Batch process

A batch process is understood to mean a process that leads to the production of defined quantities of substances by subjecting quantities of input materials to an ordered sequence of process activities using one or more facilities within a defined period of time. (IEC 60050-351)

Different processing methods make different demands on the associated procedures and technologies. In some processes, it is better if only the same partial step is always carried out continuously. Other areas require, for example, better traceability with regard to individual batches. In these cases, the so-called batch process is ideal for implementation.

What happens in the batch process?

The batch process is part of the field of process engineering. First, a reaction vessel is completely filled with the starting materials, the so-called reactants. Finally, adding a catalyst starts the reaction that turns the reactants into products. The concentration of the reactants steadily decreases while that of the products steadily increases, similar to the two containers in an hourglass. As soon as the reaction is complete, the products are removed and sent to the downstream process (i.e. further processing). Before it can be used again, the reaction vessel may have to be cleaned, after which the process starts all over again.

Examples of the batch method

Batch processes are used particularly frequently when it comes to the production of powders or granules. The demand for the traceability of individual batches made a process necessary in which the end product is not produced continuously, but in individually separated quantities, for which the starting materials used can be noted in each case. Typical sectors for which the batch process is of great importance are:

• Pharmaceutical industry: Manufacture of medicines, dietary supplements, etc.
• Food industry: Production of baby food, for example
• Beverage industry: Separation of cloudy matter from clear fruit juices
• Fermentation processes (e.g. brewing beer)
• Other fermentation processes (e.g. biogas production)

What is the fed batch process?

The fed batch process is a special variant of the batch process. The reaction vessel is initially only partially filled with starting materials. The reaction is then also set in motion; the reactants gradually react to form products. However, further reactants are now added during the process until the reaction vessel is completely filled with products.

This variant offers advantages above all when the reaction speed is to be controlled. The addition of starting materials can be used to determine how quickly the reaction proceeds. This can play a role, for example, if a lot of heat is generated during the reaction that has to be dissipated. In addition, the concentration of toxic by-products can be kept significantly lower. The amount of products can also be higher compared to the batch process, since the amount of reactants is not tied to the reaction vessel.

What is the semi-batch method?

The semi-batch process is a special form of the fed-batch process. Here, too, the reaction is started after a certain amount of initial reactants. Further starting materials are then added, which are continuously converted into products. In contrast to the fed-batch process, however, there are fewer control options for the supply and removal of reactants and (by-)products. For this reason, it is used less frequently overall than the (fed) batch process.

Batch systems from PURPLAN

Batch systems are an indispensable technology for manufacturing various products in industry. The requirements for the systems can be diverse, depending on the industry and the desired product. With PURbatch, PURPLAN offers individual mixing systems for every need. Both the fully automatic weighing and mixing of the components and the dosing can be adapted to the needs. In addition, the vacuum and pressure can be adjusted manually. Convince yourself of the excellent quality of the fully automatic mixing stations from PURPLAN and arrange a non-binding consultation now: Contact us!