Kilembe minerals: The vitamins of energy transition

Author: Eng Jonard Asiimwe. PHOTO/FILE/COURTESY

What you need to know:

  • Uganda should not wait to capitalize on the world's growing appetite for critical minerals as the globe gears up for a major energy transition that aims at zero emissions by 2050. 

Kilembe copper was partly mined and its potential boosted Uganda’s economy between the 1960’s and 1970’s. However, due to relative economic stagnation under the unpredictable leadership of President Idi Amin, the mine ceased its operation in 1982 amidst disturbing copper prices. Kilembe Mines have been dormant for nearly four decades.

In reference to the past, copper mineralization in the Rwenzori sub-region rocks was first reported in 1906 by Rocatti, and exploration started in the 1920’s.

According to a JICA report (1978), copper has been found at several localities in Uganda but the only major deposit discovered to date is Kilembe, in Western Uganda’s Kasese District, where there’s copper-cobalt sulphide mineralization. The primary ore consists of mainly chalcopyrite, pyrite, and pyrrhotite with minor linnaeite. Apart from cobalt, the ore is also associated with nickel, gold, and some kaolin. Other areas where copper mineralisation has been noted are Bobong, Lokapeliethe and Loyolo in the Karamoja sub-region as well as Kampono and Kitaka in Mbarara and Buhweju districts respectively.

The Kilembe Schist series is divided into three groups that include: the Upper (UK), the Middle (MK), and the Lower (LK).

Kilembe has an estimated 5,000,000 tons of copper deposits along with other undetermined or unexplored copper ore, spread across approximately 2,800 acres (1,100 ha).

It’s believed that, between 1957 and 1979, an ore of copper that was mined and processed or treated accounted for about 217,000 tons of blister copper that was exported.

In 1965, Botswana was the leading copper producer in Africa, followed by the DRC. Uganda was fifth, just below South Africa. Today, the Democratic Republic of Congo (DR Congo) tops the list with around 1.88 million metric tons of copper produced in 2021, while Uganda is nowhere but a beginner.

Kilembe: Once an ace in Uganda’ s hands

Kilembe had its own race. Whatever happened and how it has impacted the country is a topic for another day. For instance, Kilembe’s enumeration was 1,874 workers by 1955 and 5,377 workers (348 working at the smelter in Jinja and 5,028 working at Kilembe) by the end of 1965. Almost half of the current labor force is reportedly employed directly in the oil and gas industry (by PAU). In 1957, Kilembe committed about USD $348,754 (about Shs1.3billion to 2621 workers) and in 1964, Kilembe’s wage bill was almost tripled to $943,000 (about Shs3.5billion being paid to 4380 workers (average pay of about Shs800,000). This wage bill mostly went to the Ugandan Bakiga tribal group, who by 1965 comprised at least 38.4% of the total workforce- arguably forming the the biggest workforce at the mine in the 1950s, followed by the Batooro.

It’s historical to note that Kilembe Mine attracted the first hydro power station in the west, the 5MW Mubuku 1 power station that was commissioned in the 1950's, even before the said oldest Naluubale dam, which was commissioned in 1954. Kilembe, once an ace in the pearl of Africa can now pick up from where it stopped since her closure undeniably sucked life out of the then-forming formal mining sector inin the East African nation. Trained miners who went jobless seem to have played a key role in the swelling of Uganda’s informal artisanal and small-scale mining sector.

Why Kilembe cannot wait

Uganda itself should not wait to capitalize on the world's growing appetite for critical minerals. This partly explains why there is a beehive of activity in the Busoga sub-region, championed by the Makutu Rare Earths Exploration projects.

As the world prepares for an energy transition in order to meet the Paris Agreement's goal of zero net emissions by 2050, copper, cobalt, and other critical minerals are at the forefront of the transition due to their electrical and thermal conductivity. Critical minerals have other unique features such as physical, chemical, magnetic, and luminescent properties. Critical minerals have proven high performance at reduced energy consumption, greater efficiency, miniaturization, speed, durability, and extra.

Solar power systems contain approximately 5.5 tons of copper per MW.

It is projected that 262 GW of new solar installations between 2018 and 2027 in North America alone will require 950,000 tons of copper. All sources of renewable energy, electric vehicles, and the tech industry require huge amounts of copper too.

Green Revolution investments in 2020 totaled $303.5B, more than 19.8% of power generated in 2020 and a projected 35% rise in power generation is forecasted by 2030.

