Nuclear Power Plant Isar, Germany

Spent nuclear fuel pool

Turbine of a nuclear plant

Neutrons

Neutron Moderator

Neutron Moderator

The moderator is a component that is part of nuclear reactors. It is located in the reactor core. The function of the moderator is to reduce the speed of neutrons in nuclear fission reactions.

During fission nuclear reactions, neutrons collide with fissile atoms (uranium and plutonium) present in the nuclear fuel causing fission. With each fission reaction, one or two neutrons are released at high speed.

The objective to maintain a chain fission reaction is that these neutrons hit other fissile atoms but at such a speed it is very difficult. The objective of…

Nuclear Fission

Nuclear Fission

We can obtain energy manipulating one or several nuclei of atoms throught two different methods: attaching the cores from different atoms (the nuclear fusion) or splitting a given atom nuclei (the nuclear fission).

In nuclear energy, nuclear fission is the action through which the nucleus of an atom is divided. The core forms different fragments with a mass equivalent to half of the original mass and two or three neutrons.

The total mass of the fragments is smaller than the original…

Isotopes

Isotopes

Isotopes are atoms whose nuclei have the same number of protons but different numbers of neutrons. Not all atoms of the same element are identical and each of these varieties corresponds to a different isotope.

Each isotope of the same element have the same atomic number (Z) but each has a different mass number (A). The atomic number is the number of protons in the atomic nucleus of the atom. The mass number is the sum of neutrons and protons of the core. This means that different isotopes of the same atom differ from each other only by the number of neutrons.

The items that can…

Nuclear Reactor

Nuclear Reactor

A nuclear reactor is a facility capable of initiating, controlling and maintaining nuclear reactions (usually nuclear fission) in chain that occur in the core of this installation.

The composition of the nuclear reactor is formed by the nuclear fuel, the refrigerant, the control elements, the structural materials and, in the case of a nuclear reactor, the nuclear moderator.

To build a nuclear reactor it is necessary to have enough nuclear fuel, which we call critical mass. Having enough critical mass means having enough fissile…

Uranium - Nuclear Fuel

Uranium - Nuclear Fuel

Uranium is the most commonly used nuclear fuel in nuclear fission reactions. It is a natural element that can be found in nature. However, in order to be able to use uranium in a nuclear reactor it must undergo some treatment.

To know the peculiarities that make uranium so different from the other substances we must first consider some basic nuclear physics.

Basic physical considerations of uranium

An atom of a nucleus and electrons surrounding this nucleus. In turn, a nucleus consists of protons and neutrons. A proton has a positive charge. A neutron has no electric charge…

Atom

Atom

The atom is a structure in which matter is organized in the physical world or in nature. The atoms form the molecules, while the atoms in turn are formed by subatomic constituents such as protons (with positive charge), neutrons (without charge) and electrons. (with negative charge).

In a graphical way, what is an atom? Let's imagine that we have a piece of iron. We split it. We still have two pieces of iron but smaller ones. We will start them again, again ... Each time we will have more smaller pieces until a moment will come, in which if we go back to…

Proton

Proton

Proton definition

A proton is a subatomic particle with a positive electric charge that lies within the atomic nucleus of atoms. The number of protons in the atomic nucleus is that which determines the atomic number of an element, as indicated in the periodic table of the elements.

The proton has +1 charge (or, alternatively, 1,602 x 10-19 coulombs), exactly the opposite of the charge -1 containing the electron. In mass, however, there is no competition because the mass of the proton is approximately 1,836 times greater than that of an electron.

The proton is…

Atomic Theory

Atomic Theory

In physics and chemistry, the atomic theory is a scientific theory of the nature of matter, which states that matter is composed of units called atoms. Atomic theory began as a philosophical concept in ancient Greece and entered the mainstream of the nineteenth century when discoveries in the field of chemistry showed that matter really behaves as if it were an atom.

The word atom originates in the atomic adjective of the ancient Greek, which means "indivisible". As explained in the history of nuclear energy. Nineteenth-century chemists began to use the term in relation to the growing…

Atomic Energy

Atomic Energy

Atomic energy comes from the atom, it is the energy that holds together neutrons and protons of the nuclei of atoms. It is also known how nuclear energy, which comes from the nucleus. The name nuclear energy is used because most of the energy of an atom resides in its nucleus.

Two parts of the atom, the nucleus and the crust are differentiated. In the cortex, an indeterminate number of electrons orbit around the nucleus. The nucleus is composed of an indeterminate number of neutrons and protons. The amount of protons in the nucleus will determine the element that the atom is treated,…

Pressurized Water Reactors

Pressurized Water Reactors

The pressurized water nuclear reactor is the type of nuclear reactor more used worldwide in the nuclear power plants of generation of electricity. At present, there are more than 230 nuclear reactors in the world made with the pressurized water system. Also known by its abbreviations PW. Its main feature is the use of water under high pressure in the primary circuit to prevent it from boiling.

