Heat double pipe

Minimum Area. The limit of minimum network area is presented in References 2 and 3. If idealized double-pipe exchangers are used, a heat-exchange network having minimum area can quickly be developed for any In the limiting case, where all heat-transfer coefficients are assumed to be equal, the area for this network can easily be obtained from the composite streams by... 

Reaction times can be as short as 10 minutes in a continuous flow reactor (1). In a typical batch cycle, the slurry is heated to the reaction temperature and held for up to 24 hours, although hold times can be less than an hour for many processes. After reaction is complete, the material is cooled, either by batch cooling or by pumping the product slurry through a double-pipe heat exchanger. Once the temperature is reduced below approximately 100°C, the slurry can be released through a pressure letdown system to ambient pressure. The product is then recovered by filtration (qv). A series of wash steps may be required to remove any salts that are formed as by-products. The clean filter cake is then dried in a tray or tunnel dryer or reslurried with water and spray dried. 

Double-pipe exchangers are often piped in complex series-parallel arrangements on both sides. The MTD to be used has been derived for some of these arrangements and is reported in Kern (Process Heat Transfer, McGraw-Hill, New York, 1950). More complex cases may require trial-and-error balancing of the heat loads ana rate equations for subsections or even for individual exchangers in the bank. 

Double-Pipe Scrapea-Surface Crystallizer This type of equipment consists of a double-pipe heat exchanger with an internal agitator fitted with spring-loaded scrapers that wipe the wall of the inner pipe. The cooling hquid passes between the pipes, this annulus being dimensioned to permit reasonable shell-side velocities. The scrapers prevent the buildup of solids and maintain a good film coefficient of heat transfer. The equipment can be operated in a continuous or in a recirculating batch manner. 

For flow parallel to tubes or in an annular space, e.g. a double-pipe heat exchanger, use... 

Heat Exchanger - Shell and tube and double pipe exchangers, where the cooler side can be blocked in full of liquid while the hot side fluid flow continues, must be protected by either ... 

Heat exchangers used in gas production facilities are shell-and-tube, double-pipe, plate-and-frame, bath-type, forced-air, or direct-fired. In this chapter we will discuss the basic concepts for sizing and selecting heat exchangers. This is just a brief overview of this complex subject and is meant to provide the reader with a basis upon which to discuss specific sizing and selection details with heat exchange experts in engineering companies and with vendors. 

Double-pipe exchangers - the simplest type, used for cooling ind heating. 

One of the simplest and cheapest types of heat exchanger is the concentric pipe arrangement known as the double-pipe heat exchanger. Such equipment can be made up from standard fittings and is useful where only a small heal transfer area is required. Several units can be connected in series to extend the capacity. ... 

Double-pipe exchangers-the simplest type with concentric pipe arrangement used for cooling and heating several units can be connected in series to extend their capacity. ... 

Double Pipe Finned Tube Heat Exchangers... 

For a double pipe exchanger (one finned tube in each of two shells), see Figure 10-4A, the heat flow resistances are ... 

Used by permission How to Design Double-Pipe Finned Tube Heat Exchangers. Brown Fintube Co., A Koch Engineering Co., Houston, Texas. 

The outer and inner tubes extend from separate stationary tube sheets. The process fluid is heated or cooled by heat transfer to/from the outer tube s outside surface. The overall heat transfer coefficient for the O.D. of the inner tube is found in the same manner as for the double-pipe exchanger. The equivalent diameter of the annulus uses the perimeter of the O.D. of the inner tube and the I.D. of the inner tube. Kem presents calculation details. 

Heat exchangers for liquids will be double pipe, shell-and-tube and plates (see Figures 6.3, 6.4 and 17.1). Waste fluids may be contaminated by the process, and heat exchangers for such fluids must be cleanable, and kept clean. 

The whole set-up for partial oxidation comprises a micro mixer for safe handling of explosive mixtures downstream (flame-arrestor effect), a micro heat exchanger for pre-heating reactant gases, the pressure vessel with the monolith reactor, a double-pipe heat exchanger for product gas cooling and a pneumatic pressure control valve to allow operation at elevated pressure [3]. 

Figure 6.4a, b. Gasketed plate and frame and double pipe heat exchangers, Time base mid-2004... 

Recovery column condenser double-pipe, heat transfer area 1.5 m2, design pressure 2 bar, materials carbon steel. 

Solvent cooler double pipe exchanger, heat transfer area 2 m2, materials stainless steel. 

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