ProcessBarron’s very own Allen Ray, Director of the Air and Gas Handling Group, recently contributed his expertise to the World Cement Review by sharing his perspective on eliminating material buildup problems on preheater ID fans. To hear Allen’s perspective and to learn how you could start making material buildup issues disappear at your plant, read on!
The straight radial blade (ID) fan design has self-cleaning characteristics, which makes many people choose this design over others for dusty work environments, but is actually terribly inefficient to operate. Uneven accumulation of build-up poses the danger of damaging vibration at the bearings of the fan and possible failures.
In the cement-making process, draft fans are some of the largest parasitic loads. Starting in the ‘90s, high-efficiency, backward curved or backward inclined blade designs became more popular because of their higher efficiencies and lower power consumption.
From years of operational experience and testing these new fan designs, it was discovered that a backward inclined was best streamlined for laminar flow, reducing the accumulation of hard buildup of the front side of the blade over time. This wasn’t the end of the story, because the concave nature of the new blade shape made more opportunities for softer, powdery buildup on the back side of the fans.
Ideally, buildup on both sides of the blade would need to be eliminated. Since any level of material buildup leads to costly downtime, we had to go back to the drawing board.
ProcessBarron has developed a new system that has the potential to minimize, or even eliminate, the soft buildup on the back side of a backward curved blade. This reduces the costly downtime needed to clean the preheater ID fan rotor so your plant can stay up and running as long as possible.
The system that ProcessBarron developed involves using compressed air with high-energy nozzles to blast the buildup off of the blades with timed blasts or puffs released by a high-volume valve (or poppet valve). The system is simple, easy to install, and cost-effective. It follows the same concept as air cannons and consists of a cleaning lance, a compressed air reservoir or accumulator tank, and a poppet valve.
The air used for clearing the ID fans is stored in an accumulator tank, where the tank size depends on the size of the fan rotor to be cleaned. The larger the rotor, the more compressed air is needed to clean it. The frequency of the blasts of air for cleaning is dependent on the service and the dust loading.
For this solution, you will need a source of compressed air for cleaning, a source of filtered compressed air for instrumentation, an energy source, and a controlling mechanism.
Leaving the compressed air unfiltered and moist can be an advantage. The droplets in moist air will greatly expand when exposed to the hot gas stream, creating a small explosion that aids in the removal of buildup.
Success with These Systems
These systems have been installed in several plants across the U.S. and prove to be very successful in reducing or eliminating build-up problems. Any method of preventing downtime and lost production in this industry is extremely important, and these systems are a great way of doing that in cement production.
To learn more about these systems and how they could benefit your plant, contact the ProcessBarron team today.