In 2006, for example, the leading producers of cobalt ore were the Democratic Republic of the Congo 41 percent, Zambia 12 percent, Australia 11 percent, Canada 10 percent, Russia 8 perce
Trang 1cially regarding oil and gas production The 1990
reauthorization established coastal nonpoint source
pollution control plans and required the
Environ-mental Protection Agency to establish uniform
na-tional guidelines for controlling nonpoint source
pol-lution in coastal areas The act was further amended
in 1996, 1998, and 2004 to regulate aquaculture
facili-ties and to research the effects of algal blooms and
hypoxia
Jerry E Green
See also: Coastal engineering; Land management;
Land-use planning; Land-use regulation and control;
National Oceanic and Atmospheric Administration;
Population growth
Cobalt
Category: Mineral and other nonliving resources
Where Found
Cobalt is widely distributed in the Earth’s crust in
many ores, but only a few are of commercial value; the
most important of these are arsenides and sulfides
The world’s major sources are in the Democratic
Re-public of the Congo, Australia, Canada, Zambia,
Rus-sia, and Cuba
Primary Uses
The largest use of cobalt is in superalloys, alloys
de-signed to resist stress and corrosion at high
tempera-tures Other important uses are in magnetic alloys for
motors, meters, and electronics and as a binder in
ce-mented carbides and diamond tools
Technical Definition
Cobalt (abbreviated Co), atomic number 27, belongs
to Group VIII of the transition elements of the
peri-odic table and resembles iron and nickel in many
chemical and physical properties It has one naturally
occurring isotope, with an atomic weight of 58.194
Cobalt as a metal is lustrous and silvery with a bluish
tinge It has an allotropic form that is stable only
above 417° Celsius Its density is 8.90 grams per cubic
centimeter; it has a melting point of 1,495° Celsius
and a boiling point of 3,100° Celsius Cobalt is known
to exist in more than two hundred ores These are
in-variably associated with nickel and often also with
cop-per and lead Cobalt is tougher, stronger, and harder than nickel and iron although less hard than iridium and rhodium It is ferromagnetic at less than 1,000° Celsius Like other transition elements, it has multiple oxidation states (II and III are most common), forms coordination complexes, and produces several color-ful compounds and solutions
Description, Distribution, and Forms Cobalt is about 29 parts per million of the Earth’s crust, making it the thirtieth element in order of abundance It is less abundant than the other first-row transition elements except scandium Other than the reserves of cobalt in Africa and Canada, there are smaller reserves in Australia and in Russia In 2006, for example, the leading producers of cobalt ore were the Democratic Republic of the Congo (41 percent), Zambia (12 percent), Australia (11 percent), Canada (10 percent), Russia (8 percent), Cuba (6 percent), and China (3 percent) Total world production was about 67,500 metric tons
Studies have shown that land with a cobalt defi-ciency will cause ruminant animals to lose their appe-tite, lose weight, and finally die; the disease is essen-tially a vitamin B12deficiency Vitamin B12is necessary
in ruminants for metabolism In other animals cobalt does not seem to be essential However, humans do need vitamin B12, also called cyanocobalamine; in hu-mans a B12deficiency causes megaloblastic anemia Cobalt appears in many materials, including soils and water There is evidence that minute quantities can be harmful to higher plant life It can also be harmful to animals; for example, sheep are harmed if they consume more than 160 milligrams of cobalt per
45 kilograms of weight There is no evidence that the normal human level of exposure to cobalt is harmful
History Egyptian pottery from 2600 b.c.e., Iranian glass from
2250 b.c.e., and Egyptian and Babylonian blue glass from 1400 b.c.e owe their blue color to cobalt Appar-ently, however, the art of making blue glass from co-balt ores disappeared until the end of the fifteenth century, when Christoph Schiirer used cobalt ores to impart a deep blue color to glass Cobalt ores were used not only to color glass but also as a blue paint for glass vessels and on canvas In 1735, Swedish chem-ist Georg Brandt recognized the source of the color and is considered the discoverer of cobalt In 1780, Torbern Olaf Bergman showed it to be a new element
Trang 2Although the name is close to the Greek cobalos, for
mine, the word cobalt is thought to come from the
German word Kobald, for goblin or evil spirit Miners
called certain ores kobald because they did not
pro-duce copper but did propro-duce arsenic compounds that
were harmful to those near the smelting process
Obtaining Cobalt
Cobalt is usually produced as a by-product of copper,
nickel, or lead, and the extraction method depends
on the main product In general, the ore is roasted to
remove gangue material as slag and produce a
mix-ture of metals and oxides The copper is removed with
sulfuric acid The iron is precipitated with lime, and
sodium hypochlorite precipitates the cobalt as a
hy-droxide, which is reduced to metal by heating with
charcoal
Uses of Cobalt
In the United States, superalloys account for 45
per-cent of cobalt use Other uses include magnetic alloys,
cemented carbides, catalysts, driers in paint,
pig-ments, steel, welding materials, and other alloys One
isotope, cobalt 60, is important as a source of gamma
rays It is used in the medical field to treat
ma-lignant growths The steel alnico, which also
contains aluminum and nickel, is used to make
permanent magnets that are twenty-five times
as strong as ordinary steel magnets In the
ce-ramics industry, cobalt is used as a pigment to
produce a better white by counterbalancing
the yellow tint caused by iron impurities
C Alton Hassell
Further Reading
Greenwood, N N., and A Earnshaw “Cobalt,
Rhodium, and Iridium.” In Chemistry of the
Elements 2d ed Boston:
Butterworth-Heine-mann, 1997
Hampel, Clifford A., ed The Encyclopedia of the
Chemical Elements New York: Reinhold, 1968.
