Slurry Pipelines

Mineral seal oil Mineral slurry pipelines Mineral spirits... 

Transportation. For short distances from the mine, transportation (qv) is by tmck or conveyor belt. Rail transportation is generally used for greater distances. Slurry pipelines (qv) ate being considered as an alternative. Rail transport over hundreds of kilometers results in loss of surface material in uncovered cats and a tendency to overheat in bottom-dumping tail cats owing to air infiltration around the cracks (31). Proper sealing and covets permit shipping over hundreds of kilometers. 

Dry soHds, such as as-rnined ore, emshed ore, and dried concentrates, are transported using tmeks, rail cars, ore passes, conveyor belts (see Conveying), or slurry pipelines (qv) as dictated by the logistics, distances involved, and capacity. Within the mill, conveyor belts are more common, but for fine particles, tailings, and coal, slurry transportation is more typical. 

Pipelines to transport soHds 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 hydrauHc conveying and capsule pipelines. When air or inert gas is used to move the soHds 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 soHd particles suspended in water or another inert Hquid. HydrauHc capsule pipelines transport soHd material within cylindrical containers, using water flow through the pipeline for propulsion. 

Slurry Pipelines. Finely divided soHds can be transported in pipelines as slurries, using water or another stable Hquid as the suspending medium. Flow characteristics of slurries in pipelines depend on the state of subdivision of the soHds and their distribution within the fluid system. 

Coal Slurry Pipelines. The only operating U.S. coal slurry pipeline is the 439-km Black Mesa Pipeline that has provided the 1500-MW Mohave power plant of Southern California Edison with coal from the Kayenta Mine in northern Arizona since 1970. It is a 457-mm dia system that aimuaHy deHvers - 4.5 x 10 t of coal, the plant s only fuel source, as a 48.5—50% slurry. Remote control of slurry and pipeline operations is achieved with a SCADA computer system. In 1992 coal deHvery cost from mine to power plant was calculated to be 0.010/tkm ( 0.015/t-mi) (28). 

The former Soviet Union constmcted a 262-km, 508-mm dia experimental coal slurry line between the Belovo open-pit coal mine in Siberia s Kuznets basin to an electric power plant at Novosibirsk, using technology developed by Snamprogetti. Testing began in late 1989 and tentative plans call for constmction of two much larger slurry pipelines, each 3000-km long, with capacity to move a total of 33 x 10 t/yr to industrialized areas near the Ural Mountains (27,33). 

Fiber Slurry Pipelines. Pipelines to carry suspensions of wood, paper, sludge, etc, have found commercial acceptance. Most of them are less than 15 km long but have diameters of up to 500 mm. These slurries are often concentrated and display viscous plastic properties, although particle sizes may vary special pumps are used. One such hydrotransport system carries a cellulose slurry by pipeline from the plant to a paper plant near Heidenau, Germany. The 250-mm dia pipeline carries 60 t/d over the 3-km distance to thickeners. In Sweden, a 3.7-km, 500-mm dia pipeline moves cellulose by... 

The usual means of transporting coal are railroad, barge, tmck, conveyer belt from mine to plant, and slurry pipelines (2,4) (see Transportation). In 1988 769 X 10 t of coal was transported to United States destinations of this, 57.5% was shipped by railroad, 16.0% by barge, 12.3% by tmck, and 14.2% by conveyer, slurry pipeline, and other methods (2). Electric utihties consumed 85.83% of the coal transported in the United States in 1988 (2). 

A 437 km slurry pipeline, 46 cm in diameter, was started in 1970 to move coal from Arizona to southern Nevada. The coal is cmshed and ground to the fineness needed for proper viscosity and settiing. About 18—20% is —325 mesh (<44 //m), 35—45% is —100 mesh (<149 //m), and 0—2% is + 14 (<1070 fim) mesh. The soflds content of the slurries has approached 70% using additives to stabilize the mixture. The slurry is dewatered with centrifuges before combustion of the coal. 

Coal slurry pipelines have been widely discussed, but few slurry pipelines have been built. In addition to the Black Mesa operation in Arizona, a 38-mile (61-km) pipeline was built by the Soviet Union, and a 108-mile (173-km) pipeline in Ohio was mothballed in 1963 after six years of operation. It is arguable to what extent the limited use of slurry pipelines is due to economics or to political opposition from rail car-... 

HlSAMtTSU, N Ise, T. and Takbishi, Y. Hydmtransport-7 (BHRA Fluid Engineering, Sendai. Japan) (Nov, 1980) B4 71, Blockage of slurry pipeline. 

You would like to determine the pressure drop in a slurry pipeline. To do this, you need to know the rheological properties of the slurry. To evaluate these properties, you test the slurry by pumping it through a 1 in. ID tube that is 10 ft long. You find that it takes a 5 psi pressure drop to produce a flow rate of 100 cm3/s in the tube and that a pressure drop of 10 psi results in a flow rate of 300cm3/s. What can you deduce about the rheological characteristics of the slurry from these data If it is assumed that the slurry can be adequately described by the power law model, what would be the values of the appropriate fluid properties (i.e., the flow index and consistency parameter) for the slurry ... 

A coal slurry pipeline is to be built to transport 45 million tons/yr of coal slurry a distance of 1500 mi. The slurry can be approximately described as Newtonian, with a viscosity of 35 cP and SG of 1.25. The pipeline is to be built from ANSI 600 commercial steel pipe, the pumps are 50% efficient, energy costs are 0.06/... 

Wasp EJ, JP Kenny, RL Gandhi. Solid-Liquid Flow in Slurry Pipeline Transportation. Clausthal, Germany Trans-Tech, 1977. 

Coal liquefaction, 6 765-766, 832-869 coprossing, 6 856-858 direct, 6 833-858 indirect, 6 858-867 use of steam in, 23 239-240 Coal mining, 6 744-745 Coal-oil coprocessing, 6 833, 856-857 Coal petrography, 6 706-709 Coal petrology, 6 706 Coals, ash properties of, 72 324t Coal slurry pipelines, 6 748 Coal tar... 

Mining and Ore processing Abrasion resistant linings for hoppers, chutes, cyclones, slurry pipelines, separators etc. Also bolt-in rubber wear plates for chutes and hoppers and conveyor rollers. Soft natural rubber for abrasion resistance. Hardness range 40 to 70°A... 

Coal-water slurry transport has been most thoroughly investigated and implemented. One of the earliest lines was 108 miles long, 10 in. dia, 50-60 wt % solids up to 14 mesh, at velocities of 4.5-5.25 ft/sec, with positive displacement pumps at 30-mile intervals. The longest line in the United States is 273 miles, 18 in. dia and handles 4.8-6.0 million tons/yr of coal it is described in detail by Jacques and Montfort (1977). Other slurry pipeline literature is by Wasp, Thompson, and Snoek (1971), Bain and Bonnington (1970), Ewing (1978), and Zandi (1971). 

E. Jacques and J.G. Montfort, Coal transportation by slurry pipeline, in Considine (Ed.), Energy Technology Handbook, McGraw-Hill, New York, 1977, pp. 1.178-1.187. 

E.J. Wasp, J.P. Kenny, and R.L. Gandhi, Solid-Liquid Plow in Slurry Pipeline Transportation, Trans. Tech. Publ., 1977, Gulf, Houston, 1979. 

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