The purpose of filtration is the removal of suspended solids form water. Filtration is the process of passing water through a bed of granular or powdered medium or through a porous, fiberous medium such as paper, cloth, or synthetic membrane to remove the suspended particles. These solid particles may be finely divided sand, silt, solid organic matter such as plant debris, precipitated (not soluble) iron, algae, bacteria, and a host of other materials found in both surface and underground water supplies.
To understand how a mechanical filter works, a number of factors need to be taken into consideration such as:
- Pore size of filtering medium
- Total filtering area available
- Capacity of filter
- Quality of the water to be filtered
- Required flow rates
- Construction / design of filter
The degree to which a filter will remove these particles will depend upon the sizes of the participles to be removed and the pore size (porosity) of the filtering medium. Thus, the finer the filter medium, the more completely will solid particles be removed from the water, but also the higher will be the resistance to flow and thus, the higher the pressure drop. If the pores in the filter medium are small through, even bacteria will be filters form the water.
A filter will not be able to produce an adept adequate flow of filtered water unless the filtering surface is large enough. Thus the amount of filter area is a key factor to ensuring Proper flow rates as well as total capacity. Equally as important is the design and construction of the filter. If the filter is not designed so the medium is cleaned (back washed properly) , the pressure on the bed may force solid particles through the pores of the filter , or the filter bed may open large channels or “cracks” so that water passes directly through the unit without any effective filtration.
Selecting a filter must be done carefully. On one hand, it must be large enough to provide adequate water flow and filtration. On the other hand, it must be small enough to enable adequate cleaning by periodic backwashing at the available flow rates. The size of the opening in the filter medium, compared with the sizes of the solid particles to b filtered out, must be taken into consideration.
Types of Filters
- Granular Carbon Cartridges
- Inline Filter Cartridges
- Mineral Cartridges
- Polypropylene Cartridges
- Iron Removal Filters
Filtration is the process of removing suspended solids from water by passing the water through a permeable fabric of porous bed of materials. Groundwater is naturally filtered as it flows through porous layers of soil. However, surface water and groundwater under the influence of surface water is subject to contamination from many sources. Some contaminants pose a threat to human health, and filtration is one of the oldest and simplest methods of removing them. Filtration methods include slow and rapid sand filtration, diatomaceous earth filtration, direct filtration, packaged filtration, membrane filtration and cartridge filtration. Based on the results of water analysis Sarjanselects the filtration process to be used while designing the water treatment process. Multi Grade Filter (MGF), Activated Carbon Filter (ACF) & Iron Removal Filter (IRF) are most commonly manufactured filtration systems that Sarjanoffers to the customers.
Granular Media Filter
Granular media filter are most commonly used in residential and commercial water treatment for the reduction of suspended particles, turbidity, such as clay, mud and as a profiler for oxidized iron. Most surface waters contain small particles of suspended mud, clay, or, inorganics which can produce turbidity (cloudiness) in water. Well water supplies may contain turbidity due to particles of iron or manganese. In either case, turbidity must be removed by filtration to produce water which acceptable for drinking, cooking and laundry uses.
In industrial setting, filter aids, coagulation / flocculation (precipitation), and the use of fine porous granular media are used to reduce the turbidity and colloidal content of the water before it can be used used. Whereas, in residential and commercial setting, a simple Granular filter may be all that is needed
- De - chlorination of water for industrial / drinking water applications
- Removal of organic matter from water
- Residential and commercial water treatment for the reduction of suspended particles, turbidity, such as clay, mud and as a profiler for oxidized iron. Most surface water contains small particles of suspended mud, clay, or inorganics which can produce turbidity (cloudiness) in water. Well water supplies may contain turbidity due to particles of iron or manganese. In either case, turbidity must be removed by filtration to produce water which is acceptable for drinking, cooking and laundry uses.
- In industrial setting, filter aids, coagulation / flocculation (precipitation), and the use of fine porous granular media are used to reduce the turbidity and colloidal content of the water before it can be used. Whereas, in residential and commercial setting, a simple Granular Media filter may be all that is needed.
Iron Removal Filter (IRF) or Green Sand Filter
Both Iron & Manganese are essential nutrients for all life, and a typical daily dietary intake for humans is approximately 5 milligrams for each mineral. However EPA has established a limit for Fe & Mn that can be constantly achieved by SarjanIRF. The content of Fe & Mn are closely checked by our engineering department by testing the water, Later IRF is designed and manufactured to install in the system.
