Well, first of all you must ...
Published by Martin Regelsberger, Owner at Technisches Buero Regelsberger
Well, first of all you must be aware that few countries promote greywater reuse. That is mainly due to economic reasons linked to water utilities, which want to sell their water. Whether greywater reuse is cost effective is mainly a question of your water tariff and the cost for the treatment, which can be fairly cheap. In cases of water scarcity, availability of water may be more important than cost. Greywater certainly is a very reliable source of water.
Among the few that do promote greywater reuse Cyprus is quite prominent.
As for laundry, I don't know any place where it is actively promoted, but do know a few cases in Germany where treated greywater is used for laundry. There may be more cases in practice than I know of. It is certainly no problem to do it. I don't know any in Austria, where I am living, which may be due to water abundance here. Greywater can be treated to very good quality without particular problems.
A few technologies have proven particularly efficient. One is the use of multi-stage floating fixed bed reactors, with small foam cubes as supports for microorganisms. The retention time is roughly one day. You can operate the system as a sequence of SBR reactors.
Another possibility is a treatment wetland. Both vertical and horizontal wetlands have been used successfully. Dimensioning will depend on your climate. In Morocco we successfully applied up to 600 mm/d on a vertical bed. In colder climates a nice alternative is to have your wetland indoors, where it is not subjected to the cold outside temperatures in winter.
RBCs of any shape have also been successfully used for greywater treatment.
In any case you'll have to provide for a good removal of rough solids (including hair) at the entry and it is advisable to have a UV lamp at the end. Unfortunately membranes have not shown satisfying results with greywater so far.
Good luck and don't hesitate to come back with more detailed questions if needed.
Regards, Martin
PS: to reduce water demand avoiding conventional flushing cisterns is certainly another good means. In public places waterless urinals are easy to install and save a lot of water. In households toilet developments like blue diversion (http://www.bluediversiontoilet.com/) can offer an interesting solution. Research in this direction, which also allows the reuse of nutrients, is highly needed.
Among the few that do promote greywater reuse Cyprus is quite prominent.
As for laundry, I don't know any place where it is actively promoted, but do know a few cases in Germany where treated greywater is used for laundry. There may be more cases in practice than I know of. It is certainly no problem to do it. I don't know any in Austria, where I am living, which may be due to water abundance here. Greywater can be treated to very good quality without particular problems.
A few technologies have proven particularly efficient. One is the use of multi-stage floating fixed bed reactors, with small foam cubes as supports for microorganisms. The retention time is roughly one day. You can operate the system as a sequence of SBR reactors.
Another possibility is a treatment wetland. Both vertical and horizontal wetlands have been used successfully. Dimensioning will depend on your climate. In Morocco we successfully applied up to 600 mm/d on a vertical bed. In colder climates a nice alternative is to have your wetland indoors, where it is not subjected to the cold outside temperatures in winter.
RBCs of any shape have also been successfully used for greywater treatment.
In any case you'll have to provide for a good removal of rough solids (including hair) at the entry and it is advisable to have a UV lamp at the end. Unfortunately membranes have not shown satisfying results with greywater so far.
Good luck and don't hesitate to come back with more detailed questions if needed.
Regards, Martin
PS: to reduce water demand avoiding conventional flushing cisterns is certainly another good means. In public places waterless urinals are easy to install and save a lot of water. In households toilet developments like blue diversion (http://www.bluediversiontoilet.com/) can offer an interesting solution. Research in this direction, which also allows the reuse of nutrients, is highly needed.