Packing ceramic

Column tray parts or ceramic packing lodged in the impeller eye. 

Next, to determine packed column height use Table 9 for distillation HETP values, leaning tow ards the high side of the range for studies. For use of Kqa values see Section A—Absorbers. Bed height per packed bed runs up to 20-30 ft for metal or ceramic packings, but plastic packing is usually limited to 24 ft. 

Packing material can be plastic, metal, or ceramic. Packing efficiencies can be expressed as HETP (height equivalent to a theoretical plate). 

Figure 9-46. Physical property corrections for liquid hold-up for ceramic packing and carbon packing (as noted). Reproduced by permission of A/.C/r.E. Jour., Shulman, H. L., Wells, N., Ullrich, C. F., and Proulx, A. Z., V. 1, No. 2 (1955) p. 259 all rights reserved.

Figure 9-83. Ammonia-air-water absorption data of Wen, with ceramic packing. Used by permission of Chin-Yung, thesis. West Virginia University (1953).

If the columns must be packed dry, for instance to avoid contamination of process fluids with water, the packing can be lowered into the column in buckets or other containers. Ceramic packings should not be dropped from a height of more than half a metre. 

Metal and ceramic packings tend to remain wetted with the... 

The main factors favoring packed columns are (1) very corrosive applications, where plastic or ceramic packings are favored over trays, which are almost always constructed of metal (2) low pressure drop requirement, which is easier to achieve with packings than with trays (3) small-diameter columns, because trays require access for inspection and maintenance and (4) foaming systems, which are easier to handle in packed towers. 

The scrubber was a small vertical vessel about 28 inches (71 cm) in diameter and over 12 ft. (3.7 m) high and contained ceramic packing. This flat-top scrubber had a 4-inch (6 cm) hole that served as a vent. This vent allowed air to escape the system during the filling operation and allowed air to enter to displace the volume of acid periodically pumped to the process with a 50 GPM (11.4 m3/hr) pump. 

Finally, it should be mentioned that some thermal cracking on the ceramic packing material was observed at temperatures above 850°C. Whenever such an effect was detected, an attempt was made to correct for it in the coking data. A typical value for an experimental run at 810°C for 160 minutes was 35 mg coke on 5 gram of reforming catalyst, or about 0.7 percent by weight. 

Flsxeraffilc (Fig. 6.11 j). Flexeramic has crimps with round apexes and smooth, unperforated surfaces. This ceramic packing is available from Koch Engineering Company, Inc. 

Industrial reactors for catalytic incineration of VOCs contain ceramic or another inert packing material on the boundaries of the catalyst bed [9, 26]. In such reactors, the temperature after the inert ceramic packing can be estimated by the almost linear expression... 

The tendency in ceramic packing is towards high surface area, low gas flow resistance perforated saddles. These saddles give rapid dehydration with low resistance to gas flow. 

Related Calculations. With ceramic packing, the height of a single bed is, for structural reasons, frequently restricted to no more than 20 ft (—6 m). 

Packing diameter, in Hog f°r plastic packing, ft Hqq for ceramic packing, ft... 

Continue the illustration from step 2. Assume that the required cleanup is in fact 90 percent, that 1-5-in ceramic packing is to be used, and that a safety factor of 1.4 is to be used in the height calculation. Then the estimated height equals (safety factor)(Nog)(Hog), i-e-> (1.4)(4.61)(2.5), or 16 ft (4.9 m). 

Related Calculations. Apart from the rule of thumb concerning superficial velocity (see step 1), be aware of similar guidelines that pertain to mass flow rate through the absorption tower. For plastic packing, the liquid and gas flow rates are both typically around 1500 to 2000 lb/h per square foot of tower cross-sectional area for ceramic packing, the corresponding range is about 500 to 1000 lb/h. 

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