Vacuum inbreathing


Epichlorohydrin Elastomers without AGE. Vulcanizates of ECH homopolymer and ECH—EO copolymer have outstanding ozone and gas permeabihty resistance. They also retain their flexibiHty at low temperatures and are fuel resistant. This combination of properties makes them important in automotive appHcations such as fuel, air, and vacuum hoses, vibration mounts, and adhesives. Homopolymer is used in adhesives because of its natural tack. Used as an additive, ECH—EO copolymer can also impart antistatic properties to plastics. Other industrial appHcations of these polymers include drive and conveyor belts hoses, tubing, and diaphragms pump parts including inner coatings, seals, and gaskets printing roUs and blankets fabric coatings for protective clothing pond liners, and membranes in roofing material. In oil weU drilling equipment, uses include drill-pipe protectors, packers, pipe sembbers, and submersible power-cable jacketing.  [c.557]

Vacuum Treatment. Milk can be exposed to a vacuum to remove low boiling substances, eg, onions, garlic, and some silage, which may impart off-flavors to the milk, particularly the fat portion. A three-stage vacuum unit, known as a vacreator, produces pressures of 17, 51—68, and 88—95 kPa (127, 381—508, and 660—711 mm Hg). A continuous vacuum unit in the HTST system may consist of one or two chambers and be heated by Hve steam, with an equivalent release of water by evaporation, or flash steam to carry off the volatiles. If Hve steam is used, it must be cuUnary steam which is produced by heating potable water with an indirect heat exchanger. Dry saturated steam is desired for food processing operations.  [c.359]

Commercial manufacture of peanut butter varies considerably. The influence of roasting time on sensory attributes and on chemical measurements of flavor components can be found ia Refereace 39 (see Flavor characterization). Shelled peanuts are heated to an internal temperature close to 145°C (81) to obtain the proper roasted flavor. At this temperature, free amino acids and sugar ia the peanut react to form pyraziaes, the main roasted-flavor components (130). The peanut is then quickly cooled to stop the cooking at a definite poiat to produce a uniform product. Next, blanching is used to remove the peanut skins and hearts. Peanut hearts (embryonic axes) should be removed from the kernels prior to peanut butter manufacture because they impart a gray color and bitter flavor to the product (109) likewise, defective nuts should also be removed. FiaaHy, a coarse or medium grind is made and the iagredients added and blended, ia which both salt (about 2%) and sugar (0—6%) impart flavor. Oil separation ia peanut butter products can be prevented by adding partially hydrogenated vegetable oils at levels of 3—5% it may also be controlled by keeping the product at about 10°C (109). The final gtind, at a temperature sufficient to obtain a melt of the stabilizer, produces the desired texture smooth, creamy, or chunky old-fashioned peanut butter, however, does not contain a stabilizer. Air is removed by vacuum, and the mixture is cooled to about 32°C before packagiag to ensure longer shelf life and proper crystallization of the fat. The vacuum or gas-flushed final package should remain undisturbed for about 12—24 hours to allow complete crystallization which prevents cracking, shrinking, or pulling away from the container.  [c.277]

Rubber-Modified Polystyrene. Rubber is incorporated into PS primarily to impart toughness. The resulting materials, commonly called high impact polystyrene (HIPS), are available in many different varieties. In mbber-modifted PS, the mbber is dispersed in the PS matrix in the form of discrete particles. The mechanism of mbber particle formation and mbber reinforcement, as well as several reviews of HIPS and other heterogeneous polymers, have been pubHshed (21,22,66—70). The photomicrographs in Figure 5 show the different morphologies possible in HIPS materials prepared using various types of mbbers (71,72). If the particles are much larger than 5—10 micrometers, poor surface appearance of moldings, extmsions, and vacuum-formed parts are usually noted. Although most commercial HIPSs contain ca 3—10 wt % polybutadiene or styrene—butadiene copolymer mbber, the presence of PS occlusions within the mbber particles gives rise to a 10—40% volume fraction of the reinforcing mbber phase (22,73). Accordingly, a significant portion of the PS matrix is filled with mbber particles. Techniques have been pubhshed for evaluating the morphology of HIPS (72,74,75).  [c.507]

Steam-setting operations can impart all forms of set to wool yam and fabric. Yams are normally steam-set in an autoclave at temperatures up to 90°C. A vacuum pump is used to remove air from the packages and allow even penetration of the steam into the yam packages and even setting. Fabrics are normally steam-set by winding them, interleaved with a cotton wrapper cloth, onto a perforated dmm through which steam is forced. This process is called decati2ing. The fabric roU can be placed in a pressure vessel so that the setting temperature can be raised above 100°C.  [c.351]

An example of the use of evaporating equipment in the food processing industry is illustrated in FigurelS. This is an example of continuous vacuum drying to produce milk crumb. Preconcentrated liquid material is continuously crystallized and dried through a viscous, pasty intermediate phase until a crumbly product is discharged via a piston lock system. Maillard-type reactions impart special flavoring to the final product. Exact temperature control produces a high-quality, good tasting product. The compact design for this system features a clean-in-place system that requires little floor space. The process provides safe processing during sticky, crustforming, intermediate stages of product processing.  [c.111]


See pages that mention the term Vacuum inbreathing : [c.296]    [c.229]   
Applied Process Design for Chemical and Petrochemical Plants, Volume 1 (1999) -- [ c.468 , c.469 , c.475 ]