יום רביעי, 30 בדצמבר 2009

drip irrigation systems

Drip Irrigation method, also called drop by drop, functions as its name imply. Drop by drop water is distributed to the active root zone of plants. This method, if managed properly, might be the most water-supply-efficient way of irrigation, because runoff and evaporation reduced significantly. Drip irrigation in today's agriculture, is frequently integrated with plastic sheet, further diminishing evaporation, and is also a method of fertilizers delivery to the plants. This process called fertigation (fertilizer + irrigation).
Drip Irrigation system layout and its components

Deep trickle (percolation), where water moves below the active root zone, can happen if a drip system is running for too long time or if the irrigation application rate is too high. Drip irrigation systems vary from high-end and computer controlled to simple low-tech with intensive labor involved. Relatively low pressures, is required for most types of micro irrigation systems. System can be planned with uniformity within the field or for exact water conduction to individual plants in a field containing a mix of plant types.Even though it is complex to regulate water pressure on steep slopes, PC emitters (pressure compensating) available, so drip systems can handle you can handle unleveled fields as well. Water pressure regulation and filtration to remove particles are primordial in any drip system. Drip systems tubes are usually black, however there are also brown, blue and even white tubes. Some drip tubes are buried under soil or mulch to prevent the growth of algae and to protect the PE (polyethylene) from degradation due to ultra-violet radiation. Sometimes a drip irrigation system can also be a porous clay vessel inserted into the soil and periodically filled from a hose or a watering can. Succesfull farmers around the globe use drip systems to irrigate almost any intensive crop or plant. find more information on drip irigation equipment.

יום חמישי, 30 ביולי 2009

Hydro-cyclone, Filtration for Irrigation systems 5

Hydro-cyclone [Centrifugal Filters]: Also known as "sand separators, centrifugal filters are mainly for the removal of particles such as sand, and other solids from the irrigation water. They are ideal for situations where a pile of sand, is present in water.How it works? Dirty water enters the filter where swirl around the inside of a cylinder. The centrifugal force causes the sand particles to move towards the outer edge of the bottle, which slide slowly down the side of a reservoir below. Hydro-cyclone centrifugal filters are reasonably cheap, very simple and very effective to remove the sand from the water. Since many wells pump water with sand, It is not uncommon for a small amount of sand to pass through a centrifugal filter. In the case of drip irrigation you should always add a Backup disc filter when using a centrifugal filter(sand separator) as a safety precaution. A sand separator filter (hydro-cyclone) is used in combination with a filter media after it has an excellent combination. The hydro-cyclone removes the sand filter media and removes the material organic. It should be noted that selection of hydro-cyclone sand separator filter must be closely combined the Flow rate [m3/h or gph] of the system or the filter will not work properly. Always check with the vendor working flow-rate/pressure head loss curve guidelines on the design of a hydro-cyclone filtration system for your irrigation system, remember, a minimum pressure head-loss is necessary to achieve effective sand separation.
Next Blog will be about "How to choose a filter?"


Jack Z
Irrigationglobal.com


Disc Filter, Filtration for irrigation systems 4


Disc Filters
Disc Filters integrate the benefits of the old irrigation water filtering methods screen and media, as well as having their own unique advantages. Disc Filters are useful for filtration of both sand granules and a variety of organic materials. Disc filters are the best choice for almost any micro irrigation systems. Small Nylon discs are grooved on both sides of each disc to a specific micron size. A series of these discs are then stacked and compressed on a specially designed spine. When stacked, the groove on top runs opposite to the groove below, creating a filtration element with a statistically significant series of intersecting grooves which trap the solids. The stack is enclosed in corrosion and pressure resistant housing. During filtration, the discs are tightly compressed together by a combination of either spring power or tightening nut and the differential pressure, thus providing high filtration efficiency. Filtration occurs while water is percolating from the outer diameter to the inner diameter of the element. Depending on the micron grading, in irrigation water filtration it is common to use from 18 (in 400 micron discs) to 32 (in 20 micron discs) disc quantity per each 1 cm of the spine length stopping points in each track, thus creating the unique in-depth filtration. During the filtration process, the filtration discs are tightly compressed together by the spring's power (or tightening nut) and the differential pressure, thus providing high filtration efficiency. Filtration occurs while water is percolating from the peripheral end to the core of the element.
The Disc Filter is cleaned by unscrewing the disc's tightening nut, and wash the released discs under strong flow of water. The discs roll around a central spine rapidly, thus part of the dirt is separated due to the centrifugal force. Disc filters are todays default filtration method for any drip irrigation system.
For automatically cleaning the discs, there is a releasing mechanism of the clamp between the discs, thus separated from each other the trapped particles are released and back-washed, know methods called Spin klin and Spin clean.


