INNOVATIONS IN STORAGE SILO FLOOR DESIGN AND OPERATION

Everything we see and read about today somehow relates to saving the environment. The new "buzz" phrase we hear is "Go Green" when developing new projects. The goal is to design systems to operate at reduced energy levels and reduced filtration requirements while simultaneously improving their performance. In 2005, Lafarge Canada Inc. installed two storage silos with innovative fluidized floor designs for material discharge at their Richmond, B. C. plant. These silos would store flyash and cement. The method of discharge would prove to reduce power, decrease vent requirements, allow material to discharge in a less fluid, well-regulated flow state and ensure complete repetitive emptying. In addition to reducing power consumption during plant operation, it was determined that flyash bulk-trailers were loaded to capacity in less time than with previous systems, thus improving the truck supply capacity for this product. Approximately 40% more capacity was able to be transported by each truck for both flyash and cement increasing throughput, but reducing the number of trucks required per day. Another tangible and unique result of this floor design is the improved homogeneity of these two products over any other types of storage in place on the market. This paper will provide a look at the silo floor aeration design and the method of withdrawal that reduces the power consumption by a factor greater than 10 times. Imagine a storage silo with complete coverage of aeration pads on the silo floor, being fluidized and withdrawing product using less than 25 HP during normal operation and less than 40 HP for near 100% discharge during the cleanout cycle of the 10,000 Mton cement silo. This after almost five (5) years of continuous operation. As a leader in cement production, at the Richmond plant, Lafarge began "Going Green" as early as 1996 with innovations in homogenization silo design and material withdrawal, continuing in 2005 with storage silo designs with reduced energy consumption and improved truck traffic, contributing to a cleaner environment.