Hi, I have just been reading a recent paper about faecal reuse by Stefan Diener and partners in Uganda, Senegal and Ghana.

The paper is here: www.sciencedirect.com/science/article/pii/S0921344914000913

The paper lists various types of faecal reuse including fuel, feedstock for insects, biogas and soil conditioning. It also has a paragraph on the use in building materials.

It says:

Brick manufacturing is pervasive in Kampala, so the use of faecal sludge in building materials was pursued during interviews with brick manufacturers. However, there was a relatively negative perception among brick manufacturers with regard to this enduse. The main reasons given during interviews were concerns about consistent characteristics of faecal sludge, and the abundance of conventional raw materials negates the need for an alternative. This indicates that faecal sludge incorporation into building materials can be considered but would probably only be of interest in areas where raw materials are limited.

This seems rather unlikely (and undesirable) to me, is it a common practice anywhere that anyone is aware of?

I ought to add that using animal faeces in building construction is a common practice, including here in the UK in the past. I have never heard of anyone suggesting this is or should be a practice for human faeces, though.

Well, just to prove me wrong, I learn that there is a company in the UK which is experimenting with this - turning faecal waste into bricks.

Apparently the faecal waste is turned to ash, which is then used in the bricks. Probably not the kind of practice which would be applicable in a developing country, but maybe the idea is not as unlikely as it first sounded.

The company is here: www.encosltd.com/

One discussion I heard was that the fibre content is important if using waste 'unburnt' - when animal waste is used, it tends to be from herbivores, so as long as the 'source' population is vegetarian... !

Dear Joe,

I also don't see it as a very likely solution. What is your main problem with it, considering that bricks are baked at high temperature? Handling of the sludge mixed clay by the people who make the bricks?

By the way, is there anything in the paper regarding using dried sludge briquettes as fuel in the kilns?

Regards

Marijn

By the

Energy needed to bake bricks, fumes, dust etc. Possibly manual handling problems.

Yes, there is a section on "Dry sludge as fuel for combustion" although I'm not sure if this is the same as 'briquettes'.

It says that in Dakar "all interviewees were interested in the potential of faecal sludge as a fuel, but first wanted to see a demonstration to verify the feasibility."

In Kampala "45% of the interviewed companies were immediately willing to use faecal sludge if it met their requirements, 30% were dependent on verification of compatibility with current infrastructure, and 25% were undecided."