It's no longer possible to imagine modern world no plastic products. About a third of all plastic products today are made from polyethylene. Along with the obvious benefits of its use, the search for effective ways processing and disposal of this polymer.

Polyethylene (accepted abbreviations - PET, PE) is a thermoplastic polymer that is widely used to create a huge number of products. Its use began in the 20th century: from the 30s it began to be used in the production of telephone cables, and from the 50s - as packaging in the food industry.

Today the list of PET products is huge:

• packaging film, bags, garbage bags;
• scotch;
• all kinds of packaging: bottles, cans, boxes, cans, containers, flower pots, etc.;
• pipes for sewerage and gas supply;
• electrical insulation, thermal insulation;
• storage devices, containers for liquid and solid chemicals;
• different kinds fencing, etc.

Depending on the technology, polyethylene is produced and used in modern industry different types and operational properties, for example:

• high pressure or low density (abbr. - LDPE, LDPE - a more plastic type of polyethylene, used for the production of film and cable);
• low pressure or high density (abbr. - HDPE, HDPE - has a more rigid and durable structure);
• polyethylene terephthalate (abbr. - PET, PET, PETE - used only for the production of disposable goods), etc.

What is polyethylene of different densities, and what types of packaging are made from it?

Manufacturing process plastic bags

Main types of polyethylene waste and where they come from

The popularity and mass consumption of PE lead to the fact that every day a huge number of used items made from it fall into the waste category:

1. Polyethylene products for household use. This includes packaging film, bags, bottles, vials and canisters. household chemicals, waste from medicine blisters and other items used by humans in Everyday life. All this is thrown away every day into ordinary garbage containers for solid waste (solid household waste). According to various estimates, the share of polyethylene in solid waste is about ten percent of the total volume.
2. PE industrial waste. This, again, is packaging film, all kinds of bags, waste plastic containers from stores (for example, food boxes), pipes, worn cable braids, etc.
3. Technological defects at enterprises producing PE products. Its volume can reach up to ten percent of all produced raw materials.

Polyethylene products are cheap and convenient. The most significant “disadvantage” of any type of plastic is the long period of natural decomposition of waste.

According to preliminary estimates by ecologists, the decay period in living nature polyethylene film or bottles is between one hundred and two hundred years old. This makes the threat of the death of all living things under tons of very real plastic waste in the near future.

Where can I take PET waste?

The bulk of household polyethylene waste ends up in ordinary garbage - solid waste containers located in the courtyards of residential buildings. A significant disadvantage of this disposal method is the severe contamination of PET with food debris, chemicals, dirt, liquids, etc. In the future, the total mass of waste will need to be sorted, and the plastic itself will require additional cleaning.

Important! An excellent solution today is to sort household waste at the moment of throwing it away, when plastic items are placed in specially designated storage areas.

Unfortunately, this method, which is very popular in European countries, takes root with difficulty in Russia:

1. Such containers are not yet available in every yard or even in every locality;
2. There is no working fine system for violating sorting rules, and as a result, even with such “distributors”, other types of waste often end up in the plastic bin.

You can donate PET waste:

1. To enterprises directly involved in processing PET waste, if they accept it themselves.
2. Recycling collection points operating in every city accept waste paper, scrap metal, plastic, etc. Payment for donating plastic will be a pittance, but in this way you will make your contribution to the cause of conservation environment.

What products are made from recycled polyethylene?

The raw materials obtained from the recycling of plastics are cheap and high-quality materials for the manufacture of a huge number of new useful products:

• waste with a short shelf life - bottles, disposable containers and packaging - are successfully recycled into similar products;
• Recycled granules serve as an additive to virgin polyethylene, for example, in the production of pressure pipes or large-volume containers;
• blown bottles, cans for food products and household chemicals are used for the subsequent production of drainage pipes, wood-polymer composites (they are used to make picket fences, decking boards, garden parquet, etc.);
• film waste from household waste, as well as used agricultural film, is usually processed into pellets for future injection molding products;
• Multilayer films as well as cable waste can only be recycled as additives for other granules, etc.

