Pure Cycle ®
Diffusion Dialysis Acid Recycling Systems
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Features & Benefits
Saving Money and Improving Quality With
Continuous, On-line Acid Purification!

Find out more about why these Companies are recycling acid solutions typically used for stripping, pickling, etching, or anodizing:

Pitney BowesGeneral ElectricUTC Pratt & Whitney
Black & DeckerDanaher Tool GroupPrinted Circuit Corporation
DevcoPrecision AnodizingGeneral Super Plating
ChemigraphicCentral Metal FinishingTeledyne Wah Chang
CaterpillarAAFCO B.F. Goodrich

With over 100 systems in the field, we've provided equipment to many companies with processes like yours. Pure Cycle's proven, patented Acid Recycling System is easy to install, inexpensive, and simple to operate. Paybacks can be as quick as six months! This system uses water and the principles of Diffusion Dialysis to separate usable acid from metal contamination that causes the acid to be discarded. Many users have not dumped their acid baths in over four years.

Semiautomatic systems start at $11,500, with 8 standard models rated at: 5, 15, 30, 60, 125, 250, 500, and 1000 gallons per day.

We believe our patented acid recycling system provides a long term alternative solution to your current acid waste generation processes.

The High Cost of Disposal

Wastes from plating and other wet processing operations are a permanent liability for the producer. With the Resource Conservation and Recovery Act (RCRA) and other legislation, the legal.financial and moral obligations imposed on waste generators have become a major area of concern. Pure Cycle's patented Acid Recycling System provides a logical way for metal finishing plants to deal with todays strict disposal requirements while conserving resources and saving money. Our systems are simple and economical to run Our unique technology efficiently recovers nitric. hydrochloric, hydrofluoric, fluoboric, methane sulfonic acid (MSA), sulfuric acid and mixtures of the above, from concentrated baths that usually must be discarded. The acid is returned to the process for continued use while only a dilute stream containing the bath contaminants and a small amount of acid requires any further attention. Recovering acids rather than destroying them avoids the costly problems of treatment, disposal, reporting and liability. The alternative Pure Cycle process improves manufacturing quality and maximizes production capacity. Our recycling systems utilize an advanced membrane separation technology known as diffusion dialysis (Fig 1). It was engineered and designed for the metal finishing industry to avoid concentrated bath dumping, a major pollution source, treatment expense, and liability.

Our proprietary design features an extended membrane area configuration that efficiently promotes the removal and concentration of the acid up to 95% of its original strength. The efficiency of a membrane to concentrate dilute adds in solution depends on the available surface area. Ion exchange membranes are sandwiched between spacers to form a series of cells. The spacers, in addition to supporting the membranes. provide the flow path and the hydraulic interconnection between the cells. Each membrane may be arranged hydraulically in a series configuration creating the opportunity for an extremely long flow path with enhanced membrane surface area. This extended membrane area combined with very low flow rates, results in a system that Is capable of efficiently removing acids to extremely low concentrations with almost no power consumption.

Pure Cycle Acid Recycling System in Operation

The used acid is metered through the system in contact with one side of an anionic ion exchange membrane. (see diagram.) Water is metered in a countercurrent fashion on the recovery side of the membrane. The majority of the acid migrates through the membrane into the water leaving contaminants such as heavy metal behind. The purified acid is directed back to the process tank. while the contaminant-laden spent acid stream goes to metal recovery or waste treatment for further processing. Fresh acid in proportion to the unrecovered amount is added to the bath to maintain the concentration within the correct operating window.

Pilot Testing Available for Guaranteed Performance

The highly resistant nature of ion exchange membranes to strong acids enables the system to handle a wide variety of mineral acids at high concentrations. Common metal contaminants such as copper, chrome, nickel, iron, and aluminum can be economically separated allowing the reclaimed acids to be used indefinitely. Each acid has a unique potential, this coupled with the chemical behavior of it's contaminants, determines the economies of recovery with diffusion dialysis. Pilot systems are available for on-site compatibility testing on your acid process chemistries.

Rugged Construction and Simplified Operation

Seven standard models of our Acid Recycllng System are available starting at 5 GPD to 1000 GPD, each complete and modularized ready for installation. Custom systems are also available. Operation is automatic and continuous and may run 24 hours per day, 7 days per week for best application economies. All systems contain the necessary high quality tanks, membrane stack, pumps, filters, and control Instrumentation. All components are preplumbed and prewired on a coated stainless steel frame. Noncorrosive, durable materials are employed throughout to withstand the harsh environment present in plating and wet processing plants. Operators will feel confident running any of our Pure Cycle systems because of the simplicity of the process and serviceability of the equipment. With few moving parts and low energy consumption, diffusion dialysis is a simple way and an ideal opportunity to Improve quality and reduce cost. Don't waste. Recycle!

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