IRF are extremely useful for removing Ferrous Iron and Manganese. They are comprised of bed of natural or synthetic Manganese Green Sand. Manganese Dioxide oxidizes iron & manganese and the particles are available in FRP / MS vessels. Filter media comprises of Layers of Manganese Dioxide, Fine Sand, Coarse Sand, Pebbles and Gravel. Manganese Dioxide will require regeneration with a weak solution of Potassium Permanganate after its absorption ability is weakened. Ferric Iron will require back wash to remove them.
- Housing Flats
- Tea Garden
- Industries etc
- Sarjan Iron Removal Filters are manufactured using either FRP or mild steel pressure vessels for longer life and rust free operation.
- System is operated at varied velocity from 0. 5 m3/hr to 40 m3/hr to obtain required water quality. Sarjan IRFs are available with the options of individual ball / butterfly valve or multiport valve.
- These filters eliminate turbidity, suspended particles, colour, odour and iron that are present in raw water.
- Sarjan Iron Removal Filters are pre-assembled, factory tested, compact and are easy to install.
- They operate and maintain anti-corrosive FRP vessels or sturdy mild steel vessels, PVC piping & valves and SS 304 skid for mounting units system requires only water. Electrical and drain supply and can be installed in a day.
- Multi port control valve for easy operation of filtration and electrical controls with all interlocks well packed - filter media to provide required iron free water quality.
Multi Grade Filters (MGF)
Sarjan offers you their best quality MGF with high performance and reliability. Suspended matters like sand, silt, organic material, scale etc. can be removed with our system.
Cartridge Filters With Disposable Element
Cartridge filters do not represent an alternate filtration technology, but rather than an alternative means of packaging familiar filtration technology. A cartridge filter can be a deep bed filter, precoat filter, sorption bed, a sheet filter, or a membrane filter, depending on its intended use. This filtration device comes as a unit with housing and the cartridge element as a separate entity. The cartridge element can be easily removed and a new element quickly installed. Figure 7-1 Illustrates this system a multiple cartridge, industrial type system housed in cluster fashion in a stainless steel vessels.
Activated Carbon Filters
Activated carbon filters have several uses: taste and odor control, chlorine reduction, organic reduction and reduction of hazardous organic chemicals. These features are sometimes combined in a single application, but they have distinctly different objectives. The fact that they are different is something which must be kept in mind. While some active carbons are excellent for one application, they may not be suited for another. Although there are different uses for activated carbon (AC), the actual adsorption mechanism in general the same. The first portion of this chapter will discuss the adsorption mechanism in general as well as common media materials and media types such as powdered, granular, and block carbon, and the second part of the chapter will discuss the applications.
Sarjan ACF absorbs many dissolved organics and eliminates Chlorine or other halogens in water. Organic substances include Trihalomethanes (THM), Pesticides, Industrial solvents, Polychlorinated biphenyls (PCBs) and Polycyclic Aromatic Hydrocarbons (PAHs. These Organic chemicals are responsible for taste, odor & colour problems. And our ACF are designed to deal with such problems encountered in water Sarjan design & manufactures ACF those are able to absorb chemicals by holding them when water passes through Filter. Activated Carbon is highly porous material having high surface area for contaminant adsorption.
Sarjan ACF are available in FRP as well as MS vessels. The vessel is packed with media in order to make the filter complete.
Oxidizing filters describe POU / POE treatment technologies used mainly for the removal of iron, manganese, and hydrogen sulfide. The term oxidizing filter is a broad one and refers to processes which oxidize soluble forms of these species to insoluble forms either prior to or directly in the filter.
This chapter will discuss several other chemically reactive media used as oxidizing catalysts; namely, manganese greensand, manganese zeolite, and manganese coated pumicite. The chapter has been divided into two sections. The first part is a general description of oxidizing filters and the principles involved in their operation. The second part considers specific applications using oxidizing filters. In the applications section, removal of "the troublesome Trio"
- Hydrogen sulfide
With an oxidizing filter, will be discussed, While cation resins can be used to reduce iron and manganese in water supplies, they have limitations. The discussion here will be on oxidizing filters.
Additional information on the alternative process for the removal iron, manganese, and hydrogen sulfide can be found in chapter 6, water processing for home, farm & business, published by the water quality association.