The fish feed extruder is a short-time high-temperature bio-reactor that can convert a variety raw materials into pellets to produce healthy and wholesome fish feed. This is a significant development in fish farming and contributes greatly to the advancement in aquaculture. The fish feed extruder is generally designed and manufactured with a hopper, barrel that houses the screw conveyor and the cutting knife. Sometimes, the electric motor supplies power to the machine. The use of fish feed extruders is increasing in popularity among fish farmers. There are many extruders available with different designs to produce fish feed. Let’s now look at dry types of fish feed extruders.
The steam boiler is not required for dry type single screw fish feed extruder. It is therefore cheaper and more efficient than wet extruder. Farmers prefer dry type extruder because of its practical and economic advantages. This is a detailed analysis of the dry type fish feed extruder.
The main frame of dry extruder includes the extrusion system, feeding system, and main electric motor.
Feed system
Maintain consistent feed flow rates Feeding system consists of three components: feed hopper and feed screw, as well as feed mixer.
- Feed hopper is where feed materials are prepared prior to extrusion stage.
- Feed screw: This screw is located in the bottom feed hopper and transmits materials from feed system to extrusion machine.
- Feed mixer: It is located in the middle of the feed hopper and works to mix and turn materials evenly.
Extrusion System
It is responsible to compress and cook materials before they go into the forming area.
- Extruder screw: The screw is located inside the barrel. Both the barrel and screw are made from alloy steel. They are treated with heat to ensure that they have a long service life and wear resistance.
- Extrusion generally involves high temperatures for a short period of time. To allow the feed to expand as it leaves the die, a temperature greater than 100 degrees Celsius is required. Dry extrusion produces high temperatures by dissipating mechanical energy from heated surfaces, such as barrels and screws surface. Shear forces between wall and material or material also play a role in the drying process. High temperature and high pressure can also kill salmonellosis, bacterial infections, and make the pellets easy to digest.
- The hole entry: This is a conical-shaped opening that allows materials to flow easily within the holes.
- It restricts product flow and causes the extruder to develop the necessary pressure and shear. You can choose from a variety of molds to produce pellets with different shapes and diameters.
- The cutter knife is an internationally recognized cutting technology. It is made up of sharp blades. It is designed to rotate in a circular motion on the die surface. This allows for small parts to be cut. You can adjust the speed of your knife to control the final pellet length.
Electric power system
Motors: Main motor, feeder motor, and cutter motor.