Pruess Extraction Plants

For the extraction of desired components from plant parts

Whether continuous extraction or batch extraction, whether single-stage or multi-stage, we design every system optimally.

Pruess GmbH excels in the realm of building and commissioning extraction plants, offering additional qualification services when necessary. These extraction plants are frequently employed in industries such as food and pharma to extract desired components from plant materials.

Our engineers have a broad range of experience in installing extraction plants, from compact 50-liter pilot plants to large-scale industrial facilities spanning several cubic meters. Whether it’s continuous or batch extraction, single-stage or multi-stage, each plant is designed with optimal efficiency in mind. We always consider your ideas and requirements, as well as the unique characteristics of the chosen bio-materials.




Extraction Plants

Pruess GmbH - Extracor

Areas of application for extraction

Extraction is a separation process in which one or more components are dissolved, i.e. extracted, from a mixture of substances or biomaterial by the addition of a solvent. The product is a solution of the desired compound, such as oleoresins, colorants, flavorings or active ingredients. This extract can be further processed. The usual method is to concentrate it using an evaporation plant, which we can also design and build.

Alternatively, the extraction process is used to remove an unwanted component from a solid such as tea, as is the case with decaffeination, for example.

Different extractors are required depending on the proportion and solubility of the ingredient to be extracted as well as the nature and quantity of the solid. The most common forms are continuous and batch extraction.

Pruess Extraction Systems

For a batch extraction, the extractor is loaded with the raw product in several batches. Depending on the number of extractors, extraction takes place in a single-step or multi-step process. Depending on the design of the process, maceration can be carried out in co-current, counter-current or simple.

The advantage of batch extraction is the lower cost of the plant. However, more personnel are required for operation.

The decision as to which system is better to use depends on many factors and must be considered individually for each application.

The batch extraction plants and batch extractors from Pruess GmbH are optimized for maximum functionality and always adapted to the respective application abd your need. The economical operation of the systems while achieving the best possible yield in the respective extraction process is guaranteed on the one hand by the process adapted to the product and on the other hand by the automated, and therefore reproducible, process sequence.

The intelligent piping in particular enables individual operation of the batch systems, which can also be easily adapted to other extraction parameters such as temperature and solvent.

All Pruess extraction systems can be operated in different modes, i.e. either in single or multiple-stage mode (single or multi-stage) and with or without recirculation of the miscella. Their easy-to-clean and sterilizable design enables the extraction units to be used in a permanently hygienic manner.

Last but not least, the qualifiable design is another major advantage of Pruess batch systems.

Batch Extraction

Continuous Extraction

The growing need to process larger quantities of the same raw product, as is the case with tea or bark, for example, led to the development of continuous extraction plants. These plants, which are particularly common today for the extraction of soybean oil, have achieved a high degree of perfection and efficiency in recent decades.

Even in areas with smaller quantities, it can make sense to use continuous systems instead of batch extractors. Depending on the costs for products, educts and personnel, a continuous solution should be considered from above 50 cubic meters per day. The design of the extractor is essentially determined by the properties of the product to be extracted. The nature and type of preparation of the raw product naturally also have a major influence on the performance and yield of any extraction plant.

The experts at Pruess GmbH will be happy to assist you in deciding whether a batch or continuous system is the more suitable solution for your application.

In continuous extraction plants today, the vast majority of raw materials to be processed are extracted using the percolation principle. The Pruess ring extractor (REX) also works according to this prooved principle, which most consumers will be familiar with from filter coffee. Its advantages include its compact, well-engineered and closed design, its small footprint, low operating costs, flexible operation and, last but not least, the fact that the extractor is easy to clean.

The Pruess ring extractor consists of a one-piece rotor whose annular space is divided into cells by radial partitions. Each cell is equipped with a bottom that can be folded away downwards, which ensures a completely calm pouring process during extraction. The extraction agent percolates through the extraction material layer, enriches itself with the components to be extracted, is simultaneously subject to self-filtration, passes through the sieve bottom, collects in chambers separated by weirs in the lower part of the extractor and is pumped back up to the extraction layer of the subsequent cell (counterflow principle). At the end of the cycle, the extraction residue falls into a discharge chute and is continuously discharged by a screw conveyor, supported by an additional pneumatic forced discharge system for some products.

Before a product change, built-in washing nozzles clean the individual cells and sieve bottom flaps of adhering extraction residue. The bottom of the extractor is designed in such a way that no residue is left behind. This means that different products can be processed in the system in alternating sequences without cleaning work leading to considerable downtimes.

Pruess Continuous Extractor “REX”


When designing the extraction plant, we take into account your ideas and requirements as well as the special features of the selected organic materials.