Final treatment stage

At this stage, the fiber is eontaminated with acid and free sulfur and undergoes a series of operations to effeet final purifieation. Aeid is removed by washing with water and sulfur is removed by treatment with about 0.3% NaOH. Sometimes, at this stage, it is bleaehed with alkaline sodium hypoehlorite (0.1% available chlorine) to give a whiter fiber, followed by treatment with sour, whieh is about 0.2% sulfuric or hydrochloric acid and then, washed in water and finally dried. 

A finish (e.g., mineral oil), is applied and the fiber wound onto a bobbin, or if the finish is water based (e.g., sodium oleate/ oleic acid), it is applied prior to the drying stage. 

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UHT milk differs from pasteurized milk mainly in the heat treatment employed for sterilization. Usually UHT milk is heated at 130° to 150°C for 2 to 8 seconds and is then aseptically packaged. In the final heating stage, steam is injected directly into the milk, or the milk is infused into a steam chamber, followed by flash evaporation to remove added water (steam). An alternative procedure, the indirect method, involves heating milk across a stainless steel barrier, using high-pressure steam as the heating medium (Mehta 1980). 

Equation (4.15) should be considered the final oil-treatment stage, in which a 0.5 to 1% water cut in treated oil is produced. Here a heater-treater-type horizontal vessel is more commonly used. A direct-fired burner-heater is normally placed in a front section of the horizontal treater. Controlling the system temperature for viscosity is important and may be mandatory for successful water dehydration. 

The finished starch slurry from the final hydroclone stage may be further processed in alternative ways (a) dried directly and sold as unmodified com starch (b) modified by chemical or physical treatment in a way that preserves the granule structure, then rewashed to remove residual reactants, and dried (c) gelatinized and dried (d) chemically or physically modified and then dried (e) hydrolyzed either completely to D-glucose or partially hydrolyzed to give mixtures of soluble oligosaccharides and D-glucose (see Chapter 21), which can be fermented to yield ethanol and other products. 

The Army has just begun to evaluate permitting strategies for the PBNSF. As with MAPS, construction and initial operation of the facility could proceed under a RCRA RD D permit. After operations at the facility become routine, the PBNSF operations could be transitioned to the full RCRA permit. Permitting activities for PBNSF are still at an early stage, and with the final treatment technology yet to be decided, it remains unclear what problems may be encountered. 

Three sets of cookies were prepared, namely control cookies with no antioxidant added, sample cookies with clove extract as antioxidant and deliberately made-rancid cookies . In order to detect the rancidity profile of the cookies, the e-nose system was trained with the deliberately made-rancid cookies . These training sets of cookies were prepared by keeping control cookies in a rancidity chamber for 14, 21 and 28 days. The chamber was kept at 40 °C and UV light was used to promote oxidation. On completion of the ageing treatment, the samples were removed from the rancidity chamber and stored in the conservation chamber to maintain the final rancidity stage [99]. 

Aldehyde linearity is high (ca. 90%). Sufficient N-methyl-pyrrolidone (NMP ca. 40%w) and some water (1 -2%w) are applied to achieve a one-phase system in the reactors. After reaction, water is added in a mixer (phase ratio 1 1 v/v), followed by efficient phase separation in a settler, with virtually all catalyst in the NMP/water layer. The crude product layer is subjected to a multi-stage water extraction to remove residual NMP and catalyst, and a final treatment over a silica-bed to reduce Rh leach levels from 0.2 ppmw to 0.02 ppmw. The recycle catalyst layer (in NMP/water) is dried in two steps, to evaporate water and achieve the low water concentrations required for one-phase reaction, and then recycled to the reactors. Water is recycled, from evaporators, via water extraction, to the mixer. The flexibility of this process with respect to alkene carbon number seems excellent good performance has been found for Cs-C aUcenes [61]. 

While the reactors, which provide the chemical treatment stages, are at the heart of many processes, there are some in which the reactor is an inconsequential unit and others in which it is completely absent. The unit operations, which provide the physical treatment and separation in the preparatory and final stages, are, as seen in earlier chapters, just as important. This particular Case study is a small reminder of these facts. 

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