What are the processes of mixing?

Mixing is a unit operation aimed at achieving homogeneity in our tank. When our goal is mixing, our primary criterion is homogeneity. The better the homogeneity, the better the mixing. And it is true in the academy if you want to characterize mixing. But in the industry, mixing is not the goal. It is a vital tool used to generate interaction between the materials, advancing them through the various stages of a manufacturing process. This can include chemical reactions, purification, solute handling or liquid handling and release. And when we’re talking about a reaction, this can be a chemical reaction, catalytic reaction, or fermentation. When talking about purification or separation, we’re talking about distillation, evaporation, filtration, crystallization, emulsification, separation phases, and absorption. Where handling is concerned, we’re talking about molecule screening. With formulation, we’re talking about adding solids and generating mixing solutes, mixing of solids in the liquid phase. For manufacturing products like creams, oils or syrups, we’re talking about high-shear rate equipment for emulsification.

For every one of them, there are models that explain the chemical affinity, the connection between the chemicals in the process, and some knowledge about thermodynamic equilibrium, solubility, reaction rates, and diffusion between the materials. All take into consideration the chemical connection and interaction between the chemicals once they are connected. They will create conditions that allow molecules to come into close proximity and interact, facilitating progress according to the process.

Now, we generate these kinds of interactions with mixing. The main goal of the mixing is to generate homogeneity in the tank. Depending on what the process requires, we need some level of interaction between the materials, we will generate the mixing according to the interaction required. The tank is typically cylindrical, equipped with baffles, and when the agitator’s velocity is transferred to the fluid, it initiates flow. The flow’s intensity and direction are determined by the energy I am providing and the direction of the flow we’re generating with the geometry of the impeller. The flow will start to move, and according to the intensity of the flow, this should be laminar or turbulent. In a laminar regimen, there is a lack of mass transfer because the layers of fluid remain separate, making it difficult to have mass transfer. Any mass transfer that does occur takes time. A turbulent regimen generates fluid elements according to the intensity and direction of the flow. And for the geometry, we are generating fluid elements. According to Kolmogorov’s theory, fluid elements, mainly on the order of microns, interact within themselves primarily through molecular diffusivity. These fluid elements move rapidly throughout the tank, a process typically associated with convective mass transfer coefficients. And we need to ensure that the pathways of these fluid elements moving within the tank facilitate the transfer of materials and achieve homogeneity, which is essential for optimal quality, productivity and operation.

Mixing, primarily in the liquid-liquid phase, is governed by momentum balance equations. These allow us to understand and calculate velocity, from which we can determine mixing parameters such as mixing times, shear rates and more. These parameters influence factors like drop size, solid distribution, temperatures in different zones, and deviation concentration, ensuring a process with high productivity, quality and efficient operation.

what is the mixing process?

This is a multi-dimensional phenomenon that creates an environment that we’re providing for our materials to interact. This interaction enhances chemical affinity to our reaction, crystallization, and other processes we’ve previously discussed.

What is the difference between chemical blending and chemical mixing?

Chemically, blending and mixing are the same thing; there is no conceptual difference in their roles within a process. Both involve adding materials to a sterile vessel and agitating them to create conditions favorable for interaction. This process aims to meet specific requirements and achieve high-quality results in both operation and product quality.

What is the goal when you mix materials?

The answer is simple, we mix materials to generate a process that will be acceptable for us from a business point of view. By doing so, we enhance the company’s profitability, ensuring revenues exceed expenses. This supports ongoing operations and the workforce while also providing sufficient margins for reinvestment in R&D. Such investments aim to elevate the quality of life globally. This is our mission, so the interaction between the materials must be well-suited to the process.

What is the formula for chemical mixing?

There is no formula. Mixing is a complex unit operation. So, it cannot be fully captured by a set of empirical equations. Mixing is a broad field that happens at multiple levels – micro, meso and macro mixing scales – each involving unique interactions and complexities. Due to its intricate nature, outcomes cannot be predicted merely by visual inspection of the tank and impeller. Instead, accurate predictions require computational models and specialized software designed to represent the dynamic interactions within the mixing process. For over 25 years, VisiMix has been a trusted name in the market, well-established among leading companies in the pharmaceutical and chemical industries, among others. Our approach is to provide you with a license that allows you to generate numbers but also supports you through a structured training plan. This includes basic training, follow-up projects, and collaborative sessions to analyze results and plan future steps.

So, what is the formula for chemical mixing? It is complex. It is a compromise between chemical affinity and conditions provided by the mixing of the materials to interact. To address the complexities, we offer complete models on our VisiMix website. Here, you can review the main momentum balance, main mass transfer balance, and heat transfer balance. Additionally, you’ll find correlations and validations between our resource and the experimental results reported by papers in the academic and industrial fields.