Heat exchanger shell pass

Column with random packing (see Table 2-27) or tower with random packed tubes (heat exchange possible to a cooling agent on the shell side). Specific surface 50-300 mVm diameter up to 2.5 m vapor load factor 1-2.5 Pa trickle density 2-100 m / (m h) specific pressure drop 20-120 mm water gauge gas and liquid phase are both continous. 

For the crude preheat train in the refinery plant, three beneficial modifications are identified. Modifications 1 and 2 add a new shell to each of the feed preheat exchangers serviced by the diesel pump-around (PA). Modification 3 adds surface area to the diesel product run down heat exchanger. Before implementing these changes, it is crucial to make sure that the existing pump can handle the increased diesel PA flow and the increase can be tolerated in product cut points. These modifications can save 47 million Btu/h of fuel in the crude heaters, equating to cost savings of 2.3 million per year. With only a 2.2 million installed cost, this project provides a fast payback. 

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