Depending on the type of PE product, as well as the area where it was used, the methods and equipment used for its recycling will vary significantly.

Recycling of PET products

What does the production of polyethylene waste recycling consist of? The full cycle will include several main stages:

Recycling polyethylene at home

Today, the possibility of recycling polyethylene at home occupies many inquisitive minds. For example, there are already developed methods for self-safe combustion of PET containers, offered by research assistants working in the field of ecology.

But there is an alternative view: when plastic is burned or even melted, substances harmful to humans and nature are released into the atmosphere. Therefore, independent burning or recycling of polyethylene waste is prohibited; such work can only be carried out by special enterprises with the appropriate license.

PET recycling

Speaking about recycling, today we often mean plastic recycling processes, when recyclable materials are “ new life"and is used for remanufacturing products.

Sometimes recycling refers to an alternative to recycling - the physical destruction of plastic waste or its storage in landfills and landfills. Since burning plastic is prohibited, other, more environmentally friendly methods are used to destroy it.

From the point of view of preserving the environment, it is highly effective, for example, the thermal decomposition of plastics at high temperatures in an oxygen-free environment.

However, a huge amount of plastic waste still ends up in city landfills.

Recycling PET waste is a promising direction in the economy, which is also supported by environmentalists. With the development of technology, recycling plastic waste becomes cheaper for the manufacturer, while at the same time making it possible to rid the planet of excess plastic, which is difficult to decompose. natural conditions. The environmental risks arising during the recycling process cannot be compared with the problems that humanity will face in the near future, since there are more and more landfills every year.

Millions of plastic bags are used and thrown away in Moscow every year. It turns out that some of them are successfully recycled. Today we will go to such an enterprise and find out how polyethylene is prepared for reuse.

The Moscow Region company "Expert Vtor" does not process all types of plastic bags, but only film, bags, bags, production defects of stretch film (the so-called shrink film) and LDPE.

LDPE is high-density polyethylene or, as it is also called, low-density polyethylene. LDPE waste can be generated during the direct production of polyethylene film. There is a lot of waste - in stores (packaging bottles, boxes, boxes), at glass factories (from packaging bottles, cans), at distilleries and beer factories (from packaging containers or finished products).

Stretch film is linear high-density polyethylene (LDPE). It can stretch a lot. Due to this property, as well as increased resistance to punctures and tearing, stretch film is used for packaging various goods, in particular on pallets. Stretch film waste is mainly generated and accumulated in warehouses of any size, at customs terminals, logistics centers, etc.

The company does not recycle popular T-shirt bags made of HDPE (low-density polyethylene) and “biodegradable” bags, which can be found, for example, in ABC of Taste. Polypropylene film, PVC film, bubble film, polyamide film, multilayer PVD+PP, PVD+PA films, as well as double-sided two-color films are also not suitable. Also, film contaminated with oils, fats, food waste and pesticides.

The collected polyethylene first goes to the warehouse. Up to 100 tons of film waste can be stored here, naturally in pressed form. At the first stage, the raw materials undergo careful sorting. Stretch is separated from LDPE, and types of films that cannot be processed by the enterprise’s facilities are rejected.

After sorting, bags of a certain color are put into a crusher. In it, using V-shaped knives (this type is also called “dovetail”), the film is crushed to particles of uniform size. The knives are driven by an electric motor.

From the crusher, through a pneumatic conveyor, the so-called “crushed material” enters the sink. In it, with the addition of special cleaning solutions, the “crushed” is cleaned of dust and other non-polyethylene inclusions.

The next stage of processing is agglomeration. The so-called “cooking” takes place in it. The operator loads clean “crushed material” into the working chamber through the loading window.

The raw materials fall along the guides onto the rotating rotor, are crushed by knives and, due to friction against the body and among themselves, are heated to the plasticization temperature. In this case, the entire volume of loaded raw materials becomes like a mushy mass.

When the material becomes homogeneous, “shock” water is added to it, as a result of which the material is sharply cooled and sintered into individual small balls irregular shape. The agglomerate is dried for some more time at natural ambient temperature and unloaded into prepared containers to go to the final stage. The cooking process itself lasts from 5 to 10 minutes.