Filter media, Filtration for irrigation systems 3


Filtering irrigation water with media (sand/gravel) filters, also known as depth filtration for irrigation systems. The media filters perform the filtration of water through a thick layer of graded particles. These particles can be sand, gravel or other granular sorted materials. The filtration grade depends on the effective size of the bedding and the water velocity passing through the filter.

How the Sand / Media filters work:
Water enters through the filter inlet and percolates through the filter bed. When suspended matter comes in contact with media particles, it absorbs it. Clean water then goes via the strainer collectors, located on the bottom of the filter tank through the filter outlet. Cleaning is done by backwashing. Water is inserted in reverse direction - from the strainer collectors upwards, causing suspension of the filter bed, thus releasing the suspended materials from the bedding and it is flushed out through a backwash valve. Backwashing may be done automatically according To pressure differential and/or according To time intervals. When your water source is a river, open reservoir or wastewater, media filters might be the heart your drip irrigation system.


Jack Z.
Irrigationglobal.com

Screen filters, Filtration methods common in irrigation systems, 2


Screen Filters are probably the oldest and most common in irrigation systems. They are excellent in their ability to remove hard particles like rust. But when it comes to sand, it can get stuck inside the screen and rapidly block it. Usually Screen Filters are less expensive. Delicate organic materials cross the screens and raw material usually smears on top of the screens, deriving a more frequent cleaning interval. The common solution in Screen Filters is enlarging the filtration to expand the cleaning intervals. Today, there are several modern solutions of self-cleaning Screen Filters. This is done by back-washing and / or repeat wash using a sprinkler with inner spraying nozzles for cleaning (similar methods used in commercial dish-washers machines). In order to wash the filter in clean water, it takes at least 2 parallel filters, so that one contributes clean water to wash the other. Semi automatic screen filters are available as well, when the filter is being washed by turning a manual crank that rotate internal nozzles spine or a circular brush. If there is no automatic self-cleaning mechanism, the use of Screen Filters is not recommended in case the water contains organic materials. Clogging of material on top of the screens causes a large pressure difference that can bring to the collapse of the screen, or decreasing and even full stopping of irrigation water flow. The Screen Filter is cleaned by removing the screen and washing it under Strong flow of water or by using a suitable brush. The common irrigation screen filtration elements in the market are usually made of Stainless Steel, Polypropylene or Nylon. for drip irrigation use a 120 mesh to 140 mesh screens.
Jack Z.

Water filtration is very important to almost any irrigation system, 1


Appropriate filtration can help to extend the life and improve the maintenance of any irrigation system. For drip or micro sprinklers emitters, filtration is a basic need to avoid clogging.
A sand grain, rust and other materials can block micro and mini and sprinklers’ nozzles which could cause unintentional plants dehydration. Many water sources like reservoirs, rivers and of course waste water contain a lot of organic materials such as alga and bacteria, that have to be removed especially from drip irrigation, mist spray [Nebulization] and micro-sprinkle systems, as small as they are. Not removing those substances can lead to creation of dirt accumulations and colonies of harmful material within the emitters and the rest of the equipment. Naturally, rust and sand grains are a safe platform for coating by organic materials and creating large chunks within the irrigation systems, causing a total blockage of water transferring.
Jack Z.

יום חמישי, 23 ביולי 2009

Ho to write Irrigation in 31 languages

Ho to write Irrigation in 31 languages
drėkinimo
nawadnianie
灌溉
напояванеالري
zavlažování
kunstvanding
irrigatie
patubig
kastelu
Bewässerung
άρδευση
सिंचाई
öntözés
השקיה
irigasi
irrigazione
かんがい
관개
apūdeņošana
آبیاری
nawadnianie
irrigação
irigare
орошения
орошение
riego
bevattning
ชลประทาน
sulama
thuỷ lợi


Jack Z.

יום שני, 20 ביולי 2009

Who needs filtration for irrigation, 0

Water filters

Why a filter is needed?
Water filtration is very important to almost any modern irrigation systems.
Adequate filtration can help to extend the life and improve the maintenance of any irrigation system.
For drip irrigation
systems filtraters are a basic need to avoid clogging.
See more in my next blogs regarding filtration for irrigation
Jack Z