Rates recovery

Table 2. Residential Recovery Rate by Package Type ...

Mill Tailings. Recovery efficiency in ore processing is not 100%. Accumulated mill tailings contain tens of thousands of metric tons of uranium. Whereas improved techniques have been employed to recover some of this uranium, the recovery rate is still generally low, approximately 35—50%, owing to metallurgical problems and economic considerations (33). 

The total production of the U.S. paper industry in 1994 was ca 85 million metric tons with a compound aimual growth rate over the previous decade of 2.7%. The domestic production of paper and board plus imports and minus exports maintains a remarkably constant ratio with real gross domestic product in the United States. One sector of the paper industry that has grown at a higher rate than GDP is recycled papers and boards which is projected to grow at 6.8% aimuaHy. Over one-half of paperboard production in the United States is from recycled fiber, and the industry as a whole is expected to achieve 50% recovery rate for paper and board products by the end of the twentieth century (see Recycling, paper). 

Poly(vinyl alcohol) can be recovered from the desizing Hquid by means of commercial ultrafiltration equipment. Recovery rates and effluent losses ate inversely proportional to the PVA solution viscosity and independent of the degree of hydrolysis. 

Ethane is used by petrochemical plants to make ethylene, a primary building block for many plastic products. Butane and condensate are used by refineries producing automotive fuel. For production of NGL s (natural gas liquids), die plant s recovery rate of 98% of ediane and 100% of all odier liquid products contained in natural gas, is among die best in die world. 

The turboexpander lowers the temperature of the product to -100°F, causing it to liquify. Now at 350 psig pressure, the liquid from this process enters the demethanizer tower where it mingles with the previously introduced stream of liquid. The turboexpanders provide a 92% recovery rate while the former system, a backup Joule-Thomson valve, was able to provide only a 60% recovery rate. The volume of gas entering the turboexpanders can vary up to 10% yet, the different flowrates do not significantly affect the efficiency of these units, which are rated at 2,400 hp at 16,000 rpm. 

Sample stability becomes increasingly important as the time between sampling and analysis increases. Effects of temperature, trace contaminants, and chemical reactions can cause the collected species to be lost from the collection medium or to undergo a transformation that will prevent its recovery. Nearly 100% recovery is also required because a variable recovery rate will prevent quantification of the analysis. Interference should be minimal and, if present, well understood. 

A cascade system should improve the recovery rate by trapping solvent in the second stage that escaped the first stage. 

For many proteins, especially glycoproteins, the physical characteristics, particularly the hydrophilic nature of Toyopearl HW resins, improve mass and activity recovery rates. Toyopearl HW media do not adsorb proteins, as conventional gels can, and thus do not interfere with sample recovery (39). 

Hysteresis effect The hysteresis effect is a retardation of the strain when a material is subjected to a force or load. Figure 2-12 are examples of different hysteresis recovery rates. 

Electrodialysis is a well-established technology but suffers from poor recovery rates and is very susceptible to scaling problems. (A derivative, EDI, however, is able to overcome these problems, albeit at a higher capital cost.)... 

Tap water. As city water, mains supply, and the like, tap water is typically under 1,000 to 2,000 ppm TDS. It requires an RO plant operating with an applied pressure of 150 to 300 psig and permeate recovery rates of 80% down to perhaps 50% of the RW supplied... 

Brackish water. Usually associated with salty water, brackish water TDS levels range from 2,000 to 20,000 ppm or more. Most industrial sources of RW supply may be well water, surface waters, or the like, but do not specifically have to contain high levels of sodium chloride. The RO applied pressure required is from 250 to 600 psig, and the permeate recovery rates are typically 60% down to perhaps 40%. There is a tremendous variety in so-called brackish water sources, and correct membrane selection and other design criteria are critical to manufacturing an efficient RO plant. 

Seawater is increasingly being used as a RW source for industrial water, drinking water, and boiler FW because of both a lack of suitable alternatives in some areas of the world and constantly improving RO water production-cost ratios. Seawater TDS levels vary around the world, from approximately 36,000 to more than 45,000 ppm. As TDS levels increase, the RO applied pressure requirement typically may increase from 800 to 1000 psig or more to maintain recovery rates (usually 25-35%). 

Concentrate recycle RO plants allow some of the brine reject water to recycle back through the plant, which improves the permeate recovery rate. (The reduced flow of brine reject water does of course have a proportionally higher TDS level.) Various types of high pressure, corrosion-resistant pumps are used, including multistage, centrifugal and plunger pumps, each with their own benefits and area of application. 

Electrodialysis is a particularly economic process for low-salinity waters when compared to RO because, although the initial capital cost may be 10 to 15% higher, it generally requires no pretreatment, it produces a higher recovery rate (around 80-85%), it has a lower operating and maintenance cost, and the membranes last twice as long (up to 10 years). 

This article provides information from a report from APME, which shows that recycling and recovery rates have declined since the early 1990 s. The report calls for an expansion in incineration - but not recycling - capacity. Brief details are given. 

Figure 7. Slow inactivation of Na channels is potentiated by STX. The graph shows the time required for the recovery of Na channels to an activatable state after a long (1 sec, +50 mV) inactivating depolarization. When tested by a brief test pulse, control currents (A) recovered in a fast (r = 233 msec) phase. Addition of STX (q, 2 nM, which approximately halved the currents with no inactivating pulse) approximately doubled the fraction of currents recovering in the slow phase and also increased the time constant of slow recovery. The fast recovery rate was unaffected. (Reproduced with permission from Ref. 47. Copyright 1986 The New York Academy of Sciences).

Because it is a small protein, the factor IX molecule passes into the intravascular and the extravascular spaces. Therefore, the volume of distribution of recombinant factor IX is twice that of factor VIII. Consequently, 1 unit of factor IX administered per kilogram of body weight yields a 1% rise in the plasma factor IX level (0.01 unit/mL, or 1 IU/dL). Thus 1750 units of factor IX provides an incremental increase of 50% of normal (0.5 unit/mL, or 50 IU/dL), that is, 1750 units/70 kg x 0.01 unit/mL (1 IU/dL).12 Additionally, the recovery rate with recombinant factor IX is 20% lower than that with the plasma-derived products. Therefore, initial and subsequent maintenance doses should be adjusted accordingly. 

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