Estimated costs of implementation of membrane processes for on-site greywater recycling

摘要

Greywater reuse inside buildings is a possible way to preserve water resources and face up to waternscarcity. This study is focused on a technical-economic analysis of greywater treatment by a directnnanofiltration (NF) process or by a submerged membrane bioreactor (SMBR) for on-site recycling. Thenaim of this paper is to analyse the cost of recycled water for two different configurations (50 and 500ninhabitants) in order to demonstrate the relevance of the implementation of membrane processesnfor greywater recycling, depending on the production capacity of the equipment and the price ofndrinking water. The first step was to define a method to access the description of the cost ofnproducing recycled water. The direct costs were defined as a sum of fixed costs due to equipment,nmaintenance and depreciation, and variable costs generated by chemical products and electricitynconsumptions. They were estimated from an experimental approach and from data found innliterature, enabling operating conditions for greywater recycling to be determined. The cost ofntreated water by a SMBR unit with a processing capacity of 500 persons is close to 4.40 € mu00013n, whilenthe cost is 4.81 € mu00013nwith a NF process running in the same conditions. These costs are similar tonthe price of drinking water in some European countries.