HDPE plastics are produced from a component of crude oil, naphtha, which is cracked (heated at very high temperatures) in order to extract the ethylene gas which is released when the chemical structure of naphtha deteriorates. The ethylene gas is then polymerized, a process which involves the free gas particles joining together to produce long chains of ethylene molecules.

There are many different types of polyethylene. HDPE is a particular type of polyethylene with a very dense linear structure which gives it an increased tensile and molecular strength. HDPE is normally defined as being polyethylene with minimum density of 0.941 grams per cubed centimeter. Within the category of HDPE plastics, molecular weights range from 100,000 to 500,000, which is where the great variance in HDPE grades arises. Common grades of HDPE plastics include blow molding grade HDPE plastics, injection molding grade HDPE plastics, film grade HDPE plastics, and pipe grade HDPE plastics. Each of these grades have slightly different physical properties, the most notably important one being MFI, or melt flow index. Melt flow index describes how quickly the HDPE plastic flows when in liquid form, applications such as pipe making and blow molding require a highly viscous slow flowing HDPE plastic, whereas injection molding requires a quickly flowing HDPE resin.

HDPE plastics were first invented in the 1950’s, though it took some time to discover ways to reliably produce large amounts of homogeneous HDPE, as the processes under which HDPE is produced must be tightly controlled in order to produce the different grades of HDPE.

Ethylene naturally polymerizes at high temperatures and pressures, but it is not commercially viable to operate facilities under these conditions. So instead, catalysts are used to lower the temperature at which polymerization will take place, and also direct the type of polymer which results. HDPE’s largely linear structure with little molecular branching is commonly produced by Zeigler-Natta catalysts, or chromium catalysts.

HDPE lends itself well to recycling, and a great deal of reprocessed HDPE, recycled HDPE, and regrind HDPE is available on the market. The bulk of recycled HDPE plastics are post consumer scrap reclaimed from kerbside recycling programs. Millions of tons of HDPE plastic milk bottles and other household vessels are collected and recycled every year. For the most part, recycled HDPE plastics are equally as useful as virgin HDPE plastics, though they may not be used in food contact applications. There is some risk that contaminants found in the scrap HDPE from which recycled HDPE is made may pass through the various cleaning and filtration steps and degrade and contaminate the end product. If one is dealing with a reputable supplier, and the specific application is not overly intensive, recycled HDPE is an economically sound alternative to virgin HDPE plastic.

HDPE Plastic Supplier

We source HDPE material from several manufacturers world wide. Please contact us through the form below and let us know your detailed requirements. We will get back to you with our offer and HDPE price quote

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Fortunately fort he environment and manufacturers seeking low cost sources of HDPE, HDPE is a highly recyclable material, which when handled correctly can be recycled several times before it begins to show any signs of breaking down. It has a very strong molecular structure which can stand multiple transitions from the liquid to the solid phase without losing structural integrity.

The process by which HDPE regrind is made essentially a long cleaning process. Post consumer scrap HDPE contains all matter of contaminants from food scraps to metals to glass and even other plastics. Because the kerbside pickup recycling process from which the bulk of HDPE is reclaimed is inherently flawed, being carried out in its initial stages by private citizens, a great deal of effort must go into making sure the HDPE regrind is as close to being pure HDPE as is possible before it is on sold to manufacturers.

The first stage of turning reclaimed scrap HDPE into useful HDPE regrind is removing the large contaminants from the scrap HDPE. Typically, scrap HDPE will arrive at the recycler in large bales, which are then broken open. There are different types and grades of scrap HDPE bales. Some have been sorted and cleaned in advance, with labels and lids removed, others are sold as is, with contaminants, labels, and lids still intact.

Once the bales are broken up, the HDPE scrap is put onto a trommel. The trommel is a rotating device that shakes many of the larger contaminants free of the HDPE. Pieces of glass, stones, metals, and a great deal of dirt are removed via the trommel.

