Recycling can be used to treat the problem

In the 1980s, people were also pleasantly surprised by the fact that disposable foam plastic tableware (hereinafter referred to as “foaming tableware”) brought convenience, hygiene, and quickness to a fast-paced life. However, in the 1990s, it caused “white pollution” to the environment. "And headaches. In November last year, the State Economic and Trade Commission used grounds of “lagging behind” and “serious environmental pollution” as a reason to eliminate obsolete tableware in 2000. This move has led to controversy over the past decade of governance "white pollution" approach, however, many industry insiders and experts are still skeptical and worried about this move: elimination is the best way to manage "white pollution"?

First, foaming utensils is really backward products?

The production of foamed tableware was mostly developed in the late 1980s and early 1990s in China. At present, China has more than 130 production lines, its production processes and equipment are mainly introduced in Japan and Taiwan, and the degree of automation of production is quite high. At present, the nation's foaming tableware industry only introduces one item of equipment, which has invested more than 80 million U.S. dollars in foreign exchange, and has a production capacity of 15 billion per year, which can fully meet the current market of 80-100 billion per year. The raw material for the production of such utensils is polystyrene (PS) obtained from refining or fractionation of petroleum or coal processing. PS packaging materials are only consumed in 1% of the country's natural oil (according to US data), and can also be recycled. Reuse. In recent years, in the manufacture of PS foam packaging materials, Freons that destroy the atmospheric ozone layer (CFCS) are no longer used, but instead hydrocarbons (such as butane and pentane) are used as foaming agents, thereby realizing the entire production process. The basic century has no pollution to the environment. Moreover, the low energy consumption and low waste of the three wastes in the production process are also superior to other materials. For example: According to the survey data of the American Plastics Industry Association (SPI), the energy consumption for producing 1m3 of plastic is 1.486×108kJ, while that of 1m3 is 3.6×108kJ, that of copper is 5.9×108kJ, and that of aluminum is 7.4×108kJ, according to a research institute in the United States. (Widwest Research Institute) comparison of research data on the production and environmental impact of producing 1 million different paper and plastic products. The production of the same specifications of the product, the energy consumption and quality of the paper is 3-5 times that of plastic, CO2 released during the process And nitrogen oxides are much higher than plastics.

In addition, disposable foam plastic tableware also has superiority that many other materials cannot match: hygiene, safety, moisture resistance, insulation, water (oil), seepage prevention, robustness, economy, and more.

Furthermore, the foamed tableware itself is a non-toxic and harmless product. The visual pollution and potential pollution caused by it are completely caused by people’s uncivilized behavior—disregarding and lacking of a scientific management system. Neglect the superiority of bubble dishes, and it is even more difficult to simply eliminate things. We should scientifically recognize its role in the development of the national economy and adopt the product life cycle assessment method (LCA) to comprehensively analyze its impact on resources, energy, and the environment before we can obtain a comprehensive and objective macro decision-making on the product.

Second, the pros and cons of other green tableware

At present, there are three types of meals under the banner of “environmental protection” and “white pollution”: one is pulp molding or cardboard stamping tableware; the second is chaff and rice straw smashing and molding tableware; and the third is degradable plastic. tableware. Throughout the above environmental protection tableware, the common advantage is to emphasize the degradable, vegetable fiber tableware can be recycled. However, the degree of degradation is not as ideal as one might think. Disposing or not burying it will take months or even half a year to start moldy decay and fragmentation, and starch-laden degradable plastics can only be reduced at best. Capacity reduction 20-30%, and can not be completely degraded.

In terms of performance, although the above three types of tableware can be grease-proof, waterproof, and heat-resistant, the strength and stiffness are not as good as those of foam tableware. Moreover, the cost is higher than that of foamed tableware, and there are also defects in mold prevention. In the production process, although the pulp molding process is relatively mature, the “black” and “white” wastewater generated in the production process cannot be neglected; the cardboard stamping and the process are simple, but the special kitchen board is still in the development stage and has not been industrialized. . All types of degradable plastics are in the research and development stage in China, and only the starch filling type is more mature. However, there are also problems in improving the starch ratio, whiteness, and mechanical properties in the production process. The appearance, weight, and toughness of the shell-type tableware are all greatly deficient.

