Topic2. radioactive waste. The problem of radioactive waste What substances are nuclear waste

20.06.2020

Radioactive waste (RW) is a by-product of technical activity containing biologically hazardous radionuclides. RAW is formed:

at all stages of nuclear energy (from fuel production to the operation of nuclear power plants (NPPs), including nuclear power plants (NPPs);
in the production, use and destruction of nuclear weapons in the production and use of radioactive isotopes.

RW is classified according to various criteria (Fig. 1): according to the state of aggregation, according to the composition (type) of radiation, according to the lifetime (half-life T 1/2), by activity (radiation intensity).

Among RW, liquid and solid are considered to be the most common in terms of aggregate state, mainly arising during the operation of nuclear power plants, other nuclear power plants and at radiochemical plants for the production and processing of nuclear fuel. Gaseous radioactive waste is generated mainly during the operation of nuclear power plants, radiochemical plants for fuel regeneration, as well as during fires and other emergencies at nuclear facilities.

Radionuclides contained in radioactive waste undergo spontaneous (spontaneous) decay, during which one (or several in succession) of the types of radiation occurs: a -radiation (flux a -particles - doubly ionized helium atoms), b -radiation (flow of electrons), g -radiation (hard short-wave electromagnetic radiation), neutron radiation.

The processes of radioactive decay are characterized by an exponential law of decrease in time of the number of radioactive nuclei, while the lifetime of radioactive nuclei is characterized by half-lifeT 1/2 - the period of time during which the number of radionuclides will decrease by half on average. The half-lives of some radioisotopes formed during the decay of the main nuclear fuel - uranium-235 - and representing the greatest danger to biological objects, are given in the table.

Table

Half-lives of some radioisotopes

The United States, which at one time was actively testing atomic weapons in the Pacific Ocean, used one of the islands for disposal of radioactive waste. The containers with plutonium stored on the island were covered with powerful reinforced concrete shells with warning inscriptions visible for several miles: stay away from these places for 25 thousand years! (Recall that the age of human civilization is 15 thousand years.) Some containers were destroyed under the influence of incessant radioactive decays, the level of radiation in coastal waters and bottom rocks exceeds the permissible limits and is dangerous for all living things.

Radioactive radiation causes the ionization of atoms and molecules of matter, including the matter of living organisms. The mechanism of the biological action of radioactive radiation is complex and not fully understood. Ionization and excitation of atoms and molecules in living tissues, occurring when they absorb radiation, is only the initial stage in a complex chain of subsequent biochemical transformations. It has been established that ionization leads to the breaking of molecular bonds, changes in the structure of chemical compounds and, ultimately, to the destruction of nucleic acids and proteins. Under the action of radiation, cells are affected, primarily their nuclei, the ability of cells to normal division and metabolism in cells are disrupted.

Hematopoietic organs (bone marrow, spleen, lymphatic glands), epithelium of mucous membranes (in particular, intestines), and thyroid gland are most sensitive to radiation exposure. As a result of the action of radioactive radiation on organs, severe diseases occur: radiation sickness, malignant tumors (often fatal). Irradiation has a strong effect on the genetic apparatus, leading to the appearance of offspring with ugly deviations or congenital diseases.

Rice. 2

A specific feature of radioactive radiation is that they are not perceived by the human senses and even at lethal doses do not cause pain in him at the time of exposure.

The degree of biological effects of radiation depends on the type of radiation, its intensity and duration of exposure to the body.

The unit of radioactivity in the SI system of units is becquerel(Bq): 1 Bq corresponds to one act of radioactive decay per second (non-systemic unit - curie (Ci): 1 Ci = 3.7 10 10 decay acts per 1 s).

absorbed dose (or radiation dose) is the energy of any type of radiation absorbed by 1 kg of matter. The unit of dose in the SI system is gray(Gy): at a dose of 1 Gy in 1 kg of a substance, when absorbing radiation, energy of 1 J is released (non-systemic unit - glad: 1 Gy = 100 rad, 1 rad = 1/100 Gy).

The radioactive sensitivity of living organisms and their organs is different: the lethal dose for bacteria is 10 4 Gy, for insects - 10 3 Gy, for humans - 10 Gy. The maximum dose of radiation that does not cause harm to the human body with repeated exposure is 0.003 Gy per week, with a single exposure - 0.025 Gy.

The equivalent dose of radiation is the main dosimetric unit in the field of radiation safety, introduced to assess the possible damage to human health from chronic exposure. The SI unit of equivalent dose is sievert(Sv): 1 Sv is the dose of radiation of any kind that produces the same effect as the reference X-ray radiation in 1 Gy, or in 1 J/kg, 1 Sv = 1 Gy = 1 J/kg (non-systemic unit - rem(biological equivalent of a roentgen), 1 Sv = 100 rem, 1 rem = 1/100 Sv).

The energy of an ionizing radiation source (IRS) is usually measured in electron volts (eV): 1 eV = 1.6 10 -19 J, it is permissible for a person to receive no more than 250 eV from IRS per year (single dose - 50 eV).

unit of measurement x-ray(P) is used to characterize the state of the environment subjected to radioactive contamination: 1 P corresponds to the formation of 2.082 million pairs of ions of both signs in 1 cm 3 of air under normal conditions, or 1 P = 2.58 10 -4 C / kg (C - pendant) .

Natural radioactive background - the permissible equivalent dose rate from natural radiation sources (the Earth's surface, atmosphere, water, etc.) in Russia is 10-20 μR / h (10-20 μrem / h, or 0.1-0.2 µSv/h).

Radioactive contamination has a global character not only in terms of the spatial scale of its influence, but also in terms of the duration of its action, threatening people's lives for many decades (the consequences of the Kyshtym and Chernobyl accidents) and even centuries. Thus, the main "stuffing" of atomic and hydrogen bombs - plutonium-239 (Pu-239) - has a half-life of 24 thousand years. Even micrograms of this isotope, once in the human body, cause cancer in various organs; three "oranges" of plutonium-239 could potentially destroy all of humanity without any nuclear explosions.

In view of the absolute danger of radioactive waste for all living organisms and for the biosphere as a whole, they need to be decontaminated and (or) thoroughly buried, which is still an unresolved problem. The problem of combating radioactive contamination of the environment is brought to the fore among other environmental problems due to its enormous scale and especially dangerous consequences. According to the famous ecologist A.V. Yablokov, "environmental problem number 1 in Russia - its radioactive contamination."

