Scale-up of Chemical Processes

What are the main considerations when we talk about scale-up in transfer processes?
1. When you’re in the lab, you have very small equipment, whereas in a production environment you go from tens of liters to hundreds or thousands of liters; hence, you’re increasing the dimensions. If you want to have the same performance or the same mixing pattern, then you need to coordinate between the mixing parameters that will generate in small equipment to big equipment. So, if you’re working in the lab with low velocity, high probability it will be a laminar regime, whereas if we go to the next step with normal velocity and obtain a high Reynolds number, then we will be in a turbulent regime. When we’re working on different regimes of mass transfer mechanisms, we are at a completely different mixing scenario, which will generate deviations in our research. So take care. Try to work in the same regime.
for example –

2. The second point is supercritical. You go to production and people tell you, “Okay, you know, this is the equipment we will involve in the production.” And they told you, “but we don’t have enough raw material. But we will use this equipment; it will be a very good approach to use the same equipment with low volume.” 

And let’s assume there is the difference between liquid liquid mixing and solid liquid mixing. If you’re using the same equipment with a low volume and you’re using the same velocity in the low volume and big volume, then it is completely different mixing parameter. When you are using more volume, you need to allocate the RPM against the filling time and against the heat and mass transfer again because it will be different. If you go to a big volume, then a completely different distribution of energies occurs and maybe your universals will change. If you increase the volume, then you must adapt the mixing parameters to achieve good results.

The scale-up environment in the typical chemical industry is characterized by a non-well-known background of the process mechanism, which frequently results in a significant gap between laboratory and production results or between old and new facilities in the company. The scale-up and transfer of industrial technology activities are expansive and carry high risk. In both stages, raw material quality for the process and the process procedure are not modified. The only scope for experimenting with deviations is the mixing filed. Geometry and size changes in the equipment forces the process to progress at different rates than those run at lab-scale or in previous equipment, and should generate deviations in the quality of the produced materials and the operation and yield of the process.
Another concept that should be clarified during scale-up and technology transfer activities in the industry is “Good Mixing.” For the professional team in charge, good mixing is linked with homogeneity, high velocity (for instance, big vortex), and/or high shear rate. If mixing characterization is our main goal, then those criteria parameters are required. For scale-up and technology transfer where the mixing is a service, good mixing provides conditions to the process for good results in operation, quality, and yield at every step. Those conditions will avoid troubles and enable acceptable performance of the process. In one phrase, from Bentolila et al, “Good Mixing for industrial activities is the Mixing that Provides the Required Conditions for the Process.” Training videos for this concept have been developed.

VisiMix Video

The Influence of Mixing in the Process
New methodology using VisiMix software for the purpose of checking the influence of mixing in the processes.

VisiMix Demo Operation
Learning how to input data into the VisiMix software and get results the will help us understand the influence of mixing in our processes.

Lab Experiments
Learning how to set up the relevant experiments at the lab scale, to develop the processes from an engineering point of view.