Shivam Water Treaters Pvt. Ltd.

PROCESS

The filter is equipped with certain valves and devices which are incorporated in the outlet – pipe system. The purpose of these devices is to maintain a constant rate of filtration. An important component of the regulation system is the “ Venturi meter” which measures the bed resistance or “loss of head”. When the resistance builds up, the operator opens the regulating valve so as to maintain a steady rate of filtration. When the “ loss of head” exceeds 1.3 meter it is uneconomical to run the filter.
Normally the filter may run for weeks or even months without cleaning. When the bed resistance increases to such an extent that the regulating valve has to be kept fully open, it is time to clean the filter bed, since any further increase in resistance is bound to reduce the filtration rate. At this stage, the supernatant water is drained off, and the sand bed is cleaned by “ scraping” off the top portion of the sand layer to a depth of 1 or 2 cm. This operation may be carried out by unskilled laborers using hand tools or by mechanical equipment. After several years of operation, and say 20 or 30 scrapings, the thickness of the sand bed will have reduced to about 0.5 to 0.8 meter. Then the plant is closed down and a new bed is constructed.

Pressure sand filters are made in two types. Vertical ad Horizontal. The principles of operation and method of working are similar and available in different size and capacities. SWT filters are very efficient to reduce the suspended solids. The different type of filtering media like Gravel, Silex, work as sand rest bed. In both filter water admitted at the top and passed away from the filter. The incoming water is directed on a baffle to prevent disturbance of the sand .

Scope Of Supply

Main Pressure Vessel of S.S. / M.S. / F.R.P. provided with stainer plates at top and bottom, & internally protected with plastic paint to prevent corrosion . Set of frontal piping & valves to control the Inlet,Outlet, Wash Out, Wash Out, Drain and Air supply for backard. One charge of filtering media/ Activated Carbon of required quality and sizes along with unit. The carbon filter will have steam-bath reactivation arrangement.

Application

Rapid sand filter can deal with raw water directly. No preliminary storage is needed
The filter beds occupy less space
Filtration is rapid, 40-50 times that of a slow sand filter
The washing of the filter is easy
There is more flexibility in operation.

Comparison Of Rapid And Slow Sand Filters
Sr. No.	Particulars	Rapid sand Mechanical filter	Slow sand filter
1	Space Occupies	very little space	large area
2	Rate of filtration	200 m.g.a.d.	2-3 m.g.a.d.
3	Effective size of sand	0.4-0.7 mm	0.2-0.3 mm
4	Preliminary treatment	Chemical coagulation and sedimentation	Plain sedimentation
5	Washing	By back-washing	By scraping the sand bed
6	Operation	Highly skilled	Less skilled
7	Loss of head allowed	6-8 feet	4 feet
8	Removal of turbidity	Good	Good
9	Removal of colour	Good	Fair
10	Removal of bacteria	98-99 per cent	99.90 to 99.99 per cent

Our Other Models

Model No.	Diameter of Unit in mm.	Size of Piping in mm.	Flow Rate M3/hr.	Qty. of Activated Carbon
PSF – 3	300	20 MM	1.2	25 Kgs.
PSF – 4	400	25 MM	2.1	40 Kgs.
PSF – 5	500	25 MM	3.4	65 Kgs.
PSF – 6	600	40 MM	5.0	90 Kgs.
PSF – 7	700	40 MM	6.6	125 Kgs.
PSF – 8	800	50 MM	8.6	165 Kgs.
PSF – 9	900	50 MM	11.3	210 Kgs.
PSF – 10	1000	50 MM	13.5	260 Kgs.
PSF – 11	1100	50 MM	16.3	310 Kgs.
PSF – 12	1200	60 MM	20.0	375 Kgs.
PSF – 13	1300	60 MM	22.8	650 Kgs.
PSF – 14	1400	80 MM	26.5	500 Kgs.
PSF – 15	1500	80 MM	31.5	580 Kgs.
PSF – 16	1600	100 MM	34.5	650 Kgs.
PSF – 17	1700	100 MM	39.0	750 Kgs.
PSF – 18	1800	100 MM	45.0	840 Kgs.
PSF – 19	1900	100 MM	48.7	935 Kgs.
PSF – 20	2000	100 MM	54.0	1000 Kgs.