POINT SOURCE ION EXCHANGE SYSTEMS

Remco Engineering P-SIX™ (Point Source Ion Exchange) systems are self contained units based on a unitized tank mounting frame constructed of polypropylene. These systems are designed for easy installation, good appearance, and low maintenance. Modular in construction, the systems are quickly repaired if the need arises.

Originally designed for a single tank overflow rinse, they are also applied to low (2-5gpm) flow streams in shops with segregated rinses. Usually one P-SIX™ is used for each metal to be recovered and a remote recovery module is used to reclaim the metal and prepare the column for reuse.

The system is in a lead/lag configuration with two ion exchange columns. They can be configured for either DI or chelated resin metal recovery. Either configuration will use the P-SIX regeneration module. In a chelated resin system, the first column fills with metal and is moved to the regeneration/reclaim module. The second column is moved to where the first one was and is reattached to the system. While the full column is being regenerated, the system runs on one column only. When the regenerated column is returned, it is placed in the lag (second) position.

In DI systems, the columns are switched out as pairs.

THE BASIC SYSTEM:
1. Duplex ion exchange columns with resin.
2. Feed pump, tefc motor with non-magnetic pump.
3. 20" depth filter
4. Diverter valve assembly
5. Acid or Caustic dosing bottle
6. Caustic or acid dosing pump
7. pH controller
8. Dual level controls, pump down and high alarm
9. 30 gallon polypropylene sump with support structure
10. Sample port between columns

Operation:

The P-SIX™ system is designed to remove metals from dilute rinse water streams and concentrate them for recovery. The system uses ion exchange resins to remove either cations (such as Copper, Nickel, Chrome +3, Cadmium, Lead) or anions (Cyanide, Chrome +6, Sulfate, Carbonate). When the system is configured with both cation and anion resins, the system provides DI water and is used to close loop rinses.

The rinse water is drained into the sump at a rate less than or equal to the capacity of the system (2 gpm standard). The rinse water is pH adjusted (optional) when necessary and pumped through the resin columns. The system consists of an non-metalic pump which constantly recirculates the solution through the diverter valve and back into the sump. A level control monitors the solution level and sends solution to the columns when the sump fills to the setpoint. (If the pH module is installed, the diverter valve is interlocked until the pH is at the correct point.) As the solution passes through the column, the ions in the rinse water are exchanged for the ions on the resin. In cation columns, the exchange ions are usually H+ or Na+ (acid or Sodium) and in anion columns the ions are OH- or Cl- (Hydroxyl or Chloride). A simple example is removing Copper ions from a dilute waste stream using a weak acid cation resin. The resin is prepared with Sodium ions at the exchange sites. When the copper ions pass through the resin, they are exchanged for sodium ions. The solution that was Copper sulfate is now Sodium sulfate and the Copper ions remain on the resin in the column.

The columns are in a lead-lag (series) configuration. The solution passes through the lead column where most of the copper is removed and passes through the second column where any residual copper is removed. When the first column becomes saturated, "breakthrough" occurs and higher copper levels are passed to the second column. A sample valve is provided for checking for copper breakthrough on the lead column. When copper breakthrough is detected, the lead column is regenerated while the lag column becomes the lead column and, temporarily, the only column.

Regeneration of a column is accomplished by washing the resin with a reverse flow of water to remove broken resin particles, followed by an acid rinse to extract the copper from the resin. The resin is next rewashed to remove the residual acid then conditioned with caustic soda (NaOH) to return the resin to a sodium form to prevent the pH of the rinse stream from dropping when the column goes back on line. A final rinse removes the residual caustic and reclassifies the resin. The column is now ready to go on line. These regeneration systems feature our POWER PURGE regeneration cycle for low regenerant and water usage.

Control System:

As the unit fills with rinse water, the pH probe located in the sump senses the pH and the pH controller adjusts the pH. When the pH is below the setpoint, the diverter valve is held in the recycle mode while the pH is being adjusted. As the level in the tank rises, it reaches the highest of the three level probes and the level control switches to the pump down mode. The system will pump down until the lower probe is reached. Upon reaching the low level probe, the level control switches into the recycle mode once again.

P-SIX™ SPECIFICATIONS

  Operational range:

pH 0-14
Flow rate: 2 gpm max
Effluent quality: Divalent cation leakage less than 1 ppm at design flowrate.

pH meter
Range 0-14
Accuracy 0.01 pH
0.1% mv Output

Relay 5 amps @ 115
2.5 amps
Isolated 4-20 ma Pump, main
Power 1/8 hp
Max flow rate 2 gpm
Motor TEFC
Phase Single
Material Noryl
Pump, dosing (solenoid)
Duty cycle, max 100%
Output 30 gallon/day
Main holding tank Approximately 30 gal
Dosing bottle 1.0 gallons
Columns 1.6 cu. ft. -3.6 cu. ft
Resins
Carboxylic (weak acid caion) Sulfate (strong acid cation) Amine (strong base, anion)
Chelating (iminodiacetic)
Power Requirements: 115 volts
15 amps

Options

  
Carbon filtration
High head pressure pump
DI setup with conductivity controller
Interlocks to conveyor systems
Flow monitor
Pressure switches/sensors
Microprocessor controller
Mini system with only DI bottles, pump and conductivity controller for DI recirculation.