Intro: Stand Alone Hand Washing Unit for Dry Toilets
This project was initially created with 2 other colleagues Pierre and Victoria for an innovation contest in partnership between our company foundation and Red Cross. the request was to find a low cost, with low water consumption, easy to transport, robust solution to allow to wash hands in countries in crisis situations like after an earthquake. Washing hands is key to avoid dramatic health situation, and there was a need to improve the existing system which was not portable enough.
The project is a team project, with ideas from all of us, but we also had contributions depending on our skills, the nice presentation was done by Victoria which is an industrial designer, whereas Pierre made the stability calcultation and the compliance matrix, and I was more on proof of concept and prototype manufacturing.
We found a nice name for the project: TIPITANK. It comprises a wood tripod in the shape of a tipi, a water tank made with a 'Bag in box' (a wineskin made of plastic film, which contains wine, and which collapses when emptied), a bag to sustain the bag (!), some PVC pipes, a rubber manual pump (usually used to feed gasoline to start an engine like on boats, it comprises non-return valves), a spraying nozzle from a hand sprayer, and finally a foldable bucket to collect dirty water. When pressing the pump with the foot, you pump water from the bag, and spray water.
It is very clean, since you operate with the foot and don't touch anything, there is no tap. Once filled the water is not polluted since no air enters into the bag. The system is autonomous, and doesn't need any energy source other than the human action. And very little water is used, so it can last for a lot of washing actions before needing to be refilled. The system is very rustic and could even be locally produced. It is fully foldable and is therefore easy to transport. We didn't won the contest, but I nevertheless think it is worth publishing and sharing.
Having a prototype available, I recycled it into a hands washing unit close to the dry toilets which are in my garden. As you can easily recognize it from the name, there is no water in dry toilets. But nevertheless, you still need to wash your hands after using the toilets. I adapted the Tipitank principle to bring a solution for that problem. And I am using it for more than one year, and it is very usefull and efficient.
I propose this project to the contest Water, if you like it, please Vote!
Step 1: Transposition to Backyard Dry Toilets Washing Hand Solution
The Tipitank demonstrator was using two bags, I canceled one connection.
I used a Bag in a box which has no refilling port, since it is supposed to be used once and thrown away after use. It is therefore necessary to fill the bag through the tap. With some patience it is not so difficult. the pipe is then just forced introduced in the tap, and the tap is maintained open with a tyrap.
I didn't need the tripod since I just hanged the bag to the compost pallet wall and the pipe and the nozzle is just going through the pallet wood.
The bag must be below the nozzle so that there is no leakage when not used.
I didn't need either the bucket since the dirty water is just falling in the compost.
Since the ground is a bit soft, I put a stone below the rubber pump.
I hanged a soap directly above the nozzle, and that's done, it is ready to use. Children like it a lot! I used it for more than one year already and it works very well.