The unfavorable radiological situation in certain regions of the world and Russia is primarily the result of a long-term arms race during the Cold War and the creation of weapons of mass destruction.

For the production of weapons-grade plutonium (Pu-239) in the 1940s. the first nuclear power plants were built - reactors (tens of tons of Pu-239 are required for nuclear weapons; one ton of this "explosive" is produced by a slow-neutron nuclear reactor with a capacity of 1000 MW - one unit of a conventional nuclear power plant of the Chernobyl type has such power). Tests by nuclear powers (the United States, the USSR, and then Russia, France and other countries) of nuclear weapons in the atmosphere and under water, underground nuclear explosions for “peaceful” purposes, which are now moratoriumed, have led to severe pollution of all components of the biosphere.

Under the program "Peaceful atom" (the term was proposed by the American President D. Eisenhower) in the 1950s. NPP construction began first in the USA and the USSR, and then in other countries. At present, the share of nuclear power plants in the production of electrical energy in the world is 17% (in the structure of the Russian electric power industry, the share of nuclear power plants is 12%). There are nine nuclear power plants in Russia, of which eight are located in the European part of the country (all stations were built during the existence of the USSR), including the largest - Kursk - with a capacity of 4000 MW.

In addition to the arsenal of nuclear weapons (bombs, mines, warheads), nuclear power plants that produce explosives, and nuclear power plants, the sources of radioactive contamination of the environment in Russia (and adjacent territories) are:

nuclear icebreaker fleet, the most powerful in the world;
submarine and surface warships with power nuclear power plants (and carrying nuclear weapons);
ship repair and shipyards of such ships;
enterprises involved in the processing and disposal of radioactive waste of the military-industrial complex (including decommissioned submarines) and nuclear power plants;
sunken nuclear ships;
spacecraft with nuclear power plants on board;
RW disposal sites.

It should be added to this list that the radiation situation in Russia is still determined by the consequences of accidents that occurred in 1957 at the Mayak Production Association (PO) (Chelyabinsk-65) in Kyshtym (Southern Urals) and in 1986 at the Chernobyl NPP (ChNPP) 1 .

Until now, agricultural land in the Republic of Mordovia and 13 regions of the Russian Federation on an area of 3.5 million hectares is still subject to radioactive contamination as a result of the accident at the Chernobyl nuclear power plant. (The consequences of the Kyshtym accident are discussed below.)

The total area of the radiation destabilized territory of Russia exceeds 1 million km 2 with more than 10 million people living on it. At present, the total activity of unburied radioactive waste in Russia is more than 4 billion Ci, which is equivalent in terms of the consequences of eighty Chernobyl disasters.

The most unfavorable radiation environmental situation has developed in the north of the European territory of Russia, in the Ural region, in the south of the West and East Siberian regions, in the places where the Pacific Fleet is based.

The Murmansk Region surpasses all other regions and countries in terms of the number of nuclear facilities per capita. Objects using various nuclear technologies are widespread here. Of the civilian facilities, this is primarily the Kola NPP (KAES), which has four power units (two of them are approaching the end of their resource). About 60 enterprises and institutions use various radioisotope technological control devices. Murmansk Atomflot has seven icebreakers and one lighter carrier with 13 reactors.

The main number of nuclear facilities is associated with the armed forces. The Northern Fleet is armed with 123 nuclear-powered ships with 235 nuclear reactors; coastal batteries include a total of 3-3.5 thousand nuclear warheads.

Extraction and processing of nuclear raw materials is carried out on the Kola Peninsula by two specialized mining and processing plants. Radioactive waste generated during the production of nuclear fuel, during the operation of the KNPP and ships with nuclear power plants, accumulate directly on the territory of the KNPP and at special enterprises, including military bases. Low-level radioactive waste from civilian enterprises is buried near Murmansk; Waste from the KNPP after holding at the station is sent for processing to the Urals; part of the nuclear waste of the navy is temporarily stored on floating bases.

A decision was made to create special RW repositories for the needs of the region, in which already accumulated waste and newly generated waste will be buried, including those that will be generated during the decommissioning of the first stage of the KNPP and ship nuclear power plants.

In the Murmansk and Arkhangelsk regions, up to 1 thousand m 3 of solid and 5 thousand m 3 of liquid RW are formed annually. The indicated level of waste has been maintained for the last 30 years.

Since the late 1950s to 1992, the Soviet Union disposed of solid and liquid radioactive waste with a total activity of 2.5 million Ci in the Barents and Kara Seas, including 15 reactors from nuclear submarines (NPS), three reactors from the Lenin icebreaker (of which 13 were emergency nuclear submarine reactors, including six with unloaded nuclear fuel). Flooding of nuclear reactors and liquid radioactive waste also occurred in the Far East: in the Sea of Japan and the Sea of Okhotsk and off the coast of Kamchatka.

Nuclear submarine accidents create a dangerous radiological situation. Of these, the most famous tragedy of the nuclear submarine "Komsomolets" (April 7, 1989), which received worldwide resonance, resulted in the death of 42 crew members, and the boat lay on the ground at a depth of 1680 m near Bear Island in the Barents Sea, 300 nautical miles from coast of Norway. The reactor core of the boat contains approximately 42 thousand Ki strontium-90 and 55 thousand Ki cesium-137. In addition, the boat has nuclear weapons with plutonium-239.

The region of the North Atlantic, where the disaster occurred, is one of the most biologically productive in the World Ocean, is of particular economic importance and is included in the sphere of interests of Russia, Norway and a number of other countries. The results of the analyzes showed that so far the release of radionuclides from the boat into the external environment is insignificant, but a contamination zone is forming in the area of flooding. This process can be impulsive, especially dangerous is the contamination with plutonium-239 contained in the warheads of the boat. The transfer of radionuclides along the trophic chain seawater–plankton–fish threatens with serious environmental, political and economic consequences.

