While we were investigating which process simulation software to use for our project, one of the options we were investigating was called SuperPro Designer by Intelligen [1]. This made it towards the top of the list because one of its listed features is that it has the capability to model a convective dryer. Below is an example of SuperPro Designer’s capability to simulate process equipment!

From the above example simulaton, we can tell that SuperPro has many similar features to Aspen Plus. Both simulators are capable of handling reaction thermodynamics, they are both capable of handling solids feed and product streams, they can both even handle convective drying! Ultimately, we ended up choosing to use Aspen Plus because all members of our ChemE team have the ability to access it, while we only have very limited access to SuperPro Designer.

Relationships:

[1] Intelligen, Inc., “SuperPro Designer Product Features,” Intelligen, SuperPro Designer, SchedulePro, EnviroPro, https://www.intelligen.com/products/superpro-product-features/ (accessed Feb. 20, 2025).

[2] Intelligen, Inc., “Wastewater Treatment and Pollution Control,” Intelligen, SuperPro Designer, SchedulePro, EnviroPro, https://www.intelligen.com/industries/wastewater-treatment/ (accessed Feb. 21, 2025).

Our MechE Team has been diligently working on our Ansys Fluent simulation and all its required subcomponents. One piece of this that they wanted to show off was the CAD model of the ductwork that they have been working on. This is an image of the Solidworks model being used in Ansys fluent showing some of the boundary conditions.

This is one part of the major system that will be modeled in Ansys fluent by our MechE team. This piece of ductwork serves to show that the best way we have figured out how to simulate airflow is by using the volume of fluid inside the ductwork as the volume of air that needs to flow.

Last week, Dry Guys conducted a site visit to GreenTechnologies facility to run an experiment on the dryer for data collection! With the help of the operations team at GreenTechnologies, we were able to successfully collect the data we came looking for. The data collected will help us both construct our simulations and make them more accurate, which will enhance our recommendations to GreenTechnologies for optimizing their dryer. Below is an image of a couple of our team members actively collecting data from the site visit!

When using Aspen Plus to model any piece of equipment, there are certain assumptions that the software automatically makes to ensure that it will have the ability to converge to a solution.
For modeling a Convective Dryer, the assumptions that are made are as follows:
– The Dryer is adiabatic (no heat losses).
– The Dryer gas and its particles pass the dryer in plug flow.
– The particles are ideally mixed in the lateral direction.
– The moisture content and temperature are spatially constant in every particle.
– Intraparticle drying resistances are taken into account by applying the concept of normalized, single-particle drying curve of van Meel.

The other assumption that we are making is that the air is in a counter current and cross-flow configuration. Figure 1 depicts what counter current flow looks like in practice. Counter current flow is used to put the hottest air to the driest part of the product. Figure 2 depicts cross-flow in practice, and it is used because it provides the most efficient heating of the material. Combining the two diagrams would give you the air flow path that we are trying to model.

References:
[1] Aspen Plus V11 Help Menu. AspenTech, 2019.

As we dive deeper into simulating GreenTechnologies equipment, our ChemE team would like to share some more Aspen Plus information!

When setting up a unit operation in Aspen Plus seen in figure 1, you have to not only specify what streams are and where they are going, but also what is going on inside the unit, which can be seen in figure 2. In figure 2, some of the major options that we have to define are the dryer type, the gas flow, and the solids flow. For the dryer type, there are 2 options to choose from – shortcut or convective. They use the same type of model behavior, however the convective dryer is a much more rigourous model which requires more specified parameters from the user. We have chosen to go the path of the convective dryer to get a model that is closer to our experimental data. The flows are both choices that were made when the equiment was installed, and we have obtained GreenTechnologies’ equipment set up and input it into our model.

There is one more major tab that is important to getting a functional simulation. This is the Drying Curve tab under the dryer properties, which can be seen in figure 3. This tab specifies the target and equilibrium moisture contents, which are critical to recieving a working dryer. This tab also specifies the drying curve function and shape, which is something our Feedstock team will be determining in the lab soon.

References:

[1] K. I. M. Al-Malah, Aspen Plus: Chemical Engineering Applications. Hoboken, NJ: Wiley, 2022.

We would like to welcome everyone back from a lovely winter break! The Dry Guys are excited to hit the ground running and continue to work on our project.

We made a quick site visit to get some necessary dimensions of the dryer itself for modeling it in both Ansys CFD and Aspen Plus. With these dimensions we are confident that we can have working models soon and accurate models to follow!

References:
[1] cstock56, “Welcome back sticker – welcome back – discover & share gifs,” Tenor, https://tenor.com/view/welcome-back-gif-19477654 (accessed Jan. 16, 2025).