Compost Juice Head Still

A still is a device that selectively heats a liquid mixture and then cools and condenses the resulting vapor to separate and remove it.

Urban composting systems usually result in a separation of concentrated liquids from solids as they break down organic matter. This includes bacterial systems like Bokashi and even just a simple anaerobic bucket.

Proposed here is a device to utilize even more effectively the waste products to extract pure drinking water.The Compost head juice still uses the waste liquid to concentrate the waste juice products even more and extracts useful water from it. It uses a system similar to a basic solar wick or Transpiration bag to collect condensed evaporate through gravity.

The main structure uses solar and body generated heat to slowly vaporize water from the compost juice and allow it to condense and drip down into a collecting vessel from where it can be easily removed.

The end result leaves behind salts, metals and impurities. The solar process also helps with eliminating microbiological organisms and other contaminates through UV-A sterilization.

Ideal capacity for liquid surface UV-A penetration is around the 2-3 liter capacity.

The attractive rounded shape enhances the heat and light transfer and reflection and increases and optimizes available condensation surface.  Materials for the upper surface structure should be highly transparent if possible to enhance solar sterilization of the liquids. Ideally this should be printed in PET or a material that allows UV-A light to pass through it.

The lower contact ring area that has contact with the head should be a more flexible material for comfort and better fit and possibly impregnated with a metallic compound for better heat transference from the body.

There is a simple in/out plug and drain system for adding juice into the top and removing condensed material from the base.

A generic plug in tube and mouth piece attachment can be easily obtained from any hardware or camping supplies store.

This system could also be used for other inputs such as seawater.

Possible enhancements:

A chin strap or bridle may be useful.

A basic fine mesh micro filter could be added to the internal extraction point for the mouth tube to remove possible accidental contamination with larger solids. Or added to the open internal area used to collect the condensate.

A small solar powered heating coil unit could be designed and added to the side walls during printing for cooler climates.

More complex internal surface fins could be added to the internal condensation drip surface area to help collect more vapor.


The results of a simple very quick and entertaining design exercise conducted at a March 2016 additivism workshop run at the Auckland University COLAB in NZ.

An STL file is available if you would like to try 3D printing one for yourself.