Nepheline Sludge as a Feedstock for building

Materials Graduate Student: Alyona E. Kovyazina

Institute of High Technology Physics, TPUGraduate Advisor: Vasiliy A. Lotov, Prof., Doctor

Linguistic Advisor: Larisa V. Maletina, Ass. Prof., Ph.D.

Outline Nepheline Properties Aim Materials & Methods Results

Nepheline Properties

• 80-85% Belite• Chemical composition is similar to portland cement

Use as a filler in:• Ceramic• Binder• Glass productions

Nepheline sludge

Aim

Aim – production of the durable crystalline matrix of material based on

nepheline sludge

• Main components: - nepheline sludge - quartz sand• salt additives

Raw materials

Quartz sand

Sodium sulfateAluminum sulfateFerrous sulfate (II)

Methods• Medium-dry extrusion - ratio of main components – 70/30 - time of hardening – 14 days - moist conditions• Casting - ratio of main components – 50/50, 60/40, 70/30 - time of hardening – 14 days - air conditions• Hydrothermal treatment - ratio of main components – 50/50, 60/40, 70/30 - time of hydrothermal treatment – 3 hours - time of hardening – 1 day - air conditions

Compressive strength of samples, МPа

Results

compositionlimit of compressive strength, MPa

50:50 60:40 70:30

Na2SO4additive 2,11 3,15 4,72

Al2(SO4)3 additive 1,78 2,15 2,91

Compressive strength of casting samples, MPa

compositionlimit of compressive strength, MPa

50:50 60:40 70:30

Na2SO4additive 5,27 7,23 10,61

Al2(SO4)3additive 3,78 5,03 8,12

Compressive strength of samples after hydrothermal treatment, MPa

Further research

• Hardening condition• Hydrothermal treatment• Porous structure production

Thank you for your attention!