Conveying pipelines

Simple systems requiring a prime mover, a feeding device, a conveying pipeline and a cleaning or disengaging device (Marcus et al., 1990). 

Manual or automatic back-pressure unblocking of conveying pipelines. 

Diameter of conveying pipeline or particle to pipe diameter ratio. 

Flilbert, J. D., Multiple In-Line Splitting of Pneumatic Conveying Pipelines, J. Pipelines, 3 161-172 (1982)... 

D.J. Mason, P. Marjanovic, Re-visit to the fundamental definitions of fluid-solids flow properties in conveying pipelines, Proceedings of the 2nd International Conference on Pneumatic and Hydraulic Conveying Systems. UEF Conf. Davos, Switzerland, June 1999. 

In a horizontal conveying pipeline, motion of the particles is not always straight in the horizontal direction. Particles constantly fall down to the bottom of the pipe by... 

In a pneumatic conveying system, either positive or negative, materials are first fed into a conveying pipeline and then carried along the pipeline by the gas flow. After reaching the destination, particles are separated from the gas stream and collected in receiving bins. The... 

Adisadvantage of pneumatic conveying in general isthehigh power consumption and, with certain materials, the heavy abrasive wear of the conveying pipeline and of the material itself. With finely pulverized combustible materials there may moreover be explosion hazards under certain circumstances. Also, with certain materials there is a risk of blockage of the pipeline, especially at bends. 

Pneumatic conveying systems are basically quite simple and are ideally suited for the transport of powdered and granular materials in factory, site and plant situations. The system requirements are a source of compressed gas, usually air, a feed device, a conveying pipeline and a receiver to disengage the conveyed material and carrier gas. The system is totally enclosed, and if it is required, the system can operate entirely without moving parts coming into contact with the conveyed material. 

Twin blow tanks in parallel If two blow tanks are used, rather than one, a significant improvement in performance can be achieved. The ratio of the mean flow rate to the steady state material flow rate can be brought close to unity if two blow tanks in parallel are used. While one is being discharged into the conveying pipeline, the other can be de-pressurised, filled and pressurised, ready for discharging when the other one is empty. 

S.R. Kessel, The interaction between rotary valves and pneumatic conveying pipelines, PhD Thesis, Thames Polytechnic, U.K., 1986. 

For the purposes of design of a pneumatic conveying system, there is still no safe alternative to having some measurements of the flow characteristics of the bulk solid for which the system is to be designed, obtained from an actual pneumatic conveying pipeline. 

The pipeline was manufactured from carbon steel schedule 40 electrical-resistance-welded seamed pipe. This is virtually the industry-standard for a large proportion of pneumatic conveying pipelines. 50mm nominal bore was used as previous experience indicated this to be the smallest size from which scaling-up to substantially larger sizes gave acceptable accuracy. 

Bradley An Improved Method of Predicting Pressure Drop along Pneumatic Conveying Pipelines , Third Int Conf on Bulk Materials Storage, Handling and Transportation, Newcastle, NSW, 1989... 

Bradley, Pressure Drop caused by Bends in Pneumatic Conveying Pipelines - Effects of Bend Geometry and Fittings , Bulk Solids Handling vol 2 no 4, November 1990... 

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