Kim, James H., Herman J Gibb, and Paul D
Howe Cobalt and Inorganic Cobalt Compounds.
Geneva, Switzerland: World Health
Organi-zation, 2006
Leopold, Ellen “The Rise of Radioactive
Co-balt.” In Under the Radar: Cancer and the Cold
War New Brunswick, N.J.: Rutgers
Univer-sity Press, 2009
Mertz, Walter, ed Trace Elements in Human and
Animal Nutrition 5th ed 2 vols Orlando, Fla.:
Aca-demic Press, 1986-1987
Ochiai, Ei-ichiro General Principles of Biochemistry of the Elements Vol 7 in Biochemistry of the Elements New
York: Plenum Press, 1987
Silva, J J R Fraústo da, and R J P Williams “Nickel
and Cobalt: Remnants of Life?” In The Biological Chemistry of the Elements: The Inorganic Chemistry of Life 2d ed New York: Oxford University Press, 2001 Syracuse Research Corporation Toxicological Profile for Cobalt Atlanta, Ga.: U.S Dept of Health and
Hu-man Services, Public Health Service, Agency for Toxic Substances and Disease Registry, 2004
Weeks, Mary Elvira Discovery of the Elements 7th ed.
New material added by Henry M Leicester Easton, Pa.: Journal of Chemical Education, 1968
Web Sites Natural Resources Canada Canadian Minerals Yearbook, Mineral and Metal Commodity Reviews
http://www.nrcan-rncan.gc.ca/mms-smm/busi-indu/cmy-amc/com-eng.htm
Summaries, 2009
Data from the U.S Geological Survey,
U.S Government Printing Office, 2009.
Superalloys 46%
Cemented carbides 8%
Metallic applications 15%
Chemical applications 31%
U.S End Uses of Cobalt
Trang 3U.S Geological Survey
Cobalt: Statistics and Information
http://minerals.usgs.gov/minerals/pubs/
commodity/cobalt
See also: Alloys; Canada; Ceramics; Congo,
Demo-cratic Republic of the; Magnetic materials; Metals and
metallurgy; Russia; Steel
Cogeneration
Category: Energy resources
Cogeneration is the productive use of waste heat from
industrial processes or from electrical power
genera-tion Heat from cogeneration may be used to produce
electricity or in manufacturing.
