6. CONCLUSIONS

-The process of jigging was tested in a laboratory-scale jig being operated in batch mode.

-The stratification of the material bed can be improved by a longer duration of the process and a higher stroke. The effects of both parameters are strongly connected with the applied type of oscillation.

-The separation is influenced positively if assymetrical oscillations will be applicable. An accelerated upward flow for an intensive loosening of the material bed and a retarded downward flow for a consolidation results in the best stratification.

-The material combinations of light material and concrete or brick as well as the combination of gypsum wallboard and concrete could be separated by jigging. The processing of the combination brick / concrete does not show the wanted results even at very effective process parameters.

-On the basis of the tests an empirical model was developed, that allows to calculate the achieved separation in dependence of parameters of the process and the material. Of course the model is valid only within the rage marked by the experiments.

-In future works a model on the basis of the Discreet Element Method shall be developed. Such a model has the advantage that it is more independent of experimental data. Nevertheless reliable predictions are possible if the process is correctly reproduced in the model.

-The experimental results will be incorporated in the development of an improved jig. The construction of a semitechnical-scale jig has started already.

ACKNOWLEDGEMENTS

The presented results come from a joint research project between the Bauhaus-University Weimar, the IFF-Weimar e.V. and the its Institut for technical documentation, training and consultation GmbH.

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