Condenser pipes

Calculation of condensate piping by two-phase flow techniques is recommended however, the tedious work per line can often be reduced by using empirical methods and charts. Some of the best are proprietary and not available for publication however, the Sarco method [42] has been used and found to be acceptable, provided no line less than VA" is used regardless of the chart reading. Under some circumstances, w hich are too random to properly describe, the Sarco method may give results too small by possibly a half pipe size. Therefore, latitude is recommended in selecting either the flow rates or the pipe size. 

Condensation occurs constantly in steam pipes, and steam traps are installed to separate the steam from the condensate. In long steam-pipe runs most of the carbon dioxide remains in the steam phase, although if only a single neutralizing amine with a low DR is used, much of the amine will be present in the condensate. The result is that the amine feed quickly becomes depleted, and further down the steam/condensate pipe the pH level becomes progressively lower. 

Amino,2-methyl,1-propanol (AMP), also known as Isobutanolamine (IBA), (CH3)2CNH2CH2OH, MW = 89. Available as a 95% solution (AMP-95 ) from Angus Chemical Company. Sp. gr. = 0.942. Flash point = 87 °C/188 °F (PMCC). Boiling point = 329 °F. Suitable for short to medium steam-condensate pipe runs provided the operating pressure is at least 75 psig. A safe replacement for morpholine. Reasonable thermal stability. 

Cooling system failure could occur due to failure of pumps or controls supplying cooling media to the reactor vessel jacket, coils, or overhead reflux condensers. Piping to or from the condensers could become plugged or any of the heat exchange surfaces could become excessively fouled. 

Steam condensate piping safely designed 14.Relief valve piping designed to prevent ... 

Check water traps, siphons, and condensate pipe. 

All the boxes ara in communication with one another by a short connecting pipe passing from one to the other near the bottom the samo level of liquid is thus Insured in all. To prevent the condensing pipes ever getting too hot, a conduit,... 

This cycling can be eliminated by mounting the control valve in the condensate pipe, but this creates new problems, because when the load decreases, the process is slow steam has to condense before the condensate level is affected, and when the load increases, the process is fast, because blowing out liquid condensate is fast. With such "nonsymmetrical" process dynamics, control is bound to be poor. A better option is to use lifting traps to prevent condensate accumulation. These pumping traps will make temperature control possible even when the heater is under vacuum, but will not improve the problem of low rangeability, and the possible use of two control valves in parallel can still be necessary. 

Other applications of this alloy are in roofs, gutters, architectural features, tubes of boiler water heaters, sheathing in seawaters, HF alkylination process, handling of HF, refining of uranium, distillation and condensation units, overhead condenser pipes in refineries and the petrochemical industry. 

The first proposals for the employment of electrical heating in the production of phosphorus were made by Headman, Parker and Robinson.5 The simultaneous production of an alkali silicate by heating alkali phosphate, silica and carbon in a regenerative furnace was patented by Folie-Desjardins.6 In the Readman-Parker-Robinson process, as worked later, the phosphate, carbon and fluxes, previously heated to a high temperature, are introduced into the upper part of an electric furnace made of iron lined with refractory bricks and fitted with condensing pipes in its upper part. The gases pass through a series of copper condensers, the first of which contains hot water, the others cold water (or see p. 9). It has been found advisable to replace... 

The computer program PROG37 evaluates the pressure drop of any given condensate header. The program also determines whether the velocity of the flashed condensate mixture would cause deterioration in the header line. Table 3-15 illustrates the results for the 4-, 6-, and 8-inch headers. Table 3-16 shows a typical input data and computer output for the 4-inch (Schedule 40) pipe. The computed results show that the 4-inch pipe gives the velocity of the flashed condensate mixture to be 7055 ft/ min. This indicates a possible deterioration in the pipe. For the 6- and 8-inch pipes, the velocities are 3109 ft/min, and 1795 ft/min respectively, indicating that the condensate pipe lines will not deteriorate. 

The volatile antimony trioxide is deposited on condensation pipes, e (Fr. tuyaux d ailettes), in the condensing chambers, d, by the aid of the two ventilators, h. 

The primary applications of PVC include hot water and/or steam condensate piping, corrosive chemical piping at elevated temperatures, valves, fume ducts, internal column packing, and miscellaneous fabricated items. Reference [2] provides detailed information on CPVC piping. 

Piping arrangements are very important [25]. Pressure drops must be very low because of the low absolute pressure on the gas side and the use of flashing gravity flow on the liquid side. Condensate piping between condensers and hotwells should have a... 

Certain metals corrode at an abnormally high rate when the flow velocity in the turbulent flow regime exceeds a critical value. The phenomenon is well known for copper and its alloys used in domestic hot water systems and in heat exchanger tubes. Table 10.26 indicates empirical values for the critical flow velocity of seawater in condenser pipes made of different alloys. Similar values apply for fresh water. 

Table 10.26 Critical velocities for seawater in condenser pipes [15].

Particularly susceptible to damage from cavitation corrosion are, for example, ships propellers, condenser pipes, pump impellers, widened segments in pipelines or flow channels. 

A special form of crevice corrosion was observed in crevices between superferrite and austenitic standard steels in condenser pipes. Corrosion products, which lower the pH levels in the crevice, cause depassivation and increased corrosion on the ferritic steel. This form of corrosion, also known as dissimilar metal crevice (DMC) corrosion, does not occur with the combination of superferrites and superaustenites [115]. 

Parts made of the steel SAE 304 (X5CrNil8-10, DIN-Mat. No. 1.4301) were damaged by crevice corrosion after less than 6 months, whereas bolts made of the same material used as fasteners for unalloyed steel or aluminium were not damaged [114]. In condenser pipes cooled with seawater, the steels of the SAE 304 series failed after brief exposure due to massive pitting and crevice corrosion. [148]. The material also reacts to addition of chlorine to prevent fouling with an increased susceptibility to pitting corrosion [149]. 

Long-term studies of condenser pipes made of the austenitic steels (DIN-Mat. No. 1.4438, X2CrNiMol8-5-4, 1.4439, X2CrNiMoN17-13-5 and 1.4558, X2NiCrAlTi32-20) under quasi-industrial conditions of thermal seawater desalination confirm that the pitting resistance equivalent of these steels increases with increasing molybdenum content, but also that a content level of 4.16% Mo was not sufficient to prevent pitting corrosion under the test conditions. In this test in brine 3.5-10% salt content, a pH level of 6.5-7 and a temperature of max. 401 K (128°C), only the pipes made of titanium showed complete resistance [140]. 

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