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

Due to the complexities, involved in data acquisition, caused primarily by the companies
obligation to maintain the confidentiality of certain data, not all fields in the tables were
received and therefore information is not totally complete. Nevertheless, it provides an
overview of the wide range of applications of greywater MBR technology worldwide, there
are multi-storey dwellings, hotels, halls of residence, indoor swimming pools, shopping malls,
office buildings, assembly sets and so forth. As a result of consultation with German
companies in this study, many projects listed have been realised in Germany, but there are
still numerous international applications listed as well in the table.
Regarding the type of building where greywater treatment plants are installed, there is
prevalence of residential buildings. 18 of the 31 greywater treatment projects are installed in
buildings where persons stay overnight. These are buildings where in proportion to edifice
size high volumes of greywater are produced, because water from bath tubs and showers
accumulates additional to water from hand washing basins. In this case the balance of
greywater volume and process water demand can be accomplished very well (see section
2.1.2).
The treatment capacity of collected projects are very different, they vary between 250 l/d
for a recycling system for yachts (3 users) and 250.000 l/d for a housing development project
in Turkey for 3.500 single-family dwellings. Further big projects are a holiday resort in Jordan
with 80.000 l/d, Airport I in Turkey with 60.000 l/d and the police academy with 400 persons
in Mazar e Sharif/Afghanistan with 20.000 l/d.
The projects in office buildings are mainly small pilot plants to demonstrate the function of
the technology and as a role model for decentralised sewage treatment. The plants in
Berching, Eschborn and Ankara were built with this motive, to be a pioneer in this area.
Considering the reuse of purified water within the projects there is an obvious lead of the
application for toilet flushing (25 of 31 projects). An additional use of recycled greywater for
irrigation is common as well; in 7 applications a supplemental use for washing machines was
identified.
Based on a literature study there is another greywater treatment system called
“AquaCycle” developed by a German company called Hansgrohe AG / Pontos GmbH. It uses
a patented biological/mechanical “SmartClean” process without any membrane, based on
fluidised bed technology. The system has been tested with respect to safety and operation
by an accredited inspection authority, for treating shower and bath water as a closed system
in compliance with the hygienic/microbiological requirements of the EU directive RL
76/160/EWG (1975) and RL 2006/7/EG (2006) relating to bathing water quality (Pontos,
2010). The reason to mention this technology is that the system is constituted in a compact
size, similar to MBR treatment plants. Hence, the application areas of these plants are typical
scopes for membrane bioreactors as well. In Table 14, there are several international
greywater treatment plants using “AquaCycle” technology presented.
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