Slurry line

Homogeneous flow Solid concentration inside the tine is the same everywhere. This usually happens at high line velocity, or with fine solid particles. 

Heterogeneous flow There is vertical solid concentration gradient inside the line, less solids at top of the line, more solids at bottom of the line. This usually happens at reduced line velocity. 

Saltation flow There is a layer of moving solids at bottom of the line. Ibis flow region is due to further reduction in line velocity. 

Flow with stationary bed There is a layer of non-moving solid bed at the bottom of line. At this line velocity, solid particles will settle down at bottom ofline. 

A sluny line will be in one of these flow regions (I to 4 depends on its line velocity, 

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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). 

Sylvinite is removed from the ponds with scraper-loaders and hauled to a central pit. The salts are then transported to the refinery in a slurry line. KCl is separated from the NaCl by flotation. The flotation process is standard throughout the industry and is the same process used to separate KCl from impurities in a camaUite decomposition process explained later. An amine collector is used as one of the reagents. 

On small installations an elevated tank above the furnace would be used (refer to Figure 37). The savings from eliminating the pumps, valving, and slurry lines are offset by the additional cost of a structure to support the tank and a rotary feed valve. The tank is fitted with a screened overflow. A dewatering screw conveyor is used for feeding the furnace. 

Rupture of a slurry line in a FCC unit which ignited. 

To prevent large slurry particles from scratching wafers, filters can be used on the slurry lines. The drawbacks of filters in the slurry lines, however, are that (1) the slurry flow rate may decrease as the filter is being clogged and (2) the CMP polish rate can decrease as the filter approaches its end of life. 

As Example 5.1 shows, the velocities predicted by Eqs. (5.1) and (5.6) do not agree closely. Possibly an argument in favor of Eq. (5.6) is that it is proposed by the organization that designed the successful 18in., 273 mi Black Mesa coal slurry line. 

From statements in the literature, it appears that existing slurry lines were designed on the basis of some direct pilot plant studies. 

Grace W. (1980), Studies Colorado California Slurry Line. Coal Age, 85, No.4, p.45. 

Dissolved in naphtha, hydrogen chloride alone is not particularly corrosive the aluminum chloride slurry line and reactor feed line were of carbon steel. Carbon steel was also suitable for the hydrogen chloride stripper and absorber. 

Low solids content in product slurry. The cause of this is probably a restriction in the slurry pump suction line. Lumps can cause such restrictions and act as partial filters. When the problem occurs, it can usually be corrected by flushing the slurry line. 

Figure 5-12 displays the spectra of the Doppler signal for laminar flow at the recycle slurry line at the SRC-II pilot plant at various pump speeds (flow velocities). The characteristics of these spectra are (a) considerable energy concentration at low frequencies (the nature of this high-energy concentration... 

A coal slurry flow is a practical mixed-phase flow that requires close monitoring to ensure safe and efficient transport of the coal slurry. In addition to the flow rate measurement, detection of gas bubbles and settling of solids is equally important in coal slurry lines. In this section, we will describe a cross-correlation flowmeter that can reliably measure coal slurry flow rates over wide ranges of coal concentration and flow velocity. We will also illustrate how the flowmeter can detect settling of solids and recognize the presence of gas bubbles. Both laboratory and pilot plant flow tests are included. 

Raptis, A.C., Sheen, S. H., Roach, P. D., and Mech, J. F., Acoustic Noise Background and Sound Transmission Tests in a Slurry Line at the HYGAS Pilot Plant, Argonne National Laboratory Report, 1979 ANL-FE-49622-TM04. 

FIGU RE 4.16 (See color insert.) SRB-induced MIC manifested as perforations in a slurry line. (From Ringas C., The Southern African Institute of Mining and Metallurgy, 107, 381-384, July 2007. With permission.)... 

These valves (Fig. 6.8) operate automatically and may be treated as part of the pipeline. Regular inspection, however, is needed to prevent untimely failure the seats may crack or wear as may the flap and flap pin or ball or lifting seat. The latter two types can only be used in vertical lines but the flap type will operate in horizontal as well as vertical lines. It is difflcult to ensure a tight closure of these valves in slurry lines as there is a limit to the pressure that is applied to the flap or ball and even small amounts of solids on the seat will prevent a tight shut-off. 

As for slurry lines, the line routes should be reviewed at plant layout to minimize the route length and the number of bends. 

In the case of slurry lines, the requirements outlined in Chapter 15 must be observed. 

The transitional velocity Vi is obviously not used for the operation of slurry lines. It may be of interest in lab research, instrumentation, and monitor of start-up. 

It is very important to avoid blocking slurry lines. The profile of the pipeline must not include any steep gradients in excess of the critical slope. Slurry pipelines should be... 

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