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Treating penetrant wastewater, without filters

Oct. 9, 2009
Small-footprint system uses ozone to treat fluorescent penetrant rinse water by removing the coloration.
The MagnaPure II penetrant wastewater removal system.

The cost and time constraints of replacing filters and cartridges when treating wastewater can be quite an undertaking. To treat penetrant wastewater, processors face the costs filters and cartridges, as well as disposal issues.

In order to ensure the structural quality of castings (and other parts, too), many buyers require a nondestructive testing method in which a penetrating liquid is applied to the surface. After a short time, a second liquid is applied to draw out the penetrant out — which reveals the location and condition of the surface defects.

Penetrants are formulated according to the material they test: they must spread easily; be drawn by capillary action into the surface of the object; remain in the defect, and yet fluid (in order to be drawn out again.)

Next, a “developer” fluid is applied to the surface to draw out the penetrant trapped in the defective areas, so that they will make the flaws visible. Developers may be in powdered or liquid form.

Among the types of defects that may be discovered this way are fatigue cracks, quench cracks, grinding cracks, overload and impact fractures, and porosity.

The penetrants can be removed in different ways, but the simplest way is to wash the product clean with water. Water-soluble penetrants contain an emulsifier, and these materials form gels that may temporarily cling to surface defects. Whatever formulation is used, handling the wastewater presents a new challenge to the inspection process.

This treating, transporting, and disposing of penetrant wastewater can be a time consuming and costly process for manufacturers and test facilities involved with NDT inspection processes. As federal, state, and local environmental restrictions grow tighter, disposing of non pre-treated wastewater has come with a high price.

Magnaflux has introduced the MagnaPure II, a “next generation” penetrant wastewater removal system. It uses ozone to treat fluorescent penetrant rinse water by removing the green dye color.

The MagnaPure II eliminates the fluorescent color and odor that is objectionable to many waste-treatment facilities. The filterless system uses ozone to automatically remove dye penetrant color and odor from the wastewater, so drain disposal is permissible in most communities. A separate sample valve does not interrupt the treatment process. And, unlike other filtration equipment, the process leaves no sludge or residue for further disposal.

Not only is the system effective, it is compact. It measures 62 32 42 in., and yet processes up to 500 gallons/ day (estimate based on concentrations of 1,000 ppm), making it a good fit for manufacturers and test labs seeking to reduce capital costs. There are no filters to purchase, maintain, or dispose. And, the system is installed in conjunction with the penetrant rinse station.

Maintenance is minimal, according to Magnaflux, which also saves costs. And, the developer will provide “drop-in installation,” if needed.