Clivusmultrum M12 Composting Toilet System

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System Components

The recommendation is to have a single composting unit. Composting is assisted by worms, added 1 year after startup. The system is rated for 18,000 to 65,000 uses per year. The toilets need be above the composting unit. Toilets are either waterless or foam based and connect to the composting unit via a 14” diameter polyethylene shoot. The waterless toilets connect directly to the shoot. The foam flush toilets have a 4” hole at the bottom of the bowl with opens into the shoot. The foam flush toilets need to be “flushed” before and after each use. Ventilation occurs by drawing air down the shoot, through the composting unit, then up a vent stack. The system includes a compost Tea tank (500 gallons) and removal pump: Allows for the compost tea to be stored and distributed for land applications. Estimated Equipment Price for system: $10,000 for a system with two waterless toilets, or $15,000 for a system with two foam flush toilets. Individually sold, the waterless toilets are $425 per fixture and the foam flush toilets are $2700 per fixture. For the waterless fixture there are no consumables. For the foam flush, $185 per year should be budgeted for the foam producing soap. For either type, wood shavings should be amended into the compost, but these can be procured from local waste sources.

Toilet

Two toilet options exist; a waterless toilet or a foam flush which requires 0.2 L per flush plus a foaming agent. The foam flush requires and electrical connection. Non-potable water can be used.

Composter

Moistening system: 1 gal/day. Works on in house water supply so no additional pump is needed. Solenoid is 120 VAC, 50/60 Hz. . There is no heating system.

62Wx105Lx58.5H inches, 132 cubic feet

Fan: 115 V, 0.67 amp, 71 W, 60 Hz, 243 cfm. Runs continuously.

Liquid removal pump - pumps compost tea to storage. Operates ~4 min/day. - 115V AC, 5 Amp, 20.4 gpm. Compost tea can be used as fertilizer but needs to be disposed of on site.

Clivus Malturm, clivusmultrum.com, 800.425.4887, Lawrence, MA

Maintenance

Every 2-3 months, bulking material needs to be added. Pine shavings, which can be procured from most farm supply stores are recommended, but in general the bulking agent should be light and a wood which is easy to break down. Cedar should not be used since it is resistant to break down. At the same time that bulking material is added, the cone that develops at the base of the toilet needs to be knocked down. There is a “toe” to the compost tank which is intended to serve as a finishing area for compost. Compost is moved to the toe manually (the operator rakes it) and only needs to be removed about once every 5-7 years.