* 5µ sediment filter and housing * Thin film spiral wound elements * Stainless steel pressure vessels * Low pressure visual alarm * Automatic

* Thin Film Composite membranes (TFC) * FRP membrane housing * Nickle-Aluminium-Bronze high pressure pumps * Permeate and

concentrate flow-meters * Low and high pressure safeguards * Compact frame with powder coated finish * Automatic operation with level

controls * Stainless steel back pressure control * 5µ sediment filter and housing * High pressure relief valve * Auto feed shut off * Liquid

filled system pressure gauge

* ROC-75 microprocessor / controller with: - Illuminated switches, auto operation, power / reset, manual - Pre-treatment lock out - Indicator

lights: tank full (with RO shut down) high pressure, pump on, low pressure, back wash

OPTIONAL EQUIPMENT

* TDS meter * Anti scalant injection * Sodium bisulfite injection * SS high pressure pump * Pulsation dampener * Crating * Pressure relief

valve * Hour meter * Filter in / out pressure gauges * Multimedia filter * Ultraviolet sterilizer (316 SS)

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* Adjustable thermostat for accurate temperature control * Electric and mechanical system prevents overflow of water from reservoir

* Noiseless circuit in compressor and booster pump * Function indicating LED lamps: - indicate operation of filtration system - indicate of

water level in storage tank - indicate of hot / cold water temperature * Overheating protection with bimetal sensor * Top and front panels are

ABS plastic * All function is controlled automatically * UV lamp is optional * Other purification systems are available up on your request

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GASKETS

Low profile inline strainers are used in applications where there is a minimum amount of space and which allow for a small filter area. If more

filter area is necessary, the low profile tops can be matched with a longer bowl, these assemblies are referred to as the mini Series. Common

applications for these strainers include, home water treatment systems, floor cleaning equipment and medical supply. The chart below shows

common dimensions for standard assemblies, however, tops are also available with female whit-worth threads in polypropylene and nylon.

Agricultural and power spraying equipment are two of the markets for which these strainers are used. The midi size bowl is not available in

6/6 nylon. The assembly uses a buna O-ring in place of the gasket.

INTERMEDIATE SIZE

These assemblies are the most commonly used due to their compact size but large filter area. A few of the many markets they are used for

include, dental supply, commercial and industrial pumps, agricultural and marine. Although the standard port is NPT, this Series can be pur-

chased with hose barb, BSPP and whit-worth ports.

LARGE SIZE

The large size strainers are used primarily in the same applications as the intermediate size. The advantage of these assemblies, however, is they

have an increased flow rate and filtration area.

TECHNICAL INFORMATION

Cleaning Requirements: All wire mesh elements can be easily cleaned or replaced, without removing the entire strainer from the line, by remo-

ving the bowl. Basin bowls are cleaned by flushing through the bottom port.

Filter Shipments: Inline strainers can be shipped either as complete assemblies or as individual components. Strainers are shipped bulk unless

otherwise quoted.

Flow Rate: The above chart outlines the approximate pressure loss at increased gpm.

Pressure Ratings: All of Ronak inline strainer assemblies have been proven to perform at pressures up to 150psi at 70°F and 100psi at 125°F.

Pressure Spikes: Ronak inline strainers are not intended for applications where pressure spikes in excess of maximum pressure ratings can be

expected.

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THE DIFFERENCE BETWEEN RO, NF, UF AND MF

The four classifications of membranes look similar, but are physically and functionally unique. Their creation requires highly advanced polymer

chemistry manufacturing techniques involving the coating of thin layers of various types of very porous polymers, or plastics, onto backing

materials. Depending on the material, process and chemistry involved, either a reverse osmosis, nano-filtration, ultra-filtration, or micro-

filtration membrane will emerge. The principle difference between each type of membrane is in the size of the pores reverse osmosis membrane

pores being the smallest, measuring between 1-15angstrom. To visualize the scale, try imagining the entire Pacific Ocean as one square foot

of membrane. In this scenario, the size of a reverse osmosis pore would be roughly the size of a dime, a nano-filtration pore would be the size

of a bottle cap, and an ultra-filtration pore the size of a compact disc. Membrane pores are small indeed! While each of the four membrane types

is very similar physically, they each perform very different functions in varying application environments. In general, RO and NF membranes

are capable of separating substances as small as ions from feed streams, while UF and MF membranes typically separate larger molecules.