Once the bulk of the large contaminants have been removed, the HDPE scrap must be sorted to separate it from non HDPE plastics which are often mistakenly placed in the bale, and other similar foreign objects visible to the human eye.

When it has been ascertained that the HDPE scrap is now comprised almost entirely of HDPE plastic, and any remaining contaminants are too small to be simply picked out, the HDPE scrap is shredded, cut up into small pieces and subsequently cleaned. Chemical solutions, detergents, and high temperatures are all employed in order to clean up the HDPE. This stage is where many stubborn labels and adhesives are finally removed from the HDPE stream.

Float/sink technology is then used to separate HDPE from the dirt and other contaminants which have been released in the washing process. In the float/sink process the washed scrap HDPE is sent into a water tank. HDPE is lighter than water, so it floats, whereas many contaminants, such as small pieces of metal, glass, or rock are heavier than water, and sink to the bottom. The HDPE is then scooped off the top of the water and dried.

The dryer used to dry the shredded HDPE is a large industrial spin dryer which pumps hot air around the HDPE, drying it and making it ready for the final processing before sale.

The HDPE might be further cut up into smaller pieces and sold as HDPE regrind, or it may undergo melt processing to make HDPE pellets or granules. Melt processing involves melting the HDPE regrind down and passing it through a series of filters to remove the last of the contaminants before extruding the melted HDPE through a die and cutting it into pellets. HDPE which has undergone melt filtration is the cleanest form of scrap HDPE, however HDPE regrind is often used as a raw material in applications where very high levels of purity are not required.

HDPE Regrind Supplier

Please contact us through the below form and let us know your detailed requirements. We will get back to you with current HDPE regrind availability and price quote

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Recycled HDPE pellets are HDPE pellets made from reprocessing scrap HDPE. Recycled HDPE pellets are of a similar quality to virgin HDPE pellets in terms of chemical and physical integrity, though there are restrictions on scrap HDPE products being used to package foodstuffs. There is also some risk of contamination or structural weakness due to poor handling that should be kept in mind when looking for a reliable supplier of quality repro HDPE pellets.

The bulk of scrap HDPE comes in the form of post consumer HDPE. Post consumer HDPE products are those HDPE products which have been manufactured for use in consumer applications, such as milk bottles, shampoo bottles, and other kinds of household receptacles. These products are used for their intended purpose, then reclaimed from recycling programs. Other scrap HDPE is reclaimed from industrial sources, coming in the form of plastic drums, or off cuts and rejected malformed HDPE products from consumer production lines.

As a result of the various sources of scrap HDPE, the quality and appearance of various types of recycled HDPE pellets is also varied. Some recycled HDPE pellets may be clear and translucent in color, originating from well sorted post consumer HDPE scrap. In other cases, the recycled HDPE pellets may have a raw grey color, or dye may be added to the mix to create a homogeneous coloration. It should be noted that color alone does not reflect grade or quality of recycled HDPE pellets, though translucent recycled HDPE is generally regarded as being a safer bet, and lends itself better to applications where asthetics are important.

Producing Recycled HDPE Pellets

Recycled HDPE pellets start life as HDPE scrap. The scrap must be washed and sorted, then shredded and washed again. Various processes are then undertaken to ensure that the shredded HDPE is clear of the bulk of contaminants such as dirt, metals, and foreign plastics. This is the first part of perhaps the most important stage of HDPE recycling, as contamination can make a batch of HDPE effectively useless.

Shredded HDPE, or HDPE regrind as it is sometimes known, is then sent into a heating and extrusion chamber. This is a long barrel shaped device with a screw running down the length of it. The barrel is heated, and as the HDPE is carried through the chamber by the screw, it melts down into liquid HDPE.

Filters contained in the chamber catch any remnants of contaminants in a process called melt filtration. Good melt filtration is essential to the production of high quality recycled HDPE pellets. Though the bulk of contaminants are removed prior to melting, the smallest contaminant particles inevitably pass through the initial cleaning and filtering stages, and are only removed during the melt filtration process.