Through the above analysis, it can be concluded that the above environmental protection tableware is superior to the foam tableware in terms of degradation performance, but its overall performance (especially insulation moisture resistance), especially in terms of price, is difficult to fight with foamed tableware. Therefore, even though the Guangzhou Municipal Government issued a notice prohibiting the use of foamed plastic tableware as early as September 1997, today, foaming tableware is still popular. According to investigations by relevant departments, all kinds of green environmental protection tableware still account for less than half of the market share. This is of course due to insufficient publicity and inadequate law enforcement. However, it also considers that the laws of the market economy are working.

Third, foaming tableware and waste polystyrene (PS) reuse technology

In addition to foaming tableware, packaging materials made of expanded polystyrene, cushions made of polystyrene, soap trays, instrument housings, decorations and lighting fixtures, etc., are used for daily commodities, electronic industries, and light industrial products. The waste is also a factor that causes environmental pollution. According to the inspection data of the relevant departments in Guangzhou, the waste plastic products in Guangzhou have accounted for 11% of the waste, and the amount of wastes per day is up to 400 tons or more. This plastic material, which was widely developed at the end of the 19th century, has been widely used as the main basic material for today's technology and civilization. At the same time, it is inconceivable that its waste has not been rotted and decomposed and caused environmental pollution. In fact, plastics are produced with limited resources (petroleum, coal) on the earth, and they should be properly cherished. Discarded plastic is a valuable resource. There are many ways to reuse it, and there are many kinds of recycled products. There are also many successful examples of the research and development of waste plastic recycling at home and abroad. The following is a brief introduction to the reuse of waste polystyrene foam (EPS) and waste polystyrene (PS).

In general, foamed PS products have two major recovery pathways: physical recovery and chemical recovery. One of the methods of physical recycling is to use humicifiers or packaging buffers after smashing. Second, heat and melt them and process them into recycled pellets. Further, they are made into recycled products such as stationery, furniture, and imitation wood building materials. In this regard, Beijing Green Green Plastic Recycling Co., Ltd. is a successful example. The company's monthly processing of EPS amounts to 150-180 tons, and it can completely dispose of the lunch boxes recovered in Beijing to produce better-quality recycled particles as raw materials for various stationery and office supplies. The output rate has reached 70%.

Chemical recovery is mainly defoaming, depolymerization and cracking. For example, the waste EPS can be recovered by defoaming thermal cracking of toluene and other organic solvents, and the styrene monomer can be recovered. The waste PS can be mixed with other waste plastics to catalyze and crack. It can produce gasoline, kerosene, diesel and other fuels. According to a recent "Guangzhou Daily" report, the Guangzhou Institute of Sanitation collaborated with other research and production departments to produce gasoline and other fuels from waste plastics in the suburbs of Guangzhou.

In addition, the waste lunch boxes can be dissolved to produce varnish and color paint. According to preliminary estimates of relevant professionals, according to the calculation of consumption of 800,000 foamed lunch boxes on the 1st in Guangzhou, all recovered can produce 35-40t paint. The production process is not complicated, the equipment is not much, and the investment is not big (less than one million yuan). Therefore, the rough calculations (not including recycling collection fees) have some economic benefits. What's more important is the elimination of white pollution. What are the obvious benefits of environmental protection?

Can also be dissolved modified method (such as formaldehyde) will be made of waste EPS finishes and adhesives; polyvinyl alcohol and other mixed solvents will dissolve waste EPS modified strong adhesive doors and windows sealant.

There are also organic compounds that are thermally decomposed by PS waste under reduced pressure conditions to obtain plastic plasticizers.

In summary, the waste polystyrene can be depolymerized or cracked at a certain temperature, pressure and catalyst conditions, and various organic compounds and monomers can be recovered.