Definition
Cogeneration refers to methods of producing
electri-cal power from heat that would otherwise be wasted
as well as to other ways of using waste heat
produc-tively Cogeneration results in energy savings and,
particularly when it can be made economically
feasi-ble enough to be applied widely, in the conservation
of nonrenewable energy resources A considerable
amount of heat—and therefore energy—is wasted
in the production of electrical power and in many
manufacturing operations
Overview
The generation of electricity from fossil fuels involves
the use of heat to transform the chemical energy
stored in the fuels into high-pressure,
high-tempera-ture steam The steam drives turbogenerators, which
in turn produce electricity A waste product from this
operation is low-temperature steam, which must be
cooled by large amounts of water before it can be
recy-cled back in liquid form to the plant’s boiler One goal
of cogeneration is harnessing this low-pressure steam
Water must undergo a phase change—that is, it
must be heated enough to be turned from liquid to
steam—in order to produce electricity Producing
steam is an energy-intensive process because of the
physical nature of water Once water in its liquid phase
reaches a temperature of 100° Celsius, its
tempera-ture stabilizes and remains the same for the amount of
time it takes to turn the water to steam The heat
re-quired for this phase change is called latent heat La-tent heat cannot be measured in the same way that sensible heat (heat that raises the temperature of a material) can be Utilities have generally been unable
to use this latent heat, and capturing this energy is a major point of cogeneration
Cogeneration can be achieved in two different cy-cles, the topping cycle and the bottoming cycle Power utilities use only the topping cycle, which uses energy input to generate electricity and uses the waste heat for a practical purpose A number of other industries use this cycle as well The bottoming cycle, which ap-plies the energy input to process heat and uses the waste to produce electricity, is not as common One example of its use is in the paper industry Waste heat from the kraft chemical recovery process is captured
in a series of water-filled tubes, and the resultant steam is used to generate electricity and process heat Efficiencies can reach 85 percent at integrated pulp and paper mills, since exhaust steam from the power-house can help dry the paper A modern mill can pro-duce 75 percent or more of the electrical power and steam that it needs There have been cases where pa-per mills have been able to supply electricity to local areas that have lost power because of natural disasters The implementation of cogeneration depends on its economic feasibility Some proposed projects are not put into operation because of the significant capi-tal expenditures involved Perhaps the most sensible approach involves cooperative agreements between users and producers of electricity Substantial energy savings are possible The European Union garners more than 10 percent of its total energy from cogeneration
Vincent M D Lopez
See also: Electrical power; Energy economics; Steam and steam turbines
Commoner, Barry
Category: People Born: May 28, 1917; Brooklyn, New York
Commoner, a research biologist, has been referred to as
“Dr Ecology,” “the Paul Revere of ecology,” and an “el-der of America’s environmental movement.”
Trang 4Biographical Background
Barry Commoner grew up on the streets of Brooklyn
with an unusual interest in and zeal for the outdoors
Fascinated by nature, he spent weekends exploring
parks for specimens to study under the microscope
His interest in biology was spurred at James Madison
High School and Columbia University Following
com-pletion of his bachelor’s degree he entered Harvard
University and earned a doctoral degree in cellular
physiology He remained an academic scholar with the
exception of a stint in the Navy during World War II
and a year as associate editor of Science Illustrated in
1946 His teaching career started at Queens College,
and he later returned there following thirty-four years
at Washington University He left Washington
Univer-sity to enter politics as the presidential candidate of
the Citizens Party in 1980 He headed the Center for
the Biology of Natural Systems at Queens College
un-til leaving the post in 2000 Into his tenth decade, he
remained a revered voice in the field of ecology
Impact on Resource Use
As a research scientist, Commoner contributed
con-siderably to knowledge of viral function and to
cellu-lar research with implications for cancer diagnosis As
an environmental activist, he was vital in educating
the public that in the Earth environment “everything
is connected to everything else.” A prolific author,
Commoner wrote numerous books about the
envi-ronment, including Science and Survival (1966), Making
Peace with the Planet (1992), and Zeroing out Dioxin in the
Great Lakes: Within Our Reach (1996).
As an “eco-socialist,” Commoner rejected the
envi-ronmental degradation caused by capitalism and
ad-vocated ecological priorities over economic ones in
a system of communal ownership To this end,
Com-moner has emphasized nature over technology,
hold-ing that the interconnectedness of nature and
human-kind makes it impossible to escape the consequences
of our treatment of the planet In the second of his
“Four Laws of Ecology,” Commoner states that
“Every-thing must go somewhere There is no ‘waste’ in
nature and there is no ‘away’ to which things can
be thrown.” Hence, resources must be used both
sustainably and with full responsibility for the impact
of their use on the system as a whole
Kenneth H Brown
See also: Biosphere; Conservation; Ecosystems;
En-ergy politics; Environmental degradation, resource
exploitation and; Environmental ethics; Environmen-tal movement; Renewable and nonrenewable re-sources; Sustainable development
Composting
Categories: Environment, conservation, and resource management; plant and animal resources
Composting is a way for gardeners and farmers to en-rich and otherwise improve the soil while reducing the flow of household waste to landfills Essentially the slow natural decay of dead plants and animals, com-posting is a natural form of recycling in which living organisms decompose organic matter.
