NRD/MRU/TP/1/91 22 November 1991
UNITED NATIONS
ECONOMIC COMMISSION FOR AFRICA
DEVELOPMENT OF LEAD AND ZINC RESOURCES IN AFRICA
Economic Comnussion for Africa Minerals and Energy Section Natural Resources Division P.O. Box 3001
Addis Ababa, Ethiopia
ACKNOWLEDGEMENTS
(i)
INTRODUCTION 1
EXECUTIVE SUMMARY 2
USES OF LEAD AND ZINC 6
LEAD AND ZINC OCCURRENCES 9
LEAD AND ZINC RESERVES 9
LEAD AND ZINC PRODUCTION TECHNOLOGY- 10
Mining and benefication 10
Primary lead smelting and refining 10
Environmental considerations 11
Zinc smelting and refining 11
Environmental considerations 12
Treatment of mixed lead-zinc ores 12
Processing of scrap i2
CAPACITIES FOR THE PRODUCTION OF LEAD AND ZINC
IN AFRICA
14
Lead and zinc mine capacities in 1984 14 Lead and zinc mine capacities in 1990 16 Lead and zinc refineries capacities in 1984 18 Lead and zinc refineries capacities in 1990 18 OPERATIONS OF THE AFRICAN LEAD AND
ZINC INDUSTRIES 20
Lead and zinc mine production 20
Trade in lead and zinc concentration 30 Refined lead and zinc production 30 Exports of lead and zinc metals 42 Consumption of lead and zinc metals 44 Main operating companies and shareholders 46 AFRICAN COUNTRY REVIEWS CONCERNING THE LEAD
AND ZINC INDUSTRIES 59
Algeria 59
Angola 59
Burkina Faso 60
Cameroon 61
Cote d'lvoire 61
Congo 6l
Egypt 62
Gabon 62
Kenya 6 2
Madagascar 63
Mali 63
Mauritania 63
Morocco 63
Namibia 65
Niger 66
Nigeria 66
Somalia 67
South Africa 68
Sudan 68
Tunisia 69
Zaire 70
Zambia 70
Zimbabwe 71
1. African Lead-zinc mines capacities (1984) 15 2. African Lead and zinc mining projects (1984) 17 3 African Lead-zinc refineries capacities (1984) 19 4 African Lead mine production (1980-1990 21 5. African zinc mine production (1980-1990) 22
6 African Lead and Zinc mines (1991) ^7 African refined lead production (1980-1990) 31 8; African zinc stab production (1980-1990) 32
9. African primary lead and zinc metallur- 34-36gical works (1991) 38-41
10. African secondary lead plants (1991) 11. African secondary zinc plants (1991) 12. African exports of refined
lead (1980-1990)
13. African exports of zinc
stab (1980-190)
14. African refined lead consumption (1980-1990) 15. African zinc stab consump-
tion (1980-1990)
16. Ownership of African lead 50-53
and zinc mines (1991)
17. Ownership of African primary ,1OQ1, 54-55 lead and zinc metallurgical works (1991) 54 bt>
18. Annual average prices of lead and zinc (1980-1990)
19. World Stocks of lead (1980-1990) 20. World stocks of
zinc (1980-1990) 0O
21. Namibian lead-zinc reserves (1987)
s
=5.
(i)
The work programme of the Economic Commission for Africa (ECA) in the sector of mineral resources calls for the periodic publication of technical studies on specific minerals which are considered to be important for the industrial development needs of the African region. These publications are intended to provide information to African governments, African intergovernmental institutions, African industries, international institutions, investors and other relevant institutions in order to enhance the development of African mineral resources to meet the needs of the African people and the world community.
The present study on the development of lead and zinc resources in Africa covers: the uses of lead and zinc, ^ lead and zinc occurrences and reserves, technology for lead and zinc production, capacities for the production of lead and zinc in Africa, operations of the African lead and zinc industries since 1980 including the main operating companies and shareholders, and reviews of individual African countries with lead and zinc resources and operating industries.
It is hoped that the various actors in the lead and zinc industries in Africa will find this desk study useful. The Economic Commission for Africa wishes to appeal to such actors to regularly supply data and information on African lead and zinc industries to ECA so as to enable the updating of this study at a future date. The present publication is available in the English language only and in limited copies.
EXECUTIVE SUMMARY
Uses of Lead and Zinc
By far the most important economic sectors which consume Lead and zinc are the transportation and construction industries respectively. Within the transportation industry lead is considered indispensable for starter batteries and is also the main material for storage and propulsion batteries. Within the construction industry zinc is used to galvanize steel for corrosion protection and the production of brass-
Lead and Zinc occurances
The two metals occur in association with each other and thus are generally produced by the same countries. Their resources are widely distributed around the world. However, within the African region in particular their development have been constrained by such factors as limited exploration coverage, lack of basic infrastructure and adequate transport facilities, and lack of investment resources. In addition, the lead and zinc industries in oil-rich African countries seem to be neglected possibly because the two metals are relatively very low priced compared to oil and
other metals.
Technology for lead and zinc production
Technology for lead and zinc production entails mining, benefication to obtain concentrates, and reduction to obtain refined primary metals. Refined secondary metal is also increasingly being derived from recycling of scrap especially in
the case of lead.
In order to avoid environmental degradation, the production of primary lead and zinc requires that associated sulphur dioxide emissions are converted to sulphuric acid which is an economic asset. Moreover, particularly, in the case of lead production, safety and healthy standards for workers have to be maintained.
Furthermore, toxic waste discharge standards exist. These environmental considerations are increasingly being internationalized, irrespective of country of operation.
African lead and zinc production capacities
During the decade of the 1980s, mine capacities for lead and or zinc were found in Algeria, Congo, Kenya, Morocco, Namibia, South Africa, Tunisia, Zaire and Zambia. Primary metallurgical capacities for the production of lead and zinc metals were available in Algeria (zinc), Morocco (lead), Namibia (lead), S.