In addition, the foamed PS can also recover heat energy, because PS is mainly derived from oil and natural gas, and thus can generate as much energy as heavy oil when it is burned, and the burned ash only accounts for 1% of the original volume.

The technical and economic evaluation shows that the collection cost of waste PS accounts for a considerable proportion in the cost of recycling and reprocessing, so the key to the economic benefit of recycling is the recovery price of waste PS. This, in turn, depends on whether or not an effective recycling network can be established.

4. Recycling (recycling) is an important way to control environmental pollution

At present, the world's most advanced countries have listed the recycling of plastic packaging waste as the focus of environmental protection work. They have steadily increased their recycling goals by establishing relevant organizational structures, formulating relevant departmental regulations, setting up recycling procedures, and establishing collection outlets.

For example, in the 1980s, the United States established the “Plastic Container Recycling Federation”, “Foam Packaging Recycling Coalition”, “PS Recycling Company”, and “Recycling Plastics Research Center”. In 1995, the PS recovery rate was increased to 25%. The U.S. Environmental Protection Agency promotes a more complete processing system that makes PS's processing system safe and effective. It includes: resource reduction, reuse, recycling, waste - energy conversion and landfill. In the United States, about 30% of the PS buffered packaging materials have been reused. In the postal service, the ratio of buffered packaging materials reused is as high as 50%. Due to the effectiveness of reuse, the demand for PS raw materials was reduced only in 1994. 22 million pounds.

It is worth mentioning that: in 1988, 21 states in the United States promulgated the provisions of 1332 to restrict and ban certain plastic products and plastic packaging. However, many changes have taken place after implementation, such as California, Oregon, Wisconsin, and Florida in the United States. The ban was changed after 1991 to require a certain recycling rate and recovery rate. Florida, USA, received a 1 cent prepayment for plastic bottle sales, which led to a 50% recovery of raw materials.

Japan is also a country where recycling has been done relatively well. Japanese foam PS producers have been collecting and recycling since the early 1970s. The Japan Foaming PS Product Recycling Association, established in May 1991, has contacted seven home appliance manufacturers to recycle Foam PS products, including the famous Sony, Sanyo and Toshiba companies. In Japan, there were 1,000 recycling bases in Japan and 300 commercial outlets were used for recycling. The recycling rate reached 31.2%. In addition, 20.3% of PS was used for heat recovery.

Recycled products include: hangers, video cassettes, ballpoint pens, rulers, toys, flower pots, chemical packaging, artificial wood, etc.

In 1989, some PS plastic related companies in Taiwan established the PS Foam Products Committee to carry out various preparations for recycling. In 1991, the “Green Keeping Foundation” was established to propose a “plan for the recovery and disposal of foamed plastic waste containers”; it organized a waste disposal company; dispatched personnel to Japan and the United States for inspections; and introduced the US’s recycling machines and incinerators. In 1992, a pilot recycling operation was conducted in Taipei. In the pelletizing and gas-electric cogeneration approach, the recycled EPS disposable tableware was disposed of, greatly improving its recycling rate. The recovery rate increased from 6.6% in 1992 to 1996. 56.98%. Finally, after the EPS disposable cutlery reached the legal recycling rate for three consecutive years, in 1997, the Taiwan Environmental Protection Agency lifted the ban on the use of foamed polystyrene food packaging containers issued in 1992; at the same time, it also made Taiwan's environment no longer flooded everywhere. With the waste of EPS, the dump site has thus eased this large and unwieldy burden.

Beijing is a city that has taken the lead in adopting recycling policies for foamed tableware. On June 1, 1997, the Beijing Municipal Bureau of Environmental Protection and the Bureau of Industry and Commerce jointly issued the "Notice on the Recycling of Discarded Disposable Plastic Meal Boxes", which stipulates the annual recycling rate that should be achieved. Established by five manufacturers of disposable plastic lunch boxes in Beijing