Process Units for Solids - SOLIDMIX

By definition, an appliance alone cannot be described as sustainable. However, an apparatus solution that helps to optimize your manufacturing process makes your process demonstrably more “sustainable”. Long before the label “sustainability” existed, EKATO was already dedicated to optimizing processes through optimum agitator technology:

• Minimization of energy contributions in the process. (energy balance)
• Reduction in the use of raw materials through better process engineering.
• Simplification of equipment solutions through the use of one-pot systems

When optimizing your process, we can draw on experience from the above-mentioned industries – and look beyond the edge of the plate.

Your process developed through the use of EKATO technology and experience proudly deserves the label “sustainable”.

For free-flowing solids or large apparatus volumes, the SOLIDS-PARAVISC impeller is used in the SOLIDMIX VST series. The ISOPAS impeller was designed for processing pasty, high viscous media, or for applications where the discharge behavior of the products requires an agitator system with minimal wetted surfaces.

A conical vacuum contact dryer is extensively used in the pharmaceutical, chemical, and food industries for its highly efficient drying capabilities and versatility. Key processes within this dryer include mixing, drying, and solvent recovery. The conical shape is designed to promote uniform mixing and drying by ensuring thorough contact between the product and the heated surfaces.

The application of vacuum reduces the boiling point of solvents, allowing for gentle drying at lower temperatures. This is especially advantageous for heat-sensitive materials, preserving their quality and integrity. The rotating motion of the dryer further enhances mixing, ensuring even heat distribution and preventing agglomeration of the product.

1…2: Liquid due to extractions or chemical reactions ~ 90% solvents
3…4: Pasty filter cakes ~ 50% solvents
3…5:  Moist material from centrifuges, nutche, decanter ~ 40% solvents
6: Spray dried powder for post drying ~ 8% solvents

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience
• Practical solutions developed by experts from the field and basic researchers
• EKATO is your partner throughout the entire lifecycle of your application

From an energy point of view, mechanical dewatering methods should always
be used before vacuum contact drying.
However, there are products for which mechanical dewatering is not possible. Vacuum contact drying can close the gap here. Dryers work effectively if a minimum filling level is guaranteed.

The versatile agitator technology in the EKATO SOLIDMIX dryer allows the evaporation of slurries with a low solids content with the aim of concentration. Once the mass has been concentrated by adding slurry during the condense process, efficient drying can be started. The concept works with a continuous supply of slurry – the “fed-batch process”.

Typical applications: aroma extraction from leaves with a low solids content in the solution.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience
• The one-vessel process reduces the amount of equipment required and cuts installation costs
• EKATO is your partner throughout the entire lifecycle of your application

Spraying a liquid onto a mixed solids bed in a single-pot operation is a crucial technique in various industries, including pharmaceuticals, catalyst production,
and food processing. This process involves uniformly distributing a liquid onto a bed of mixed solids within a single vessel, enhancing efficiency and consistency. The liquid, often a precious metal solution, a binder, coating, or reactant, is sprayed through nozzles or atomizers, ensuring even coverage. The single-pot operation minimizes handling and transfer steps, reducing contamination risks and improving product uniformity. This method is advantageous for processes requiring precise control over the liquid-to-solid ratio, such as coating, or wet massing. Designed as a solid agitator, the EKATO ISOPAS is particularly suitable for spraying processes. The open shape – without bars in the product chamber – allows spraying even with changing fill levels.

Typical applications for impregnation and spraying are:

• Automotive catalysts
• Decorative sugars
• Coatings for bulk materials

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• Dust-free processes are possible with EKATO technology. The advantage for the operator and the environment
• EKATO is your partner throughout the entire lifecycle of your application.

A liquid mixer (EKATO HWL) and a mixer for solids (EKATO SOLIDMIX) serve different purposes in processing industries.

Liquid mixers are designed to blend fluids, ensuring uniformity through impellers that create a turbulent flow. These mixers are effective in preventing stratification and ensuring homogeneity in liquid substances. On the other hand, mixers for solids, such as EKATO SOLIDMIX, have close-to-the-wall impellers that prevent material buildup on the vessel walls. Additionally, these mixers pump solids upwards, ensuring thorough mixing by continuously cycling the material. This design is crucial for achieving consistent mixing of solids, preventing clumping, and ensuring even distribution of components throughout the mixture.

Vessel heating is essential in many industrial processes, with various methods ensuring efficient and uniform temperature control. Three common techniques include double jackets, dimple jackets, and half-pipe coils. EKATO SOLIDMIX dryers and reactors, great importance is attached to heating or cooling that is adapted to the process. In theory and in practice. The transfer of heat and cold via the vessel wall into an agitated solid bulk material requires optimum conditions and is limited by the internal heat transfer. The circulation of a heat transfer fluid has proven itself in solid applications.

