Oil retention

To be of value in an oil decolorizing operation, a relatively small amount of clay must reduce color substantially. Oil retention must be low, ie, only a small amount of oil is retained in the clay during the decolorization process. Further, the clay must be readily removed by filtration. 

Oil Retention Boom A floating baffle used to contain and prevent the spread of floating oil on a water surface. 

Typical Oil Retention Capacities for Kerosene in Unsaturated Soils... 

Viability of Starch Derivatives as Flavoring Encapsulants. The capillary GC vapor phase flux term (defined by a percent external standard or ZEStD flux) previously described (34) was used to screen starch derivatives (oxidized, dextrinized and/or covalent amino acid linkage) as to their flavor encapsulation potential. The samples were prepared as previously described (34) with the exception of an added reduced pressure deaeration step, thus allowing the use of the headspace diffusivity versus retention standard curves to predict volatile lemon oil retention following spray drying. 

Table II. Lemon oil retentions (20%db) of spray-dried base starches...

Given the excellent lemon oil-incorporated emulsion stabilities of both polymers, the excellent dryer retention performance of the Control material and good lemon oil retentions using the Oxidized starch, scaled-up systems were prepared and dried. One... 

Substantial improvement (about 50%) of lemon oil encapsulation efficiency was attained for the covalently-linked phenylalanine-Oxidized starch wall material over the Oxidized starch control. In fact, this particular glycoamine resulted in lemon oil retentions following drying in the mini-spray dryer which surpassed both the Control and lipophilic starches (See Table IV). Dry blending phenylalanine with the Oxidized starch base exhibited the benefits associated with covalently linked glycoamine production via lemon oil vapor phase flux analysis. 

The other two glycoamine derivatives failed to substantially improve polymer performance. Aspartame linkage to the Oxidized starch resulted in improved lemon oil encapsulation efficiency over the Oxidized material, alone, but not to the extent of the phenylalanine glycoamine polymer. Covalent attachment of phenylalanine to the Control starch was actually a slight detriment to lemon oil retention versus the control starch (48.7% retention in the mini-dryer versus 50.4%, respectively), although this difference was not deemed significant. 

This study supports the hypothesis that high DE maltodextrins and syrup solids permit the formation of encapsulated products with excellent stability to oxidation. Different enzyme-hydrolyzed starches yielded encapsulated orange oils which varied in stability amylomaize and potato maltodextrins exhibited the poorest stabilities while normal corn, waxy corn, cassava, rice, and wheat glucose syrup solids yielded the best and approximately equivalent shelf-lives. Based on oil retention during drying, amylomaize, wheat, rice, and cassava yielded satisfactory products. 

A 10 gram sample was placed in a 200 ml round bottom flask and 100 ml of distilled water added. A Dean-Stark trap and condenser were used and the mixture was brought to a boil. The steam distilled oil was measured after four hours versus control mixtures. In order to measure surface oil on the spray-dried powders, the powder was first washed with a solvent (ethyl ether or hexane) then oil retentions were run by the steam distillation method illustrated above. Differences in oil volume for solvent washed versus non-washed were attributed to surface oil on the spray-dried powders. 

Emulsions of lemon oil stabilized with gum arabic, a conventional starch dextrin and a low viscosity starch octenylsuccinate were spray-dried and evaluated for encapsulating efficiencies. Oil retentions and surface oil determinations were made according to the Materials and Methods section. TABLE 3 demonstrates the superiority of the starch octenylsuccinate in flavor retention and surface oil to gum arabic and a starch dextrin (5) ... 

Starch octenylsuccinates offer excellent emulsifying properties, flavor oil retention and good oxidation resistance versus gum arabic. They can be made on a variety of starch bases, dextrins or fluidities which provide versatility and improved spray-drying costs. Starch octenylsuccinate are low in cost, domestically produced and are not subject to the market fluctuations that gum arabic encounters. 

In summary, we have found that the optimum (within the limits of this study) a for shelf-life is 0.54. In addition, the dryer inlet and exit air temperatures had no effect upon oil retention and perhaps only a minor effect upon shelf-life. If there is a significant effect it is that the higher inlet air temperature actually yielded a better shelf-life. A higher temperature differential means that dryer throughput also is increased and operating costs are cut. The more product that can be produced per hour, the lower the production costs. A larger temperature differential also results in a higher final product moisture. 

The surface oil content of the three encapsulated orange oils ranged from 102 (powder A) to 909 (powder C) mg/100 g powder, which corresponded to 0.67(powder A) and 7.10 (powder C) oil. Powders B and C had about 2 1/2 and 9 times surface oil as compared to powder A. This was not expected since powders with larger diameters had less calculated surface area as shown in Table I. It is therefore speculated that other powder characteristics, e.g. surface morphology, may play an important role on the oil retention properties and should be further studied. 

Retention time. A certain amount of oil storage is required in the vessel to assure that oil reaches equilibrium and flashed gas is liberated. Additional storage is required to assure that free water has time to coalesce into droplet sizes sufficient to fall in accordance with Eq. 1. It is common to use retention times from 3 to 30 min depending on laboratory or field data. If this information is not available, an oil retention time of 10 min is suggested for design. 

The clean water flows horizontally through the unn and falls into the clean-water outlet chamber overflowing the adjustable water-outlet weir plates. The height of this water weir as measured from tank inside bottom decides ihc working level of the coalescer unit A sheen baffle is located just before (lie water-outlet weir. The sheen baffle captures small oil droplets that might pass undet the oil-retention baffle. The buildup of oil film at the sheen baffle is so slow that no skimming device is required This oil buildup gets hack into the separation chamber when the unit is shut down for planned maintenance purposes... 

Katagiri [62] investigated the combination of silica-alumina fibers and wood MFC/nanocellulose (95/5 wt %). A further development is oil-retaining sheets with good durability for cleaning rolls [63], which are made from 100 parts inorganic fibers to 5 parts wood MFC/nanocellulose. These sheets are characterized by a weight of 36.3 g/m2, thickness of 0.21 mm, void volume of 92%, and silicone and oil retention capacity of 0.74 g/cm3. 

A flow chart of a long mix neutralization process is shown in Fig. 34.19. The recommended retention time for soybean oil in this system is 6 min and was shortened by a major improvement in caustic-oil retention mixers developed by the Alfa Laval Company, Tumba, Sweden, in the mid-1990s.103... 

The stracture of the multilayered emulsions may be preserved during spraydrying, enabling the delivery of emulsions with multilayered interfaces in a powder format. Spray-dried tuna oil powders made from emulsions containing oil droplets with lecithin-chitosan membranes, with added com symp showed good oil retention and water dispersibility (Klinkesom et al. 2006). 

The major focus for maximizing performance of activated carbon is to provide an optimum balance between increasing adsorptive capacity for polyaromatic hydrocarbons and dioxins while decreasing oil retention in the filter cake. It has been found that steam-activated carbon derived from peat yields the best combination of properties for this application. 

A second drawback (121) is that oil retention is increased as average particle size is decreased. However, the negative effect (oil loss) may be partially offset because less clay can be used. The loss of filtration rate is, in any event, a far more serious problem because this immediately impacts the primary measure of plant productivity—the rate at which fats and oils are produced. 

---