactor construction started June 1951 and it was completed in November 1952, operating initially at a design power of 650 MWt. By 1963, C Reactor was permitted to operate at a maximum power level of 2,310 MWt.  It operated for sixteen years before being shut down in April 1969.  C Reactor was the first reactor at Hanford to be placed in interim safe storage, in 1998.
  • K-West & K-East Reactors:  These larger reactors differed from their predecessors mainly in the size of the moderator stack, the number, size and type of process tubes (3,220 process tubes), the type of shielding and other materials employed, and the addition of a process heat recovery system to heat the facilities.  These reactors were built side-by-side and became operational within four months of each other in 1955: K-West in January and K-East in April.  These reactors initially had a design power of 1,800 MWt and by 1963 were permitted to operate at a maximum power level of 4,400 MWt before an administrative limit of 4,000 MWt was imposed by the Atomic Energy Commission. The two reactors ran for more than 15 years.  K-West was permanently shut down in February 1970 followed by K-East in January 1971.
  • N Reactor:  This was last of Hanford’s nine plutonium production reactors and the only one designed as a dual-purpose reactor capable of serving as a production reactor while also generating electric power for distribution to the external power grid.  The N Reactor had a reactor design power rating of 4,000 MWt and was capable of generating 800 MWe. The N Reactor also was the only Hanford production reactor with a closed-loop primary cooling system.  Plutonium production began in 1964, two years before the power generating part of the plant was completed in 1966.  N Reactor operated for 24 years until 1987, when it was shutdown for routine maintenance.  However, it never restarted, instead being placed in standby status by DOE and then later retired.

Four of these reactors (H, DR, C and N) are in interim safe storage while the other two (K-West and K-East) are being prepared for interim safe storage.  None of these reactor sites are part of the Manhattan Project National Historical Park.

The Federation of American Scientists (FAS) reported that the nine Hanford production reactors produced 67.4 metric tons of plutonium, including 54.5 metric tons of weapons-grade plutonium, through 1987 when the last Hanford production reactor (N Reactor) was shutdown.

4. Other Manhattan Project Sites

There are many MED sites that are not yet part of the Manhattan Project National Historical Park.  You’ll find details on all of the MED sites on the American Heritage Foundation website, which you can browse at the following link:

Another site worth browsing is the interactive world map created by the ALSOS Digital Library for Nuclear Issues on Google Maps to show the locations and provide information on offices, mines, mills, plants, laboratories, and test sites of the US nuclear weapons complex from World War II to 2016. The map includes over 300 sites, including the Manhattan Project sites.  I think you’ll enjoy exploring this interactive map.

Source: Google maps / ALSOS Digital Library for Nuclear Issues

5. Additional reading:

Following is a list of other online resources where you can find additional information related to this post.

Los Alamos:

J. Jadrnak, “Renovated museum casts spotlight on human history of Los Alamos,” Albuquerque Journal, 30 December 2016

Oak Ridge site and uranium enrichment processes:

“Oak Ridge National Laboratory: The First Fifty Years,” REView magazine, Vol. 25, No 3, Oak Ridge National Laboratory, July 1992

Greene, Sherrell R., “A diamond in Dogpatch: The 75th anniversary of the Graphite Reactor – Part I: The War Years,” American Nuclear Society, November 2018

Greene, Sherrell R., “A diamond in Dogpatch:  The 75th anniversary of the Graphite Reactor – Part 2: The Postwar Years,” American Nuclear Society, December 2018

Yergey, A.L. and Yergey, A.K., “Preparative Scale Mass Spectrometry: A Brief History of the Calutron,” Journal American Society for Mass Spectrometry, 1997, 8, 943–953

“Uranium Enrichment Processes Directed Self-Study Course, Module 5.0: Electromagnetic Separation (Calutron) and Thermal Diffusion,” US Nuclear Regulatory Commission Technical Training Center, 9/08 (Rev 3)

“Uranium Enrichment Processes Directed Self-Study Course, Module 2.0: Gaseous Diffusion,” US Nuclear Regulatory Commission Technical Training Center, 9/08 (Rev 3)

Hanford site, plutonium production reactors and processing facilities:

“Hanford Site Historical District: History of the Plutonium Production Facilities 1943-1990,” DOE/RL-97-1047, Department of Energy, Hanford Cultural and Historical Resources Program, June 2002

Gerber, M.S.,  “The Plutonium Production Story at the Hanford Site:  Processes and Facilities History,” WHC-MR-0512, Westinghouse Hanford Company, June 1996

