In the pet and fish food sectors the term “wet extrusion waste” denotes the solid or pasty matter that is produced each time the extruder starts up and stops, as well as the samples of croquettes and flour taken from the system during production. The disposal of this type of waste is usually entrusted to specialized companies in specialized treatment centers. The amount of this type of waste produced on a daily basis depends on the type and productivity of the extruder, the operator’s ability to manage the system and the number of start-ups due to change of formula, shape and colour etc. As an example, if each stop/start-up of a 6/7 ton/h extruder generates a quantity of waste of 80 < 100 kilos, there is consequently an economic loss of approximately €ur 35 < 40. Given an annual production of 30,000 tons in batches of 25,000 kg, 1,200 start-ups are performed with an overall loss of €ur 40,000 < 45,000.
CRISTIANO TORRE Engineering has designed a system able to recycle all this waste perfectly thereby recovering costs in full.
Waste is loaded manually or automatically into the treatment tank; water is added according to a determined formulation; there is a thorough grinding/dispersion of the mixture by means of a cowless disperser with variable speed which then gradually transfers the mixture obtained in the preconditioner upstream of the extruder during normal production, by means of a volumetric pump with variable speed. The dissolution formula, the process of dispersion, the maintenance of the density and the flow of the mixture to the preconditioner are all managed entirely automatically by a microprocessor by means of a weighing system and a flow meter. The flow of the pump is adjustable allowing the constant unaltered maintenance of the quantity of water necessary for the process of extrusion independently from the quantities of solids added for disposal. The tank is washed automatically at the end of each disposal cycle. Given that operating an extruder is a source of environmental pollution due to the content of waste waters (TSS, COD, BOD5), our system guarantees a notable reduction in pollution and consequently a reduction in cost.
Operation of the system entails:
- THOROUGH GRINDING AND HOMOGENOUS DISPERSION
- ABSENCE OF RESIDUAL PRODUCTS
- NO INTERFERENCE WITH OPERATION OF EXTRUDER
- NO ORGANOLEPTIC ALTERATION OF PRODUCT