In the South Urals in Kyshtym, the Mayak Production Association (Chelyabinsk-65) is located, where since the late 1940s. regeneration of spent nuclear fuel. Until 1951, liquid RW arising during processing simply merged into the Techa River. Through the network of rivers: Techa-Iset-Ob, radioactive substances were carried out to the Kara Sea and with sea currents to other seas of the Arctic basin. Although such discharge was subsequently stopped, after more than 40 years, the concentration of radioactive strontium-90 in some sections of the Techa River exceeded the background by 100–1000 times. Since 1952, nuclear waste has been dumped into Lake Karachay (named technical reservoir No. 3) with an area of 10 km2. Due to the heat generated by the waste, the lake eventually dried up. Backfilling of the lake with soil and concrete began; for the final backfill, according to calculations, ~800 thousand m of rocky soil will still be required at a cost of 28 billion rubles (in 1997 prices). However, a lens filled with radionuclides was formed under the lake, the total activity of which is 120 million Ci (almost 2.5 times higher than the radiation activity during the explosion of the 4th Chernobyl power unit).

Recently it became known that in 1957 a serious radiation accident occurred at the Mayak Production Association: as a result of the explosion of a container with radioactive waste, a cloud with a radioactivity of 2 million Ci was formed, stretching for 105 km in length and 8 km in width. Serious radiation contamination (approximately 1/3 of Chernobyl) was subjected to an area of 15 thousand km 2, which was inhabited by more than 200 thousand people. A reserve was created on the radiation-contaminated territory, where observations of the living world were carried out for decades under conditions of increased radiation. Unfortunately, the data of these observations were considered secret, which made it impossible to give the necessary medical and biological recommendations in the liquidation of the Chernobyl accident. Accidents at "Mayak" occurred many times, the last time - in 1994. At the same time, as a result of the partial destruction of the radioactive waste storage near Petropavlovsk-Kamchatsky, a temporary increase in radiation compared to the background by 1000 times occurred.

Up to now, up to 100 million Ci of liquid radioactive waste are generated annually at the Mayak Production Association, some of which are simply dumped into surface water bodies. Solid radioactive waste is stored in trench-type burial grounds that do not meet safety requirements, as a result of which more than 3 million hectares of land are radioactively contaminated. In the zone of influence of the Mayak Production Association, the levels of radioactive contamination of air, water and soil are 50–100 times higher than the average values for the country; an increase in the number of oncological diseases and childhood leukemia was noted. The enterprise has begun construction of complexes for vitrification of high-level and bituminization of medium-level radioactive waste, as well as trial operation of a metal-concrete container for long-term storage of spent nuclear fuel from RBMK-1000 series reactors (reactors of this type were installed at the Chernobyl nuclear power plant).

The total radioactivity of existing radioactive waste in the Chelyabinsk zone, according to some estimates, reaches a huge figure - 37 billion GBq. This amount is enough to turn the entire territory of the former USSR into an analogue of the Chernobyl resettlement zone.

Another hotbed of "radioactive tension" in the country is the mining and chemical plant (MCC) for the production of weapons-grade plutonium and processing of radioactive waste, located 50 km from Krasnoyarsk. On the surface, it is a city without a definite official name (Sotsgorod, Krasnoyarsk-26, Zheleznogorsk) with a population of 100,000; the plant itself is located deep underground. By the way, there are similar objects (one at a time) in the USA, Great Britain, France; such a facility is under construction in China. Of course, little is known about the Krasnoyarsk Mining and Chemical Combine, except that the processing of RW imported from abroad brings in an income of $500,000 per 1 ton of waste. According to experts, the radiation situation at the mining and chemical complex is measured not in microR/h, but in mR/s! For decades, the plant has been pumping liquid radioactive waste into deep horizons (according to data for 1998, ~50 mln m The Yenisei can be traced at a distance of over 800 km.

However, burial of highly radioactive waste into underground horizons is also used in other countries: in the USA, for example, radioactive waste is buried in deep salt mines, and in Sweden - in rocks.

Radioactive pollution of the environment by nuclear power plants occurs not only as a result of emergency circumstances, but quite regularly. For example, in May 1997, during technological repairs at the Kursk NPP, a dangerous leak of cesium-137 into the atmosphere occurred.

Nuclear industry enterprises deal with the production, use, storage, transportation and disposal of radioactive substances. In other words, RW generation accompanies all stages of the nuclear power fuel cycle (Fig. 2), which imposes special requirements on ensuring radiation safety.

Uranium ore is mined in mines by underground or open pit mining. Natural uranium is a mixture of isotopes: uranium-238 (99.3%) and uranium-235 (0.7%). Since the main nuclear fuel is uranium-235, after primary processing, the ore enters the enrichment plant, where the content of uranium-235 in the ore is brought to 3–5%. Chemical processing of fuel consists in obtaining enriched uranium hexafluoride 235 UF 6 for the subsequent production of fuel rods (fuel elements).

The development of uranium deposits, like any other branch of the mining industry, degrades the environment: large areas are taken out of economic use, the landscape and hydrological regime change, air, soil, surface and groundwater are polluted with radionuclides. The amount of radioactive waste at the stage of primary processing of natural uranium is very high and amounts to 99.8%. In Russia, mining and primary processing of uranium is carried out only at one enterprise - the Priargunsky Mining and Chemical Association. At all uranium ore mining and processing enterprises that have been operating until recently, 108 m 3 of radioactive waste with an activity of 1.8 10 5 Ci is located in dumps and tailings.

Fuel elements, which are metal rods containing nuclear fuel (3% uranium-235), are placed in the core of a nuclear power plant reactor. Various types of uranium-235 fission chain reactions are possible (difference in the resulting fragments and the number of emitted neutrons), for example, such:

235U+1 n ® 142 Ba + 91 Kr + 31 n,
235U+1 n ® 137 Te + 97 Zr + 21 n,
235U+1 n ® 140 Xe + 94 Sr + 21 n.

The heat released during the fission of uranium heats the water flowing through the core and washing the rods. After about three years, the content of uranium-235 in fuel rods drops to 1%, they become inefficient heat sources and need to be replaced. Each year, a third of the fuel rods are removed from the core and replaced with new ones: for a typical nuclear power plant with a capacity of 1000 MW, this means the annual removal of 36 tons of fuel rods.

During nuclear reactions, fuel elements are enriched with radionuclides - fission products of uranium-235, and also (through a series of b-decays) plutonium-239:

238U+1 n® 239 U(b ) ® 239 Np(b ) ® 239 Pu.

Spent fuel rods are transported from the core through an underwater channel to storage facilities filled with water, where they are stored in steel canisters for several months, until most of the highly toxic radionuclides (in particular, the most dangerous iodine-131) decay. After that, the fuel rods are sent to fuel regeneration plants, for example, to obtain plutonium cores for fast neutron nuclear reactors or weapons-grade plutonium.