All four-membrane types allow water, but not all solvents, to pass. Typically, RO membranes reject at the ionic level, and NF membranes are

usually used to reject high percentages of multivalent ions and divalent captions while allowing mono valent ions to pass, thus displaying a

unique ability to separate differing ions from one another on the basis of their chemistry. UF and MF membranes reject molecules on the basis

of size, UF retaining particles larger than about 15-200 angstrom and MF membranes retaining particles larger than about 200-1000 angstrom.

UF and MF membranes are typically rated in terms of pore size and porosity, while RO and NF membranes are rated in terms of percent rejec-

tion of a specific salt, and in terms of flow.

THE DIFFERENCE BETWEEN MEMBRANE SEPARATION AND CONVENTIONAL FILTRATION

There are distinct differences between membrane separation technology and conventional filtration. RO, nano-filtration, ultra-filtration and

micro-filtration separation technologies all combine  pressure with unique membranes to remove impurities from water. The technology

employs the concept of cross flow filtration whereby the fluid being filtered, the feed steam, is split into two streams:

1.) A permeate stream consisting of the filtered, pure water

2.) The concentrate stream containing the rejected impurities.

In splitting this feed stream in two, flow is directed both through the membrane (creating the clean permeate stream), and across or parallel to

the membrane, creating the impure concentrate stream, or reject. This cross flow filtration system is unlike conventional dead end filters, which

flow in one direction, through the filter. The major advantage of cross flow filtration is that the impurities that are captured on the membrane is

constantly swept away by the concentrate stream, thus continually cleaning the membrane surface. This prolongs its life and reduces mainte-

nance costs. In contrast, conventional filters accumulate the captured impurities on the filter medium and must be periodically cleansed and / or

replaced, posing obvious economic and/or environmental disadvantages. Membrane technology works by exploiting and overcoming a natural

law of physics and chemistry. In short, the speed of water transport through semi-permeable membranes is governed by pressure, while the

speed of salt transport through semi permeable membranes is governed by the salt concentration gradient. Typically, water transport is faster

than salt transport, a convenient phenomenon exploited by engineers in the development of membrane technology's separation capabilities. In

natural systems, these governing influences result in clean (or dilute) solutions having a natural tendency to flow across a semi permeable

membrane towards saltier (or more concentrated) solutions. This tendency is called osmosis, the strength of which is governed by how

concentrated or dilutes the two solutions are. The resulting flow is regulated by the amount of energy that is accumulated in the concentrated

solution as it attracts more and more of the dilute solution. At the point where the concentrated solution acquires enough energy to stop the

inflow of dilute solution, equilibrium has been achieved. This phenomenon is common in nature and is the mechanism by which a plant root

and the human blood stream absorbs water and nutrients. In order to reverse the natural tendencies of water and salt movement and force clean

water to flow from salty water, the osmotic pressure must be overcome, i.e. osmosis must be reversed. In order to reverse this flow of water,

membrane systems, and RO systems in particular, utilize a specially constructed semi-permeable membrane element enclosed inside a pressure

vessel. Pressure is applied to reverse the flow of water, the source of which is usually an existing, pressurized line for smaller volumes, or the

addition of a pump for larger installations. As pressure is applied to the feed stream, water molecules are passed through the membrane while

salts are retained in the feed. Thus, utilizing the principles of water and salt movement, and combining them with pressure and membrane

technology, the natural osmotic flow of solutions is reversed.

HOW RO MEMBRANE TECHNOLOGY IS USED TO PURIFY WATER?

In small residential or light commercial applications, RO membranes are typically used to purify varying qualities of saline water. In a common

application, the appropriate RO membrane element is housed inside a pressure vessel that accepts inflowing, pressurized saline feed water.

Cross flow filtration across the membrane then divides the flow into two outflow streams: the cleansed permeate feed, and the concentrate or

reject stream. The rate at which permeate and concentrate streams are created is controlled by a flow control valve. This valve must be set to

allow sufficient feed stream to flow in order to cleanse the membrane surface, otherwise membrane fouling may occur. More than one element

may be employed at a time depending on the permeate quality requirement and quantity of the feed stream. In some cases, up to a total of seven

elements may be loaded inside a single housing, the interconnected central tubes collecting the clean, permeate stream. The concentrate stream

becomes increasingly more saline after each successive element, and is finally discharged from the last element.

