Assessment of the quality of faecal sludge-based fuel briquettes (Tanzania)

This research aimed at assessing the effects of binding materials on the quality in terms of physical, combustion and emissions properties of faecal sludge (FS)- derived briquettes and their practical applicability and acceptability. Sunflower cake binder had the highest calorific value of 16.2 MJ/kg when compared to other binders used. Similarly, sunflower cake bond briquettes had the highest calorific value of 10.8 MJ/kg than other briquettes samples. Drying rates was higher for waste paper bond briquettes which was observed to be within 6 days from production while, the density of FS briquette was higher in banana peels bond briquettes having the density of 0.99±0.062 g/cm3. All briquette samples had carbon monoxide ranging from 871-3,612 ppm. These carbon monoxide results exceed the recommended level of 200 ppm, while nitrogen oxides results were within the recommended standard of 293 ppm. Results from questionnaire showed that FS briquette is relatively new to most of the respondents with 47% of the respondents not aware about the briquettes while 40% are aware but never used briquettes. The study recommends that, to get a good quality briquette made from faecal sludge a sunflower cake binder can be used. This is because as it has proved to have a higher heating value of 10.8 MJ/Kg compared to other binders, but also faecal sludge briquettes should be used in a ventilated or open environment in order to oxidize the higher level of carbon monoxide.