There are more than 70 million kms of transmission and distribution lines worldwide, and 150 Mt of copper and 210 Mt of aluminum are locked in grids. Power networks are said to attract an investment of about $620 billion by 2040.

According to the International Copper Association, fossil-free energy generation technologies coupled with battery storage generate a potential of over 75,000 tonnes of additional annual copper demand in only the U.S.

The United States Department of Defense is said to use up to 750,000 tons of minerals annually in the manufacture of military gear, weapon systems, and other defense applications. For instance, copper makes high quality military vehicles such as aircraft, and its ability to resist corrosion has advanced it into naval vessels and Coast Guard ships.

The Chilean Consejo Minero (Chilean Mining Council), the world's top copper producer (Chile), estimates that by 2023, 63 percent of electricity will come from clean energy sources. Copper’s chemical composition makes it the most cost-effective material for application in almost all sustainable energy systems, including cables, networking, batteries, transistors, inverters, and almost every electronic device has copper occurrences.

As the world prepares for an energy transition, copper, as a key component in emerging clean energy technologies, will see an increase in demand. For instance, a tonne of copper currently goes for between $7,000 and $11,001- not forgetting that copper prices reached an all-time high of $10,512 per metric ton on May 9, marking a 130% growth since March 22, 2020.

This resonates with the May 2021 CNBC opinion by the founder and managing director of U.S. Hedge Fund Livermore Partners, David Neuhauser, that: "I think copper is the new oil, and I think copper, for the next five to 10 years, is going to look tremendous with the potential for $20,000 per metric ton."

Kilembe revival: What should be done?

Kilembe’s mineral wealth potential is huge. NDPIII has prioritized the exploitation of mineral resources, including critical minerals and other potential minerals.

Uganda, East Africa, and Africa are urgently in need of copper for domestic consumption in manufacturing finished products for cables, transformers, inverters, as well as military equipment.

Uganda has pioneered the electric vehicle manufacturing industry. EVMs depend on copper, electricity, utility batteries, phones, and computers. The East African community is a sleeping market that needs no transit as well as the international market.

Everyone is watching the green energy revolution. Uganda, or any other country, would wish to take advantage of the copper demand. I believe that we do not need Project Fragmentation which will automatically call for longer project execution time. However, as a country that needs to position itself in the copper and cobalt markets, we need a developer with a Simultaneous Implementation Approach in all aspects of the project, and the proposed Project Execution Time(from establishment of the mine to processing) should be as short as possible. From power station generation capacity upgrade to mine rehabilitation, from more exploration to establishment of plants that are capable of processing at least 99.8 % pure metals (cathodes), from production of finished copper wires, transformers, and transmitters to water approaches and community environment and empowerment strategies, and extra.

West Bukangama (upper) deposit: More acreage must be explored

According to the JICA report of 1978, a team of ten Japanese who included metallurgists, geologists, and electrical engineers led by Roach Hirata conducted a technical survey with help from Kilembe Mines Ltd general manager at the time, Captain S. Gala.

The team from Japan had some findings. The Upper Bukangama deposit was re-estimated and, in their findings, a substantially larger ore reserve of more than 1,243,240 tons, in comparison to the earlier estimates of 475,800 tons by the geological department of Kilembe Mine, was found to exist.

It’s recommendable to apply different drilling and exploration approaches. There is a need for re-exploration of the west Bukangama prospect and other areas of potential in close proximity to the mine. By increasing the ore reserve, it will benefit both the company and shareholders, as the government plans to introduce a minerals production sharing agreement (MPSA) in Kilembe, plus earn through royalties. According to the report and based on reason and common sense, even a blind ore body or a medium-sized ore deposit may be exploited given its close proximity to the chief mine.

In the 1950s and 60’s, Falconbridge is said to have extensively explored the surface for ore deposits. According to the JICA report, the underground exploration may prove additional ore reserves within the proximity of the proven ore deposits.

Rivers Nywamwamba and Mubuku: Water stress Vs hydro power generation and copper processing

Mubuku hydro power stationis fed by melting glaciers from the Rwenzori Mountains that flow to Lake George. The Kasese Rivers are said to originate from the mountain.

Essentially, any developer of the new Kilembe should have intentions that go beyond the upgrading of the 1950-commissioned 5MW Mubuku I Power Station to a considerable MW of power but propose and immediately start the implementation of approaches to reduce stress on the existing water because it will in turn affect water flow that should generate power or process copper.

Numerous socio-economic activities such as subsistence agriculture, mining, and mini hydro-power generation have been taking place in the catchment areas of these rivers: Mubuku, Nyamwamba, Bujuku, Kyoho, Kanywankoko, Kithakena, and Ruboni, and this has inversely affected the watersheds, hence impacting river behaviour and water flow.

