Inert Alumina Ceramic Balls for Catalyst Support and Tower Packing

Inert alumina ceramic balls support and protect a bed of catalyst or packing in a reactor or column. They are laid at the bottom of the vessel to hold the catalyst up and spread the incoming gas or liquid evenly across the bed, and often over the top to hold the bed down and stop it being disturbed. Because they are inert, they take no part in the process; they carry the load, distribute the flow and protect the catalyst. They also serve as heat-storage media in thermal oxidisers and as bed support in drying and gas-purification columns.

The grade is set by alumina content and follows the temperature, the load and the chemistry. Low-alumina balls are the economical choice for ordinary support duty; medium-alumina balls take more heat and load; and high-alumina balls, above ninety percent alumina, are used where the temperature is highest, the bed is tallest, or the strongest acid resistance is needed. A higher alumina content buys more strength, more heat resistance and lower impurity pickup, at a higher price, so the grade is matched to the service.

Support balls are graded by size through the bed: coarse balls go at the very bottom to carry the load and pass the flow, with progressively finer balls above them, up to a size just larger than the catalyst so it cannot fall through. Sizes run from 3 millimetres up to 50 millimetres, and a typical support layer uses two or three sizes in steps. Tell us the catalyst size, the vessel and the flow, and we will work out the grading and the quantities.

Yes. These balls are highly resistant to acids and take alkalis well, and they hold up to continuous high temperature — up to around 1200 degrees for the higher grades — without softening or reacting. That chemical and thermal stability, together with a high crush strength, is exactly why inert ceramic balls are used to carry a catalyst bed in hot, aggressive process conditions where a lesser material would break down.

They are different products for different jobs. Inert ceramic balls are support media — larger, chemically inert spheres that hold up and protect a catalyst or packing bed and take no part in grinding. Grinding media, such as alumina or zirconia beads, are denser, harder and usually smaller, and their job is to grind and disperse a material in a mill. This product is support media; for grinding we supply separate alumina and zirconia grinding beads.