Filtronics, Inc

Filtronics, Inc. - A Tradition Of Reliability

In 1974, a group of forward-thinking entrepreneurs and engineers purchased a small Southern California company that manufactured water filtration systems.

However, the new owners discovered that many of the existing systems required re-engineering and upgrading if the company was to remain price and performance competitive. The result was the development of new systems that offered economical and operational efficiencies.

Across the country, Filtronics systems are providing continuous and economical service, maintaining Filtronics' long tradition of reliability in the field of water filtration.

From municipal surface water and groundwater to industrial waste water, Filtronics systems filter contaminants and solids effectively and simply...day after day.

Pressure Filtration

Filtronics, Inc. is a manufacturer of down flow pressure sand filters, to use general terms. It does not, however, employ sand or any silica products in its product line. When Filtronics was founded in 1974, its approach to filtration technology was vastly different from the rest of the industry. Media filtration technology had been based on the 25 micron straining capabilities of the conventional media design, utilizing 0.45 mm to 0.55 mm silica sand and a nominal 1.0 mm anthracite. By and large the industry has been content to limit its developments to the refinement of this media in terms of the gradation and the durability of the product. Filtronics has expanded these refinements by broadening the selection of media and by developing media with certain adsorptive qualities. Filtronics does not use any media consisting of silica sand.

Filtronics' approach to filtration is to design a media which has qualities that are particularly suited to the application rather than to supply one media to a variety of applications. For example, a media particularly well suited to the removal of iron and manganese from well waters is not as well suited to the task of removing very fine particulate matter such as giardia and cryptosporidium from a relatively clean water. Filtronics currently produces a series of nine proprietary media suitable for a variety of water and wastewater applications. The development of Electromedia® has resulted in some significant beneficial operating characteristics.

Electromedia® - The Heart Of The Filtronics System

The efficiency and effectiveness of any water filtering system depend on the filtering media. Filtronics' exclusive Electromedia® permanent filtering media is the most effective and economic filtering media available today.

Electromedia® is a granulated, naturally occurring sand-like filtering media that can filter particles as small as 2 microns. It is not a resin, plastic, or silica product, but instead a specially processed mineral that can filter up to 10 gpm per sq. ft.–with the same or better performance than other systems that filter only at 3-5 gpm per sq. ft.

By combining the remarkable filtering capabilities of Electromedia® with Filtronics' highly advanced system design, performance is optimized for every phase of operation including standard backflush, which takes only 4 minutes and thus reduces the quantity of waste materials to be handled. Competitive systems require 15 minutes or more.

The bottom line is a water filtration system that requires less space to operate, offers far better filtering effectiveness, and provides greater overall economics in virtually every application.

Electromedia® is the key to Filtronics system capabilities. State-of-the-art design is how Filtronics makes the key work–for you.

Backwash Duration

All Electromedia® work with a four-minute backwash duration. Backwash rates are 15 gallons to 20 gallons a minute per square foot, depending upon the media selected. The short duration results in lower wash water requirements and thus provides a better backwash-to-filtration ratio. The high rate and media design provide complete fluidization of the working media. Thorough cleaning of the media is obtained without the requirement of filter cleaning aids such as surface wash and air scour. This feature results in a significant reduction in initial capital investment and reduced operation and maintenance costs by eliminating the air scour equipment, associated plumbing and controls. This is true even in treating traditionally difficult supplies or removing heavy metals from the wastewater discharges of the metal finishing, electronics manufacturing and metal plating industries.

High Filtration Rates

The second significant feature of these media is their capability to operate successfully at filtration rates of five, ten and fifteen gallons per minute per square foot. Conventional systems must operate at one-third to one-fifth the rate to achieve comparable results. The benefit: substantial savings in the initial capital investment for smaller and more compact equipment. Significant savings may be realized by the construction and use of smaller facilities. The smaller filter size also translates into lower wash water requirements and further enhances the backwash-to-filtration ratio for a more efficient system.

A very brief discussion of five of the Electromedia® filtering systems follows. Supporting test data and technical descriptions are found in the sections labeled Electromedia® I through Electromedia® IX.

