At present, I am engaged in the design of an aquafeed plant and have encountered challenges during discussions with companies regarding the flow diagram of the facility. There are conventional/standard questions that precede system design, such as: What is the capacity? What type of feed do you plan to produce (high lipid, sinking pellet, floating pellets, etc.)? What will be the raw materials and formulation design? And so on… These aforementioned questions are merely the beginning of subsequent question sets. However, it is essential to note that each extruder supplier has their own standard flow design, from raw material intake to packaging. Each extruder supplier may offer unique features and advantages in their flow design, catering to specific industry needs or production requirements. The choice of raw materials and formulation design can significantly impact the final product quality and production efficiency. It is crucial to thoroughly evaluate and compare different suppliers’ offerings to ensure the selected extrusion system aligns with the intended production goals and constraints.
Designing a flow diagram for aquafeed production involves several stages that transform raw ingredients into a nutritionally balanced feed for aquatic animals. The key stages in the flow diagram include ingredient selection, grinding, mixing, conditioning, extrusion, drying, cooling, coating, and packaging. The complexity of the extrusion process extends beyond equipment selection, encompassing factors such as the precise control of temperature, pressure, and residence time within the extruder barrel. These parameters can be fine-tuned to optimise the gelatinisation of starches, denaturation of proteins, and overall texture development of the aquafeed pellets. Additionally, the post-extrusion processes, such as drying and cooling, play a critical role in determining the final product’s stability, shelf life, and palatability for the target aquatic species. In this context, the following approach can be utilised to structure the flow diagram to facilitate sustainable and economically viable aquafeed production.
Aquafeed Production Flow Diagram Steps:
Raw Material Reception: Raw materials such as fish meal, soybean meal, sun flower meal, wheat, corn, SPC, DDGS, vitamins, minerals, etc., are delivered to the plant and animal rendering by-products. Standard quality assessments are conducted for moisture content and nutrient levels, along with contaminants. Regarding raw materials: how many ingredients are intended for use in the formula? This will correspond to the number of storage silos required.
Storage and Weighing: Concerning this stage: What type of silo is utilised? What is the full capacity? Is there one shift or three shifts per day? Will only meal or grain itself be used?
Grinding: Will only a micropulveriser be employed, or is coarse grinding necessary? What will be the particle size (e.g., 200 μm or 400 μm)? What type of sieve is required after grinding, and is a by-pass system necessary post-grinding?
Mixing: Is a standby connection required after mixing? What will be the mixing capacity?
Preconditioning: How is steam or water quality controlled? What will be the capacity of the silo above the preconditioning unit?
Extrusion/Pelleting: What is the production capacity per hour? What will be the capacity of the silo above the extruder? How is the extruder process time, batch and flowing period for the compressed dough to be controlled?
Drying: What is the expected moisture content of the final product? Will you sieve the small particles as rework to the grinding stage?
Cooling: Is cooling required before or after drying? Will you sieve the small particles as rework to the grinding stage?
Coating (Oil Addition): Will oil sources be added in one or more consecutive stages? Is the addition of other liquid additives planned at this stage? If so, what is the temperature resistance of these additives?