Africa (zinc), Tunisia (lead) Zaire (zinc) and Zambia (lead and zinc). Capacity for the production of secondary lead metal was
also available in such countries as Algeria
SMrSSS o'f secondary zinc «U1 was
based in Egypt and s. Africa T.gad and Zinc production
Producers of mine lead in decreasing order of importance were
Morocco S Africa, Namibia, Zambia, Tunisia, Algeria and Congo.
On the other hand, African mine production of zinc generally
improved6fro* the base of.240 000 metric tons in 1980 (4% of world
total) to 313 000 metric tons m 1987 (4% of world «>«"'•
Thereafter the African mine production of zinc decl«ed^steadily
from 275 000 metric tons (3.9% of world total) in 1988 to 249 ooumetric tons in 1990 (3.4% of world total). The African producers
ofm\ne zTnc in decreasing order of importance were S. Africa,
Zaire, Zambia, Namibia, Morocco, Tunisia and Algeria.
Among the factors which contributed to African declines in lead and zinc mine production during the last decade included obsolete
materialise most probably because of adverse metals market
conditions and difficulties in financing the projects.
It is possible that during the decade of the 1990s African mine
production of lead and zinc could be expanded in such countries asBurkina Faso, Congo, Morocco, Nigeria, S. Africa, Tunisia and
Zimbabwe depending on improvements in international economic conditions and the availability of funds for improving old mines
and establishing new ones. In the longterm, other lea-zinc mines or African countries might come on stream depending on such additional factors as improvements in exploration and evaluation
improvements in physical infrastructure, improvements in political conditions in areas of political instability, and the increased
integration of the African mining sector with other sectors of
national and subregional economies.
of lead and zi^ concentrates
Mine production of lead and zinc in Africa during the 1980s was not all converted to refined metals in the countries of origin.
Some of the intermediate product from the mines was exported as concentrates. The main exporters of concentrates were S. Africa (lead) and Morocco, Namibia and Tunisia (zinc). South African lead concentrates were believed to have been destined to Japan and the European Community countries. Some of the zinc concentrates from Namibia were exported to S. Africa while the rest, together with those from Morocco and Tunisia were exported to the EEC countries.
During the 1990s export of African concentrates of lead and zinc are expected to increase resulting from the probable expansion of
regional mining capacity.
production of refined lead and zinc
The volume of African refined lead production (primary and secondary) remained somehow steady during the 1980s at an annual average of about 154000 metric tons (2.8% of world output). The African producers in decreasing order of importance were Morocco, Namibia, S. Africa, Zambia, Algeria, Tunisia and Nigeria. Over 69%
of the annual production of refined lead in the region was primary
metal.
African refined zinc production during the 1980s was of the order of 196 000 metric tons annually (about 3% of world production).
The African producers in decreasing order of importance were S.
Africa, Zaire, Zambia and Algeria.
With increasing mine output of lead and zinc concentrates in a country such as Morocco, new capacity of metallurgical works could be given consideration. Conversely, with decreasing mine output of lead and zinc concentrates in a country such as Zambia caused by depletion of ore reserves, consideration could be given to the possibility of toll-smelting and refining of concentrates from neighbouring countries. Additionally, because of such factors as the coining on stream of new mines in such countries as Nigeria (lead and zinc) and S. Africa (zinc), it is possible that such countries might consider establishing new primary metallurgical facilities in the 1990s. Furthermore, with increased metals recycling for both economic and environmental considerations, it is probable that during the decade of the 1990s more secondary lead plants will be established in the African region especially in countries with large consumption of batteries.
Exports of refined lead and zinc
Of the African production of refined lead and zinc raetals during the decade of the 1980s, an annual average of about 72 000 metric tons of lead and 80 000 metric tons of zinc were exported chiefly to the EEC countries. The main African exporter of refined lead was Morocco while relatively modest exporters of the metal were Namibia, Tunisia and Zambia. The main exporter of refined zinc was
Zaire with relatively minor contribution by Zambia. Some of the Zambian exports of lead and zinc metals were destined to countries within the Preferential Trade Area (PTA) for Eastern and Southern African countries. During the 1990s Morocco is likely to increase its volume of exports of lead metal while S. Africa is likely to increase its volume of exports of zinc. Intra-African trade in refined lead and zinc could be enhanced through the establishment of multicountry industries producing capital goods based on these metals and others for consumption in the African region.
Consumption of lead and zinc
African annual Consumption of refined lead and zinc during the period 1980 to 1990 averaged about 102 000 and 152 000 metric tons representing 1.9% and 2.3% of world total consumption respectively.
The level of consumption of the two metals indicate an apparent annual rate of imports of 20 000 and 36 000 metric tons of lead and zinc metals by the region respectively. The major consumer of lead and zinc in the continent was S. Africa, indicating the great extent at which the country has developed capital goods industries based on the two metals. Other relatively minor consumers of the two metals included in decreasing order of importance, Algeria, Egypt, Morocco, Nigeria, Tunisia and Zambia.
Ownership and operating companies in the African lead and zinc industries
In Algeria and Zaire both mining and metallurgical operations are state owned. In Morocco, Tunisia and Zambia both the State and private investment are employed in the lead and zinc mining industries. In the case of Morocco and Zambia the existing metallurgical plants are jointly owned by the respective States and private investors. Within Namibia and S. Africa private investors are employed in the lead-zinc mining and metallurgical operations.
Thus operating companies in the African lead and zinc industry range from state companies where state ownership prevails to private companies where ownership is wholly private. There is an increasing tendency for states to seek the participation of private investors in the lead and zinc industry in new projects as illustrated by countries such as Burkina Faso, Tunisia and Zimbabwe.