Liquid waste from nuclear reactors (in particular, water from the primary circuit, which must be renewed) after processing (evaporation) is placed in concrete storage facilities located on the territory of the nuclear power plant.

A certain amount of radionuclides during the operation of nuclear power plants is released into the air. Radioactive iodine-135 (one of the main decay products in an operating reactor) does not accumulate in spent nuclear fuel, since its half-life is only 6.7 hours, but as a result of subsequent radioactive decays it turns into xenon-135 radioactive gas, which actively absorbs neutrons and therefore preventing a chain reaction. To prevent "xenon poisoning" of the reactor, xenon is removed from the reactor through tall pipes.

The generation of waste at the stages of processing and storage of spent nuclear fuel has already been discussed. Unfortunately, all existing and applied methods of RW neutralization in the world (cementing, vitrification, bituminization, etc.), as well as solid RW incineration in ceramic chambers (as at NPO Radon in the Moscow Region) are ineffective and pose a significant danger to the environment. .

The problem of disposal and disposal of radioactive waste from nuclear power plants is becoming especially acute now, when it is time to dismantle the majority of nuclear power plants in the world (according to the IAEA 2 , these are more than 65 nuclear power plant reactors and 260 reactors used for scientific purposes). It should be noted that during the operation of a nuclear power plant, all elements of the plant become radioactively hazardous, especially the metal structures of the reactor zone. The dismantling of nuclear power plants in terms of cost and time is comparable to their construction, while there is still no acceptable scientific, technical and environmental technology for dismantling. An alternative to dismantling is sealing the station and protecting it for 100 years or more.

Even before the end of the fire at the Chernobyl nuclear power plant, the laying of a tunnel under the reactor began, the creation of a recess under it, which was then filled with a multi-meter layer of concrete. Both the block and the territories adjacent to it were poured with concrete - this is a “miracle of construction” (and an example of heroism without quotes) of the 20th century. called "sarcophagus". The exploding 4th power unit of the Chernobyl nuclear power plant is still the world's largest and most dangerous poorly equipped radioactive waste storage facility!

When using radioactive materials in medical and other research institutions, a significantly smaller amount of radioactive waste is generated than in the nuclear industry and the military-industrial complex - this is several tens of cubic meters of waste per year. However, the use of radioactive materials is expanding, and with it the volume of waste is increasing.

The radioactive waste problem is an integral part of the “Agenda for the 21st Century” adopted at the World Summit on Earth Problems in Rio de Janeiro (1992) and the “Action Program for the Further Implementation of the “Agenda for the 21st Century””, adopted by Special Session of the United Nations General Assembly (June 1997). The latter document, in particular, outlines a system of measures to improve the methods of radioactive waste management, to expand international cooperation in this area (exchange of information and experience, assistance and transfer of relevant technologies, etc.), to tighten the responsibility of states for ensuring safe storage and removal of radioactive waste.

The Program of Action acknowledges the deterioration of general trends in the sustainable development of the world, but expresses the hope that by the next international environmental forum, scheduled for 2002, tangible progress will be noted in ensuring sustainable development aimed at creating favorable living conditions for future generations.

E.E. Borovsky

________________________________
1 All the data below are taken from open publications in the state reports “On the state of the natural environment of the Russian Federation” of the State Committee of the Russian Federation for Environmental Protection and in the Russian ecological newspaper “Green World” (1995–1999).
2 International Atomic Energy Agency.

Radioactive waste has become an extremely acute problem of our time. If at the dawn of the development of energy, few people thought about the need to store waste material, now this task has become extremely urgent. So why is everyone so worried?

Radioactivity

This phenomenon was discovered in connection with the study of the relationship between luminescence and x-rays. At the end of the 19th century, during a series of experiments with uranium compounds, the French physicist A. Becquerel discovered a hitherto unknown substance passing through opaque objects. He shared his discovery with the Curies, who studied it closely. It was the world-famous Marie and Pierre who discovered that all uranium compounds, like pure uranium itself, as well as thorium, polonium and radium, have the property. Their contribution has been truly invaluable.

Later it became known that all chemical elements, starting with bismuth, are radioactive in one form or another. Scientists also thought about how the process of nuclear decay could be used to generate energy, and were able to initiate and reproduce it artificially. And to measure the level of radiation, a radiation dosimeter was invented.

Application

In addition to energy, radioactivity has been widely used in other industries: medicine, industry, scientific research and agriculture. With the help of this property, they learned to stop the spread of cancer cells, make more accurate diagnoses, find out the age of archaeological treasures, monitor the transformation of substances in various processes, etc. The list of possible applications of radioactivity is constantly expanding, so it is even surprising that the issue of disposal of waste materials has become so acute only in recent decades. But this is not just garbage that can be easily thrown into a landfill.

radioactive waste

All materials have their own lifespan. This is no exception for elements used in nuclear energy. The output is waste that still has radiation, but no longer has practical value. As a rule, used is considered separately, which can be recycled or applied in other areas. In this case, we are talking simply about radioactive waste (RW), the further use of which is not provided, therefore, they must be disposed of.

Sources and forms

Due to the variety of uses, wastes can also come in different origins and conditions. They are both solid and liquid or gaseous. Sources can also be very different, since in one form or another such waste often occurs during the extraction and processing of minerals, including oil and gas, there are also such categories as medical and industrial RW. There are also natural sources. Conventionally, all these radioactive wastes are divided into low-, medium- and high-level. The United States also distinguishes the category of transuranic radioactive waste.

Options

For quite a long time it was believed that the disposal of radioactive waste does not require special rules, it was enough just to disperse them in the environment. However, later it was discovered that isotopes tend to accumulate in certain systems, such as animal tissues. This discovery changed the opinion about radioactive waste, since in this case the probability of their movement and getting into the human body with food became quite high. Therefore, it was decided to develop some options for how to deal with this type of waste, especially for the high-level category.

Modern technologies make it possible to maximally neutralize the danger posed by RW by processing them in various ways or by placing them in a space that is safe for humans.