From a reasonable and realistic point of view, a developer of New Kilembe should:

  • Think of a solution to River Nyamwamba's behavior to avoid future infrastructure loss.
  • Identify areas in the watersheds like Sebwe and other tributaries of the River Mubuku that include Bujuku, Kyoho, Kanywankoko, Kithakena, and Ruboni.
  • Consider promoting the conservation of the ecological systems of the Rwenzori Mountains National Park.
  • Plan for organizing agricultural communities to improve land use practices such as tree harvesting, steep slope cultivation, and river bank cultivation
  • Propose, where possible, the Payments for Ecosystem Services (PES) to be implemented but affecting all partners.
  • Forest loss due to agriculture is estimated at 70 ha per year, with the prevailing years experiencing higher loss values than the previous years. A developer should propose landscape vegetation restoration programs such as tree planting on bare areas as well as river banks to improve vegetation cover and protect river banks from erosion.
  • Propose promoting efficient cooking energy or saving technologies like Liquefied Petroleum Gas, improved stoves, briquettes, and biogas so as to reduce the number of trees cut for wood fuel and charcoal burning. (Excerpts from a WWF report) 

Should a developer think of desalination at Kilembe?

It’s a fact that almost half of global copper or lithium production is concentrated in areas of high water stress, and Kasese is also a drier region in Uganda.

According to a report by the U.S. Geological Survey, a little more than 100,000 gallons of water per ton of copper is used in the production of copper from its ores. About 70,000 gallons per ton may be used in mining and concentrating the ore, and about 30,000 gallons per ton may be used to reduce the concentrate to refined copper.

Chile produces nearly a quarter of the world’s copper supply. The Northern provinces produce the majority of production. This region is one of the most water-stressed on the planet.

According to MineSpans' analysis, run-of-mine water volumes from copper mining in Chile are expected to increase by over 36 percent in the next decade.

Desalination and the use of seawater are expected to grow at a rate of 230 percent over the next decade, according to the Chilean Copper Commission (Comisión Chilena del Cobre (COCHILCO).

Does Kilembe need desalination?

Uganda’s land area covered by surface water bodies and wetlands is about 16% (37,166 km2). The Rwenzori region is estimated to cover an area of 7500 km2 (approximately 3.1% of the country). The region accesses the Kazinga channel, Lakes George and Edward to the south, protected areas to the east, and Lake Albert to the north. This presents an opportunity to think about desalination in the near future.

It’s interesting to note that today, several countries, including Chile, Bahamas, Maldives, Malta, and others, meet their water needs through desalination (the converting of seawater to freshwater for use).

In the world, there will never be a shortage of seawater, but the human race is heading for water shortages. Oceans make up 70% of the planet. The United Nations Environment Programme (UNEP) has noted that almost 16,000 desalination plants are operating in 177 countries.

Saudi Arabia’s 34 million population gets about 50 per cent of its drinking water from desalination. It’s an emerging industry but with its shortcomings, a developer of New Kilembe, according to my personal understanding, should propose an innovative approach towards desalination because, according to UNEP, 80 per cent of wastewater (whether it is the toxic brine generated by desalination or other types of waste) ends up in seas, rivers, lakes, and wetlands.

Innovation on recovering cobalt from pyrite (tailings)

Electromobility is a hit in town. Its demand for raw materials such as cobalt, graphite, and lithium has even forced the Chilean mining industry, which historically focused on copper only, to revert to recovering cobalt from tailings gotten in copper processing. Cobalt is present as a solid-solution within the crystalline structure of pyrite.

According to the JICA report, it is worthwhile to conduct metallurgical research to recover cobalt from pyrite concentrate, which could significantly contribute to profitability if successful.

A suitable developer of the Kilembe should have a detailed approach to recovering as much cobalt as possible from pyrite to a tune of at least 30% to 50% of which was previously disposed of as tailings.

Lastly, on a sad note, a developer of New Kilembe should expect dilapidated machines, no compromise. Looking at the report, all the machines and equipment, especially the underground pumps, which would drain water from the lower levels, were in critical condition and required immediate repair. It’s now about 45 years after the report, though the mine is said to have been under maintenance. A developer should be fully energized to tackle the New Kilembe of the 21st Century.

Jonard Asiimwe is a mining and petroleum engineer and the Executive Director, Institute of Mining Metallurgical and Petroleum Engineers Uganda. (IMMPE).