air cooled heat exchanger design manual

air cooled heat exchanger design manual

To browse Academia.edu and the wider internet faster and more securely, please take a few seconds to upgrade your browser. You can download the paper by clicking the button above. READ PAPER Download pdf. If you continue browsing the site, you agree to the use of cookies on this website. See our User Agreement and Privacy Policy.If you continue browsing the site, you agree to the use of cookies on this website. See our Privacy Policy and User Agreement for details.If you wish to opt out, please close your SlideShare account. Learn more. You can change your ad preferences anytime. She had been struggling with her weight pretty much all her life. And seemed to be stuck in a perpetual limbo of weight loss, weight gain, weight loss, weight gain. But when she started doing THIS 7 second daily ritual things rapidly changed. She had fast fat loss from her hips, thighs face and arms.While enjoying an increase in energy and zest for life.I had some fun and got a great deal. ??? Process Engineering Guide:Information contained in this publication or as otherwise supplied to Users isGBHE gives no warranty as to the fitness of thisBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comAir Cooled Heat Exchanger. DesignChoice of Cooling SystemGeneral. Thermal Duty and Design Margins. Process Pressure Drop. Design Ambient Conditions. Process Physical Properties. Mechanical Design Constraints. Arrangement. Air Side Fouling. Economic Factors in DesignWeb Site: www.GBHEnterprises.comManual Checking Of Designs. Computer Assessment. Bid ComparisonCorrosionAir-Side Cleaning. Mechanical Maintenance. Tubeside AccessWeb Site: www.GBHEnterprises.comWeb Site: www.GBHEnterprises.comWeb Site: www.GBHEnterprises.comIt is concerned with such matters as choice of exchanger, specification of duty,It does not aim to give detailed information on the thermal design or rating of. ACHEs.http://fiestadrivingschool.com/phpsites/involve_audio/uploads/ademco-n8743-3-manual.xml

• air cooled heat exchanger design manual, air cooled heat exchanger design handbook, air cooled heat exchanger design manual, air cooled heat exchanger design manual download, air cooled heat exchanger design manuals, air cooled heat exchanger design manual pdf, air cooled heat exchanger design manual diagram.

It is assumed that readers of the Guide have some general knowledge of heatA heat exchanger designed for theBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comA cooperative researchA cooperative researchBefore deciding on the use of air cooling, the alternatives should be consideredMoreover, heat rejected to the environment isThe principal possibilities for process plant heat rejection are:Direct contact cooling.Indirect cooling using a secondary coolant, with sea or river water as theCooling water from an evaporative cooling tower.Cooling water from an air cooled heat exchanger. Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comDirect cooling in an air cooled heat exchanger. Although this Guide is mainly concerned with air cooled heat exchangers, theThis process is normally limited to condensation duties, where there is a readyThis approach, where appropriate, is likely to be one of the cheapest, as theFor more information on directWeb Site: www.GBHEnterprises.comThe heat sink is generally coolest when direct cooling ofAn indirect system, as shown in Figure 3, can be used where one or more of theIf the raw cooling water is particularly corrosive.If it is important that the process cooling water be clean.If the risk of leakage of water into the process is unacceptable. Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comIt is usually cheapest to cool the circulatedThis system may be particularly appropriate where there are several separateBy providing aThis system has the disadvantage that the secondary coolant has to be run at aBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.http://dreamnightwear.com/userfiles/ademco-n6119v1-user-manual.xml

comUn-quantified benefits of theThe major disadvantage was the high cost ofHowever, if the closed circuit enabled the cooling tower to be dispensed with,It is emphasizedThis is the most common form of process cooling recommended by GBH. Enterprises. The evaporative cooling tower of Figure 4 may be fan-blown or useNatural draft towers areWeb Site: www.GBHEnterprises.comOne of the principal problems of evaporative cooling systems is the quality ofAn evaporative system requires a supply of make-up water, the minimumThe system, in general,For further information see consult a. Water Technologist.No example of a dryBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comSee Figure 6. Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comIf the direct air cooler has to be made of expensive material, there may beLow pressure gases tend to require a high ratio of pressure drop toFreezing or control problems might be eased by adopting an indirectAn indirect system using recirculated condensate with a jet condenser (theStraight forward air cooling is the most common alternative to a cooling towerIt is particularly attractive when supplies of suitableBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.

