First, the regeneration of low-density polyethylene process
LDPE, scientific name of high-pressure polyethylene, it generally refers to plastic packaging film. Such as: woven bag liner film, food packaging film, daily necessities packaging film, greenhouse film. Most of these films are natural, there are light blue, black, in recycling Before the best separation of color samples. Can not put the low-pressure film, PP film together, but can not put the OPP and PVC film into. The recovery of LDPE and reuse it, is the regeneration of LDPE process.
The entire recycled LDPE process has four main processes:
1. The crushing process is better with water rinsing and rinsing. As some good HV membranes are kept clean enough, the membrane can be blown again without adding new materials. Therefore, during the comminution process, cleanliness should be taken care of. After the sink is best to roll again, the purpose of further rinse the cleaning point.
2. Drying process. Generally, it is necessary to dry the remainder of the water in the dryer and dry it if possible. This saves electricity and improves quality. Of course, it is necessary to prevent secondary pollution of the material during drying.
3. Granulation process. Granules produced by special extruders, have two basic uses: Re-blow film and injection molding. Material from 60 to 80 mesh filter can be blown again; at 40 to 60 mesh The material coming out of the filter can meet the quality requirements of the injection molding. In general, the high-pressure material blows the film again, and the good blowing color is almost blown black film and garbage bag, and the price after injection molding is lower.
4. The pelletizing process is generally cold water pelletizing. This procedure must be noted when the packaging is labeled. A blow molding, an injection molding, to avoid mistakes. In addition, the packaging bags for blow molding must be outside the bag plus Lining bag to avoid secondary pollution.
Second, renewable polypropylene (PP) process
Most of the PP comes from daily necessities, plastic boxes, basins, buckets, rice scouring, plastic chairs, stools, woven bags and other packaging woven fabrics, packing tapes, etc.
1. First of all, separate the colors of various materials, because the separation will make the user convenient and the price can be high.
2. With water, smash and rinse, then spin off the remaining water in the dryer, and then carry out drying and bagging. Mix with a mixer and add some color and additives.
3. The special plastic machine is used for granulating on the car, but the pelletizing temperature is not too high and it is easy to make it brittle, so be sure to pay attention to the temperature.
4. Water-cooling pellets, to standard 3X4mm, otherwise the appearance of good material does not look good, not standard.
Third, recycled polyethylene terephthalate (PET) process
PET, scientific name: polyethylene terephthalate, it is a linear thermoplastic.
PET is usually a crystalline plastic. PET bottles are lightweight, not easily broken, and have low energy consumption. They replace some traditional packaging materials and are widely used in food, beverage, cosmetics, etc. PET recycling and Reuse, is the regeneration PET process.
The recycling process of PET bottles is to separate the PET bottles from the lids, labels, etc., then crush them, clean them, and dry them.
Its concrete process is as follows:
1. The first is the selection process: The various PET bottles are picked and categorized. Tear off the outside of the trademark, most of these trademarks are OPP, there are also some PVC shrink film, must first be stripped.
2. Flours process, rinse with water during crushing to remove dirt from various PET bottles.
3. Put these pieces into a steam treatment unit and add caustic soda to remove greasy and other stubborn impurities.
4. Wash with clean water, dry the remaining moisture and bag. Then dry in a vacuum oven.
5. Spinning, setting, hot water vapor transfer, re-setting.
Fourth, ABS plastic process
ABS plastics, most of them come from electrical products, a variety of daily necessities and some mechanical components.
1. ABS is more for the computer shell, TV shell, instrument shell, car panel, decorative materials, pick this material, special plating, paint color, etc. to be separated.
2. Chemical treatment, withdrawal, paint back, but the withdrawal of the paint must be careful, due to a certain ratio of chemical medicine, use protective equipment and containers, otherwise it will cause injuries and other events.
3. Clean the tank to clean it, then dry it, match colors or put auxiliary materials. The purpose is to improve the quality.
4.Special extruder to granulate, but must put the filter, but the filter is placed according to product requirements.
V. Recycled Polycarbonate (PC) Process
Polycarbonate, amorphous plastics, engineering plastics, etc. Mostly come from textile accessories, car headlights, taillights, turn signals, candy making molds, discs, telecommunications equipment, camera equipment, etc.
1. First of all, the acquisition of PC to choose, there is transparent opaque, blue, red, green, black must be separated; also modified, such as textile accessories are mostly modified; such as discs, lamp caps are coated.
2. Cleaning the various PCs, and the disc platen capping process, also operate with the same principle as ABS. Then dried, after classified, send extruder production.
3. Some PCs are relatively yellow and can produce porcelain white; transparent still produce transparent; other colors can add colorants and material additives.
4.Special extruder granulation, but the PC itself is easy to aging so it can't be fed back several times, Granulation must be careful, Pellet packing.
VI. Recycled Polyvinyl Chloride (PVC) Hard Material Process Flow
Most PVC hard materials come from building materials, plastic steel windows, hard plated plates, plastic valves used in chemical plants, sewage pipes, and decorative materials.
1. First select the process and separate each color. These materials are divided into three types: white, gray and black. Do not mix PP and PE.
2. To the crusher, but also with water crushing. Remove the contamination with water and then dry it to prevent secondary pollution.
3. Mix on the mixing machine and mix. If it is a white material, add a coloring agent, and add additives as required.
4. Dedicated PVC extruder for scraping, cooling bagging factory.