Combustion chamber hot face refractory lining
A method for producing a refractory lining in a combustion chamber operating in a reducing atmosphere. The lining includes at least one or more Zirconia (Zr)-based refractory lining members comprising one or more Zr-based parts. The Zr-based parts comprise at least 90 wt. %, preferably at least 95 wt. %, of monoclinic ZrO 2 and/or partially stabilized ZrO 2 and/or fully stabilized ZrO 2 , wherein the total content of tetragonal and cubic ZrO 2 amounts to at least 20 wt. %, preferably more than 35 wt. %, as well as Zr based refractory lining members and methods for manufacturing the Zr based refractory lining members.
1. A method for producing a shaped and fired zirconia refractory material in form of coating layer on an alumina based refractory material, the method comprising the steps of:
a) providing a shaped refractory of an Al 2 O 3 -based refractory material, optionally with a corresponding cleaning of the surface to be coated,
b) applying a powder dispersion comprising granular stabilized fused ZrO 2 raw material powder in form of a conditioned carrier fluid onto at least one surfaces of the shaped AI 2 O 3 based refractory material, and
c) drying the applied power dispersion followed by a thermal treatment at a temperature above 1200° C., thereby obtaining a bonded coating, the bonded coating layer comprises a total content of tetragonal and cubic ZrO 2 measured by X-ray powder diffraction analysis of at least 20% by weight, and wherein the Al 2 O 3 content is 0.05-6% by weight, and wherein the SiO 2 content of bonding phase of the material is below 1.5% by weight.
2. A method for producing shaped and fired zirconia refractory material in form of coating layer according to claim 1 , wherein the powder dispersion is applied by way of techniques within the group: spraying, painting, dipping and casting.
3. The method of claim 1 , wherein the powder dispersion has a viscosity of 2000-6000 mPa·sec.
4. The method according to claim 1 , wherein the powder dispersion comprising the stabilized fused ZrO 2 raw material powder presents an average grain size in the range of approximately 2.5 μm to 50 μm.