Vitrification. In another way, this technology is called vitrification. At the same time, radioactive waste goes through several stages of processing, as a result of which a rather inert mass is obtained, which is placed in special containers. Then these containers are sent to storage.
Synrock. This is another method of radioactive waste neutralization developed in Australia. In this case, a special complex compound is used in the reaction.
Burial. At this stage, a search is underway for suitable places in the earth's crust where radioactive waste could be placed. The most promising is the project, according to which the waste material is returned to
Transmutation. Reactors are already being developed that can turn highly radioactive waste into less dangerous substances. Simultaneously with the neutralization of waste, they are able to generate energy, so the technologies in this area are considered extremely promising.
Removal into outer space. Despite the attractiveness of this idea, it has a lot of drawbacks. First, this method is quite costly. Secondly, there is the risk of a launch vehicle crash, which could be a disaster. Finally, the clogging of outer space with such waste after a while can turn into big problems.

Disposal and storage rules

In Russia, radioactive waste management is regulated primarily by federal law and its commentaries, as well as some related documents, such as the Water Code. According to the Federal Law, all radioactive waste must be buried in the most isolated places, while pollution of water bodies is not allowed, sending into space is also prohibited.

Each category has its own regulations, in addition, the criteria for assigning waste to a particular type and all the necessary procedures are clearly defined. However, Russia has a lot of problems in this area. Firstly, the disposal of radioactive waste may very soon become a non-trivial task, because there are not so many specially equipped storage facilities in the country, and they will be filled pretty soon. Secondly, there is no single system for managing the recycling process, which seriously complicates control.

International projects

Given that the storage of radioactive waste has become the most urgent after the cessation, many countries prefer to cooperate in this matter. Unfortunately, it has not yet been possible to reach a consensus in this area, but the discussion of various programs in the UN continues. The most promising projects seem to be to build a large international storage facility for radioactive waste in sparsely populated areas, usually in Russia or Australia. However, the citizens of the latter are actively protesting against this initiative.

Consequences of irradiation

Almost immediately after the discovery of the phenomenon of radioactivity, it became clear that it negatively affects the health and life of humans and other living organisms. The studies that the Curies conducted over several decades eventually led to a severe form of radiation sickness in Maria, although she lived to be 66 years old.

This disease is the main consequence of the effects of radiation on humans. The manifestation of this disease and its severity mainly depend on the total radiation dose received. They can be quite mild, or they can cause genetic changes and mutations, thus affecting the next generations. One of the first to suffer is the function of hematopoiesis, often patients have some form of cancer. At the same time, in most cases, the treatment is quite ineffective and consists only in observing the aseptic regimen and eliminating symptoms.

Prevention

It is quite easy to prevent a condition associated with exposure to radiation - it is enough not to get into areas with its increased background. Unfortunately, this is not always possible, because many modern technologies involve active elements in one form or another. In addition, not everyone carries a portable radiation dosimeter with them to know that they are in an area where prolonged exposure can cause harm. However, there are certain measures to prevent and protect against dangerous radiation, although there are not many of them.

First, it's shielding. Almost everyone who came to x-ray a certain part of the body faced this. If we are talking about the cervical spine or the skull, the doctor suggests putting on a special apron, into which elements of lead are sewn, which does not allow radiation to pass through. Secondly, you can support the body's resistance by taking vitamins C, B 6 and P. Finally, there are special preparations - radioprotectors. In many cases they are very effective.

The law on the use of nuclear energy states that radioactive waste is substances, materials, devices and other equipment containing elevated levels of radionuclides and has lost its consumer properties, as well as unsuitable for reuse.

Under what circumstances are wastes containing radioactive elements generated?

Radioactive waste is contained in nuclear fuel, they are formed during the operation of nuclear power plants, this is one of the main sources. They can also be obtained as a result:

mining of radioactive ore;
ore processing;
production of heat release elements;
disposal of spent nuclear fuel.

During the development of nuclear weapons by the Russian armed forces, radioactive waste was also generated, such actions as the production, conservation and liquidation of objects using this material did not rehabilitate previous work with this material. As a result, there is a lot of waste generated in the process of production of nuclear materials on the territory of the country.

The navy, submarines, as well as civilian ships using nuclear reactors, also leave radioactive waste during their operation and even after their failure.

Work with radioactive waste in Russia is associated with the following industries:

In the national economy, using isotope products.
In medical or pharmaceutical institutions and laboratories.
Chemical, metallurgical and other industries working in the field of processing.
Conducting scientific experiments and research using nuclear fuel or similar elements.
Even security services, in particular, customs control.
The extraction of oil or gas also requires the use of nuclear substances, which leave behind radioactive waste.

It's important to know. Spent nuclear fuel will not fall under the category of radioactive waste, according to Russian legislation.

Division into types

The Decree from the Government of the Russian Federation made adjustments according to which radioactive waste can be:

hard;
liquid;
similar gas;

types. Classification of radioactive waste refers to solid, liquid and gas-like all elements and substances containing radionuclides. An exception is possible only if the formation is not associated with nuclear energy, and the content of radionuclides is due to the extraction or processing of natural minerals and organic raw materials with an increased level of radionuclides or near its natural source. The concentration, which, within the limits of permissible norms established by a decree of the Russian Government, does not exceed 1.

RW belonging to the type of "solid" contain man-made radionuclides, from which sources such as closed enterprises working with such substances are excluded. They are divided into four categories:

highly active;
moderately inactive;
low active;
very low activity.

RW arriving in a "liquid" state is divided into only three categories:

highly active;
medium active;
low active.

Closed, decommissioned enterprises and plants working with radionuclides belong to other RW categories.

RW classification

There is a Federal Law, for the purposes of which, the classification of radioactive waste divides them into the following types:

Disposables are substances for which the risk associated with their impact on the environment does not increase. And in the case of their removal from the place of storage for subsequent burial, the risk of their stay in the territory of their location does not exceed. This type requires rather large financial costs to perform all manipulations with it and prepare special equipment and train personnel of recycling organizations.
Special - radioactive waste, this type endangers the environment very much, in case of their extraction, transportation and further actions, for cleaning up the territory or burial in another place. Manipulations with this type are also very costly from the financial side. In cases with this species, it is safer and more economically advantageous to carry out the burial process at their primary location.