Prices of lead and zinc
Lead and zinc are relatively low priced compared to most other metals. Moreover, the prices of lead and zinc are influenced by such factors as demand for storage batteries (in the case of lead), and galyanised/brass/diecasting products (in the case of zinc);
commercial metal inventories (with producers, consumers, merchants and metal exchanges); metal exchange activities; and the strength
of the US dollar. The two most important price quotations for refined lead are the United States Producer Price (USPP) and the London Metal Exchange (LME). Price quotations for zinc are the USPP in the United States, the European Producer Price (EPP) in Europe, and the LME price widely used worldwide.
During the period 1980 to 1988 LME annual average cash settlement prices for lead were lower than the 1980 base of UK pounds 391.29 per metric ton. Commencing 1989 prices were higher than 1980 and reached a maximum annual average of UK pounds 459.78 per metric ton in 1990. Conversely, LME annual average cash settlement prices for zinc were higher throughout the decade compared to the 1980 base of UK pounds 327.42 . During 1990 the annual average cash settlement price for zinc at the LME was US$ 1520.27 per metric ton.
Deteriorating prices for lead during most of the 1980s reflected weak lead demand and high commercial metal inventories of over 400 000 metric tons yearly. Conversely, improvements in lead prices during 1989 and 1990 reflected rising lead demand and declining commercial metal inventories. The relatively strong prices for zinc during the 1980s were largely caused by declining commercial metal inventories which decreased from 711 600 metric tons in 1980 to 502 000 metric tons in 1990.
Concluding remarks
Because of market saturation in many developed countries the prospects for increased lead and zinc consumption in the 1990s seem brighter in the developing countries of the world compared to the developed countries. However, demand for the two metals might also be reduced in the developing countries due to poor economic growth
prospects.
Within the African region the development of the lead and Zinc industries could be enhanced where the outputs of the two industries were consumed by the domestic transport and construction industries. The development of African Lead and Zinc industries to supply the internal demand of the continent could be accelerated through: co-operation by African countries in joint investment in the production of the two metals, increased intra-African trade in lead and zinc concentrates and metals and expanded manufacture of end use products based on indigenous lead and zinc for consumption
in the region.
USES OF LEAD AND ZINC
Lead is used in (a) the transportation industry for batteries and solders (in vehicle manufacturing), (b) the construction industry for pipes, linings, insulating materials, roofs, lead coatings, radiation shields and solders, (c) capital goods industries as parts and linings in chemical processing equipment, pipes, lead
coatings and solders, (d) the electrical and communications
industries for cable sheathing, and (e) other industries such as the production of weights, ammunition, lead chemicals in glass, ceramics, paints and plastics.several changes are taking place affecting the use of lead in
many applications. These changes arise from efficiency in lead s uses and other considerations.Within the transportation industry lead is considered
indispensable (with today's technology) for starter batteries and
is also the main material for storage and propulsion batteries (1).However, although lead will probably be used for decades to come in battery manufacturing, improved technology in conventional battery production and alternative materials in new battery systems are likely to exert a negative impact on lead consumption in future.
On the other hand, interest in more powerful batteries (in developed countries) and increases in automobile consumption in developing countries could have a positive impact on lead
consumption.
Within the capital goods and construction industries, lead pipes and sheets can be replaced by plastics, galvanized steel, copper, brass and aluminium due to price competitiveness. With regard to the use of lead for cable sheathing in the electrical and communications industries, plastics and aluminium are increasingly
becoming material substitutes. Moreover, with the development of
optic fibbers used in telecommunications (where no cable sheathing is required), use of lead in this industry could be on the decline.Zinc is used in (a) the construction industry (as galvanized steel, brass, and rolled products for roofs, pipes and tubes, sidings, fittiAgs and electrical fixtures), (b) the transport industry (as galvanised steel for door panels and underbody parts of vehicles;
die-casts for grills, handles and mechanical components; and brass for vehicle radiators, valves and other parts), (c) rubber, paints and plastics industries (as zinc oxide in rubber vulcanizing; also in paints and plastics for protection against aging and solar radiation) and (d) other industries (as galvanized steel and die- casts for home appliances and office equipment; brass in tableware, furniture, ornaments, etc.; rolled products in battery shells, lithographic plates, zinc coins; and zinc chemicals for coating, copying paper, soldering, agricultural applications and
pharmaceutical uses).
Corrosion protection of steel by means of zinc coating is one of the main uses of zinc. In recent years, alloys of zinc and aluminium used for galvanizing steel and substitution of galvanized products by synthetic ones have had some reducing effect on the consumption of zinc for galvanizing.
Another very important use for zinc is in the manufacture of zinc
base alloys for die casting and to a lesser extent for uses such asTits, rodys, slush and sand castings. The main ™*£*°%™£r zinc die castings is the automobile industry (as door handles, inside door releases, window regulators, °utsld? ml^°"' carburettor bodies, windshield wiper ,components, loctas, racks
<?teerina column collars, and ornaments). Another market for zinc
die castings i^"builders' hardware (as doors and windows, locks and
kevs tools, cutlery, fittings, etc.). Zinc die castings are also usel in electrical components, domestic appliances and other equipment Because of recent emphasis on car weight reduction as well^s cost-competitiveness considerations, zinc die castings have b!en subject to strong competition from plastic components. Under the pressure of competition from plastics and aluminium and as a result of improvements in equipment for pressure die casting the
™n thickness of zinc die castings has decreased. inis
development his allowed zinc to compete favourably with the other
products.
Brass products constitute another important use for zinc. Brass
is alf»v.f jar ffif^"r.s;y^.bs"r fre
SsajfSi^s'TKi ?tsrs£ sees ^ j SSKmSSi 3Jw l.,v. «o™ dl.adv.nta,... wol.lly »!>•» "pair.
are needed.
