Field application recovery

The field nontarget arthropod data for pyrethroids summarized in Table 9 indicate that for all pyrethroids there was an initial reduction in abundance for some species shortly after application. There was a trend of more marked effects at the higher full field application rates with less marked affects at the lower drift rates tested (e.g., Deltamethrin, bifenthrin, and esfenvalerate). Also there was a trend of greater selectivity (i.e., fewer taxa affected) at lower drift rates (e.g., /amMa-cyhalothrin and Deltamethrin). For nearly all the pyrethroid field studies, either full or partial recovery of affected taxa was reported by the end of the field study or growing season, and in some cases for certain taxa, recovery occurred within 1-3 weeks. 

Pilot studies and field applications have shown vacuum-enhanced pumping to increase the rate of free-product recovery and in many cases significantly reduce the amount of groundwater recovered with the free product. 

Concentration and Recovery of Solutes. The RO method was evaluated by using small-scale concentrations and selected model organic solutes. Similar concentrations were performed by other researchers by using alternate sampling methods as part of a comparison study. The concentration provided a 50-fold volume reduction (500 L down to 10 L). Field applications of the RO method usually involve sample volumes of 2000-8000 L. No steps were taken to condition membranes and equipment prior to the laboratory tests. This laboratory performance evaluation was conducted, in many respects, as a worst case exercise. 

Removal of volatile components from the liquid phase to a gas phase has been the object of much study in RPB devices. One of the early successful applications was oxygen removal from water for use in secondary oil field recovery and boiler water feed (7). The oil field application demonstrated oxygen removal from 6-14 ppm to less than 50 ppb in both 50-T/h and 300-T/h RPBs using natural gas for stripping. The packing had 92% porosity and 500-m2/m3 volumetric surface area... 

A., A Production Well Foam Pilot in the North Sea Snorre Field - Application of Foam to Control Premature Gas Breakthrough in Proc., 9th European Symposium on Improved Oil Recovery, The Hague, The Netherlands, 1997 paper 001. 

Field Application. The micellar-polymer process for enhanced oil recovery has been used in many field trials. Petroleum sulfonates are the most commonly used surfactant 41, 42). Other surfactants have been used, such as ethoxylated alcohol sulfates 43) and nonionic surfactants mixed with petroleum sulfonates 44). 

Field Application. Field trials of classical alkaline flooding have been disappointing. Mayer et al. (60) indicated that only 2 of 12 projects had significant incremental oil recovery North Ward Estes and Whittier with 6-8 and 5-7% pore volume, respectively. Estimated recovery from the Wilmington field was 14% with a classical alkaline flooding method (61). However, post-project evaluation of that field indicated no improvement over water-flooding (62). 

On the other end of the scale of sophistication are agglomeration methods needed for low cost applications in the field of recovery of small amounts of valuable materials by leaching and waste processing for disposal. Many finely divided particulate wastes cannot be deposited in landfills or similar open storage facilities because of the danger of recontamination by wind and water. Because, in this case, agglomeration is only an additional cost, the cheapest possible method must be selected. 

This shear reversibihty is very beneficial in enhanced oil recovery field applications. It improves the well injectivity because of the shear thinning effect at the perforation and near the wellbore. Far away from the wellbore, flow velocity is reduced and viscosity is restored. For the hydrophobically associating polymers, both shear thickening and shear thinning were observed by Bock et al. (1988). It has also been reported that the viscosity after shearing was stopped was higher than that before shearing (McCormick et al., 1988). 

Pritchett, J., Frampton, H., Brinkman, J., Cheung, S., Morgan, J., Chang, K.T., Williams, D., Goodgame, J., 2003. Field application of a new in-depth waterflood conformance improvement tool. Paper SPE 84897 presented at the SPE International Oil Recovery Conference in Asian Pacific, Kuala Lumpur, 20-21 October. 

This chapter will focus on the stability of foams flowing in porous media when in the presence of crude oil. Many laboratory investigations of foam-flooding have been carried out in the absence of oil, but comparatively few have been carried out in the presence of oil. For a field application, where the residual oil saturation may vary from as low as 0 to as high as 40% depending on the recovery method applied, any effect of the oil on foam stability becomes a crucial matter. The discussion in Chapter 2 showed how important the volume fraction of oil present can be to bulk foam stability. A recent field-scale simulation study of the effect of oil sensitivity on steam-foam flood performance concluded that the magnitude of the residual oil saturation was a very significant factor for the success of a full-scale steam-foam process (14). 

Foam has been used in field applications involving both cyclic and steam-drive processes. Many of the steam-foam tests have been performed in Kern County, California, where most of the U.S. heavy oil is produced. In many situations, foam has successfully increased both volumetric sweep efficiency and oil recovery rates (34). Generally, the application of foam has been considered to be a technical success but economically suspect. 

Metal recovery from industrial waste has recently been shown [101] to be an active area of magnetic field applications, the base system ranging from mine-waste to cable scrap. Fe, Co, Nl, Cr, Mn, Mo, Tl, Va, W, Ta, U, rare-earth metals and precious metals are the most obvious candidates for recovery in magnetic fields, although other substances, e.g. Zn, Pb, Mg, Ca, have also been the subject of successful recovery studies [e.g. 71]. 

