Another gentle-handling option is the eccentric disc pump. Craft brewer Todd Haug of the Twin Cities' Surly Brewing Co. rejected centrifugal pumps out of hand because of the pulsation that accompanies slip, and his peers discouraged the use of rotary lobes because of maintenance issues. Low shear and elimination of pulsation led to selection of the Mouvex C-series eccentric disc pump, which provides enough suction to evacuate yeast and other sediment from tanks without succumbing to cavitation. The absence of mechanical seals prevents air and subsequent oxidation from impacting the product.
Eccentric movement pumps are ill-suited for liquids exceeding 10,000 centipoise, acknowledges Wallace Wittkoff, director-global segment marketing/hygienics at Pump Solutions Group, the Oak Brook Terrace, Ill., consortium that includes Mouvex pumps. Low viscosity beverages such as beer, on the other hand, are prime candidates.
"Where product recovery is important or when you're dealing with sugary products that can crystallize on seals, eccentric discs are an ideal solution," says Wittkoff. He recalls an application in which a processor was storing a liquid sugar formulation for two days in a tank to deaerate the product. By replacing a positive displacement pump with an eccentric disc, hold time was reduced to three hours.
Shear is not an issue in direct dispersion of dry powders into a liquid stream. In fact, "the more energy you're able to put in, the faster the job is going to get done," notes Dan Osiedacz, a product manager with Fristam Pumps USA, Middleton, Wis.
But powder mixers coupled with shear blenders developed a bad rap when centrifugal pumps provided the interface between those components. Air bubbles tended to get pulled in, halting pumping action and forcing operators to physically clear powder from the base of the funnel. Ten years ago, Fristam resolved the problem by swapping in a liquid ring pump. "The pump is the key part, because the strong suction can pump any entrained air and continue to pull the powder in," Osiedacz explains.
DIY CIP chemicals
Generators that produce electrolyzed oxidative (EO) water have been the subject of both academic research and commercial development for the past decade in North America, although the technology's initial use traces to the 1990s and Japan, where the generators were used in carpet cleaning. Several start-up companies refined the technology for use in food & beverage facilities, with EAU Technologies Inc. scoring the biggest successes in commercial applications (the firm relocated from Utah to Atlanta because of Georgia's prominence in carpet manufacturing).
EO water's biggest breakthrough may have occurred three years ago when SPX Corp. licensed EAU's technology. Under the wing of SPX's flow technology segment, multiple systems have been installed at carbonated beverage facilities. They have been validated for sport drinks, flavored waters and other pumpable foods.
An EO generator contains cathode and anode electrodes separated by a dividing membrane. Sodium chloride (salt) and softened water are electrolyzed to produce hypochlorous acid and sodium hydroxide, which are polarized and separated by the membrane. The resulting sanitizer and cleaner are then used in a CIP system, eliminating the need to purchase and store chemicals on site.
Beverage processors have a bigger need for the cleaning solution than the sanitizer, notes Jeff Sporer, director of sales in SPX's Delavan, Wis., office, but the EO generator primarily produces sanitizer. Rather than send sanitizer to drain, SPX's APVSafewater system recirculates it and adds sodium carbonate (soda ash), creating additional cleaning solution.
"We produce it at full usage strength, unlike other systems that create a concentrated solution that requires dilution," says Sporer. Producing a ready-to-use cleaner eliminates the need for balancing pH, conductivity and concentration.
Carbonated beverage processors who have implemented SPX's technology report annual savings of more than $100,000 in chemical purchases alone, Sporer maintains, but an even bigger benefit is up to 50 percent reduction in CIP cycle time. "The added uptime means maybe $1 million a year to them," he says. They also are realizing water savings of 20-40% and have simplified their wastewater-treatment process.
After one facility completed its validation, "workers thanked us because of the safety factor: They no longer had to deal with chemical spills, and burns from hot pipes don't occur," Sporer says. Instead of heating CIP water to 180°F, the plant dialed it down to 100°, thereby saving energy.
Fluid dairy operations and copackers who daily execute multiple CIP cycles are prime candidates for the technology. "The biggest payback is in applications where there are a high number of CIPs," he adds. "This is really a game changing solution for a lot of processors."
Dairy processors understandably are averse to the risk inherent in change, and none has been willing to undergo the validation needed to apply EO water to their operations. The same cannot be said of UV sterilization of packaging materials: Dairy is at the forefront of adoption of pulsed UV systems from Claranor. About 90 systems are in commercial use.
Elimination of chemical purchases contributes to the cost justification of pulsed UV, although the greater savings come from water: The purchase, heating and disposal costs of water-based sterilization fluids using peracetic acid or peroxide are non-existent. Overall operating costs are calculated to be as much as 70 percent less than with conventional cap-sterilization methods.
Half of Claranor's installations are in dairies, including two U.S. processors who are engaged in the validation stage. "Pulsed light is efficient on dry, smooth surfaces, with high efficiency on very resistant germs and with very low energy consumption," states Christophe Riedel, managing director at Claranor, Avignon, France, in an email. "A Claranor cap treatment providing 3 log reduction operates at 720 bpm with only 1 kW power."
Claranor's experiences illustrate the many ways process improvements can be derailed. Last year, the firm partnered with Fowler Products, an OEM of bottle capping systems, for North American distribution. Unfortunately, Fowler's strong suit is in the liquor segment, while Claranor is appealing to dairies, so the partnership was dissolved.
Business issues can derail promising technologies, but as Hormel's micro-encapsulation illustrates, process refinements and persistence can overcome them.