The granulation process can be compared to minced meat through a meat grinder. The agglomerate that we obtained at the previous stage is loaded into the extruder hopper.

It is called so because the production of granules is based on the extrusion method - forcing the molten mass through a molding hole.

In general, the “minced meat” from the boiled bags is melted under the action of heaters and pressure created by a rotating screw. The polymer melt is forced through a filter into the rotating extruder head. Already from it come the so-called threads. To cool, they are passed through a water hose and then into knives, where they are cut into uniform granules.

The granules are packaged in clean polypropylene bags, approximately 50 kg each. Special conditions storage is not required, but it is advisable that it be in a dry room. The resulting granules, depending on the composition and color, are sold. Stretch granules of natural color are used for the production of secondary stretch.

LDPE granules of natural color are used for the production of secondary shrink or technical film. Colored LDPE granules are mainly used for the production of garbage bags.

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Plastic bags and film

Additional Information:

Types of plastic bags and films.

• polyethylene(marking 02, HDPE, HDPE and 04, LDPE): polyethylene comes in high and low density (low and high pressure, respectively). If there is no marking, then you can distinguish one material from another as follows: thin rustling packaging bags and most “T-shirt” bags are 02. Soft, oily bags, greenhouse, stretch and bubble film are 04.
• polypropylene(marking 05, PP, PP): most often this packaging is shiny and “crispy”, easily torn, and does not stretch. Cereals, pasta, bread, cookies, etc. are packaged in polypropylene. Opaque wrappers from chocolate bars are also PP with added dye; such packaging is more difficult to recycle, so it is not accepted everywhere.
• combined plastic(marking type C/xx or 07/other)
• biodegradable And pseudo biodegradable
• polyvinyl chloride(PVC, PVC, 03)

Where can I recycle plastic bags?

We do not accept all types of packages. Accurate current list look at our instructions!

• bags: packaging, T-shirts, ziplock, for shopping
• film: bubble, greenhouse, stretch
• spandbond bags
• "sugar" bags and similar bags, bags
• foamed polyethylene
• with markings:

02, HDPE, PVD, C/02, C/HDPE
04, LDPE, HDPE, C/04, C/LDPE

How to return bags and film?

1. independently to the collection point of the Collector
2. order a Collector
3. at the rallies of our movement, from which we take it to the Collector’s warehouse

We do not accept for processing from individuals:

• “biodegradable” plastic;
• polyvinyl chloride (PVC/PVC/03);
• plastic 07.

On this site we collect bit by bit information on where to submit rare species recyclables and things. We keep the data up-to-date and check reception points if they cause you mistrust.

Most of our activities are supported by volunteers, but in order to structure the information, monitor its updates and maintain the operation of the site, we need daily work content manager Please, so that we can continue to provide up-to-date information for you!

Polyethylene granules

Polyethylene is an organic compound that is a polymer (a substance with a large molecular weight, consisting of long macromolecules) of ethylene (a flammable, colorless gas with a faint odor). Formed as a result of the polymerization process of ethylene. Occupies the largest share among plastics. Industrial production polyethylene began in the mid-20th century. Often people try to hand over polyethylene by mistake, confusing it with polyethylene rephthalate (PET). However, these are different substances, and their disposal or recycling processes occur differently. They are also taken separately.

And polyethylene is often confused with cellophane, not realizing that these are completely different substances. Cellophane is a wood pulp processing product.

Everyone is familiar with polyethylene products. Their number is very large and is constantly growing, because this material is quite cheap, easy to use and has many applications. And if you hand over polyethylene waste for recycling, you can obtain secondary raw materials from it.

Types of polyethylene

Types of polyethylene materials There are quite a few types of polyethylene. Moreover, despite the fact that the basis for their production is the same base material (namely, polyethylene granules 2-5 mm in size), each variety has its own special qualities and they are all considered completely different substances. But the processing of polyethylene occurs in the same way, regardless of its type.

It is customary to distinguish different types of polyethylene based on its density.

