Combustion reaction: Types of combustion and combustion fuels - WorldOfChemicals

Combustion reaction: Types of combustion and combustion fuels

Category : Process
Published by : Data Research Analyst, Worldofchemicals.com

Combustion reaction or burning is an exothermic redox chemical reaction at a high temperature between a reductant or fuel and an oxidant that produces oxidized, usually gaseous products in the form of heat and light.

Types of Combustion:

Complete and Incomplete Combustion:

1.Complete combustion:

During complete combustion, the reactant burns in oxygen and produces products that are limited. When a hydrocarbon is burnt in oxygen, the reaction yields carbon dioxide and water primarily. When different elements are burned, the products of those are primarily common chemical oxides. Carbon produces carbon dioxide, sulfur yields sulfur dioxide, and iron returns iron (III) oxide.

2.Incomplete Combustion:

This combustion takes place when there doesn’t exist enough oxygen, allowing fuel to react completely producing carbon dioxide and water. This combustion is the same as complete combustion, it also produces water, but instead of carbon dioxide, the product is carbon and carbon monoxide. In this type of combustion, products which are pyrolysis remains unburnt and contaminate the resulted smoke with noxious gases.

3.Smoldering:

This form of combustion is slow, flameless and a low-temperature combustion, undergone by the heat evolved when the surface of the fuel is directly attacked by oxygen. Typically, it is an incomplete form of the combustion reaction. Solid materials that undergo smoldering combustion includes materials like coal, cellulose, cotton, tobacco, wood, foams etc.

4.Rapid Combustion:

Rapid combustion otherwise known as fire is a type of reaction which releases a large amount of heat and light and results in a flame often. This reaction is used in the form of machinery like internal combustion engines and thermobaric weapons. This combustion is intermittently known as explosion combustion.

5.Spontaneous combustion:

It is a type of combustion that occurs through self-healing, pursued by thermal runaway and then, finally ignition. Example, phosphorous ignites on itself at room temperature without heat application.

6.Turbulent combustion:

Combustion that results in a turbulent flame is mostly utilized for industrial applications as the turbulence helps in fuels and oxidizer mixing process.

7. Micro-combustion:

Micro combustion is combustions whose combustion processes take place in very small volumes. The high ratio of surface-to-volume increases loss of heat.

Fuels in Combustion

Substances or materials that undergo in combustion are known as fuels of combustion. The most general examples of this fuels are natural gases, kerosene, diesel, charcoal etc.

Liquid fuels:

Liquid fuels are combustible molecules that can be used to create mechanical energy and they also take the shape of their container. Combustion of liquid fuel happens in the gas phase. It is the fumes instead of fluid of liquid fuel which is flammable that is why a liquid catches fire only above a certain temperature.

Gaseous fuels:

Combustion of gaseous fuels takes place through any of these four types of burning: diffusion flame, premixed flame, autoignitive reaction or detonation. The types of burning are actually dependent upon the degree to which the fuel and oxidizer are mixed and also on the pressure exerted pre-heating.

Solid fuels:

Solid fuels are solid materials used as a fuel to produce energy and produce heat. Solid fuels include wood, charcoal, wheat, and corn, pellets made from wood and other grains. Humans have used solid fuel for many years for producing fire.