The classification of radioactive waste takes place depending on the following features:

The half-life of radionuclides is short-lived or long-lived.
Specific activity - highly active, medium active and low active RW.
Aggregate state - can be liquid, solid and gas-like.
The content of nuclear elements, present or absent in the spent material.
Spent, closed enterprises for the extraction or processing of uranium rocks that emit ionizing rays.
RW not associated with the use or work on nuclear energy. Sources of which are processing enterprises for the extraction of organic and mineral raw ores, with an increased level of radionuclides of natural origin.

The RW classification was developed by the Government of the Russian Federation to separate them into types. As well as further removal or burial at their location.

Classification system

At this time, the classification system has not been developed thoroughly and requires constant improvement, this is determined by the lack of coherence of national systems.

The basis of the classification contains the consideration of options for the subsequent disposal of radioactive waste. The main sign of which is the duration of the decay period of the nuclide, because the disposal technology directly depends on this indicator. They are buried with special strengthening solutions for at least the period that they can be dangerous to the environment. According to these data, the classification system divides all waste and hazardous substances into the following categories.

Released from control

Low and medium active radioactive waste

They contain sufficient levels of radionuclides to pose a threat to personnel working with them and to the population living in the nearest district. Sometimes they have such a high level of activity that they require refrigeration and protective measures. This category contains two groups: long-lived and short-lived species. The methods of their burial are very diverse and individual.

This type has such a quantity of radionuclides that it requires constant cooling in the process of working with it. At the end of any action, it requires reliable isolation from the biosphere, otherwise the infection process will capture the entire district, the territory in which it is located.

Typical characteristics

The waste class exempt from control (CW) has an activity level of 0.01 mSv or less, taking into account the annual dose to the population. Has no restrictions on radiological disposal.

Medium and low active (LILW) are characterized by an activity level higher than the value for CW, but at the same time the heat release in this class is below 2 W/m3.

The short-lived class (LILW-SL) has these typical characteristics. The long survivability of radionuclides has a limited concentration (less than 400 Bq/g for all packages). The places of burial of such classes are deep or near-surface storages.

Long-lived waste (LILW-LL) - the concentration of which is higher than that of short-lived waste. Such classes will be buried, they should only be in deep storages. This is one of the main requirements in relation to them.

Highly active class (HLW) - characterized by a very high concentration of long-lived radionuclides, their thermal output is more than 2 W / m3. Their burial places should also be deep storages.

RW management rules

Radioactive waste requires classification not only for the sake of separating them according to the level of danger and the ability to choose methods of disposal, but also to provide guidance on how to handle them, depending on their class. They must meet the following criteria:

Principles for ensuring the protection of human health, or at least an acceptable level of protection, depending on the radiation exposure of RW elements.
Environmental protection - an acceptable level of protection of the environment from the impact of radioactive waste.
Interdependence between all stages of RW generation, as well as handling of their elements.
Protection of the future generation by predicting the level of exposure, and rationing the amount of buried material at each repository, based on information from regulatory documents.
Do not place too high hopes on the future generation associated with the need to dispose of radioactive waste.
Control the formation and accumulation of radioactive waste, limit their accumulation and minimize the achieved level.
Prevent accidents, or mitigate the possible consequences, in the event of such situations.

Radioactive waste is the most dangerous type of waste on earth, requiring very careful and careful handling. Bringing the greatest damage to the environment, the population and all living beings, on the territory of its foundation.

Learn all about radioactive waste

Removal, processing and disposal of waste from 1 to 5 hazard class

We work with all regions of Russia. Valid license. Full set of closing documents. Individual approach to the client and flexible pricing policy.

Using this form, you can leave a request for the provision of services, request a commercial offer or get a free consultation from our specialists.

Collection, modification and disposal of radioactive waste should be carried out separately from other types of salvage. Dumping them into water bodies is prohibited, otherwise the consequences will be very sad. Radioactive waste is called waste that is not of practical value for further production. They include a set of radioactive chemical elements. According to the legislation of Russia, the subsequent use of such compounds is prohibited.

Before starting the disposal process, radioactive waste must be sorted according to the degree of radioactivity, form and period of decay. In the future, to reduce the volume of dangerous isotopes and neutralize radionuclides, they are processed by combustion, evaporation, pressing and filtration.

Subsequent processing consists in fixing liquid waste with cement or bitumen in order to harden it, or vitrification of highly radioactive waste.

The fixed isotopes are placed in special, complexly designed containers with thick walls for their further transportation to the storage site. In order to increase safety, they are supplied with additional packaging.

general characteristics

Radioactive waste can be generated from various sources, have a variety of shapes and properties.

Important characteristics of radioactive waste include:

Concentration. Parameter showing the value of specific activity. That is, this is the activity that falls on one unit of mass. The most popular unit of measure is Ki/T. Accordingly, the greater this characteristic, the more dangerous the consequences of such garbage can bring.
Half life. The duration of the decay of half of the atoms in a radioactive element. It is worth noting that the faster this period, the more energy the garbage releases, causing more harm, but in this case, the substance loses its properties faster.

Harmful substances can have a different form, there are three main states of aggregation:

gaseous. As a rule, releases from ventilation installations of organizations involved in the direct processing of radioactive materials are included here.
in liquid form. It can be liquid waste types that were formed during the processing of already used fuel. Such garbage is highly active, thereby capable of causing severe harm to the environment.
Solid form. These are glass and glassware from hospitals and research laboratories.

RW storage

The owner of a RW storage facility in Russia can be either a legal entity or a federal authority. For temporary storage, radioactive waste should be placed in a special container that ensures the conservation of spent fuel. Moreover, the material from which the container is made should not enter into any chemical reaction with the substance.

Storage facilities should be equipped with dry drums that allow short-lived radioactive waste to decay before further processing. Such a room is a repository of radioactive waste. The purpose of its operation is the implementation of temporary placement of radioactive waste for further transportation to their disposal sites.

Container for solid radioactive waste

The disposal of radioactive waste cannot do without a special container, which is called a radioactive waste container. A container for radioactive waste is a vessel used as a repository for radioactive waste. In Russia, the law establishes a huge number of requirements for such an invention.

The main ones are:

The non-returnable container is not intended for storage of liquid radioactive waste. Its structure allows it to contain only solid or hardened substances.
The body, which has a container, must be airtight and not let through even a small part of the stored waste.
After removal of the lid and decontamination, contamination should not exceed 5 particles per m 2 . It is impossible to allow more pollution, since unpleasant consequences can also affect the external environment.
The container must withstand the most severe temperature conditions from - 50 to + 70 degrees Celsius.
When draining a radioactive substance with a high temperature into a container, the container must withstand temperatures up to + 130 degrees Celsius.
The container must withstand external physical influences, in particular earthquakes.

