Reuse of faeces and urine from ecological sanitation
Practical Action
on top, in a similar vein as an ‘aborloo’. If use is not possible at all the faeces should be
disposed of safely.
Urine
Urine carries the majority of nutrients and few pathogens. This is one of the reasons for
employing urine diversion methods as the nutrients are preserved. This section will run
through the main methods of urine treatment, the methods for application and other practical
recommendations.
Pathogens in urine
Pathogen content in urine is very low, the majority being present due to cross contamination
with faeces. Therefore it is of primary concern not to allow faeces into diverted urine.
Treatment
Due to the lower pathogen content the treatment methods of urine are much simpler than for
faeces. Storage remains the main methodology. In all cases it is preferable that urine is not
diluted, as undiluted urine increases die-off of pathogens and prevents mosquitoes breeding.
Treatment options are outlined below.
Storage – This has long been the accepted method of treatment, the level of pathogen die-off
will vary with additional factors, most notably temperature. At a household level it is generally
acceptable for the urine to be applied to land without storage as long as the crop is for the
households own consumption and a month passes between fertilising and harvesting. This is
advised because person-to-person transmission of disease within the household is of greater
probability than transmission of disease through contaminated crops. Table 3 shows the
recommended storage times at different ambient temperatures.
Table 3: Recommended storage time for urine based on ambient temperature
[Adapted from: Schönning and Stenström, 2004]
Storage temperature Storage time Possible pathogens
Recommended crops a
(ºC) present after storage
4
≥ 1 month
Viruses, protozoa
Food and fodder crops to
be processed
4
≥ 6 months
Viruses
Food crops to be
processed; fodder cropsb
20
≥ 1 month
Viruses
Food crops to be
processed; fodder cropsb
20
≥ 6 months
Probably none
All cropsc
a – The recommended crop is for larger systems where crops will be consumed by individuals
other than members of the household where the urine was collected.
b – Not grasslands for production of fodder.
c – For food crops consumed raw leave one month between fertilising and harvesting and work
the urine into the ground where the edible part of the plant is above the soil surface.
Figure 2: Options for re-use of urine from ecosan.
[Illustrator: Hans Mårtensson; Source: Esrey et al, 1998]
Other Treatments – Storage is
the only treatment method
that has been widely practiced
to date. Evaporation of urine
to concentrate nutrients has
been attempted but is not yet
efficient enough to practice.
Increasing the temperature
and/or pH of the urine will
speed up inactivation further.
Increasing temperatures above
20ºC have not yet been
practiced (Schönning and
Stenström, 2004).
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