Stripper columns

When the recycle soot in the feedstock is too viscous to be pumped at temperatures below 93°C, the water—carbon slurry is first contacted with naphtha carbon—naphtha agglomerates are removed from the water slurry and mixed with additional naphtha. The resultant carbon—naphtha mixture is combined with the hot gasification feedstock which may be as viscous as deasphalter pitch. The feedstock carbon—naphtha mixture is heated and flashed, and then fed to a naphtha stripper where naphtha is recovered for recycle to the carbon—water separation step. The carbon remains dispersed in the hot feedstock leaving the bottom of the naphtha stripper column and is recycled to the gasification reactor. 

The second Hquefaction process is carried out at temperatures from 261 to 296 K, with Hquefaction pressures of about 1600—2400 kPa (16—24 atm). The compressed gas is precooled to 277 to 300 K, water and entrained oil are separated, and the gas is then dehydrated ia an activated alumina, bauxite, or siHca gel drier, and flows to a refrigerant-cooled condenser (see Drying agents). The Hquid is then distilled ia a stripper column to remove noncombustible impurities. Liquid carbon dioxide is stored and transported at ambient temperature ia cylinders containing up to 22.7 kg. Larger quantities are stored ia refrigerated iasulated tanks maintained at 255 K and 2070 kPa (20 atm), and transported ia iasulated tank tmcks and tank rail cars. 

FIG. 11 Production of linear olefins from linear paraffins. AC, adsorbent chamber EC, extract column GLS, gas-liquid separator H, heater Rx, reactor RC raffinate column ST, stripper column LE, light end. (From Ref. 10.)... 

The excess water is removed in a stripper column. The other three pieces of hardware in Figure 10-5—vacuum columns—are used to recycle the EO and to clean up the EG by splitting out the heavier glycol by-products. 

The stainless steel stripper column stood about 82 ft. (25 m) tall, which included a column skirt base of about 15 ft. (4.6 m) tall. The stripper collapsed in the lower 9-ft. diameter (2.7 m) section just below the conical transition section that tapered down to connect with the upper 5A ft. (1.7 m) diameter section. The vessel was designed to operate about 5 psig (34.5 kPa gauge) and was mechanically rated for about 25 psig (173 kPa gauge). 

Figure 3-7 A close-up of a collapsed stripper column. Courtesy of Guido DeJesus.

The best-known presentations are by Tomich (32), Holland (8), and Orbach et al. (33). These vary in their choice of Newton-Raphson equations and independent variables and each may solve a different range of columns, These methods have been shown to work well for wide-boiling mixtures including refinery fractionators, absorber-stripper columns, and reboiled absorbers. 

Description The process consists of a reactor section, continuous catalyst regeneration (CCR) section and product-recovery section. Stacked radial-flow reactors (1) facilitate catalyst transfer to and from the CCR catalyst regeneration section (2). A charge heater and interheaters (3) achieve optimum conversion and selectivity for the endothermic reaction. Reactor effluent is separated into liquid and vapor products (4). The liquid product is sent to a stripper column (5) to remove light saturates from the C6 aromatic product. Vapor from the separator is compressed and sent to a gas recovery unit (6). The compressed vapor is then separated into a 95% pure hydrogen coproduct, a fuel-gas stream containing light byproducts and a recycled stream of unconverted LPG. 

Because of the high yields, the Vinnolit DC reactor can be operated in the stand-alone mode. However, if the reactor is part of a complete VCM plant, offgas can be sent to the oxychlorination reactor to recover the remaining small quantities of ethylene. If sales-EDC specification is the target, only a small stripper column is required to eliminate traces of HCI. 

Description The TAC9 process consists of a fixed-bed reactor and product separation section. The feed is combined with hydrogen-rich recycle gas, preheated in a combined feed exchanger (1) and heated in a fired heater (2). The hot feed vapor goes to a reactor (3). The reactor effluent is cooled in a combined feed exchanger and sent to a product separator (4). Hydrogen-rich gas is taken off the top of the separator, mixed with makeup hydrogen gas, and recycled back to the reactor. Liquid from the bottom of the separator is sent to a stripper column (5). The stripper overhead gas is exported to the fuel gas system. The overhead liquid may be sent to a debutanizer column or a stabilizer. The stabilized product is sent to the product fractionation section of the UOP aromatics complex. 

Table 6.21 SUMMARY OF EQUATIONS FOR SIZING ISOTHERMAL ABSORBERS AND STRIPPERS - COLUMN HEIGHT...

TABLE 6.22 Calculation Procedure for Sizing Isothermal Absorbers or Strippers-Column Height ... 

Other analyzers include gas chromatography, which is a sensitive, automated, and semi-continuous technique in which CO is separated from water, CO2, and hydrocarbons (other than methane) by a stripper column and CO is passed through a catalytic reduction tube where it is converted to methane. The converted CO is passed through a flame ionization detector its sensitivity range is 0.026 to 43.7 ppm (IPCS, 1999). Other methods such as small personal exposure monitors (PEMs) can measure CO concentrations on a continuous basis and store data on internal digital memories (Ott et ah, 1986). 

Rigorous distillation models can be used to model absorber columns, stripper columns, refluxed absorbers, three-phase systems such as extractive distillation columns, many possible complex column conflgurations, and columns that include... 

---