When using the Scenario Tester to optimize a plant or find out how process changes could affect plant operation, you should ALWAYS gather as much operating plant data as possible and match those current plant operating conditions using ProMax. Matching plant data first is essential to the success of the plant analysis. The existing plant model allows you to verify the model and identify p ...

Reactor specifications vary depending on the Reactor Type, Reactor Configuration, and whether or not the Reactor is adiabatic. All Reactors require some specifications in the Reactor block dialog. The Reactor Type is a required specification. Choices are: Conversion, Equilibrium, Gibbs Minimization, Plug Flow, and Stirred Tank. To access available specifications in the Reactor block, firs ...

Depending on composition and pressure, multiple hydrate, water freeze out, or CO2 freeze out temperatures are possible. ProMax calculates up to three of these points. When only a single point is present, the solid is stable at all temperatures below that point. When three points are calculated, the solid is stable at temperatures between the Mid and High Temperature Hydrate/Freeze Points ...

One convenient feature in ProMax is the “What’s This?” help. You can get quick information on almost any parameter without having to access the main Help file. To get to the “What’s This?” help from within the ProMax Project Viewer, Project Options, or Environment dialogs do one of the following: A) Right click on the cell and se ...

The Vapor Pressure Analysis in ProMax returns values for both Reid and True vapor pressures. The calculated True Vapor Pressure of the stream is based on ASTM D2889-95a(2000) Standard Test Method for Calculation of True Vapor Pressures of Petroleum Distillate Fuels. True Vapor Pressure is the pressure of the vapor in equilibrium with the liquid at 100 F (it is equal to the bubble point pr ...

ProMax includes a number of aliases for many of the available components. Depending on the Classification used when selecting components, a single compound might be named in different ways. You may choose the Classification that represents what you would prefer to see in the stream information. Following is an example using i-Butane:

• The Chemical Abst ...

There has been a question concerning the temperature coming out of the rich amine flash in ProMax. Often when a higher pressure liquid stream is flashed to a lower pressure some vapor is generated and some cooling occurs, however, this is not always the case. Instead, when the pressure of a rich amine stream is reduced, a small amount of dissolved hydrocarbon and acid gas is flashed off a ...

There are several definitions of trayed column flooding, and a number of correlations used to calculate flooding. Fraction Flooding in ProMax is calculated by Fair’s correlation which is generally conservative and includes both jet and downcomer flood data in its development. This correlation is described in Perry’s Chemical Engineers Handbook, 6th ...

Ammonia present in the rich feed to an amine stripper, even in the ppm range, tends to build up in the upper section of the stripper between the condenser and the rich amine feed leading to operating problems. Simulators such as ProMax which can model amine units reflect the operational problems as difficult convergence of ...

Hydrogen Sulfide (H₂S) is an interesting species. 

It has the characteristic odor of rotten eggs that I am sure you have smelled.  What’s interesting, though, is that this smell is only apparent in low concentrations.  Some people can smell this in as low of a concentration as about 4 ppb (parts per billion). ...

When setting up the specifications for a distillation column with a partial condenser and reboiler, the one item that most people in operations can tell you is the temperature in both the condenser and reboiler. This, however, is not necessarily the best information to use as the initial guesses in setting up a simulated distillation column. The two simplest specifications for ProMax colu ...

Kohl (1997) contains excellent information concerning trayed vs. packed columns for gas treating applications. Some information you will find in this text includes the following:

1. Bubble-cap trays and raschig ring packings were once commonly used in amine plant absorbers and strippers, however, modern plants are generally designed to use more effective ...

ProMax includes an extensive library of examples to aid the user in setting up a plant model. It is much simpler to start with an example and modify the inlet conditions and equipment operating parameters than it is to start a model from scratch. Examples representing almost any type of amine unit are available. In addition, the examples include a number of dehydration unit configurations ...

A number of correlations are available for predicting pressure drop and liquid holdup in multiphase flow through a pipeline. None of the available correlations is 100% accurate. The GPSA Engineering Data Book, 12th edition (2004), emphasizes the complexity of multiphase flow and points out that “errors in calculated two-phase pressure drops in the order of plus or minus twenty p ...

The 2.0 Version of ProMax includes a number of multiphase flow correlations in addition to the original Correlations included in the 1.2 Version. The original correlations were: Beggs and Brill, Dukler et al, Duns & Ros, and Orkiszewski. New correlations are: Aziz-Govier-Fogarasi, Lockhart-Martinelli, Lockhart-Martinelli Modified, Mandhane-Gregory-Aziz, OLGAS 2-phase, and OLGAS 3- ...

Although you can model any column (for example an amine absorber) using real stages, ideal stages are recommended because the column executes much faster and calculations are much more stable. If you are designing an amine unit, you should ALWAYS use ideal stages in the absorbers and strippers rather than real stages. If necessary, a real stage model based upon the ideal stage design can ...

When ProMax performs the freeze-out analysis calculations for a stream with a very low water content (e.g. dehydrated natural gas), the water dew point may not be calculated or the value may not be meaningful. In most cases a liquid water phase will not form, or will not be thermodynamically stable for the current conditions. Sublimation will occur instead of condensation, meaning that th ...

Part Per …. Dallas?

Some people get so caught up with the specifications that are handed to them or expected of their plants that they lose track of what they really mean. There is very little to put these numbers to a scale that can be really understood.

Here’s a quick try for both parts per million (ppm) and parts per billion ...

In certain cases there may be two hydrocarbon dew points as shown in the phase envelope below for a pressure of 1000 psia. The Dew Point Temperature reported by the Vapor Pressure Analysis in ProMax may not always be the highest dew point. A Phase Envelope Analysis should always be used along with the Vapor Pressure Analysis to check for retrograde condensation at operating conditions, an ...

Bryan Research and Engineering’s (BR&E’s) ProMax simulation software provides the user with ultimate flexibility in the use of measurement units. While several default unit sets are available for the operator to choose as his global preference, each individual Process Stream, Energy Stream or Unit Operation can be individually customized to mix and match units ...

With so many numbers that computer simulation programs can throw at you how do you know what numbers actually mean anything? One thing you have that a computer doesn’t is common sense. A computer knows only what it’s told, and for many programs it’s told to spew forth the total number of numbers that it can.

Here’s an example: 7 ...

One area where ProMax is getting a lot of attention is in Coal Gasification or IGCC processes.  Since IGCC involves partial oxidation rather than complete oxidation, the organically-bound sulfur is mainly converted to H2S rather than SO2.  The former is best removed from the crude Syngas exiting the gasifier by amine or physical solvent treating, which are well-modeled i ...

We at Bryan Research and Engineering continuously strive to improve upon our ProMax simulation software.  Did you know we have a development team constantly receiving requests from our clients, who have ideas which might improve the functionality of ProMax?  Those requests and ideas help shape future versions of ProMax, whether it be adding particular component interacti ...

Physical solvents are becoming increasingly popular as gas treating solvents, especially for coal gasification applications. ProMax accurately models a number of physical solvents such as DEPG (Coastal AGR), NMP or N-Methyl-2-Pyrrolidone (formerly Purisol), methanol (Rectisol), and others. The physical solvents tend to be favored over ethanolamine solvents when the concentration of acid g ...

Probably the most significant difference between ProMax and other amine sweetening simulators is that the ProMax Electrolytic ELR package uses the TSWEET Kinetic Model to predict the absorption of CO2 by amines. Thus the column hardware parameters (diameter, tray spacing, weir height) are very important to the model since these parame­ters are used to calculate the residence time ...