“Operating Limits – Hanford Production Reactors,” HW-76327, Research and Engineering Operation, Irradiation Processing Department, 5 November 1963

“Manhattan Project – B Reactor – Hanford, Washington, World’s first full-scale nuclear reactor,” US Department of Energy, Office of Environmental Management, 2009

“Hanford’s Historic B Reactor – Presentation to PNNL Open World Forum March 20, 2009,” HNF-40918-VA, Department of Energy, 2009

Nave, R., “Xenon Poisoning,” HyperPhysics, Georgia State University

What to do with Carbon Dioxide

In my 17 December 2016 post, “Climate Change and Nuclear Power,” there is a chart that shows the results of a comparative life cycle greenhouse gas (GHG) analysis for 10 electric power-generating technologies. In that chart, it is clear how carbon dioxide capture and storage technologies can greatly reduce the GHG emissions from gas and coal generators.

An overview of carbon dioxide capture and storage technology is presented in a December 2010 briefing paper issued by the London Imperial College. This paper includes the following process flow diagram showing the capture of CO2 from major sources, use or storage of CO2 underground, and use of CO2 as a feedstock in other industrial processes. Click on the graphic to enlarge.

Carbon capture and storage process

You can download the London Imperial College briefing paper at the following link:—-Grantham-BP-4.pdf

Here is a brief look at selected technologies being developed for underground storage (sequestration) and industrial utilization of CO2.

Store in basalt formations by making carbonate rock

Iceland generates about 85% of its electric power from renewable resources, primarily hydro and geothermal. Nonetheless, Reykjavik Energy initiated a project called CarbFix at their 303 MWe Hellisheidi geothermal power plant to control its rather modest CO2 emissions along with hydrogen sulfide and other gases found in geothermal steam.

Hellisheidi geothermal power plantHellisheidi geothermal power plant. Source: Power Technology

The process system collects the CO2 and other gases, dissolves the gas in large volumes of water, and injects the water into porous, basaltic rock 400 – 800 meters (1,312 – 2,624 feet) below the surface. In the deep rock strata, the CO2 undergoes chemical reactions with the naturally occurring calcium, magnesium and iron in the basalt, permanently immobilizing the CO2 as environmentally benign carbonates. There typically are large quantities of calcium, magnesium and iron in basalt, giving a basalt formation a large CO2 storage capacity.

The surprising aspect of this process is that the injected CO2 was turned into hard rock very rapidly. Researchers found that in two years, more that 95% of the CO2 injected into the basaltic formation had been turned into carbonate.

For more information, see the 9 June 2016 Washington Post article by Chris Mooney, “This Iceland plant just turned carbon dioxide into solid rock — and they did it super fast,” at the following link:

The author notes,

“The researchers are enthusiastic about their possible solution, although they caution that they are still in the process of scaling up to be able to handle anything approaching the enormous amounts of carbon dioxide that are being emitted around the globe — and that transporting carbon dioxide to locations featuring basalt, and injecting it in large volumes along with even bigger amounts of water, would be a complex affair.”

Basalt formations are common worldwide, making up about 10% of continental rock and most of the ocean floor. Iceland is about 90% basalt.

Detailed results of this Reykjavik Energy project are reported in a May 2016 paper by J.M. Matter, M. Stute, et al., Rapid carbon mineralization for permanent disposal of anthropogenic carbon dioxide emissions,” which is available on the Research Gate website at the following link:

Similar findings were made in a separate pilot project in the U.S. conducted by Pacific Northwest National Laboratory and the Big Sky Carbon Sequestration Partnership. In this project, 1,000 tons of pressurized liquid CO2 were injected into a basalt formation in eastern Washington state in 2013. Samples taken two years later confirmed that the CO2 had been converted to carbonate minerals.

These results were published in a November 2016 paper by B. P McGrail, et al., “Field Validation of Supercritical CO2 Reactivity with Basalts.” The abstract and the paper are available at the following link:

Store in fractures in deep crystalline rock

Lawrence Berkeley National Laboratory has established an initiative dubbed SubTER (Subsurface Technology and Engineering Research, Development and Demonstration Crosscut) to study how rocks fracture and to develop a predictive understanding of fracture control. A key facility is an observatory set up 1,478 meters (4,850 feet) below the surface in the former Homestake mine near Lead, South Dakota (note: Berkeley shares this mine with the neutrino and dark matter detectors of the Sanford Underground Research Facility). The results of the Berkeley effort are expected to be applicable both to energy production and waste storage strategies, including carbon capture and sequestration.