The process of storing isotopes in Russia should provide:

Their isolation, compliance with protective measures, as well as monitoring the state of the environment. The consequences, if such a rule is violated, can be deplorable, since substances can almost instantly pollute nearby areas.
The possibility of facilitating further procedures at subsequent stages.

The main directions of the process of storage of toxic waste are:

Storage of radioactive waste with a short lifetime. Subsequently, they are discharged in strictly regulated volumes.
Storage of high-level radioactive waste until their disposal. This allows you to reduce the amount of heat generated by them, and reduce the consequences of harmful effects on the environment.

RW disposal

Problems of disposal of radioactive waste still exist in Russia. Not only the environmental protection of a person, but also the environment should be ensured. This type of activity implies a license for the use of subsoil and the right to carry out work on the development of nuclear energy. Radioactive waste disposal sites can be either federally owned or owned by the state corporation Rosatom. Today, radioactive waste disposal in the Russian Federation is carried out in specially designated areas, which are called radioactive waste disposal sites.

There are three types of disposal, their classification depends on the duration of storage of radioactive substances:

Long-term disposal of radioactive waste - ten years. Harmful elements are buried in trenches, small engineering structures made on or under the ground.
For hundreds of years. In this case, the disposal of radioactive waste is carried out in the geological structures of the mainland, this includes underground workings and natural cavities. In Russia and other countries, the creation of burial grounds at the bottom of the ocean is actively practiced.
Transmutation. A theoretically possible way to get rid of radioactive substances, which involves irradiating long-lived radionuclides and turning them into short-lived ones.

The type of burial is selected based on three parameters:

Specific activity of a substance
Packaging sealing level
Estimated shelf life

Storage facilities for radioactive waste in Russia must comply with the following requirements:

The storage facility for radioactive waste should be located away from the city. The distance between them must be at least 20 kilometers. The consequences of violating this rule are poisoning and possible death of the population.
There should be no built-up areas near the territory of the repository, otherwise there is a risk of damage to the containers.
The landfill must have a site where the waste will be buried.
The level of ground sources should be removed as far as possible. If the waste gets into the water, the consequences will be sad - the death of animals and humans
Radioactive burial grounds for solid and other wastes must have a sanitary protection zone. Its length cannot be less than 1 kilometer from livestock grazing areas and settlements.
The landfill should have a plant dealing with radioactive waste detoxification.

Waste recycling

Processing of radioactive waste is a procedure that is aimed at the direct transformation of the state of aggregation or properties of a radioactive substance in order to create convenience for the transportation and storage of waste.

Each type of garbage has its own methods for carrying out such a procedure:

For liquid - precipitation, exchange with the help of ions and distillation.
For solids - burning, pressing and calcination. The rest of the solid waste is sent to landfills.
For gaseous - chemical absorption and filtration. Further, the substances will be stored in high-pressure cylinders.

Whatever unit the product is processed, the result will be immobilized compact blocks of solid types. For immobilization and further isolation of solids, the following methods are used:

Cementing. It is applied to the garbage having low and average activity of substance. As a rule, these are solid types of waste.
Burning at high temperatures.
vitrification.
Packing in special containers. Usually such containers are made of steel or lead.

Deactivation

In connection with the active pollution of the environment, in Russia and other countries of the world they are trying to find an actual way to decontaminate radioactive waste. Yes, the disposal and disposal of solid radioactive waste give their results, but unfortunately, these procedures do not ensure the safety of the environment, and therefore are not perfect. At present, several methods of radioactive waste decontamination are practiced in Russia.

With sodium carbonate

This method is used exclusively for solid waste that has entered the soil: sodium carbonate leaches radionuclides, which are extracted from the alkali solution by ion particles that include magnetic material in their composition. Next, the chelate complexes are removed with a magnet. This method of processing solids is quite effective, but there are disadvantages.

Method problem:

The lixiviant (formula Na2Co3) has a rather limited chemical capacity. He is simply not able to extract the entire range of radioactive compounds from the solid state and convert them into liquid materials.
The high cost of the method is mainly due to the chemisorption material, which has a unique structure.

Dissolution in nitric acid

We apply the method to radioactive pulps and sediments, these substances are dissolved in nitric acid with an admixture of hydrazine. The solution is then packaged and vitrified.

The main problem is the high cost of the procedure, since the evaporation of the solution and further disposal of radioactive waste is quite expensive.

Soil elution

It is used to decontaminate soil and soil. This method is the most environmentally friendly. The bottom line is that the contaminated soil or soil is treated by elution with water, aqueous solutions with additions of ammonium salts, ammonia solutions.

The main problem is the relatively low efficiency in the extraction of radionuclides, which are associated with the soil at the chemical level.

Liquid waste decontamination

Liquid radioactive waste is a special type of waste that is difficult to store and dispose of. That is why decontamination is the best means of getting rid of such a substance.

There are three ways to clean up harmful material from radionuclides:

physical method. It implies the process of evaporation or freezing of substances. Further, sealing and placement of harmful elements in waste burial grounds is carried out.
Physico-chemical. With the help of a solution with selective extractants, extraction is carried out, i.e. removal of radionuclides.
Chemical. Purification of radionuclides using various natural reagents. The main problem of the method lies in the large amount of remaining sludge that is sent to the burial grounds.

Common problem with each method:

Physical methods - extremely high costs for evaporation and freezing solutions.
Physical - chemical and chemical - huge volumes of radioactive sludge sent to burial grounds. The burial procedure is quite expensive, it requires a lot of money and time.

Radioactive waste is a problem not only in Russia, but also in other countries. The main task of mankind at the moment is the disposal of radioactive waste and their disposal. What methods to do this, each state decides independently.

Switzerland is not engaged in its own processing and disposal of radioactive waste, but is actively developing programs for the management of such waste. If no action is taken, then the consequences can be the saddest, up to the death of mankind and animals.

Removal, processing and disposal of waste from 1 to 5 hazard class

We work with all regions of Russia. Valid license. Full set of closing documents. Individual approach to the client and flexible pricing policy.

Using this form, you can leave a request for the provision of services, request a commercial offer or get a free consultation from our specialists.