Rolled zinc is another main zinc product. Zinc's excellent
corrosion resistance, formability and good appearance are its most important qualities for these uses. However, use °*-J")° s*ee*J££strip in the building industry for roofing, cladding and other componentsis facing competition from other materials such as aSumaid coated steel in many countries. Likewise, zinc
sheUs for dry cell batteries are facing competition from steel
shells.
Zinc oxide and other zinc chemical compounds are the other major use of zinc. Zinc oxide has many important properties such as high
cloacitv ?o ultraviolet rays, its ability to reduce the temperature required for rubber manufacturing, the property of ^Proving
electrical and heat conductivity of certain materials and high degree of reactivity which permits the production of a variety of
chlmicals. Almost one-half of the production of zinc oxide is used
bv tne rubber industry, in the vulcanization process. Zinc oxide
Ts allo ulel in the paint industry but in recent years this use has
been somewhat affected by the development of latex Pf"J™.„ ^vina
fndSy'is2^^^^^
fncreases in zine consumption in future will be strongest.
LEAD AND ZINC OCCURRENCES
Lead and zinc ores are often associated and occur in the same
and sphalerite (ZnS) are the most abundant ore minerals for the two
tl
p
metals.
There are three major settings for lead, zinc or lead and zinc deposits. Most important as far as production is concerned are the deposits in sediments, usually replacing limestone Controversy
over the origin of the solutions which deposited the minerals has
been very strong for years. According to one school, these
depositsTare of lydrothermal origin, that is there are igneous
rolks somewhere in the vicinity of the deposits and the lead- and zinc-bearing solutions migrated from the intrusions into and
replaced thi limestone. The second concept is that the deposits
wire rormed with the sediments or shortly thereafter by solutions
indigenous to the sedimentary formations (2).
The other types of occurrences are in veins and contact zones
where affiliation with igneous rocks is quite conclusive. These delolits are usually polymetallic, with the common associations
being lead, zinc, copplr, silver, gold, cadmium, and small amounts
of other metals.
LEAD AND ZINC RESERVES
World lead reserves as of 1990 were estimated at 70 million tons of metal content. World zinc reserves were estimated at 147 million tons of metal content. The United states Australia Canada and the USSR accounted for 63% and 50% of world reserves of lead and zinc respectively (1). Africa is estimated to possess 6%
of the world's lead reserves and 8% of the world's zinc reserves.
However, these figures are distorted due to such factors as ow intensity of exploration in developing countries and the practice in non-industrial countries of estimating reserves usually only
prior to mining development.
Thus in respect to the African region, sustained efforts in
systematic prospecting, evaluation and inventory of the region slead and zinc resources (as is true of all other minerals) is likely to enhance the ranking of the continent's mineral reserves endowment.
LEAD AND ZINC PRODUCTION TECHNOLOGY Mining and benefication
Underground mining is employed for most of the world's lead and/or zinc ores, because the depth and shape of the deposits do not permit extraction by surface mining.
Benefication involves crushing and grinding the ore to liberate mineral species. This is followed by ore benefication (or milling or concentration) through which, using the difference in physical characteristics among the constituents of the ore, waste materials (gaugue) are eliminated, and also when necessary, the valuable materials in the ore are separated. Flotation processes are more commonly used for lead and zinc ores. The process yields two or more products: concentrates, containing most of the valuable mineral, and a tailing containing most of the useless minerals
(gangue)
Lead and/or zinc concentrates are also produced as co-products with concentrates of other metals, or obtained as by-products during the benefication of ores mined mainly to obtain other
products.
Primary lead smelting and refining
Lead concentrates contain mainly galena, (PbS), but they also have some amounts of zinc, iron and copper sulphide, and usually, common impurities such as arsenic, tin, antimony, bismuth and silver. Common smelting methods for concentrates of base metals are either pyrometallurgical (use of heat), or hydrometallurgical (solution of the metal). Because lead is insoluble in sulphuric acid, which is the main solvent used in hydrometallurgical plants, all lead smelters employ a pyrometallurgical process. The lead concentrates are first oxidized (roasting) and then the oxides are reduced to metal (reduction).
During roasting the metallic sulphide and sulphur are oxidized.
During this process, part of the volatile metals are vaporised, and are contained in the off-gas together with sulphur dioxide and entrained particles. Most of the particles are recovered in electrostatic precipitator or in filters.
The lead oxide produced by roasting is subsequently charged to a blast furnace for reduction. The products of reduction are lead bullion and slag. Lead bullion contains a wide variety of metallic impurities which need to be removed by refining processes. In the
refining processes very pure lead and by-products such ^ zinc tin, arsenic, antimony, gold and silver are recovered. Slag from the blast furnace contains 10-22% Zn, and is often treated for zinc
oxide production.
Environmental gonsiderations
Environmental and health regulations at lead smelters require the control of sulphur dioxide emissions from primary smelters througn the installation of catalysts and plants precipitator where such emissions are converted to sulphuric acid. At secondary plants, the process employed is by flue gas desulphunzation. Another environmental restrictive measure for the industry relate to occupational safety and health standards governed by regulations for worker blood-levels and in-plant permissible exposure limits.
To comply with these, smelters require a combination of administrative controls and worker self-protection. Moreover, toxic waste discharge standards do exist. The environmental considerations outlined above are becoming increasingly internationalized, irrespective of country of operation.
ftinc smelting apd refining
Zinc concentrates consist usually of sphalerite, a zinc sulphide, and contain impurities such as lead sulphide, iron sulphide and gaugue minerals. Some trace elements are frequently present in valuable amounts, including cadmium, germanium, gallium, thallium and indium. The zinc content of the concentrates generally varies
from 48% to 62% while sulphur amounts to an average 32%.
Two main methods are currently in use to produce refined zinc from concentrates: pyrometallurgy and hydrometallurgy. More than 75% of the world's primary zinc production is carried on by hydrometallurgy, and this percentage is slowly increasing. Zinc pyrometalluray involves roasting - reduction of the concentrates followed by eiectrofurnacing or distillation, while hydrometallurgy involves concentrate roasting, leaching and electrolysis.
