Dear Keith!
Welcome to the Discussion Forum. I have moved your post from the incoming mail section to this one. I hope you get some feedback. Have you reviewed the previous threads in this sub-category, in particular this one which has very detailed technical information (although for a colder climate):
forum.susana.org/241-composting-toilets-...aine-now-operational

All the best from a "fellow Australian" (well I'm German but am living in Brisbane),
Elisabeth

Having done some more detailed work on the plans my question is, could I get away with making the tank five blocks high instead of six? I am still aiming for a generous size tank to increase the times between servicing the system.

Comments invited on sketch plans for Clivus Multrum in Timor.
In particular I would appreciate comments on the dimension of the tank. I have decided that the tank being five blocks high should be sufficient. General comments on any aspects relating to the sketch plans would be appreciated. I planning to start building it by next week.
Please follow the link in the scribble above. Having never build a Clivus Multrum before, just telling me that there is not much wrong with the sketch plan provides a degree of reassurance. Much easier to make changes before building than afterwards.
Cheers Keith S

Are you hoping that the poo / pee / sawdust mix somehow moves itself down a shallow slope?

Geoff

Hi Geoff,
Yes, it was my expectation that it would move down the slope. Are you suggesting that I should increase the angle?
These are the very suggestions that I need, as I have never built or operated one of these.
Cheers Keith S

If indeed you are suggesting I increase the angle, than there are two ways to do this. Firstly stick with the original design of building the tank six blocks high and starting the ramp at the fourth block or if the tank is five blocks high, reduce the length of the ramp.
I suspect the first option is the better one.

Having just drawn some more lines on my plans, to start the ramp at the fifth block might even be a better idea. It certainly increases the angle and should help greatly in a downwards movement.
What is your option?

Hi Geoff and all,
Having has a few hours to think over how to increase to angle of the slope. I like to stick with the tank being five blocks high. With that in mind, I have come up with starting the ramp at block four and making it shorter. This will make for an angle of about 35 degrees. Does that look more promising?

Hi Keith,

I work with Ecoflo Wastewater - we are in Brisbane and we manufacture Clivus Multrum composting toilets. Your drawings are pretty close for sketches! Well done.

I have attached a paper setting out (see Appendices) some laboratory testing of the compost produced by various composting toilet systems - they certianly do produce compost and are quite effective at removing pathogens - albeit none of them tested for helminths.

The only rider is that composting toilets, like every sanitation system, need to be properly designed, properly installed and then properly maintained.

Happy to have a chat tomorrow or Friday and see if we can help you out?

Suggest you check out www.ecoflo-wash.org for a start.

We have an installation at Railaco - check out the case study on the site.

Joe

Hi Joe,
Thanks for your reply. I presume you agree that the increase of the angle of the slope should improve the operation of the unit?

People in Timor traditionally are bum washers. With this in mind and comments on the SuSanA.org site indicating that water use for washers can be between half and three litres of water per user, do you think this will inhibit to operation of the unit? Will three litres per person drown the system? It will have good drainage, as the floor slopes to one side into a decent size drain pipe.

The users of the system at Railico I presume are washers? The system copes OK with the extra water? Does it have a Urine diversion system?

You can contact me directly by email via the icon. If you do, I can ring via what’s app.
Cheers KS

Hi Keith,

The ClivusMultrum system is a waterless toilet and is not designed to handle any additional water beyond urine so I expect that the additional washing water will drown the system. It needs to compost and reach a sufficiently high temperature for thermophyllic effect to kill pathogens.

If the users are allowed to put bottom washing waster through the waterless ClivusMutrum system, I suspect that short term the additional water will just wash live pathogens into the environment and stop the composting process. Medium term the flow will likely sweep material down to clog the outlet pipe and turn the tank into a stinking mess.

The shape of the container as well as the slope is critical, which is why we only rotomould ClivusMultrum tanks. Unless you get several issues exactly right, the system is unlikely to perform well at pathogen removal.

What number of people is this system intended to service? How are you funding the construction?

Hi Joe,
Yes, I have concerns as well about bottom washing water, especially after finding out that some people use up to three litres of water. It has been customary for people to wash partly because of the unavailability and cost of toilet paper.

I will have a go in constructing a urine diversion system made from standard plumbing fittings. We will see if it works and how much it catches.

There are about 40 people onsite and it is next to the boys dorms (20 people) so I hope a two seater will cope with that. There are other toilets, a couple of squat ones and a WC toilet.

In Timor Leste there are cultural issues about the reuse of water, Grey as well as black. Traditionally people were reluctant to reuse any. Even rain water is rarely used. However people are happy to mix Grey and black and attempt to dispose of it by building holding tanks that leak (no bottom) and no leach drains. As long as the leaking is greater than the inflow, as is well. Many times this is not the case, tanks overflow and the toilets are locked up. People are reluctant to clean the tanks, as they are ‘dirty’, they rather build new tanks. So Timor is not short of toilet issues, hence my attempt to try something different. The toilets are based at an agricultural training centre that know and practices composting. To compost human waste plus carbon extras is something that they did not know about, but are willing to try.

We are working here as AVP volunteers under a program sponsored by DEFAT. In Timor nobody has a budget for anything and the college was going to approach some of their donors for funds to build the toilets. This was not going to happen in a hurry, so my wife and I decided to fund ourselves. The floors and footings are down and we start laying cement blocks in a few days. We might well have to include a supply of toilet paper in our budget.

I have made more detailed drawings to use as building plans. Please ask critical questions as this makes me reassess my presumptions.
Cheers