Cyclone separators Design

FIG. 23-53 Cyclone separator design details. (Guidelines for Pressure Relief and Effluent Handling Systems, Center for Chemical Frocess Safely (CCPS) of the American Institute of Chemical Engineers (AIChE) copyright 1988 AIChE and reproduced with permission.). 

The sizing procedure is presented in Guidelines for Pressure Relief and Effluent Handling Systems (AIChE-CCPS, 1998). Figure 23-53 shows the dimensions of a cyclone separator designed in accordance with this procedure. If liquid is continuously drained from the cyclone to a separate accumulator, a vortex breaker and false bottom should be used (Fig. 23-53, view BB). 

Centrifugal Separation Centrifugal force can be utilized to enhance particle collection to several hundredfold that of gravity. The design of cyclone separators for dust removal is treated in detail in Sec. 17 under Gas-Solids Separations, and typical cyclone designs are shown in Fig. 17-43. Dimension ratios for one family of cyclones are given in Fig. 17-36. Cyclones, if carefully designed, can be more efficient on hquids than on solids since liquids coalesce on capture and are easy to drain from the unit. However, some precautions not needed for solid cyclones are necessary to prevent reentrainment. 

Cyclone Separator with Integral Catch Tank This type of containment system, depicted in Fig. 26-19, is similar to the ore-mentioned type, except that the knockout drum and catch tank are combined in one vessel shell. This design is used when the vapor rate is quite high so that the knockout drum diameter is large. 

General In comparison with design information on blowdown drums and cyclone separators, there is very httle information in the open technical hterature on the design of quench tanks in the Chernies industry. What is available deSs with the design of quench tanks (Sso called suppression pools) for condensation of steam or steam-water mixtures from nuclear reactor safety vSves. Information and criteria from quench tanks in the nuclear industry can be used for the design of quench tanks in the chemicS industry. There have been sev-... 

For additional details on the design of blowdown drums, cyclone separators, and quench tanks, such as mechanical design, thrust forces, ancillary equipment, and safety considerations, refer to the books and articles listed in the General References. 

References 15 through 23 provide additional information on cyclone separators and the design and scale-up principles. 

If an interior centrifugal (cyclone) separator is used, the inlet nozzle size should be the same size as the pipe. If the internal design requires... 

Six-tenths factor, 47 Yearly cost indices, 47 Critical flow, safety-relief, 438 Back pressure, 440 Sonic flow, 438 Critical flow, see Sonic Cyclone separators, 259-269 Design, 260-265 Efficiency chart, 263 Hydroclones, 265-267 Pressure drop, 263, 264 Scrubber, 269 Webre design, 265 Deflagration venting nomographs,... 

In modem boilers, both FT steam spaces and WT steam drums incorporate various devices to promote the effective separation of steam from water and the production of dry steam. These devices include horizontal separators and baffle plates in the steam/water space, and chevron driers, cyclone separators, and secondary steam scrubbers in the steam space. Older or simpler boiler designs with steam release velocities of below 3 ft/s (0.9 m/s) may rely solely on the natural separation of steam from water. 

Cyclone separators can be designed for 95% collection of 5 pirn particles, but usually only droplets greater than 50 pirn need be removed. 

Spray dryers are normally used for liquid and dilute slurry feeds, but can be designed to handle any material that can be pumped. The material to be dried is atomised in a nozzle, or by a disc-type atomiser, positioned at the top of a vertical cylindrical vessel. Hot air flows up the vessel (in some designs downward) and conveys and dries the droplets. The liquid vaporises rapidly from the droplet surface and open, porous particles are formed. The dried particles are removed in a cyclone separator or bag filter. 

Cyclone separators are also frequently used for gas-liquid separation. They can be designed using the same methods for gas-solids cyclones. The inlet velocity should be kept below 30 m/s to avoid pick-up of liquid form the cyclone surfaces. 

Stairmand, C. J. (1951) Trans. Inst. Chem. Eng. 29, 356. Design and performance of cyclone separators. STRAUSS, N. (1975) Industrial Gas Cleaning (Pergamon). 

This will be a positive-pressure system, since each dryer will feed 5 extruders. It will be designed to run at the same rate as each dryer, 9,210 lb P.S./hr. The vertical rise is 30 ft and the maximum distance traveled is 130 ft. Because powder is being conveyed a cyclone separator will be specified for each of the extruders. The blowers should be designed to have an LHP of 7.2 and a BHP of 8.4. The power required to operate both is 12.6 kw. 

Molerus, O., and Gltickler, M., Development of a Cyclone Separator with New Design, Powder Tech., 86 37 (1996)... 

Stairmand, C. J., The Design and Performance of Cyclone Separators, Trans. Instn. of Chem. Engrs., 29 356ff, London (1951)... 

The papers in this section represent the theory and current industry practices in the separation process and in separator design. Because separation is such a basic requirement for the oil and gas industry, a wealth of information has been published concerning the process and the various design techniques used in the manufacture of separation equipment. Some of these techniques are proprietary, however, and the details of the design are not readily available. For instance. British Petroleum has done considerable design and testing of cyclone-type separation equipment in recent years with the objective of miniaturizing the equipment for use on offshore platforms. For further details on this and other proprietary equipment, one must contact the manufacturer or licensee of the equipment. 

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