The Superior Lake process plant is designed to a nominal 44 tph of underground ore with high zinc grades and lower quantities of copper.
Scope of work
Primero completed a bankable feasibility study for re-development of the underground mine (by other consultants), process plant, site infrastructure and, licensing and permitting (by other consultants). All design elements were made suitable for cold climate. Historical test work and operating data were largely relied upon for process design. Historical power supply and building foundations were used as much as possible. Tight control over site water management and dust emission were included in the design to satisfy stake holder requirements.
Study deliverables were those suitable for a class 3 study:
- Process design including historical testwork review;
- test work management;
- PDC, MB and PFDs;
- Plant design suitable to support the formation of process plant and project CAPEX and OPEX, including mechanical, electrical, civil, structural and associated
- Procurement and project execution planning and documentation; and
- Study management for both the process plant and deliverables from external consultants for site wide infrastructure and underground mine redevelopment.
The Superior Lake process plant is designed to a nominal 44 tph of underground ore with high zinc grades and lower quantities of copper. The ore is crushed to P80 80mm via a primary crushing circuit and then conveyed to a SAG mill for milling to a target P80 75 µm. The copper circuit consists of rougher flotation, copper regrind circuit and two stages of cleaner flotation prior to dewatering via thickener and filter press. Zinc is recovered from the copper circuit tail via rougher-scavenger flotation, zinc regrind circuit and three stages of cleaner flotation prior to dewatering via thickener and filter press. Zinc and copper concentrates are each loaded into containers that are sealed prior to removal from the process plant building for dispatch. The tailings are thickened and pumped to the TSF or fed to the paste plant prior to being pumped underground. Water treatment is included for the zinc flotation process water and any water requiring discharge from the process plant.