In the 20th century, the non-stop search for the ideal source of energy seemed to be over. This source was the nuclei of atoms and the reactions taking place in them - the active development of nuclear weapons and the construction of nuclear power plants began all over the world.

But the planet quickly faced the problem of processing and destroying nuclear waste. The energy of nuclear reactors carries a lot of dangers, as well as the waste of this industry. Until now, there is no carefully developed processing technology, while the sphere itself is actively developing. Therefore, safety depends primarily on proper disposal.

Definition

Nuclear waste contains radioactive isotopes of certain chemical elements. In Russia, according to the definition given in the Federal Law No. 170 “On the Use of Atomic Energy” (dated November 21, 1995), further use of such waste is not envisaged.

The main danger of materials lies in the radiation of gigantic doses of radiation, which has a detrimental effect on a living organism. The consequences of radioactive exposure are genetic disorders, radiation sickness and death.

Classification map

The main source of nuclear materials in Russia is the sphere of nuclear energy and military developments. All nuclear waste has three degrees of radiation, familiar to many from the course of physics:

Alpha - radiant.
Beta - emitting.
Gamma - emitting.

The former are considered the most harmless, as they give a harmless level of radiation, unlike the other two. True, this does not prevent them from being included in the class of the most hazardous waste.

In general, the classification map of nuclear waste in Russia divides it into three types:

Solid nuclear waste. This includes a huge amount of maintenance materials in the energy sector, staff clothing, garbage that accumulates in the course of work. Such waste is burned in kilns, after which the ashes are mixed with a special cement mixture. It is poured into barrels, sealed and sent to storage. The burial is detailed below.
Liquid. The process of operation of nuclear reactors is impossible without the use of technological solutions. In addition, this includes water that is used to treat special suits and wash workers. Liquids are carefully evaporated, and then burial occurs. Liquid waste is often recycled and used as fuel for nuclear reactors.
Elements of the design of reactors, transport and means of technical control at the enterprise constitute a separate group. Their disposal is the most expensive. To date, there are two ways out: installation of the sarcophagus or dismantling with its partial decontamination and further shipment to the repository for burial.

The map of nuclear waste in Russia also defines low-level and high-level:

Low-level waste - arise in the course of the activities of medical institutions, institutes and research centers. Here, radioactive substances are used to conduct chemical tests. The level of radiation emitted by these materials is very low. Proper disposal can turn hazardous waste into normal waste in about a few weeks, after which it can be disposed of as normal waste.
High-level waste is spent reactor fuel and materials used in the military industry to develop nuclear weapons. The fuel at the stations is a special rod with a radioactive substance. The reactor operates for approximately 12-18 months, after which the fuel must be changed. The amount of waste is simply enormous. And this figure is growing in all countries developing the field of nuclear energy. The disposal of high-level waste must take into account all the nuances in order to avoid a catastrophe for the environment and humans.

Recycling and disposal

At the moment, there are several methods for the disposal of nuclear waste. All of them have their advantages and disadvantages, but whatever one may say, they do not completely eliminate the danger of radioactive exposure.

burial

Waste disposal is the most promising method of disposal, which is especially actively used in Russia. First, the process of vitrification or "vitrification" of the waste occurs. The spent substance is calcined, after which quartz is added to the mixture, and this “liquid glass” is poured into special cylindrical steel molds. The resulting glass material is resistant to water, which reduces the possibility of radioactive elements entering the environment.

Finished cylinders are brewed and thoroughly washed, getting rid of the slightest contamination. Then they go to storage for a very long time. The repository is arranged in geologically stable areas so that the repository is not damaged.

Geological disposal is carried out at a depth of more than 300 meters in such a way that for a long time the waste does not need further maintenance.

Burning

Part of the nuclear materials, as mentioned above, is the direct results of production, and a kind of side waste in the energy sector. These are materials exposed to radiation during production: waste paper, wood, clothing, household waste.

All this is burned in specially designed furnaces, which minimize the level of toxic substances in the atmosphere. The ash, among other wastes, is cemented.

Cementing

Disposal (one of the ways) of nuclear waste in Russia by cementing is one of the most common practices. The bottom line is to place irradiated materials and radioactive elements in special containers, which are then filled with a special solution. The composition of such a solution includes a whole cocktail of chemical elements.

As a result, it is practically not exposed to the external environment, which makes it possible to achieve an almost unlimited period. But it is worth making a reservation that such a burial is possible only for the disposal of waste of an average level of danger.

Seal

A long and fairly reliable practice aimed at burying and reducing the amount of waste. It is not applicable to the processing of basic fuel materials, but allows the processing of other low-hazard wastes. This technology uses hydraulic and pneumatic presses with low pressure force.

Reapplication

The use of radioactive material in the field of energy is not fully implemented due to the specific nature of the activity of these substances. Once exhausted, the waste still remains a potential source of energy for reactors.

In the modern world, and even more so in Russia, the situation with energy resources is quite serious, and therefore the recycling of nuclear materials as fuel for reactors no longer seems unbelievable.

Today, there are methods that allow the use of spent raw materials for applications in the energy sector. Radioisotopes contained in the waste are used for food processing and as a "battery" for the operation of thermoelectric reactors.

But while the technology is still in development, and the ideal method of processing has not been found. Nevertheless, the processing and destruction of nuclear waste makes it possible to partially resolve the issue with such garbage, using it as fuel for reactors.

Unfortunately, in Russia, a similar method of getting rid of nuclear debris is practically not being developed.

Volumes

In Russia, all over the world, the volumes of nuclear waste sent for disposal amount to tens of thousands of cubic meters annually. Every year, European storage facilities receive about 45,000 cubic meters of waste, while in the United States, only one landfill in Nevada absorbs such a volume.

Nuclear waste and work related to it abroad and in Russia is the activity of specialized enterprises equipped with high-quality machinery and equipment. At the enterprises, waste is subjected to various methods of treatment described above. As a result, it is possible to reduce the volume, reduce the level of danger, and even use some waste in the energy sector as fuel for nuclear reactors.

The peaceful atom has long proved that everything is not so simple. The energy sector is developing and will continue to develop. The same can be said about the military sphere. But if we sometimes turn a blind eye to the release of other wastes, improperly disposed of nuclear waste can cause a total catastrophe for all mankind. Therefore, this issue needs to be resolved as soon as possible before it is too late.