A review on field applications of steam foams is given in [261]. It is shown that experiments on injection of aqueous steam foam surfactant solutions, conducted earlier gave a relatively low increase in oil recovery, but remained profitable nevertheless. To achieve better results, the reservoir structure must be taken into consideration for the choice of an optimum foam injection regime. 

Svorstol, I., Blaker, X, Xham, M.J., and Hjellen, A. (1997) A production well foam pilot in the north sea snorre field - application of foam to control premature gas breakthrough. Proceeding of the 9th European Symposium on Improved Oil Recovery, The Hague,... 

Mungan, N. "Enhanced Oil Recovery Using Water as a Driving Fluid, Part 5 - Alkaline Flooding Field Applications , World Oil, Vol. 193, No. 1, July 1981, pp 181-190. 

We both found ourselves working on water-soluble polymers for oil recovery in the early 1980 s. Our previous backgrounds involved the synthesis and characterization of hydrocarbon polymers for everything from elastomers to plastics. As such, we were largely unprepared for the special difficulties associated with water soluble polymers in general, and their use in enhanced oil recovery (EOR), in particular. Oil patch applications have a jargon and technical heritage quite apart from that usually experienced by traditional polymer scientists. At that time, no books were available to help us "get up to speed" in the polymers for oil recovery field. Since then, there have been a number of symposia on this topic, but still few books, especially from the polymer (rather than the field-applications) perspective. 

Water-soluble polymers have been reviewed with particular emphasis on their application in improved oil recovery. These polymers have potential for use in mobility control, drilling fluids and profile modification. Partially hydrolyzed polyacrylamide and xanthan gum are the most commonly used water-soluble polymers in oil field applications. The apparent viscosity of these polymers depend on polymer type, molecular weight, charge density, concentration, shear rate, salt concentration, and pH, as follows ... 

Thus, when considering the required stability limits of a polymer for field application, the actual timescale of operation of the polymer oil recovery mechanism must also be examined. Obviously, this is also related to the physical size of the reservoir system and the planned injection/production rates. However, it should again be stressed that a careful analysis of the recovery mechanism may assist in the polymer design tolerances associated with chemical degradation. As a final practical comment on this matter, it is still recommended that, in field applications, the most stable available polymers should be used which can also achieve other design specifications. 

This chapter will break slightly with the tradition of other reviews of improved oil recovery methods in that a selection of field applications will not be explicitly discussed. Such applications have already been reviewed by a number of workers (Jewett and Schurz, 1970 Sloat, 1971, 1972 Agnew, 1972 Chang, 1978) whilst ongoing field reports have also been described (EOR Field Reports, SPE). In addition, there are about 100 papers and reports describing particular field polymer flood applications in the USA (e.g. Jones, 1966 Rowalt, 1973 Clampitt and Reid, 1975) and, more recently, in Europe (e.g. LaBastie and Vio, 1981 Maitin and Volz, 1981) and the Middle East (e.g. Koning and Mentzer, 1988). It is felt, therefore, that the inclusion of specific field cases in this chapter would serve only to date the... 

Zettiitzer, M. and Volz, H. 1992. Comparison of Polyacrylamide Retention in Field Application and Laboratory Testing. Paper SPE 24121 presented at the SPE/DOE Enhanced Oil Recovery Symposium, Tulsa, 22-24 April. DOI 10.2118/24121-MS. 

Ken Green is a Senior Technologist for the Alberta Research Council. Ken is currently utilizing simulation programs to improve the design of polymer field applications. His work incorporates laboratory results to calibrate reservoir simulators for field-scale simulations. He has over 30 years of experience in laboratory studies for erihanced oU recovery. 

Analytical models using classical reservoir engineering techniques such as material balance, aquifer modelling and displacement calculations can be used in combination with field and laboratory data to estimate recovery factors for specific situations. These methods are most applicable when there is limited data, time and resources, and would be sufficient for most exploration and early appraisal decisions. However, when the development planning stage is reached, it is becoming common practice to build a reservoir simulation model, which allows more sensitivities to be considered in a shorter time frame. The typical sorts of questions addressed by reservoir simulations are listed in Section 8.5. 

A considerable percentage (40% - 85%) of hydrocarbons are typically not recovered through primary drive mechanisms, or by common supplementary recovery methods such as water flood and gas injection. This is particularly true of oil fields. Part of the oil that remains after primary development is recoverable through enhanced oil recovery (EOR) methods and can potentially slow down the decline period. Unfortunately the cost per barrel of most EOR methods is considerably higher than the cost of conventional recovery techniques, so the application of EOR is generally much more sensitive to oil price. 

In the decoupled scheme the solution of the constitutive equation is obtained in a separate step from the flow equations. Therefore an iterative cycle is developed in which in each iterative loop the stress fields are computed after the velocity field. The viscous stress R (Equation (3.23)) is calculated by the variational recovery procedure described in Section 1.4. The elastic stress S is then computed using the working equation obtained by application of the Galerkin method to Equation (3.29). The elemental stiffness equation representing the described working equation is shown as Equation (3.32). 

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