FOR THE PETROLEUM AND RELATED INDUSTRIES

Transcription

1 H E A T E X C H A N G E R S BULLETIN NO. TIS-111A PRIME SURFACE PLATE & FRAME ALL-WELDED PLATE FOR THE PETROLEUM AND RELATED INDUSTRIES THE heat transfer people H E A T E X C H A N G E R S

2 2 TRANTER BRINGS EFFICIENCY AND RELIABILITY TO THE PETROLEUM INDUSTRY Excellent efficiency and flexibility...optimum heat transfer... minimal maintenance...these are critical needs today in the petroleum industry. Tranter provides these benefits and more, with PLATECOIL, SUPERCHANGER and MAX- CHANGER heat exchangers that are standards for the industry. SUPERCHANGER plate and frame units are the best choice because they give you: (1) higher U values typically 3 to 5 times greater than shell-and-tube; (2) a unique turbulent flow design resulting in lower fouling; (3) closer temperature approach capability of less than 2 F, compared to the typical 10 F or higher with shell-andtube; (4) space savings of 50% to 90% over shell-andtube; (5) expandability and easy servicing, and (6) immediate availability, since they are made in the U.S. PLATECOIL PRIME SURFACE HEAT EXCHANGERS A multitude of design configurations and over 300 different sizes make PLATECOIL units ideally suited for a variety of applications in the petroleum industry. They offer versatility in providing the heating and/or cooling required for various applications in the industry. PLATECOIL units are perhaps best known as immersiontype, in-tank or as clamp-on heaters for maintaining product temperatures in tanks. Their use goes far beyond these applications, however, and includes designs for custom-engineered processing equipment. PLATECOIL units can be fabricated from most weldable metals including carbon steel, stainless steel, titanium, Monel, nickel and various special corrosion-resistant alloys. Surface finishes are available to minimize fouling and reduce maintenance. SUPERCHANGER PLATE & FRAME MAXCHANGER ALL-WELDED PLATE Where space is at a premium, or gasket limitations prevent the use of a SUPERCHANGER unit, the compact all-welded MAXCHANGER unit may be the best solution to many petroleum applications. Plate and frame heat exchangers provide a more efficient and cost effective means of heat transfer than old, traditional shell-and-tube exchangers. This is particularly true in the petroleum industry. NOTE: THE DIAGRAMS SHOWN ARE PURPOSELY BRIEF: NO ATTEMPT HAS BEEN MADE TO SHOW ALL THE VALVES, PUMPS, CONTROLS, ETC., THAT MAY BE REQUIRED. IN MOST SYSTEMS, ALL PIPING ACTUALLY IS FROM THE SUPERCHANGER FIXED FRAME. THIS FACILITATES OPENING THE UNITS, WHEN REQUIRED, WITHOUT DISASSEMBLING PIPING.

3 3 TYPICAL PETROLEUM INDUSTRY APPLICATIONS HEATING CRUDE OIL TO REMOVE SAND AND WATER Emulsions of viscous crude or water and crude which contain sand require special treatment. Heating the crude with steam or glycol using SUPERCHANGER or PLATECOIL heat exchangers lowers the viscosity so that the sand and water will settle out in large knock-out tanks. The SUPERCHANGER units have the advantage of high U values for line heating. The PLATECOIL units add heat to the unagitated oil in the large tanks while settling out takes place. 1 HEAT RECOVERY FROM PRODUCED WATER When crude is heated, as in schematic #1, hot produced water is discharged from the treater. This hot water is a valuable source of energy, and a SUPERCHANGER unit recovers a large percentage of the available Btu s. It provides an ideal means of preheating boiler feed water. Other uses may be employed in some cases. At times the produced water is further heated by use of a SUPERCHANGER unit using steam. It is then injected directly into the wells. 2 HEAT RECOVERY FROM DRY CRUDE TO PREHEAT WET CRUDE This is similar to application #1 in that cold, wet crude from offshore wells, etc., is being heated. In this instance, heat recovery is part of the process. The hot, dry crude from the treater generally requires cooling anyway, so its heat is used to preheat the cold, wet incoming raw crude. SUPERCHANGER and PLATECOIL units are ideal for the individual duties shown. 3 COOLING HOT CRUDE WITH SEA WATER Some crude oil is hot as it comes from the wells. Cooling usually is required to lower its temperature below the vapor pressure of methane and other volatile gases for safety reasons. SUPERCHANGER units with titanium plates using sea water as a heat sink accomplish this cooling duty very efficiently. 4

4 4 PLATECOIL REGENERATORS FOR NATURAL GAS GLYCOL DEHYDRATORS 60N two-circuit PLATECOIL units are regularly used for heat exchange between glycol streams in natural gas dehydrators. As noted in the schematic, the rich glycol absorbs moisture from the gas and then must be heated to drive off the moisture. Once this has been accomplished, the now-rich glycol requires cooling. The 60N PLATECOIL unit performs this interchange very effectively. Thousands are in use. HEAT RECOVERY AND COOLING IN NATURAL GAS CLEANING PROCESSES The cleaning of natural gas involves heat exchange for which SUPERCHANGER PHE s are ideal because of their efficiency and compactness. The very close temperature approach, which is readily obtained with SUPERCHANGER units, can accomplish 90%-plus heat recovery from the lean to rich amine. The space requirements, surface area and cost of SUPERCHANGER units are far less than would be necessary for shell-and-tube. The process works equally well with sulfinol. REFINERY WASTE TREATMENT PROCESS The treatment of waste products for pollution control purposes at refineries requires heated tanks. PLATECOIL exchangers, as shown in the schematic, are versatile products for these requirements. Steam is used to heat the waste mixture to lower its viscosity to facilitate the settling out of solids. Large surface areas, as required, can be provided by a combination of internal and external PLATECOIL units. This also permits easy zoning of the heating surface STORAGE TANK HEATING Refineries and tank farms usually handle certain products which require heated tanks. PLATECOIL units, installed internally as suction heaters for warming material being pumped from the vessel, are regularly used. PLATECOIL heaters are also clamped on externally, allowing total accessibility. When heating sensitive lube oil, the PLATECOIL units are attached with an air gap between them and the tank wall so that steam can be used without overheating the product. 8

