HEAT EXCHANGERS. Heat Exchangers are available in 2 basics designs: 1. Conventional Coil Type Condensers. 2. Shell & Tube Type.

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1 The overall heat transfer co-efficient of Borosilicate glass equipment is comparatively favourable with many alternative materials because of its smooth surface which improves the thermal coefficient & reuce the tenency of fouling. Heat Exchangers are available in basics esigns: 1. Conventional Coil Type Conensers.. Shell & Tube Type. 34

2 SHE AND TUBE INTRODUCTION Shell & tube heat exchangers offer large surface area in combination with efficient heat transfer an compactness. These are wiely use in inustries for various uties like cooling, heating, conensation, evaporation etc. GOE are the pioneers in the fiel of glass shell an tube heat exchangers in Inia an their prouct has a wie market acceptability. SAIENT FEATURES 1. Universal corrosion resistance an excellent alternative to expensive MOCs like graphite, hastelloy, copper titanium, tantalum an other exotic metals.. Excellent heat transfer as fouling oes not occur on smooth glass surfaces. 3. Flexibility of installation vertical / horizontal. 4. Easy replacement of tubes for repair an cleaning. 5. Available in wie range of HTAs. 6. Ease of installation ue to light weight. 7. Economical. 8. Suitable for applications where large HTAs are require in limite space. ADVANTAGES OVER CONVENTIONA COI TYPE (1) The overall heat transfer coefficient in shell an tube heat exchanger is about 3 times higher than in coil type heat exchanger. () The pressure rop in shell an tube heat exchanger is minimal compare to -3 kg/cm in coil sie of coil type heat exchanger. (3) For requirement of higher heat transfer areas shell an tube heat exchanger is the only alternative. HEADER CONSTRUCTION FEATURES The glass tubes are seale iniviually into PTFE tube sheet with special PTFE sockets an packing. This unique ferrule type sealing arrangement permits easy replacement an cleaning of tubes. Baffles on shell sie ensure improve heat transfer by increase turbulance. Further etails of construction can be seen in the iagram. - Mae from SCHOTT DURAN. - Joint less tubes offer better pressure rating. SOCKET TUBE SHEET PACKING GASS TUBE TIE ROD BAFFES SHE TYPE Three basic versions * are available : Material Of Construction Moel Shell Tube Heaer Duty RGG Glass Glass Glass For heat transfer between two agressive meia. RGM Glass Glass Steel/ FRP For heat transfer between agressive meia in shell & nonaggressive meia in tubes. RMG Steel/FRP Glass Glass For heat transfer between aggressive meia in tubes & non-aggressive meia in shell. NEW: Also Available with Graphite Tube * GOE provies assistance to clients for selecting the right moel for specific uty. 35

3 DIMENSIONA SPECIFICATIONS Cat. Ref. RGG/RMG 6/3 6/4 6/5 6/6 9/6 9/8 9/10 9/1 1/1 1/16 1/1 1/5 Area (m ) H H T No. of Tubes No. of Baffles H 3 H1 4 T RGG T 4 3 H H1 6 TUBE BUNDE RGM RANGE OF APPICATIONS 0 0 Permissible temperature range for both shell & tube sies - 40 C to 150 C. 0 Maximum permissible temperature ifference between shell & tube sies 10 C. All sizes & moels are suitable for full vacuum on both sie. Maximum limiting pressures are tabulate here below : Maximum Permissible Pressure Range, Kg/cm (g) Moel Sie RGG Shell Tube RGM Shell TUbe RMG Shell Tube The above ranges of application are amissible limiting values. For each specific case GOE recommens the amissible operating ata base on the relations between pressure an temperature, size an moel.

4 PERFORMANCE & DESIGN DATA The particular avantage of shell & tube heat exchanger is high heat transfer performance. The relation between heat transfer an velocity of flow can be easily seen in the iagram. On receipt of the operating ata from client the most favourable shell an tube heat exchanger is selecte. This accurate esign combine with most reliable quality assurance ensure economy an operational reliability for the user. For approximate sizing some typical heat transfer coefficients are given here below : K Value in W / M K Cooling Water Cooling Brine 300 U-Values Meia use kcal/m hr k W/m k Steam water Conensation Water-Water Cooling Water-air Cooling Coolant Velocity in M/Sec. GRAPHITE TUBE HEAT EXCHANGER 37

