Перспективы урана как надежного источника энергии

Материал из Бюллетеня МАГАТЭ

По данным Международного энергетического агентства, к 2030 году глобальное потребление энергии может возрасти на 18 %, а к 2050 году — на 39 %. Возрастет потребность в различных источниках энергии, в том числе ядерной энергетике и, следовательно, в уране.

Хотя запасов урана хватит по меньшей мере на 100 лет, в настоящее время ведутся поиски альтернативных методов использования мировых урановых ресурсов. (Фото: «Орано»)

По данным Международного энергетического агентства, к 2030 году глобальное потребление энергии может возрасти на 18 %, а к 2050 году — на 39 %. Возрастет потребность в различных источниках энергии, в том числе ядерной энергетике и, следовательно, в уране.

«По мере ввода новых и вывода устаревших энергетических реакторов надежность поставок и эффективное освоение ресурсов урана станут важнейшими факторами, от которых в ближайшие десятилетия будут зависеть энергопоставки, — заявила г-жа Адриенн Хэнли, специалист по урановым ресурсам МАГАТЭ. — Мы полагаем, что топливо на основе урана останется основным и надежным источником энергии для низкоуглеродной ядерной энергетики. То, как мы будем использовать этот вид топлива, в значительной степени будет зависеть от появления новых технологий и стратегий рационального использования природных ресурсов».

Даже по низкому сценарию будущего ядерной энергетики МАГАТЭ, согласно которому ее доля снизится с сегодняшних 11 % от энергетической корзины до всего 6 % к 2015 году, объем генерирующих мощностей возрастет на 24 %. Согласно высокому сценарию, объем ядерной энергетики увеличится в 2,8 раз, а ее доля глобального энергетического рынка возрастет до 13,7 % к 2050 году.

В связи с тем, что в ядерной энергетике развиваются новые технологии, некоторые из которых потребляют меньше урана или могут в качестве топлива использовать материалы, которые сейчас относятся к ядерным отходам, увеличение производства ядерной энергии не обязательно повлечет пропорциональное увеличение спроса на добываемый уран. Тем не менее, ожидается, что спрос на него все равно возрастет.

Каким образом отрасль будет удовлетворять растущий спрос? Хотя запасов урана, доступных с использованием технологий, применяющихся в горнодобывающей промышленности, хватит по крайней мере на 100 лет, в настоящее время ведутся исследования альтернативных методов добычи мировых запасов урана.

Uranium from the sea

One such method consists of extracting uranium from seawater, which contains more than four billion tonnes of dissolved uranium — far outweighing the volume of reasonably assured supply from mining activities on land. Extraction from the sea also promises to be an environmentally friendly and sustainable way to supplement the global uranium supply.

Extracting usable quantities of uranium from seawater is theoretically simpler than from ore. The uranium found in seawater is created by steady chemical reactions between the water and rocks that contain uranium. And when uranium is taken from the seawater, the same amount later leaches from the rocks to replace it. Success in this research would mean a virtually unlimited supply.

Methods under development for extracting uranium from seawater involve infusing fibres made of polyethylene, a common plastic, with amidoxime, a substance that attracts uranium dioxide and binds it to the fibre. There are approximately three milligrams of uranium per cubic metre of water, or about the equivalent of a grain of salt per litre. After about a month of soaking them, scientists can remove the fibres and treat them with an acid that collects the uranium and makes the fibres suitable
for reuse. 

Although this method has been researched for decades, its commercialization has not yet proven to be economical given the low price of uranium and the abundance of supply from conventional mines. Over the past five years, the cost of uranium extraction from the sea dropped by a factor of four to US $440 per kilogramme. But the price needs to fall significantly further for this method to be usable on a commercial scale.

While there is enough uranium for at least 100 years, research is under way to identify different methods for tapping into the Earth’s uranium resources. (Photo: Orano)

Using uranium more efficiently

Equally important as sustainable uranium acquisition is the efficient use and management of the uranium. Interest worldwide has increased in the use of small modular reactors (SMRs), thanks to their ability to generate flexible power for a wider range of uses and applications. One advantage of SMRs is that — depending on the technology used — less uranium could be required for the same output.

Large scale SMR deployment could significantly alter demand and the predictability of the market. Today, the industry caters to a constant demand from large reactors, whose supply needs are different from those of small reactors.

In addition to exploring new technologies for obtaining more uranium, the nuclear energy industry will have to examine practices in resource management to ensure sustainability, Hanly said. The IAEA has been working with the United Nations Economic Commission for Europe (UNECE) in recent years to address issues in resource management, including socioeconomic viability, technological feasibility and confidence in estimates.

“Uranium has to be seen as a low-carbon fuel that can help realize many of the United Nations Sustainable Development Goals and climate commitments,” said Harikrishnan Tulsidas, Economic Affairs Officer at UNECE. “New technologies will have a critical role to play in making uranium production sustainable.”

Uranium from the sea

One such method consists of extracting uranium from seawater, which contains more than four billion tonnes of dissolved uranium — far outweighing the volume of reasonably assured supply from mining activities on land. Extraction from the sea also promises to be an environmentally friendly and sustainable way to supplement the global uranium supply.

Extracting usable quantities of uranium from seawater is theoretically simpler than from ore. The uranium found in seawater is created by steady chemical reactions between the water and rocks that contain uranium. And when uranium is taken from the seawater, the same amount later leaches from the rocks to replace it. Success in this research would mean a virtually unlimited supply.

Methods under development for extracting uranium from seawater involve infusing fibres made of polyethylene, a common plastic, with amidoxime, a substance that attracts uranium dioxide and binds it to the fibre. There are approximately three milligrams of uranium per cubic metre of water, or about the equivalent of a grain of salt per litre. After about a month of soaking them, scientists can remove the fibres and treat them with an acid that collects the uranium and makes the fibres suitable
for reuse. 

Although this method has been researched for decades, its commercialization has not yet proven to be economical given the low price of uranium and the abundance of supply from conventional mines. Over the past five years, the cost of uranium extraction from the sea dropped by a factor of four to US $440 per kilogramme. But the price needs to fall significantly further for this method to be usable on a commercial scale.

While there is enough uranium for at least 100 years, research is under way to identify different methods for tapping into the Earth’s uranium resources. (Photo: Orano)

Using uranium more efficiently

Equally important as sustainable uranium acquisition is the efficient use and management of the uranium. Interest worldwide has increased in the use of small modular reactors (SMRs), thanks to their ability to generate flexible power for a wider range of uses and applications. One advantage of SMRs is that — depending on the technology used — less uranium could be required for the same output.

Large scale SMR deployment could significantly alter demand and the predictability of the market. Today, the industry caters to a constant demand from large reactors, whose supply needs are different from those of small reactors.

In addition to exploring new technologies for obtaining more uranium, the nuclear energy industry will have to examine practices in resource management to ensure sustainability, Hanly said. The IAEA has been working with the United Nations Economic Commission for Europe (UNECE) in recent years to address issues in resource management, including socioeconomic viability, technological feasibility and confidence in estimates.

“Uranium has to be seen as a low-carbon fuel that can help realize many of the United Nations Sustainable Development Goals and climate commitments,” said Harikrishnan Tulsidas, Economic Affairs Officer at UNECE. “New technologies will have a critical role to play in making uranium production sustainable.”