ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
Apr 2024
Jan 2024
Latest Journal Issues
Nuclear Science and Engineering
June 2024
Nuclear Technology
May 2024
Fusion Science and Technology
Latest News
Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Yong Hoon Jeong, Mujid S. Kazimi
Nuclear Technology | Volume 159 | Number 2 | August 2007 | Pages 147-157
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT07-A3861
Articles are hosted by Taylor and Francis Online.
The hybrid sulfur cycle (often called the Westinghouse cycle) for decomposing water into hydrogen and oxygen has two steps. The sulfuric acid is decomposed into steam and sulfur trioxide, which is further decomposed into sulfur dioxide and oxygen at high temperature (~1100 K). Hydrogen is produced by electrolysis of a sulfur dioxide and water mixture at low temperature, which also results in the formation of oxygen and sulfuric acid.In this study, separation of decomposed products and internal heat recuperation are examined, and ways to optimize the energy efficiency of the hybrid cycle are explored by varying the electrolyzer acid concentration, decomposer acid concentration, pressure and temperature of the decomposer, and the internal heat recuperation. The analysis is based on currently available experimental data for the electrode potential.A cycle efficiency of 45.3% [lower heating value (LHV)] appears to be achievable at 1100 K (10 bar, 1100 K, and 60 mol% of H2SO4 for the decomposer, 60 wt% of H2SO4 for the electrolyzer). For a maximum temperature of 1200 K, 50.5% (LHV) appears to be the achievable cycle efficiency (10 bar, 1200 K, and 60 mol% of H2SO4 for the decomposer, 60 wt% of H2SO4 for the electrolyzer). Operation under elevated pressures (70 bar or higher) results in loss of cycle efficiencies due to lower yield of the SO2 in the decomposer but minimizes equipment size and possibly capital cost. However, the loss in efficiency as pressure increases is not large at high temperature (1200 K) compared to that at low temperatures (1000 to 1100 K). Therefore, high-pressure operation for minimizing capital investment would be favored only if the high temperature can be accommodated. The major factors that can affect the cycle efficiency are reducing the electrode overpotential and having structural materials that can accommodate operation at high temperature and high acid concentration.