Chapter 1 Introductiona. Historical Background of Dundee Precious Metal Tsumeb

The Tsumeb Complex was built between 1961 – 1962 and

commissioned in 1963 by Tsumeb Corparation Limited (TCL)

under mining giant Newmont Mining. It featured an

integrated copper and lead section, and smaller plants

that produced cadmium and arsenic trioxide as by-

products. Production officially started on March 3, 1964.

At that stage, the Smelter produced more than 3,500 tons

of copper and 6,000 tons of lead per month. By 1986 the

smelter was also producing sodium antimonite for export.

In 1988, TCL was taken over by the Gold Fields South

Africa and administered by Gold Fields Namibia (“GFN”).

Approximately six years later, the lead Smelter was

closed permanently. In July – August 1996, TCL’s mining

and smelting operations came to a standstill due to a

prolonged labour strike. This ultimately led to the

closure and liquidation of GFN in 1998.

Ongopolo Mining and Processing Limited (“OMPL”) gave

Namibia High Court an offer to take over the GFN’s mines

at Tsumeb, Kombat, Otjihase and Khusib Springs, as well

as the Smelter Complex in Tsumeb and it was accepted in

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March 2000. From 2000 – 2008, only the Copper section was

operational, the Arsenic plant was run on a small scale.

In July 2006 Weatherly Mining International acquired

OMPL, in December 2008 Weatherly suspended all the mining

operations because of a major decline in the world copper

price and only kept the Tsumeb Smelter going. The Smelter

was converted to a toll smelter at the beginning of 2009.

In March 2010, Weatherly sold the smelter to Dundee

Precious Metal Inc and shares with Weatherly retaining

all the mining assets.

Currently, half of the concentrates comes from Dundee’s

Chelopech mine in Bulgurial and the additional

concentrate is solicited from Peru, Greece, Russia,

Poland, Botswana and Democratic Republic of Congo.

Top-Submerged Lance (‘TSL”) furnace is at full

production. A new Oxygen plant, commissioned in February

2010 to increase the efficiency of the TSL, delivers 170

tons of Oxygen per day and increased the capacity of the

smelter dramatically from 120 000 tons of concentrates

per year to about 240 000 tons of concentrates per year.

At a moment, the Smelter Complex consists of five main

plants, Ausmelt plant, Copper plant, Oxygen plant,

Arsenic plant and Power plant that are all running at

their full potential, each with a specific purpose but

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working together to achieve a common goal, smelting

copper concentrates.

Electrical power for some of the smelters operations are

supplied by an on-site power plant.  The plant has the

capacity to produce 2.5 MW of power.  The power plant

uses the steam produced from the hot off-gases from the

reverb furnace in two waste heat boilers. The steam is

used to drive turbines in the power plant and generate

electricity.  Additional electrical power is drawn from

the national grid as required.

b. Dundee Precious Metal Tsumeb Visionand Mission

Our vision

A precious metal focused mining company that grows

through responsibly developing great assets and people.

Mission Statement

We acquire structure and finance, explore, develop and

operate our mining and processing assets. Our commitment

is to deliver excellence in sustainability and creating

value of all stakeholders

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Core Values

Our core values are fundamental to defining who we are as

a company and how we behave. Values guide our actions.

Everyone at Dundee is expected to support and and

demonstrate these values in our work.

Dignity and Respect

We are about people – their well-being, their careers and

development, and their day-to-day work experience. We

treat all colleagues fairly, listen to their input and

work with them to create solutions that respect both

individual needs and corporate interests.

Continuous Improvement

We are passionate about continuous improvement. We seek

out and execute operational practices that drive

innovation, speed to market, cost efficiency, technical

and professional excellence.

Transparency

We set and uphold the highest ethical standards and

business practices. Our dealings with employees,

governments, stakeholders and communities are open,

honest and transparent. We do what we say we will do and

fulfill our commitments. We hold each other accountable

for delivering results.

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Environmental Responsibility

We are leaders in promoting sustainable growth and

environment responsibility. We go beyond legislative

compliance to promote pragmatic environmental solutions

and practices in all of our operations

Safety

The health and safety of our employees and local

communities are paramount and enable us to be in

business. Safety can never be compromised.

Community Investment

We are about the quality of the communities in which we

operate. Our legacy will be to ensure we have helped

residents make the community a better place than before

we arrive on the scene. We have a strong corporate and

social responsibility to the communities in which we

invest.

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c. Dundee Organogram and location

Rick Howes

President and Chief Executive Officer

Adrian Goldstone

Executive Vice President

The geographically of Dundee Precious Metal Tsumeb is

situated about 4 km north of Tsumeb town and Tsumeb is about

430 km north of capital city Windhoek in Namibia.