Sine obtained bv pyrometallurgical process is somewhat impure, ss it- contains over 1% lead and up to 0.5% cadmium. Therefore, after smelting, zinc refining is usually carried out_by liquation, or to obtain higher purity zinc, by fractional distillation.
The hydrometallurgical process also requires roasting in order to produce zinc oxide, given that zinc sulphide is not soluble in sulphuric acid. The roasted concentrate (calcine) is leachedwith dilute sulphuric acid which reacts with the zinc oxide, forming a zinc sulphate solution and a precipitate which contains impurities such as iron, aluminium hydroxides, arsenic, antimonium and
germanium.
After leaching, the solution containing impurities such as copper, cadmium, cobalt and nickel must be purified. Purification is generally realized in hot solutions, in successive stages during which each impurity is removed. The cements produced by purification are treated to produce materials rich in copper, cadmium or cobalt for further processing. The solution is piped to electrolytic cells, where zinc is electro-deposited on aluminium cathodes. The cathodes are periodically removed from the tanks and stripped of the zinc which is then melted in an electric furnace
and cast into slabs.
Environmental considerations
Sulphur dioxide gases produced during the roasting of zinc concentrates are the main environmental concern in respect to zinc smelters. Existing regulations in practically all countries require processes to treat these gases which result in the production of sulphuric acid.
Treatment of mixed lead-zinc concentrates
Some lead-zinc concentrates are not separable by flotation or other methods, because the dissemination of the sulphide limits flotation selectivity. In such case, the production of lead and zinc is achieved simultaneously through a process resembling fractional distillation, where vaporized zinc is recovered at the top and lead bullion recovered at the bottom of the Imperial
Smelting Furnace.
Processing of scrap
Secondary sources of metals originate largely from scrap and to a smaller extent from wastes, ashes, dosses and residues. Scrap includes new and old material. New scrap includes scrap generated during fabrication of products containing metals and which are used to recover their metal content at a plant of different location from the plant of generation, as well as defective or reject articles returned by purchasers to be reworked. Internal or run around scrap, which is remelted and consumed in the plant of generation, is not considered for statistical purposes. Old scrap includes worn, damaged or obsolete fabricated materials, usually discarded after serving a useful purpose, which are collected by refineries or manufacturers to produce metal in pure form or directly as a transformed product. The percentage of scrap in total world consumption for various wetals during the 1980s was:
aluminium 27%, copper 37%, lead 43% and zinc 24% (1).
The main source of secondary lead supply is storage batteries, although some smaller quantities are derived from cable sheathings, and tubes and sheets. For example, in the United States of America about 90% of lead scrap originates from storage batteries, with the
reminder arising mainly from cable sheath, pipes and sheet. Thus the potential availability of lead scrap is mainly related to battery consumption with a time life of 3-4 years. Recovery of secondary lead is usually carried on by secondary smelters.
The most important sources of secondary zinc are zinc in brass scrap and rolled zinc scrap. Zinc in brass scrap is the largest source of recycled zinc, but zinc metal is not recovered separately. Instead, it is recycled as brass (mainly from new process scrap) between users, brass makers or ingot makers. Rolled zinc scrap is easily recovered as new scrap from clippings or zinc sheet cuttings and old scrap from demolished buildings. Zinc die castings used in automobiles are also an important sources of secondary zinc. New scrap appears during alloy making and on the melting pots. Old zinc is recovered from dismantled cars, and the amounts collected are increasing as techniques are being developed to sort and separate non-ferrous metals from car scrap. Most secondary zinc is used without refining. However, some kinds of zinc scrap must undergo complete treatment from predefining to remove contaminants, to smelting and refining. The same primary zinc production metallurgical furnaces are used for the recovery of secondary zinc.
CAPACITIES FOR THE PRODUCTION OF LEAD AND ZINC IN AFRICA and zinc mine capacities in 1984
Within the African continent there were about 27 mines>
nroduced lead and/or zinc in 1984 (Table I). Of these mines, 75%
S lead mine capacity and 53% of zinc mine caP^£* wf^r^
from lead-zinc mines. Lead mine capacity was about 325
and Namibia) accounted for
African subregion (South Africa, Zambia and Namibia) accounted for 54"% of zinc mine capacity, followed by the central African subregion (Zaire and Congo) at 24.3%, and the north African
subregion (Algeria, Morocco and Tunisia) at 21.5*.
Worldwide (excluding the socialist countries) during 1984 there were about 337 mines which produced lead and/or zinc. Of these,
93% of lead mine capacity and 83% of zinc mine capacity derived from lead-zinc mines. Lead mine capacity was about 3-4 million
tons per year as compared to zinc mine capacity of 6.4 million tonsPer year. The major world capacities were in North America (USA and Canada), Latin America (especially Mexico and Peru), several
countries of western Europe and Australia.
T^ad-Zinr- nines Cqpacities
(thousand nitric tons per yeari
Lead Kine Capacity Zinc Mine Capacity Main Mining Coapanies (Parent Cospany or Major Shareholder)
1
Country
i Algeria
.
Congo J
Morocco
1 Nasibia
South Africa
Tunisia
Zaire
|| Kaabia
Total Africa World (Excluding socialist countries)
[I1 1 Africa
lead k zinc nines
10
12 35
63
97
7
17 242 3130
Lead Mines
1
79
-
1
483 229
—-
Total
11
12
-^—*^^—^—^
114
1
63 97-'
11
17
H 325 3359
9.7
■?-
Lead &
zinc lines
45
-
2 12
41
22
4
.i. ,i
1 44
_i 170 ■—
5305
1
zinc lines
3
_
1
67
5
76
J—I
1
1090151= ====
T
Total48
2 1
12
41
89
L
91
7644
1
6395321s =
5.0
_ —
Nuiber of Mines
4
1 7
3
2
8
1
1
271T"^
337■ksSESSSSS
'(Huaber of Mines, Lead capacity, Zinc Capacity)
Sonaren (4,11,48)
__ —
C. Toussit (1,50,0);
Sodin (1,19, 0)
__^^————————•
Iscor (1,12,28); Tsuaeb (2,51,13)
Black Mountain (Gold Fields, Phelps Dodge) (1,97,22); Prieska (1,0.67)
J .
