A process engineer at a food manufacturing facility, where we had successfully completed a project two years prior, reached out to Omni with a process piping problem. Heating of the process line had not been specified on the original project, and now the client was encountering problems with liquid fat solidifying in the piping. The 140°F fat leaving a 6,000 gal. collection tank needed to stay above 130°F as it was being pumped 450 ft. to the building’s exterior to maintain its liquid state.
Working with a trusted process vendor we’ve partnered with in the past, we designed a heat-tracing system that would sustain a line temperature of 150°F over the entire length. This included specifying the type of heat trace and methods of control, monitoring, alarms, installation, and commissioning.
Considering the wattage per square foot and power requirements, two 277V circuits were selected. Each heat trace circuit was controlled with a 24V on/off controller equipped with temperature-sensing bulbs for the associated piping. Also included were a general alarm and current transmitter to monitor each line and verify proper function.
Installation of the heat trace system was precisely executed in accordance with manufacturer guidelines. In addition to the piping, there were numerous associated specialties that required heat tracing, including manual and control valves, flow meters, pumps, drainage tees, and an air valve.
During the startup phase, preliminary testing was conducted with empty piping to verify the system was delivering heat, test the temperature sensors, and determine the amperage draw on each circuit.
For the next test, the heat trace was activated by an automation engineer following a specific safety and process protocol fifteen minutes before testing was to begin. Water reading at 140°F was then pumped through the line to verify the proper operation of the pump flow meter and control valves. The heat trace successfully maintained the water temperature through the interior and exterior piping to the discharge point 450 feet away.
Finally, system capabilities were tested after replacing the water with 140°F liquid fat, which has different heating capacity, viscosity, and heat retention properties. With a few pumping adjustments, the heat tracing system proved to work flawlessly, as did the new pneumatic blower installed to clear fat from the line once pumping and discharge had been completed. The automation engineer was completely satisfied with the system’s performance and confirmed that it operated precisely as designed.