2025 Nelsen Corporation Catalog - Catalog - Page 119
Filter Sand & Gravel 4
Filter Sand & Gravel
Physical Properties (Filter Sand):
Parameter Description ........Physical Form Light brown, sub-angular/sub-round
Bulk Density .................................................... ~ 100 lbs. per cubic foot
Hardness .............................................................(Mohs Scale) 6.0 - 7.0
Effective Size Range ......................0.20 - 0.30 mm to 2.00 - 3.00 mm
Uniformity Coefficient ...............................................1.3 to less than 1.7
Acid Solubility ...............................................................................< 1.0%
Specific Gravity .............................................................................. > 2.6
Silicon Dioxide Content................................................................ > 85%
Loss on Ignition ........................................................................... < 2.0%
Conditions for Operation (Filter Sand):
Bed Depth .............................................................................. 18 - 30 in.
Backwash Rate............................................................... 15 - 20 gpm/ft2
Backwash Bed Expansion ......................................... 35% of bed depth
Service Flow Rate
Municipal ....................................................................... 1.5 - 2 gpm/ft2
Industrial ............................................................................... 3 gpm/ft2
Domestic ............................................................................... 5 gpm/ft2
Advantages:
• Highly-spherical shape and uniform grading provides reliable
performance in this product with a long history of performance.
• Low soluble impurities prevent undesirable mineral leaching into
process stream.
Certified to
NSF/ANSI 61
Filter Sand
FILSAND
Sand filtration continues to make good sense: its cost-to-benefit ratio is very high, and effluent water
quality is often very good. Sand systems can filter to a 10 micron level, yet they are simple in design
and operation. River washed .44 to .55 mm sand with a high silica content, low impurities and a highly
sperical shape for municipal, industrial and residential filter applications.
Pallet quantity - 56 bags per pallet
FILSAND
1/2 Cubic Foot Bag (50 lb)
FILSAND-50-BOX
1/2 Cubic Foot Box (50 lb)
Gravel
GRAVEL 20
GRAVEL 14
GRAVEL 12
Red Flint gravel offers extremely high pure silica content (>99% SiO2). All gravels are washed, kiln dried
for smaller sizes, and screened to meet EXACTING specifications. Red Flint’s Gravel Media is composed
of sub-angular, hard, durable, and dense grains of predominantly siliceous material. Extracted from
a clean glacial sand deposit, Red Flint Sand & Gravel’s physical properties make it among the finest
Sand Medias available in the world for filtration applications. All gravel varieties meet American Water
Works Association B100 Specifications for Granular Filter Media and are NSF certified for Standard 61 –
Drinking Water System Components & Materials.
Pallet quantity - 56 bags per pallet
GRAVEL14
1/4" x 1/8", 1/2 C.F Bag
GRAVEL14-50-BOX
1/2 Cubic Foot Box (50 lb)
GRAVEL14-20-BOX
1/5 Cubic Foot Box (20 lb)
GRAVEL12
GRAVEL12-50-BOX
1/2" x 1/4", 1/2 C.F Bag
1/2 Cubic Foot Box (50 lb)
GRAVEL20
GRAVEL20-50-BOX
#20 Flint, 1/2 C.F Bag
1/2 Cubic Foot Box (50 lb)
Call Nelsen Toll-Free from Anywhere in the U.S. - 800.362.9686
All prices and products subject to change without notice. ©Nelsen Corporation
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Resins, Media & Chemicals
Since 1917, Red Flint Sand and Gravel, has produced the highest
quality water filtration media and specialty aggregates available
worldwide. Red Flint manufactures products with precise effective
size ranges and the lowest uniformity coefficients in the industry.
The sand and gravel meets or exceeds the AWWA B100 Standard
and is NSF/ANSI Standard 61 & 372 certified for quality and purity.
Red Flint Silica Sand is graded specifically for use in water and
waste water filtration processes. Filter sand can be used in
municipal, industrial, or residential applications. The low acid
solubility and high silica content of our filter sand ensures durable
and long lasting filter media performance.
Red Flint Gravel is manufactured to be uniform in size which
promotes excellent flow and even distribution in support beds.
Gravel is low in soluble impurities and maintains its quality as a
support bed for the filter media.
