What is water cremation?

Why is it called cremation?

The name seems weird when water is involved, because we have become used to thinking of flames. But the original definition is ‘the chemical, mechanical, or thermal dissolution of remains to bone fragments.’  Perhaps, in time, the word ‘aquamation’ might take over as the popular way to describe the process. 

Exactly how significant is the advantage of Matthew Brown’s invention?

One of the most compelling reasons behind the growing interest in water cremation is its environmental benefits. Unlike traditional flame-based cremation, which releases a significant amount of carbon dioxide and other pollutants into the atmosphere, water cremation generates minimal air emissions. Most water cremation systems have about 1/20th of the carbon imprint of traditional flame systems.

And that’s just the first-generation system. Matthew Brown’s second-generation design slashes that by a further third.  It uses a lot less energy, a lot less water, and the process takes less than half the usual time, just 8 to 10 hours. See the diagram opposite. 

Less energy?  Yes, the first-generation systems used a lot more water and power, with high temperature, high pressure boilers (with the inherent safety risk).  The second-generation system operates at just 95 degrees Celsius.

Ashes and waste are both eco-friendly

Water cremation is about more than the bones. The neutralised liquid that comes from the process is also eco-friendly, enriching soil – farmers welcome it on their land. It can also be safely disposed of in waste-water, returning it to the water cycle - though some councils are still catching up with that in their regulations. See the diagram opposite.

Be aware that councils may be concerned about water cremation waste in their sewage systems. The cremation waste absorbs oxygen, so the council sewage system may have to work a little harder to increase the oxygen to the level they require. However, the volumes are very small so councils may not regard this as an issue.

What is alkaline hydrolysis?

For pet remains, it’s the process of using a mixture of water with a small amount of alkali to dissolve the soft tissue, turning it into a liquid. The alkali is usually potassium hydroxide. The water-alkali mixture is kept to 95 degrees Celsius.  

How does it work?  The process at a glance

It’s called alkaline hydrolysis. The body is placed in a specialized chamber, where it is submerged in a solution of water and alkali, usually potassium hydroxide. Then, the liquid is circulated and heated (below boiling), breaking down the tissue, mimicking and accelerating natural decomposition. That leaves the bones, which are turned into ashes and returned to the pet owner.