RU97057U1 - FILTER ELEMENT FOR THIN CLEANING OF RAW MILK - Google Patents

Abstract

 The filter element for fine purification of raw milk, made in the form of a tubular cartridge made of food-grade polymer material, formed by discrete rows of fibers obtained by aerodynamic extrusion with pore sizes radially decreasing from the periphery to the center, characterized in that each row consists of frame and filter fibers moreover, the thickness of the filter fibers is greater than the frame.

Description

The utility model relates to techniques for the separation of liquids and gases, namely, to removable cartridge filters for cleaning dairy products.

To obtain high-quality products, it is necessary to clean milk from all types of mechanical impurities, not only with solid particles, but also with plastic, as well as mucus clots. The difficulty in solving this problem lies in the fact that milk is a multicomponent substance, which, being a liquid, essentially contains both useful parts (milk-fat "balls") and harmful ones. The harmful components of raw milk are also heterogeneous. It can be large grains of sand, stones, parts of the feed, straw, etc., or it can be the smallest particles of soil and manure (dust), which, when dissolved in milk, carry a serious bacteriological load. On the other hand, they pollute raw milk and mucus clots, which are formed in animals due to various diseases.

The prior art filter element for fine purification of raw milk, made in the form of a tubular cartridge made of food-grade polymer material formed by discrete rows of fibers obtained by aerodynamic extrusion with pore sizes decreasing radially from the periphery to the center (see patent RU 53585, cl. B01D 27/08, published May 27, 2006). A disadvantage of the known device is that it does not allow milk to be purified from fine impurities. Filtering is carried out according to the principle: if the particle is less than the pass-through channel of the filter element, then it is skipped, if more, it is delayed. Such devices purify raw milk only from larger impurities than the milk-fat “ball”, finer impurities freely penetrate the filtered raw milk and inseminate it.

The objective of the utility model is to eliminate this drawback. The technical result is to improve the quality of cleaning. The problem is solved, and the technical result is achieved by the fact that in the filter element for fine purification of raw milk, made in the form of a tubular cartridge made of food-grade polymer material, formed by discrete rows of fibers obtained by aerodynamic extrusion with radially decreasing pore sizes from the periphery to the center, each row consists of frame and filter fibers, and the thickness of the filter fibers is greater than the frame.

The proposed device is a rigid polymer cylinder made by aerodynamic extrusion of food grade polypropylene grade 01030. The main advantage of this material is its resistance to aggressive environments, as well as the ability to stretch threads with a thickness in the range from 0.01 mm to 0.02 mm at a melting temperature 195 ° C. The method of aerodynamic extrusion allows you to get a change in the size of the transmission channels with a decrease from the periphery to the center. A feature of the proposed filter element, in contrast to previously existing products, is that in the manufacture of technologically discrete layers are introduced, where the polymer fibers are heterogeneous in thickness in one row. Thin threads strongly pressed against each other form a filter frame, which allows preserving the geometry of the filter element under pressure and filtering out coarse particles of contamination. Thicker filaments form the filter body, which removes fine dissolved dirt, which is partially concentrated under the influence of centrifugal forces. This feature allows you to achieve effective cleaning of milk from both large and small impurities, while ensuring unhindered passage of massive milk-fat balls through the filter. The filter element receives heterogeneous, with transmission channels gradually decreasing from the periphery to the center, and discrete changing layers that create disturbances in the flow of raw milk passing through the filter element, thereby further improving the quality of the filter.

The filter element is made on a machine consisting of an extruder and a carriage, as follows.

Polypropylene granules are poured into the extruder bunker, where they are fed with the help of a screw into the melting chambers, which consist of two stages. In the first stage, the substance is partially crushed and melted to a viscous state. Further, at the second stage, polypropylene is melted to a fluid, but not boiling state, to a plastic-homogeneous mass, which is fed by a screw into the aerodynamic head of the extruder. The screw has the shape of a spindle, narrowed at the beginning and expanded to the end. Only due to this design of the screw it is possible to achieve the necessary pressure of fused polypropylene at the exit of the die.

Heated air, spiraling in a spiral, is supplied to the aerodynamic head of the extruder under pressure, which inflates the molten mass of polypropylene supplied by the screw into the ring. The melt supply temperature should be 175 ° C. At a higher temperature, layers are welded, and at a low temperature, their separation, narrowing of the ring and thickening of the threads. The optimal ring has a diameter of 6-8 cm and is located at a distance of 18-20 cm from the die. The air pressure on the polypropylene melt is kept equal to 0.3 kg / cm ² . At a lower pressure, the fine filter for milk is soft, light and porous, and at a higher pressure, it is solid, dense, and heavy.

Under the influence of aerodynamic forces, the thread is twisted into a ring, which is wound on a mandrel. The mandrel is located on the carriage and is driven by the engine only clockwise. Rolling is used to obtain thin threads. Only in this way can fibers be obtained with a thickness of 0.01-0.02 mm. Speed and rotation of the mandrel are strictly limited. When the speed and rotation change, the density of the polypropylene melt spraying changes radically, which affects the porosity of the fine filter of milk. Failure to comply with the above parameters during production makes the filter unsuitable for high-quality filtration of raw milk.

The proposed filter element, made in this way, can be installed on any type of milking equipment, provides high quality cleaning of raw milk (increase in commercial grade), is quickly replaced, extremely easy to maintain and cheap (no more than 2 kopecks per liter of milk).

Claims (1)

The filter element for fine purification of raw milk, made in the form of a tubular cartridge made of food-grade polymer material, formed by discrete rows of fibers obtained by aerodynamic extrusion with pore sizes radially decreasing from the periphery to the center, characterized in that each row consists of frame and filter fibers moreover, the thickness of the filter fibers is greater than the frame.