AQUACULTURE FISH FOOD PRODUCTION

AQUACULTURE FISH FOOD PRODUCTION

            Formulation of the foods used in aquaculture are varied according to fish species, the habitat (freshwater, saltwater, brackish water), life phase (larvae, juveniles and adults) and fish's nutritional needs. Best method in the world for digestible quality feed production is Extrusion. Extrusion Method is compressing, shaping and cooking of the feed under the high pressure condition.

Aquaculture fish feed production processes may be classified as;

Raw Material Supply

Dosing

Grinding

Homogeneous Mixing

Extrusion

Drying

Oil Adding and Flavoring

Crumbling and Sieving

Packaging

Raw Material Supply

            Raw materials used in aquaculture fish feed rations are obtained from domestical or international supply companies. Raw materials quality and bringing in some certain procedures in accordance with the maintenance is very important. Also, preservation of raw material is important and can deposited in various types and sizes silos.

Dosing

            Raw materials which will be prepared by the formulation of the feed for species sent from the silos to grinder system for grinding via by screw or belt conveyors.

Grinding

            Grinding process is an important step to obtain high quality extruded feed. Grinding of raw materials to micron particle size directly influences the quality of pellets.

            Grinding system machines are in various types. Standard Grinding Machinery is considered as "First Generation" and suitable for making large amounts of grinding, hammer mill is used for grinding of granular grains.

Fine Grinder Machine is considered "Second Generation" has a new advanced design hammer, its suitable for making finer grinding that can be used in feed, food industry, environmental protection and chemical industry.

Micro Grinder (Micro Pulverizer) machine which is considered last generation, suitable for making micro-milling, feed, grain, food, environmental protection and chemical industries. Grinding range can be set between 10-100 micronmeter, this types grinder essentially used in micro-pulverized fish feed production.

Homogeneous Mixing

            The homogeneous mixing process is very important step for obtaining microparticulated feed that ensure every feed particles have a homogeneous nutritional value. Therefore, mixers are one of the system equipment required for homogeneously mixing of the raw materials.

Grinded and homogeneously mixed fish feed raw material mixture can be stored in a seperated silo.

Extrusion Process

            Fish feed raw material mixture from the silo to the Conditioner machine sent by  screw conveyor. Fish feed raw material mixture is tempered and mixed with water in certain proportions of water in the conditioner and obtained raw dough mixture is sent to the extruder machine. Conditioner and Extruder are important extrusion system equipment that supporting each other. Raw material-water amount incoming to conditioner is adjusted by screw conveyor rotation speed and water dosing pump, thus intended to achieve a uniform mixing.

Raw dough mixture incoming from conditioner to extruder machine is compressed and baked in the extruder under high pressure conditions by double or single screw system of extruder machine. It is cut with special knives located in the extruder output. Outgoing pellets are shaped depending on blade speed and extruder machine speed.

The extruder system has two types including single and double (twin) screw. Twin Screw Extruder, Twin screw extruder is suitable for ripening and molding various kind of dog food, aqua feeds, meat analogue etc., and for treating some products which cannot be processed by a single screw extruder. With the changing arrangement of the segment (mixing elements, kneading elements and steam block), extruder can meet the needs of different products. Extruder is controlled by an independent control panel.

Extruder System consists of the following parts:

• Conditioning (Feeding) system
• Extrusion system
• Cutting system
• Lubrication system

1-3 mm diameter pellets from extruder to multilayer dryer are transferred by Pneumatic conveyor through blower machine, bigger than 3 mm pellets are transferred by belt conveyor. Pneumatic conveyor system helps with created the strong airflow for pre-cooling of the pellets from the extruder, both moved in closed area to the multilayer dryer.

Drying Process

Dryers are 3 types, electric, gas and steam. Drying process are performed adjustable speed of 5 layers as required of the pellets.

Pellets are dried in the multilayer dryer at the desired temperature with the thermostat setting and sent to Flavoring Machine by a belt conveyor for oil adding.

Oil Adding and Flavoring

Flavoring and Oiling drum is used for oiling or flavoring of fish feeds and consist of a two cylinders with adjustable rotation speed and a temperature controlled oil tank.

Pellets coming from dryer to Flavoring line are sprayed oil / aroma with a dosage pump and drums are rotated at a certain speed for maximum homogeneous mixture.

Pellets are carried by cooling conveyor and stored at silos after flavoring process and rested in the silo for 1 day then packaged.

Crumbling and Sieving

Feed pellets from the silo break in Crumble crushing machine for obtaining smaller than 1 mm. Crumble machine breaks pellets with adjustable roller width as desired size.

Broken pellets are sieved Vibrating Sieve Machine for seperation of sizes (micron/mm) and dusts of the pellets eliminated and obtained different sizes microparticle fish feeds.

Microparticle feeds are packaged and ready for use, this step can achieved quickly, economically and untouched with rapid packaging machines