Gecaaines (1,0,76)
1
20(31(1,17,44)I
_ '
=|==5=5====
■J
Source: The Lead and Zinc Industries, Horld Bank Staff Conodity Working Paper Ko. 22 (1990).
Lead and zinc mine capacities (1990.)
African lead and zinc annual mining capacities were expected to have increased by 25 000 and 128 000 metric tons respectively towards the end of the 1980s (1). Tunisia was expected to have contributed 18 000 metric tons of the lead mine capacity and the rest by South Africa, Namibia and Morocco. Tunisia and South Africa were expected to have contributed 69 000 and 50 000 metric tons of the zinc mine capacities and the rest by Namibia and Morocco. Total western world lead and zinc mine capacities were expected to have increased by 482 000 and 1.4 million metric tons respectively from the mid-1980s to the 1990s (Table 2).
Table 2 African and Zinc Mining projects 3-394
Country/Project
MOROCCO BRPH Boimadine HAHIBIA ISCOR Rosh Pina
S.AFRICA
Anglo and Gansberg
OTKISIA SOTEHI FejHassEx
OHM Bougrine SOTEJQ FejAhdoEx SOTEHI B. JabeuEx
TOTAL AFRICA ESTERS WORLD
Start up year
1988
1986
1987
1986
1988 1987
(up to 1990s}
Capacity, 000 tpy Lead
1 1
2
2
4
4
18
7
10
1
25 482
Zinc 3 3
6
6
50
50
69
4 50
6
9
128 1447
Source: The Lead and Zinc Industries, World BanX Staff Comodity Working Paper No. 22
(1990)
and ?j,pr. refin.?*"**"5 capacities (1984)
Tunisia and Zambia (Table 3)
Zaire and Zambia.
secondary lead smelter capacity of 56 000 metric tons
based in Algeria, Kenya, Zambia and Zimbabwe.
I-aart and gjnr. refir^r-iea capacities (1990)
mirina the period from 1985 to 1990 western world primary lead
sssa -sr^SS
would have been from the African region (1)
Table 3 African Lead-Xiac Refineries Capacities in 1984 (thousand letric tons per year}
Country
Algeria Kenya Morocco Naiibia
South Africa
Tanisia
Zaire
Zanbia Ziibabwe TOTAL AFRICA
WORLD (excluding socialist countries
Priaary lead Sielter Capacity
_
-
45 75
-
30
-
30
-
180
3283
5.5
Main Priaary Lead Sielter Capacity
-
-
Sfploab (45}
Tsuaeb (75)
-
Situnisia (3D) __,
-
ZCCK (30)
-
K* 4
K' 37
-
Secondary Lead Soelter Capacity
5 2
-
-
46
-
-
1 2 56
2842
2.0
Nmber of Secondary Sselting Companies
1 1
-
-
3
-
-
1 1 7
160
Primary Zinc Refinery Capacity
40
-
-
-
105
-
68 70
-
283 6089
4.6
Hain Priiary Zinc Refineries Capacity
S.Siderur(40)
-
-
-
Zinc Co.(105)
-
Gecaiines(68)
ZCCH (70)
-
N*. 4
»* 62
Source: The Lead and Zinc Industries, World Bank Staff Coaodity Working Paper Ho. 22 (1990).
OPERATIONS OF THE AFRICAN LEAD AND ZINC INDUSTRIES Lead and Zinc mine production
The African annual volume of lead mine production fluctuated between 245 000 and 295 000 Metric tons between 1980 and 1985.
There after the annual volume of production declined steadily for all producing countries to the lowest continental low of 172 000 metric tons in 1990. Worldwide, the share of African lead mine production was of order of 8.0% between 19080 and 1985. There after the African share of production declined steadily reaching a low of 5,4% in 1989. The African primary lead producers in decreasing order of importance were Morocco, South Africa, Namibia, Zambia, Tunisia, Algeria and Congo (Table 4) Lead production in the Congo ceased completely in 1986. Worldwide, lead mine production generally declined in the 1980s, from nearly 3.6 million metric tons in 1980 to just over 3.3 million metric tons in 1989.
The African annual volume of zinc mine production fluctuated between 240 000 and 314 000 metric tons between the period 1980 and 1990 (Table 5). The African volume of production represented an average of 4.2% of world zinc mine production between the period 1980 to 1989. The African producers of primary zinc were, in order of importance, South Africa, Zaire, Zambia, Namibia, Morocco, Tunisia and Algeria. Production of zinc in Zambia has been declining since 1988. Worldwide, zinc mine production steadily increased from nearly 6.2 million metric tons in 1980 to 7.3 million metric tons in 1987. Thereafter annual production remained
about constat at 7.1 million metric tons during 1988 and 1989.
Obsolete equipment, inadequate new investment and depletion of reserves seem to be factors which constrained the African mine production of lead and zinc during the 1980s. The anticipated increases in new lead-zinc mine capacities during the second half of the 1980s (Tunisia, South Africa, and Morocco) did not materialize most probably because of adverse market conditions, difficulties in financing the projects, technical problems etc.
Table 6 shows the main African lead and zinc mines as at the end of 1991. Of the 32 mines listed, 15 are lead-zinc mines, 3 are lead mines and 4 are zinc mines. The lead-zinc mines are in Algeria (2), Morocco (5), Namibia (2), South Africa (2), Tunisia (3) and Zambia (1). The lead mines are in Algeria (2), Morocco (5), Namibia (2), South Africa (2), Tunisia (3) and Zambia (1).