You can read more about this Berkeley project in the article, “Underground Science: Berkeley Lab Digs Deep For Clean Energy Solutions,” on the Global Energy World website at the following link:

Make ethanol

Researchers at the Department of Energy’s Oak Ridge National Laboratory (ORNL) have defined an efficient electrochemical process for converting CO2 into ethanol. While direct electrochemical conversion of CO2 to useful products has been studied for several decades, the yields of most reactions have been very low (single-digit percentages) and some required expensive catalysts.

Key points about the new process developed by ORNL are:

  • The electro-reduction process occurs in CO2 saturated water at ambient temperature and pressure with modest electrical requirements
  • The nanotechnology catalyst is made from inexpensive materials: carbon nanospike (CNS) electrode with electro-nucleated copper nanoparticles (Cu/CNS). The Cu/CNS catalyst is unusual because it primarily produces ethanol.
  • Process yield (conversion efficiency from CO2 to ethanol) is high: about 63%
  • The process can be scaled up.
  • A process like this could be used in an energy storage / conversion system that consumes extra electricity when it’s available and produces / stores ethanol for later use.

You can read more on this process in the 19 October 2016 article, “Scientists just accidentally discovered a process that turns CO2 directly into ethanol,” on the Science Alert website at the following link

The full paper is available on the Chemistry Select website at the following link:





New Catalyst Could Greatly Reduce the Cost of Splitting Water

Splitting water (H2O) is the process of splitting the water molecule into its constituent parts: hydrogen (H2) and oxygen (O2). A catalyst is a substance that speeds up a chemical reaction or lowers the energy required to get a reaction started, without being consumed itself in a chemical reaction.

Water moleculeWater molecule.  Source: Laguna Design, Getty Images

A new catalyst, created as a thin film crystal comprised of one layer of iridium oxide (IrOx) and one layer of strontium iridium oxide (SrIrO3), is described in a September 2016 article by Umair Irfan entitled, “How Catalyst Could Split Water Cheaply.” This article is available on the Scientific American website at the following link:

The new catalyst, which is the only known catalyst to work in acid, applies to the oxygen evolution reaction; the slower half of the water-splitting process.

Author Irfan notes that, “Many of the artificial methods of making hydrogen and oxygen from water require materials that are too expensive, require too much energy or break down too quickly in real-world conditions…” The availability of a stable catalyst that can significantly improve the speed and economics of water splitting could help promote the shift toward more widespread use of clean, renewable fuels. The potential benefits include:

  • May significantly improve hydrogen fuel economics
  • May allow water splitting to compete with other technologies (i.e., batteries and pumped storage) for energy storage. See my 4 March 2016 posting on the growing need for grid energy storage.
  • May improve fuel cells

At this point, it is not clear exactly how the IrOx / SrIrO3 catalyst works, so more research is needed before the practicality of its use in industrial processes can be determined.

The complete paper, “A highly active and stable IrOx/SrIrO3 catalyst for the oxygen evolution reaction,” by Seitz, L. et al., is available to subscribers on the Science magazine website at the following link:


A Brief History of Fireworks

There is a good history of fireworks by Joe Carmichael posted on the INVERSE website at the following link:

Here, you can scroll through an illustrated timeline (see screenshot, below) from the advent of bamboo firecrackers in 200 BCE to modern day fireworks.

Tiimeline of fireworks  Source: INVERSE

Of local interest, the timeline includes the July 4th 2012 San Diego Big Bay Boom (aka Big Bay Bust), when a technical malfunction caused all fireworks on multiple barges in the bay to be fired prematurely in a spectacular 30 second pyrotechnic display.

San Diego 2012 Big Bay Bust  Source: YouTube

In case you missed the actual event, you can see a (short) video at the following link:

My personal favorite is the Sydney, Australia New Year’s fireworks display, which begins with what looks like an explosive demolition of the Harbor Bridge and then continues with the spectacular main event seen in the photos below.

2016 New-Years-Eve-Sydney-Fireworks2016 sydney-fireworks-ceremonySource:

You can see a short video of the start of Sydney’s 2016 New Year’s fireworks at the following link:



Radioisotope Thermoelectric Generators (RTG) for Spacecraft: History and Current U.S. Pu-238 Production Status

Radioisotope Thermoelectric Generators (RTG), also called Radioisotope Power Systems (RTS), commonly use non-weapons grade Plutonium 238 (Pu-238) to generate electric power and heat for National Aeronautics and Space Administration (NASA) spacecraft when solar energy and batteries are not adequate for the intended mission.

