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Efficient cleaning - save energy, time and cleaning agents

The hygienic design of machines and systems and optimized cleaning processes can save cleaning resources and improve system availability. A mixing and dispersion technology specialist has developed various technical solutions for effective cleaning and tailors cleaning concepts to the user's individual requirements.

 Process plant for a printing ink manufacturer For a printing ink manufacturer, ystralinstalled a process system on whichcolor changes from black to yellowwithin measurable contamination limitsof 100 ppm can be realized.

The rules of hygienic design are aimed at completely cleaning and emptying a machine or system with the least possible use of cleaning agents. ystral machines and systems are increasingly designed according to these rules: Every flange, every seal of a mixer or disperser is designed in a way that ensures easy and complete cleanability - without gaps, without threads, without hidden zones. Even areas such as the underside of a mixer flange can be cleaned shadow-free using special cleaning heads. In order to make cleaning processes as simple as possible and keep the time required for cleaning to a minimum, ystral integrates CIP technology directly into the system and, where possible, uses the conveying effect of the existing machines for cleaning - a separate pump is no longer required. This means that a dispersing machine operated in a circuit on a process tank can be used not only for processes such as suctioning, wetting and dispersing powder materials and for pumping out the finished product, but also for circulating the cleaning medium. For GMP-compliant cleaning, the flow speed of the cleaning medium must be at least 1.5 m/s in order to prevent the formation of sediment and generate sufficient turbulence. With ystral, regardless of the size of the system, the flow speed is generally even 2 m/s.

ystral also uses the conveying effect of the Conti-TDS disperser in its TRM100 tank cleaning machine, which enables a higher liquid throughput - up to over 50 m³/h - compared to other cleaning systems. The system has proven itself in practice, particularly when circulating the cleaning liquid in tank sizes between 5 m³ and 50 m³ and in applications that require a high jet pressure for effective cleaning.

In process engineering, tanks are often cleaned with cleaning agents at the end of a process. This takes time and the resulting cleaning waste has to be treated or disposed of. An efficient alternative with technologies from ystral is cleaning with recipe components: One option here is to save on liquid raw materials during the production of the batch, which are used to rinse out the system following pumping into a letdown tank. For example, pigments are left directly in the process and do not have to be separated from the cleaning agent. For successive batches with similar raw materials, cleaning is integrated into the process and then takes place at the beginning of the following process rather than at the end. Residues of the previously manufactured product are recycled in the following batch. During filling, they are washed out under high pressure - not with cleaning agents, but with recipe components from the subsequent batch. Cleaning waste, which has to be laboriously removed and processed, is not produced.

When powder is added to an open container from above, dust above the liquid on damp surfaces leads to adhesions, powder crusts and soiling on the container wall, container lid, agitator shaft and all the fixtures in the container, the removal of which is time-consuming and energy-intensive. In closed systems with a powder feed below the liquid level, however, the lid area of the container can be kept largely clean. Depending on the application, ystral also uses fogging nozzles, for example to prevent water-based paints from drying when the product is pumped out. The main liquid component is finely atomized in the container via such a nozzle, creating a humid climate above the product that reliably prevents drying. This is not possible with an open process.

ystral has also developed cleaning concepts for the system periphery with powder and liquid handling and the cleaning of pump-out lines. For example, a specially designed rinsing quiver is used to clean suction lances. This makes it possible to integrate the suction lance, which is contaminated inside and out with the raw material, into the CIP cleaning of the system when connected and thus to clean it quickly and easily.

 Process plant for a printing ink manufacturer Process plant with cleaning system for a printing ink manufacturer

Transferable experience

When it comes to cleaning processes, ystral uses experience from industries with very high hygiene requirements, such as the pharmaceutical or food industry, for applications in completely different industries. A machine used to produce paints and varnishes can be cleaned just as easily and quickly as a machine used to produce baby food. For a printing ink manufacturer, for example, ystral has installed a process system designed for colour changes, on which colour changes from black to yellow can be realized within measurable contamination limits of 100 ppm.

In paint and ink production, hygienic design systems also enable water-based products to be manufactured with a significantly lower use of biocides. The consistent avoidance of zones with little or no flow ensures that no germ nests can form.

Individual concepts

ystral solutions for the implementation of cleaning processes are always tailored to the specific system design and the respective application. For a manufacturer of fragrances whose aim is to implement cleaning processes in an energy-efficient manner and with low cleaning water consumption, for example, the company has integrated a rinsing water tank between two process systems, which is used by both systems. To clean a ystral system, the water from this tank at a temperature of around 60 °C is used for a pre-rinse step, pumped out and the system is then cleaned in a second rinse cycle with water at a temperature of 80 °C. Once the fine cleaning process is complete, this water is used to clean the system. Once fine cleaning is complete, this water is pumped into the rinse water tank, where it can be used for pre-cleaning in the next cleaning process. In this way, the user was able to significantly reduce the amount of water and energy required for cleaning.

It is also important for the fragrance manufacturer that the system can be completely dried within a short time after hot water cleaning. To do this, any remaining cleaning medium is blown out of the system using compressed air by controlling various valves. Hygienic Design makes it possible to dry a system automatically within a few minutes; only the manhole cover needs to be dried manually.

Competitive advantage

In today's process industry, flexibility is essential for survival: manufacturers must be able to produce a large number of product variants and newly developed products in an order- and user-oriented manner, i.e. to realize frequent product changes. Optimized system design and simple, fast and resource-saving cleaning can give users from sectors such as the coatings, paint and chemical industries in particular, where systems are often not yet constructed according to the rules of hygienic design, a competitive advantage.

[Translate to Englisch:] Bild des Fachartikels Effizient Reinigen

Magazine: P&A - Reshape Process Industry
Author: Denis Hunn
Publication date: 11/2023

About ystral

With our vast knowledge and many years of experience in Process- and Application Engineering we offer targeted, customer-oriented solutions across industries - from lab equipment to production machines or plants.
Together with you, we develop concepts and implementations for your individual applications, which mean mmediately realisable and quantifiable added value for you.ou.

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