Conventional recovery

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 refineries or areas in which two or more alkylation units are operated, one SARP unit large enough to process the used alkylation acid from all of the alkylation units could be installed. The recovered acid in the form of isobutane-DIPS extract could be sent to the various alkylation units as needed or desired. Such a larger SARP unit would not only have a lower cost per unit of capacity, but would also have additional advantages if further processing of the SARP reject acid were carried out prior to conventional recovery. 

If the acid concentration is too low for conventional recovery by extraction, and if recovery of water is of interest as well, an elegant industrially proven solution of the problem is a multieffect azeotropic distillation. This process was developed by the BASF in Ludwigs-hafen/Germany [58]. 

Conventional recovery primary and/or secondary recovery often... 

When the aromatic chemicals are the desired products, hydrogenation is more severe to yield an olefin-free product suitable for extracting the aromatics by one of the conventional recovery processes. 

Conventional recovery from sandstones is often as low as 20 0% of the oil in place, and improved recovery technologies can increase this by 10-20% (i.e. to 30-60% of the oil in place). Only exceptionally is more than 60-65% of the oil in place recovered. Various physical processes that are linked to Darcy flow, i.e. capillarity, viscosity permeability, heterogeneity, and pressure gradients, dictate the amount of oil recovered. 

Preliminary economic evaluations of this scheme have indicated that it would be more economic than the conventional recovery process, particularly if a higher pulp yield were obtained. This process would also have a higher thermal efficiency than the conventional process. 

The conventional recovery route would involve using a CCD circuit to wash the leached solids and recover a leach solution. The leach solution would then be treated by (for example), pH adjustment and oxidation to precipitate Fe/Al from solution, mixed hydroxide precipitation of Ni/Co (along with Cu, Zn) and finally environmental treatment to precipitate Mn from solution. Mixed sulfide precipitation could also be used. The use of a CCD circuit involves capital and necessitates adding a lot of water to the circuit to wash the solids. 

The stability of the final mixture must be guaranteed to maintain high extraction yields. Since petroleum naturally exists in certain underground formations where it is adsorbed onto the rocks pores, conventional recovery methods are usually capable of removing only 30% of the oil. This can be credited, basically, to three aspects high viscosity of the oil, geology of the formation, and high interfacial tensions between the reservoir s fluids. 

The coupling of lla-hydroxyprogesterone 11-hemisuccinyl-bis-jS-aminoethyl-disulphide monoamide to agarose cyclic imidocarbonate produces a novel derivative, since coupling is effected via a disulphide bridge. The aflSnity material obtained was designed to see if it was possible to recover adsorbed proteins that are unstable under conventional recovery conditions, but that are stabilized by 2-thioethanol. 

The first step in the conventional recovery processes is heating the fermentation beer to 80—100 °C and increasing the pH to 10 to kill the bacteria, coagulate proteins, and maintain calcium lactate s solubility in the beer. The crude calcium lactate solution is then filtered, decolorized with activated carbon, and concentrated by evaporation. Lactic acid is recovered by addition of sulfuric acid and then further purified by one of the following routes (O Fig. 1.11) ... 

These purification processes are often combined with liquid-liquid extraction, ion exchange, and adsorption on solid adsorbants. However, for every ton of fermentation lactic acid produced by the conventional recovery process, about 1 t of gypsum (CaS04-2H20) by-product is also produced. Ecological and economical disposal thus becomes a problem for a large-scale production facility. 

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