Pulacayo Project Feasibility Study - Apogee Silver

Pulacayo 1 000 t/d Phase I Feasibility Study - NI 43-101 Technical Report
090644-3-0000-20-IFI-100
17 RECOVERY METHODS
The Pulacayo mineral processing plant design is based on metallurgical test results
undertaken by various laboratories on behalf of Apogee Silver Ltd. Where the test work
results were unavailable, assumed data from similar projects were used. The plant has been
designed to process 1,000 t/d of polymetallic bearing mineral ores. The overall process plant
and unit operations therein are designed to produce base metal concentrates of lead and
zinc with silver reporting predominantly to the lead concentrate.
The processing plant will include circuits for conventional crushing, screening, clays washing
and screening, grinding, lead flotation, zinc flotation, concentrate filtration and storage,
reagents storage and handling, tailings storage and disposal facility, backfill, auxiliary
services, carbon columns to remove copper ions in solution and organic flotation reagents
from the recirculated process water.
The processing plant is a conventional design and comprises equipment of the type and size
that has been proven in the plants processing similar mineral ores in the industry.
17.1 Process Design Criteria
Apogee Silver Ltd. tasked TWP Sudamérica S.A. to design a process plant for the Pulacayo
project with a design capacity of 1,000 t/d. For the design, TWP used an availability factor of
86.2% for the crushing and milling areas. These design availabilities are fairly common for
current and recent projects at TWP.
The annual ore tonnage of 360,000 metric tons can be processed through the mill in
360 days.
A summary of the design parameters are given below in Table 17.1
Table 17.1: Process Design Basis
Parameter Unit Value
Ore Characteristics
Silver, Ag Design g/t 240
Range g/t 135.6 ­ 487.3
Mean g/t 302.3
Lead, Pb Design % 1.1
Range % 0.66 ­ 4.3
Mean % 2.28
Zinc, Zn Design % 1.92
Range % 1.34 ­ 5.96
TWP Sudamérica S.A. Av. Encalada 1257 Of. 801, Santiago de Surco Lima 33, Perú (51-1) 4377473
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