Wagging

Keywords production decline, economic decline, infill drilling, bypassed oil, attic/cellar oil, production potential, coiled tubing, formation damage, cross-flow, side-track, enhanced oil recovery (EOR), steam injection, in-situ combustion, water alternating gas (WAG), debottlenecking, produced water treatment, well intervention, intermittent production, satellite development, host facility, extended reach development, extended reach drilling. 

The most common solvent employed is carbon dioxide gas, which can be injected between water spacers, a process known as WaterAlternating Gas (WAG). In most commercial schemes the gas is recovered and reinjected, sometimes with produced reservoir gas, after heavy hydrocarbons have been removed. Other solvents include nitrogen and methane. 

To the extent that the segmental friction factor f is independent of M, then Eq. (2.56) predicts a first-power dependence of viscosity on the molecular weight of the polymer in agreement with experiment. A more detailed analysis of f shows that segmental motion is easier in the neighborhood of a chain end because the wagging chain end tends to open up the structure of the melt and... 

An extra amount of free volume is associated with chain ends, which are capable of wagging in a way that is not possible in the middle of a chain. Accordingly, as molecular weight decreases, Vj- increases, which, in turn, decreases Tg. The following expression has been found to describe this molecular weight dependence ... 

In addition to the descriptions of group vibrations as stretch and bend (or deformation) the terms rock, twist, scissors, wag, torsion, ring breathing and inversion (or umbrella) are used frequently these motions are illustrated in Figure 6.13. 

Figure 6.13 Illustration of (a) rocking, (b) twisting, (c) scissoring and (d) wagging vibrations in a CH2 group. Also shown are (e) the torsional vibration in ethylene, (f) the ring-breathing vibration in benzene and (g) the inversion, or umbrella, vibration in ammonia...

In 1990 world consumption of lanthanides was approximately 35,000 metric tons (45). The most important markets were the United States /Canada (32.8%), China (18.6%), Europe (15.8%), Japan (14.5%), Eastern Europe (9.5%), the rest of Asia (7.3%), and the rest of the world (1.4%). The principal rare-earth manufacturers in 1993 were Molycorp Inc. and RhcJ)ne-Poulenc in the United States RhcJ)ne-Poulenc and Treibacher Chemische WAG in Europe Shinetsu Chemical, Nippon Yttrium, Mitsubishi Chemical Inc., and Santoku Metal Inc. in Japan Indian Rare Earths in India and several additional companies located in the CIS and in the Baotou, Gansu, Yue Long, and Jiangxi provinces in China. 

Fig. 1. Carbon dioxide flooding. The WAG process, in which a CO2 slug is followed by alternate water and CO2 injections, is usually employed. The...

The WAG process has been used extensively in the field, particularly in supercritical CO2 injection, with considerable success (22,157,158). However, a method to further reduce the viscosity of injected gas or supercritical fluid is desired. One means of increasing the viscosity of CO2 is through the use of supercritical C02-soluble polymers and other additives (159). The use of surfactants to form low mobihty foams or supercritical CO2 dispersions within the formation has received more attention (160—162). Foam has also been used to reduce mobihty of hydrocarbon gases and nitrogen. The behavior of foam in porous media has been the subject of extensive study (4). X-ray computerized tomographic analysis of core floods indicate that addition of 500 ppm of an alcohol ethoxyglycerylsulfonate increased volumetric sweep efficiency substantially over that obtained in a WAG process (156). 

Structure Symmetry Ring breathing C-H stretch CH2 scissoring CHi wagging Ref. 

The conventional system in general use takes the compound from the blending mill, through an antistick applicator onto a festoon system with air cooling, and finally through a wig-wag take-off system into storage baskets. 

Why does an organic molecule absorb some wavelengths of IR radiation but not others All molecules have a certain amount of energy and are in constant motion. Their bonds stretch and contract, atoms wag back and forth, and other molecular vibrations occur. Following are some of the kinds of allowed vibrations ... 

Vancea L, Bennett MJ, Jones CE, Smith RA, Graham WAG (1977) Inorg Chem 16 897 further references therein... 

The C3 atom in the wagging mode n = 2 shifts more than the atom C2 in the wagging mode n = 3. 

Methanal (formol) presents an additional degree of freedom the out-of-plane wagging of the oxygen atom. In its singlet ground, X Ai, this molecule is planar. But, in its triplet and singlet lowest exited W A" and tt ), this molecule is pyramidal... 

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