What are the processes for developing a new mine in

Question

School of Science, Information Technology and Engineering

1. What are the processes for developing a new mine in Australia? Give your answer as per your geographic location.

2. What are strategic risks? How would you manage these risks?

3. Define short, medium and long term planning?

4. Discuss some of the factors that an engineer needs to account for when planning a mining operation.

5. What techniques of pit optimisation are available?

6. Define the following in relation to network techniques (CPM and PERT)
a) Earliest start time
b) Latest start time
c) Earliest finish time
d) Latest finish time
e) Slack
f) Float

7. Discuss the floating cone process.

8. Describe three problems with regard to the application of the floating cone technique. What are the positive aspects of the floating cone technique?

9. Summarise the steps in the Lerchs-Grossmann 2D algorithm

10. Define the terms:
a) Project year
b) Production year
c) Calendar year

11. Summarise the basic concepts behind Lane's algorithm

12. A project is defined by the list of activities detailed in Table 1.
a) Draw the network as an activity on the arc network
b) Find the critical path
c) Find the slack for each activity

Table 1

Activity	Immediate predecessors	Duration days
A	-	3
B	-	4
C	-	3
D	C	2
E	B	1
F	A	5
G	B	2
H	B	3
I	C	11
J	D, E	3
K	F, G	1
L	K	4
M	J, H	4

13. The network shown in the next diagram is to be used in the planning of the installation of an underground crusher station. Determine the total project time and the critical path.

14. Cut-off Grade

Following are the variables for choosing the "Optimum Cut-off Grade":
M = maximum amount of material that the mine can produce in any given time (mine capacity)
C = maximum amount of ore that can be put through the concentrator in any given time (mill capacity)
R = maximum amount of final product that can be produced in the given time period
(production capacity)
m = mining costs, $/t of material mined c = concentrator cost, $/t of ore milled r = smelting, refining, packaging, insurance cost, $/kg of final product f = fixed cost
s = selling price y = recovery
T = length of production period
Q_m = quantity of material to be mined
Q_c =quantity of ore sent to the concentrator
Q_r = amount of product actually produced over this production period

A. Using these above variables, develop the basic equations for

a) total cost, Tc

b) revenue, R

c) profit, P

B. Develop the equations for cut-off grade assuming that

a) mining rate is the governing constraint

b) concentrating rate is the governing constraint

c) refining rate is the governing constraint

15. Define the following terms used with respect to the Lerchs-Grossmann 3D algorithm

a) Directed arc

b) Edge

c) Weight

d) Node

e) Graph

f) Directed graph

g) Sub graph

h) Closure

i) Maximum closure

j) Circuit

k) Chain

l) Cycle

m) Path

n) Tree

o) Root

p) Branch

q) Twig

16. DESIGN PROJECT

The following describes a selection of mineral deposits. The candidate (Note: choose only anyone) is required to select a suitable mining method for the deposit based on the information given and to describe the mining system in detail. For whichever mineral deposit is selected, the candidate should include in their answer the following as required:

1. Describe suitable surface connection(s).

2. Detail development requirements

3. Detail Production requirements including a full description of the method selected.

4. Number of production unit's required/rate of production.

5. Describe loading/haulage requirements

6. Equipment

7. Briefly describe ventilation/drainage/power requirements

8. Personnel

9. Safety

10. Detail permitting and other requirements as required by the local regulator (students can select which jurisdiction the mine is located in from any Australian state or territory)

Students should also report on other salient points as required by the mining system. For economic analysis, use current market prices in A$ for the commodity as required. Accurate costings are not an essential aspect to the project but some notional costings should be undertaken to illustrate the viability of the method detailed.

UNDERGROUND MINING PROJECT

A massive silver/lead/ zinc deposit approximately 250 m in width and 1,500m long ranging in depth from 300m below surface to 900m below surface. Angle of dip is 70°.

SURFACE MINING PROJECT

A copper-gold-silver mine is located in a desert at an elevation of 3,050 m above sea level. Production is 46.9 Mt/y of sulphide ore grading 1.9% copper, containing 776,400 t of copper, 129,000 oz of gold and 3.28 Moz of silver.

The deposit is related geologically to three porphyry bodies intruded along a major fault system. Primary hydrothermal sulphide ore grades at between 0.2% and 1% copper. Subsequent weathering and uplifting created a barren, leached cap, up to 180 m thick, over a high-grade supergene enriched ore, both overlying the primary sulphides. Primary sulphide mineralisation includes pyrite, chalcopyrite and bornite, with covellite and chalcocite in the enriched zone. Some areas contain significant oxide copper oxides overlying the sulphides.

Proven and probable reserves estimated at 1,990 Mt grading 1.23% copper. Initial mining reserves totaled 662 Mt grading 2.12% copper. The stripping ratio will average around 1.7:1 over the full life of the project.