Stand-retting

Standard state, for molecules, 24 687—688 Standard state enthalpy change for methanol synthesis, 25 305 Standard-state heat, 24 688 Standard-state heat of reaction, 24 688 Standards-writing organizations, 15 760 Standard Test Conditions (STC), 23 38 Standard test methods, 15 747—748 Standpipe pressure profiles, 11 818 Standpipes, in circulating fluidized beds, 11 817-819 Stand-retting, 11 606 Stannane, 13 613, 24 813... 

The feed was introduced by flowing dry helium as a carrier gas through a saturator containing freshly purified ethylbenzene kept at 25°C, to obtain an EB partial pressure of 10 Torr. Products were analysed by on-line G.C., using a column MBMA (Perkin Elmer), 30 m. The rate, r (mol- min l g"l) was calculated from r = Cq (F/W)-X, where c (mol- mP ), F (ml- min i), W ( g) and X (%) stand for the concentration of the feed, EB, at the inlet, flow rate, catal)ret mass and conversion, respectively. The contact time, F/W, was corrected for the flow at actual reaction temperature and reactor pressure. 

The fibers of flax, hemp, ramie, and other similar fibers are separated by a process called retting. The fibers are placed in vats and allowed to stand. Spontaneous fermentation springs up in the water living on the soluble matter from the fibers. There are a large number of different bacteria present both aerobic and anaerobic which produce enzymes which dissolve the pectin compound encasing the fibers. 

Cleanliness and freedom from nonfibrous matter is an important feature, and, in this respect, the physical imperfections that may result from improper retting can have a profound effect on the allotted grade. Adhering bark in any form results in downgrading, irrespective of the intrinsic value of the fiber, and, in the case of plants grown on flooded land, which stand in water, the bark becomes so difficult to remove that, for export, the root ends are cut off and sold separately as cuttings to be used in heavy yarns of low quality. 

In a parametric study on seawater RO. Soo-Hoo et al/ estimated the capital cost for a stand-alone seawater RO plant to produce 400 kL/day of potable water liom seawaterto be 1,100,000 (1981). Energy ret]uire-ments were tetween 9 W-h/L for a high-piessuie plant with no energy recoveiy, and S W-h/L for a lower pressure plant with energy recovery. Membrane replacement costs were approximately 40,(X)0/year. 

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