Building chemistry

The Solution

Automated bulk materials handling in the manufacture of tile adhesives and plasters

• In the plant in the illustration, 50 different raw materials are automatically stored, transferred, dosed, weighed and made available to the mixing process. The batches are filled into a very diverse containers after mixing. 50 different formulations with up to 20 components are documented in the manufacturing process, produced in consistent quality and managed using the process control and instrumentation system.
• There are 15 silos for storing bulk components. Depending on their flow properties, these are fed using vacuum conveying and various discharge aids to four scale hoppers, which are installed above the mixer lines. A combination of large-dimensioned conveying screws and small dosing screws, which ensure fine metering into the scale hoppers, are used to convey and dose the components.
• One of the mixer lines serves to produce premixes that can be filled into AZO DOSITAINERS® or big bags. These premixes are supplied to the next mixing process that is carried out on the other mixer lines.
• Medium components and minor components are supplied in big bags or sacks. Depending on the quantity in the formulations, the raw materials are either transferred into day bins or AZO DOSITAINERS® or supplied directly above the AZO COMPONENTER®.
• The AZO COMPONENTER®, AZO’s flexible container system, is responsible for assembling almost all medium and minor components. Maximum accuracy is required here while providing the greatest possible flexibility for changing formulations over. Changing components are thus supplied in AZO DOSITAINERS®, which make it simple to switch products while keeping the need for cleaning to a minimum. Dosing screws help to achieve the different degrees of accuracy required in dosing and weighing, as does the use of the AZODOS gravimetric dosing units, which operate as loss-in-weight scales.
• The AZO COMPONENTER® works with two separate drive units including platform scales. The bulk materials containers mounted on the scales are filled in parallel. This increases the throughput rate of the plant and reduces idle times.
• Once batch formulation for medium and minor quantities is complete, the bulk materials container with the AZO COMPONENTER® is conveyed onto the mixer lines and fed to the mixers.
• Some components can also be discharged directly into the mixer. There are two discharge stations above the mixer for this. Direct feeding of the components is monitored and approved by means of bar code identification.
• The entire production process from storage of raw materials through to feeding of the mixers is documented in batch protocols.
• The Kastor process control and instrumentation system with formulation management ensures that production is both reliable and efficient and that the plant and the mixer lines are used to maximum capacity.
• The flexibility required for the plant is also reflected where filling after the mixing lines is concerned. Thanks to the plant’s modular design, filling is possible into bulk materials containers and into big bags and sacks.