Are you an EPFL student looking for a semester project?
Work with us on data science and visualisation projects, and deploy your project as an app on top of Graph Search.
Concept
Ash
Summary
Ash or ashes are the solid remnants of fires. Specifically, ash refers to all non-aqueous, non-gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash is the non-gaseous, non-liquid residue after complete combustion.
Ashes as the end product of incomplete combustion are mostly mineral, but usually still contain an amount of combustible organic or other oxidizable residues. The best-known type of ash is wood ash, as a product of wood combustion in campfires, fireplaces, etc. The darker the wood ashes, the higher the content of remaining charcoal from incomplete combustion. The ashes are of different types. Some ashes contain natural compounds that make soil fertile. Others have chemical compounds that can be toxic but may break up in soil from chemical changes and microorganism activity.
Like soap, ash is also a disinfecting agent (alkaline). The World Health Organization recommends ash or sand as alternative when soap is not available.
Ash occurs naturally from any fire that burns vegetation, and may disperse in the soil to fertilise it, or clump under it for long enough to carbonise into coal.
Wood ash
Products of coal combustion
Bottom ash
Fly ash
Cigarette or cigar ash
Incinerator bottom ash, a form of ash produced in incinerators
Volcanic ash, ash that consists of fragmented glass, rock, and minerals that appears during an eruption.
Cremation ashes, also called cremated remains or "cremains," are the bodily remains left from cremation. They often take the form of a grey powder resembling coarse sand. While often referred to as ashes, the remains primarily consist of powdered bone fragments due to the cremation process, which eliminates the body's organic materials. People often store these ashes in containers like urns, although they are also sometimes buried or scattered in specific locations.
Official source
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related courses (1)
ENV-304: Treatment and valorization of water and waste
Les systèmes eaux et déchets en Suisse: du traitement end-of-pipe à la fermeture des cycles. Principes de l'adduction, de l'évacuation et du traitement des eaux. Bases du dimensionnement des ouvrages,
Related lectures (7)
Material Flow Analysis: Modeling and Visualization
Introduces intermediate MFA project presentations, STAN and UMBERTO software, material stocks, building typologies, and urban mining flows.
Waste Incineration and Recovery
Explores waste incineration processes, energy recovery, emissions impact, and waste residues management.
Thermal Waste Treatment: Incineration Process
Explores the incineration process for thermal waste treatment and energy recovery.
Related publications (12)
Related concepts (6)
Pyrolysis
The pyrolysis (or devolatilization) process is the thermal decomposition of materials at elevated temperatures, often in an inert atmosphere. Temperature can be understood as thermal vibration. At high temperatures, excessive vibration causes long chain molecules to break into smaller molecules. The word is coined from the Greek-derived elements pyro "fire", "heat", "fever" and lysis "separating". Pyrolysis is most commonly used in the treatment of organic materials. It is one of the processes involved in charring wood.
Smoke
Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product of fires (including stoves, candles, internal combustion engines, oil lamps, and fireplaces), but may also be used for pest control (fumigation), communication (smoke signals), defensive and offensive capabilities in the military (smoke screen), cooking, or smoking (tobacco, cannabis, etc.
Charcoal
Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, called charcoal burning, often by forming a charcoal kiln, the heat is supplied by burning part of the starting material itself, with a limited supply of oxygen. The material can also be heated in a closed retort. Modern "charcoal" briquettes used for outdoor cooking may contain many other additives, e.