The ALTRON product sheet in brief: what the nozzle is made of, how it is fitted to a steel grid, and how long it lasts.
The orifice size is the design.
A nozzle that keeps it keeps the regenerator.
ALTRON air grid nozzles are ceramic FCC air distributor nozzles made of alumina bonded silicon carbide and set in a metal assembly that is welded in place of the existing steel nozzle. Blasch states a service life two to five times that of high alloy steel nozzles. This page summarizes the Blasch product sheet and what it means for the regenerator grid.
An eroded orifice does not only lose metal, it changes how much air goes where, and every nozzle next to it pays for that.
The air grid spreads combustion air evenly into the bed of spent catalyst. Even air supports stable fluidization, clean coke burn and low catalyst attrition. Each nozzle meters its share through an orifice of fixed size.
Steel nozzles erode under hot catalyst and flue gas. The orifice grows into a keyhole shape, the air jet hits the neighbors, and the grid loses its balance long before the campaign ends.
Material: ALTRON, an alumina bonded silicon carbide developed for the abrasion and corrosion in FCC units. Blasch also uses NITRON, a nitride bonded silicon carbide, for this service.
Assembly: ceramic and metal assemblies welded in place of the existing steel nozzles, so the grid hardware stays as it is. That leaves the turnaround crew free for other work in the unit.
Service life: two to five times longer than high alloy steel nozzles or other ceramics, according to the sheet. It names no plant or service period for this figure.
Effect named in the sheet: less downtime and lower catalyst loss.
Blasch casts nozzles as direct replacements for existing metal designs, so the orifice and outer dimensions follow your grid. The forming process holds tight tolerances without machining, see the Blasch net shape process.
The air grid is hard to reach between turnarounds. A nozzle that keeps its orifice through the campaign keeps the air distribution you designed for. The reasoning behind the material choice is in Hard Choices, and other ceramic parts for the unit are on ceramic nozzles.
The ceramic itself cannot be welded. It sits in a metal assembly, and that assembly is welded in place of the old nozzle.
No. The assemblies are made to replace the existing nozzles without changes to the grid.
The nozzle type, the orifice size, the outer dimensions and the number of nozzles. Drawings help but are not required.
Send the nozzle dimensions and how they look at the last inspection. A Blasch engineer proposes the material and the assembly.
