When processing up to 500 jars a minute of jams, preserves and other products, the last thing maintenance needs to worry about is the process water of the spray pasteurizer.
But, that is the only thing a dedicated maintenance worker was assigned to do: Monitor the filtration system. In-line carbon steel filters, designed to filter particles on a pasteurizer-cooler line, were pitting and creating a maintenance and operation nightmare at the Knott’s Berry Farm Foods plant in Placentia, Calif. The plant produces everything from its famous jams, jellies and preserves to salad dressings, syrups, bakery fillings and yogurt bases. “All our products come out of this one 250,000-sq.-ft. facility,” says Tom McMahon, maintenance supervisor. “We run production 171/2 hours a clay. The last thing we could afford is to shut down the pasteurizer because the filter would lose integrity and allow particles such as fruit seeds to pass through and clog some of the 200 nozzles spraying 210°F water on the jars.”
As with any filling and capping system, a container periodically gets overfilled or a lid is misapplied. When this container enters the tunnel pasteurizer and heats up to 180°F or more, the lid may pop off and spill product (usually acidic preserves or jams) into the pump system,” explains McMahon. Not only did this cause product to enter the filter but the products’ acidic nature was pitting the carbon steel filter, requiring constant maintenance.
“We were manually cleaning the system four to five times per day,” adds Louie Delgadillo, maintenance mechanic on the line. “Each delay caused about 20 minutes of downtime. At up to 500 containers a minute, it really added up fast.” The company turned to Automatic Filters for a solution to this blatant problem.
In January, Knott’s Berry Farm Foods installed a stainless steel Tekleen® filter system with a 400-micron mesh screen from Automatic Filters Inc. The filter is a two-stage design with an automatic back-flushing system. triggered by a preset pressure differential between the in-flow and out-flow pressures.
Process water enters through a coarse screen into the interior of the filter. The flow then transfers to the second stage where it passes through the fine mesh screen to the filter’s perimeter and is discharged. As water flows through the fine filter, there is a gradual buildup of seeds and other fine particulates on the. mesh screen. This debris causes an increase in pressure differential between the inlet and the outlet of the filter.
“When the pressure difference reaches seven psi — a setting we determined based on number of cycles and amount of debris — it triggers the back-Rush valve and the cleaning cycle begins,” says McMahon.
A vacuum rotor with several suction nozzles, suspended within the filter, connects to a pipe that traverses to a separate discharge chamber. As the flushing valve opens, it creates a suction in the discharge pipe causing the nozzles to rotate as they stick in trapped debris. “The whole process takes only 2-3 seconds per cycle and leaves a. clean filter surface,” adds McMahon.
The all-stainless steel Tekleen is rated to 210°F and-handles up to 250 gpm. It also has a high performance screen sintered to perforated metal, yielding about 80% more filter area than other filters sintered to PVC. “To top it off, the Tekleen’s price is almost $1,000 less than a carbon steel filter. What other justification does anyone need?” says McMahon. “The choice was obvious.”
Cool, clear water is the life force in manufacturing operations. It cools, cleans, and can be counted on to run pure and steady — unless it becomes contaminated with dirt and other pollutants. Then, it can gum up a system, impede operations, and even impair the quality of the products being made.
Water filtration is one of the most effective and least expensive ways to solve equipment fouling and scaling problems caused by dirty water. Heat exchangers, molds, pipes, tubing, sensors, monitors, and other parts become fouled when dirt particles in the water settle out on warm surfaces. Calcium and magnesium are the bonding elements that cement the dirt onto the equipment. Chemical analysis shows that the calcium and magnesium are less than 2 percent of the fouling material – – the rest is made up of airborne particles, rust, sand, biological organisms, and other contaminants. Scale formation reduces the heat transfer rate and increase the water pressure drop through the heat exchanger and pipes. In fact, one study from the Carrier Corp., Syracuse, N.Y., has shown that 0.002” fouling will increase pumping needs by 20 percent.
Not all water filtration systems are alike. Carbon and sand filters require regular maintenance that can result in downtime and higher labor costs. A continuous-cleaning filter that requires no maintenance might be an alternative for your processing plant. As dirt particles collect on the screen the line pressure at the filter outlet drops. When the pressure reaches a preset differential, the backwash cycle begins. Within seconds and without interrupting the main flow, vacuum nozzles aggressively suction the dirt from the inside of the screen. This inline full-flow automatic filter is one solution for cleaning dirty water and preventing unscheduled shutdowns for maintenance and cleaning.
This automatic, self-cleaning filter is suitable for a range of applications. Bruce foods, New Iberia, La. plantmanufactures Cajun and Tex-Mex foods from four locations within the United States. The company’s Wilson, N.C. plant manufactures canned yams. During the canning process, the yams must be sterilized to 240°F (166°C) and then cooled to 105°F (41°C) using water that is pumped through the system at a rate of 800 to 1,000 gal/min. As part of Bruce Foods’ water conservation program, the cooling water is recycled. Without filtration, the water would pick up dirt, dust, and other impurities that could stain the exterior of the container. To solve this problem, the plant installed an automatic, self-cleaning water filter with a 100 µm screen, a size that is adequate to filter out the impurities without causing an excessive amount of backwashing.
No matter what type of processing application you have, automatic, selfcleaning water filters might be the way to help reduce downtime and labor by eliminating the need to clean and replace cartridges, bags, screens, and spray nozzles. Rinsing lasts a few seconds and can use as little as two gallons of water, all without interrupting the main flow, to help increase your bottom line.