RO MEMBRANE PERFORMANCE

RO membrane performance is typically described in four different ways.

1.) Recovery indicates the ratio of permeate flow to feed flow as a percentage. It describes the volume of clean water produced, the higher the

percentage the better.

2.) Salt passage indicates the ratio of permeate salt concentration to feed salt concentration as a percentage. It describes the volume of salt in

the permeate, the lower the percentage the better.

3.) Salt rejection indicates the difference between 100 and the salt passage and is expressed as a percentage. It describes the amount of salt

separated from the clean water, the higher the percentage the better.

4.) Permeate flux describes the rate of clean water production per unit area and is usually expressed in gpd per square foot, the higher the

number the better.

In most cases, membrane performance is described by the last two terms, salt rejection and permeate flux. Many factors influence the dual goal

of removing undesirable species from a given water supply while at the same time delivering a reasonable flow of purified, permeate water.

These factors include operational, storage and handling, maintenance and pretreatment design parameters, all of which may drastically affect

membrane performance. Operational, storage and handling parameters are discussed in the following sections.

OPERATIONAL PARAMETERS

Operational performance parameters include pressure, temperature, and recovery, feed water salt concentration and pH. A description of them

is as follows:

Pressure: As the pressure exerted on the feed solution increases, both the permeate flux and percentage rejection increase. Water flow across

a membrane is directly influenced by pressure, whereas salt flow across a membrane is independent of pressure and is only influenced by

concentration gradients, moving from concentrated solutions to dilute solutions. As a result, increased pressure removes more and more water

from the concentrate stream, which in turn increases flux.

Temperature: As the temperature of the concentrate solution increases, flux increases and percent rejection decreases. Temperature affects

the coefficients of permeate and salt passage about the same. As temperature increases, water permeability across the membrane improves and

flux increases. Percent rejection remains about the same at lower temperatures, or decreases slightly at higher temperatures.

Recover: As recovery increases, both the flux and percent rejection decrease. Increased recovery increases the osmotic pressure of the feed,

which in turn reduces the net driving pressure and flux. Percent rejection is also reduced since the concentration gradient across the membrane

has been increased.

pH: As pH changes from acid to base, the rejection characteristics of some substances will change. Many substances exist in equilibrium with

analogs of themselves, a relationship that is pH dependent. As pH drives the equilibrium in one direction or another, the rejection characteristics

of the particular molecule may also change.

TEMPERATURE CORRECTION FACTORS

Temperature correction factors are listed all reverse osmosis, nano-filtration, ultra-filtration and micro-filtration elements. The reference

temperature is 77ºF (25ºC).

STORAGE AND HANDLING PARAMETERS

Membranes are developed under extremely precise conditions, and must be stored and handled properly to insure maximum performance and

shelf life. In order to simplify storage and handling for our customers, Desalt membrane products are shipped dry. Dry shipment helps avoid

bacterial growth, and prolongs shelf life without jeopardizing optimum product performance.

If elements are stored in the original box with the polyethylene bag intact, Osmonics warrants all dry shipped elements to perform at:

1.) Ambient temperature under 100°F (38°C) for six months.

2.) Temperatures between 100°F (38°C) and 122°F (50°C) for three months.

SPIRAL WOUND TECHNOLOGY PREFERRED CONFIGURATION

Cross flow membrane modules are available in various configurations. Tubular, hollow fiber, flat sheet and spiral wound membranes are all

available in the marketplace, each possessing relative advantages and disadvantages. Spiral wounds are chosen for their efficiency and economy.

Spiral wound membranes were developed by Osmonics to overcome key engineering challenges. First, spiral wound membrane elements are

compact in size, capable of high flows and resistant to extremely high pressures. The spiral design achieves these goals in a rugged, leak free

and pressure resistant configuration. In addition, advanced element construction options allow for unprecedented design flexibility for a variety

of applications. Today's choices of materials and options in spiral wound technology allow for preferential separation, minimal fouling and high

performance under extreme chemical, pressure and temperature environments. Other element configurations were unable to meet these

important engineering objectives. Element construction involves precise assembly of key component parts. An element basically consists of

sheets of membranes, permeate carriers, feed spacers, a permeate tube, an anti telescoping device, an interconnector, an end adapter, an outer

wrap and glue. To build an element, a sheet of porous material called a permeate carrier is first placed in between a sheet of membrane that has

been folded in half, creating an envelop, or "leaf". The permeate carrier both supports the membrane against the high operating pressures exerted,

and provides a flow conduit for the clean, permeate water which has passed through the membrane.

