Specifications of manganese greensand.
PHYSICAL CHARACTERISTICS
Physical Form Black, nodular granules shipped in a dry form
Apparent density 85 pounds per cubic foot net
Shipping weight. 87 pounds per cubic foot net
Specific gravity. Approximately 2.4
Screen grading (dry). 18 x 60 mesh
Effective size 0.30 to 0.35 mm
Uniformity coefficient. Less than 1.60
pH range 6.2 to 8.5
Maximum temperature. Above 80ºF, contact manufacturer
Maximum pressure drop 8 to 10 psi
Backwash rate Minimum 12 gpm/ft.2 at 55ºF
Service flow rate. 2 to 5 pgm/ft.2
Minimum bed depth. 24 inches (15 - 18 inches of each media for dual media beds)
A visual examination of a dried sample of Manganese Greensand is usually sufficient to determine whether or not the sample is suitable for use.
Under a microscope the media should appear to be dark and purplish black in color. If it is reddish or reddish brown that means that it has been oxidized. If it appears to be green it means that the coating of Manganese has been stripped from the media. If the media has been oxidized or stripped it can be considered spent.
The mesh size of the grains should be between 16 and 50 standard U.S. screen.
The sampling procedure for the Manganese Greensand is similar to that used for ion exchange resins. The sample should be representative of the entire bed after backwashing. That is, a composite sample should be taken, ideally with core tube sampler.