5 5 TYPICAL PLATECOIL AND SUPERCHANGER UNITS IN PETROLEUM AND RELATED INDUSTRY APPLICATIONS A. B. C. A typical duty for SUPERCHANGER units in the oil fields involves steam for heating crude oil to 180 F to break the emulsion and allow sand to settle out. See schematic #1. SUPERCHANGER units are ideally suited for heat recovery due to their close temperature approach capabilities. The unit shown is in the oil field. See schematic #2. Hundreds of PLATECOIL units are in service as regenerators for natural gas dehydrators. Two circuit style 60N PLATECOIL exchangers are used. See schematic #5. D. E. F. Schematic #6 covers amine-to-amine exchange in natural gas cleaning operations. This is an excellent application for SUPERCHANGER units. Clamp-on PLATECOIL units have been used for many years to maintain temperature in storage tanks. They are usually covered with insulation. See schematic #8. Large petroleum tanks are heated efficiently by internal PLATECOIL units in various arrangements. Schematics #7 and #8 illustrate common installations. G. H. I. SUPERCHANGER units are used in oil fields for heat recovery applications where hot produced water is used to preheat feed water to a steam generator. See schematic #2. The steam is then injected into the well for tertiary recovery. Spherical storage tanks for various natural gas and petroleum products sometimes require heating, particularly in northern climates. Clamp-on PLATECOIL units provide a very practical heater for both new and existing tanks. PLATECOIL units in large storage tanks are installed in various arrangements. When there is a minimum of product movement from pumping, very little structural reinforcement of the PLATECOIL unit is needed. SUPERCHANGER units are available on a 90-day, no-charge basis for on-site testing and evaluation. Contact your Tranter representative for information on the SUPERCHANGER trial unit policy.

6 6 SUPERCHANGER OUTPERFORMS SHELL-AND-TUBE SUPERCHANGER heat exchangers require much less space than shell-and-tube units. They can pack greater than 20,000 sq. ft. of super efficient heat transfer surface in a single unit with flow rates up to 25,400 gpm. They provide greater flexibility; are more easily cleaned; experience much less fouling; have no interleakage; are lighter in weight; and cost less. Most importantly, however, SUPERCHANGER units do a more efficient job of transferring heat in most applications, due in large measure to the turbulent flow created by the corrugated patterns of their plates. For a side-by-side comparison between SUPERCHANGER plate and frame heat exchangers and shell-and-tube exchangers, the charts below show the difference in dimensions and comparative performance data for two units in an identical application. PLATE AND FRAME HEAT EXCHANGER High efficiency U values 3 to 5 times greater than shell-and-tube; often greater than 1,500 Btu/ft. 2 hr. F Uses only 10% to 50% of shell-and-tube space Easy disassembly just loosen bolts Lower cost when stainless steel or higher grade of material is required Low fouling due to corrugations and inherent turbulence Variable heat transfer surface plates easily added or removed Low weight typically 1/6th of shell-and-tube Intermix between fluids not likely due to gasket design Inspection simply disassemble and inspect Excellent chemical cleaning due to corrugations/turbulence Maximum viscosity 30,000 cps Nominal Pressure drop low to medium Practically no heat loss no insulation required Can be designed for less than 2 F temperature approach with more than 90% heat recovery attainable Computer custom-designed sizing per application Low internal volume 10% to 20% of shell-and-tube Multiple duties possible with connecting frames SHELL-AND-TUBE HEAT EXCHANGER Low efficiency Needs twice as much space to pull tube bundle Complex disassembly tube bundle must be pulled Higher cost except in all carbon steel or carbon steel/copper construction High fouling due to circular cross-section and channeling 3 to 10 times greater Fixed surface only High weight up to 6 times that of plate and frame Fluids can intermix, both at welds and at tube sheet Inspection difficult must usually pull tube bundle Satisfactory chemical cleaning but must be cautious of dead spots Maximum viscosity 10,000 cps Pressure drop low to medium Great amount of heat loss insulation required Typically only a 5 F to 10 F minimum temperature approach can be achieved Computer designed, but must always be oversized to be safe Very high internal volume One unit required for each duty TYPICAL UNITS DESIGNED FOR THE SAME HEAT TRANSFER CONDITIONS ITEM SUPERCHANGER SHELL-AND-TUBE Surface Area 1,000 sq. ft. 3,000 sq. ft. Total Length Required Width 32 Diameter 30 Diameter Height Gross Volume 18 ft ft. 3 Net Weight 1,600 lbs. 6,000 lbs. Plate and frame heat exchangers take as little as one-tenth the space required for shell-and-tube exchangers, particularly when considering the space required for tube removal. DOTTED LINE REPRESENTS SPACE REQUIRED FOR TUBE REMOVAL REPRESENTED BY: For further information on PLATECOIL prime surface, SUPERCHANGER plate and frame and MAXCHANGER allwelded plate heat exchangers, contact: TRANTER, inc., Texas Division P.O. Box 2289 Wichita Falls, Texas (940) Fax: (940) THE heat transfer people 10M/398/ Printed in U.S.A TRANTER, inc.