Separators pressure

The oil and gas samples are taken from the appropriate flowlines of the same separator, whose pressure, temperature and flowrate must be carefully recorded to allow the recombination ratios to be calculated. In addition the pressure and temperature of the stock tank must be recorded to be able to later calculate the shrinkage of oil from the point at which it is sampled and the stock tank. The oil and gas samples are sent separately to the laboratory where they are recombined before PVT analysis is performed. A quality check on the sampling technique is that the bubble point of the recombined sample at the temperature of the separator from which the samples were taken should be equal to the separator pressure. 

The end of field life is often determined by the lowest reservoir pressure which can still overcome all the pressure drops described and provide production to the stock tank. As the reservoir pressure approaches this level, the abandonment conditions may be postponed by reducing some of the pressure drops, either by changing the choke and separator pressure drops as mentioned, or by introducing some form of artificial lift mechanism, as discussed in Section 9.7. 

Pervaporation operates under constraints similar to low pressure gas-separation. Pressure drops on the permeate side of the membrane must be small, and many prevaporation membrane materials are mbbery. For this reason, spiral-wound modules and plate-and-frame systems ate both in use. 

Four separate pressure gauges read at expander inlet, taps located about one pipe diameter from expander flanges located in spool piece, 90° apart. 

Two separate pressure gauges read at the flow measuring section, 180° apart. 

The fix for the erratic reflux drum pressure problem was to provide for separate pressure control of the fractionator column and the reflux drum. A new pressure control valve was installed upstream of the condenser and the old condenser outlet control valve was removed. A hot gas bypass, designed for 20% vapor flow, was installed around the pressure control valve and condenser. A control valve was installed in the hot gas bypass line. The column pressure was then maintained by throttling the new control valve upstream of the condenser. The reflux drum pressure w as controlled by the hot gas bypass control valve and the psv saver working in split range. The new system is shown in the figure below. 

A vapor poeket on the exchanger s low-pressure side can create a cushion that may greatly diminish the pressure transient s intensity. A transient analysis may not be required if sufficient low-pressure side vapor exists (although tube rupture should still be considered as a viable relief scenario). However, if the low-pressure fluid is liquid from a separator that has a small amount of vapor from flashing across a level control valve, the vapor pocket may collapse after the pressure has exceeded the fluid s bubble point. The bubble point will be at the separator pressure. Transient analysis will prediet a gradually inereasing pressure until the pressure reaches the bubble point. Then, the pressure will increase rapidly. For this ease, a transient analysis should be considered. 

In many cases, if it is not feasible to contain a runaway reaction within the reactor, it may be possible to pipe the emergency device effluent to a separate pressure vessel for containment and subsequent treatment. 

The reactor had a loop for each half of the core. Each circuit had two steam drums and two. 500 MW(e) turbines. Water was circulated in each of the two circuits by four pumps in parallel (8 lotal), though usually each circuit had three in use and one on standby. The pumps supplied a t omplex of pipes under the reactor that fed water to the separate pressure tubes. 

A vessel can only be overpressured if the upstream vessel has a higher pressure than the vessel in question. A compressor scrubber with a MAWP of 285 that gets flow from a 285 MAWP separator does not need to have a relief valve sized for blocked discharge. The upstream relief valve will keep the upstream separator pressure from going higher than 285, so there is no way it can oveipressure the downstream scrubber. The scrubber PSV only needs to be sized for fire. 

Results have been presented on one experiment. It involved a 5.659-m vessel containing 1000 kg of butane with a fill ratio of 39%. The vessel s contents were heated to 99°C, which is near but still below the supetheat-limit temperature, producing an internal pressure of 14.6 bar gauge. Vessel failure was then initiated. Measured pressure-time histories indicated that a number of separate pressure pulses occurred. They are plotted in Figure 6.6 as the overpressure-time relationship measured at 25 m from the vessel. 

Number of turns made by gas stream in a cyclone separator Pressure drop, Ibs/sq in. 

Separate pressure system similar to lubrication system Including pumps, cooler, filters, etc., or if buffering media is oil, sealing system can be combined with bearing lubrication system. 

Extensive experimental data confirm the fact that the pressure drop for a two-phase system is influenced by the flow pattern, and indicate the need either for separate pressure drop correlations for each flow pattern, or for the incorporation into a master pressure drop correlation of these variables which in fact define the flow pattern. 

Fig. 9. Decline in Cl concentrations with time in water at 10 bars absolute separation pressure discharged from wells at (a) Momtombo, Nicaragua, and (b) Krafla, Iceland. The cause of the decline is cooler water recharge into producing aquifers. Numbers indicate well numbers. From Amorsson (1996) and Gudmundsson Amorsson (2002).

Multiple Separators for More EfOcient Separation of Cholesterol from Beef Tallow. Since the solvent power of CO2 depends upon its density, a step-wise reduction of separation pressure will alter the CO2 density so that the soluble components of beef tallow can be separated and collected in different fractions. 

Hence, currently available test data, current separator pressures, and the need for high reject ratios indicate that the hydrocyclones exhibit high efficiencies from 636 to 1590 mJ/d water [4,000 to 10,000 BWPD] per four-in-ooe 60-nun [2.4-tn.J hydrocyclone (single unit times 4). This gives an operating turndown ratio of 2.5 1. The relationship of efficiency vs. flow rate for the 60-mm (2.4-in.] cyclooe is shown graphically in Fig. 3. 

The electrical power consumption of the refrigerator depends only on the separation condition. The pumping mode is optimal for high extraction pressures (more than 150 bar), low extraction temperatures (40 to 80°C), and separation pressure between 45 and 60 bar. 

Depressurizing valves, reducing the extraction-pressure down to the separation-pressure. Safety valves located in front of -, or directly on the separator, must be large enough to remove the complete possible mass-flow. 

A comparison for the different cases of the production costs and dependence on the annual capacity is given in Fig. 8.1-4. The results are based on the cascade-operation mode, with three extractors, extraction at 280 bar and 65°C, cycle-times of 7.5 hours, and a separation pressure of 60 bar for the non-isobaric process. 

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