High-density polyethylene (HDPE)

Bags made from LDPE

It is also commonly called low-density polyethylene. It is obtained by polymerizing ethylene using a tubular reactor or autoclave.

Low-density polyethylene (HDPE)

HDPE pipes

It is also commonly called high-density polyethylene. It is manufactured using three technologies: gas-phase, suspension and solution.

Medium pressure polyethylene (MDP)

Packages from design documentation

PSD is obtained by mixing LDPE and HDPE in certain proportions.

Linear high-density polyethylene (LDPE)

Soft and elastic material obtained by the most complex polymerization method.

Cross-linked polyethylene (PEX)

Has a high molecular weight. PEX is obtained from HDPE by cross-linking its molecules with ionizing radiation at elevated pressure.

Foamed polyethylene (polyethylene foam, PP)

Products made from PP foamed polyethylene are produced using foaming technology with a special mixture.

Chlorosulfonated polyethylene (CSP)

High elasticity material. CSP is obtained by reacting polyethylene with chlorine and sulfur dioxide.

Ultra-high molecular weight polyethylene (UHMWPE)

Super durable material. UHFMP is produced at low pressure with a high degree of polymerization.

Application of polyethylene and its properties

The main product of LDPE is canisters of various volumes

PVD

LDPE is characterized by increased plasticity, high level melt flow and low tensile strength.

PVD is the most common packaging material. It is used to make bags and wrapping film. Products made from LDPE are glossy, do not rustle, and have a beautiful appearance.

Recycling plastic bags allows the material to be reused.

HDPE

A fairly hard product, with a density of 0.95 g/cm³ (or higher). It has good strength and slightly elongates when broken. Resistant to low temperatures(withstands frost down to -50°C). Does not allow moisture to pass through, and is resistant to fats and oils. Does not emit toxic substances, therefore safe for humans.

Canisters, waste containers, containers for solvents, etc. are mainly made from LDPE.

PSD

Has good resistance to breaks or impacts, cracking and scratches. The characteristics are similar to HDPE.

Shopping bags, sacks, shrink and regular films, screw caps, etc. are made from PSD. Since all this is common in households, the question often arises - where to donate polyethylene? For this, there are collection points or simply special containers.

LPVD

Its properties are similar to HDPE, but it has the highest physical and chemical properties. Puncture resistant and withstands both high and low temperatures.

From LLDPE it is possible to obtain a thinner film than from HDPE. Packaging films, lamination films, etc. are the main areas of application for LDPE, although it is gradually replacing LDPE. LDPE films can be used for packaging hot products.

PEX

PEX water pipes

It is characterized by high strength and heat resistance, does not spread when heated.

The scope of application of cross-linked polyethylene is pipes and various parts for water supply, heating, pipelines.

PP

Properties of this type of polyethylene: it is characterized by a smooth surface, has a finely porous structure, good elasticity and resilience. Has excellent biological and chemical resistance. Durable. Weakly absorbs moisture and conducts heat poorly. Ecologically pure. Safe for humans.

It is used primarily in construction (for thermal insulation and other needs).

HSP

The properties of CSP resemble rubber. Has the ability to vulcanize. It has high chemical and atmospheric resistance and tolerates high temperatures. It is not affected by alkalis, acids and strong hardeners.

Paints and varnishes, adhesives, and sealants are made from CSP.

SVMP

SVMP is a very durable material intended for use in extreme conditions. It has high frost resistance, is resistant to impacts, friction, corrosion, and abrasives.

The scope of application is very wide. SVMP is good wherever ultra-strong fibers are required (medical materials, Sports Equipment, armor protection, protective coating for any structures and elements).

Equipment for polyethylene processing

Now in Russian cities There are many places where you can donate polyethylene quickly and easily. Many companies purchase it to send it to processing plants. You can also equip your own processing line. Such a line, when fully equipped, includes the following equipment:

• washing machine;
• crusher;
• centrifuge;
• drying installation;
• agglomerator;
• granulator;
• extruder

A pneumatic conveyor, as well as a conveyor, will help increase the efficiency of the work process - with their help, the supply of raw materials is accelerated and improved.

