Condensate drum connection

One important feature of Fig. 8.6 is the condensate drum balance line. Note, that this line is connected below the channel head pass partition baffle. This ensures that the pressure in the channel head, below the pass partition baffle, and the pressure in the condensate drum, are the same. If these two pressures are not identical, then the level in the condensate drum cannot represent the level in the channel head. For this reason, never connect the condensate drum vapor space to either the steam supply line or the top vent of the reboiler s channel head. 

Condensate drum balance line Used to connect the channel head of a steam reboiler to the condensate drum for pressure balance. 

A typical non-condensible blowdown drum and its associated equipment and headers are illustrated in Figure 1. A single blowdown drum may be used for more than one process unit, if economically attractive. However, when this is done, all units served by it must be shut down in order to take the drum out of service, unless cross connections are made to another system of adequate capacity. Normally all closed safety valve discharges are combined into one header entering the drum, although separate headers and inlet nozzles are acceptable if economically advantageous. The following releases are also normally routed into the safety valve header ... 

In large boiler plants, carryover is measured by employing a singleport sampling nozzle connected to a steam supply line between the top drum and the superheater. Sampling from superheaters is difficult, however, because a pump is needed to inject cool condensate water into a double-walled sample probe (via an attemperating nozzle). This is to remove the degrees of superheat and thus reduce the tendency for any contaminants to deposit in or on the sample probe, rather than be collected with the steam. 

The solution is introduced into the drum, which is then closed with a lid and set in motion for one or more hours. A side lid is then opened permitting alcohol to evaporate thereby gradually predrying the powder. During the latter operation a small amount of graphite is added so that its total content amounts to 0.25-0.3%. The evaporation of alcohol from the drum may be combined with the recovery of this solvent. For this purpose the lid is not removed but connected with a duct producing a reduced pressure within the drum. The solvent thus drawn off is then recovered either by condensation or adsorption. 

In the lower part of each vessel is the calaiidria or steam drum formed by two plates fitted with vertical copper tubes, through which the juice can circulate from the lower part of the vessel to rise just above the top of the calandria, and as it boils and thickens the vapour passes into the calandria of the next vessel. The juice in this makes it act as a surface condenser and assist the boiling in the first vessel, while the vapour of the second vessel enters the calandria of the third vessel, which is connected to the vacuum pump. The steam supplied to the first vessel thus brings about an evaporation nearly three times what it would do in a single vessel, and secures the economy in fuel which has made the... 

An iron drum(seeFig. lll)providedwitha cooling jacket serves as reaction vessel. It connects to an inclined iron condenser, followed by two quartz traps. 

After leaving the autoclaves the ammonia gas is washed and dried by being passed through a series of mud drums and an installation of 7 ammonia columns each 9 feet in diameter by 19 feet high connected by 14 inch pipe to 7 de-phlegmators each 7 feet 2 inches in diameter by 8 feet 3 inches high and 7 condensers similar In size to the dephleg-mators. P rom the condensers, the ammonia gas is stored in two 60,000 cubic feet gas holders. 

Forget about the rat. I made that story up. The real story is that the riser pipe connecting the condenser outlet to the reflux drum was undersized. Nat Taylor, the project engineer, specified a 4-inch pipe when an 8-inch pipe was needed. The pressure drop through the pipe was then 32 times higher than the intended AP of 0.60 psig (AP in a pipe varies to the fifth power of the pipe s diameter). The resulting riser pipe pressure drop was 20 psi. This frictional loss of 20 psi in the pipe had the exact same effect on the condenser— and on the tower s pressure— as the 20-lb rat. 

The PANDA-PCC consists of 20 vertically arranged tubes connected at their ends with drum-type headers. The upper header has a connection for steam supply, the bottom header has a drain for the condensate produced and a drain for non-condensable gases. The tubes of the PCC have an outside diameter of 50.8 mm and a wall thickness of 1.65 mm. They are made of austenitic steel. 

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