Submerged pipe

In the fumace/ketde batch process, a charge of drossed blast furnace buUion is treated in a reverberatory furnace or a kettie (see Fig. 12). Oxygen is supphed in the form of compressed air or as lead oxide blown into the bath through submerged pipes. The formation of lead oxide serves by mass action to assure the removal of the impurities to the desired low concentrations. The softening reactions are... 

NACE Recommended Practice RP-02-75, Application of Organic Coatings to the External Surface of Steel Pipe for Underground Service NACE Recommended Practice RP-08-85, Extruded Polyolefin Resin Coating Systems for Underground or Submerged Pipe... 

GAS DISPERSION IN AGITATED VESSELS. Gas is normally fed to a processing vessel through the open end of a submerged pipe, through a sparger, or through a porous ceramic or metal plate. Sometimes the gas by itself provides sufficient... 

Cathodic protection is an anticorrosion technique widely used in ships and in buried or submerged pipe work. This method seeks to reduce the rate of corrosion of the structure to be protected by joining it to sacrificial anodes. In other words, the structure is joined to another metal (an anode) that corrodes more readily, effectively diverting the tendency to corrode away from the structure. 

The acid can be stored in vertical or horizontal tanks. Normal good practice is to fill a tank through a submerged pipe. In a tall vertical tank, the dip pipe should be secured by a support mounted on the bottom of the tank. The end of the pipe should be at least 500 mm from the tank bottom frequently a wear plate 10-15 mm thick is welded to the bottom to allow for erosion. This can also serve as a support for the dip pipe s guide. Top entry is preferred, under the general principle that it is well to minimize the number of bottom connections. While a side nozzle near the bottom of the shell is sometimes used, it should have an insert that is bent to direct the flow of acid away from the tank bottom. 

Pressure flow Airlift). Basically, the method involves pressurizing a strong-walled vessel and discharging its contents through a submerged pipe or the bottom outlet. 

Destruction of submerged pipes has occurred in a Mark II BWR in Germany due to chugging. 

Submerged pipe [18]. Submerged pipe is mostly applicable for seawater, and Parker et al. recommended that the following empirical equation should be used ... 

Example 9 Pipe Distrihator A 3-in schedule 40 (inside diameter 7.793 cm) pipe is to be used as a distributor for a flow of 0.010 mVs of water (p = 1,000 kg/m, i= 0.001 Pa s). The pipe is 0.7 m long and is to have 10 holes of uniform diameter and spacing along the length of the pipe. The distributor pipe is submerged. Calculate the required hole size to limit maldistribution to 5 percent, and estimate the pressure drop across the distributor. 

Drain pipe design must respect proper submergence (Figure 17-3). The. submergence laws appear later in this chapter. 

A submerged in-flow pipe and tank baffles prevent turbulenee and bubbles from entering the suction piping (Figure 17-7). 

NACE Standard RP-01-69, Recommended practices Control of external corrosion on underground or submerged metallic piping systems. 

The use of fixed plastic tanks is especially problematic for nonconductive flammable liquids because the efficiency of grounding aids (such as a conductive dip pipe or a submerged grounded metal plate) decreases as liquid... 

Where a PR valve on a fractionator is used to protect a distillate drum with submerged inlet, the PR valve must be located on the tower itself, rather than on the overhead piping, or it must be discharged to a closed system. This is to preclude liquid release, should the PR valve discharge under fire conditions at the distillate drum. 

The Seal Drum - A typical flare seal drum for an elevated flare stack is illustrated in Figure 7. A baffle maintains the normal water level, and the vapor inlet is submerged 75 mm to 100 mm. Drum dimensions are designed such that a 3 m slug of water is pressured back into the vertical inlet piping in the event of... 

Submergence of the inlet pipe column or bell inlet below the water level is necessary for good operation and to prevent vortexes and entrained air. The minimum submergence as recommended by the manufacturer must be maintained at all Limes. Generally, for 70°F w ater, each 1000 feet of elevation above sea level adds 14 inches to the... 

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