Flowsheets Types

Windscale II plant in the UK. In this the uranium and plutonium are back-extracted together in a first cycle of decontamination. They are then separated in a second cycle of solvent extraction and independent back-extraction. The factors affecting the choice of flowsheet type have been reviewed and criticality control is an important consideration in the process design.286... 

In Chapter 7 we showed that the esterification of acetic acid with different types of alcohols (C1-C5) can be classified into three types of flowsheets (types I-III), which were shown in... 

Flowsheet Type System Fraction of Sign Reversal Nonlinearity Measure Overall Assessment ... 

Flowsheet Type System Two-Temp. Control One-Temp., One-Comp. Control ... 

Figure 3. Flowsheet for a maximum conversion type refinery.

A separate table such as the example in Table 15-2 is prepared for each line designation. Each valve is assigned a designation on the flowsheets and explained in this table. The pipe, valves, and fittings table can sp( acceptable valves by manufacturer and model number, by a generic description, or by a combination of the two as shown in the example. It should be pointed out that Tables 15-1 and 15-2 are examples from American Petroleum Institute Recommended Practice (API RP) 14E and are illustrative only. There are almost as many different formats for pipe, valve, and fip "" tables as there are companies, and these examples are in no manner ty or recommended. Often, for. simphcity, valve types are not described i pipe, valve, and fittings specifications but on separate sheets for each. ... 

Used to present the heat and material balance of a process. This may be in broad block form with specific key points delineated, or in more detailed form identifying essentially every flow, temperature and pressure for each basic piece of process equipment or processing step. This may and usually does include auxiliary services to the process, such as steam, water, air, fuel gas, refrigeration, circulating oil, etc. This type of sheet is not necessarily distributed to the same groups as would receive and need the piping flowsheet described next, because it may contain detailed confidential process data. 

The two types of lines on a flowsheet are (1) those representing outlines and details of equipment, instruments, etc., and (2) those representing pipe carrying process or utility liquids, solids, or vapors and electrical or instrument connections. The latter must be distinguished among tliemselves as suggested by Figure 1-21. 

Figure 1-20A. Special types of descriptive flowsheet symbols.

The various items are usually numbered by type and in process flow order as set forth on the flowsheets. For example ... 

Current technolog) allows the use of computer programs and data bases to construct an accurate and detailed flowsheet. This may be a process type diagram or a piping and mechanical/instrument diagram, depending on the input. See Figures 1-9, 1-10, 1-18A and 1-18B. 

Extractants derived from the carbamoylmethylphosphoryl moiety (CMP) were studied in the phosphonate, phosphinate, and phosphine oxide classes. Our studies focused on dihexyl-N,N-diethylcarba-moylmethylphosphonate, DHDECMP, hexyl hexyl-N,N-diethylcarbamoyl-methylphosphinate, HHDECMP, and octyl(phenyl)-N,N-diisobutylcarba-moylmethylphosphine oxide, 0D[ IB]CMP0. The three types of CMP extractants were compared on the basis of nitric acid and extractant dependencies for Am(III), solubility of complexes on loading with Nd(III) and U(VI), and selectivity over fission products. On the basis of the above data two conceptual flowsheets were developed. The first flowsheet involves the extraction of all of the actinides from HLLW using 0.4 M 0D[IB]CMP0 in DEB. The second flowsheet involves the extraction of all of the actinides from dissolved spent LWR fuel using 0.8 M DHDECMP in DEB. 

By way of an example, one may consider the case of hydrometallurgical reactors. Leaching is the most important of the different unit operations, and is prominently placed and assigned due emphasis in a typical hydrometallurgical process flowsheet. A representative list of the various types of reactors used for agitation leaching is given in Table 1.21. 

Acylpyrazolones (24) also form neutral /3-diketonate-type complexes suitable for extraction of a range of metals into organic solvents and have been considered171 as alternatives to LIX 54 for use in ammoniacal leach circuits. Although they are stronger extractants than LIX 54,4,172 the low solubility of their metal complexes has limited their usefulness in Cu recovery.171 The structurally related diazopyrazolones (25) have pHi/2 values, ca. 3.7, and their chemical stability on contact with ammoniacal feeds meets the requirements of the flowsheet outlined above, but their very intense colors may restrict their use as commercial extractants.173,174 The bulk of the arylazo... 

The type of collector and flowsheet configuration play an important role in gold recovery from these ores. With a flowsheet that uses bulk Cu-Pb flotation followed by Cu-Pb separation, the gold recovery is higher than that achieved with a sequential Cu-Pb flotation flowsheet. In laboratory tests, and Aerophine collector type, in combination with xanthate, had a positive effect on gold recovery as compared to either dithiophosphate or thionocarbamate collectors. Table 17.10 compares the metallurgical results obtained with an Aerophine collector to those obtained with a dithiophosphate collector. 

---