The global economy is booming, the demand for consumer goods is strong, the sales of communication equipment and cars soar, and the supply of plastic raw materials is in great shortage
in 2004, the sharp rise in the global price of plastic raw materials surprised the industry that an unnoticed market - the waste recycled plastic market turned out to be promising. As the price of new plastics rises too fast, the demand for recycled plastics also increases greatly, and the price also soars. In China, for example, waste plastics are far from meeting the market and still need to be imported in large quantities. It is estimated that in 2004, China imported about 4million tons of waste recycled plastics. In that year, the price of waste plastics rose from 2000 ~ 3500 yuan/ton to 4000 ~ 8000 yuan/ton, an increase of more than 50%, almost equivalent to the price of new materials at the beginning of the year. In China, the quality requirements of many plastic products are not high, so some processing enterprises will use recycled materials as much as possible. Industry insiders have realized that there is also a lot of room for the development of waste plastic recycling industry, which is an industry worthy of attention and investment
recycled plastic products seen in daily life include: building materials (such as steel, sheds and wall panels), gardening materials (such as flower pots and garden piles), containers for agricultural products (such as containers for eggs, fruits and vegetables), office supplies (such as loose leaf binders and covers), non food containers and reusable packaging boxes, entertainment facilities, outdoor furniture and other plastic products
in recent years, there has been a special technology to study the production of fuel oil from waste plastics. Because plastics are polymer compounds polymerized by C and h in crude oil, that is, polymer compounds polymerized by C and H are the main components of plastics. It is completely feasible to melt and decompose plastics into oil through new processes. The current research focus is how to achieve cost-effectiveness
crude steel capacity utilization rate reaches 87%, and the recovery cost is relatively low.
industry insiders estimate that in 2005, the consumption of waste plastics continued to grow and reached another peak. Due to the treatment of waste plastics, the general processing technology content and equipment requirements are relatively low, the sources are everywhere, the production cost is not high, and the profit is still considerable under the current price level. However, it is difficult for general large enterprises to adopt large-scale monopoly, which is very conducive to the growth and development of small enterprises
according to incomplete domestic statistics, the recovery rate of plastic products in China is less than 10%. On the other hand, the actual recovery rate is less than 1%. Judging from the figures, it is self-evident that there is a huge waste plastic market and development space in China
in other words, recycling waste plastics is a work that benefits the country and the people. The coordinated development of plastic processing industry and environmental protection is an important topic for the sustainable development of plastic processing industry. DOE optimization warpage based on Moldflow cloud computing
in recent years, China's plastic industry has developed rapidly and has become an important pillar of the national economy. Due to the serious shortage of raw material resources in China, people have almost spontaneously brought the utilization of renewable resources to the extreme. In the process of establishing a recyclable and economical economic development model, the important value of plastic recycling is also being highly valued by national departments, Understanding the use of renewable resources is of great significance to alleviate the shortage of domestic resources and energy
it is reported that the leaders in charge of national economic development are planning, organizing cross departmental joint drafting of preferential policies, special laws and regulations, determining the management responsibility system, and establishing the market system and business order to guide and supervise the healthy development of the recycling industry
among them, the national development and Reform Commission is studying and formulating a number of special regulations to support resource recycling,? Zhang Bang likes to steal Kun from a fat tree? At the same time, we are comprehensively evaluating the first batch of national circular economy pilot projects, and actively promoting the second batch of national pilot projects to support renewable resources projects with national debt
the Ministry of Commerce will also determine a unified management division of labor responsibility system, and organize the establishment of renewable operator qualification system and market access system; Improve tax policies and reduce the burden on recycling enterprises; Reasonable layout of recycling points; Establish a statistical system for the recycling industry, grasp the situation of the industry, and take various measures to maintain the business order of the recycling industry of waste materials such as waste plastics
the State Administration of quality supervision and its relevant departments are also formulating relevant standard systems, mainly including comprehensive foundation and management standards for waste products and waste recycling and reuse, recycling methods, processes, and equipment standards, in accordance with the "2005-2007 development plan for resource conservation and comprehensive utilization standards", in order to ensure that plastics will not be subject to secondary pollution in recycling, recycling, utilization, import and other links, Disassembly and reuse methods, processes, equipment standards, as well as the basic standards, management and technical standards of used goods circulation
although the waste plastics recycling and recycled plastics industry has great economic value, it also brings a number of health care and environmental maintenance problems in the process of processing or importing waste plastics
at the beginning of 2004, a case of waste plastics in violation of the Basel Convention and China's environmental protection and control standards occurred in Shandong. To this end, the General Administration of quality supervision, inspection and Quarantine of the people's Republic of China (AQSIQ) issued announcement No. 47 in 2004, suspending the import of national waste plastics and relevant inspection and quarantine procedures involved in the case. After mediation by many parties, the incident was resolved only after the waste plastic manufacturer involved promised to take improvement measures
engaging in waste plastic recycling and processing will bring negative effects, the most common of which is water pollution and damage to the sanitary environment
water pollution caused by recycled plastics industry is mainly due to the mixing of various substances attached to waste plastics in the water during the crushing and cleaning process
different types and sources of waste plastics lead to different degrees of pollution, mainly including the following:
pollution of waste plastics
1 Color pollution: waste plastics have been contacted or packaged with dyes and pigments, etc.
2 PH pollution: waste plastics contact or package too strong acid and strong alkaline substances
3 Microbial pollution: waste plastic comes from disposable medical equipment
4 Toxic substance pollution: waste plastics have been exposed to or packaged with toxic and harmful substances
5 Grease pollution: waste plastic has contacted or packed grease substances
6 Solute pollution: contact with waste plastics or package sodium chloride, soda ash, etc.
7 Suspended solids pollution: waste plastics contact or package cotton yarn, chemical fiber, quartz sand, cement, calcium carbonate, etc.
