10 Examples of Combustion - encyclopedia

Content

Combustion phases
Types of combustion
Examples of combustion

Is called combustion normally to all kinds of exothermic chemical reaction (generating heat), relatively fast and that develops in gaseous or heterogeneous phases (liquid-gaseous or solid-gaseous), both in a controlled way (as in internal combustion engines) and uncontrolled (in explosions).

However, traditional approaches (classical theory) to combustion understand it as a rapid oxidation process of fuel elements, consisting mainly of hydrogen, carbon, and sometimes sulfur, which takes place in the presence of oxygen and releases large amounts of thermal energy.

In these reactions by-products such as carbon dioxide (CO₂) and water vapor, among other solid waste from the process, depending on the nature of the fuel (the substance that is consumed) and the oxidizer (the substance that promotes the reaction) involved.

In fact, fire is nothing other than the violent oxidation of combustible matter.

See also: Examples of Fuels in Everyday Life

Combustion phases

Every combustion process is actually a set of fast and simultaneous reactions, which are usually taken as one, comprising the following stages or phases:

A first stage or pre-reaction. The hydrocarbons of fuel decompose and react with oxygen in the air, thus forming radicals, very molecularly unstable compounds. This starts a chain reaction of compound appearance and disappearance, which tends to create more than it destroys..
Second stage or oxidation. Here most of the heat energy is generated, when oxygen reacts with radicals and initiates a process of electron displacement. The previous accumulation of radicals leads to a massive and violent reaction known as an explosion..
Third stage. The oxidation of the radicals is completed and make up the molecules of the gases that will be released in combustion.

Types of combustion

Three different types of combustion are commonly distinguished, namely:

Complete or perfect. This is the name given to the reactions in which the combustible materials, byproducing oxygenated compounds such as carbon dioxide, sulfur dioxide or water vapor.
Stoichiometricor neutral. This is the name of an ideal complete combustion, which uses just the right amounts of air for its reaction and which, therefore, generally occurs in a controlled laboratory environment.
Incomplete. In this case, half-oxidized (unburned) compounds appear in the combustion gases, such as carbon monoxide (CO), hydrogen, carbon particles, etc.

Examples of combustion

A bonfire. A typical example is the bonfire, which has accompanied man throughout the centuries. It's about a lot of organic material (usually firewood, dry leaves, paper, etc.) piled up to concentrate the heat and keep the reaction alive, in contact with oxygen and in the initial presence of heat (a phosphor, for example).
A match. The most emblematic case of combustion is that of phosphorus (matches, matches, etc.), which is nothing more than a wooden or waxed paper stick, with a head of phosphorus and sulfur that when scraped against a rough surface, heated by the friction and initiates a combustion that generates a flame.
A gas stove. Domestic kitchens operate on the combustion of a flammable gas, usually a mixture of propane (C₃H₈) and butane (C₄H₁₀), extracted from a pipe or a cylinder and put in contact with the air and with an initial charge of heat energy (such as the pilot flame).
Strong bases and organic matter. The strong bases such as caustic soda, caustic potash and other corrosive agents of extreme pH, can cause a drastic oxidation reaction when they come into contact with organic matter, thus being able to burn on contact and even start fires, as this reaction is very exothermic.
The wisps. Known by this name since ancient times and associated with spirits and other manifestations supernatural, these spontaneous flames that take place in swamps and bogs of abundant organic matter in decomposition (and therefore many hydrocarbon gases) is an example of combustion in nature.
Fireworks. Those spectacular displays of color, sound and light that are so enjoyed at Christmas or national holidays, represent small detonations and combustion of gunpowder and other elements contained in a cylindrical cartridge. As the wick is lit, the fire eventually introduces the heat load necessary to initiate combustion and this to detonate the gunpowder in a chain reaction.
The shot from a revolver. In a similar way to the previous case, firearms operate based on the introduction of a heat spark, the product of the blow of a small hammer on the rear metal of the bullet, which initiates the combustion and subsequent explosion of the powder contained within. turn on ammo. This reaction is so violent that it generates the force necessary to throw the lead forward with great force.
An internal combustion engine. The engines of automobiles, boats and other vehicles that operate with fossil fuels (diesel, gasoline, kerosene) are a daily example of controlled combustion. These consume the hydrocarbons in the fuel and generate controlled explosions that are transformed into movement, as well as gases that are released into the atmosphere.
Cremation of a corpse. A ritual practice inherited from ancient civilizations, the cremation of the dead consists of subjecting the corpse of a human being or an animal to the action of the heat of an oven, thus inducing the combustion of the organic matter that composes it and of which it usually not much more than solid waste (ash) remains.
The forest fires. Like campfires or wood stoves, wildfires are uncontrolled combustions that spread across acres of trees and leaves and flammable organic matter, unless something is done to stop them. In many cases they are the result of the injection of heat product of the action of the sun intensified by the glass of an abandoned bottle, which literally lights the wick of the fire.