Optimization of a seed and blanket thorium-uranium fuel cycle for pressurized water reactors

A heterogeneous LWR core design, which employs a thorium/uranium once through fuel cycle, is optimized for good economics, wide safety margins, minimal waste burden and high proliferation resistance. The focus is on the Whole Assembly Seed and Blanket (WASB) concept, in which the individual seed and blanket regions each occupy one full-size PWR assembly in a checkerboard core configuration. A Westinghouse 4-loop 1150 MWe PWR was selected as the reference plant design. The optimized heterogeneous core, after several iterations, employs 84 seed assemblies and 109 blanket assemblies. Each assembly has the characteristic 17x17 rod array. The seed fuel is composed of 20 w/o enriched annular UO2 pellets. Erbium is used in the fresh seed to help regulate local power peaking and reduce soluble boron concentrations. Erbium was evenly distributed into all pin central holes except for the peripheral pins and four corner pins of each assembly where more erbium was used due to their higher power level. The blanket fuel is a mixture of 87% ThO2 - 13% UO2 by volume, where the uranium is enriched to 10 w/o. The blanket fuel pin diameter is larger than the seed fuel pin diameter. There are two separate fuel management flows: a standard three-batch scheme is adopted for the seed (18 month cycle length) and a single-batch for the blanket, which is to stay in the core for up to 9 seed cycles. The WASB core design was analyzed by well known tools in the nuclear industry. The neutronic analysis was performed using the Studsvik Core Management System (CMS), which consists of three codes: CASMO-4, TABLES-3 and SIMULATE-3. Thermal-hydraulic analysis was performed using EPRI's VIPRE-01.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Nuclear Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2003

Author dc:creator

• Wang, Dean, 1971-

Advisor dc:contributor.advisor

• Mujid S. Kazimi and Michael J. Driscoll.

• Nuclear Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/29956

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/29956