8 Organic pollution: waste plastics have been exposed to or packaged with grain, feed, beverages, etc.
among the above eight pollution categories, waste plastics of categories 1 to 4 generally contain toxic and harmful substances, so it is recommended that small enterprises not purchase and process them, Because this kind of waste plastic needs to be equipped with perfect water treatment facilities and do a good job of workers' labor protection. Everyone is looking for a zigzag experimental machine. The appropriate amount of refrigeration materials should be able to cover the air-conditioning evaporator and the air-conditioning copper pipe (otherwise, it is easy to frost on the evaporator of the air conditioner, so as to avoid injury to human body after contact!
waste plastics of categories 5 to 8 do not contain toxic or harmful substances, and can be discharged after simple treatment, so they are more suitable for processing and treatment of small enterprises.
in order to facilitate the recycling of waste plastics, enterprise product designers in advanced countries have consciously avoided the use of a variety of plastics.
processing difficulty is not high
more common waste materials Recycling technology can be divided into mechanical recycling, chemical recycling and raw material recycling
1. The mechanical recovery method
is to directly recover the discarded materials and make them into plastic particles, and then send the reconstituted rubber particles back to the plastic manufacturing process to make new products. The first is to collect discarded plastic waste from various ways. Including water bottles, detergent bottles and other household waste, and then sent to the material recycling center together. The waste is separated from other materials by machinery or hands, and then all kinds of mixed plastic waste are sorted out, sorted and packaged and sent to the plastic recycling plant
after receiving the designated plastic bales, the reconstitutor will send these materials to the bag crusher for breaking up, and then send them to the special vibrating screen. Fine garbage and dust will fall into the garbage bag through the sieve. This is the first step to remove impurities. After that, the screened recyclable plastic will enter the grinding and cleaning process. Then cut the material into fine pieces to make the label and other attachments fall off. After shredding, add water to soften the fragments and remove impurities, and then send the fragments to the cleaning machine. Some cleaning machines use warm water and detergent; Others use room temperature water, which is heated by mechanical movement during cleaning. This cleaning process can remove residues, dust particles and labels. Then, the flotation cylinder is used to separate the plastics with different densities from the impurities. Dust particles and dense plastics (such as PET) settle at the bottom of the cylinder and are removed later. Clean debris floating out after separation shall be dried with hot air, and then the film and label shall be separated by air flow sorter. After the plastic fragments enter the sorter, an air flow is blown downward, and the lighter film fragments will be blown away, while the heavier plastic fragments will continue to sink. Finally, plastic fragments are melted, filtered, and then extruded into small particles. At the beginning, the plastic fragments are poured into the big bag for mixing to reduce the quality difference, and then the fragments are sent to the extruder. Inside the machine is a heated cylinder with a screw conveyor. After melting in the extruder, the debris flows through the filtration at the end of the machine. Non molten impurity particles cannot pass through the eyes, while pure Molten Substances squeeze through the plate full of holes and become noodles. During the cooling period of these plastic strips, they can be cut quickly to make small particles
it is reported that Austria has launched a machine to automatically screen waste plastic bottles, which can distinguish eight kinds of materials, such as pet, PVC, PE, PP, PS, PA, ABS, etc. No matter whether the plastic bottle is labeled or deformed, it can sort and recycle plastic bottles at a rate of 5 to 7 per second. This product can simplify the picking process
2. Chemical recycling
refers to the removal of polycondensation or addition polymerization by depolymerization to make the polymer return to monomer. Plastics that can be regenerated by this method include polyester (for example, Qi 1 is pet plastic for water bottles that incorporate Sinopec Maozhan base into the national petrochemical industry base plan), polyamide (such as nylon for carpet), and polyurethane (such as foam plastic for car seats). For long-chain polymers, chemical methods and heat can be used to break the chain
if the purpose of depolymerization is to reduce the chemical components of the original polymer, this process is called raw material manufacturing or monomer manufacturing
pet, some polyamides and polyurethane can be effectively depolymerized, and the synthetic chemicals produced can be used to manufacture new plastics, which is no different from the original polymers
3. Raw material recycling
although this process includes chemical recycling, it is interpreted in a narrow sense that polyolefins and polyolefins are depolymerized by heat to turn them into various smaller olefin intermediates. This kind of intermediate is not very different from gasoline or lubricating oil. In some cases, heat can be used to depolymerize the addition polymer and directly change it back to monomer. The recovery rate of this process is quite high, such as converting polystyrene to styrene and polymethylmethacrylate to methyl methacrylate
depolymerization of recycled monomer raw materials