Data extraction

Having discussed the way in which changes to the basic stream data can improve targets, an even more fundamental question now needs to be addressed. Before any heat integration analysis can be carried out, the basic stream data needs to be extracted from the material and energy balance. In some cases, the representation of the stream data from the material and energy balance is straightforward. However, there are a number of pitfalls that can lead to 

Consider now the basic principles of data extraction for heat integration. 

100°C is degraded to 70°C. The overall heat exchange can never benefit by such degradation. 

Enforced matches. There are often some features of the heat exchanger network that the designer might wish to accept as fixed. This is often the case in retrofit. For example, a match between a hot and a cold stream might exist that is considered to be already appropriate or too expensive to change. If this is the case, then the part of the hot and cold stream involved in the enforced match should be left out of the analysis and added back in at the 

Heat losses. For the majority of cases, heat losses to the environment from hot surfaces will be small compared to other heat duties and can be neglected. Occasionally, it might be necessary to accept a significant heat loss and to account for it in the energy balance. If the heat loss is from a cold stream, then it should be included with the process duty, as the heat loss must be serviced either from heat recovery or hot utility. If the loss is from a hot stream, the heat loss can be accounted for by splitting the stream from which the heat loss is occurring into two components the process duty and the heat loss. The heat loss should then be left out of the analysis if the heat loss from the hot stream is to be accepted. 

FIGURE 9.1. Process flow diagram for the example energy targeting. 

A heat recovery targeting assessment starts with data collection for process streams based on existing process design and operation conditions. When extracting operating data, the questions are as follows What time periods of data should be extracted What feed rate and compositions should be used as the basis The idea is to select the operating conditions that reflect the most common operation in terms of feed rate and product yields. On this basis alone, the benefit calculation has meaningful representation. Therefore, two criteria could be satisfied for data extractions  

There are two kinds of process streams in the context of the energy targeting, namely, hot and eold streams. Hot streams are those whose temperature reduces and 

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Nuclear Data Sheets, Academic Press, San Diego, Calif., TvaluatedNuclear Structure Data File (ENSDF), a computer database of nuclear stmcture data evaluated by an international network of evaluators, is maintained at the National Nuclear Data Center, Brookhaven National Laboratory. NUDNTis a computer database of decay data extracted from the ENSDF. 

The data points from SAIC s data base were already stored in CARP files. Data extracted from the CPI data resources were also entered into CARP files for storage and organization of the data points by their relevant taxonomy levels. 

Data encoding The assignment of codes and identifiers to data extracted from plant records so that failure rates may be readily calculated. 

Data extracted from BS 499 Part 1 (1965). Complete copies of this standard can be obtained from The British Standards Institution, Information Department, Linford Wood, Milton Keynes, MK 14 6 LE. 

Now consider die experimental results shown in Figure 85. From these graphs data can be extracted and presented in tabular form. Table 8.4 presents some data extracted from Figure 85, along with other data (for carbon dioxide) that were not shown in die Figure. 

The pilot plant stage Is vital in the scale-up of any new resin process, and in this paper we discuss the design philosophy of pilot plants and then describe two fully Instrumented and computer data logged reactors. Some indication is given of the use of the extracted data for both modelling and scale up. Both controlled and data logged parameters are tabulated and an example of data extraction for heat balance is illustrated. 

Our whole package Is In-house specified and written, and while we are aware that complete packages to data-log are now available, we feel confident In showing this as an example of a high technology state-of-the-art system. Examples of data extracted for heat balance, and comparison to simple models can be demonstrated. 

Statishcal criteria of Eq. (24) are too good the standard deviation, which was created on the basis of different measurements by various authors, is much less than even the experimental error of determinahon. This could be due to mutual intercorrelation of descriptors leading to over-ophmistic statistics [18]. Another reason may be the lack of diversity in the training set. The applicahon of the solvation equation to data extracted from the MEDchem97 database gave much more modest results n = 8844, = 0.83, root mean square error = 0.674, F = 8416... 

As an example, Fig. 17.4 presents the ligand efficiency of 107 compounds active against human 5-hydroxytryptamine lA receptor (data extracted from GVKBIO). Compounds A and B have different potencies (IC5oA= 12.2pM and IC5oB= 1.0 pM) and properties (MWA=244, HAA=18, CLOGPA=2.8 and MWB=294, HAB=22, CLOGPB = 4.1), but display a similar LE of 0.37. 

IC5o=1.0pM, MW=294, HA=22). Open circles indicate compounds with R05>1 (at least one parameter from Lipinski s Rule-of 5 is out of range). Activity data extracted from GVKBIO. 

Data extracted from Certificate for CRM RTH 912, Loess Soil from Switzerland, produced by Pro-mochem GmbH, Germany, with permission). All units mg/kg... 

Further progress in understanding membrane instability and nonlocality requires development of microscopic theory and modeling. Analysis of membrane thickness fluctuations derived from molecular dynamics simulations can serve such a purpose. A possible difficulty with such analysis must be mentioned. In a natural environment isolated membranes assume a stressless state. However, MD modeling requires imposition of special boundary conditions corresponding to a stressed state of the membrane (see Refs. 84,87,112). This stress can interfere with the fluctuations of membrane shape and thickness, an effect that must be accounted for in analyzing data extracted from computer experiments. 

If indirect heat transfer is used with a large temperature difference to promote high rates of cooling, then the cooling fluid (e.g. boiling water) is fixed by process requirements. In this case, the heat of reaction is not available at the temperature of the reactor effluent. Rather, the heat of reaction becomes available at the temperature of the quench fluid. Thus, the feed stream to the reactor is a cold stream, the quench fluid is a hot stream, and the reactor effluent after the quench is also a hot stream. This was discussed under data extraction in Chapter 19. 

When considering heat exchanger and network design, the important issue of data extraction was highlighted, as lost opportunities can result from poor data extraction in heat exchanger and network design. Similarly, there are fundamental issues associated with data extraction for the design of water systems. 

Figure 3.1. Changes of Zn activity in 10 Colorado soils with pH (data extracted from Ma and Lindsay, 1990)...

Figure 3.3. Changes of Cd speciation in soil solutions of Cd nitrate-treated Domino soil from California (data extracted from Candelaria and Chang, 1997)...

Figure 3.4. Effects of phosphate levels on Cd and Zn solution speciation in California soils that received sludge application (data extracted from Villarroel et al., 1993)...

Figure 3.5. Effects of Cl concentrations (NaCl or CaCl2) on Cd solution speciation in a California soil (data extracted from Bingham et al., 1983)...

Figure 7.5. The AB-DTPA-extractable Cu and Zn in a semi-arid soil from Colorado after termination of five excessive biosolids applications. Open circle (fine, smectitic, mesic Aridic Argiustolls) and open triangle (fine, smectitic, mesic Aridic Paleustolls) represent control soil without biosolid application, while solid circle and solid triangle indicate biosolid applications (data extracted from Barbarick ad Ippolito, 2003)...

Figure 8.1. The accumulation of trace elements in two Californian soils. The soils received four-year sludge applications at the rate of 0, 22.5, 45, and 90 tons ha-1 year 1. Domino loam soil, fine-loamy, mixed, thermic Xerollic Calciorthid Greenfield sandy loam soil, coarse-loamy, mixed, thermic Typic Haploxeralf (Data extracted from Sposito et al., 1982)...

Table 9.1. Global industrial age annual production of selected trace elements and heavy metals in 1880, 1900, 1950, 1990 and 2000 (million tons) (Data extracted from Han et al., 2002a, 2003b)...

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