Regain of activity on Filter pot project

Good news: after a few months of dicreased activity (mostly because the potters where out on their farms) and despite the big mistake they made on the the last batch of pots (mixes not been marked properly), the potters, under the direction of Pelegia Chamwali have been very busy producing prototypes.

We are currently experimenting 2 different mixes:
1) CLAY + rice husk
2) CLAY + sawdust

For each of them, I've asked a series of pots with different mix ratios, including:
RH / SD 1 : C 0.75
RH / SD 1 : C 1
RH / SD 1 : C 1.25
RH / SD 1 : C2.5

George our technical adviser is currently away for two weeks but we should be able to make 2 burnings when he comes back from his holidays. After this, we will test the different flow rates and proceed some fecal coliform tests to evaluate what is the best mix and how efficient the filter is.

Once this is done and provided we get some satisfying results, we will be able to focus more on detailed use and design as well as improvements of production techniques... The workshop space is working well and we're now glad we made a big reserve of clay.

2 of the potters in the workshop

Some of the new prototypes with sawdust-clay mix

Some prototypes with Rice husk -clay mix.

As you can see, the rice husk mix is getting fungus (white layer) very quickly: these pots are only one day old!! This shouldn't be a problem once we fire the pots, but assuming there is no difference in efficacity, we will probably choose to continue with sawdust for the following reasons:
- no fungus at fabrication stage
- sawdust is easier to sieve and finer (i.e. more likely to be a good filter)
- we get it for free from small local industries which otherwise have to transport + burn it!

Also you can see the top of the rice husk pots has not turned white. This is because we are using pure clay for the ringbeam, as we believe it will increase solidity. This is a clear advantage we have with manual fabrication.