Water slug

In the study by Qu et al. (2004), experiments were conducted with adiabatic nitrogen-water two-phase flow in a rectangular micro-channel. The bubbly, stratified and churn flow patterns commonly encountered in macro-channels were never observed in the study. No water droplets were observed in the nitrogen bubble, nor were any nitrogen bubbles present in the water slugs. 

Using the dangerous water expansion example, compute the approximate pressures that were developed in the bottom of this column. Assume a column diameter of 2 ft, a water slug of 1 gal, and a column pressure of 10 psia. 

The hardware is shown in Figure 12—1. To protect the compressors, a water knockout column in front is necessary. It keeps water slugs from forming during compression, sending turbine blades flying all around the plant. 

Walmsley, H.L., Electrostatic Hazards from water slugs formed during the washing of ships tanks Spark energy calculations, J. Phys. D Appl. Phys. 20, 329-339, 1987. 

Equal size water slug injected in 0.05 HCPV increments in WAG or continuously in foam operation. 

Cases OSP5 and OSP6 are really interesting. These cases are based on Case kr4. In Case OSP5, the salinity of 1.0 PV chase water is 0.340, just below Csei, which is equal to 0.345. The RF is 92.94%. In this case, the chase water mis-cibly drive the type ll(-) microemulsion. In Case OSP6, the salinity of chase water is 0.350, just above Csei = 0.345, and the RF is 84.8%. These two cases show that the salinity in the chase water slug should be less than Csei. 

The driver or chase water slug is a solution injected after the polymer slug whose viscosity progressively decreases, ending up as brine [109, 115, 119, 133, 141]. This slug is used, instead of a large polymer slug, to cut down the operation and the chemical costs. 

Figures 13.1 and 13.2 illustrate two refinery case histories of pressure surges resulting from water slugs (4). In Fig. 13.1a, a combination tower fleft) was connected by a long horizontal line to coke drum (right). Upon heating, the tower expanded and lifted the tower-end of the line...

Attentive review of capacity and reliability of safety valves also for fluid conditions during an accident (water slugs, etc.). 

A sequence like the one described might happen, for example after a small break LOCA, after a PRISE (primary to secondary leak) accident, after an ATWS or after a total Loss of Feed-Water. This possible phenomenon must be taken into account in the Emergency Operating Procedures, since fast operator action will prevent the accumulation of unborated water slugs. As in many... 

Fig. 12. The effect of an intermittent 0.4 PV tap water slug on polymer concentrations in produced water...

FIGURE 17-4 Water slugs trip pump to protect fractionator. 

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