http://chemengservices.com/exchanger-services.html Solving Heat Exchanger Problems
Excessive Load
Due to increased plant capacity, or high fluid temperature differences, greater heat transfer than originally designed for the heat exchanger often exists. In such instances, the outlet temperature of one of the streams may depart from optimum conditions. The disadvantage in operating such equipment may be continuous greater energy use of interrelated equipment, harmful effects on the capacity of portions of a plant, or restricted capacity for the overall plant. Improvements can result from heat exchanger services and upgrade heat exchanger engineering, which involve identifying the optimal process conditions for new equipment design, and, the assessment of the resulting benefits for achieving those conditions, and finally optimally designing upgrade heat exchanger equipment to accomplish the plant desired goals for improvement. Gradual Fouling Buildup, Harming Heat Transfer
Depending on the service, certain heat exchanger equipment is more likely to develop fouling substances buildup, causing decreasing heat transfer, which may also harm plant or equipment efficiency, capacity, or both, and may also cause continuous higher plant energy use. Heat exchanger fouling exists for many heat exchanger services, but it is particularly troublesome in process cooling, where recycled cooling water from a cooling tower is used for cooling. In such equipment, fouling can result from large temperature differences, accumulation of or precipitation of solids on heat transfer surface, as well as other thermalmechanical design considerations of the heat exchanger equipment. !pgrading of process coolers through optimi"ed heat exchanger engineering can achieve improved resistance to fouling, through careful control in design of fluid velocities and temperatures, as well as from proper selection of materials of construction and use of the best heat exchanger type. Decreasing heat transfer resulting from equipment fouling usually lowers both plant capacity and efficiency over time, and damaged performance is usually only improved by plant shutdown for the heat exchanger to be cleaned. #ll plants want to minimi"e this down time, so optimum exchanger designs in heat exchanger engineering should minimi"e the effects of fouling, to fully maximi"e production and run time. $hen cleaning becomes necessary, usually hydroblasting or chemical cleaning procedures can be successful in restoring the best performance for the heat exchanger. In rare cases, speciali"ed cleaning techniques may be necessary for hard to clean applications. Excessive Stream Pressure Loss
$hen heat exchanger equipment is originally supplied in a new plant, optimal si"e and selection in the heat exchanger engineering should have been performed to support efficient plant operation. That is, a range of heat exchanger equipment si"es %designs& should have been studied to specify the most favorable economic design with attractive economic performance for the equipment, considering energy costs during that time. 'ometimes this is not the case. $hen large plant contractors develop (standard plant designs( to offer clients, they reuse ma)or sections of previous plant designs which will achieve the venture client*s requirements, usually for higher capacity.
#lso, over time, plants may be gradually upgraded with improvements in subsections of the plant site, resulting