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Hume Kyle

Executive Vice

Lori E Beak

Senior Vice

Michael Dorfman

Richard Gosse

Senior Vice President

Paul Proulx

Senior Vice President

David Rae

Senior Vice PresidentJeremy

CooperSimon Meik, PhD

Reuben Mills

Vice

Hans Nolte

Vice

Adrian Goldstone

Executive Vice

Dundee Precious Metals Tsumeb 

P.O. Box 936 

Smelter Road, Tsumeb, Namibia 

www.dundeeprecious.com

d. ObjectivesThe aims of this report is to outline the importance of

the industrial attachment, the skills acquired during the

attachment period, activities carried out, challenges and

the engineering solutions to all the problems

encountered. Compare the theory learned at school and the

hand on experience at the industrial attachment. Outline

tools and equipments mainly used at the attachment. All

that will be enclosed in this report.

e. Challenges and how I overcome themLike in any work place, challenges will always manifest

themselves in many ways, ranging from the work you do,

the people you work with, knowing the work place and

adopting to the work place.

At the beginning I had a lot of challenges, firstly

getting to know the place. There are mainly five Plants

around, thus excluding different offices in the premises.

I started working at the power plant, than copper plant,

after that I went to Ausmelt and lastly went back to the

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power plant. However , the daily works were not only

restricted to the same plant. One cane visits more than

one plant a day. Some plants are too big and have a lot

of places within them. That has been a problem find a

specific place the plant. This problem was not overcame

over one day all two, but as I started moving around I

got to know most of the places, however even after a

month there are still places I haven’t been too and some

I still have to.

In addition to that is getting used to the technical

words used at work, however this was not such of a big

problem because I learn to ask as soon as I hear a word

that I wasn’t familiar with.

The most challenging thing and of course the most

important of all was about the machines and tools we work

with to repair and to be repaired. One need to understand

how the machine work and this has been a challenge to me

through out. There was only one out to this problem, by

asking from the artisan I am working with and if I don’t

understand I than go to my supervisor and do the research

on that machine. Most of the time, I have to read about

the machines after work in order to get thoroughly

understanding of the machines. As a result, I got more

depth of most machines and the passion of my work.

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The hard thing of all is when my supervisor assumes I

know when it is even the first time for me to be exposed

to the situation. Even if I have to apply my engineering

skills it was still impossible for me to get it right,

let alone within the time interval. This just showed me

how much of things I need to know.

Other than that, it was a great experience. My horizons have been expanded.

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Chapter 2 The core activities of thecompanyThe core activity of this company is to smelt copper. The

copper concentrates are received by rail and off loaded at

the receiving bay. During the preparation of a charge for

the reverberatory or ausmelt furnaces the

necessary concentrates, fluxes and fuels are blended for

introduction into the furnaces. 

 Concentrates are blended with crushed reverts and various

fluxes to produce a furnace charge material. The charge is

fed into the furnace which is fuelled by pulverised coal.

The charge mix is smelted at approximately 1200 ºC to form a

slag and a matte (metal sulfides) phase. The molten slag,

which has a lower density and floats on top of the matte, is

removed from the furnace by skimming and granulated in

water. The slag is further processed at the slag mill if the

copper content is more than 0.6%. The matte phase is tapped

from the reverb furnace into ladles and transported to the

converters for further processing.

Hot off-gases pass through a waste heat boiler, which

recovers heat from the off-gases for steam generation.  The

steam is used at the power plant to generate electricity

while the hot air from the air heaters is introduced to the

Reverb furnace to aide in combustion. The off-gas is

further cooled in a spray cooling or conditioning tower to

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120oC before the cooled gas enters the baghouse where solids

(baghouse dust) and gas are separated when passing through

the glass fibre bags. Final cleaned off-gases are released

to the atmosphere via a high stack.  Dust from the baghouse

is either processed at the arsenic plant or dumped at

the waste disposal site which is under construction.

Off-gases from the Ausmelt pass through a spray cooling

system to cool it down to 120ºC before entering the baghouse

where dust is separated from gas before the cleaned gas

is released to the atmosphere via a second stack. Dust

recovered at the baghouse is taken to the arsenic plant for

processing.

Off-gases from the converter are cooled in a water spray

cooling tower to 120ºC  and pass through the converter

baghouse before being released to the atmosphere via the

same stack used for the reverberatory furnace.  Dust

collected in the baghouse is treated at the arsenic plant or

dumped into the waste disposal site.

Concentrates and other secondary material processed at NCS

are traditionally relatively high in arsenic.  The arsenic

passes through the smelter and is captured from the off-

gases in the baghouses.  Baghouse dusts with high arsenic

levels are used as feedstock into the arsenic plant. 

Baghouse dusts that cannot be processed in the arsenic plant

will be disposed of in the waste disposal site.

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The arsenic plant is used to produce arsenic trioxide from

dusts recovered during the smelting process. This is sold to

the third party.

That is mainly the processes that are taking place at the

company on a day to day basis.

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Chapter 3 Fault finding on Blower no

3 in the power plant.

There are 4 blowers at the

power plant. A blower is an

electrical device more like

a fan but it is designed to

produce a flow of gas at

higher pressure and with

larger gas volume flow.

This blowers are installed

to drive the hot gas

produced during the casting

process of copper. This gas

is used to generate

electricity. The Fig 1 and

Fig 2 show a blower no 3.

