Flow Rx

self cleaning water filters are the optimal choice for most industrial/commercial, municipal and irrigation applications. self cleaning water filters are reliable, require low maintenance, have a short cleaning cycle, waste very little flush water, are easy to install in new or existing water filtration systems, and do not interrupt main flow during the backwash cycle. A Self cleaning filter may also be referred to as a; self cleaning screen filter, self flushing water filter, self cleaning strainer, automatic water filter, or sediment filter.

HOW IT WORKS

90 Series Self Cleaning Water Filters

 

180 Series Self Cleaning Water Filters

 

LP180 Self Cleaning Water Filters

 

A self cleaning filter is a type of water filter which utilizes system pressure to clean itself. A rigid cylinder screen strains particles from a water source, trapping debris on the inside. This layer of buildup causes differential pressure across the inlet and outlet. A controller monitors the filter and opens a flush valve when it senses adequate differential pressure. This creates rapid flow through the internal cleaning apparatus, which vacuums buildup from the screen and expels it.

Forsta 180 Series Backwash Cycle

A unique characteristic of self cleaning filters is that the backwash cycle does not require the entire system flow to stop and reverse, as is the case for many other types of filters. Instead, a point-of-suction backwash reverses flow across the screen only directly in front of suction nozzles. This allows the cleaning mechanism to scan and clean the screen incrementally without disrupting the main flow through the filter.

Self cleaning screen filters are used in a variety of applications where continuous water flow is crucial, including equipment protection in industrial water filtration, nozzle protection in irrigation filtration systems, and membrane protection municipal water filtration systems.

FILTER SELECTION:

Deciding between a self cleaning water filter and other technology

When making a water filter selection it is important to assess the variables:
  • Reliability required by the system
  • Installation costs
  • Operating and maintenance costs
  • Wastewater replacement
  • Pressure
  • Flow Rate
  • Necessary degree of filtration

It is important to select the correct type and size of water filter. A properly designed system will be able to handle unforeseen overload and adverse conditions.

Plan for a greater water flow than the system is expected to require. It is always better to have more capacity than not enough. A properly sized filter will save time and money in the long run.

It is recommended to choose a screen element that is appropriate for the application. For example, if a water filter is needed to protect spray nozzles, a filtration degree of 100-200 micron is sufficient. Using finer filtration than that would require increasing the screen area.

Waste disposal costs are frequently overlooked when implementing quick solutions. Installation cost must be weighed against operating cost. Sand or media filters can take up to 10 minutes per backwash and upwards of 1000gal during one cleaning cycle. Forsta self cleaning water filters require minimal flow (as little as 20 gallons) per cleaning cycle, even in models that flow up to 7,350gpm.

Filter Type Efficiency Cost Installation/
Operation
Size Degree of
Filtration
Maintenance
FORSTA Self Cleaning Water Filter High
Flush water volume is very low and flush time is fast – 4 to 16 seconds
Med-High Easy Automatic operation does not interrupt system flow during the rinse cycle Small 5 micron Low
Gravity Coanda Effect Screen Low Cannot be used in pressurized systems Low Easy Large 200 micron and up Requires periodic cleaning
Bag and Cartridge High Med-High Easy Small Sub micron Labor intensive. Requires bag or cartridge change outs
Media (Sand) High
However, flush water volume is large and flush time can be very high- as much as 10 minutes or more
Med-High Twin systems are required for uninterrupted automatic operation Large 1 micron Requires periodic media changes
Centrifugal High
Batch or continuous low flush water
Low Suitable for full-time automatic operation: Small-Med Captures down to 75-micron level but cannot filter particulates below ~ 1.1 specific gravity. Cannot filter algae and is flow sensitive
Tangential Screen Low
Require high flow cleaning cycle
Low Can be adapted to automatic operation Small Labor intensive. Requires periodic screen removal and pressure wash cleaning.

LOW MAINTENANCE

The self cleaning mechanism in a Forsta self cleaning water filter eliminates the need for routine maintenance by automating the cleaning cycle. Differential pressure is monitored by the controller which initiates the backwash cycle automatically. As a result, Forsta self cleaning technology saves maintenance time and operating cost. Manual washes, spray downs, filter, cartridge and bag replacements become unnecessary. Basic bi-annual or annual inspection (depending on particle load) replaces the need for daily, weekly or monthly shutdowns.

RELIABILITY

Well-tested and time proven design make Forsta industrial water filters a dependable choice. A wide range of clientele whose applications require rigid filtration parameters and uninterrupted function report great success operating self cleaning water filter technology. High standard material grade of Forsta industrial water filters prevents corrosion and guarantees a long life for each filter.

