Alkaline Hydrolysis

What is Alkaline Hydrolysis and how is it used? Here is a definition of this funeral term which also may be referred to as aquamation or liquid cremation.

Definition of Alkaline Hydrolysis, also known as Aquamation


Alkaline hydrolysis is a water-based process used for the disposal of human and animal remains. Similar to flame cremation, where a corpse is reduced to ashes in a furnace, Alkaline hydrolysis reduces bodies into primarily bone fragments. However, alkaline hydrolysis uses water, heat, and alkalinity instead of flames. The same decomposition process occurs naturally when a body is buried in the ground, except the alkaline hydrolysis process accelerates decomposition.

The process of alkaline hydrolysis -- sometimes called aquamation or liquid cremation -- starts with the placement of a body in a stainless steel vessel. The vessel is filled with water and potassium hydroxide (alkali), which is also referred to as lye, an odorless, off-white flaky, or lumpy solid.

The quantity of alkali used depends on body characteristics such as weight and gender, but the ratio for the solution is approximately 95 per cent water and five percent alkali. The vessel's contents are then subjected to high temperatures (200 to 320 F / 93 to 160 C) and agitation to prevent boiling and to promote breakdown of organic material. During the process, fats, proteins, minerals, and carbohydrates from the remains are reduced to basic organic components (i.e., fats get reduced to salts). They become dissolved into the water.
The process results in a green-brown liquid and bone remains. Next, the liquid is released from the vessel, and the remains and equipment are rinsed with fresh water. The leftover liquid is disposed of into a sewer or wastewater treatment system. Finally, the bone material gets processed into a powder, placed in an urn, and returned to the family or next of kin.

The scientific name for the process is alkaline hydrolysis. However, it is also referred to using many different terms, including aquamation, green cremation, cremation, water cremation, liquid cremation, flameless cremation, chemical cremation, and resomation.

Some call alkaline hydrolysis a more “eco-friendly” option. This is because it does not produce direct emissions of harmful greenhouse gases or mercury. In addition, there is no burning of fossil fuels. The process uses less energy than flame cremation, all at a similar price point.