Thursday, June 11, 2015

Ball Valves Used in Continued Catalyst Regeneration

severe service ball valve
Severe service ball valve
(courtesy of MOGAS)

Control of pressure within the platforming process affects the reformer yields, reactor temperature requirements and catalyst stability. Critical to the stabilization of the entire process are the lockhopper isolation, catalyst addition, reactor isolation and vent valves.

Safely Handling Hydrogen to Eliminate Hazardous Fires

The potential for hydrogen fires caused by external body or stem leaks is a significant concern. The continuous scratching of catalyst fines to any exposed seats or plugs could eventually allow dangerous leak-through-to-atmosphere resulting in H2 fires. Specify metal-seated, severe service ball valves that do not expose critical sealing components to the damaging effects of catalysts and provide the self-wiping ball and seat configuration that will clean away any built-up debris.

Continued Catalyst Regeneration
A catalytic reformer unit
in a petroleum refinery
(courtesy of Wikipedia)
Eliminating Catalyst & Dust Build-up

As the catalyst breaks down, harmful dust is produced. If catalyst dust migrates into the packing chamber of the valve, it can erode the stem packing, causing an external leak. A rising, rotational stem action can create areas for this build-up. With a quarter-turn, non-rising stem found in ball valves, this problem is eliminated.

Dependable Cycling Prevents Interruptions

A CCR unit is a timed process. Valves are expected to open and close at certain times to allow or stop the flow of catalyst. If a valve fails to operate, the process cannot perform and locks up. Additionally, if a valve is leaking enough to affect the pressure on the next lockhopper, the unit controls will not allow the process to move on to the next step. Quick, quarter-turn operation of severe service ball valves is the best solution for this situation.

Maintaining Design Integrity During Thermal Expansion

If the operating temperatures are elevated, or an upset in the process occurs, thermal expansion of valve components can cause concern. Carefully consider the material and coating selections, combined with the engineered geometry allowances of the ball valve, and ensure reliable and adequate protection against extreme heat variations.

As with any engineered product, it is always suggested you call in an applications expert before you specify, purchase, or install such critical service ball valves.