comAgainst this, the capital costs of the actualIn order to choose correctly between the available cooling systems, it isFor example, a water cooled refrigerant condenser will, in general, condense theThus, the choice of system may be governed by more complex considerationsThe accurate estimation of the advantages of the available cooling systems willThe engineer will have to make the choice in manyShould water be available near the plant battery limits, in sufficientIf it will be necessary to use town's mains water, or other highly treatedBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comIn assessing the differenceIn many cases this is not aIn performing these comparisons it will be necessary to make an estimate of theManufacturers will normally be prepared toAlternatively, the engineer could perform a preliminary design, and obtain a costThis bypasses the step of designing theThere are some occasions when consideration should be given to factors otherAmbient air temperatures vary more than cooling tower water temperatures. IfSuch solutions are expensive, clumsy and notAlternatively, an indirect cooling systemSee also Clause 6 on Control. It is more economic to cool hot streams with air, and cooler streams with water. It. The extra pressure drop of the trim coolerOf course, if the process demands coolingIn this case, look at the possibility of cooling by water only, unless the processBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comWeb Site: www.GBHEnterprises.comACHEs are bulky, and produce noise and warm air.

Their siting should beThe total plot area can be estimated by the method given in Appendix A, or otherIt is usual to find a place for ACHEs without greatFinding a grade position for the ACHEs might be worth more than 15 dB in theA check on possible air recirculation within banks and between banks should beThe airflow pattern into an ACHE shows a high velocity near the edge of the inletThis is particularly trueAs a general rule, some warm air recirculation will occur withShould the air inlet be restricted, for instance byBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comOtherwise separate the banks by 15 m if on theThis will prevent recirculationDownwind of large buildings, where downdraughts are possible, the veryAs far as possible, avoid close proximity to sources of stray heat, such asThese points are illustrated in Figure 9. Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comIf they cannot be, theFor critical dutiesHowever, such tests areVarious site conditions may force the choice of air or water cooling.Environmental conditions may forbid the use of cooling towers orIf there is a shortage of suitable make-up water, water cooling may beAn excessively stringent noise requirement may force water cooling, (seeBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comWeb Site: www.GBHEnterprises.comNoise specifications fall into two classes:Limitations near the ACHE to protect the hearing of operators.Limitation at points remote from the plant, to protect the amenity ofThe actual specification of maximum permitted noise levels will vary from case toMachinery SectionBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.

comCommunity noise specifications can be very difficult to meet. A tight noiseGreat attentionA noise expert and an ACHE expertPlanning authorities sometimes impose a more stringent noise specification atAs ambient air temperatures are usually lower atThe size and hence cost of an air cooled heat exchanger is sensitive to theAmbient air dry bulb temperatures vary. For overseas locations, significantlyIn contrast, the wet bulb temperature,In selectingThis is discussed in more detail in sub clause 5.5. The minimum design temperature is important in considering control andBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comThis sub clause is intended to give a brief description of typical Air Cooled Heat. Exchangers and to explain the terminology for the benefit of those who are notThe process fluid flows through the tubeside of one or more bundles of tubes; theIn principle, there areFigure 10 shows the major parts of a typical air cooled heat exchanger. Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comThe central elements of an ACHE are the TUBES through which the process fluidThis is to counter theTubes are typically fromThe tubes are grouped in BUNDLES, typically 1-2 m wide. Within the bundle, theBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comDifferent forms of header are used, depending onACHE bundle can have either single pass process flow, with the process fluidUnlike shell and tube exchangers, it is common for the different passes to haveA typical arrangement for an air cooledBundles are usually mounted horizontally, but for condensers there may be aA large ACHE will require several bundles to provide the surface. Bundles areAir for cooling is assisted through the bundle by FANS.