Electromedia® I - For Arsenic, Iron and Manganese

Electromedia® I is a unique system for the removal of iron and manganese from groundwater supplies employing a special chemical pretreatment system that utilizes chlorine as an oxidant, sulfur dioxide as the catalyst and two separate chemical reaction vessels to achieve the full oxidation of iron, manganese, any sulfide compounds present and other trace metals. This is followed by filtration with the adsorptive media capable of operating at rates of five to fifteen gallons per minute per square foot depending on the general mineral and total organic carbon (TOC) analysis of the water to be treated. If the water being treated has highly corrosive tendencies, a pH correction may be employed across the second reaction vessel. Other treatment alternatives would be considered as indicated by the chemical analysis. In the case of high TOC raw water, other oxidants or post filter treatment methods may also be employed. Hydrogen peroxide or ozone may be selected to minimize the development of trihalomethanes (THMs).

Since the application of the first Electromedia® I system in 1973, on a flow of 1500 gallons per minute at a rate of 20 gallons per minute per square foot, many systems have been installed that provide reliable consistent service. It is interesting to note, however, that to date almost every system furnished is operating at a rate of ten gallons per minute per square foot or greater.

Since the application of the first Electromedia® I system in 1973, on a flow of 1500 gallons per minute at a rate of 20 gallons per minute per square foot, many systems have been installed that provide reliable consistent service. It is interesting to note, however, that to date almost every system furnished is operating at a rate of ten gallons per minute per square foot or greater.

The system is particularly noteworthy because of its simplicity and economy of operation. Special controls and simple analytical equipment provide the simplicity. The economic advantages are derived from the reduced costs of chlorine versus the high costs and difficulties of application of the traditional oxidant, potassium permanganate, in the conventional manganese greensand/potassium permanganate system. Eliminating the potassium permanganate eliminates all possibility of pink water complaints.

Electromedia® II - Turbidity Filtration

Electromedia® II is applied to relatively clean waters where a very high quality water is required, for either process or drinking water needs. Typical applications include process water in the food industry, prefiltration, softening, deionization and reverse osmosis.

Electromedia® II media will filter waters having a turbidity of generally less than ten units to produce water qualities of less than one unit. It is capable of filtration in the two micron range and is very suitable for water low in colloidal materials. It has experienced operation in higher turbidity ranges with satisfactory results.

Electromedia® II operates at a filtration rate of 15 gallons per minute per square foot. It will achieve filtrate qualities of less than one unit without the use of alum or any other coagulant. Followed by disinfection, it can provide a water suitable for serving the public with turbidities less than 0.5 NTU.

Electromedia® II has found wide application in filtering city water supplies preceding reverse osmosis equipment. It has been employed regularly by several leading reverse osmosis equipment manufacturers. Electromedia® II is also used to enhance the operation of deionization and softening units where process water supplies have turbidities greater than one unit.

Electromedia® IV – Wastewater Streams

Electromedia® IV is applied to treated and clarified sanitary wastewater. It operates without the use of alum or polymer. The Electromedia® IV unit employs a surface wash cycle to combat the effects of clarifier upsets and the accumulation of heavy solids in the upper layers of the media. The special control system provides for a daily backwash on a time basis as well as providing for backwash on a differential pressure override basis. Utilizing the chlorine contact chamber as the source of the backwash supply and chlorinating again at the discharge of the backwash supply pumps prevents the media from going septic.

These systems are applied at rates of up to ten gallons per minute per square foot. Reports that demonstrate Electromedia® IV performance capabilities are found in the Electromedia® IV section. There are many successful applications of Electromedia® IV that are more than ten years old. Although many were purchased to enhance the operation of package sewage plants that were overloaded hydraulically or inadequately designed, as many were supplied to original equipment manufacturers for use in their initial designs. The units have been supplied for conventional plants in the one and two million gallon per day range.

Basically, if the Electromedia® IV filtration system receives a properly treated secondary effluent containing 50 milligrams per liter of suspended solids, it will produce a filtrate of five milligrams per liter or less.

Electromedia® V – Surface Water Treatment

Electromedia® V is designed to meet the surface water treatment rule standards for potable water. It is employed when the source water is from lakes, canals, streams or springs and contains a high proportion of colloidal material and turbidities up to 30 units to give maximum protection and removal of giardia and cryptosporidium.

