These sites incur the costs associated with off-site shipments of spent etchant and chemical purchases for both types of etchant. However, they can also realize the benefits from etchant regeneration and copper recovery from both types of systems. In the future, the facility plans to use the system for recovery of copper from all copper dumps in the facility. Ammoniacal etchant is regenerated for on-site reuse. After the copper is extracted from the spent etchant, additives are introduced to bring the ammonium chloride back up to the original specifications.
Copper is recovered from the spent etchant for off-site sale.
Copper is recovered by liquidion exchange as copper sulfate, which can be sold as liquid copper sulfate, electrowon into high grade copper metal, or crystallized into copper sulfate crystals. For every pound of copper in the spent etchant, four pounds of copper sulfate are produced. The system is not connected to the etcher itself, increasing the options for placement of the installation in the customer s facility. Costs and savings associated with installing the ARS unit are dependent on the operating conditions at each specific facility. Costs include the annual operating costs of electricity, spare parts, and chemicals, and the one-time expenditure for the capital equipment.