Composting Toilet: Part 2
Removal of all Old Hoses & Fittings
While it was a dirty and smelly job, I was glad to get rid of all the old discharge hoses, the siphon loop, and the y-valve. ( I had already removed the holding tank and installed the auxiliary diesel tank in its place.). Because of the confined space, it took about 3 hours to remove the marine toilet, all the old hoses, and fittings.
|It's hard to believe all the volume that is consumed by hoses and fitting used in a |
conventional marine toilet and this load didn't include the holding tank.
|In this photograph the old conventional marine toilet was removed and the new |
composting toilet had not yet been installed. It looks like a lot of space is available.
Preliminary Fit Up of Toilet
|This photograph shows the shelf extender in place before the toilet was mounted. |
After this photograph was taken I removed the shelf extender for varnishing.
Mounting the Toilet
With the shelf extender in place and the toilet sitting in position, I carefully marked the locations of the toilet supports on the liner shelf. I removed the toilet from the area and removed the support feet from the toilet, marked the mounting hole locations, and drilled them out per the instructions.
|Following the instructions exactly, I first marked the outside surfaces of the toilet's support |
feet while fastened to the toilet and before mounting. Then, I removed the toilet
and the feet and marked the hole locations.
The continuous movement of air is what makes a composting toilet work (particularly in humid environments). Air is drawn into the toilet through a screened opening, into the solid waste compartment, and then it flows out through the exhaust hose until it leaves the boat. The exhaust fan is located at the exit point from the boat. (I ordered 20 feet of air hose with the composting toilet since I was unsure how much length I would need--this turned out to be a smart move.)
|I fastened a 9-mesh stainless steel screen into the cut down cowl vent using two pop rivets. |
The screen is intended to prevent wasps and spiders from building nests in the cowl
vent and blocking the egress of air from the new toilet.
|The hose opening for the right angle exhaust mount actually faces aft and the exhaust |
hose makes a generous U-turn just prior to the exhaust. The fan is very
quiet--you can barely tell it is running.
Adding the Composting Medium
The medium to be added in the solid container comes in the form of a 650 gram brick (about the size and color of an actual brick). We put the coco coir brick in a bucket with 2 quarts of fresh water and kept breaking it up. We allowed it to sit overnight and, by the morning, it absorbed all the water and was ready to be put into the solids container.
|The coco coir brick and two quarts of water turned into about 3/4 of a bucket |
of composting medium, ready to be put into the solids container.
We are now a "zero discharge" boat and, not only environmentally responsible but, we also save money in holding tank pump out costs.
|The installation was completed within two weekends, with some additional work done |
in the evenings during the week. Note the holes from the old hoses on the lower
right side of this image--they will be addressed in our next blogpost.
|The cut down cowl vent is inconspicuous and works perfectly so far. I have some |
concerns about the possibility of a wave hitting the deck in rough seas, getting up
inside the cowl vent and shorting out the fan but we'll see how it goes.