Background The decay of dead plants and animals starts when mi-croorganisms in the soil feed on dead matter, break-ing it down into smaller compounds usable by plants Collectively, the breakdown product is called humus,
a dark brown, spongy, crumbly substance Adding hu-mus to soil increases its fertility Compost may be
fined in various ways The Oxford English Dictionary
de-fines it (as a noun) as a mixture of ingredients for fertilizing or enriching land, a prepared manure or
mold; Webster’s New World Dictionary defines it (as a
verb) as the making of compost and the treatment of soil with it Compost and composting derive from the
Old French composter, “to manure” or “to dung.”
History The origins of human composting activities are bur-ied in prehistory Early farmers undoubtedly discov-ered the benefits of compost, probably from animal manure deposited on or mixed with soil In North America, American Indians and then Europeans used compost in their gardens Public accounts of the use
of stable manure in composting date back to the eigh-teenth century Many New England farmers also found it economical to use fish in their compost heaps
While living in India from 1905 to 1934, British agronomist Sir Albert Howard developed today’s home composting methods Howard found that the best compost pile consists of three parts plant matter
to one part manure He devised the Indore method of
Trang 5composting, alternating layers of plant debris,
ma-nure, and soil to create a pile Later, during the
com-posting process, he turned the pile or mixed in
earth-worms
How Composting Works
Composting is a natural form of recycling that takes
from six months to two years to complete Bacteria are
the most efficient decomposers of organic matter
Fungi and protozoans later join the process, followed
by centipedes, millipedes, beetles, and earthworms
By manipulating the composition and environment
of a compost pile, gardeners and farmers can reduce
composting time to three to four months Important
factors to consider are the makeup of the pile, the
sur-face area, the volume, the moisture, the aeration, and the temperature of the compost pile
Yard waste such as fallen leaves, grass clippings, some weeds, and the remains of garden plants make excellent compost Other good additions to a home compost pile include sawdust, wood ash, and kitchen scraps, including vegetable peelings, egg shells, and coffee grounds Microorganisms digest organic matter faster when they have more surface area to work on Gardeners can speed the composting process by chop-ping kitchen or garden waste with a shovel or running
it through a shredding machine or lawn mower The volume of the compost pile is important be-cause a large compost pile insulates itself, holding in the heat of microbial activity A properly made heap will reach temperatures of about 60° Celsius in four or five days Then the pile will settle, a sign that is work-ing properly Piles 0.76 cubic meter or smaller cannot hold enough heat, while piles 3.5 cubic meters or larger do not allow enough air to reach the microbes
in the center of the pile These portions are important only if the goal is fast composting Slower composting requires no exact proportions
Moisture and air are essential for life Microbes function best when the compost heap has many air passages and is about as moist as a wrung-out sponge Microorganisms living in the compost pile use the car-bon and nitrogen contained in dead matter for food and energy While breaking down the carbon and ni-trogen molecules in dead plants and animals, they also release nutrients that higher organisms such as plants can use
The ratio of carbon to nitrogen found in kitchen and garden waste varies from 15 to 1 in food waste to
700 to 1 in wood A carbon-to-nitrogen ratio of 30 to 1
is optimum for microbial decomposers This balance can be achieved by mixing two parts grass clippings (carbon-to-nitrogen ratio, 19:1) and one part fallen leaves (carbon-to-nitrogen ratio, 60:1) This combina-tion is the backbone of most home composting sys-tems
Modern Uses and Practice Composting remains an important practice Yard and kitchen wastes use valuable space in our landfills These materials compose about 20 to 30 percent of all household waste in the United States Composting household waste reduces the volume of municipal solid waste and provides a nutrient-rich soil additive Compost or organic matter added to soil improves
A woman mixes her indoor composting box that contains worms
that convert household waste into compost (Beth Balbierz/MCT/
Landov)
Trang 6soil structure, texture, aeration, and water retention.
