Development of an advanced ('700°C') PF power plant

• Research unit: EU RFP
• Project number: 97.0193-1

Key words (English)

Steam power plant; turbine; boiler; efficiency; thermie; high temperature; superalloys; creep strength

Alternative project number (English)

EU project number: SF/1001/97

Research programs (English)

EU-programme: 4. Frame Research Programme - 5.1 Nonnuclear energies

Short description (English)

See abstract

Partners and International Organizations (English)

Coordinator: ELSAM (DK)

Abstract (English)

During this year activities in the first phase of the project and the second phase are running concurrently.
Activities of ALSTOM in Baden in the first phase have concentrated on
- longterm mechanical testing of nickel-based materials,
- development of welding and nondestructive testing procedures for rotor fabrication and
- mechanical integrity validation of the steam turbine.
Longterm mechanical testing: Candidate nickel based alloys for major components such as rotors, casings, blades and bolts are being subjected to testing to determine the creep, low cycle and toughness properties required for design and construction of turbines and valves. The final selection and validation of materials should be completed in 2004.
Welding and nondestructive testing of dissimilar welds: Welds are required between the selected nickel-based alloys and high alloyed steels in particular for the fabrication of welded rotors. Pretests of weldability have been aimed at permitting a selection of the welding technique, weld metal and appropriate post weld heat treatment. Candidate techniques include submerged arc and TIG welding and weld metals are either of nickel-based or 10%Cr steel type. Weld metals differ basically in terms of freedom from defects and in defect tolerance (requiring high toughness). Welds have been manufactured and subjected to ultrasonic testing. Welding defects are only very small and detection techniques are satisfactory.
Steam turbine mechanical integrity: Design activities have been performed for all major high temperature components of a single-reheat 400MW high efficiency power plant to verify that loading levels are acceptable. Dimensions of the components have been determined and loading factors lie in the usual range.
In addition basic design has been performed for a demonstration facility. This is an existing power plant in which components from the project will be testing on the full scale. The plant will be fitted with additional superheaters to raise steam temperature to 700°C and the steam will drive an additional steam turbine, which is supplied by ALSTOM and which will also operate at 700°C.
Cost estimates have been made for the additional boiler and turbine sections. The costs and efficiency values will be used to verify the economic viability of the Thermie Concept.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 97.0193-1