An innovative greywater treatment system for urban areas ... - SuSanA

To get an overview of chronological sequence of water use, the typical water consumption
pattern in a hotel building over one day is shown in Figure 3. In a hotel in Jordan which is
equipped with a greywater treatment plant, it was monitored on 6 April 2010. It can be
characterised by two peaks of fresh water consumption/greywater production in the morning
and in the evening. It is obvious that the demand of water for toilet flushing can be provided
easily by volume of recycled greywater, furthermore there is still a huge potential for
additional use of service water, e.g. for irrigation or cleaning purposes (Rothenberger et al.,
2011).
Figure 3: Water consumption pattern for freshwater (blue), greywater (grey) and service water
(green) over one day, in a Jordanian hotel; (Rothenberger et al., 2011)
To characterise the greywater stream, the volumes and ingredients in comparison to urine
and faeces can be identified in the following illustration (Figure 4). In the first row of the
diagram the volumes of different wastewater streams are segmented in greywater (grey),
urine (yellow) and faeces (brown). The second row shows nutrient ingredients of the
fractions, including nitrogen (N), phosphorous (P) and potassium (K). The organic matter is
presented in the last row by amount of chemical oxygen demand (COD) in different sewage
water shares. Greywater constitutes a high volume and comprises a low level of nutrients
compared with excreta. All other partial sewage flows require a greater effort of recycling
preparation, therefore greywater is very well suited for the treatment and reuse. Another
advantage is the high volume in comparison to the other wastewater flows (Lange &
Otterpohl, 2000).
Figure 4: Sewage ingredients of greywater (grey), urine (yellow) and faeces (brown); (Lange &
Otterpohl, 2000)
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