Tank sizes

The correlation for based on experimental data has been weU researched. The pioneering work was carried out in 1958 and a correlation with different impeller types and tank sizes was developed (5) ... 

Precision mass and volumetric methods use very precise measurements of pressure and/or level in the tank to detect leaks. The tank must be closed so that no Hquid enters or leaves the tank. The threshold of detection and fuimel required to perform a rehable test become greater as tank size increases. 

With turbulent flow, shear stress also results from the behavior of transient random eddies, including large-scale eddies which decay to small eddies or fluctuations. The scale of the large eddies depends on equipment size. On the other hand, the scale of small eddies, which dissipate energy primarily through viscous shear, is almost independent of agitator and tank size. 

Continuous clarifiers generally are employed with dilute suspensions, principally industrial process streams and domestic municipal wastes, and their primary purpose is to produce a relatively clear overflow. They are basically identical to thickeners in design and layout except that they employ a mechanism of hghter construction and a drive head with a lower torque capability. These differences are permitted in clarification applications because the thickened pulp produced is smaller in volume and appreciably lower in suspended solids concentration, owing in part to the large percentage of relatively fine (smaller than 10 Im) solids. The installed cost of a clarifier, therefore, is approximately 5 to 10 percent less than that of a thickener of equal tank size, as given in Fig. 18-94. 

Design Critena Pertinent criteria for quench tank sizing and design are presented below ... 

Use of dedicated reactant charge tank sized only to hold amount of reactant needed... 

Use dedicated catalyst or initiator charge tank sized to hold only the amount of catalyst needed... 

Note Interpolate for intermediate tank sizes. Tanks with a capacity of more than 180,000 barrels require individual study. Refer to Appendix A for additional information about the basis of this table. 

A 26,000 gallon outdoor vertical storage tank contains benzene. The tank is not insulated, but has a dike around it tvith a volume equal to one-and-a-half times the volume of the tank. Size 15 diameter X 20. Tank does not have weak roof. Temp. = 60°F, pressure = 14.7 psia. 

Latent heat of vaporization 169 BTU/lb Tank size (nominal) 15 diameter and 20 high Operating pressure 1.5 oz/in. ... 

The critical feed time t it depends on the location and number of feed pipes, stirrer type, and mixing intensity, and increases with increasing reactor volume. When a constant power-to-volume ratio is preserved, ta-u is proportional to and where D., is the stirrer diameter and Vr the reactor volume (Bourne and Hilber, 1990 Bourne and Thoma, 1991). The productivity of the reactor expressed as the amount of product formed per unit time becomes almost independent of reactor volume. The reason is that the reaction goes to completion in the zone nearby the stirrer tip. The size of this zone increases independently of the tank size it only depends on the velocity of the liquid being injected, the location of the nozzle, and the stirrer geometry and speed of rotation. Accordingly, for rapid reactions, the feed time will also be the reaction time. 

Vertical cylindrical tanks, with flat bases and conical roofs, are universally used for the bulk storage of liquids at atmospheric pressure. Tank sizes vary from a few hundred gallons (tens of cubic metres) to several thousand gallons (several hundred cubic metres). 

Method Cyanide is destroyed by reaction with sodium hypochlorite under alkaline conditions. System component Reaction tanks, a reagent storage and feed system, mixers, sensors, and controls two identical reaction tanks sized as the above-ground cylindrical tank with a retention time of 4 h. Chemical storage consists of covered concrete tanks to store 60 d supply of sodium hypochlorite and 90 d supply of sodium hydroxide. 

Determine whether it is more economical for a 150,000,000 lb/yr polystyrene plant to buy styrene in 3,000-ton or 1,000-ton shipments. The cost of shipping is 0.230/ton mile in the former case and 0.260/ton mile in the latter case. The distance to be shipped is 1,250 miles. Assume the former requires a 26-day storage capacity and the latter a 17-day storage capacity. (See example in Chapter 3.) The value of money is 10%. Use the tank sizes given in Table 5-2 only. The Net Present Value method should be used. 

For OSBL area the tank sizes are normally not known in conceptual design, which means that the OSBL inventory cannot be readily calculated. The OSBL inventory is not only dependent on the ISBL process type but also local conditions, logistics etc. 

Sampling, including position of sampler inlet or device in the flow or tank, size of strainer, hose diameter and minimum flow rate for the sampling line,... [5,6]... 

A power curve is a plot of the power function 4> or the power number Po against the Reynolds number for mixing ReM on log-log coordinates. Each geometrical configuration has its own power curve and since the plot involves dimensionless groups it is independent of tank size. Thus a power curve used to correlate power data in a 1 m3 tank system is also valid for a 1000 m3 tank system provided that both tank systems have the same geometrical configuration. 

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