Dynamics of Bed for Regeneration of Cerium Oxide High-Temperature Coal Gas Desulfurization Sorbent

The dynamic behavior of bed for regeneration of cerium oxide high temperature gas desulfurization sorbent under the atmosphere of O2 was investigated in the fixed bed micro-reactor. O2 concentration during the regeneration can be detected by an oxygen analyzer, and the sulfur content of sorbent in the bed was test using sulfur analyzer. The effects of O2 concentration, regeneration temperature on the dynamic behavior of bed for regeneration of CeO2 desulfurization sorbent were discussed. According to the experimental results, the length and movement speed of regeneration zone are calculated. The results showed that the increase of O2 concentration in inlet gas obviously improves the movement speed of regeneration zone in bed for CeO2 desulfurization sorbent, and the increase of regeneration temperature can decreased the length of the regeneration zone and improved the movement speed of the regeneration zone. The increase of regeneration temperature had a better effect on the improvement of bed utilization of sorbent than that of O2 concentration.

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NEUTRONIC BENCHMARK ON HOLOS-QUAD MICRO-REACTOR CONCEPT

EPJ Web of Conferences ◽

10.1051/epjconf/202124701006 ◽

2021 ◽

Vol 247 ◽

pp. 01006

Author(s):

N. E. Stauff ◽

C. H. Lee ◽

P. Shriwise ◽

A. Wells ◽

C. Filippone

Keyword(s):

High Temperature ◽

Cell Model ◽

Unit Cell ◽

Power Modules ◽

Preliminary Version ◽

Full Power ◽

Micro Reactor ◽

High Temperature Gas ◽

Good Agreement ◽

Full Core

The Holos-Quad micro-reactor concept is proposed by HolosGen LLC for civilian applications to generate 22 MWt with a lifetime of approximately 8 effective full power years (EFPYs). The design is based on a very innovative high-temperature gas-cooled reactor concept using four Subcritical Power Modules (SPMs) that fit into one commercial 40-foot transport ISO container. Neutronics benchmarks were developed based on a preliminary version of the Holos-Quad design to confirm feasibility of the neutronics design of this non-traditional high temperature gas-cooled (HTGR)-type micro-reactor concept. Calculations were performed using Monte Carlo codes (SERPENT and OpenMC) as well as the PROTEUS high-fidelity deterministic code for two exercises based on a unit cell model and a full core model. The results obtained showed good agreement with all of the evaluated parameters for the unit cell problem and the full core problem. SERPENT and OpenMC display consistently good agreement in eigenvalue within 150 pcm for the unit cell benchmark and less than 270 pcm for the full core benchmark. PROTEUS eigenvalues showed relatively larger differences but still reasonable agreement with the SERPENT solutions. For the depletion benchmark, the observed eigenvalue differences between SERPENT and OpenMC were within 300 pcm throughout the depletion up to 100 GWd/MT, ensuring that the two codes used equivalent input parameters such as the recoverable heat values for fission reactions. This benchmark exercise confirms the neutronic feasibility and core performance of the preliminary Holos-Quad design.

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An Environmental Wet Cell For High Voltage Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070539 ◽

1973 ◽

Vol 31 ◽

pp. 18-19

Author(s):

N.J. Tighe ◽

H.M. Flower ◽

P.R. Swann

Keyword(s):

Electron Microscopy ◽

High Temperature ◽

Image Quality ◽

Inelastic Scattering ◽

High Voltage ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Environmental Cell ◽

Water Saturated ◽

High Temperature Gas

A differentially pumped environmental cell has been developed for use in the AEI EM7 million volt microscope. In the initial version the column of gas traversed by the beam was 5.5mm. This permited inclusion of a tilting hot stage in the cell for investigating high temperature gas-specimen reactions. In order to examine specimens in the wet state it was found that a pressure of approximately 400 torr of water saturated helium was needed around the specimen to prevent dehydration. Inelastic scattering by the water resulted in a sharp loss of image quality. Therefore a modified cell with an ‘airgap’ of only 1.5mm has been constructed. The shorter electron path through the gas permits examination of specimens at the necessary pressure of moist helium; the specimen can still be tilted about the side entry rod axis by ±7°C to obtain stereopairs.

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