It improves plant growth by loosening heavy clay soils,
allowing better root penetration It improves the
water-holding and nutrient-holding capacity of sandy
soils and increases the essential nutrients of all soils
Mixing compost with soil also contributes to erosion
control and proper soil pH balance
Some cities collect and compost leaves and other
garden waste and then make it available to city
resi-dents for little or no charge Some cities also compost
sewage sludge or human waste, which is high in
nitro-gen and makes a rich fertilizer Properly composted
sewage sludge that reaches an internal temperature
of 60° Celsius contains no dangerous disease-causing
organisms One possible hazard, however, is that it
may contain high levels of toxic heavy metals,
includ-ing zinc, copper, nickel, and cadmium
The basic principles of composting used by home
gardeners also are used by municipalities composting
sewage sludge and garbage, by farmers composting
animal and plant waste, and by some industries
com-posting organic waste Food and fiber industries, for
example, compost waste products from canning,
meat processing, dairy, and paper processing
Judith J Bradshaw-Rouse
Further Reading
Bem, Robyn Everyone’s Guide to Home Composting New
York: Van Nostrand Reinhold, 1978
Campbell, Stu Let It Rot! The Gardener’s Guide to
Com-posting 3d ed Pownal, Vt.: Storey
Communica-tions, 1998
Jenkins, Joseph C The Humanure Handbook: A Guide to
Composting Human Manure 3d ed White River
Junction, Vt.: Chelsea Green, 2005
Martin, Deborah L., and Grace Gershuny, eds The
Rodale Book of Composting New, rev ed Emmaus,
Pa.: Rodale Press, 1992
Simons, Margaret Resurrection in a Bucket: The Rich
and Fertile Story of Compost Crows Nest, N.S.W.:
Al-len & Unwin, 2004
Web Sites
Cornell Waste Management Institute,
Department of Crop and Soil Sciences,
Cornell University
Cornell Composting
http://www.css.cornell.edu/compost/
Composting_Homepage.html
U.S Environmental Protection Agency Composting
http://www.epa.gov/wastes/conserve/rrr/
composting/index.htm See also: Conservation; Erosion and erosion control; Incineration of wastes; Landfills; Recycling; Soil deg-radation; Soil management; Waste management and sewage disposal
Comprehensive Environmental Response, Compensation, and
Liability Act See Superfund
legislation and cleanup activities
Concrete See Cement and concrete
Congo, Democratic Republic of the
Categories: Countries; government and resources
Beginning in the late nineteenth century, the Congo (now Democratic Republic of the Congo), then a Bel-gian colony, was recognized as a potentially rich source for raw materials By the time of Congolese indepen-dence in 1960, certain provincial regions, particu-larly the former colonial province of Katanga, had become the center for the mining and transport, by for-eign companies, of a number of major mineral re-sources, including copper, cobalt, zinc, cadmium, ger-manium, tin, manganese, and coal.
The Country The Democratic Republic of the Congo (DRC) is located in west-central Africa, with its westernmost limit running along the Atlantic coast The country
is separated from the Republic of the Congo by the Congo River Its other neighbors are the Central Af-rican Republic, Sudan, Uganda, Rwanda, Burundi, Tanzania, Zambia, and Angola Although not all areas
of the country receive the massive amounts of rain-fall characteristic of the interior Congo basin zone, there is an extensive zone that is heavily forested
Trang 7236 • Congo, Democratic Republic of the Global Resources
Democratic Republic of the Congo: Resources at a Glance
Official name: Democratic Republic of the Congo Government: Republic
Capital city: Kinshasa Area: 905,420 mi2; 2,344,858 km2
Population (2009 est.): 68,692,542 Language: French
Monetary unit: Congolese franc (CDF)
Economic summary:
GDP composition by sector (2000 est.): agriculture, 55%; industry, 11%; services, 34%
Natural resources: cobalt, copper, niobium, tantalum, petroleum, industrial and gem diamonds, gold, silver, zinc,
manganese, tin, uranium, coal, hydropower, timber
Land use (2005): arable land, 2.86%; permanent crops, 0.47%; other, 96.67%
Industries: mining (diamonds, gold, copper, cobalt, coltan, zinc), mineral processing, consumer products
(including textiles, footwear, cigarettes, processed foods and beverages), cement, commercial ship repair
Agricultural products: coffee, sugar, palm oil, rubber, tea, quinine, cassava (tapioca), palm oil, bananas, root crops,
corn, fruit, wood products
Exports (2007): $6.1 billion
Commodities exported: diamonds, gold, copper, cobalt, wood products, crude oil, coffee
Imports (2007) $5.2 billion
Commodities imported: foodstuffs, mining and other machinery, transport equipment, fuels
Labor force (2007 est.): 23.53 million
Labor force by occupation (1991 est.): agriculture, 65%; industry, 16%; services, 19%
Energy resources:
Electricity production (2006 est.): 7.243 billion kWh
Electricity consumption (2006 est.): 5.158 billion kWh
Electricity exports (2006 est.): 1.799 billion kWh
Electricity imports (2006 est.): 6 million kWh
Natural gas production (2007 est.): 0 m3
Natural gas consumption (2007 est.): 0 m3
Natural gas exports and imports (2007 est.): 0 m3
Natural gas proved reserves ( Jan 2008 est.): 991.1 million m3
Oil production (2007 est.): 22,160 bbl/day Oil imports (2006 est.): 8,220 bbl/day Oil proved reserves ( Jan 2008 est.): 180 million bbl Source: Data from The World Factbook 2009 Washington, D.C.: Central Intelligence Agency, 2009.
