Blue diversion: A new approach to sanitation in informal settlements

The sanitation concept Blue Diversion (www.bluediversiontoilet.com) was developed as a possible answer to the sanitation crisis in urban slums. It is based on two main elements: (1) diversion of urine, feces, and water at the source as the basis for efficient resource recovery, and (2) linking different scales (family toilets and semi-centralized resource recovery). Our objective was to develop an attractive grid-free (i.e. functioning without piped water, sewer, and electrical grid) dry urine-diverting toilet, which provides water (through recycling on-site) for flushing, personal hygiene (anal cleansing and menstrual hygiene), and hand washing. This service, including the entire sanitation value chain, should eventually be made available as a profitable business with total user fees of 5 ¢/p/d. The results presented in this paper are (1) a toilet design model, (2) the development of a new type of membrane bioreactor for treating flush and wash water, (3) main results of a geographic information system-based stochastic service model to link the family-scale toilet to a community-scale Resource Recovery Plant, and (4) a business model that yields maximum profit for the local community. We conclude that the approach is feasible, but challenging from a technical as well as an organizational point of view. A firm's competitive advantage originates increasingly from absorbing external knowledge. Absorbing external knowledge and the underlying learning processes are referred to as a company's absorptive capacity. In this article, we outline research trends on absorptive capacity. We apply a bibliometric analysis to describe the concept's historical development, define the intellectual core of the absorptive capacity concept, and discuss recent conceptualizations. Then, we identify two prominent streams in the absorptive capacity literature and provide a new approach on how to integrate them. Finally, we provide an outlook on possible themes in future research on absorptive capacity.