Preliminary experiments with spouted beds of binary mixtures of particles have shown that segregation according to size or density clearly occurs, with heavier particles going to the upper inside part of the annulus. Segregation tendency becomes less pronounced with increasing gas flow rate. During continuous operation, the concentration of coarse particles in the discharge stream was found to be initially lower than in the feed but it increased within a short time (10–50 min) to the feed concentration. However, the proportion of coarse particles in the bed solids (x) always remained higher than in the solids leaving the bed (y). A state of equilibrium was found to exist between these two concentrations, described by the following equation: y = xn The exponent n turned out to be a function of gas velocity and particle size of the individual components of the mixture, but, not of their proportions, nor of feed rate. An empirical correlation for n is proposed.

Rural areas are facing vulnerabilities and changes caused by negative social, economic and ecological externalities resulting from industrial agriculture systems. Locally embedded farms and bottom-linked approaches such as social cooperatives that act in the field of social agriculture are small, but valuable models to counteract these trends. This article is based on a case study conducted within the transdisciplinary research and development project Unlocking the Potential of Social Agriculture (UPAS), 2017–2020—financed by the Free University of Bolzano. The main focus of the case study is to determine the impact of social agriculture initiatives on social and healthcare systems, the natural environment and the communities in which they act. Data collection includes a literature review, observations and interviews carried out on 35 case studies of social agriculture initiatives, mainly located in Italy. The field research points out that actors in the sector of social agriculture predominantly aim to integrate disadvantaged people socially and in terms of their labor, base their production on organic methods, and that social agriculture has the potential to foster eco-social transformation and development of rural areas by the combination of social and ecological concerns. Thus, we use the term “eco-social” agriculture to describe these approaches. Furthermore, five components of eco-social agriculture have been defined, which, together, offer an ideal set of acting principles, namely: (1) the empowerment and integration of disadvantaged people, (2) the promotion of environmentally friendly agricultural practices, (3) the protection of nature, resources and cultural landscape, (4) support to the local community, and (5) education for sustainable development.

Bibliografische Information der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über http://dnb.d-nb.de abrufbar.

No abstract

No abstract