The lead mines are in Kenya (1) and Namibia (2). The zinc mines are in Morocco (1), South Africa (1), Tunisia (1) and Zaire (1).
The existing mines may be joined by new ones during the 1990s from countries such as Burkina Faso (zinc), Congo (lead and zinc), Morocco (lead and zinc), Nigeria (lead and zinc). South Africa
(zinc), Tunisia (lead and zinc) and Zimbabwe (lead and zinc).
Other future lead and zinc mines in other potential countries will
depend on such factors as improvements of international economic conditions, improvements in exploration and evaluation, improvements in physical infrastructure, improvements in political conditions in areas of political instability and the increased
integration of the African mining sector with other sectors of
national and subregional economies.
Table 4 African Lead Hine Production (Thousand aetric tons)
Algeria Congo Kenya Morocco Haiibia S. Afr.
Tunisia Zasbia Total Africa Itorld Total
\
I960 2.4 7.0
_
115.5 47.7 66.1 8.S 15.1 282.6
3583.2
7.9
1981 3.2 7.7
_
116.2 46.5 98.9 6.0 16.1 294.6
3447.0
8.5
1982 3.0 4.0
-
105.4 34.9 90.3 5.3 23.7 266.6
3556.5
7.5
=====
1983 3.0 4.0
-
97.3 33.8 87.5 4.9 14.6 245.1
3470.4
7.1
-
1984 3.6 2.5 0.5 100.6 42.6 94.8 4.1 18.8 267.0
3395.2
7.9
===
1985 3.8 1.0
-
106.8 48.6 98.4 2.5 22.5 285.1
3561.3
8.0
1986 3.5
-
-
71.8 37.1 97.8 1.9 24.3 237.4
3387.2
7.0
==
1987 3.5
-
-
73.6 29.5 95.9 2.1 22.8 227.4
3438.4
6.6
===
1988 3.6
-
-
70.1 22.8 90.2 2.2 21.4 210.3
3439.4
6.1
==2=
1989 4.0
-
-
64.7 23.9 78.2 1.7 12.3 184.8
3342.8
5.4 1990
1.5
-
-
66.9 20.7 69.4 1,8 11.5 171.8
3341.0 5.1
Source: World Bureau of Metal Statistics
Table 5 African Zinc Mine Production (Thousand netric tons)
Algeria Congo
Morocco Nasibia S. Mr.
Tunisia Zaire Zaibia Total Africa iiorld Total
\
1980 8.2.
-
6.1 25,4 81.7 9.0 67.0
«.9 240.3
6164.7
3.9 1981 10.7
-
7.9 36.4 86.7 8.2 75.6 39.7 265.2
6113.7
4.3
1982 11.1
-
12.3 35.7 90.5 8.4 82.1 52.5 292.6
6474.8
4.5 1983 12.1
-
7.6 33.2 137.3 7.5 74.7 41.6 314.0
6540.8
4.3 1984 14.6
-
11.6 30.6 103.0 6.7 68.4 41.3 276.2
6762.1
4.1
1985 13.5 2.0
14.7 31.2 96.9 5.6 67.9 50,6 282.4
6917.5
4.1
1986 14.0
2.0
12.2 35.4 101.9 5.0 81.3 50.9 302.7
6999.1
4.3
1987 13.0
10.7 40.1 112.7 5.9 74.7 55.9 313.0
7315.2
4.3
1988 10.0
10.8 32.4 89.6 9.0 75.7 47.3 274.8
7088.1
3.9
1989 10.0
-
17.3 39.3 77.3 9.7 75.0 23.5 252.1
7137.4
3.5 1990
6.0
-
20.6 37.7 74.5 9.6 79.0 21.1 248.5
7287.0 3.4
Source: World Bureau of Metal Statistics
Table6
NRD/MRU/TP/1/91 Page23 AFRICANLEADANDZISCMINES Country/Conpany/MdressNameofHineand location UfiEM SocieteNationals DeKecaerches& D'ExploitationsMkieres (SONAFEK) 127BoulevarddeSalah Bouakouir,Algiers KEHYA MineralMining Corporation(1965)Ltd.,
ElAtedHine, KherzeMoucef Mine,Western Algeria VitengeniMine, CoastProvince
HinetypeHearopened 0/G 0/G1952 1980 0/P1982
DailyKill Capacity (metrictons ofore)Lead
TypicalAnnualproductionKetalContent Sine (000metrictons)
Copper P.O.Box18273,Nairobi
NRD/MRU/TP/1/91 Page24 Country/(^any/addresstemeofMineMinetypeYearopenedDailyHillTypicalAnnualproductionMetalContent andlocationCapacity (netrictonsleadZincCoRier ofore) (000metrictons)(metric KR0CCO Erfoud,li/G1961N/A2.15.5- Centraled'AchatetdeBeni-Tadjit, developpeiaentdelaRegionHiniereTizi- deTafilaletetdeFiguigN'Firest, (CADETAF),Errachidia 7M.Zerktouni,B.P.86, Enachidiafcl:05723-25 Telex:41068 ConpaqnieKinieredeGuemassaDouarHajjarG/G1992N/A15601.4 (OB), 52,AvenueBassanII,Casablanca Tel:20-06-70,Telex:21859 SocietedeDeveloppementduCuivreBou-Kaadke,D/G1992N/A4.72.3- del'Anti-Atlas(SODECAT),Errachidia 5-7,ChariiMoulayHassan, Rabat,Tel.248-04 Telex:32871
Country/Co^any/MdressNaeofNineandNinetype locationYearopened SocieteKinierede DjebelAouai(Slft), 64RueAIHourtada, casablanca, Tel:25-27-17 Telex:210065 SocieteKinierede Tenuous(SONUS), 9RoeXurillo, Casablanca Tel:25-73-25 Telex:21720 CoapagnieMinierede Touissit(C.H.T), 5RueIbnouToufail, Casablanca, Tel:25-96-05 ■telex:21713 DjabelAouas,C/G Neknes
NRD/MRU/TP/1/91 Page25 DailyMill Capacity (retrictons ofore) N/A
Typical Lead (000 9.4
AnnualproductionMetalContent ZincCopper metrictons) 2.7 A.Aguert,AzilalD/G 1982N/A Touissit,OujdaD/G1975117051
NRD/MRU/TP/1/91 Page26 Country/Cmpany/ttdressRareofKineandMinetypeYearopened locationDailyHill Capacity (netrictons ofore)
