Materials for high temperature liquid lead storage for concentrated solar power (Csp) air tower systems

• Today the technical limit for solar towers is represented by the temperature that can be reached with current accumulation and exchange fluids (molten salts are generally adopted and the max temperatures are generally below 600◦ C), even if other solutions have been suggested that reach 800◦ C. An innovative solution based on liquid lead has been proposed in an ongoing experimental project named Nextower. The Nextower project aims to improve current technologies of the solar sector by transferring experience, originally consolidated in the field of nuclear plants, to accumulate heat at higher temperatures (T = 850–900◦ C) through the use of liquid lead heat exchangers. The adoption of molten lead as a heat exchange fluid poses important criticalities of both corrosion and creep resistance, due to the temperatures and structural stresses reached during service. Liquid lead corrosion issues and solutions in addition to creep-resistant material selection are discussed. The experimental activities focused on technical solutions adopted to overcome these problems in terms of the selected materials and technologies. Corrosion laboratory tests have been designed in order to verify if structural 800H steel coated with 6 mm of FeCrAl alloy layers are able to resist the liquid lead attack up to 900◦ C and for 1000 h or more. The metallographic results were obtained by mean of scanning electron microscopy with an energy dispersive microprobe confirm that the 800H steel shows no sign of corrosion after the completion of the tests. 

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Materialteknik -- Metallurgi och metalliska material (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering -- Metallurgy and Metallic Materials (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik -- Korrosionsteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering -- Corrosion Engineering (hsv//eng)

Keyword

Alloy 800H

FeCrAl alloys

Lead corrosion

Solar concentrated towers

Solar system

Aluminum alloys

Aluminum metallography

Chromium alloys

Chromium metallography

Creep

Creep resistance

Heat exchangers

Heat resistance

Iron alloys

Iron metallography

Liquids

Scanning electron microscopy

Solar power plants

Steel corrosion

Steel testing

Ternary alloys

Concentrated solar power

Experimental activities

Experimental projects

Heat exchange fluids

High-temperature liquids

Innovative solutions

Materials and technologies

Technical solutions

Corrosion resistant coatings

Publication and Content Type

ref (subject category)

art (subject category)