Recycling

The term recycling commonly applies to recycling goods and consumer items. For the large scale recycling of water and air, see Water infrastructure and Life support articles.

A colony on Mars uses a number of materials to build everything they need for living. Mining or ISRU in the main way of adding materials to the settlement. Importation from Earth or other planets is another.

To reduce the need for extracting or importing materials Recycling can be used. Especially if the litter consists of only elements including just a few materials, and most easily if the pieces of litter are made from a single material. The concept requires special manufacturing that takes care to use pure single material if possible, or allows for easy disassembly.

Things made from single materials

Bottles from glass.
Boxes from plastics (e.g. polyethylene).
Tins from stainless steel.
Insulating foam from melted and expanded regolith.
Insulating foil, e.g. from polyethylene.

Things made from a material composition

The following things need more than one material, but the materials can be separated easily for recycling:

Electric cable from metal and plastics (e.g. polyethylene).
Insulating mat from mineral fibre and plastics casing (e.g. polyethylene).
Laminated safety glass.

Economics of Recycling

As the colony grows in size and population, the economics of the colony starts. Using free market it is easy to determine whether it costs more to mine material or to recycle it. Recycling may be a cheaper than mining in many cases. This is already obvious on Earth, where plastics, lead, aluminum and steel have higher and higher recycled content as the recycling systems develop.