Comparison between treatment of kitchen-sink wastewater and a mixture of kitchen-sink and washing-machine wastewaters

• Published in: Environmental technology 2009-01, Vol.30 (1), p.111-117
• Main Authors: Huelgas, A., Nakajima, M., Nagata, H., Funamizu, N.
• Format: Article
• Language: English
• Subjects: Applied sciences; Biological and medical sciences; Bioreactors; Biotechnology; Chemical engineering; Conservation of Natural Resources; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General purification processes; higher-load grey water; linear alkylbenzene sulfonate (LAS); membrane bioreactor; Membranes, Artificial; Methods. Procedures. Technologies; Others; Pollution; Reactors; Various methods and equipments; Waste Disposal, Fluid - methods; Wastewaters; Water treatment and pollution
• ISSN: 0959-3330; 1479-487X
• DOI: 10.1080/09593330802445549

In this paper, a submerged membrane bioreactor was used to treat 'higher-load' grey water: a) kitchen-sink wastewater only, and b) a mixture of kitchen-sink wastewater and washing-machine wastewater. For each type of wastewater, three systems operated at different hydraulic retention times (HRTs) were investigated. In the mixture of kitchen-sink wastewater and washing-machine wastewater, the reactor with a short HRT of four hours was stopped due to foaming. It has been observed that for both types of wastewater, an HRT of eight hours or longer can be used for the treatment. However, it has been observed that a higher COD in the permeate of the mixture can be obtained compared with that of the kitchen-sink wastewater only. This indicated that washing-machine wastewater has some component that is not easily biodegradable. The total linear akylbenzene sulfonate (LAS) removal was > 99% even at a concentration of 10-23 mg l −1 .