Axial flow fans, giving aOn large units these fans are often 3-4 m in diameter;The width of a bay, the chosen tube lengthIn order to ensure reasonable airFigure 11). It is normal to have between one and three fans for each bay. OnSee sub clausePLENUM chamber. This may be a simple rectilinear box, as shown in Figure 10,The fan and plenum mayDRAUGHT arrangement, or below it, giving FORCED DRAUGHT (see subBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comIt is more usual, however, to control air flow, ifIn certain cases, especially in locationsThe inlet and exit headers on each bundle will have at least one connection forThe several inlets or outlets will be connected by MANIFOLDS. See sub clauseThe complete ACHE installation will include a support framework to mount itWeb Site: www.GBHEnterprises.comUnlike shell and tube exchangers, where the thermal and mechanical design areThe normal approach is to specify the required duty,Enterprises wish to place on the design. These will include layout constraints,Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comSee GBHE-PEG-HEA-504 for guidance on design margins for heat exchangers. The thermal duty will usually be specified by the process engineer, who shouldEnterprises Engineering Data Sheet. A design margin may be specified for several reasons:The section of plant may be required to run at instantaneous rates aboveDesigning for this condition does not represent a true design margin, asThe engineer may wish to make provision for future plant uprating. If it isIt is probable that an air cooled heat exchanger on a critical duty will be.

The physicalThe manufacturerFurther, theIt is generally advisable, for a criticalA thermal design margin (safety factor) may be provided in several differentIt is important thatThe engineer should be waryBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comThis sheet should be included, suitably annotated, in the plant manual, along withIf the extra surface is provided by increasing the number of tubes perIt will result in a more expensive unitIt is better to provideIt is not possibleSometimes a higher air temperature is specified for critical services thanAs a means of providing a design margin, this suffers from the sameIf this approach is used, and theAs the unitThis reduces the overall heat transfer coefficient, resulting in a largerThe manufacturer will seek toThe approach is useful when dealing with a manufacturer, as it means thatHowever, it is good. Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comIn many ways this is the most satisfactory form of safety margin, and itHowever, it suffers from the same drawback as does raising the design airAs a general rule, high heat transfer coefficients tend to be associated with highHowever, in general,The cost of pressureFor low pressure condensation duties, particularly vacuum condensers, it isFouling resistances specified frequently take no account of the effect of foulingAs the pressure drop for a single phase fluidBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.

comComparison of theIf so, the only solution is to makeThe specified ambient temperature is an important parameter affectingA rigorous examination of the effect of ambientThe best that can be hoped for is aIn general, the effect of too low a design air temperature will be aThe true cost of such turndownLenient Design (Non-critical duties). The chosen temperature is exceeded for approximately 450 hoursModerate Design (Normal duties). The chosen temperature is exceeded for approximately 150 hoursVery Safe Design (Critical duties only). The chosen temperature is exceeded for only 30 hours per year.Ideally, temperature frequency data should be obtained for the worksFailing this, the Meteorological. Offices maintain records for a number of locations throughout yourBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comAs a guide, the in-plant. The minimum expected air temperature should be specified, as this notWeb Site: www.GBHEnterprises.comAlthough within Europe most plants are sited at an altitude not farThe performance of a given air cooled heat exchanger willAlthough manufacturers of air cooled heat exchangers will generally have accessThe best way ofSee GBHE-PEG-HEA-500.The specification generally used for the purchase of GBHE recommended. ACHEs, is largely concerned with the mechanical specification of the heatThe Process Engineer should discuss this with the manufacturer, basedFor many duties, especially with lowBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.