EKATO SOLIDMIX reactors and dryers for solids complete the portfolio of EKATO stirring and mixing technology for liquids. You benefit from the process know-how of the market leader. From reactors for specialty polymers (SSP at 330°C) to large systems for coffee decaffeination or cocoa alkylation (up to 32 m³), EKATO is the contact partner for your reaction applications.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience
• Benefit from the process knowledge of the EAKTO Group – transferred to your solids material application
• EKATO is your partner throughout the entire lifecycle of your application

A conventional mixer can certainly process pastes with a high solids content, but this usually takes a lot of time.
The stirring energy used often leads to undesirable heating of the product.

With the EKATO VPT and the EKATO ISOPAS agitator, an agitation system is available which can produce these mixtures in a short time and without significant heating. The agitator circulates the vessel contents with low shear but high circulation rate. This has proven itself in kneading processes. It results in a gentle sliding movement in the paste, with a positive effect on the product quality, which could only be achieved in a Z-kneader.

For process development, EKATO laboratory mixers with a capacity of 25 liters or 50 liters are available. Operating systems with a usable volume of up to 6300 liters can be designed.

If a solid that is difficult to wet is to be mixed and kneaded into a mass, a special con

cept is available. The solid (e.g. graphite or soot) is sucked into the mixing vessel “sub surface”. The liquid is simultaneously sprayed off “from the top” while the ISOPAS agitator ensures efficient mixing.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• EKATO mixers can improve product quality. Test your materials on an EKATO mixer
• EKATO mixers result in short mixing times and reduce your operating costs

Together with extrusion, spray drying is the method of choice for drying active pharmaceutical ingredients on a polymer carrier.For some product groups, however, the residual moisture content that can be achieved with reasonable effort is still too high.  With the EKATO SOLIDMIX post-drying system for spray dryers, residual moisture levels in the ppm range can be achieved.

The spray-dried polymer is fed into the EKATO dryer via containment systems, where it is dried in a deep vacuum while precisely adhering to the temperature limits. For particularly lengthy drying processes, additional measures are available to speed up the drying process: Trailing gas addition.

The evaporated solvents are collected as recyclable material. The processes can be developed and tested on a 3 liter, 25 liter and 50 liter scale. EKATO has a laboratory for this purpose. When scaling up to operating scale, great importance is also attached to a constant particle size distribution and the influence of the agitation on the bulk density – important factors for subsequent tableting.

In addition to the drying success, the maximum product output – yield – plays another important role. The EKATO SOLIDMIX VPT dryer is already characterized by an optimized agitator design. Additional measures are available for post-drying, e.g. the EKATO Yield Blade. Laboratory tests can also be carried out here.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• EKATO mixers can improve product quality. Test your materials on an EKATO mixer
• EKATO mixers result in short mixing times and reduce your operating costs

Filling by gravity

EKATO supplies a technically tight device. Filling takes place from above by gravity. The apparatus is fitted with a suitable shut-off valve at the product inlet. A suitable feeding device can be attached to this interface. (BIG Bag stations, pneumatic conveying, augers).

The agitator should rotate during filling to ensure even product distribution. If the product is to be dried in parallel to filling, it can be filled via a double flap system or a rotary valve.

Discharge by gravity

EKATO supplies a technically tight device. A suitable discharge fitting is attached to the discharge opening. The agitator must be operated during discharge to prevent bridging. The agitator speed influences the discharge speed. The nominal width of the discharge must be adapted to the flow behavior of the product.

A whole series of downstream functions (sieving, filling, pneumatic conveying) can be arranged below the discharge conveyor.

The size of the outlet opening must be adapted to the flowability of the product. Bridging in the outlet is prevented by the agitator geometry.

Heating / Cooling

Vessel heating or cooling is essential in many industrial processes, with various methods ensuring efficient and uniform temperature control. Three common techniques include double jackets, dimple jackets, and half-pipe coils. EKATO SOLIDMIX dryers and reactors, great importance is attached to heating or cooling that is adapted to the process. In theory and in practice. The transfer of heat and cold via the vessel wall into an agitated solid bulk material requires optimum conditions and is limited by the internal heat transfer. The circulation of a heat transfer fluid has proven itself in solid applications.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• EKATO assumes responsibility for the process-relevant components itself
• EKATO is flexible and can take your proven suppliers into account

Evaporation and Condensation = Solvent recovery

Solvent recovery is a critical process. Evaporated solvents are condensed and collected, allowing for their reuse and making the process environmentally friendly and cost-effective. This capability not only conserves resources but also reduces operational costs. Overall, a conical vacuum contact dryer provides efficient drying, maintains high product quality, and delivers significant energy savings, making it a preferred choice in various industries.

