Front Cover Feature
Designing compounding plants: A bespoke solution every time This article by Karl-Heinz Bußbach, Global Business Director AZO®Poly, shows that every compounding plant must satisfy specific requirements. This is where custom designs are called for and these require plant manufacturers to have extensive, in-depth knowledge and experience of processes and raw materials and an intelligent portfolio of products.
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s a result of increasingly complex requirements, the various stages involved in compounding are gaining in importance throughout the value chain for manufacture of plastic parts. Mixing different base materials ensures that end products have a wide variety of functions and properties. The challenges involved in materials handling are equally diverse: unstable materials, combustible or abrasive components, fluctuating MFI figures within a process, a large number of raw materials, a wide variety of formulations and stringent requirements for quality and product liability, to name but a few. This is why individual concepts for plants are needed when it comes to compounding processes. These concepts should ensure a high degree of flexibility and reliability for low to high rates of output. Innovative solutions illustrated using four examples from actual practice Compounding plant for basic stabilisation of PP powder The plant in the first example involves a compounding plant for basic stabilisation. In this case, the polymer comes from six vaporisers downstream of the reactors. The particular challenges of this project include:
Compounding plant for basic stabilisation of PP powder
• fluctuations in MFI figures as a result of the batch process • ATEX gas zone outside the plant in the polymerisation section • the material still contains volatile, combustible components • an ATEX zone inside the plant, thus entailing handling in a nitrogen-atmosphere = relevant to safety • handling in a nitrogen-atmosphere due to unstable material/risk of oxidation = relevant to process • fluctuations in process parameters within the polymerisation process (batch process) necessitate the very best concept for homogenisation • high availability 24 hours a day, seven days a week, a maximum of one two shutdowns a year • conveying distances of over 300 m with relatively high throughput Implementation The following components are relevant to processes and safety when handling materials in a closed nitrogen cycle: filters, gas analysis, circulation fans,
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SEPTEMBER 2018