Each leaf is then sealed on three sides with glue, the fourth edge being attached to a permeate collection tube, or central tube. This central tube

is fitted with tiny holes, or perforations, which allow the clean water to pass from the permeate carrier into the central tube for collection. Next,

sheets of feed spacer are placed in between each of the membrane leaves, the number of which varies according to the element purpose and size.

The purpose of the feed spacer is to enhance turbulence and promote the membrane performance characteristics. After the leaves and feed

spacers have been properly laid out and glued, they are tightly and precisely rolled up around the central tube and then protected with either a

wrapped tape, fiberglass or durasan skin.

ELEMENT CONSTRUCTION OPTIONS

The following section highlights some of the numerous applications that membrane technology is utilized for. Successful application of

membrane technology is largely due to the numerous types of membrane construction options available. In this respect, desalt membrane

products are renowned for their variety of membrane type, feed spacers, permeate carriers, glues, skin wraps, and sizes. Element construction

will depend on both the environment in which the element will operate, and the purpose for which the element is functioning. Operating

environments often have varying pH, chlorine concentration, feed stream consistency, etc., and elements are chosen based on their rejection

characteristics.

For example: Some membranes reject most everything including salt, others just reject certain types of salt, while others must reject substances

as large as proteins. Feed spacers are selected based on their ability to promote turbulence and avoid fouling, and element jackets are selected

based on the environment. All in all, customers have learned to depend upon Osmonics technological prowess to solve most any fluid separation

objective whether it is achieved with existing, off the shelf products or  new, custom engineered ones.

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* Consistent filtration efficiencies from all seams thermally welded:

- Less frequent bag changes with increased surface area

- Higher productivity, faster bag “change outs”

- Semi rigid cylindrical design

- Easily crushed and incinerated

* Felt is a disposable, low cost material which is generally used for depth filtration because of its high solids loading capacity compared to

similar pieces of mesh fabric. The media is created by needle punching two layers of synthetic fibers together in a supporting scrim.

* Felt is manufactured with either a standard or glazed finish. A glazed finish, such as that on Ronak bags, is created by melting the outermost

surface fibers, producing a bond, which reduces the possibility of migration.

* All Ronak polypropylene bags are compatible with a broad range of corrosive fluids including organic solvents, oils, acids, and alkalies. An

assortment of filtration ratings is offered (1-200µ) to comply with all filtration requirements.

* Bags contain a molded polypropylene top with built in handle to quicken and simplify bag replacement. Tops have been welded to the felt to

circumvent needle holes.

* Determining pressure drop:

Step 1. µ rating, flow: Graph below shows pressure drops produced by one square foot of felt material based on various µ ratings and flow rates.

Step 2. adapt to bag size: Divide pressure drop by square feet of surface area in the bag of your choice.

Step 3. correct for viscosity: If viscosity of the liquid is heavier than water (1cps) multiply result in step 2 by the appropriate correction factor

found in the chart below. This should provide the correct pressure drop for the application.

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FEATURES

* 10, 15, or 20gpm (38, 57, 76lpm) flow rates * Heavy duty units for point of use and smaller filtration systems * Brushed 304 stainless steel

sump with a cast brass-nickel plated head * Recommended for high pressure and hot water applications not suited for Ronak plastic housings

* Accepts complete range of Ronak filter cartridges * All units offer a choice of either pipe plug or petcock in the bottom for draining he sump

* Maximum temperature 300ºF (149ºC) * Maximum cartridge diameter 3" (76mm)

The model ST-1 is a single cartridge filter ideal for filtering water at a flow rate not exceeding 10gpm (depending on cartridge selection).

The model ST-2 is identical to the ST-l, but requires two 9¾” (248mm) cartridges or one 19½” (495mm) cartridge to provide higher flow

rates and considerably greater dirt holding capacity for longer operations of the filter between cartridge change-over.

