Granular materials - pipe - for hydraulic transport flow

Scientific field of mechanical process engineering deals with the flow of solid - liquid mixtures in pipes, called as hydraulic transport. In the construction industry the two most important applications are the underwater hydraulic sand and gravel mining and the pipe transport of the mixed concrete into the place of usage. In Hungary the longest slurry pipeline is situated in the slag - fly ash deposition system of the Matra Power Plant. Common feature of all the mentioned three applications, that the solid phase is composed by really fine and coarse particles as well. There are many hundreds km long slurry pipelines in the world. Of course, flowing suspensions and slurries in pipes can be found in many other industries, for example in mineral processing plants with wet technologies. This paper summarizes results achieved at the Institute of Raw Materials Preparation and Environmental Processing of the University of Miskolc during the last 20 years. Perhaps the most important result was the so called fine suspension - coarse mixture flow model. The model is a hydraulic transport design method based on physical material testing and pilot scale hydraulic transport experiments. Our partner, the EGI Ltd. has designed many fly ash handling systems based on the model and our material testing. Established installations are: Jacksonville Power Plant - USA, Craiova 2, Isalnita, Rovinari, Turceni Power Plants - Romania, Matra Power Plant, etc...