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Normalized differential pressure

Normalized differential pressure as a function of time. Data courtesy of Madalyn Epple, Toray Membrane, USA, Inc. [Pg.249]

Case Normalized Permeate Flow Normalized Salt Passage Normalized Differential Pressure Location Probable Causes... [Pg.288]

For an externally seal-flushed pump, open the seal flush flow and adjust the seal flush pressure to the manufacturer s recommended pressure above the suction pressure. If this data is not available, use the pump suction pressure plus 10 percent of the pump s normal differential pressure. The seal flush pressure should not be close to the discharge pressure. This will damage the seal. [Pg.503]

Cahbration of some measurement devices involves comparing the measured value with the value from the working standard. Pressure and differential pressure transmitters are calibrated in this manner. Calibration of analyzers normally involves using the measurement device to analyze a specially prepared sample whose composition is known. These and similar approaches can he applied to most measurement devices. [Pg.759]

Flow is an important measurement whose calibration presents some challenges. When a flow measurement device is used in applications such as custody transfer, provision is made to pass a known flow through the meter. However, such a provision is costly and is not available for most in-process flowmeters. Without such a provision, a true cahbration of the flow element itself is not possible. For orifice meters, calibration of the flowmeter normally involves cahbration of the differential pressure transmitter, and the orifice plate is usually only inspected for deformation, abrasion, and so on. Similarly, cahbration of a magnetic flowmeter normally involves cahbration of the voltage measurement circuitry, which is analogous to calibration of the differential pressure transmitter for an orifice meter. [Pg.759]

Fluetuations in the flue gas flowrate (typieally less than 3% of nominal) are deteeted by the differential pressure eontroller and eompensated for by adjusting the small bypass valve. The main bypass valve is eompletely elosed during normal operations, but ean open in the event of sharp inereases in the flue gas flowrate. Similarly, in the event the flue gas flowrate deereases, the small bypass valve eloses to a meehanieally preset minimal opening, and the inlet eontrol valve also partially eloses. The minimum opening is neeessary to keep the bypass lines to the minimum requisite operating temperature. [Pg.384]

Under normal operations, the existing differential pressure governor is switehed to manual and the double slide valve is wide open. This valve must be suffieiently opened so that, even in the event of an emergeney expander trip, the entire flue gas flow ean pass through the double slide valve without the regenerator diseharge pressure inereasing to nonpermissible levels. [Pg.384]

Filtration should be 10 mierons nominal. For hydroearbon and synthetie oils, the pressure drop for elean filters should not exeeed five psi at 100°F operating temperature at normal flow. Cartridges will have a minimum eollapsing differential pressure of 50 psi (3.447379 Bars). [Pg.546]

The depth-type filter elements are used when the oil is free from water, and when particles sizes to be removed are in the five-micron and greater range. Generally, the depth-type element is water-sensitive, and when oil is contaminated with moisture, this element type will absorb the water and produce a rapid increase in differential pressure across the filter. The desired maximum differential pressure across a filter with clean elements is five psig at normal operating temperature. [Pg.551]

Condensate normally flows at the bottom of a return line. It flows because of the pitch in the pipe and also because of the higher velocity flash steam above it, dragging it along. The flash steam moves at a higher velocity because it moves by differential pressure. [Pg.314]

It is desirable to have additional axial-load control on the multistage compressor. A balance piston, also refeired to as the balance drum, can be located at the discharge end (see Figure 5-46). The balance piston consists of a rotating element that has a specified diameter and an extended rim for sealing. The area adjacent to the balance piston (opposite the last stage location) is vented, normally to suction pressure. The differential pressure across the balance piston acts on the balance piston area to develop a thrust force opposite that generated by the impellers. The pressure on the... [Pg.208]

For liquid film seals, an overhead tank is normally used. The tank functions as part of the differential pressure control. The process gas is referenced to the top of the tank, and the tank s physical height becomes a manometric leg. The oil level is controlled in the tank. Figure 8-11 shows an alternate arrangement for the overhead seal tank, including the recommended operating levels and volumes. The material of the seal oil tank should be stainless, the same as that recommended for the accumulator. [Pg.319]

For the double-opposed seal, normally an inert gas is injected between the two opposed seals. This gas is pressure controlled to maintain a differential pressure higher than the process side pressure. The supply to this seal is critical because a failure will permit the differential pressure across the outer seal to reverse, which will result in a seal failure. This seal arrangement usually incorporates a buffer to the process side of the... [Pg.326]

The balance of the controls consists of the required pressure switches and/or transmitters to provide monitoring of the system and alarm and shutdown functions for the critical buffers. Filter differential normally is also monitored and alarmed on high filter differential pressure. [Pg.327]

The driving force for the separation is differential pressure. CO2 tends to diffuse quickly through membranes and thus can be removed from the bulk gas stream. The low pressure side of the membrane that is rich in CO2 is normally operated at 10 to 20% of the feed pressure. [Pg.178]

Compressors are used whenever it is necessary to flow gas from a lower pressure to a higher pressure system. Flash gas from low-pressure vessels used for multistage stabilization of liquids, oil treating, water treating, etc., often exists at too low a pressure to flow into the gas sales pipeline. Sometimes this gas is used as fuel and the remainder flared or vented. Often it is more economical or it is necessary for environmental reasons to compress the gas for sales. In a gas field, a compressor used in this service is normally called a flash gas compressor. Flash gas compressors are normally characterized by low throughput rate and high differential pressure. [Pg.253]

Normally, the reactor temperature and the stripper level controllers regulate he movement of the regenerated and spent catalyst slide valves, le algorithm of these controllers can drive the valves either fully Of [ or fully closed if the controller set-point is unobtainable. It is ext nely important that a positive and stable pressure differential be mail ined across both the regenerated and spent catalyst slide valves. r safety, a low differential pressure controller overrides the tempera re/level controllers should these valves open too much. The shutdov is usually set at 2 psi (14 Kp). [Pg.178]

Bags are normally reusable after cleaning and may last for several cycles before changing becomes necessary. Bags should be cleaned or changed when differential pressure reaches 20 to 25 psid. [Pg.325]


See other pages where Normalized differential pressure is mentioned: [Pg.246]    [Pg.248]    [Pg.250]    [Pg.379]    [Pg.248]    [Pg.250]    [Pg.201]    [Pg.300]    [Pg.300]    [Pg.246]    [Pg.248]    [Pg.250]    [Pg.379]    [Pg.248]    [Pg.250]    [Pg.201]    [Pg.300]    [Pg.300]    [Pg.20]    [Pg.181]    [Pg.1564]    [Pg.1570]    [Pg.43]    [Pg.517]    [Pg.116]    [Pg.187]    [Pg.193]    [Pg.252]    [Pg.364]    [Pg.365]    [Pg.138]    [Pg.139]    [Pg.204]    [Pg.147]    [Pg.263]    [Pg.325]   
See also in sourсe #XX -- [ Pg.297 ]




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