Recovery factors affecting

Factors affecting RO membrane separations and water flux include feed variables such as solute concentration, temperature, pH, and pretreatment requirements membrane variables such as polymer type, module geometry, and module arrangement and process variables such as feed flow rate, operating time and pressure, and water recovery. 

Two principal factors affected the U.S. sulfuric acid industry in the 1980s. The first was the increased availabiUty of recovered sulfur vs Frasch sulfur (see SuLFURREMOVAL AND recovery). This occurred because of environmental concerns and regulations forcing more sulfur to be recovered at refineries, power plants, etc. The effect of this change was that the cost of sulfur in the marketplace became driven largely by the cost of nonsulfur industries, rather than by the traditional discretionary sulfur producers, and tended to stabilize U.S. sulfur prices. 

The origins and composition of plastics wastes and factors affecting their recycling are discussed. Partieular attention is paid to chemical recycling and incineration, with and without energy recovery, and a number of developments in chemical recycling techniques are examined. 19 refs. 

Several factors affect the overall economics of PHA production. These include PHA productivity, PHA content, yield of PHA on carbon source, carbon substrate cost, and recovery method employed. Figure 1 shows the production costs of P(3HB) by various P(3HB) contents and P(3HB) productivities [29]. The effect of P(3HB) productivity on the production cost is only related to the cost of the fermentation equipment [18]. However, the P(3HB) content has multiple effects on the volume of the fermentation equipment and the recovery process [17,18]. The increase of P(3HB) yield on carbon source and the use of less expensive carbon substrates reduce the cost of carbon substrate [17, 29]. Development of an efficient recovery method, which will be different for each bacterium employed, is also important to overall economics of PHA production. When the actual fermentation processes employing many different re-... 

Extraction of PHA from plants is likely to be a major factor affecting the production cost of PHA from crops and, therefore, the economic viability of this approach. In contrast to production of PHA from bacterial fermentation, where the production system is designed to produce only PHA, an agricultural production of PHA is likely to be most viable only through the recovery of not only PHA but also all other useful components of the harvested crop, i.e., oil, proteins, and carbohydrates. This fact, combined with the lower level of PHA accumulation in plants in comparison to micro-organism, is likely to make PHA recovery from plants a challenging task. 

Strain hardening effect, 20 224 Straining efficiency, 77 340 Strain rate, 73 473 Strain recovery rate (Rr), in testing shape-memory polymers, 22 361 Strain sensors, 77 150, 151-152 Strain tensor, for noncentrosymmetry pont group crystals, 77 93-94 Strain versus time curve factors affecting, 73 473 material and microstructure effect on, 73 473-474... 

The recovery factor is defined as the ratio of additional steam provided by injection to the amount of water injected over the same period of time. Additional steam is the steam produced at the new decline rate (or improvement rate) due to injection minus the steam production calculated at a decline rate without re-injection. The recovery factor defined on the basis of production data may be different from that defined on the basis of geochemical data if considered on a well-by-well basis. However, the combined recovery from all production wells affected by one or more injection wells should agree when applying both methods given sufficient time, since (1) the total amount of boil water should appear as steam in production wells and be reflected in the production data, and (2) the steam originally to be produced from a given well but replaced by injection-derived steam should eventually be produced in other wells. 

Recovery factor calculations may not be possible under certain situations, including (1) a decrease in steam flow rate due to water breakthrough (2) scale deposits in the well-bore and/or fracture conduits (3) a fluctuating flow rate and (4) the completion of additional production wells in injection-affected areas, which will have an impact on the decline rates of nearby production wells. 

Room temperature ionic liquids have potential as extractants in recovery of butyl alcohol from fermentation broth water solubility in ionic liquid and ionic liquid solubility in water are important factors affecting selectivity of butyl alcohol extraction from aqueous solutions (Fadeev and Meagher, 2001). 

Meyer et al. [173] showed that supercritical fluid extraction results can give recoveries comparable to Soxhlet extraction methods, even for soils with high carbon contents. McNally et al. [174] have studied factors affecting the supercritical fluid extraction of soils. It was shown that soil type affects the recovery of moderately polar analytes. In general the organic carbon content of the soil governs analytical recovery. 

The main factors affecting monosaccharide recovery in dilute-acid hydrolysis are catalyst concentration, reaction time, and temperature, whereas enzymatic hydrolysis is also dependent on additional factors such as substrate structure, and type and ratio of enzymatic activities present in the commercial enzyme preparations. The most important enzymes for xylan hydrolysis are endo-l,4-(3-xylanases (which attack the main chain) (3-xylosidases (which hydrolyze xylooligosaccharides to xylose) and accessory enzymes, such as acetyl xylanesterases, a-glucu-... 

As with the volatility range, recovery generally is most effectively increased by raising the sample temperature. Additional factors affecting sensitivity include trapping and desorption efficiencies, column resolution, interferences, and detector sensitivity. For oils the lower limit of detection for the majority of the compounds listed in Tables I and II is on the order of 1 to 100 ppb. For oil samples, nonane, which is often added as an internal standard, is detectable to less than 5ppb. 

Totaro et al. published a detailed paper on the factors affecting measurement of cerebrovascular reactivity when measured by NIR [49]. Some of the points covered were the relative transparency of the skin, skull, and brain in the 700- to 1100-nm region and the oxygen-dependent tissue absorption changes of hemoglobin. Their study covered all relevant factors, such as age, sex, reproducibility (often neglected in many academic papers), and venous return. The test was based on a 3-min baseline, a 3-min hypercapnia (5% C02 in air), and a 2-min recovery period. 

The ready availability of starch-based industrial wastes and their renewable nature merit their use as substrates for poly-betahydroxybutyrate (PHB) production from activated sludge. This would not only utilize the excess sludge generated and reduce the load on landfills, but would also contribute to reduction in the cost of PHB production by avoiding sterile conditions and pure carbon sources for maintenance and growth of pure cultures. PHB content is the most important factor affecting the production cost of PHB due to its effect on PHB yield and recovery efficiency, followed by cultural conditions and carbon substrates used (Khardenavis, 2007). 

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