Smoother than ever Effervescent powders are hygroscopic anddemonstrate poor flow properties. As such, the fillshoes and paddles of the tablet press must bedesigned to accommodate efficient filling anduniform distribution within the die. The powdercan also be lubricated with magnesium stearate toprevent the product from sticking to the tooling.An external lubricant supply system sprays thepunch tips and the die walls during the productionprocess. This has the advantage that the lubricantno longer has to be mixed into the productbeforehand. Much less material is required forexternal lubrication and harder tablets can beachieved as a result, which improves the overallquality of the end product. What’s more, externallubrication protects both the product and themachine by reducing the tablet ejection force.Effervescent tablets that are lubricated using anexternal system have a smoother surface, containless magnesium stearate and dissolve in waterwithout leaving a greasy film, much to the delightof the consumer.

Cool machinesExtremely low temperatures are essential toprocess temperature-sensitive medications. Theprocess temperature of the tablet presses inRomaco Kilian’s KTP X series is therefore kept ata constant level — below 30 °C. To reduce heatinput, the compression rollers are fitted withsmooth-running bearings and the fill shoe gear ismounted externally. A special cooling ring,situated underneath the die table, acts as athermal barrier. Additionally, the low temperaturein the service area is maintained by the torquedrive’s efficient cooling system. The brakemagnets also play a crucial role here byeliminating frictional heat and protecting thematerial. Thus, there’s no need to install an

Tableting effervescent products is a complex process. Yet, with the right technology,these tablets can be produced just as rapidly andsafely as regular oral solid dosage forms. Romaco Kilian has the perfect solution forcompressing effervescent formulations withmaximum efficiency. Children are particularly fond of effervescent

products because, quite simply, they’re fizzy. Assuch, the beverage and confectionery sectors offeran enormous variety of products … as does thepharmaceutical industry, such as pain relievers,cough syrups or medications for thegastrointestinal tract. A broad array of nutraceuticals is also available,

often in several different flavours. Theadministration of water-soluble drugs isparticularly recommended for children, the elderlyor patients with swallowing difficulties or asensitive stomach.

Tablets with complex demands Effervescent tablets offer many consumer benefits;but, manufacturing and processing thesehygroscopic products inevitably presents a numberof complicated hurdles to overcome. By their verynature, effervescent tablets react extremelyvigorously with air, light and moisture. In addition, many of the active pharmaceutical

ingredients (APIs) and vitamins processed ineffervescent formulations are readily affected byheat. Furthermore, effervescent tablets tend to befriable and susceptible to breakage. All thesefactors must be considered when tabletingeffervescent powders. The Romaco Kilian KTP590X tablet press is tailor made for these kinds ofapplications.

Gentle compression Effervescent tablets are naturally prone tounwanted air pockets and capping, which is whythe tableting process takes place in three steps.The Kilian KTP 590X single-sided rotary press isconsequently equipped with three separatecompression stations. The first compression rollersimply tamps the powder. Next, the tablets areprecompressed; in the third step, they areconverted into finished products in the maincompression unit. The use of Kilian 28/41 toolingsimultaneously extends the dwell time, meaningthat harder tablets can be made because there ismore overall time for deaeration. This stops thetablets from bursting during subsequentprocessing steps.

38 manufacturing chemist April 2018

Technologies to tablet effervescent products

More thansimply fizzy

SOLID DOSAGE

The Kilian KTP 590X single-sided rotary press is equippedwith three separatecompression stations

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April 2018 manufacturing chemist 39

precisely this reason. This prevents tablet dustfrom entering the machine compartment or, in theopposite direction, machine oil fromcontaminating the product. A patented punchbellows surrounds the upper and lower punchesand protects the tablets from impairments in theform of black spots. The closed system, made from an elastic

synthetic material, is ventilated by means of holes

additional cooling unitwhen tableting temperature-sensitive products.

Fast off the markIf effervescent tablets are to be manufacturedefficiently, it is vital to optimise the retooling andcleaning times. The number of product-contactparts in the tablet presses has been systematicallyreduced by Kilian for this very purpose.Furthermore, the die-table, tablet chute and fillshoe can be swung right out for easy access to all components. Format changes can be completed without any

additional tools. At the same time, the start-updosing control based on the filling parametersshortens the run-in times and avoids materialloss. The OEE (overall equipment effectiveness) ofthe tablet press can be significantly improvedunder these conditions. Depending on the formulation, the Kilian KTP

590X achieves an output of up to 290,000effervescent tablets an hour with mono or bilayerformats; the single-sided rotary press manages amaximum hourly output of 511,200 tablets.

Clean performanceManufacturing effervescent tablets is anextremely dusty affair. Hygienic design is all themore important to keep unwanted dust formationin check. The compaction, retooling and serviceareas of the KTP 590X are strictly separated for

The die-table, tablet chuteand fill shoe can beswung right out for easyaccess to all components

Brake magnets play a crucialrole by eliminating frictionalheat and protecting theproduct

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SOLID DOSAGE

40 manufacturing chemist April 2018

FOR MOREINFORMATIONPeter HeynTechnical MarketingRomaco Kilian GmbHwww.romaco.com

in the die table. The press’s fill shoe and tabletchute are fully washable and easy to clean. Theconcentration of particles in the productionenvironment is greatly reduced by the dust-tighttablet chute. In short, Kilian’s hygiene conceptensures reliable processing and reduces the risk ofcross-contamination to a minimum.

Safe processingOnce the effervescent tablets have beencompressed, they must be further processedaccording to the specific application. Owing totheir chemical and physical properties,effervescents are not stored in a buffer containerbut transferred directly to downstream packagingmachines. A special transfer station developed byRomaco conveys the fragile tablets from the pressto the primary packaging unit. The tablets are fed from the press scraper

directly to a high-speed Kilian conveyor belt.Tailbacks of tablets at the press discharge area areprevented by acceleration, so that the products areremoved and separated gently. This enablesselective sampling before the tablets aredistributed by a rotary table to the primarypackaging machine’s conveyor belt.On their way to this machine, they pass via two

more stations for dust aspiration and breakageelimination. Effervescent tablets are normally

packed in strips or tubes. The Romaco Sieblerbrand includes both heat-sealing machines andtube fillers. Together with Kilian presses, these twoproduct lines form a functional unit to manufactureand package effervescent tablets. Romaco’seffervescent portfolio is optimally complemented byPromatic cartoners and case packers.

Kilian’s hygieneconcept ensures

reliable processing andreduces the risk of

cross-contamination toa minimum

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