Oil Refinery Applications

Air Grid Nozzles

The excellent wear resistant properties of Technox® 2000 ideally lends itself to the highly erosive environments of the air grid within the FCCU. Traditionally, there has been a problem with the joint used to locate the ceramic in the steelwork of the air grid. As the two materials have different coefficients of thermal expansion the ceramics tend to come loose at elevated temperatures. Dynamic-Ceramic has patented a fixing method that holds the Technox piece firmly within a split metal collar at all temperatures. The metal collar is spot welded around the nozzle to ensure a snug fit. The whole assembly can then be mounted by welding the collar to the grid. The novel design ensures that the ceramic and steel remain in intimate contact throughout the temperature range. This design has been successfully used in several refineries and the nozzles are now entering their second campaign after being found to be in ‘excellent condition’ after four years service. The extended life of the nozzles reduces subsequent “Turnaround” costs and more importantly provides a more consistent fluidized bed for easier management.

Catalyst Withdrawal Tubes

These parts have lasted 10 times longer than a refractory liner in the same application. Technox® 2000 was chosen for its excellent wear resistance to high flow rates of catalyst material. In ASTM C-704 tests, Technox® 2000 components recorded a 0.25cc loss compared with a refractory figure around 3cc. The end result of the introduction of this part is a more controllable flow of catalyst through the discharge port and less wear damage to the local pipe and valve areas.

Other components within the FCCU, such as orifice plates and feed injectors made from Technox® 2000 have also had their performance and lifetimes increased. This is partly due to the high strength, high fracture toughness and wear resistance of Technox® 2000 ceramics.

Pumps and Valves

As well as providing excellent erosion resistance within the FCCU, Technox zirconia ceramics are also widely utilized within pump and valve applications around the refinery. Tests have proven materials like Technox® 3000 to be up to 18 times better than Tungsten Carbide 6% cobalt materials. As Technox ceramics are oxides with no vulnerable binder phase, they are virtually inert and therefore resistant to corrosion as well as attack by cavitation which erodes the binder in tungsten carbide based materials. Please see our Pump and Valve data sheet for further details.