Electromedia® V will utilize an alum feed to coagulate the colloidal material. Alum injection occurs ahead of a reaction vessel. The reaction vessel is sized to obtain a flocculation time of 20 minutes or less depending on temperature and to provide good mixing. In small systems, this may be accomplished in a run of pipe. In larger systems, a vessel is employed. Typically turbidities of less than 0.1 are achieved. A rinse to waste step is standard. Recovery to a turbidity of less than 0.5 is achieved in less than five minutes during the rinse to waste step.

Unlike conventional filters, Electromedia® V mechanically strains in the 2 micron range without alum at 10 gpm per square foot. Pilot test and actual results in the Electromedia® V section demonstrate the capability of Electromedia® V to produce a high quality filtrate. Note particularly the data demonstrating particle counts in the 15 to 50 range with peaks of only 300 at the end of the filter run. No clarifier is employed in the treatment train.

Electromedia® VI - Heavy Metal Removal

Electromedia® VI is applied to a heavy metal wastewater stream following chemical treatment and clarification. If the chemical treatment equipment is not existing, Filtronics will utilize its rapid mix, flocculation and parallel plate clarification equipment followed by an Electromedia® VI filtration unit. The pretreatment equipment is modular in nature and may be selected by component for the optimum performance. Generally, designs are based around 20 seconds of rapid mix, 20 minutes of flocculation and a clarifier overflow rate of 600 gallons per day.

The parallel plate clarifier with its unique SuperSlant® proprietary 60° corrugated design allows for a compact installation as well as the gravity withdrawal of accumulated solids. The design utilizes the sludge blanket for solids contact clarification. The sludge, reaching a concentration of up to 2%, may be handled by a conventional filter press. The resulting filter press cake would contain solids up to 30% in concentration.

The treatment chemistry, of course, would be dependent upon the type of application. Chrome and cyanide wastes would be treated separately prior to meeting the treatment train. Chrome is reduced at a low pH to chrome +3 and then passed to the treatment train for a pH adjustment to 8.5 for precipitation as a hydroxide. Cyanide must be maintained at pH of 8.5 or greater and oxidized to cyanate or carbon dioxide and nitrogen, as required by regulation. The pregnant liquor would then be passed on to the treatment train where any of the remaining metals would be precipitated. Special chemical or a combination of chemicals is employed when chelated metals are present. The use of sulfides is avoided whenever possible to remove the inherent problems of safety, corrosion and special sludge discharge requirements.

Other Electromedia® Systems

The Electromedia® VI filtration system employs a special cleaning system that effectively removes those particularly difficult adhesive precipitates such as chrome, zinc and lead. This cleaning mechanism is utilized on a preventive maintenance basis approximately once a month.

Electromedia® VI saved TRW Corporation substantial penalties when its conventional system was unable to meet the chrome discharge limits in 1976.

Other Filtronics units are employed for sea water filtration or brine injection in the petroleum industry. Cooling tower side stream filtration and exotic problems like arsenic and fluoride are also treated. See the special report, 'Arsenic Removal from Groundwater,' in the Electromedia® IX section.

Whatever the treatment requirements, Filtronics marries expertise in chemical pretreatment to the application of conventional technology with its exclusive Electromedia® filtration systems to provide reliable, cost effective treatment processes.

• Pilot Study
  Filtronics “full scale” pilot units provide long term, real time field tests to collect data and document the treatability of the water source. In addition, the pilot test will verify the chemical oxidation demand, determine the chemical feed rates, electrical operating costs, and document the removal efficiencies.
• Media Core Sampling
  A core sample is a physical measurement of the depth of each layer of media in your system to determine media depletion, if any, resulting from ordinary backwash cycles, water chemistry, and/or water quality.
• Media Replacement Service
  Filtronics offers a turnkey solution to replace exhausted media in your existing water filtration system. When it’s time, why not have peace of mind and let our team of highly trained professionals take care of the entire process.
• Onsite Services
  Our job isn’t over once your equipment is installed. The award-winning service team at Filtronics has the training to provide expert support for all of our products. To get maximum performance from our equipment throughout its life, Filtronics recommends that our clients follow the indicated preventive maintenance schedules for their systems.