Notes: Data are the most recent tracked by the CIA Values are given in U.S dollars Abbreviations: bbl/day = barrels per day;
GDP = gross domestic product; km 2 = square kilometers; kWh = kilowatt-hours; m 3 = cubic meters; mi 2 = square miles.
Current labor force occupational data are unavailable.
Kinshasa
Kenya Sudan
Tanzania
Angola
Zambia
Gabon
Central African Republic
Uganda
Malawi
Burundi Rwanda Cameroon
Republic
of the
Congo
Congo
Democratic Republic of the
A t l a n t i c
O c e a n
Trang 8Traditionally the world-famous Congo River served
as the main artery of access to the interior
Develop-ment of modern alternative modes of transport,
espe-cially railways, has been gradual and not altogether
successful
The potential global impact of DRC mineral
pro-duction has been reduced by the country’s chronic
political instability, much of which has been
concen-trated in mineral-rich areas of the country Another
problem affecting the global status of exports from
the Democratic Republic of the Congo is the
predom-inance of foreign investors (in the form of
multina-tional concessionaires) in the mining sector This
seems to be less a problem of antiforeign sentiment
than a result of “shifting” foreign involvement Many
foreign operations have been hampered by unstable
conditions, while others have actually withdrawn
en-tirely from development commitments signed with
the government in Kinshasa, the country’s capital
Copper
The large southern area of the Democratic Republic
of the Congo, formerly the Shaba (1971-1997) or
Katanga (1960-1971, 1997-2009) Province but in 2009
divided into four provinces—Haut-Katanga,
Tangan-yika, Lualaba, and Haut-Lomami—is part of an
enor-mous metallogenic zone running from Angola in
West Africa to Zambia The area is commonly called
the “Copperbelt” of Africa, although other minerals,
especially cobalt, are mined in the same area It is
esti-mated that 10 percent of the world’s copper reserves
(approximately 50 million metric tons) are located
within the Democratic Republic of the Congo Before
the year 2000, the country’s copper was mined
pri-marily by the state-run firm Gécamines (Générale des
Carrières et des Mines) About a decade after the
country gained independence, Gécamines received
world attention for the relatively low cost of its copper,
but this advantage was lost in stages as various
disrup-tive factors reversed the situation, making Congolese
copper much more expensive on the world market
Copper production by Gécamines was still
rela-tively high at the beginning of the twenty-first century
(about 19,000 metric tons) but fell by about 1,000
metric tons, largely because of an inability to operate
many existing mines at full capacity; some mines were
completely inactive A marked example of declining
productivity was the Society for Congolese Industrial
and Mining Development (Sodimco), a minor
“coun-terpart” to Gécamines, whose output in 2001 was less
than 550 metric tons of copper Sodimco extracted the copper from the Musoshi and Kinsenda mines, whose copper reserves have been estimated to be more than 220 million metric tons
In an effort to obtain a more competitive global po-sition for DRC copper, the Kinshasha government concluded a partnership between Gécamines and the Finnish-run Outokumpu Mining Group to exploit both copper and cobalt reserves The trend of seeking collaborative operations with foreign mining firms in-creased over the next few years In 2002, Anvil Mining,
an Australian firm with operations in Canada, ob-tained a concession for operating the Dikulushi cop-per and silver mine in the traditional Katanga mining zone Results were encouraging: Mining yielded al-most 13,000 metric tons of copper in 2003, which was followed by announcement of plans to expand the Dikulushi mine
Another foreign concern, International Panorama Resources (IPR) of Canada, joined (at 51 percent par-ticipation) with Gécamines to use high-tech methods
to reprocess copper- and cobalt-bearing tailings from mines located at Kambove and Kakanda The initial level of IPR’s involvement, like that of other foreign companies concerned about declining public secu-rity in the areas of their concessions, was cut back despite signs that copper prices were returning to rea-sonably attractive levels
In fact, the 1999 price of $0.27 per kilogram of cop-per recovered to $1.70 by 2006 However, in the pe-riod between 2006 and 2009, the price fluctuated con-siderably, and available stockpiles during the 2008 onset of the global financial and economic crisis sug-gested that decreasing demand would push prices down again, below $1.50 or even lower