CONTINUOUS OPERATION

Debris collects inside the filter’s stainless steel screen. When differential pressure initiates the automatic cleaning cycle, flow reversal occurs at the point of suction rather than throughout the entire filter. This provides an important advantage in that it allows for continuous flow throughout the filter for the duration of each backwash cycle.

To preserve system continuity during bi-annual or annual maintenance, multiple self cleaning water filters may be installed in parallel. This configuration provides a larger cumulative screen area and allows one or more water filters to be removed from service for periodic maintenance without interrupting the filtration process.

SHORT CLEANING CYCLE

Forsta self-cleaning water filters require only 4-20 seconds to perform a backwash cycle. Other filter technologies, such as sand, or bag and cartridge filters may necessitate several hours to complete their cleaning process.

SUSTAINABILITY

MATERIAL - Forsta industrial water filters are at the forefront of sustainability. Forsta specializes in the construction of stainless steel industrial water filtration systems and irrigation filters. As people become more aware of their impact on the natural environment, the use of stainless steel as a production material, is gaining greater value than previously recognized.

In mill production 70-85% of the unprocessed material comes from recycled sources. Recycled stainless steel or other alloy scrap comprises the fundamental components that will create raw material after melting in an electric furnace.

Given that stainless steel is 100% recyclable, after exceptionally long life-spans, stainless steel products can be returned to a mill and forged into new raw material. Likewise, all stainless steel scrap left on hand in the production of new stainless steel forms is collected for recycling from within the plant itself.

The longevity of stainless steel products contributes to resource minimization since new resources are not required as frequently to replace corroded or worn products. Stainless steel that is recycled in electric furnaces is of equal quality as the original.

WATER - Efforts to use water more sustainably have led to a focus on conservation and efficiency. Infrastructure upgrades are continually improving water efficiency across the industrial, municipal and agricultural sectors. These advancements include the optimization of cooling towers and cooling tower filtration, recycling of sample water at cooling towers and implementation of closed loop water systems involving water reclamation and reuse systems. Forsta industrial water filters play an integral role in the performance of closed-loop systems by protecting equipment and ensuring uninterrupted flow.

Waste water treatment plants and pumping stations can connect (often through thousands of feet of reclaimed water pipes) to storage tanks, chillers, steam boilers and irrigation sites. Reclamation and reuse systems make highly treated or “reclaimed” wastewater available to meet a variety of non-drinking water needs thereby reducing strain on drinking water reservoirs and water treatment plants. Forsta self cleaning water filters using the point of suction backwash technology provide the industry’s most efficient water filter.

POWER - Protecting pipes from scale buildup with Forsta industrial water filters prevents an increase in the energy required to pump system water. As pipe orifices become smaller, more energy is required to pump the same volume of water. Effects of flowing dirty water include excessive scale buildup, contaminants settlement, and clogged spray nozzles which all contribute to poor pump performance. Implementing Forsta self cleaning water filters prevents these consequences and saves energy.

EASY INSTALLATION

Forsta offers self-cleaning filters in a wide range of sizes, orientations, and to varying degrees of filtration in order to answer any demand. Custom design solutions for unique applications are available as well. Forsta provides its self-cleaning water filters ready to install.

All Forsta self-cleaning water filters accommodate simple installation. The 180 series of filters have a parallel flange configuration, and will integrate with any straight pipeline.

The 90 series filters exhibit a right angle flange configuration that provides a compact filter unit.

Zero Series and Coarse Strainer automatic water filters have a straight flange configuration and like the 180 series, will also integrate with any straight pipeline.

Skid Mounted units are ready-to-go custom industrial water filters mounted on a single platform. Skid Mounted filtration systems combine any self cleaning filter model with required pumps, manifolds, and controllers.

SYSTEM CONTROL

The control system of a self cleaning water filter is an important part of the package. It is designed to be reliable, easy to operate and capable of initiating a flush cycle either by high differential pressure or on a timed basis. Forsta’s control systems provide an alarm function to warn operators of filter malfunction. LCD displays also indicate the number of times the Forsta self cleaning filter has backwashed.

Controllers are sized to fit the application ranging from large industrial controllers to small battery powered controllers. An industrial controller is capable of flushing up to four self cleaning water filters in parallel. The small, battery powered controller features a one-year battery life and is ideal for controlling filters located where a power source is not available.


SOURCE TESTING

Forsta offers a free water testing service for customers looking to determine the most cost-effective water filtration system. Send a one gallon water sample and Forsta will determine the right solution for your application. With a representative water sample our engineers can estimate how often a self cleaning filter will backwash and how much screen area will be needed to achieved the desired filtration degree.