5 CONDENSERS Conensers are use for conensation of vapours an cooling of liquis. Conensers are mae by fusing number of parallel coils in a glass shell. C o i l s a re m a e i n i ffe re nt iameters using tubes of ifferent bores. The average co-efficient of heat transfer in coil conenser is consiere as- o Conensation Kcal/m,hr, C appx. o Cooling Kcal/m,hr, C appx. TYPE-B 1 TYPE-A 1 Free Max. Actual Cross Coolant Jacket Cat. / H.T.A. Area Rate Cap. Ref. 1 Type m Cm Kg/hr. itre HE3/3.5* A HE4/5* A HE4/6* A HE6/ B HE6/15* B HE9/5* B HE1/ B HE1/40* B HE16/ B HE16/ B HE18/ C HE18/ C HE4/ C TYPE-C 1 Precautions to be taken in use of conensers - Vapours shoul be passe through shell only. - Maximum pressure of coolant shoul be.7 bars. - Aequate flow of coolant shoul be use. - Steam shoul not be use in coils. - Coolant shoul not be heate to boiling point. - Coolant control valve shoul be turne slowly. - Coolant shoul be allowe to rain freely. - Brine can be use in coils in a close circuit. - Water main shoul be connecte with flexible hose. - Ensure no freezing of water remaining in the coils. - Conensers shoul be mounte vertically only. - Conensers can be mounte in series to provie larger surface area. METHODS OF USE Vapours from bottom This metho is simple to install over a reactor. However this results in conensate returning substantially at its conensing temperature. In this metho care must be taken that conensate is not excessive that it can lea to "logging" the coils an create back pressure in the system. Generally a reflux ivier is use below the conenser to take out the istillate. Vapour Vapour Vapours from top This metho prouce a cool conensate using the entire cooling surface area. This metho shoul be use where the conensate can lea to "logging" of coils. Conensate 38 * marke items are available fast.

6 BOIERS Boilers are use for vaporization of liquis by passing the steam in the coils. Boilers are mae by fusing number of parallel coils in a glass shell. In Boilers, coils are esigne to provie bigger cross section in the shell sie as compare to conensers. o The average heat transfer in Boilers is consiere as 350 Kcal/m,hr, C at a steam pressure of 3.5 bar. Free Actual Cross Jacket Cat. H.T.A. Area Cap. Ref. 1 Type m Cm itre HEB A HEB4/ B HEB A HEB6/ B HEB A HEB9/ B HEB1/ B HEB - TYPE-A 1 HEB - TYPE-B Notes on use of Boilers : - Steam shoul be passe in the coils at a maximum pressure of 3.5 bar which is equivalent O to a temperature of 147 C. O - For higher temperature (maximum upto 00 C) heat transfer fluis can be passe in the coils. - Col liquis - Col liquis shoul be preheate for better results. - Boilers shoul bemounte in an external circulatory loop (as shown in figure) an not irect at the bottom of flask or column - Uner certain circumstances, boilers can be mounte in series to provie larger heat transfer area. ANGED HOSE CONNECTOR ASSEMBIES Metal / Plastic angle hose connector assemblies are available to connect the flexible hose to the conensers. These are provie with a mating flange, a rubber gasket an nut bolts. Cat.Ref. PMC IMMERSIONS Immersion heat exchangers are use to control exothermic reaction in glass vessels. They can be use with vessels having wier bottom outlet (type VSR an VSE). These are provie with a central hole through the coil battery so that a special, extene type, stirrer can be fitte which extens to the bottom of heat exchanger an provie through action. In most applications, cooling water is use in coils (max. pressure.7 bar g.), but they can also be use with steam (max. pressure 3.5 bar g.). In latter case the coils must be completely immerse in liqui. Immersions are not recommene for use with proucts which have a tenency to crystalise. 1 Cat. Actual Ref. 1 m H.T.A. HEM HEM HEM

7 PRODUCT COOERS Prouct coolers are use for cooling of liquis, typically, for the cooling of istillates from the istillation columns. Unlike coil conensers, in prouct coolers, prouct travels through the coil battery an coolant through shell. This provies more resient time to the prouct to be coole. For irect connection with istillate lines, all the prouct coolers are provie with 5 connections. Actual Cat.Ref. HTA m Type HEF1/1* A HEF1/* A HEF1/3.5* A HEF HEF HEF1/5* A HEF1/ B HEF1/ B TYPE - A TYPE - B UTIITY CONNECTION FOR CONDENSER When installing coil type heat exchangers appropriate precautions shoul be taken. The main points to be taken into account when planning to use these items as coolers are (See also flow chart below). UTIITY OUTET FEXIBE HOSE PRESSURE GAUGE NON RETURN VAVE VAVE CONTRO VAVE DRAIN FEXIBE HOSE UTIITY RETURN UTIITY SUPPY 40