Aspen Plus

Characteristics ASPEN PLUS Chemcad II Desiga-II Hysim Pio-11 Oiiasilin Span SPEEDUP... 

The optimization of empirical correlations developed from the ASPEN-PLUS model yielded operating conditions which reduced the steam-to-slurry ratio by 33%, increased throughput by 20% while maintaining the solvent residual at the desired level. While very successful in this industrial application the approach is not without shortcomings. The main disadvantage is the inherent assumption that the data are normally distributed, which may or may not be valid. However, previous experience had shown the efficacy of the assumption in other similar situations. 

ASPEN-PLUS Introduction Manual, Aspen Technology Inc., Cambridge, Massachusetts. 

ASPEN-PLUS Introductory Manual, Aspen Tech. Inc., Cambrdige, MA SAS Manual, SAS Inc. 

Aspen Technology, Inc. Aspen Plus, Aspen Custom Modeler, Dynaplus, Split, Advent, Adsim. Cambridge, MA (1998). 

The Aspen Properties implementation of the NRLT-SAC method is available as a template. aprbkp file to license holders of Aspen Properties or Aspen Plus release 12.1 or above, by contacting Aspen s support centre or regional sales offices. The template is distributed with an Excel interface to simplify the data regression process and is suitable for non-expert users of Aspen Properties. Numerous Excel templates are available for data analysis and design calculations, based on the NRTL-SAC model. 

Venkataraman, S., Chan, W. K. and Boston, J. F., 1990, Reactive distillation using Aspen Plus. Chem. Engng Prog. 8, 45-54. 

Aspen Plus Steady-state process simulation www.aspentec.com... 

At the core of many of these algorithms for solvent substitution is a method for predicting the properties of proposed molecules, given only the molecular structure. Much work has been done in this area alone, and several programs have been developed to guide this process. Some of these programs are listed in table 9.1. Additionally, process simulation software such as Aspen Plus contain several different approaches for the prediction of properties from molecular structure. 

MH Locke, "The ASPEN PLUS Pressure Relief System Technical Details and Benchmark Results", Attachment 69 Minutes of 17th DIERS Users Group Meeting, Orlando, January 1995... 

To study different operating conditions in the pilot plant, a steady-state process simulator was used. Process simulators solve material- and energy-balance, but they do not generally integrate the equations of motion. The commercially-available program, Aspen Plus Tm, was used in this example. Other steady-state process simulators could be used as well. To describe the C02-solvent system, the predictive PSRK model [11,12], which was found suitable to treat this mixture, was applied. To obtain more reliable information, a model with parameters regressed from experimental data is required. 

Fig. 8.3-2. Aspen-Plus flow sheet used for simulation comparisons The equipment list is reported in Table 8.3-1.

Venkataramkan. S., W.K. Chan, and J.F. Boston Reachve Disiitlaiion Using ASPEN PLUS," Chem. Eng. Progress. 45 (August 1990). 

Engineers may ask, When I plan to use a simulation package such as ASPEN PLUS , PRO II , UNISIM , or even the CD provided with this book, why should I be concerned with simpler, less accurate methods of phase equilibria and diagrams If I m concerned with accuracy, why not use two prediction packages and compare the result ... 

As a consequence, corporations operating PUREX plants have been using sophisticated process simulation codes, including the PAREX code in France (45-47), SpeedUp (Aspen Plus) in the UK (48), and SIMPSEX code in India (49-51). Argonne Model for Universal Solvent Extraction (AMUSE) code in the United States was contrived not only for PUREX, but for UREX+ processes (52), which will be mentioned later. In Japan, similar efforts have also been made (53-55). 

ASPEN PLUS User s Guide (1994), Aspen Technology Inc., 251 Vassor St., Cambridge, MA 02139 (1994). 

The example CO2 capture process, shown in Figure 8 as an Aspen Plus EO model representation, is part of an ammonia plant. Designed to scrub CO2 from ammonia synthesis gas, it includes an absorber and two solution regeneration columns, one stripping the rich, C02 laden solution leaving the absorber to semilean concentration of absorbed CO2, and the other cleaning the solution even further to lean solution... 

Figure 8 Aspen Plus EO model for an MDEA/PZ C02 capture unit.

S 2] With the steady-state process simulator Aspen Plus , thermodynamic models for the sulfur-iodine cycle given in [132] are combined with chemistry models which describe the dissociation and precipitation reactions. 

These examples underline the fact that macro-scale process simulation tools such as Aspen Plus will have to be supplemented by micro-type unit operations as introduced by the FAMOS initiative which consider the location of a fluidic cell in the device and does not assume a perfect mixing, piston flow or uniform heat transfer coefficient [13]. 

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