It is not working. In Fig

1, are the electrical

terminals, we were

measuring the lines voltage

and lines current to see if

there is imbalance. And see

if that is the reason why

the blower is not working.

This was the first time I

was exposed to three phase

system. I learned how to

measure the line voltage

and line current as well as

the phase voltage and

current.

U1V1 = 284V =U2V2 U1W1 =

275V=U1W1

V1W1 = 281V = V2W2

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Fig 1 Three phase terminals

Fig 2 Blower no 3 beingrepaired, at this stagewe are finding the

The results were correct and there

was no unbalanced voltage and

current.

We than went to inspect the

blower no 3 control panel. All the

wiring was good and we couldn’t

find any fault. As a last resort,

we tried to find the manufacture

circuit drawing of the machine. I

didn’t understand much of the

things for the first few

days. Eventual I learned how

the controls work. We found

out there was a conduct that

was not coming and that’s how

I came learn the use of

relays.

A relay is an electrically

operated switch. It comprises

a coil (of wire), a plunger,

and contacts, all housed together

within a case or body. Energizing

the coil creates a magnetic field

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Fig3

Fig

which moves the plunger. The

movement of the plunger causes a

moving contact to move toward (or

away from) a non moving contact. It

is the coming together of these

contacts ( making) or separation of

them (breaking) that has the effect

of switching. Wires or electrical connections internally

link the coil to the external connections to which the

operating supply will be connected Similarly internal

contact connections go to other terminals for connection to

the circuit being switched. The connections to a relay are

usually in the form of pins or blades in the base, which may

plug into a matching socket to which external wiring is

connected conventionally. Many smaller relays are soldered

directly into circuits, but for this machine they are

plugged in the circuit.

Through out, I learned how to service the blower and the

control panel. Finally a team from South Africa specialised

in control system came. I was than working with them. I

learned how to use a Sub-station Tester to dedect faults .

Using a Sub-station Tester, we dedected the faulty relays

and servesed the working relays. Fig 3, Fig 4 and Fig 5

shows the

relays we took from the control panels for all blowers.

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Fig5 Circuit drawing for blower control

Most of the time we install and fix light bulbs. Most

foroulecent bulb have ignators. I learned how to correctly

install light bulbs, suprisingly is the work of the ignitors

and how they work. Within the ignitor there is a coil that

make up small transformer. It transform 230V up to 400V,

that actually energize the electrons in the tube as the

current passes through the fillament starter. The fillament

starter is has a thermal switch that open when it got hot.

The tube contains Mercury gas, which is a good conduct of

electricity. As the mercury electrons get energized they

start to move around inside the tube and hence acting as a

conduct inside the tube, when that happen the thermoster

open and light is given out. White powder in side the tube

give it that foroulecent light. Fig 7 shows the inginator

circuit and fig 8 shows me and my colleaque replacing the

ignitor of the light bulb.

We also did installed and programmed the softstarter for

2.2kW motor. A softstarter is a programmable divice that

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Fig

help start the motor with low corrent drawn. If a motor is

started without a softstarter, it drows out a lot of current

and bigger motors may not even start. A softstarter allow

the motor to dradually start rotating until it reaches its

maximum speed, by so doing less current is drown as the

motor start.

In general, we have been dealing with electrical cables,

during the process I learn there are different cable sizes

and their categorised by the current and voltage they do

carry. The inslutor depends on the voltage that will go

through, high voltage means more inslution and high current

means thick cable.

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Chapter 4a.Skills and attitudes acquired

Professionalism and time management, this is the most attitudes I acquired. In engineering, time iscritical. The company can make a great lose if delivery was not on time.

Servicing electrical machines, motors, generators,

geysers and cranes.

Changing the direction of motors. Inspection of electrical machines, lights and

electrical connections. Awareness of the hazardous around and correct

measures to be taken in case of emergency. Using electrical equipment’s to test. Eg Multi

mater, sub-station tester etc. Analyzing problems and sequence reasoning to come

to a correct solution to a problem. Team work and communication within the staffs Wiring DPs

b.Conclusion

This was a great experience for me. I got the exposure

to most of the electrical machines and drives. I was

exposed to three phase system and learn how to measure

current and voltage in the three phase system. Most of

the systems are already in place and hence I didn’t get

exposed to designing of new project. The systems are

old and most of the drawing has been modified that make

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it hard to read and follow, more special when you have

to find a fault.

The company operates under harsh condition and most of the time we are exposed to hazards of different kind. However there are measures in place so that the safeties of workers are not compromised. As a policy, each one of us has to do a HIRA and get permission fromthe plant manager before you start working.

c.Recommendations

Engineering trainees at this company are not allowed towork on their own and most of the time I watch andobserve what others are doing. I recommend if at leastI can be given a project that I can run on my own withonly supervision. Most of the time I work with theartisans and they do not do the engineering work. Thistime around it was great because I have to learn howthings work, but I need to be involved in designing.

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References

1. 1.Theodore Wildi, Electrical Machines, Drives, and

Power System,2006, Laval University.

2. www.dundeepreciou.com

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