Hydraulic conveying

The Chemistry and Technology of Coal, James G. Speight Pneumatic and Hydraulic Conveying of Solids, O. A. Williams Catalyst Manufacture Laboratory and Commercial Preparations, Alvin B. Stiles... 

Figure 5.9. Hydraulic gradient-velocity curves tor 200 fim sand in 25 mm diameter hydraulic conveying line...

It is seen that the models put forward do not adequately explain the behaviour of hydraulic conveying systems and they poorly correlate the results of different workers. 

Abbott, M. Ph.D. Thesis, University of London (1955). The Hydraulic Conveying of Solids in Pipe Lines. 

Pneumatic and hydraulic conveying, in which the solid particles are transported along a pipeline in suspension in a fluid, are discussed in Volume 1, Chapter 5, and in a book by Mills (2003) see also Mills et al. (2004). 

In a similar way, a high liquid velocity will cause hydraulic conveying in a liquid-solid fluidized bed. 

Solid particles hydraulically conveyed in a vertical pipe have a mean velocity which is less than the mean velocity of the liquid. This is because of the tendency of the particles to settle. The volume fraction a in equation 9.42 is the delivered concentration. This is less than the volume fraction in the vertical pipe. 

Solid particles hydraulically conveyed in a vertical pipe are subjected to various forces which cause them to rotate and move inwards towards the axis of the pipe. The effect is most pronounced with large velocity gradients. 

Newitt, D.M., Richardson, J.F. and Gliddon, B.J., Hydraulic conveying of solids in vertical pipes, Transactions of the Institution of Chemical Engineers, 39, pp. 93-100 (1961). 

Details of the current restructuring of this Chemical Engineering Series, coinciding with the publication of the Fourth Edition of Volumes 1 and 2 and to be followed by new editions of the other volumes, have been set out in the Preface to the Fourth Edition of Volume 1. The revision involves the inclusion in Volume 1 of material on non-Newtonian flow (previously in Volume 3) and the transference from Volume 2 to Volume 1 of Pneumatic and Hydraulic Conveying and Liquid Mixing. In addition, Volume 6, written by Mr. R. K. Sinnott, which first appeared in 1983, nearly thirty years after the first volumes, acquires some of the design-orientated material from Volume 2, particularly that related to the hydraulics of packed and plate columns. 

O.A. Williams, Pneumatic and Hydraulic Conveying of Solids, Dekker, New York, 1983. 

Pipelines to transport solids are called freight pipelines, of which three different types exist pneumatic pipelines, the use of which is known as pneumotransport or pneumatic conveying slurry pipelines, which may also be called hydrotransport or hydraulic conveying and capsule pipelines. When air or inert gas is used to move the solids in the pipeline, the system is called a pneumatic pipeline and often involves a wheeled vehicle inside the pipeline, propelled by air moving through the pipe (25). Slurry pipelines involve the transport of solid particles suspended in water or another inert liquid. Hydraulic capsule pipelines transport solid material within cylindrical containers, using water flow through the pipeline for propulsion. 

P. Marjanovic, A comparison between pneumatic and hydraulic conveying, Proceedings of the 19th Yugoslav Congress of Theoretical and Applied Mechanics, Ohrid, Yugoslavia, 1990, pp. 61-66 (in Serbian). 

P. Marjanovic, D.J. Mason, T. Mooney, The Performance of a pneumatic conveying system which incorporates an inclined pipeline section, Proceedings of the 1st International Conference on Pneumatic and Hydraulic Conveying Systems, Florida, USA, 1996. 

Washington, D.C. Bureau of Mines Information Circular, U.S. Deptartment of Interior. Williams, O. A. (1983). Pneumatic and Hydraulic Conveying of Solids. New York Marcel Dekker. 

Yin, W. L., and Wang, H. X., Quantification of swirling flow in hydraulic conveying from resistance tomography images, Instrumentation and Measurement Technology Conference (Conference Proceedings, Vail, CO, USA), 20-22 May (2003). 

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