Entrainer water removal

The fatty acids that emerge from the top of the column contain entrained water, partially hydroly2ed fat, and the Zn—soap catalyst. This product stream is passed into a vacuum dryer stage where the water is removed through vapori2ation and the fatty acid cooled as a result of this vapori2ation process. The dried product stream is then passed to a distillation system. 

A series of tests using Amberlite IR-12 (sulfonated polystyrene resin) to esterify diethylene glycol (DEG) using toluene as the entrainer for removal of water gave the results in Table 1 (53). 

A typical amine system is shown in Figure 7-4. The sour gas enters the system through an inlet separator to remove any entrained water or hydrocarbon liquids. Then the gas enters the bottom of the amine absorber and flows counter-current to the amine solution. The absorber can be either a trayed or packed tower. Conventional packing is usually used for 20-in. or smaller diameter towers, and trays or structured packing for larger towers. An optional outlet separator may be included to recover entrained amines from the sweet gas. 

Commonly, amine absorbers include an integral gas. scrubber section in the bottom of the tower. This scrubber would be the same diameter as required for the tower. The gas entering the tower would have to pass through a mist eliminator and then a chimney tray. The purpose of this scrubber is to remove entrained water and hydrocarbon liquids from the gas to protect the amine solution from contamination. 

The HPS liquid consists mostly of C3 s and heavier hydrocarbons however, it also contains small fractions of Cj s, H2S, and entrained water. The stripper removes these light ends. The liquid enters the stripper on the top tray. The heat for stripping is provided by an external reboiler, using steam or debutanizer bottoms as the heat medium. The vapor from the reboiler rises through the tower and strips the lighter fractions from the descending liquid. The rich overhead vapor flows to the HPS via the condenser and is fed to the primary absorber. The stripped naphtha leaves the tower bottoms and goes to the debutanizer. Usually, at least one draw is installed in the tower to remove the entrained water. 

Steam for sterilization can either be generated within the sterilizer, as with portable bench or instrument and utensil sterilizers, in which case it is constantly in contact with water and is known as wef steam, or can be supplied underpressure (350-400kPa) from a separate boiler as dry saturated steam with no entrained water droplets. The killing potential of wef steam is the same as that of dry saturated steam at the same temperature, but it is more likely to soak a porous load creating physical difficulties for further steam penetration. Thus, major industrial and hospital sterilizers are usually supplied with dry saturated steam and attention is paid to the removal of entrained water droplets within the supply line to prevent introduction of a water fog into the sterilizer. 

To ensure overall extraction of a polar solute, the pressure or density must be increased or a modifier must be added to the extraction fluid after an initial low-pressure extraction. In this way, the analyte of interest can be collected separately from the oily interference. Polar solutes may be removed more easily from matrices with higher moisture content. It is believed that the analyte is solubilized in the entrained water and removed from the matrix with physical removal of water. Since polar analytes benefit from the presence of water in samples, water has been added as a mobile phase modifier to enhance extraction recoveries (152). 

Hence, the entrainer enhances the water removal, ensuring simultaneously a recycle of alcohol to the reaction zone. As a consequence, the reaction rate can increase substantially. The comparison with a process without entrainer operating as pseudoabsorber shows that the catalyst loading can be reduced up to 50%. 

Ordinary rectification for the dehydration of acetic acid requires many trays if the losses of acid overhead are to be restricted, so that azeotropic processes are used exclusively. Among the entrainers that have been found effective are ethylene dichloride, n-propyl acetate, and n-butyl acetate. Water contents of these azeotropes are 8, 14, and 28.7 wt %, respectively. Accordingly, the n-butyl acetate is the most thermally efficient of these agents. The n-propyl acetate has been used in large installations, in the first stage as solvent for extraction of acetic acid and then as azeotropic entrainer to remove the accompanying... 

The entrainer-based reactive distillation column consists of a reactive section with a distillation section placed on top, in where the entrainer is responsible for removing the water out of the reactive section. The top vapour, which consists of entrainer, water and isopropanol, is condensed and two phases are obtained through decantation an aqueous... 

The main hydrogen stream from the cell is also hot and wet. Since hydrogen has a low solubility in water, it is usually cooled and cleaned of chlorine, salt, etc., by a direct, countercurrent contact with a cool spray of dilute sodium hydroxide in water. Clean hydrogen exits from the top of the cooler through baffles or plastic mesh placed so as to remove entrained water droplets. 

After calcination, the stuccos were cooled to room temperature with constant stirring to remove all entrained water vapor. The residual gypsum content and soluble anhydrite content as determined by phase analysis 9] were always less than 4.0 and 2.0%, respectively. 

Lhomme and Ourisson,11 in working on the oxidation of camphanols with lead tetraacetate in benzene found that there was considerable risk that very volatile products would be entrained during removal of the benzene by distillation. Since sulfolane has been used in the industry for the extraction of aromatics from hydrocarbon mixtures, they tried adding pentane and then extracting the solution several times with the nonmiscible sulfolane. The residual pentane solution could then be washed with water for the removal of sulfolane and recovery of the volatile cyclic ethers formed in the oxidation. The procedure was verified by showing that more than 70% of camphene could be recovered in this way. 

This approach is usually not practical for drops less than 100 pm, since for most situations large cross-sectional areas are needed to reduce the bulk velocity below the terminal settling velocities of such drops. An air stream with a 10 ft/s vertical velocity will entrain water drops less than about 700 pm, while a bulk velocity of 1.0 ft/s will entrain drops of about 100 pm or less. Gravity techniques can be used to remove large quantities of die latger-size dispersed-phase materia prior to some other segregation technique. 

The additional methane formed by methanation is insignificant compared to the residual unreacted methane (or methane slip) in the product gas. Product gas is cooled following methanation and entrained water is removed in a dehydrator. The product gas, which is primarily hydrogen and methane, is then delivered to the plant battery limits for use in downstream applications. 

---