TypicalAnnualproductionKetalContent LeadZinc (OGOnstrictons]
Copper (iwtric KMBIA IKORZinc(Pty)Ltd., PrivateBag, RashPinah, Saiibia9000 Tel:063342 Fax:(063342)145 Telex:56443 GoldFieldsKaaibiaLtd, P.O.Box40, Tsneb, Naaibia9000 Tel:(0671)3115 Fax:(0671)3710 Telex:680 ZincandLead (Saibia)PtyLtd., P.O.Box617, Tel:(0641)2916 Fax:(0641)2481
toshPinahMine, Aiis KosbatMine TsmebKine ZincandLead Mines, SvaXopund
D/G19691650 D/G D/G1962 19081350 1800 D/G1969250
1038
Country/Conpany/MdressSansofMineandlocationSinetype
NRD/MRU/TP/1/91 Page27 YearopenedDailyMill Capacity (metrictonsofLead ore)
Typical (000
Annual Sine metric
production r tons)
(fetal :opper SOUTHMICA BlackMountainMineralDevelopment Co.(Pty)Ltd., GoldFieldsBuilding,75FaxStreet, Johannesburg,2001 Tel:0116399111 Fax;Oil6322102 Telex:450044 PrieskaCopptrMines(Proprietary) Ltd., 56MainStreetJohannesburg, Transvaal Tel:0116349111 Fax:01165340038 Telex:486087 ShallSouthAfrica(Pty)Ltd., KetalsDivision,ShellHouse,51 PleinStreetJohannesburg,2001 Tel:0117174111 Fax:0117178001 Telex:4-22312
BlackMountainMine, fcggeneys,Districtof Namaqualand,Northcape. PrieskaMine(Pty}Ltd. Copperton,Districtof Prieska. PeringMines,Reivilo, DistrictofVryburg.
0/G198036007530 D/G197313 0/P1986350035
NRD/MRU/TP/1/91 Page28 Country/Conpany/Address Tunisia
NazeofMineand locationMinetypeYearopened SocieteTunisienne d'ExpansionHusiere (SOTEKIS.A.) AvenueMongiSlim,Le Kef CcmpagnieXisieredu NorctOnest 9RueDalton,1002Tunis Tel:286586 Telex:12442
ElAfchouat BoujabeurSine, KlaatSenas Fed]ElAdouniHine, LeKrib FejBasseneMine, Ghardisaou
U/G LeKr 0/G 0/G 0/G
1896 1897 1814 1899
DailyMill Capacity (metrictons ofore) 240 200
Lead 0.6
TypicalAnnualproductionMetalContent Zinc (000metrictons) 2.1
Copper 9.6 3.2 3.5
(metric
Country/Cocpany/MdressKaneofHlneand locationMinetypeYearopened ZHRE LaGeneratedesCarieres etdesMines (GECAHIffiS), B.P.450 Lubmbashi,Shaba Telex:21207 2WB1A ZaibiaConsolidated CopperMinesLtd. (SMI), P.O.Box30048, Lusaka Tel:01218033 Telex:ZA44540
KipushiMine,Shaba KotweMine,KabveD/G
1926 1905
NRD/MRU/TP/1/91 Page29 DailyMill Capacity (metrictons ofore) 3150
Typical Lead (000
Annual Zinc metric 70
production tons}
MetalContent Copper 45 9501035 Source:WorldDirectory:LeadandZincMinesandPrkaryMetallurgicalftrks;InternationalLeadandZincStudyGroup,August1991.
Trade in lead and zinc concentrates
During the 1980s the main African exporters of lead and zinc concentrates were South Africa in the case of lead concentrates and Morocco, Namibia and Tunisia in the case of zinc concentrates.
South African lead concentrates are believed to have been destined to Japan and Western Europe. Zinc concentrates from Namibia were exported to S. Africa and western Europe. Morocco and Tunisia exported their zinc concentrates to western Europe. During the 1990s exports of African concentrates of lead and zinc are expected to increase resulting from new mines in such countries as Burkina Faso (Zinc), Morocco and Tunisia (lead and zinc).
Refined lead and zinc production
The volume of African refined lead production (primary and secondary) remained somehow steady during the decade of the 1980s at an annual average of 154 000 metric tons. This annual average volume of production represented 2.8% of world refined lead production. (Table 7) The African producers of refined lead in decreasing order of importance were Morocco, Namibia, South Africa, Zambia, Algeria, Tunisia and Nigeria. The primary refined lead producers were Morocco, Namibia, Zambia and Tunisia. Tunisia's production of primary refined lead ceased in 1986. Production of refined lead in South Africa, Algeria and Nigeria was wholly secondary metal. Some small quantities of secondary refined lead were also produced in Morocco, Tunisia and some other African countries. Over 69% of the annual production of refined lead in the region was primary metal. Worldwide, refined lead production remained steady at nearly 5.4 million metric tons per year during the period 1980 to 1990. Thereafter world refined lead production increased some how steadily, reaching the highest volume of over 5.8 million metric tons in 1989.
Table 7 African Refined Lead Production
(Thousand letric tons) (Priaary plus secondary)
Source: Sorld Bureau of Metal Statistics
