Mechanical extraction

Estimations based on statistics can be made for total accuracy, precision, and reproducibility of results related to the sampling procedure being applied. Statistical error is expressed in terms of variance. Total samphng error is the sum of error variance from each step of the process. However, discussions herein will take into consideration only step (I)—mechanical extraction of samples. Mechanical-extracdion accuracy is dependent on design reflecding mechanical and statistical factors in carrying out efficient and practical collection of representative samples S from a bulk quantity B,... 

A factory building (Fig. 11.43) consists of two spaces a hall with mechanical extract ventilation for combined abrasive and chemical treatment and subsequent bonding and a naturally ventilated assembly hall. 

VOCs are released during chemical cleaning of bonding surfaces. The extract system is designed on the basis of the steady-state concentration determined for maximum source strength and considering the mechanical extract ventilation only and no air-exchange with the assembly hail. Ehis concentration must be kept below the threshold concentration (TVL) which is set to 300 mg/kg in this example. 

FIOURE M.43 The fectory buMdmg with the two haJmechanical extract system. 

Air, recirculated Any air that is mechanically extracted from a space that, after suitable treatment, is returned to the space. 

Air relief The release of air from a space, either by pressure difference or mechanical extraction. 

Replacement The process of air entering a space to fill the void created by either natural or mechanical extraction. 

Table exhaust Mechanical extractions of pollutants generated on a worktable during a process. The extraction takes... 

Mayer TE, Hamann GF, Brueckmann H. Mechanical extraction of a basilar-artery embolus with the use of flow reversal and a microbasket. N Engl J Med 2002 347 769-770. 

Uquiche E, Jerez M and Ortiz J. 2008. Effect of pretreatment with microwaves on mechanical extraction yield and quality of vegetable oil from Chilean hazelnuts (Gevuina avellana Mol). Innov Food Sci Emerg Technol 9(4) 495-500. 

The Mini-Miser dewatering system uses hydraulic pressure to mechanically extract liquids from sludges, sediment, and solids. The system incorporates a patented press design that has previously... 

Juice Cloud. Mechanical extraction of citrus fruits yields a turbid suspension of wall fragments and cellular organelles in a serum composed primarily of cell vacuolar fluids. In most citrus juice products, such a suspension of fragments and organelles is a desirable component, since it provides most of the characteristic color and flavor (28). Essence and peel oils suspended in juice contribute desirable citrus notes to flavor, and these oils are rapidly adsorbed by juice particulate material shortly after extraction (29). 

A defatted product is also marketed. Defatted wheat germ meal is obtained after the removal of part of the oil or fat from wheat germ meal and must contain not less than 300g/kg CP IFN 5-05-217 Wheat germ meal mechanical extracted. 

Raw groundnuts contain 400-550 g/kg oil. Groundnut meal is the ground product of shelled groundnuts, composed principally of the kernels, with such portion of the hull, or fibre and oil remaining after oil extraction by a mechanical extraction process. Mechanically extracted meal may contain 50-70g/kg oil, and thus tends to become rancid during storage, especially... 

Table 4.1.5A. Canola meal expeller (IFN 5-06-870).The residual product obtained after extraction of most of the oil from canola seeds by a mechanical extraction process (not defined by AAFCO or CFIA).

Table 4.1.10A. Flaxseed (linseed) expeller (IFN 5-02-045). The product obtained by grinding the cake or chips which remain after removal of most of the oil from flaxseed by a mechanical extraction process. It must contain no more than 100 g fibre/kg. (From AAFCO, 2005.)...

Cs[(C2BqH11)2Co] are dissolved in 20 ml of acetic anhydride, 3.4 g (25 mmol) of powdered tellurium followed by 2 ml of concentrated sulfuric acid are added, and the mixture is heated at 100° for 4h, then filtered. Most of the acetic anhydride is removed from the filtrate at 80° (bath temperature)/10 torr. The residue is shaken with a mixture of 50 ml of water plus 50 ml of benzene, the aqueous layer is separated and discarded. The benzene is distilled under vacuum from the remaining non-aqueous phase, the residue is dissolved in 50 ml of acetone, and this solution is poured into 60 ml of methanol containing 6.0 g of potassium hydroxide. 2 ml of dimethyl sulfate are added, the mixture is shaken for 10 min, and excess dimethyl sulfate is removed by shaking the mixture with 10 ml of 15% aqueous ammonia. 50 ml of benzene and 200 ml of water arc added, the orange-colored benzene layer is separated, washed with two 50 ml portions of water, and filtered. The filtrate is concentrated to a volume of 10 ml, and poured onto a column containing 100 g of silica gel which is then eluted with benzene/hexane (1/1, v/v). The red band with Rt = 0.2 is separated mechanically, extracted with benzene, and the extract is concentrated to a volume of 10 ml. The viscous residue is covered with a layer of hexane and red needles separate overnight yield 0.15 g (3%). 

Van der Linden, Wassink and Theusink, have recently reported on a novel technique for mechanically extracting water though the use of a pressure differential across fabrics which is on the order of 0.5 atmospheres (6). The pressure differential is developed by either throttling high pressure steam (6 atm.) or compressed air through a one-mil wide nozzle (Machnozzle). Steam is usually employed since the nozzle operates isoenthaipically,... 

Copra is the dried kernel of coconuts. Fresh kernels contain approximately 50% moisture. Various drying methods are employed to bring down the moisture content ideally to 6-8% (see Table 3). At this level, mold growth in copra is inhibited. The conversion of kernel to copra is an essential step if the oil is to be drawn by the conventional mechanical extraction method. 

The dry process involves mechanical extraction of oil in cmshers or expellers with copra as feedstock (see Figure 3). Mechanical extraction may be supplemented with a second extraction, using solvents, to recover residual oil from the meal. 

Mechanical Extraction. Copra with 10-12% moisture content is conveyed to an automatic scale, passes through a magnetic chamber for the removal of tramp iron, and is ground to a particle size of approximately 0.3 cm in diameter. The particles are flaked to facihtate exposure of a large surface area. 

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