MechChem Africa June 2019

Integrated Pump Technology’s Scott Gordon talks to MechChemAfrica about the Leybold Vacuum product line and the advantages of two recent additions: the Leybold NovaDry vacuum pump for food processing and packaging; and ScrollVac, a low power state-of-the art vacuum system for demanding applications. Dry vacuum pumps for better food processing

S cott Gordon has a long history in South Africa’s vacuum pump in- dustry, having spent over 27 years working for a local manufacturer of liquid ring vacuum pumps. “Integrated Pump Rental, however, is a local agent for Leybold Vacuum, which has taken the stra- tegic decision to focus on dry-type vacuum systems, so liquid ring vacuum systems are not included in the Leybold range,” Gordon tells MechChem Africa . Vacuum applications can be slotted into four categories: rough, medium, high and ultra-high vacuum. “Rough vacuum is con- sidered to be anywhere below atmospheric pressure and above 1.0 mbar; medium vac- uum sits between 1.0 mbar to 0.001 mbar; high vacuum takes the pressure down to 0.0000001 mbar and ultra-high vacuum can go well below that,” explains Gordon, adding that high and ultra-high vacuum can gener- ally only be generated using combinations of technologies, such as a sliding vane pump connected to a roots pump and then to a dif- fusion pump, for example. Cryogenic systems and coldheads andother equipmentmay also be applied. Cologne-basedLeyboldVacuum,apioneer of vacuum systems for nearly 170 years, has vacuum equipment to meet all four of these vacuum levels. The company offers 13 main

rotary vane pumps to ultra-high vacuum diffusion and cryogenic pump technologies. Why the focus on dry systems? “Dry vacuumtechnologies tend tobeable tohandle a wider range of gases, for example SO 2 from anacidplant. If usingaswet system, suchas an oil-flooded sliding vanepump, acidic fume can mix with the oil and break it down. Such con- tamination is not an issue if usingadry system. BrandnewtoLeybold’s product range is its dry screw-type vacuum pump, the NovaDry, which was launched in May at the interna- tional trade fair for the meat industry (IFFA) in Frankfurt. This newly developed, oil-free screw vacuum pump ensures significantly greater safetyandefficiency in foodandpack- aging processes. “With five sizes available to deliver from 65 m 3 /h to 200 m 3 /h evacuation rates and absolute vacuum pressures down to 0.1 mbar, these pumps fit into the medium vacuum category and are designed to meet FDA requirements without the need for ad- ditional filtration,” says Gordon. “Leybold’sNovaDrypumpsoffertheshort- est pump-down times in the industry, which means they can evacuate enclosed spaces faster than any similarly specified pump on the market. In addition: • They have a compact design, whichmakes themeasytoincorporateintofoodpackag- ing machines and modular systems. • Noise levels have been reduced for amore comfortable working environment. • The air is 100% oil free, which leads to a

more sanitary environment required for food related applications. “Oil flooded vacuum pumps produce an oil mist in the discharge stream, whichwould have to be taken out by filters before being allowed to enter the atmosphere. The Nova Dry pumps do not contaminate the air in any way, so they do not require such systems,” Gordon explains. • The pumps can alsohandle lowconcentra- tions of food particles in the air such as marinade and sauces, which would con- taminate the oil used in non-dry systems. • These systems are air-cooled, so they require no additional cooling water. “This 100%oil-free vacuumpump is a first for the food industry and is set to revolutionise themarket. Oil-sealed rotary vane pumps are the norm, but they pose contamination risks. The NovaDry avoids these risks and ensures food quality and freshness is maintained,” Gordon notes, adding that this pump is set to become an industry benchmark. Globally, Leyold’s NovaDry oil-free vacu- umpumps are replacing the company’s legacy range of oil-flooded Sogevac sliding vane pumps, which remainavailable and supported in South Africa through Integrated Pump Technology. Also recently added to the local offering is the new Leybold ScrollVac pump. “These systems use two mating scrolls rotating against each other to create compressed air pockets that create the vacuum. All vacuum equipment works by compressing the gas, whichcreateslowpressurevoidsdownstream of the compression point. If the downstream space is isolated from the atmosphere, then the pressure in the space reduces continu- ously asmore andmore air is compressed and evacuated,” Gordon explains. “These machines require very high preci- sion machining to minimise slippage, which is the industry term for the amount of gas that bypasses the internal components of a vacuum pump. Slippage limits the degree of vacuum possible from a particular pump technology. The better design of the ScrollVac’s tip seals leads to much less slip and, therefore, better vacuum retention on the high end of

categories of vacuum prod- ucts to achieve this: from relatively simple oil-sealed

The new Leybold NovaDry dry screw-type vacuum pump can evacuate enclosed spaces faster than any similarly specified pump on the market.

10 ¦ MechChem Africa • June 2019