"AquaTherm" Multigrade Sand filter / Pressure quartz is latest concept in the field of filtration technology media filtration to generate water free from suspended solids ( TSS < 5 ppm) . The suspended solids are trapped by using fine pure graded silex/ quartz as the filter media .The quantity of filter media and vessel size is designed to handle incoming suspended solid upto 50 ppm. The Activated Carbon Filter is widely used to remove colour,odour and chlorine from the water.It consists of Activated Carbon granules with higher iodine value and as per IS 877 standards is used for Filtration, supported by layer of graded sand. In order to remove dissolved Iron and for fine filtration specially designed filter can be supplied . In case of excess suspended solids and turbid particles Plate type clarifier can be incorporated.

Multigrade Sand Filter Plant

Technical Features

• Cylindrical Mild steel / FRP pressure vessels with dished ends.
• Mild Steel pressure vessel are painted internally with anticorrosive paint and externally with a protective coat of red oxide primer & Enamel
• Internal water distribution & collection system.
• Initial charge of filter sand & underbed material
• Frontal pipe work & valves.
• Pressure gauges to monitor head loss across the filter.
• Multigrade sand filters , Activated Carbon Filter / Iron Removal Filters are available from 600 to 3000mm diameter
• Mild Steel Welded Pressure Vessel fitted with M. S. Frontal pipe & C.I. diaphragm valve, strainers, sampling cock, pressure gauge, air compressor and first charge filter media.
• FRP pressure vessel, fitted with plastic internal fittings. Set of CPVC frontal piping, linking multi-port valve/CPVC ball valves to FRP vessel.
• FRP vessel is Light weight equipment.& Easy to install - does not require concrete foundation.
• Offered Capacity : 1.0 m3/hr to 100.0 m3/hr. water flowrates

Activated Carbon Filter Plant

Multigrade filter is a depth filter that makes use of coarse and fine media mixed together in a fixed proportion. This arrangement produces a filter bed with adequate pore . dimensions for retaining both large and small suspended particles. This filter performs at a substantially higher specific flow rate than conventional filters. Specific flow rates of 15 – 30 m/h have been successfully obtained for treating waters containing 25 – 50 ppm suspended solids respectively to produce filtrate with less than 5 ppm. This filter performs at a substantially higher specific flow rate than conventional filters. The basic difference between Pressure Sand Filter (PSF) and Multigrade Sand Filter (MGF) are media used in vessel and velocity variation.

A typical pressure sand filter consists of a pressure vessel-this could be either vertical or horizontal-fitted with a set of frontal pipe work and valves, graded sand supported by layers of graded under bed consisting of pebbles and silex, a top distributor to distribute the incoming water uniformly throughout the cross section of the filter, and an under drain system to collect filtered water

Anthracite Filter Media is thoroughly selected from anthracite which yields the highest percentage of carbon. It is then hydraulically classified to reduce mineral matter and ash to a minimum, and finally screened and washed to ensure suitability for filtration purposes.

Activated carbon filter media aggressively adsorbs organic pollutants from water & waste water, detoxifies harmful gases and removes unwanted colors or odors from your water. The coconut shell based Activated carbon media removes colour,odour and dissolved chlorine from water. Specific flow rates of 15 – 30 m/h have been successfully obtained for treating waters containing 1 – 5 ppm load.

Iron Removal Filter

This is the filter to remove dissolved Iron from the water.Greensand filters are typically designed to flow at 3-5 gpm per square foot of filter surface area and need a minimum of 12 gpm per square foot for backwash. Backwash should be initiated manually or by pressure differential switch when the differential pressure across the filter increases by 12 psi. Excessive delta P can damage the media

Chemical Pretreatment Filtration with manganese greensand often requires pretreatment with an oxidizing agent. On small commercial or residential systems, this may be accomplished by oxygen in the air using a small air pump and a contact tank upstream of the greensand filter. In large flows, it is typically accomplished with chlorine and / or potassium permanganate, a strong oxidizer. Because the oxidation reaction required to convert the soluble material into solid particles, followed by successful filtration must be accomplished in 1-2 minutes of filter residence time, the water chemistry must be conducive to rapid reaction kinetics. Technical literature typically recommends pH in the 6.2 to 6.5 range. Alkalinity must be ? 120 ppm. These parameters can be adjusted by metering a dilute caustic and / or a soda ash solution into the water upstream of the filter to adjust pH and alkalinity, respectively. For iron alone, chlorine fed at a concentration of 1.0 to 1.2 times the iron should be adequate to oxidize the iron and “regenerate” the manganese greensand.

Advantages Filter Plant are

• Higher specific flow rate than conventional down flow filters thereby saving on Space & cost.
• Very little maintenance required.
• Lower backwash water requirement.
• In most cases, raw water can be used for backwash.
• Less space required as operating specific flow rate is higher than conventional filters.
• Ease in maintenance.
• Lower backwash water requirement hence saving in cost.

• Removes Colour & Odour
• Removes dissolved chlorine and hence useful in Ion exchange Resin based softner / DM & RO plant treatment to protect it from oxidation.
• Ideal for pretreatment and waste water treatment.

• Remove Yellow stains from clothes.
• Prevents bacteria and stomach /gastric disorder.
• Prevents corrosion & clogging of pipe line.
• Keeps Bathrooms / kitchens clear.

Limitations of Filter Plant are:

• Handles inlet suspended solids load upto certain extent
• Handles inlet load of dissolved organics and chlorine upto certain extent.
• Needs chemical pretreatment to enhance the filtration efficiency.

Applications: