MATERIALS HANDLING
ABOVE: The need to use high-purity chemicals in the manufacture of numerous high-value products is a fact of life. Using Almatec plastic solid-body E-Series AODD pumps will help ensure that these liquids are fully contained and protected from contamination
chemicals. Tese products are used in precise manufacturing processes where there can be no variance in the makeup of the chemical or slippage in its overall quality. On top of the need for pristine purity is the fact that these chemicals are very expensive to produce. Terefore, if a batch is deemed not to meet expected quality levels, it can cost hundreds of thousands of dollars in lost revenue for the manufacturer – as well as putting a blemish on the manufacturer’s reputation. Additionally, because of the high stakes that are involved in the production of high- value commodities, their manufacturers will strictly audit the production processes of the chemical companies to make sure that the chemical is produced according to
established specs. Anything that can cause the chemical to become out-of-spec would be grounds for the end user to consider finding another supplier. Another concern for chemical manufacturers is that many of their products can be highly toxic and dangerous to handle. Tis means that any time high- purity chemicals are handled there is an inherent risk involved. Te risk stems from the fact that the release of these chemicals can lead to severe health consequences for humans and animals, as well as damage to the environment. With all that said, keeping dangerous high-purity chemicals fully contained is often easier said than done. Since many can also be highly corrosive, the pumping equipment used to transfer them is prone to chemical attack if the materials of construction are not compatible with the acid, caustic or solvent. Materials of construction are not the only factor to consider when determining if a pump should be used to handle dangerous chemicals. Another area to focus on is the actual design features of the pump. For example, if the design incorporates mechanical seals or packing, they may be prone to leaking. Attempts have been made to eliminate the shortcomings of pumps that feature mechanical seals through the implementation of magnetic couplings or
double barrier seals. While these methods of containment do outperform mechanical seals, they do possess some disadvantages that reduce their effectiveness. Te viscosity range of liquids that are transferred by pumps with magnetic couplings is limited by the amount of transferable torque that can be created. Te use of pumps with double seals or barrier liquids can be impractical due to their high cost and the elevated level of maintenance required. Some common pump styles that have traditionally been used to handle high- purity chemicals include lobe, gear and centrifugal models. While they may be constructed of chemically compatible materials, their design features mechanical seals, the performance of which can be compromised over time, raising the possibility that leaks will occur. In terms of actual performance, these competitive pump styles also have limits when it comes to the reliable, energy- efficient transfer of high-purity chemicals. Gear pumps, for instance, move liquids through the meshing of gears. Over time as the gears wear, the pump’s volumetric consistency is reduced, resulting in fluctuating flow rates and increased energy usage. Te operation of both gear and centrifugal pumps can also create turbulence in the pumped liquid, which can lead to shearing that will damage or alter the liquid’s chemical properties and
The plastic solid-body construction of pumps eliminates the small crevices or cavities that can be found in injection-moulded models. It is in these crevices that liquids can accumulate and leak paths can be created
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