CLIENT: Multinational Animal Feed and Nutrition Supplier
PROJECT: $50MM Existing Plant Renovation including new Automated Weighing & Dosing System addition
BACKGROUND: After a qualification-based selection process involving several leading engineering companies, the client selected ADF Engineering to convert a newly purchased decommissioned Pet Food facility into a state-of-the-art facility for the production of animal feed premix. The client considered installing an Automated Weighing & Dosing System (AWDS) to provide accurate and efficient mixes and meet their customers’ stringent quality requirements.
- The existing product storage bins were not designed for heavier materials.
- Tight layout in the existing building required extreme accuracy for new material handling equipment.
- The AWDS system works as a vertical arrangement. Several layout options needed evaluation to determine what would work best with the existing structure.
- The AWDS uses a rail system for the moving tote stations on multiple floors. The deflection criteria of these floors are extremely strict to limit wear on the units and ensure the mixes’ accuracy.
- Due to restrictions in the equipment layout, several columns in the new tower needed to be staggered and were unable to remain continuous for the structure’s full height.
- To provide efficient batch blending, a large quantity of ingredients had to be available on site. This presented complex challenges for placement and storage.
- Constructability was a significant factor in the design. The necessary materials removal for demolition and entry of new construction materials into the existing tower was limited. The new tower and its foundations required installation in a portion of the existing warehouse area.
The project layout was a blend of both Brownfield & Greenfield designs. It was comprised of renovations to the existing process tower to maximize its storage capacity and raw ingredient intake, in addition to a new 150′ tall, adjacent tower to house the AWDS system. The design of this new arrangement included:
- Laserscanning and precision 3D modeling used in the design stage to avoid interference around existing equipment and structural elements.
- Evaluation & structural reinforcement of the storage bins and bin support floor in the existing tower. The ingredients for the new premix plant have a much higher density than the original bins’ tolerance. The bin bottoms were replaced, and additional steel was added to the floor to support this extra load.
- Locating and designing several new openings in the slip form concrete wall of the existing tower to allow for conveyance between the old and new structures.
- Removing and replacing several working platforms at different elevations for a new conveyance layout in the existing tower.
- Using heavy truss sections in the new tower to support non-continuous columns from the floors above.
- Design of floor systems with an allowable live load of 60 – 200 psf using both checkered plate and elevated concrete slabs on metal deck.
- Design unique rail support details for transfer totes.
- Design of a complex lateral force resisting system to transfer wind and seismic loads down the tower without interfering with moving equipment.
Process design of the AWDS system included:
- Sizing the systemwas critical to maintaining the flexibility of multiple formulations while allowing for a wide range of batch sizes to be blended with consistent quality and accuracy.
- Developing specialized “mass flow” bin bottoms to ensure consistent batch blend from the beginning of the process to the packaged product.
The design option of a combined new tower and renovated existing structure allowed for the correct balance between cost savings and flexibility.