Despite recurring technical, financial, and politi-cal difficulties in mining copper, the DRC continued
to receive bids from foreign firms interested in either mining or processing the country’s copper deposits
In 2004, for example, the South African mining com-pany Metorex agreed to mine and process ore (in-cluding cobalt) in the region near Lubumbashi (spe-cifically the Ruashi and Etoile mines)
Specialized information services on the Web (such
as MBendi Information) list specific ongoing mining projects and companies, both foreign and national, involved in the Congolese copper sector The total of
at least one dozen active firms and projects suggests that the DRC is dedicated to maintaining copper min-ing as a priority
Trang 9The DRC is one of ten sub-Saharan countries in Africa
with substantial reserves of cobalt (the DRC and
Zam-bia are the most important) The cobalt is frequently
found in veins bearing copper and, along with nickel,
is separated out as a by-product of copper mining
The DRC’s location across the central African
Copperbelt means that the country has a substantial
share, almost 35 percent, of the world’s cobalt In
modern times the metallic element colbalt (Co) is
used to make strong alloys and is essential as a
radio-isotope (Cobalt 60) in producing gamma rays
Specialized importers’ demand, therefore, is
rela-tively high Although government-run Gécamines
suf-fered cobalt production setbacks, because of
under-utilization of partially exploited mining locations, in
the years after 2000, the company continued to enter
into joint exploitation contracts with foreign firms
in-terested in particularly promising special projects
Perhaps the most outstanding of these projects was
the 2004 acquisition, by the London-based Adastra
Minerals, of full rights to process massive tailings
sites at the Kolwezi location This ambitious project
set as its aim reclaiming major amounts of both
cop-per (more than 40,000 metric tons annually) and
cobalt (more than 6,000 metric tons annually) from
more than 100 million metric tons of oxide tailings
at Kolwezi
Petroleum and Natural Gas
The limited (22-kilometer) stretch of the DRC’s
At-lantic coast (running between northern Angola and
the oil-rich enclave of Cabinda) was the scene of oil
exploration activities as early as the 1960’s, but
pro-duction was not significant until offshore wells in the
same region began production in 1976 The Mibale
offshore field, eventually estimated to hold almost 50
percent of the coastal basin’s reserves, was discovered
in 1973 by Chevron More than forty wells had been
drilled, most offshore, by the mid-1980’s, yielding five
working oil fields and one natural gas field
Exploration of inland areas, especially along the
eastern border of the DRC and in the central Congo
basin, produced less promising results Some hope
for exploitation of proven reserves in the region
bor-dering Uganda was registered, but not effectively
pur-sued Natural gas reserves in regions close to the
Rwanda border await efficient exploitation In the
case of natural gas, not only infrastructural problems,
such as the remoteness of the region and lack of
ef-fective transport, but also recurrent political instabil-ity and regional violence have continued to hamper follow-up to exploratory soundings
As for the DRC’s more promising offshore petro-leum sector, a series of arrangements and rearrange-ments of foreign oil companies’ involvement in con-sortium agreements with the Kinshasha government have been made The most important consortium ar-rangement involved participation at 50 percent hold-ings by Congo Gulf Oil (Chevron), 32 percent by Congo Petroleum Company (Teikoku Oil of Japan), and 18 percent by Union Oil of California
Gold Mining for gold in the area around Namoya (some
250 kilometers from Bukavu, on the edge of forested areas leading eastward to the Rwandan and Ugandan borders), first by alluvial methods in the 1930’s, and then by open-pit mining in the 1950’s, was interrupted during the early years of Congolese independence Although production was restored gradually, periodic outbreaks of civil violence in key ore-producing sub-zones (Namoya, Twangiza, Kamituga, and Lugushwa) have hampered efforts to effectively exploit gold mining in the northeastern provincial region Anti-government rebel forces occupied, abandoned, then reoccupied the key population centers during the entire first decade after 2000
These disruptive conditions have not prevented key foreign mining concerns from seeking contrac-tual agreements for concessions from the Kinshasha government