Due to its molecular structure, if heated to the correct temperature, HDPE can be melted down and reformed into new products many times with negligible loss of structural integrity, however the melting process must be carefully monitored to ensure that the HDPE stays within the correct temperature range so that it does not solidify prematurely, or become overheated and start to break down.

At the end of the chamber is a die through which the liquid HDPE is extruded. A blade slices the tubes of liquid HDPE into pellets, which are then cooled. This can be achieved by either extruding the pellets under water, or having the pellets drop into a water bath, occasionally circulated air is used to cool the pellets, but this is generally a slow and cost ineffective practice.

Grades of Repro HDPE Pellets

Recycled HDPE pellets come in all grades. It is possible to purchase injection molding grade recycled HDPE pellets, blow molding grade recycled HDPE pellets, pipe grade HDPE pellets, the list goes on.

When ‘grades’ are referred to, what is really being spoken about is the MFI, or Melt Flow Index. Melt flow index is a measure of how viscous HDPE is when melted, and is related to the molecular density of the HDPE. Very dense HDPE has a low MFI, and becomes thick and slow flowing when melted. This type of HDPE is suitable for blow molding applications. Conversely, HDPE with a high MFI becomes very runny when melted, and is more suitable for applications such as injection molding.

Repro HDPE Suppliers

We source reprocessed HDPE pellets from several suppliers world wide. Let us know your detailed requirements and we will get back to you with current offers and HDPE price quote

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However, in many cases, scrap HDPE is still underutilized in manufacturing today. Ideally scrap HDPE could be used for the manufacturing of almost all products besides those which come in contact with foodstuffs. Scrap HDPE has been declared unfit as a material for packaging which contains foodstuffs as a result of the perceived risk of contamination that could possibly have taken place during the life of the HDPE prior to being recycled.

So then, why is scrap HDPE not being used in more applications? The problem is not the processing of scrap HDPE, or the willingness of manufacturers to use it in their products, rather it is access to the scrap HDPE itself. Many businesses make use of post industrial scrap HDPE, which largely comes in the form of offcuts from the manufacturing operations of other companies. However, the largest potential source of scrap HDPE is post consumer scrap HDPE, that is, HDPE products such as milk bottles, shampoo and conditioner bottles, whipped topping tubs, the list goes on. Many thousand tonnes of HDPE products are newly produced per year, however not nearly enough of them are making it back into the recycling programs that could turn HDPE refuse into new HDPE products.

It is not only traditional manufacturers who seek to use scrap HDPE in their products either. Environmentalists, and green companies are also turning to scrap HDPE as a source of raw material. Recycling HDPE products, especially post consumer products such as shampoo bottles, detergent bottles, fabric softener bottles, and milk bottles saves tonnes of landfill space every year. It is still lamentably true however, that much of the HDPE products produced in North America will not be turned over for recycling, and will find their way into landfills, exacerbating the environmental problems that the USA, much like many other countries, faces on a day to day basis.

Recycling education programs have been in place since the 90’s, and since that time there has been a steady increase in the volume of recycled material that is collected from consumers. There are still some areas of confusion however, as over the years demands for various types of plastics increase, and plastics that were once deemed unrecyclable become recyclable, keeping the consumer informed and motivated to set their discarded HDPE products out for recycling is an important concern for all members of the supply chain.

An additional problem facing the scrap HDPE market is collection. Efficient recycling programs are in place in many urban environments, but there are still swathes of the country where there are few recycling facilities, and no kerbside collection services. Consumers can hardly be expected to make special trips to recycle their plastics, so it is vital that local government bodies take the lead when it comes to setting up programs for the collection of plastics.

