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 increases 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.
Production had to be stopped every other week for several hours to clean the lines. "One time, I lost a condenser when it got clogged with dirt, became impacted with ice and broke off," says Alfredo Romero, maintenance manager at Rehrig Pacific's Los Angeles plant. The downtime caused by frequent cleanings was taking a toll on the company's productivity.
Rehrig Pacific had one 4" automatic water filter installed in the tower. Results were positive, and the company purchased five more filters for the Los Angeles plant as well as additional filters for its plants in Georgia, Kansas and Texas. Romero says he no longer has to worry about dirty water clogging the lines, destroying valuable equipment and interrupting the production process.
"We were using cartridge filters that were not providing adequate filtration," says project manager Bob Morrow. "We needed to be able to filter all the water going to the process, not just the sidestream water." For Fiberlux, water serves as both a cooling medium and the sealing agent in vacuum pumps. When the water picks up contaminants from the air, it causes frequent clogging and creates drag. This affects the quality of the finished product and forces production stoppages for cleaning.
Fiberlux solved the problem by installing two automatic, self-cleaning water filters. Morrow says that since the installation, the company's water clarity has improved. "Having 100 percent filtration of all the water going to the equipment has improved the quality of the finished product, and our processing problems related to contaminants in the water have gone away," Morrow says.
No matter what type of processing application you have, automatic, self-cleaning 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.