Diamonds Although the DRC, and specifically the Kasai-Oriental Province, is potentially the largest producer of dia-monds in Africa, it has fallen far short of fulfilling this potential Despite the existence of a formal com-mercial diamond concession, Minière de Bakwanga (MIBA)—a joint operation involving the Belgian company Sibeka and the government of the DRC— only about a third of the country’s diamonds are ex-ported by MIBA Knowing the origin and channels pursued by many “informal” dealers to commercialize the majority of diamonds mined in the DRC is nearly impossible A major cause for this comes, again, from extremely unsettled political conditions and recur-ring outbreaks of violence Conditions of disorder lend themselves to the possibility of illicit dealings in the diamond market Fear of involvement in criminal
Trang 10diamond dealings (known in West and central Africa
as the “blood diamond” trade) caused the major
South African diamond importer Kimberley Process
to blacklist the DRC in 2004 This stopped officially
recognized export processes but did not stop
“pri-vate” intermediaries from conducting smuggling
op-erations Some estimates of the Congolese
govern-ment’s losses because of diamond smuggling have
been as high as a one-half billion dollars annually
In the same year that Kimberley denounced
dia-mond operations in the DRC, De Beers arranged a
confidentiality-covered diamond concession
agree-ment, committing more than $200 million to conduct
much needed improvements
Manganese
The DRC produced upwards of 45,000 metric tons of
manganese ore annually in the early 1970’s, most of
which was transported by rail from the Lulua basin to
export facilities at Benguela on the Angolan coast
The principal, if not the only, firm involved in these
operations, the Kisenge Manganese Mining
Enter-prise, experienced dramatic declines in exports
(down to a little more than 27,000 metric tons in the
late 1980’s) during the long period of civil war in
An-gola In 1993, production came to a de facto end
Kisenge, in its efforts to regain a section of the
manga-nese market by introducing high-tech dry-cell modes
to process high-grade electrolytic manganese
diox-ide, has encountered difficulty, given the fact that
sev-eral of its African neighbors also produce manganese
at attractive prices
Tantalum and Niobium
The DRC possesses a number of coltan
(tantalum-ore) producing mines in the Lake Kivu region The
primary mining operation there is Anvil Mining (with
home offices in Australia and Canada), a firm which is
heavily involved in DRC copper mining Tantalum,
along with a similar metal always found alongside
tan-talum, is a highly corrosion-resistant element used
widely as a component in metal alloy processes
Al-though tantalum could be an increasingly significant
DRC export, two factors may limit such development
(beyond the fact that Australia produces most of the
tantalum for the world market): Almost all the central
African neighbors of the DRC—including Rwanda,
Tanzania, Uganda, Zambia, and Gabon—also
pro-duce tantalaum for export; and, after Anvil Mining
launched its major mining operations in the first few
years of the twenty-first century, controversy over the ecological impact such mining might have, both for surrounding forests and for animal life in the region, has come to the forefront
Other Resources Given the extensive forested area of the Congo River basin, the DRC is in a position to export a variety of rare hardwoods and some industrially attractive com-mon lumber This sector has yet to develop to its full potential because of the lucrative, if risky, mineral in-dustry
Byron D Cannon
Further Reading Nest, Michael Wallace, François Grignon, and Emizet
F Kisangani The Democratic Republic of Congo: Eco-nomic Dimensions of War and Peace Boulder, Colo.:
Lynne Reinner, 2006
Renner, Michael, and Thomas Prugh The Anatomy of Resource Wars Washington, D.C.: Worldwatch
Insti-tute, 2002
Renton, Dave, David Seddon, and Leo Zellig The Congo: Plunder and Resistance New York: Zed Books,
2007
Wolfire, Deanna, Jake Brunner, and Nigel Sizer For-ests and the Democratic Republic of Congo: Opportunity
in a Time of Crisis Washington, D.C.: World
Re-sources Institute, 1998
See also: Belgium; Cobalt; Copper; Diamond; Gold; Oil and natural gas distribution
Conservation
Category: Environment, conservation, and resource management
Humanity’s footprint is being felt around the world.
As the global population continues to increase, the nat-ural resources necessary to sustain life continue to decline Fresh water, fossil fuels, and arable land are just a few of the natural resources that must be properly managed to sustain a global population that may reach 9.1 billion by the year 2050, as predicted by the United Nations.