MASTER'S THESIS - SuSanA

4 Presentation of technologies for rural areas
4.3 Compilation and description of additional small and medium size
technology for rural areas
As the pre-selection of technologies of the consultant Martin Wafler was not done in a very transparent way
(criteria for selection not obvious or specific enough) and seems to miss other, already established low-cost
solutions, an additional presentation of technologies shall be given at this point. To give a complete
overview over the idea of sanitation systems, all parts of the system (user interface, collection,
(pre-)treatment and discharge/disposal/re-use) shall be considered as well.
4.3.1 User interface: Toilets with use of water
Toilet with the use of water can be pour-flush toilets and water-flush toilets, that shall be both shortly
presented.
4.3.1.1 Water-flush toilet
Water-flush toilets (or water closets) are the most common type of toilets in Europe, invented in England at
the end of the 18 th century and spreading over Europe in the following century (Londong 2008). Also the
rural Albanian population is using more and more water flush-toilets. Faeces, urine and most often toilet
paper gets flushed away through a drain pipe to for example a septic tank for collection or a centralised
sewer system that directes the wastewater to a treatment plant. Depending on the design of the flush,
between one or two liters up to twelve liters are flushed away by using the toilet. Water-flush toilets offer a
good hygiene and comfort, are easy to use and nearly no odour will occure. But they have the disadvantage
that a lot of water is used for transport means and that excreta will be diluted very strong. Therefore, a big
amount of wastewater has to be collected and treated.
4.3.1.2 Pour-flush (PF) sanitation technology
The pour-flush toilet is an improvement of the simple pit latrine where odours and insects are controlled by
a water seal between toilet bowl or slab and pit (leach pit). After toilet use, a very small amount of water up
to three litres is used for flushing. The water is poured in manually by the user. Every normal water-flush
toilet can get a pour-flush toilet if water supply breaks down (Spuhler and Wafler 2012). According to
(Ahmed and Rahman 2007), between five and ten liters of wastewater from excreta and the flush enter the
pit per person and day. Pour-flush toilets can be used in rural and urban areas.
The pour-flush toilet can be constructed in two different ways as a direct or an off-set pour-flush latrine (see
Figure 4.3 and Figure 4.4, p.32). The direct pit pour-flush latrine has a pit located directly below the toilet
bowl or squatting plate. The water seal makes it an improved version of the dry pit latrine. Off-set pit pourflush
latrines have a pit that is located somewhere else but not directly under the seat or squatting slab. Pit
and toilet are connected by a pipe with a diameter of 100 mm (DN 100). Therefore, the toilet can be
installed inside the house and no extra superstructure is needed. Toilets inside the house offer more
comfort and privacy. A special type of the off-set version is the alternating twin off-set pour-flush latrine.
The toilet is connected by a Y-junction with two leach pits, located a bit away from the toilet (off-set) with a
pipe of DN 100. The pits are used alternating. When one pit is filled up, excreta is directed into the second
pit and content of the first has time to decompose. After 18 - 24 months, the content shall be pathogen-free
and can be taken out. After emptying, the pit can be used again (Ahmed and Rahman 2007). The
advantages and disadvantages of that toilet type are compiled in Table 4.1 (p.32).
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