Approximately 300 kg (661 lb) of Pu-238 was produced by the Department of Energy (DOE) at the Savannah River Site between 1959 – 1988. After U.S production stopped, the U.S. purchased Pu-238 from Russia until that source of supply ended in 2010.

Limited production of new Pu-238 in the U.S re-started in 2013 using the process shown below. This effort is partially funded by NASA.  Eventually, production capacity will be about 1.5 kg (3.3 lb) Pu-238 per year. The roles of the DOE national laboratories involved in this production process are as follows:

  • Idaho National Engineering Lab (INEL):
    • Store the Neptunium dioxide (NpO2) feed stock
    • Deliver feed stock as needed to ORNL
    • Irradiate targets provided by ORNL in the Advanced Test Reactor (ATR)
    • Return irradiated targets to ORNL for processing
  • Oak Ridge National Lab (ORNL):
    • Manufacture targets
    • Ship some targets to INEL for irradiation
    • Irradiate the remaining targets in the High Flux Isotope Reactor (HFIR)
    • Process all irradiated targets to recover and purify Pu-238
    • Convert Pu-238 to oxide and deliver as needed to LANL
  • Los Alamos National Lab (LANL):
    • Manufacture the Pu-238 fuel pellets for use in RTGs

Pu-238 production process

Diagram source: Ralph L McNutt, Jr, Johns Hopkins University APL, 2014

The U.S. has an existing inventory of  about 35 kg (77 lb) of Pu-238 of various ages.  About half is young enough to meet the power specifications of planned NASA spacecraft. The remaining stock is more than 20 years old, has decayed significantly since it was produced, and does not meet specifications.   The existing inventory will be blended with newly produced Pu-238 to extend the usable inventory. To get the energy density needed for space missions while extending the supply of Pu-238, DOE and NASA plan to blend “old” Pu-238 with newly produced Pu-238 in 2:1 proportions.

NASA slowly has been developing an Advanced Stirling Radioisotope Generator (ASRG), which should be capable of producing about four times the power of older RTGs per unit of Pu-238. However, the ASRG produces less waste heat, which can be used productively to warm electronics in the interior of a spacecraft, such as the Mars rover Curiosity. The ASRG may not be available in time for the next space mission requiring an RTG power source, in which case an existing RTG design will be used.

Read a history of RTGs and more information on current U.S. Pu-238 production status in a 2014 presentation by Ralph L McNutt, Jr, at the following link:

9 February 2016 Update

On 22 December 2015, DOE reported production of 50 grams of new Pu-238.

DOE reported that it plans to set an initial production target of 300 – 400 grams (about 12 ounces) of Pu-238 per year. After implementing greater automation and scaling up the process, ORNL expects to reach the the production target of 1.5 kg (3.3 lb) Pu-238 per year.

The next NASA mission that will use an RTG is the Mars 2020 rover, which will use the same Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) as used on NASA’s Mars rover Curiosity. MMRTG can provide about 110 watts of electrical power to a spacecraft and its science instruments at the beginning of a mission.

You can read the ORNL announcement of initial Pu-238 production at the following link:

3 January 2019 Update:

In the past three years, ORNL has made scant progress in producing Pu-238.  In a 13 December 2018 article, “NASA Doesn’t Have Enough Nuclear Fuel For Its Deep Space Missions,”author Ethan Siegel reports:  “Although current production (at ORNL) yields only a few hundred grams per year (less than a pound), the laboratory has the eventual goal of ramping up to 1.5 kilograms (3.3 pounds) per year by 2023, at the earliest.  Ontario Power Generation in Canada has also begun producing Pu-238, with the goal of using it as a supplemental source for NASA.”  You can read the complete article on the Forbes website at the following link:

The Canadian plans for becoming a source of Pu-238 was announced on 1 March 2017:  “Ontario Power Generation (OPG) and its venture arm, Canadian Nuclear Partners, are participating in a project to produce isotopes in support of deep space exploration. Under the agreement, OPG would help create isotopes at the Darlington nuclear station east of Toronto that will help power space probes.” You can read the complete OPG press release here:

Also see the OPG public relations piece, “OPG looks to the stars,”  here: