1. Recycled low-density polyethylene (LDPE) process
LDPE, the scientific name for high-pressure polyethylene, is generally referred to as plastic packaging film. Such as woven bag liner film, food packaging film, daily necessities packaging film, greenhouse film. Most of these films are natural colors, there are also light blue, black, it is best to separate the color samples before recycling. You can't put the low-pressure film, PP film together, let alone OPP and PVC film. The recycling and reuse of LDPE is the recycled LDPE process.
The whole recycled LDPE process has four main processes.
(1) Crushing process. Crushing and rinsing with water is more effective. Some good high-pressure films if kept clean enough, without adding new material can be re-blown film. So in the crushing process to pay attention to cleaning, when the crushed material flows to the water tank is best to roll again, the purpose of further rinsing the clean point.
(2) Drying process. Generally to the dumping machine to dump the residual water, such as conditions for sun drying, which can save electricity and improve quality, of course, to pay attention to prevent secondary pollution of the material in the sun drying.
(3) Granulation process. The pellets made by the special extruder have two basic uses: blowing film again and injection molding. The material coming out of the 60 to 80 mesh filter can be blown again; the material coming out of the 40 to 60 mesh filter can meet the quality requirements of injection molding. Generally speaking, high-pressure material is blown film again, good blowing native color poorer blowing black film and garbage bags, do injection plastic after the price is lower.
(4) cutting granulation process, generally cold water cutting granules. This process must pay attention to the packaging to distinguish the label. One for blow molding, one for injection molding to avoid mistakes. In addition, the bags for blow molding must be outside the bag with a liner bag to avoid secondary pollution.
2. Recycled polypropylene (PP) process
PP mostly from daily necessities more, plastic boxes, foot basins, buckets, rice baskets, plastic chairs, stools, woven bags, and other packaging has woven fabric, packing tape, etc.
(1) First of all, separate the colors of various materials, because the separation will make it convenient for users and the price can be high.
(2) Crushed and rinsed with water, to the shaking machine to shake off the remaining water, and then sun-dried and bagged. Mix with a mixer and add some color and additives.
(3) Special plastic machine for onboard granulation, but the granulation temperature must not be too high, easy to brittle, so be sure to pay attention to the temperature.
(4) Water-cooled cutting pellets, to standard 3X4mm, otherwise the appearance of the good material out again is not good, not standard.
3. Recycled polyethylene terephthalate (PET) process
PET, scientific name: polyethylene terephthalate, is a linear thermoplastic.
PET is usually crystalline plastic. PET bottles have replaced some traditional packaging materials and are used in a large number of food, beverage, and cosmetic applications due to their lightweight, lack of fragility, and low energy consumption. The recycling of PET and its reuse is the recycled PET process.
The recycling process of PET bottle flakes is to separate the PET bottle body from the cap, label, etc., and then crush, clean and dry.
Its specific process is as follows.
(1) First is the selection process: various PET bottle flakes are selected and sorted into different categories. Tear off the outside of the trademark, most of these trademarks are OPP, but also part of the polychlorinated ethylene shrink film must first peel off.
(2) Powdering process, rinsing with water during the crushing process to get rid of the dirt in the various PET bottle flakes.
(3) Put these flakes into the steam treatment unit and add caustic soda to remove grease and other stubborn impurities.
(4) Wash them with water, shake off the remaining water and bag them. Then go to the vacuum oven for drying.
(5) Spray silk, set, stretch with hot water steam transfer, and set again.
4. ABS plastic process flow
ABS plastic, most come from electrical products, a variety of daily necessities, and some small parts on machinery.
(1) ABS for more, computer cases, TV cases, instrument cases, car panels, decorative materials, pick this material apart, especially electroplating, painting colors, etc. to be separated.
(2) Chemical treatment, de-plating, de-painting, but de-plating and de-painting must be careful, because the chemical potion has a certain ratio, to use protective supplies and containers, otherwise, it will cause injury and other events.
(3) Cleaning tank to go to clean, then go to dry, color matching or put auxiliary materials, the purpose is to improve the quality.
(4) Special extruder goes to granulation but must be put on the filter, but the filter is put according to the product requirements.
5. Recycled polycarbonate (PC) process
Polycarbonate, non-crystalline plastic, engineering plastic class. Mostly from textile accessories, automobile headlights, taillights, turn signals, candy-making molds, discs, telecommunications equipment, photographic equipment, etc.
(1) First of all, the acquisition to PC selection, there are transparent opaque, blue, red, green, black must be separated; also modified, such as textile accessories are mostly modified; such as discs, lamp heads are coated.
(2) Cleaning of various colors of PC, and discs and lamp heads, such as decorating process, also operates with the same principle as ABS. Then sun-dried, after categorization, sent to the extruder production.
(3) PC some more yellow, you can produce porcelain white; transparent still produce transparent; other colors can add coloring agents and material additives.
(4) Special extruder pelletizing, but PC itself is easy to age so can not be repeatedly back to the material, pelletizing must be careful, cut grain packaging.
6. Recycled polyvinyl chloride (PVC) hard material process
Most PVC hard materials come from construction materials, plastic steel windows, and doors, plating hard plates, plastic valves for chemical plants, downpipes, and decorative materials.
(1) First of all, the selection process separates each color. These materials are largely divided into white, gray, and black, but do not mix PP and PE.
(2) To the crusher crush, but also with water crush. Remove the pollution with water to clean, and then sun-dry to prevent secondary pollution.
(3) On the mixer for ingredients, mixing. If it is white material then add some coloring agent, according to the need to put additives, etc.
(4) Special PVC extruder for scraping granules, cooling and bagging labeling factory.
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