Silver extraction from photographic waste Introduction:

During the photographic film processing, Silver leaches into the fixer solution (Sodium Thio-Sulphate) from the photographic film and forms Silver Thio-Sulphate complex ions. The fixer is considered exhausted after becoming silver-rich (7-10 gm/l), as it can no more serve the purpose of fixing the film in effective manner. Such exhausted fixer can then be processed to recover the Silver from it.Product: Digital Photo-lab Silver recovery machine

US Imagineering, Inc. is your source for quality silver recovery equipment and silver refining, serving the Silver Recovery needs of the Medical Imaging, Graphic Arts, and Photographic industries for over 20 years.

It is a member of the PMA (Photo Marketing Association) and DIMA (Digital Imaging Marketing Association)

Process:

There are 2 ways of recovering silver from photographic waste.

1) Electrolysis:- Current required is about 40 mA, voltage can vary from 72 V to 2 V depending on the concentration. The cathode is a steel plate preferably having a large surface area. (Note: the voltage is to be decreased as concentration of silver decreases or this will lead to deposition of silver sulfide which is black in color, hard to remove from the electrode and slows down the process as well)

The silver deposited can be scraped off and refined again by electrolysis in silver nitrate solution (pure silver rod as cathode and the silver from above process as anode apply voltage of 12 V and current of 200 mA). The silver obtained is 99% pure.

2) Metal displacement:- In this the soln is treated with iron wool or zinc dust (recommended). These metals displace silver and silver is obtained as a sludge. This has to be melted, made into a bar and refined by electrolysis in silver nitrate as told above. This process is faster but a bit complicated (u know melting the stuff and all is a pain in the neck!)

Technology:

It is a fully automatic silver recovery pumping system that desilvers bleach fix, fixer, and stabilizer directly from the processor’s overflow and simultaneously, can be used as a dumping station. By precision meter pumping the solution through the triple-segregated patented Multi-Media Cartridges, the solution’s silver content will be consistently and reliably reduced to below 5 ppm compliance requirements. This exciting new patented technology utilizes multiple and individual multi-media catalysts to remove the silver from solution without breaking down as quickly as in conventional steel wool buckets and columns. Less residual iron during refining produces much higher silver yields.

Operation:

ELECTRONICWASTECONTAINERFULL SENSORWITH AUDIBLEALERT

OPTIONALUSE DUAL2.5 GALLONWASTECONTAINERS

DOZENS OFVERSATILECONFIGURATIONSWITH OR WITHOUTCONTAINMENT TRAY

ELECTRONICELAPSEDPROCESSING TIMECOUNTER INTERNAL

HI/LOWAUDIBLEVOLUMEOPTION

VISUAL LEDINDICATORS1) Green - Power On2) Amber - Processing Effluents3) Red - Waste Container Full4) Red - Reservoir Full5) Red - High Pressure Alert6) Red - Spill/Leak Alert (optional)

OVER-PRESSURE LIMIT SENSOR FORTROUBLE-FREE SAFE OPERATION

OPTIONAL COMPACT 110%COMPLIANCE CONTAINMENTTRAY (125% ACTUAL)

CONVENIENTRESETTABLEELECTRONIC CIRCUITBREAKER

TRIPLECOMPLIANCECARTRIDGES

INSTANTLYREMOVABLECARTRIDGESERVICINGACCESS COVER

6-GALLONRESERVOIR WITH HIGHLEVEL ALERT FLOATSENSOR & AUTOMATICOPERATION SOLUTIONTANK SENSOR

MANUAL POUR IN TANKACCESS COVER