Composting Toilet Systems: Excel Marine

The Excel Marine is a system specifically designed by Sun-Mar for use in boats. It has all the features of a standard Excel plus a few additional ones to make it seaworthy. The Excel Marine can handle up to 4 people in full time use or up to 8 people on a part-time basis. The Excel Marine has a unique three chamber processing system including the patented Bio-drum. It is a stand alone single unit composting toilet with a high gloss white fibreglass casing. The Excel Marine is superior to competing self-contained products because it uses a rotating drum to mix and aerate the waste rather than a mixing bar or rake. The drum ensures optimum composting by providing the best composting conditions. The waste falls into the Bio-drum where it is mixed and composts for approximately 2-3 months. After this time some of the material is released into the finishing tray where it sits for a further month sealed from any fresh material to complete the composting process.

Like the standard Excel, the Excel Marine comes with a 220 Volt heater to improve the composting conditions. It also includes a 12 Volt heater for use when there is no 220 Volt power available. A 12 Volt fan with a filter is also included to remove odours via a 3” vent pipe. The fan filter consists of activated carbon and zeolite materials which “scrub” the air of fresh ammonia odours ensuring odour-free operation at deck level. The Excel Marine vent pipe comes out of the top of the system which allows the toilet to sit flush against the wall of the toilet room thus conserving space. Along with speeding up the composting process and removing odours, the fan and 220 Volt heater act to evaporate all of the liquid waste produced. However, when at sea (away from 220 Volt power) it may be necessary to connect the system to a small container or small holding tank to collect any liquid waste that fails to evaporate.

Due to possible violent motion at sea, the finishing drawer of the Excel Marine has been gasketed to ensure that no liquid can escape from the evaporating chamber. The air intakes have also been located higher up and ducted down to the evapourating chamber. Strong mounting brackets have also been fixed to the system to ensure that the toilet is firmly fixed to the floor and won’t tip over in rough conditions. A drum lock keeps the composting drum upright under all sea conditions.