The model ST-3 is again identical to the ST-1 and ST-2 with even higher flow rate and greater dirt holding capacity than the ST-1 or ST-2.

Requires three 9¾” (248mm) cartridges or one 29¼” (743mm) cartridge.

* 28-125gpm (106-473lpm) flow rates * 304 stainless steel constructions, gray-silver epoxy finish * Accepts complete range of Ronak

cartridges: wound, fibrous, pleated and activated carbon * 4-20 cartridge capacities * Drains (¼”, 6.35mm) provided on clean and dirty sides

NOTES

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AQUARIUM UNIT FOR EXOTIC FISH

* This is a basic RO unit consisting of: - 5µ sediment inline filter with quick connector - Carbon inline filter - 50, 75, 100gpd membranes

- ¾” x ¼” feed valve - All tubing and fitting supplied * There is no reservoir * The permeate pipe should be connected to the fish tank * The

unit is ready to install

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Stage 1 : 5µ particulate filter: removes dirt, sediment, sand and other physical particles

Stage 2 : Activated carbon: reduces chemicals, such as chlorine, that may be in your water supply

Stage 3 : RO membranes: reduces 93%-98% of dissolved mineral salts and other contaminates in your potable water supply

Stage 4 : Post carbon filter: a polishing process that removes tastes and odors out of the water

RO is the most effective and economical way to provide your family with high quality drinking water. RO is the process by which water

molecules are forced by your household water pressure through a semi-permeable membranes. Contaminants are rinsed to the drain while

your high quality filtered water is stored in the holding tank.

Max dissolved solids : < 2000ppm, max manganese, < 0.05ppm

Temperature : 40-85ºF, max iron

Pressure : 40-125psi, hydrogen sulfide, must be present

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Filters

* Clear cover is easily removed for total cleaning * Flow capacity for entire system * Sediment is visible through the clear cover indicating

when the filter needs cleaning * Sediment is quickly and easily removed by opening the optional ball valve at the bottom of the filter cover

Ronak sediment filter covers are made of high impact polymer resin for maximum strength and durability. ½" MPT nipple on bottom of cover

for connection of an optional plastic ball valve for easy cleaning.

BODY

Ronak spin-down sediment filter bodies are PVC material in ¾" FPT, 1", 1½" and 2" slip x slip connections in and out. Bushings are available

to convert 1", 1½" and 2" slip x slip connections to female pipe thread.

The unique design of the sediment trapper element allows debris to settle in the bottom of the clear cover, trapping sediment away from the

screen. The new 1½" and 2" model elements make it easy to convert a standard spin-down filter to a sediment trapper by simply replacing the

element screens which are available in either polyester or stainless steel to suit your needs and can be ordered in various mesh sizes.

Ronak complete line of spin-down sediment and sediment trapper model filters make solid particle removal simple and economical.

* Centrifuge spin-down type sediment separation * Clear cover easily removed for total cleaning * Sediment is visible through cover * Reusable

polyester and stainless steel screens are available in various mesh sizes * Flow capacity for entire system * All molded non-corrosive materials

Available in 4 sizes : - ¾" FPT, - 1", - 1½", - 2" slip x slip connections in / out

Optional bushings available for 1", 1½" and 2" FPT

Spin-down model filters are ordered by size #, mesh size, when ordering stainless steel, denote with SS. For an optional flush valve add an F.

Example: ¾"-100 SSF is a ¾" filter with a 100 mesh stainless steel screen and an optional flush valve.

When ordering a sediment trapper model filter use size #, mesh size, ST designation and if stainless steel screen is desired, add SS.

For the optional flush valve, add an F.

Example: 1-100 STSSF is a 1" filter sediment trapper with a 100 mesh stainless steel screen and an optional flush valve.

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Ronak carries a complete line of water filter parts and accessories including:

* Filters * Filter & Membrane Housings * Components (fittings, shut off valves, faucets, flow restrictors, check valves, tubing, etc) for

residential RO Systems * Booster Pumps * Membranes of all Sizes * Components for Commercial/Industrial RO Systems * Multi Media,

Carbon, Sediment & Iron Filters * Delivery Pumps * Cleaning Chemicals, Test Kits and Monitors * UV Lamps * Ozone Equipment of all Sizes