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PROCESS

The Quest for Quality Sand

Years of research and development have enabled Galaxies(India) to deliver effective sizes and uniformity coefficients to meet or exceed the standards of consulting engineers and those recommended by the Indian Standard of Water Works

.Being Pioneer also assures that our customers receive top quality media. Quality control procedures, including complete laboratory analysis, are performed carefully and thoroughly to provide the finest sand available. From single bag orders to multiple carloads, Galaxies(India) promptly meets specific needs with tolerances from .25mm to 2.5mm.

Galaxies (India) filter sand is hard, not smooth, and free of soluble particles, To assure this chemical quality, Galaxies (India) incorporates the most modern equipment for washing drying, screening, and testing.

How Does Sand Filter?

The upper stratum
-Sand is an extremely effective filtering medium because of its ability to hold back coagulum or precipitates containing impurities. Because the upper stratum of the sand bed performs this filtering function, size and quality are of paramount importance

The lower strata
The lower strata of gravel acts to support the filtering stratum. For maximum efficiency, the supporting gravel must be properly graded to sizes calculated to support the filter sand

UPGRADATATION OF FILTER BED
Q	What benefits can you expect from converting our filters from Single-Sand to a Dual-Media (Sand and Anthracite ) System ?
A	The angularity of the anthracite results in a large void ratio and allows more solids holding capacity than the most rounded sand ~ yielding a consistently better filtrate quality throughout a filter run. The Dual-Media System more fully utilizes the entire bed for storage of filtered solids since water passing through a Dual-Media contacts the coarser anthracite offering ample void area to effect removal and storage of the suspended solids. The Dual-Media System also requires a lower backwash rate to achieve fluidization with filtration rates of 3-4 times higher than those of rapid sand filters.
Q	What additional benefits can we expect from using a uniformity coefficient of <1.3 on our Filter Anthracite in the Dual-Media System ?
A	The lower uniformity coefficient anthracite has less oversized and undersized particles resulting in a very uniform bed. The low uniformity coefficient anthracite coal requires much lower backwash rates, which results in substantial savings to the owner due to the reduced monthly/annual wash water requirements.
Q	How can we determine when we need to replace our Media System ?
A	Depending upon many factors including the operation and maintenance of filter components, the Media System typically needs replaced every 15-20 years. Media has a tendency to round-off from attrition and lose its effectiveness. The media also can increase in size due to agglomeration of chemicals and polymers attaching the media. Galaxies(India). can provide filter evaluations to determine the solutions to Filter Maintenance needs.

ADVANTAGES OF DUAL MEDIA

Dual Media with can provide many benefits in granular beds filter.
These benefits include.
Increased plant capacity by the use of higher filtration rates.
Lower backwash rates in mono, dual- and tri-media filters.
Better production efficiency due to longer filter cycles at higher filtration rates.
Our anthracite filter media meets and exceeds ISI.
Listed/Certified International Standard 61 - Process Media.