If you have eaten something sweet today, chances are you consumed corn syrup. So, what is corn syrup? Corn syrup is used in foods to soften texture, add volume, prevent crystallization of sugar and enhance flavor. High-fructose corn syrup is manufactured from corn syrup by converting a large proportion of its glucose into fructose, producing an even sweeter compound.

One of the world’s leading producers of corn sweeteners, including corn syrups, high-fructose corn syrups, maltodextrin, crystalline fructose and dextrose wanted to improve its production process to reduce product loss, decrease maintenance costs and minimize injury risks. Specifically, the company evaluated its existing filtration system and sought an improved solution that included a less labor-intensive filter- cleaning process.

Challenge to corn syrup manufacturing

Corn syrup manufacturing is a multi-step process with unique challenges at each stage. After the incoming corn is inspected and cleaned, it is steeped for 30 to 40 hours to begin breaking the starch and protein bonds. The third step in the process involves coarsely grinding the corn to separate the germ from the rest of the kernel. The remaining slurry, consisting of fiber, starch and protein, is finely ground and filtered to separate the fiber from the starch and protein.

The starch is then separated from the remaining slurry in hydrocyclones, which isolates particles in a liquid suspension. Finally, the starch can be converted to syrup. The company approached Eaton for help with the filtration system used in the syrup
conversion process.

Read Also: Solid-liquid filtration basics for process engineers

The Eaton tubular filters installed in the 1970s were dependable but due for an upgrade.

The corn syrup producer’s manager and process engineer met with the manufacturer to discuss the current filters and plans to upgrade the process. They wanted to implement the latest technologies to improve their process, reduce labor, improve safety and eliminate frequent cleaning.

Addressing potential safety hazards was of utmost importance while implementing the new process. During processing, thick fluids are often heated to increase the speed and efficiency with which they move through the process. The materials running through the tubular filters often reached temperatures of up to 140˚C and posed a burn hazard to equipment operators if leakage occurred through gaskets or other connection points. Frequent maintenance and filter cleaning added risk by increasing exposure to the hot fluids.

Another factor considered when identifying the right filtration solution was the required flow rate of up to 2,500 gallons per minute (gpm). With 150,000 gallons of hot, sticky fluid moving through the process every hour, this factor created a need to increase the system’s capacity.

Figure 1. This mechanically cleaned filter unit moves incoming fluids from the interior cylinder (1) through a wire screen (2) to the outer cylinder and out the discharge port (3). A magnetically coupled cleaning disc (4) travels down and up inside the cylinder to periodically clear the filter screen. Particles are collected at the bottom of the housing where they can be discharged (5).

Figure 1. This mechanically cleaned filter unit moves incoming fluids from the interior cylinder (1) through a wire screen (2) to the outer cylinder and out the discharge port (3). A magnetically coupled cleaning disc (4) travels down and up inside the cylinder to periodically clear the filter screen. Particles are collected at the bottom of the housing where they can be discharged (5).

Maintenance costs were an additional sticking point for the customer. With the existing system, filters needed to be cleaned three times per week by an outside maintenance crew. If an unexpected issue arose, these cleanings were even more frequent, resulting in more downtime and expense. Frequent filter maintenance also increased the loss of valuable product and potential loss of an entire batch of corn syrup.

Solution

A mechanically coupled, high-flow strainer was recommended for the job. This technology provides quick and easy access for maintenance, reduces potential leaks, and requires fewer moving parts. Other benefits include:

  • Minimal purge for low-waste operation
  • Easy inline installation
  • Continuous 24/7 operation
  • Maintenance-friendly design resulting in lower labor costs
  • Eco-friendly with no bags to purchase, change or landfill
  • Available in optional American Society of Mechanical Engineers code

This mechanically cleaned filter unit (see Figure 1) moves incoming fluids from the interior cylinder through a wire screen to the outer cylinder and out the discharge port. A magnetically coupled cleaning disc travels down and up inside the cylinder to periodically clear the filter screen. Particles are collected at the bottom of the housing where they can be discharged.

Results

The customer proceeded with the installation of the MCS-500 (see Image 1) mechanically coupled strainer on a trial basis to gather data and measure success. After several months, the overall results exceeded expectations.

The multiplex system design featured a multistation configuration that allowed for the flexibility of additional capacity in the future if required. The customer opted to purchase five filters to start with the capability of adding a sixth in the future.

Since this strainer has been in operation, the filtration process has become more stable, resulting in less product loss, limited maintenance intervention, and decreased labor and maintenance costs. Other areas of the plant noticed the positive outcome and expressed interest in learning how the solution could meet similar needs in their applications.

Those are pretty sweet results.

Margaret DeAngelis is the global marketing communications manager – Hydraulics Group – Filtration Division of Eaton, a $20.9 billion global power management company. DeAngelis leads a global team building the online presence and media relationships for the Filtration Division. Since joining Eaton in 2009, DeAngelis has helped the Filtration Division grow as a leader in the liquid filtration market.