Clivus Multrum And Phoenix Composting Toilets

Clivus Multrum And Phoenix Composting Toilets

This week I will review two different composting toilet manufacturers with designs almost as unique as their names: Clivus Multrum and Phoenix.

Clivus Multrum Composting Toilet System.

Clivus Multrum” refers to both a certain type of toilet composting system and the manufacturer of that system. Clivus mean “incline” in Latin, while “Multrum” is a Swedish word meaning compost room, so Clivus Multrum means “inclining compost room.”

The first Clivus Multrum composting toilet system was built in 1939 in Sweden by Rikard Lindström, and this prototype was eventually patented in the 1960s. The Clivus Multrum composting toilet system involves a large remote tank connected by a slope to a toilet. The system requires a large accessible lower space beneath the toilet.

In the 1970s, Abby Rockefeller founded Clivus Multrum Inc. in the United States under a license from Lindström. With the current models using this system, a ventilation system will continuously pull air down, creating an odorless composting toilet system.  There also now is an automatic moistening system that will help keep the compost at the right moisture level for composting, and an automatic process to remove excess liquid from the composter as well.

Currently Clivus Multrum is marketing their composting systems towards more industrial and governmental purposes than towards home consumers.  They have a special “Trailhead” design aimed for use by national and state park services and portable models for use at golf courses and remote recreation areas. For more information, you can visit the Clivus Multrum website.

Phoenix Composting Toilet System

The Phoenix composting toilet system is manufactured by Advanced Composting Systems, LLC, based in Whitefish, Montana. The company has been manufacturing composting toilets for over 27 years, and also creates prefabricated buildings.

The Phoenix composting toilet system was developed in the 1980s by Glenn Nelson, who founded this company as a licensed manufacturer of Clivus Multrum toilets. Nelson used his experience with the Clivus Multrum composting system to build the Phoenix models, although they are unique in design.

Nelson sought to improve a few problems he saw with the Clivus Multrum system in the Phoenix design. One such issue was the slope of the composting tank found in the Clivus Multrum system, which caused concern about “fresher” composting materials possibly mixing with older materials awaiting harvest. Another issue Nelson pointed to with the Clivus Multrum original designs was how liquid pooled at the bottom of the sloped tank, turning the process from aerobic decomposition into anaerobic decomposition (for a discussion of the differences between these two forms, see “How Toilet Composting Works“).

Nelson created a toilet composting system which addressed both problems (Clivus Multrum representatives argue they have now also addressed both these problems with their own redesigns of their system). The Phoenix composting toilet is manufactured out of rotationally molded polyethylene, and unfortunately does not rely much on recycled plastic in its design. There are residential models available, although they are expensive when compared to other composting toilets on the market (the cheapest and smallest residential model starts around $3500). For more information visit the Phoenix Composting Toilet website.