A EKATO SOLIDMIX solvent recovery system includes components such as a pre-condenser, post-condenser, and a vacuum pump. The pre-condenser is positioned before the vacuum pump to cool and condense a large portion of the solvent vapors, reducing the load on the vacuum pump and enhancing overall efficiency. The post-condenser, located after the vacuum pump, captures any remaining solvent vapors, ensuring maximum recovery and preventing emissions. This two-stage condensation approach significantly improves solvent recovery rates. The vacuum pump is crucial for creating the necessary vacuum conditions without contaminating the solvents with oil or other lubricants, maintaining the purity and quality of the recovered solvents. Overall, these systems are vital for optimizing solvent usage, reducing operational costs, and adhering to stringent environmental regulations. EKATO SOLIDMIX designs and builds both the dryers and the solvent recovery systems. Both systems are therefore optimally matched to each other.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• EKATO assumes responsibility for the process-relevant components itself
• EKATO is flexible and can take your proven suppliers into account

Separation – Dust filter systems

EKATO builds the systems “technically tight”.  This makes it necessary to enable ventilation during filling and emptying. Whether a pendulum line or breathing filter – EKATO has the right solution in its range.

Any pressure equalization can lead to the entry of foreign bodies into the process chamber (microbes, micro dust). Product dust can enter the vent line during depressurization. The use of HEPA filters has proven its worth here.

High vapor flows occur during vacuum drying. Here it is important to separate the vapors from the entrained dust and leave the dust in the container. This must not result in significant pressure losses. The EKATO dust filter systems are specially designed for use in dryers. Many years of operating experience confirm the concept in practice.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• EKATO assumes responsibility for the process-relevant components itself
• EKATO is flexible and can take your proven suppliers into account

The EKATO SOLIDMIX dryers and reactors can be supplemented with additional functions:

Chopper:
Both the EKATO PARAVISC and the EKATO ISOPAS are regarded as gentle mixing systems. If high shear forces are required in the process (e.g. for granulation processes or to avoid lump formation), the EKATO chopper can be used.  A remote agitator installed from above, equipped with a knife mechanism, introduces controlled shearing into the solid’s mixture. The shearing effect can be controlled by a frequency converter.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• EKATO assumes responsibility for the process-relevant components itself.
• With the EKATO modular system, extensions are possible even years after commissioning

Yield Blade
The container shape of the SOLIDMIX dryers and reactors – upright with a conical bottom – is already designed for high discharge rates. However, heavy-flowing (dry) solids often adhere to the vessel surfaces or agitator elements. The EKATO Yield blade is a non-contact dedusting technology. A targeted nitrogen pulse loosens the build-up layers and supports the outflow.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• EKATO assumes responsibility for the process-relevant components itself.
• With the EKATO modular system, extensions are possible even years after commissioning

Nitrogen purge/sweep
If vacuum drying is diffusion-driven, this results in very long drying times. The addition of a defined flow of an inert gas led to a change in the partial pressure around the solid grain – this accelerates the diffusion process. EKATO has the pilot plant facilities with which this effect can be demonstrated. With the data obtained, it is then possible to design a flushing system for the plant size – also as a retrofit for existing dryers.

Your EKATO SOLIDMIX benefits:

• Reliability for your process all the way from small-scale trials to operating systems thanks to years of experience.
• EKATO assumes responsibility for the process-relevant components itself.
• With the EKATO modular system, extensions are possible even years after commissioning

All EKATO SOLIDMIX drying, and reactor systems are delivered fully automated and commissioned by us. As a result, the responsibility for process success and mechanical integrity remains in one hand.

Process benefits:

• Recording, visualization & trending
• Dynamic information system (P&ID)
• Alarm list with analytical functions
• Calibration tool
• Maintenance information
• Network data transfer
• Fully automated production possible

Data management benefits:

• User management
• Electronical Signature
• Batch Report
• Audit trail
• Data integrity – tamper proof
• Continuous traceability
• Online documentation

Regulations (standards met):

• GAMP 5 and FDA CFR Part 11
• Programming standard acc. ISA-88
• Recipe system in relation to ISPE GAMP5
• Ready to connect interfaces: OPCUA / SAP / SQL

Although EKATO has many years of experience in the design and extrapolation of solids processes, we can offer you an application laboratory for testing purposes. Here we can prove the suitability of your system on a scale between 3 liters and 100 liters and support you in the development of your new processes. Mobile systems are available for hire for on-site trials.