1.MATERIAL / particle characterization Understanding type and particle size is filtered allows you to select the correct size of micron filter. For example, well water contains inorganic particulates, such as sand, or where the pond surface water contains mainly organic substances such as algae and leaves. Generally, inorganic materials require a smaller screen to trap sediment and sand, which otherwise would have passed through the most. Water is only one example. You can also filter viscous products such as paper coatings, paints, honey, and everything in between. 2.MAXIMUM worker thread The flow rate determines the size of the filter you need. For example, a 2 “filter that accommodates the flow of 100 gpm will not work for a system operating at a rate of 150 gallons per minute. If that were the case, and you’ve worked with a maximum flow rate of 150 gallons per minute, then you should choose a filter one size more * Note: if you use a backwash filter, minimum flow should be considered in addition to the maximum flow. 3.Minimum and the maximum operating pressure Each filter is designed for a maximum pressure of work; Therefore it is very important to have an accurate measurement of the maximum pressure when setting the size and choice of filter. The minimum operating pressure is not a requirement for all types of filters, but it is very important when using the automatic self-cleaning filter for your application. When flushing the filter mechanism is engaged, the minimum operating pressure must be maintained. 4.PRESSURE DROP The pressure drop refers to a decrease in fluid pressure through a pipeline component, such as a filter. Since the liquid is forced through the filter material which removes contaminants, it changes direction several times. This action causes a certain amount of resistance to fluid flow, which leads to a lower pressure after the fluid passes through the filter. Several factors contribute to the pressure drop such as the filter material, the contaminants present, flow rate and viscosity. Why you should care about the pressure drop? As the bag filter or strainer begins to fill, the pressure drop increases as the filter of the filtered debris reduces the surface area. Once a point is reached where the pressure is to overcome this is too large, the desired flow through the filter will be disturbed. The size of the filter surface area and particle loading will be filtered to determine the frequency needs to be emptied. If the pressure drop is too high to begin with, the filter reaches the point of no return very quickly and clog. 5.OPERATING COSTS Automatic, self-cleaning filters, as is known, the higher initial investment compared to the manual and strainers. Given the choice between automatic and manual filtering, or simply slecting filtering material in general, consider the following criteria related to the cost of: (1) Labour costs and downtime for replacement of the cartridge filter or (2) The costs of manual labor when it comes to cleaning the mesh filter or other filter media (3) on waste disposal costs 6.OPERATOR RISK environmental impact Some filter media are suitable for highly toxic fluids where others are not. You must determine whether the operator and the impact on the environment in the liquid is acceptable or not, if you look filter.