Zylon™ Backwash Filtration System One-Step Brine Polishing Without Pre-Coat Zylon™ Backwash Filtration System One-Step Polishing without At the heart of the Zylon System is the The Zylon System combines the latest Pre-Coat ultra-high-efficiency GORE* Filter Sock. filtration materials and hardware Pall’s Zylon™ Backwash Filtration Pioneered by W. L. Gore & Associates technologies to help ensure long-term System is the most cost-effective more than 25 years ago, this expanded performance and trouble-free system for one-step brine polishing polytetrafluoroethylene (PTFE) media operation. You’ll benefit from Pall’s without pre-coat available today. You has been successfully used in industry leadership in filtration, can replace costly clarifiers, sand thousands of applications. It offers separation, and purification, as well as filters, and pre-coat systems while still excellent filtration to the sub-micron Gore’s 40 years of experience in producing crystal clear brine with our level and is exceptionally easy to clean. expanded PTFE membrane technology. proven solution (See Figures 1 and 2). The result is the most efficient brine clarification system available today.
Figure 1: Conventional Brine Treatment
A conventional NaCl or KCl brine treatment process is complicated. Brine is processed through as many as six steps before it is ready for the electrolyzer. Using clarifiers, sand filters and a pre-coat systems increase capital and maintenance costs.
Figure 2: Pall Zylon System for Brine Treatment
The Zylon System delivers high purity brine to your downstream process while it eliminates the need for clarifiers, sand filters, and pre-coat systems. The result is potential capital savings of approximately $3 million.
Approx. Cost** TYPICAL RELATIVE PRECOAT COST CAPITAL COST FLOOR SPACE (Purchase, Handling, Disposal) Clarifier $2.0M 100% 100% 100% Set of sand filters $1.3M
Pre-coat system $1.9M 50% Total for conventional brine treatment $5.2M
Total for Zylon System $2.0M 25% Capital savings (approx.): $3.2M 0% * Gore is a trademark of W.L. Gore & Associates Conventional Zylon Conventional Zylon Conventional Zylon ** Costs for a typical system with a flow rate of 1000-1200gpm Brine System System Brine System System Brine System System System Components Next, a precise volume of filtrate in the The Zylon Backwash Filtration System dome is forced into the filter candles consists of filter support tubes covered by instantly expanding air from a with tubular membrane filter elements. separately installed air tank. These filter elements are mounted in a tube sheet clamped between the This reverse flow, or back pulse, causes flanges of the top dome and the the flexible filter socks to expand and vertical filter tank. completely removes the filter cake from the membranes. Continued back-flow The lower part of the filter vessel has flushes the tubular membrane filters, a coned bottom designed to densify regenerationing the media. solids and minimize brine loss to waste. After backpulsing, the solids are The filter dome and filtrate outlet are concentrated and collected in the designed to provide optimal back- conical bottom of the filter vessel. The Figure 3 washing pulse and volume for effective highly concentrated sludge is purged These photomicrographs compare the expanded PTFE membrane (top) to a heavily calendered and reliable cleaning. from the vessel in a controlled manner woven cloth (bottom) of similar permeabilities. that eliminates brine waste. Filtration Process Directly from the treatment tanks, brine Featuring GORE® Filter Socks enters the feed zone of the filter shell supported by a unique, patented, below the tube bundle. The Filtration system enables true one- molded support element comprised step brine filtration. Membrane filter of chlorinated polyvinyl chloride In a Zylon filter vessel, the brine passes socks bring the benefits of self-cleaning (CPVC) (Figure 4) designed specifically through the tubular membrane filters. membrane filtration to large-scale for brine filtration. Filtered brine flows upward through industrial filters. They combine the fine the filters to the dome. Suspended particle removal properties of solids that are detrimental to the ion membranes with the durability of high- exchanger units are collected on the strength felts. Additionally, the flow membranes as filter cake. Polished rate is equal to or higher than brine exits the filter on its way to