Level plugged taps

Excessive concentrations of silicone or inhibitor Charcoal filter Condensing hydrocarbons Extraneous surfactants Plugged level control taps Liquid-liquid scrubbers... 

Water is drained off the boot to maintain an interface level between water and hydrocarbon in the boot. These interface level controllers, especially on reflux drum water draw-off boots, are typically set locally. The operator finds the visible interface level in the boot s gauge glass, and then sets the local interface level controller, to hold the level half way down the boot. Level taps in the lower portion of any vessel, tend to plug. This is especially true with the level taps in water draw-off boots. You need to blow out these taps on some frequent basis, because a high boot interface level can push water into the tower s reflux pump. 

The atmosphere is the global reservoir of redox power. The level of oxidant in the air is not set by the various fluxes, but by the switches that control input and output gates. Consider a bathtub. Within wide limits, in a bathtub, the level of water is not set by the flow of water out of the tap, but by whether the plug is in or not. If the plug is in, even a dripping tap will eventually flU the tub so that it spills from the overflow. There is no obvious relationship between tap flow and height of water in the tub. Instead, the level of the reservoir is set by an external physical factor, the height of the over-... 

Into the base of the clean empty chromatographic column, place a plug of cotton wool (not too tightly packed) and pour onto a small amount of sand. The cotton wool plug is used to prevent the stationary phase pouring out of the column. Tap the column carefully so that the sand is level. Some columns have a porous glass frit located at the bottom of the column prior the tap, in these cases, it is not necessary to pour in sand or use a cotton wool plug. 

Fig. 8.4 Identical steady states in identical tanks. If two identical tanks are studied with identical input flows and identical plug-holes, they will reach the same steady-state level. Nothing of this will change if the partition separating them is removed, so that they become one tank with two taps and two plug-holes...

The elevation of the pressure-sensing tap does not necessarily have to be at the elevation desired for the neutral pressure plane. The most desirable height for the zero pressure plane may be at a point that turns out to be bad for good measurement, for example, below the hearth, at a level where scale might plug the pressure tap, or in a place where liquid metal may splash into the tap. In such cases, a very workable solution is to locate the sensor tap at a convenient higher position and then adjust the controller s setpoint in accordance with the correction for the rise in pressure for the chosen higher elevation from table 6.2. (See example 6.2.)... 

A hole is drilled into the masonry, using a masonry drill of the same diameter, to the length of the plastic plug (see Fig. 3.65). The plastic plug is inserted into the hole and tapped home until it is level with the surface of the masonry. Finally, the... 

Dry Pack Method 2. An alternative dry pack method for microscale columns is to fill the Pasteur pipette with dry adsorbent, without any solvent. Position a plug of cotton in the bottom of the Pasteur pipette. The desired amount of adsorbent is added slowly, and the pipette tapped constantly, until the level of adsorbent has reached the desired height. Figure 19.7 can be used as a guide to judge the correct height of the column of adsorbent. When the column is packed, added solvent is allowed to percolate through the adsorbent until the entire column is moistened. The solvent is not added until just before the column is to be used. 

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