Condensate collection

Figure 9-11. Condensate collected in a steam main. A valve was opened quickly. Sudden movement of the condensate fractured another valve. The figure explains how this occurred.

Within any particular facility, steam is expected to be delivered to various points of use safely and at controlled temperatures and pressures through relatively long-lasting distribution networks. Where the steam is not excessively contaminated or directly consumed in a process as live steam, it should be condensed, collected, and returned to the boiler for reuse. Thus, the post-boiler section of a boiler plant essentially relates to the systems concerned with steam distribution and condensate return (CR). 

Transfer the reaction product to a 500 ml. Claisen flask and distil over a wire gauze or from an air bath. Some acetyl chloride and acetic acid passes over first, the temperature then rises, and the fraction, b.p. 150-200°, is collected separately run out the water from the condenser when the temperature reaches 150°. The fraction, b.p. 150-200°, solidifies on cooling. Drain off any hquid from the crystals as rapidly as possible, and redistil the solid using an air condenser. Collect the fraction b.p. 182-192° this sets to a sohd mass on cooling and melts at 63°. The yield of monochloroacetic acid is 150-175 g. 

Consider the binary batch distillation column, represented in Fig. 3.58, and based on that of Luyben (1973, 1990). The still contains Mb moles with liquid mole fraction composition xg. The liquid holdup on each plate n of the column is M with liquid composition x and a corresponding vapour phase composition y,. The liquid flow from plate to plate varies along the column with consequent variations in M . Overhead vapours are condensed in a total condenser and the condensate collected in a reflux drum with a liquid holdup volume Mg and liquid composition xq. From here part of the condensate is returned to the top plate of the column as reflux at the rate Lq and composition xq. Product is removed from the reflux drum at a composition xd and rate D which is controlled by a simple proportional controller acting on the reflux drum level and is proportional to Md-... 

Samples are injected into the vaporizer by a metering pump or manually with septum injection the manual injection procedure is intended for method development. The sample gas mixture then passes through the chromatographic column where the sample compounds separate. Fractions pass through the thermal conductivity detector and then to a condenser collection manifold where up to five fractions can be collected. Complete control of the system is achieved via a mini-computer. 

A thermostatic steam trap to efficiently remove condensate from the chamber. This is open when cool and closed when in contact with steam. As condensate collects, the trap opens due to the slight temperature reduction, and the condensate is discharged. There is also a trap to remove condensate from the steam jacket. 

Once the steam pressure in the channel head of Fig. 8.4 falls to the pressure in the condensate collection header, the steam trap can no longer pass condensate. Water will back up in the channel head, and water-log the lower tubes in the tube bundle. This will lead to unstable steam flow control. This is especially true if the steam supply pressure is less than 20 psig higher than the maximum condensate collection header pressure. 

How much steam condensate is your plant recovering Seventy percent is considered pretty good, and 30 percent is, by any standard, pretty awful. As condensate collection flows are rarely metered, here is a really good way to make such an overall measurement (ST = steam TR = treated water) ... 

It creates steam or water hammer in the condensate collection system. 

Backpressure from the condensate collection lines creates control difficulties in steam reboilers or heaters. 

Figure 8.8 Avoiding water hammer in a condensate collection system.

Trifluoropropane (1342 g, 13.7 mol), HN03, and 02 (molar ratio 9.9-11.9 1 0.1-0.15) were treated at atmospheric pressure in the gas phase at 437-462 C for an exposure time of 1.7-2.0 s. Condensate collected at 0°C in the first trap and. after an aliquot was titrated for nitric acid (NaOH), was immediately extracted with Et20. The condensate collected at — 80 C in the second trap was distilled at atmospheric pressure to remove unreacted 1,1,1-trifluoropropane, then extracted with Et20. The ethereal extracts were combined, dried (Na2SQ4), and fractionally distilled on a packed column (80 x 1.5 cm, helices). After... 

The vapor is then condensed on a cool surface and the condensate collected as product water. 

Free cyclohexene from peroxides by treating it with a saturated solution of sodium metabisulphite, separate, dry and distil collect the fraction having b.p. 81-83°C. Mix 8.2 g (0.1 mol) of cyclohexene with 55 ml of the reagent (0.1 mol), add 3 ml of a 0.5 per cent solution of osmium tetroxide [CAUTION (1)] in anhydrous t-butyl alcohol and cool the mixture to 0°C. Allow to stand overnight, by which time the initial orange coloration will have disappeared. Remove the solvent and unreacted cyclohexene by distillation at atmospheric pressure and fractionate the residue under reduced pressure using an air condenser. Collect the fraction of b.p. 120-140 °C/15 mmHg this solidifies almost immediately. Recrystallise from ethyl acetate. The yield of pure cis-cyclohexane-l,2-diol, m.p. 96 °C, is 5.0g (45%). 

Bridgman, P. W. (1936). Condensed Collection of Thermodynamic Formulas. Cambridge, MA Harvard University Press. 

Several local newspaper articles explained that during these startups, steam is provided to displace any air in the system prior to the introduction of any oil. At the beginning of the startup, temperatures in the unit are cool enough to condense some of the steam into water. Water (steam condensate) collects in the E-l Fractinator and then is pumped into another part of the unit, the F-7 Drum. Under normal startup procedures the operating crew drain all of the water from the F-7 Drum before the hot oil is admitted. 

Step 2. Set the rheostat to boil the water gently. Distill the water sample and collect 11 mL or more of the distilled water in the condensate collection vessel. 

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