Greensand Plus™

GreensandPlus™ is a black filter media used for removing soluble iron, manganese, hydrogen sulfide, arsenic and radium from groundwater supplies.

Catalytic Oxidation (CO) operation is recommended in applications where iron removal is the main objective in well waters with or without the presence of manganese. This method involves the feeding of a predetermined amount of chlorine (CI2) or other strong oxidant directly to the raw water before the GreensandPlus™ Filter.

Chlorine should be fed at least 10-20 seconds upstream of the filter, or as far upstream of the filter as possible to insure adequate contact time. A free chlorine residual carried through the filter will maintain GreensandPlus™ in a continuously regenerated condition.

For operation using chlorine, the demand can be estimated as follows: 
mg/L Cl2 = (1 x mg/L Fe) + (3 x mg/L Mn) + (6x mg/L H2S) + (8 x mg/L NH3).

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Greensand Plus™ Brochure

FEATURES

  • The Manganese Dioxide-coated surface of GreensandPlus™ acts as a catalyst in the oxidation-reduction reaction of Iron and Manganese.
  • The silica sand core of GreensandPlus™ allows it to withstand waters that are low in silica, TDS, and hardness without breakdown.
  • GreensandPlus™ is effective at higher operating temperatures and higher differential pressures than standard manganese greensand. Tolerance to higher differential pressure can provide for longer run times between backwashes and a greater margin of safety.
  • Systems may be designed using either vertical or horizontal pressure filters, as well as gravity filters.
  • GreensandPlus™ is a proven technology for Iron, Manganese, Hydrogen Sulfide, Arsenic and Radium removal. Unlike other media, there is no need for extensive preconditioning of filter media or lengthy startup periods during which the required water quality may not be met.
  • GreensandPlus™ is an exact replacement for manganese greensand. It can be used in CO or IR applications and requires no changes in backwash rate or times or chemical feeds
  • GreensandPlus™ has the WQA Gold Seal Certification for compliance with NSF/ANSI 61. Packaging is available in 1/2 cubic foot bags or 1 metric ton (2,205 lbs) bulk sacks.

CERTIFIED TO
WQA Gold Seal Certification for compliance with NSF/ANSI 61

MADE IN THE USA

Greensand-Plus_Highlight
Physical Properties
Bulk Density88 lbs./cu. ft. net
Effective Size0.30 to 0.35 mm
Uniformity CoefficientLess than 1.60
Specific GravityApproximately 2.4
PorosityApproximately 0.45
Screen Grading18 X 60 mesh
ColorBlack
CONDITIONS FOR OPERATION
Water pH Range6.2-8.5
Raw waters having natural pH of 6.2 or above can be filtered through GreensandPlus™ without pH correction. Raw waters with a pH lower than 6.2 should be pH-corrected to 6.5- 6.8 before filtration. Additional alkali should be added following the filters if a pH higher than 6.5-6.8 is desired in the treated water. This prevents the possible adverse reaction and formation of a colloidal precipitate that sometimes occurs with iron and alkali at a pH above 6.8.
Maximum Water TemperatureNo limit
BedDual media: anthracite 15-18 in. and GreensandPlus 15-24 in.
Minimum Bed Depth15 inches of each media for dual media beds or 30 inches of GreensandPlus alone
Service Flow Rate2 – 12 gpm/sq. ft.
Extremely high concentrations of iron and manganese usually require lower flow rates for equivalent run lengths. Higher flow rates can be considered with very low concentrations of iron and manganese. For optimizing design parameters, pilot plant testing is recommended. The run length between backwashes can be estimated as follows: The run length for a water containing 1.7 mg/L iron and 0.3 mg/L manganese at a 4 gpm/sq. ft. service rate: 
Contaminant loading (1 x mg/L Fe) + (2 x mg/L Mn) = (1 x 1.7) + (2 x 0.3) = (2.3 mg/L or 2.3/17.1 = 0.13 grains/gal. (gpg) 
At 1,200 grains / sq. ft. loading ÷ 0.13 gpg = 9,230 gal./sq. ft. 
At 4 gpm / sq. ft. service rate 9,230/4 = 2,307 min. The backwash frequency is approximately every 32-38 hours of actual operation.
Backwash Flow RateMinimum 12 gpm/sq. ft. at 55ºF (see expansion chart) Sufficient rate using treated water to produce 40% bed expansion for 8 minutes or until wastewater is clear.
Capacity700-1200 grains of oxidized iron and manganese / sq.ft. of bed area based on oxidant demand and operation to iron break through or dp limitations.
Air/Water ScourOptional using 0.8-2.0 cfm/sq. ft. with a simultaneous treated water backwash at 4.0-4.5 gpm/sq. ft.
Raw Water RinseAt normal service flow rate for 3 minutes or until effluent is acceptable.