the conventional filter media. ion exchange system or holding tank. The filter socks consist of expanded Cleaning PTFE membranes laminated to strong During filtration, the pressure drop felt supports. Filtration takes place on builds across the filter as particulates are the membrane surface, effectively removed from the brine stream. When removing submicron particles. The the pre-determined set point is reached, membrane has a micro-porous structure the inlet and outlet valves are closed. (Figure 3). The porosity is controlled, permitting the manufacture of The filter vessel is partially drained in membranes to fit specific filtration a controlled manner to prepare for requirements. The result is fine particle cleaning the membranes. retention and excellent cake release. The filter socks are installed over and
Depth vs. Surface Filtration
Depth filter media, GORE expanded e.g. needlefelt PTFE Membrane
The GORE expanded PTFE membrane retains particles on the surface of the filter sock. Figure 4: Pall Zylon Backwash Filtration System with molded support elements. Exclusive Features and Benefits GORE filter socks— Summary The unique characteristics of GORE The Zylon System produces ultra-pure Eliminate Clarifiers, Sand Filters, and filter socks include uniformly fine pore brine without the use of pre-coat Pre-Coat Systems size and a non-stick PTFE surface. The systems, clarifiers, and sand filters. The The Zylon System can save you millions socks enable one-pass submicron systems can save you hundreds of of dollars by eliminating the need to filtration with efficient in-place cleaning. thousands of dollars in capital and purchase and maintain clarifiers, sand maintenance costs while continuing to filters and pre-coat systems. Field Support— protect down-stream systems. The Pall Field Service Team provides Reduce Waste Discharge— worldwide support, so help is just a To learn more about the Zylon System Conventional pre-coat brine polishing phone call away. and to arrange for an evaluation of requires at least one pound of filter aid your brine stream, call Pall Corporation for every pound of solids removed. Simple, Efficient, In-Place Cleaning— at 516.484.5400. Outside New York Eliminating the pre-coat means reducing Controlled back pulsing and patented state, call 1.888.873.7255. Or visit our solids discharge to your waste treatment element configuration ensures that Web site at www.pall.com. plant by more than 50 percent. 100% of the filter media is regenerated.
Proven Technology— Tolerates Upsets— Pall Corporation is the worldwide The Zylon System accommodates leader in brine purification, supplying upsets in flow or solids concentration both precoat and non-precoat of the brine with no change in filtered backwash filter systems. Dozens of brine quality or long-term media chloralkali plants currently use non- blinding. precoat, backwashable expanded PTFE membrane filter technology. Patented Support Tube Elements— The unique design of the Zylon CPVC Zero Bypass— filter elements ensures equal flow The absence of pre-coat means there’s distribution, high flow rates, and no chance for filter aid bleed through. optimal cleaning. They are easily inspected and replaced. Minimal Maintenance— The one-step Zylon System eliminates Greater Capacity— moving parts, filter-aid holding and Eliminating the pre-coat step means mixing tanks, metering pumps, and that the filter is online longer, enabling extra piping. it to process more brine.
New York - USA Visit us on the Web at www.pall.com 1.888.873.7255 toll free in the USA Pall Corporation has offices and plants throughout the world in locations including: Argentina, 516.484.5400 phone Australia, Austria, Belgium, Brazil, Canada, China, France, Germany, Hong Kong, India, Indonesia, [email protected] Ireland, Italy, Japan, Korea, Malaysia, Mexico, the Netherlands, New Zealand, Norway, Poland, Puerto Rico, Russia, Singapore, South Africa, Spain, Sweden, Switzerland, Taiwan, Thailand, United Kingdom, United States, and Venezuela. Distributors are located in all major industrial Portsmouth - Europe areas of the world. 023 9230 3303 phone 023 9230 2509 fax [email protected]
© Copyright 2004, Pall Corporation. Pall, and Zylon are trademarks of Pall Corporation. GORE is a trademark of W.L. Gore & Associates. ® Indicates a trademark registered in the USA. is a service mark of Pall Corporation.
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