Operation effect fish feed extruder output
We will now talk extrusion rules, the equipment (hardware) and the operation of the same (software). Let's see how the extrusion system can handle variations in food formulations. The current trend is to use more and more vegetable proteins and this has an impact on the extrusion process. Normally, when you add more vegetable protein, the process will require more water and the more water in the system, the more energy is needed to perform the cooking, since the water acts as oil and reduces friction.
Old models of preconditioners provided a bad experience when trying to add a high amount of water to the dough. This resulted in a sticky mass that often clogged the pre-conditioner. Current technology makes it possible to work with high humidity in the conditioner, as well as the addition of steam and other moist ingredients, such as fish processing residues. In fact, these residues have a high PDI, making them ingredients that offer a desired binding effect. The limits for this inclusion vary between 15 and 50%. There are systems that make it possible to mix dry raw material such as soybean or wheat bran, with the use of 80 to 90% wet animal protein residues, for the processing of a raw material with high protein and good binding properties.
High Intensity preconditioner as well as the High Shear Conditioner are projects that incorporate improved technology in the control of high intensity mixtures, retention time and liquid inlet system, increasing the capacity for adjustments of any range formulation. HIP is best when you want to add a lot of meat to the conditioner.
The fish feed extruder cannon is where the energy inputs are finalized. Conditioner improvements raise cooking levels by 50% and even more in some cases. This allows for variation in the way the final cooking is transmitted to the different aquatic food formulations. Different forms of energy supply can be achieved due to configuration changes, changes in matrices, use of cooking control devices, such as counter-pressure valves, complex matrices and all types of energy inputs. In some cases, the flow rate of the extruder must be reduced to provide an increase in the energy supply. This energy input is often referred to as SME or specific mechanical energy.
The equation needs a little bit of definition to be used. Actual load is the engine load when running and the idle load is when the machine is running empty. The actual speed is the speed of the extruder shaft when in operation, and the base speed is speed when the motor of the extruder shaft is running at 60Hz. For a constant speed motor this index is 1. Available motor power is the rated power of the extruder motor in kilowatt. Mass flow is the flow rate of the extruder. Once the equation is solved, divide it by 3.6 to get the value in kWhr / ton.
When you play with the equation, you can see that increasing the engine load exponentially increases the specific mechanical energy. Always check with the extruder manufacturer to see if you can increase the power of the motor. Continuing to use the specific mechanical energy formula, we found that by adding more water to the conditioner, making the mass more liquid, the specific mechanical energy decreases, because the water will act as a lubricant, decreasing the load on the engine. In order to maintain the same level of cooking, we have to maintain a balance between the parameters of the conditioner and the extruder gun.
The result is a final product with the desired characteristics. Raw materials, system configuration, operating parameters and final product specifications can be adjusted by the system. A question that must be asked and accounted for is, “If high temperatures, better sources of starch and more water are needed to cook raw materials with low quality proteins, how much does it cost to extrude and dry these ingredients when compared to buying one? raw material with better quality protein? ” These calculations can and should be done to see the best and most cost-effective approach. Higher temperatures and more water generally mean less capacity (lower feed pellet machine flow), as well as more energy use.
Having your process under control is the key to a properly extruded food.