The Zyme-Flow® Vapour-Phase Process is the newest and most frequently used application method, allowing for the quickest possible entry into process equipment. With the Vapour-Phase Process, Zyme-Flow UN657 is injected into the steam during a normal steamout. Steam carries the Zyme-Flow throughout the vessels or unit, contacting all surfaces and providing uniform decontamination of the process equipment.

The need for costly temporary circulation pumps and the amount of waste generated are greatly reduced. The Zyme-Flow Vapour-Phase Process consistently reduces steamout time by up to 75%. It reduces iron sulfide, benzene and LEL to the same levels as with the circulation process.

Boil-Out Process

The boil-out process is used most often with horizontal vessels, especially those in which a large volume of sludge is anticipated. In this process, water is added to the 30-50% level, followed by the addition of Zyme-Flow UN657 and steam. The steam provides both agitation and heat, raising the water temperature to 180°F - 220°F. The vapor carries overhead, decontaminating the upper area of the vessel as well. After the boil-out procedure, water is drained and the residual scale and debris is hosed out or swept out. Residual decontaminated sludge, scale and debris that has been contacted by Zyme-Flow UN657 will generally flow or move easily.

Circulation Decontamination Process

The basic process for vessel and piping decontamination involves an aqueous solution of Zyme-Flow UN657 that is circulated at a targeted temperature through all equipment and piping. The primary goals of this procedure are to reduce benzene to less than 1 ppm, H₂S to near zero and LEL to near zero.

The secondary goals of this procedure are to remove oils and sludges from both equipment and piping. This is done by wetting the solids and walls and by emulsifying the oil and sludges so that they can be removed from the system and recovered with the water phase.