The success of micro irrigation depends on the ability of the system to prevent emitter clogging. Emitters with small orifices are used to deliver the required low flow rates and these small orifices can easily be clogged by particulate matter, biological growths, chemical precipitates or combination of these present in irrigation water. Clogged or partially clogged emitters reduce the uniformity of water and nutrient application, thus reducing the uniformity of plant growth and the yield. A properly designed micro irrigation system must have provisions to prevent emitter clogging. These provisions may include water quality analysis to identify the severity of the clogging problem, physical control of water by a filtration system and aeration/settling ponds, chemical treatment and biological control of irrigation water. Of which, physical control of water is mostly practiced to remove sand, silt and clay particles from irrigation water. The particles larger than about 1/10th of the size of the emitter orifice or flow passage should be removed using a proper filtration system to prevent particles from jamming. Without their removal, materials will settle out and deposit as sediments where the water velocity is low and causes emitter plugging.
Causes of Clogging
Most common reason of the obstruction is about mineral, organic and inorganic materials found in the water source.
Because drip-irrigation water must pass through the emitters, the size of the particles in the water must be smaller than the size of the emitter to prevent clogging
Process of filtering water in the irrigation system is referred as filtration.
Filtration is the best protection method against avoiding entrance /obstruction of drippers, sprinklers and other similar equipment’s used in the irrigation systems.
Emitter clogging can be attributed to:
Physical (includes sand , silt ,plastic chips and metallic flakes)
Chemical (precipitation of iron and salt, such as calcium carbonate, and precipitation of fertilizers in the lateral and the emitters.)
Biological (growth of algae in the water source and, at times, in the drippers, and/or growth of bacterial slime in the system and bacterial precipitation of sulfur or iron.)
The amount of filtration you need is dependent to a large degree on what type of irrigation you have. For example, drip irrigation systems need a much higher degree of filtration in order to protect the emitters from plugging. For most applications the amount of filtration is measured by the “mesh size” of the screen or maximum size in “microns” of an object that can pass through the filter.
During the ﬁltration process, the discs are tightly compressed together allowing clean water to pass through the discs and trap debris.
Filter installed either vertically or horizontally.
Use Teflon tape on filter end connections.
Make sure that the inlet and outlet orientation is correct (shown by arrows on filter).
Prior to start-up check for any transport damage to the unit (system operates under pressure!).
Cover clamps need to be properly closed.
- Turn off the water.
- Release the pressure through the drainage valve.
- Open the filter clamp and remove the cover.
- Unscrew and remove the filter element.
- Wash the filter element.
- If the filter discs require acid treatment you may dip the complete filter element in acid according to our recommendation.
Care should be taken to keep the operating pressure differential across the ﬁlter between 2-3 m. Pressure reading should be monitored sufficiently to detect any buildup of pressure differential during normal operation, which indicates the start of ﬁlter Disc plugging. When this occurs, the system should be shut down, the ﬁlter drained and disassembled. The disc element should be washed thoroughly using a high pressure spray washer, spraying from outside in.
If the filter disc are covered with lime deposits, then remove the element and treat with acid.
Maintenance Cleaning the Discs
When cleaning of the discs is required, please follow the steps described below:
Make sure that system is not under pressure!
Release the clamp and remove the cover.
Remove the discs
Wash the discs with fresh water and then reassemble the discs on the spines.
Check that the correct quantities of discs are assembled on the spine.
Reassemble the filter cover and tighten the clamp.
For operation and maintenance of the filter please follow the instructions in this manual.
Installation of the filter should be performed so as to avoid direct water splashing on any of the filter parts.
- Confirm that filter weight, when full, meets the support construction requirements.
- Prior to installation confirm that line pressure match’s filter operational pressure
- During installation, use standard flanges and connections only.
- Check that all filter flange bolts are properly secured.
- Before opening the filter clamp, check that there is no pressure in the filter.
Mais for Irrigation and Water Systems is designing Group filters adequate for your project (manual OR automatic).
For more information contact technical support in MAIS manufacturer.