comTube materials will normally be dictated by process considerations,Three fin materials are commonly used in fin tubes - aluminium, steel andAluminium:Aluminium has adequate corrosion resistance for most ACHESteel fins:They are, in someThey are also muchThe efforts made to improve air quality at these sites has beenCopper:The cost disadvantage ofBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comHowever, copper finned ACHEs haveThus aluminium finning is the almost invariable choice for process ACHEs. The choice of tube metal to which it is applied is determined by processThis has anThe aluminium therefore acts asThe result is that external corrosion ofThis will beIf aluminium tubes are used with aluminium fins, it is necessary to checkThe corrosion to be avoided is a general corrosion of the fins. UnprotectedAt less aggressiveAs explained inShould atmospheric corrosion occur, the corrosion product is bulky andIt will cause an increasedGenerally, there willBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comThere are many different varieties of finned tubing available. (See, forThis is the recommended form of tubing for process duties most typicallyThese finned tubes areThe resultant tubing is robust, with little likelihoodIt is sometimes suggested thatSome tubes submitted to the British Non-ferrous. Research Association for long term marine and industrial corrosion testsThere is a suspicion that preferential corrosionThere is no known evidence to supportThe remaining types of finned tubing are not generally recommended for processA strip of metal is tension wound onto the outside of the tube to give aIn the extreme, if the fin shouldBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.

comA particularly damaging form of corrosion occursThis makes an effectiveAlthough only indirectly concerned with corrosion, there is another point toThe result is that any interface thermal resistanceValues as high asIf the mill scale is removed, then the tube isSome McElroyThese are intended to giveSince there is no risk ofFintube can be formed by an extruding operation, rather like anIf an aluminium tube is threaded overHowever, noBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comElliptical tubing. The specification of rectangular steel fins galvanized onto elliptical tubingGEA claimed as the advantage for this type of tubing that the airsideGEA appear no longer to offer it asWeb Site: www.GBHEnterprises.comAlthough different dimensions may be used, the commonest form ofHowever, inSpecification of the type of fin, still holds. The temperature limits for theHowever, any proposal which is basedBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comThe clearance between the ACHE and grade, of one fan diameter, isWork by CMB Russell showed that obstructions in the fan discharge areS.14.1.6 should apply also to the fan discharge (particularly for inducedThe noise levels as specified, although they could be met, may result inThe specification of noise levels near the ACHE toShould there be a communityACHE bank is often below the background noise level.

In these conditions,The allowable SPL near theIt is probable that a lower noise level will be required at night than duringThe reduction in noiseIt is most unwise to operate a fan at a point near the stall region, andFans meeting theseThe requirement may affect the thermalThe effect of stall is much more severe with broad chord fans, than is theBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comWedge V-Belts and gearboxes are both disliked on site, owing to theirIt seems reasonable to recommend them for drive motors up to 30!kW.Figure 17 shows diagrammatically some of the header types used in. ACHEs. Should it be essential to avoid tubeside leakage of an ACHE,This permits radiography ofTube fixing will be by welding when leakage is feared, and, althoughAlthough plugs resist leakageA dummy tubesheet may beSee also sub clause 10.4 for further comments on header types. Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comWeb Site: www.GBHEnterprises.comThe manufacturer needs to be informed of the available space where theThe process engineer may have a preference for a forced or inducedThey are usually cheaper.The required power is lower than for an induced draught unit.The fans are closer to the ground and thus are easier to supportThe fan and drive are not exposed to the hot exit air.The bottom rows of tubes, which are those most prone to fouling,The plenum chamber protects the bundle from harsh weatherThere is less likelihood of air recirculation because of the higherIf the process fluid is a liquid, leaks from the bundle should not fallBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comHowever, work by Russell and Berryman of HTFS on ?