Within the naval engineering the pressurized water nuclear reactor (PWR) is widely used. In fact, this model was originally designed to be used on a nuclear submarine.

Pressurized water…

Nuclear Power Plant

Nuclear Power Plant

A nuclear power plant is a facility for obtaining electrical energy using nuclear energy.

Its operation is similar to that of a thermal power plant or that of a solar thermal plant: from a source of energy thermodynamics is used to obtain heat, with the heat to get steam and with the steam to drive a turbine that will generate electricity.

The difference between the different types of electrical installations is in the energy source: a nuclear power plant uses the heat released in the nuclear fission reactions of certain atoms, in a thermal power station the heat source (thermal…

Coolant

Coolant

A coolant in a nuclear reactor is a liquid or gaseous substance that passes through the reactor core and removes heat from the nuclear fission reaction.

In the double-circuit power reactors, the reactor coolant enters the steam generator, which produces steam that drives the turbines, and in the single-circuit reactors the coolant (steam or gas) can serve as the working fluid of the cycle of the turbine. In research (for example, materials science) and special reactors (for example, in reactors for the accumulation of radioactive isotopes) the coolant only cools the reactor, the…

Atomic Nucleus

Atomic Nucleus

The atomic nucleus is the small central part of the atom, with a positive electric charge and in which most of the mass of the atom is concentrated. Ernest Ruthenford discovered it in 1911. After the discovery of the neutron, in 1932, the atomic nucleus model was quickly developed by Dmitri Ivanenko and Werner Heisenberg.

The major subatomic particles in the nuclei of atoms are protons and neutrons or nucleons (except ordinary hydrogen, which contains only one proton). A single chemical element is characterized by the number of protons in the nucleus that determines the total positive…

Radioactivity

Radioactivity

We define radioactivity as the spontaneous emission of particles (alpha particles, beta particles, neutrons) or radiations (range, K capture), or both at the same time, coming from the disintegration of certain nuclides that form them, due to an arrangement in its internal structure.

Radioactive decay occurs in unstable atomic nuclei, that is, those that do not have enough binding energy to keep the nucleus together due to an excess of protons or neutrons.

Radioactivity can be natural or artificial. In natural radioactivity, the substance already has it in the natural state. In…

Types Of Nuclear Reactors

Types Of Nuclear Reactors

Nuclear reactors can be classified according to different criteria. One of the criteria is the purpose for which they will be used. In this regard we distinguish the types of nuclear reactors used for civilian purposes, for military purposes or for research purposes.

Civil nuclear reactors use nuclear energy to generate power for electricity; military reactors create materials that can be used in nuclear weapons such as the atomic bomb; and research nuclear reactors used to develop weapons or energy production technology, for development purposes, for nuclear physics…

History Of Nuclear Energy

History Of Nuclear Energy

To explain the history of nuclear energy we could distinguish three major stages:

  • Physical and chemical scientific studies of the elements.
  • The development of the nuclear bomb during World War II.
  • Use of nuclear energy in the civil field.

Scientific studies cover this whole period since the first Greek philosophers began to define atoms, until the development of the first nuclear bomb. In this process, different scientists discover the presence of electrons, neutrons and protons and properties that make one atom more radioactive than another.

Chernobyl Nuclear Accident

Chernobyl Nuclear Accident

The nuclear accident in Chernobyl (1986) is by far the most serious nuclear accident in the history of nuclear energy. It was classified as level 7 (severe nuclear accident) of the INES scale, the highest value. Although it is the same level at the Fukushima nuclear accident was classified, the consequences of the Chernobyl accident were still far worse.

The Chernobyl nuclear power plant is located near the town of Prypyat, 18km from the city of Chernobyl.

At the time of the Chernobyl nuclear power plant accident provided 4 reactors in operation and two more were under construction.

Nuclear Fusion

Nuclear Fusion

Nuclear fusion is a nuclear reaction through which two light nuclei of atoms, usually hydrogen and its isotopes (deuterium and tritium), are combined forming a heavier nucleus. This binding is usually accompanied by the emission of particles (in case of deuterium nuclei one neutron is emitted). This nuclear fusion reaction releases or absorbs a lot of energy in the form of gamma rays and kinetic energy of the emitted particles.This large amount of energy transforms matter to a plasma state.

The nuclear fusion reactions can emit or absorb…