Tank discharge rate, example

The D(At) values were approximated by a power function, D(At) = a0(At)b. The following values for the parameters were obtained a0 0.7 m and b 0.86. The correlation coefficient was 0.965. The scatter of the points relative to the approximating function could be caused by variations in the oil discharge rate associated, for example, with the variable amount of oil in cleaning waters pumped out from different tanks. The decreased width values in area D were, most likely, due to a spill s disturbance by a... 

This example demonstrates the important point that the incident is selected based on the objective of the smdy. If the objective of the smdy is to determine the maximum discharge rate from the tank, then a hole is specified at the bottom... 

As an example of a dynamic process, consider the process in Figure 1, which is a tank into which an incompressible (constant density) liquid is pumped at a variable feed rate FL (m3 s ). This inlet flow rate can vary with time because of changes in operations upstream of the tank. The height in the tank is h (m) and the outlet flow rate is F (m3 s ). Liquid leaves the tank at the base via a long horizontal pipe and discharges into another tank. Both tanks are open to the atmosphere. F h and Fean all vary with time and are therefore functions of time t. 

A high degree of control can also be achieved in continuously stirred tank crystallizers. Temperature differences between feed and crystallizer can be regulated as necessary. The seed is the product and will normally be present at the slurry concentration as determined by the feed rate, concentration, and solubility differences achieved. However, in cases in which this amount of seed is not sufficient, cross-flow filtration on the discharge of the crys-tallizer(s) can be used to increase the slurry density. See Example 7-4 for a discussion of the resolution of ibuprofen lysinate. 

EXAMPLE 2.7-7. Rate of Flow from a Nozzle in a Tank A nozzle of cross-sectional area A2 is discharging to the atmosphere and is located in the side of a large tank, in which the open surface of the liquid in the tank is // m above the center line of the nozzle. Calculate the velocity 1)2 in the nozzle and the volumetric rate of discharge if no friction losses are assumed. 

A simple example can be used to illustrate the concept of the use of dynamic models in simulation and control. Consider the water tank shown in Figure 3.4, where the valve at the bottom discharges water at a rate proportional to the head /z. It is well known that the discharge is proportional to -Jh-, however, we use the assumption that it is proportional to h in order to make the equations linear and, therefore, illustrate the ideas in a simple manner. 

To modify the rate or spatial distribution of release of the hazard fi om its source. Example Install controls on the discharge gates of a storage bin or pressure refief valves that bleed off pressme before it acciunulates and bursts a tank. 

Example 13-4. Hydraulic Energy Balance. A tank of water at 150 F (specific gravity 0.985, viscosity 0.433 centipoise) is discharging through a standard 2-in. pipe stem at the rate of 120 gal per min by its own hydrostatic head. Figure 13-5 indicates the pipe system. What is the height of the water above the discluu ge point ... 

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