Particularly if the ACHE is a large unit, with multiple bundles, the arrangement ofIf not, then it is recommended that noAll sites without severe fouling, report that they are well able to cope with theIf serious fouling is expected, then the choice of direct air cooling for the plantIs water really not available for evaporativeRemember that the recommendations forShould direct air cooling be considered the correct choice, then the followingInduced draught ACHEs should be used in all cases where designParticular attention should be paid to giving good access to the bundlesThe fin pitch in the lower two rows should be limited, perhaps to 275The tube pitch should be such as to give at least Y ins (9 mm) betweenBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comThe fan selection should allow for a suitable margin to avoid stalling whenIn addition, one of the following may be specified:This is expensive, and willIt may have disadvantages of its own, and may beThis solution isAny ACHE design is a compromise between high fan power and a smaller andIf it is hoped to optimize theseThere are many ways of performing suchIt is essential to impress on the tenderer that the offers will in fact be penalizedUnless this is done, past experience will convince theBalance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance. Web Site: www.GBHEnterprises.comNow customize the name of a clipboard to store your clips. Select an overall heat transfer coefficient (U) from literature based on type of fluids. Select an air inlet temperature (t1) that is not exceeded during a certain percentage of time over the year (e.g. 95% of the time). Above steps are iterated till there is no change in air outlet temperature. Fan area per fan (FAPF) is calculated as following.

The noise is generally broad band, except for occasional narrow band noise produced by the motor or speed reducer, or by interaction between these sources and the structure. For efficient fans at moderate fan tip speeds, this noise is proportional to the third power of the fan blade tip speed and to the first power of the consumed fan horsepower. It is quite practical and usually economical to reduce the sound pressure level at 3 feet below an air-cooled heat exchanger to 85 dB(A); but, below 80 dB(A), noise from the drives predominates and special measures must be taken ( Hudson Products Corporation, 2007 ). View chapter Purchase book Read full chapter URL: Advances in dry cooling for concentrating solar thermal (CST) power plants K. Hooman,. H. Gurgenci, in Advances in Concentrating Solar Thermal Research and Technology, 2017 9.2.2 Dry cooling towers Dry cooling towers conduct heat transfer through air-cooled heat exchangers that separate the working fluid from the cooling air. Because there is no direct contact between the working fluid and the ambient air, there is no water loss in this system. Dry cooling towers have two basic types: direct and indirect systems. In a direct dry cooling tower, turbine exhaust steam is condensed directly through an air-cooled condenser (ACC). As shown in Fig. 9.4, the turbine exhaust flows directly into the tubes of ACC. A large-diameter piping is used at the turbine outlet to accommodate the relatively low steam densities (compared with water) and reduce the pressure drop through the route. The exhaust steam flows inside the tubes of ACC and is condensed by transferring the heat to the flowing air outside the surface of the heat exchanger. Figure 9.4. Direct dry cooling tower (commonly known as air-cooled condenser, ACC). The cooling water gains the heat in the condenser and is pumped back to the heat exchanger inside the cooling tower.

Air is introduced to flow across the exterior surface of the heat exchanger to cool the hot water inside the heat exchanger tubes. The cooled water inside the heat exchanger tubes is then pumped back to the condenser. The turbine exhaust is condensed by the circulating water rather by the ambient air directly; hence, it gets the name of indirect cooling. Figure 9.5. Schematic of indirect dry cooling tower (Kelvion Thermal Solutions). Increasing volumetric flow rate of air through heat exchangers improves the performance of the cooling system which ultimately depends on the air dry bulb temperature. For a CST power plant, the choice between wet and dry cooling systems involves a number of trade-offs including the availability and cost of water, environmental aspects, and the cost of electric power. Because CST power plants, in general, are located in arid areas, water conservation is a major factor favoring for dry cooling towers. Although dry cooling has advantages for water conservation and environmental protection, it suffers from lower efficiency when ambient air temperature is high. Thus, new technologies in increasing CST power plant production during high ambient temperatures are required. View chapter Purchase book Read full chapter URL: Physical Property of Liquids and Gases A. Kayode Coker, in Fortran Programs for Chemical Process Design, Analysis, and Simulation, 1995 Heat Capacities of Gases The heat capacity of gases is essential for some process engineering design, e.g., for air-cooled heat exchanger and for gas-phase chemical reactions. Here, in the latter case the heat capacities, C p 0, for gases are required to determine the heat necessary to bring the chemical compound increase to the reaction temperature. C p 0 is also used in the rating of heat exchangers and energy balance computations. The heat capacity of a mixture of gases may be found from the heat capacities of the individual components contained in the mixtures.