If local government will not step up to the recycling plate, there is an opportunity for private enterprise to provide consumers with bins for their plastics, and scheduling a weekly pick up. For this outlay, a private enterprise can reasonably expect to make a sizable profit on plastics which are discarded and can be collected for simply the cost of collection, and can then be on sold at a profit as either baled scrap HDPE, or processed into scrap HDPE flake or regrind.
Post consumer scrap HDPE is perhaps the ideal recycling model, and an answer to not only the problems of environmentalists, but also of consumers and manufacturers alike. Making use of post consumer HDPE protects the environment, cuts costs for the manufacturer, and can also save the consumer money in the long run, as manufacturers are able to price their products at a lower rate due to the savings they have made by using post consumer scrap HDPE.

Post Consumer Scrap HDPE Prices

To get a list of currently available post consumer HDPE Scrap supply and prices please contact us by using the below form

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HDPE Use:
In HDPE Film form it is used for snack food packaging and cereal box liners. In blow molded HDPE form it is used for non carbonated drink bottles. In injection molded form, it is mostly used for margarine tubs, deli food and whipped toppings. High Density Polyethylene is also used as detergent bottles, milk jugs, garbage containers, water pipes (plumbing) as well as packaging for industrial chemicals such as detergents, bleach and acids.

General uses of HDPE include bread trays, films for grocery sacks, bottles for beverages and household chemicals and injection-molded beverage cases.

Scrap HDPE:
In essence Scrap HDPE is recyclable waste consisting of only High Density Polyethylene. It comes all sorts of shapes, forms and colors. The better it is sorted and cleaned, the more it is worth on the recycle market. Some popular forms of HDPE Scrap are:

• postconsumer HDPE Scrap (A finished HDPE material that would normally be discarded as a solid waste after having completed its life cycle as a consumer item)
• HDPE film trimmings (scrap from carrier)
• HDPE bags (carrier bags made of HDPE. They come in colors: natural, white, mixed, printed and unprinted)
• HDPE Regrind (HDPE carrying bags and similar, converted into hard solid structure then grinded and made ready for recycling)
• Scrap HDPE bottles
• HDPE barrels and drums (also named HDPE canes, HDPE tanks. Those are empty “barrels” made of HDPE. They can be squashed and mounted on palletes or in original form – which is unpractical.)
• HDPE mixed postconsumer scrap (includes everything and anything made of High Density Polyethylene. HDPE mixed post consumer scrap can be sorted by color)

HDPE Scrap forms:
High Density PolyEthylene Scrap comes in various forms. It can be baled, loose, compacted into secure bundles (cubicles), rolls, grinded into flakes, etc.

Scrap HDPE prices:
To get the current price list of Scrap HDPE and available options, please fill out the contact form on the bottom of this page.

HDPE Scrap Suppliers:
Please fill out the contact form below and we will send you a list of currently available suppliers.

Glossary, HDPE

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HDPE:
It is an abbreviation for High Density Poly Ethylene.

Post Consumer Regrind (PCR):
PCR is post consumer plastic products that have been recycled, this means they are ground down to be re-used in manufacturing of new products made of the material in question. Level of grinding can be between 25-100%.

HDPE post consumer regrind is recycled High Density Poly Ethylene cut into small pieces. The HDPE regrind can be sorted by color or mixed. HDPE plastic regrind made by HDPE processors should be ideally loaded directly into a wash system and processed completely into a finished product.

If the HDPE regrind has to be stored, it should be ground directly into and stored in gaylords. Gaylords are extra heavy duty boxes that are mounted on pallets for shipping loose items. They have about one cubic yard in volume and are capable of holding HDPE flakes in the range of 600-1000 pounds. The gaylords should be fastened on shipping pallets to maintain their integrity during handling, storage, and transport.

HDPE regrind use:
Generally natural HDPE regrind is used in high value end-use applications (such as clear, blown film). It requires higher quality especially with regard to injection-molded HDPE, Polypropylene, and color contamination. The quality requirements for HDPE regrind are normally more demanding than for baled HDPE.

Where to Buy or Sell HDPE Regrind:
Should you need information on where to buy or sell HDPE Regrind please use this contact form below and we will reply as soon as possible.

Glossary, HDPE

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