The key processing device is the agglomerator. It is he who, when exposed high temperature forms secondary raw materials - agglomerate - from polyethylene waste. Subsequently, finished products are produced from the agglomerate.

The granulator may be part of the processing line, but in some cases you can do without it.

Polyethylene is recycled by burning it. The main disadvantage of this technique is the toxic substances released during the combustion process. It is necessary to apply increased safety measures to avoid environmental pollution.

Recycled polyethylene products

Plastic trash bags are a recycled product

Instead of recycling plastic bags and other products made from this material by burning, it is much more profitable and efficient to send them for recycling. The features of this process are:

For the first time, polyethylene products can be recycled without any restrictions. But the number of subsequent processing is limited by certain conditions, because the quality of the material begins to gradually decline. It is possible to produce any products from polyethylene recycled several times only if the requirements for these products are significantly reduced.

Various companies produce film and other materials made of polyethylene, planning to make money on it, but we must not forget that the quality of the material decreases not only due to multiple processing cycles. The deterioration of the properties of polyethylene products is also affected by exposure to direct sun rays, temperature fluctuations, as well as some other operating conditions.

It is worth taking into account this feature: products made from polyethylene secondary (for example, bags) may not be too inferior in their parameters to the primary ones, but at the same time they can be purchased at a very attractive price.

Recycling of bags and other polyethylene products is carried out according to the following scheme:

• sorting;
• washing;
• splitting up;
• centrifugation;
• rinsing again;
• drying;
• heat treatment.

Polyethylene collection points (80 cities)

Video: Polyethylene processing plant

Most types of plastics do not decompose in nature or decompose extremely slowly - over hundreds and thousands of years. Therefore, by the 1970s, the world had already faced the problem of environmental pollution with plastic waste - and, accordingly, the issue of recycling such waste. It soon became clear that recycling plastic waste could be a business in itself with a fairly attractive margin level.

Today in Belarus there are about 100 organizations processing plastic waste. As a result of processing, prepared secondary raw materials are obtained (crushed, granules, flakes according to plastic brands) for the further production of new plastic products and packaging.

Industrially processed in Belarus the following types plastic waste:

• packaging with PET, PETE, HDPE, LDPE, PE, PP symbols. These are plastic bottles for milk, oil, vinegar, beer, containers for shower gels and shampoos, other cosmetics, household chemicals;
• plastic bags and film;
• plastic basins, buckets;
• pens without rods, rulers;
• plastic woven bags, etc.

The demand for “recycled” plastic is quite high, and this has led to the fact that companies that process plastic waste are no longer satisfied with household and industrial waste, but buy unnecessary plastic - primarily plastic (PET) bottles.

According to the State Institution “Operator of Secondary Material Resources”, there are several collection points for PET bottles in each district of Minsk. You can select the nearest stationary collection point for plastic bottles by following this link. The operating hours and cost of delivering a kilogram of plastic waste are also indicated there.

Important point: You must bring at least a kilogram to the collection point plastic bottles, otherwise they will not be accepted. If you only need to dispose of one or two bottles, then it is easier to throw them in the trash, observing certain conditions:

• Used PET bottles should be disposed of in visible yellow containers that are designated for separate collection recyclable materials;
• Plastic bottles can be disposed of in containers labeled “plastic, glass, paper,” “plastic, paper,” or “plastic, paper, metal.”

In addition to PET drink bottles, the following can be thrown into separate waste collection containers:

• bottles from vegetable oil, vinegar, dairy products;
• plastic packaging for shampoo, hairspray, shower gels and other cosmetics;
• packaging for household chemicals, various detergents;
• plastic bags, containers for food packaging;
• bread bags, milk bags, jars of yogurt, kefir;
• household items made of plastic (buckets, basins, etc.);
• plastic parts, housings of household appliances.

However, there are a number of packages that should not be thrown into plastic containers. This list includes Tetra Pak, toothpaste tubes, mayonnaise, chips, and tea packets. Such packages contain not only degradable plastic, but also metal, which must be disposed of separately. Therefore, throw away tubes and packages of chips in a common container - this garbage will be buried in a landfill.