At present, the world has formed a consensus on the green development of plastics. Nearly 90 countries and regions have introduced relevant policies or regulations to control or ban disposable non-degradable plastic products. A new wave of green development of plastics has set off worldwide. In our country, green, low-carbon, and circular economy have also become the main line of industrial policy during the “14th Five-Year Plan” period.
The study found that although degradable plastics will develop to a certain extent under the promotion of policies, the cost is high, there will be excess production capacity in the future, and the contribution to emission reduction will not be obvious. Plastic recycling meets the requirements of green, low-carbon and circular economy. With the increase in carbon trading prices and the imposition of carbon border taxes, the mandatory addition of recycled materials will become a major trend. Both physical recycling and chemical recycling will have an increase of tens of millions of tons. In particular, chemical recycling will become the mainstream of green plastic development. In 2030, my country’s plastic recycling rate will increase to 45% to 50%. The easy-to-recycle design aims to maximize the recycling rate and high-value utilization of waste plastics. Technical innovation may generate millions of tons of metallocene plastic market demand.
Strengthening plastic recycling is a mainstream international trend
Solving the problem of white pollution caused by discarded plastics is the original intention of most countries around the world to introduce policies related to plastic governance. At present, the international response to the problem of waste plastics is mainly to restrict or ban the use of plastic products that are difficult to recycle, encourage plastic recycling, and use degradable plastic substitutions. Among them, strengthening plastic recycling is the mainstream international trend.
Increasing the proportion of plastic recycling is the first choice for developed countries. The European Union has imposed a “plastic packaging tax” on non-recyclable plastics in its member states from January 1, 2021, and also banned 10 types of disposable plastic products such as expanded polystyrene from entering the European market. Packaging tax forces plastic product companies to use recycled plastic. By 2025, the EU will use more recyclable packaging materials. At present, my country’s annual consumption of plastic raw materials exceeds 100 million tons, and it is expected to reach more than 150 million tons in 2030. Rough estimates indicate that my country’s plastic packaging exports to the EU will reach 2.6 million tons in 2030, and a packaging tax of 2.07 billion euros will be required. As the EU plastic packaging tax policy continues to advance, the domestic plastics market will face challenges. Catalyzed by the packaging tax, it is imperative to add recycled materials to plastic products to ensure the profits of our country’s enterprises.
At the technical level, current research on the green development of plastics in developed countries mainly focuses on the easy-recycling design of plastic products and the development of chemical recycling technology. Although biodegradable technology was first initiated by European and American countries, the current enthusiasm for its technology promotion is not high.
Plastic recycling mainly includes two utilization methods: physical recycling and chemical recycling. Physical regeneration is currently the mainstream plastic recycling method, but since each regeneration will reduce the quality of recycled plastics, mechanical and physical regeneration has certain limitations. For plastic products that are of low quality or cannot be easily regenerated, chemical recycling methods can generally be used, that is, waste plastics are treated as “crude oil” to be refined to achieve material reuse of waste plastics while avoiding the downgrading of conventional physical recycling products.
Easy-to-recycle design, as the name suggests, means that plastic-related products take recycling factors into consideration during the production and design process, thereby significantly increasing the plastic recycling rate. For example, packaging bags that were previously produced using PE, PVC, and PP are produced using different grades of metallocene polyethylene (mPE), which facilitates recycling.
Plastic recycling rates in the world and major countries in 2019
In 2020, my country consumed more than 100 million tons of plastic, about 55% of which was abandoned, including disposable plastic products and scrapped durable goods. In 2019, my country’s plastic recycling rate was 30% (see Figure 1), which is higher than the world average. However, developed countries have formulated ambitious plastic recycling plans, and their recycling rates will increase significantly in the future. Under the vision of carbon neutrality, our country will also significantly increase the plastic recycling rate.
my country’s waste plastics consumption areas are basically the same as those of raw materials, with East China, South China, and North China being the main ones. The recycling rates vary greatly among industries. In particular, the recycling rate of packaging and daily plastics from major disposable plastic consumers is only 12% (see Figure 2), which leaves huge room for improvement. Recycled plastics have a wide range of applications, except for a few such as medical and food contact packaging, where recycled materials can be added.
In the future, my country’s plastic recycling rate will increase significantly. By 2030, my country’s plastic recycling rate will reach 45% to 50%. Its motivation mainly comes from four aspects: first, the insufficient environmental carrying capacity and the vision of building a resource-saving society require the whole society to increase the plastic recycling rate; second, the carbon trading price continues to increase, and every ton of plastic recycled will make plastic The whole life cycle of carbon reduction is 3.88 tons, the profit of plastic recycling has been greatly increased, and the recycling rate has been greatly improved; thirdly, all major plastic products companies have announced the use of recycled plastics or the addition of recycled plastics. The demand for recycled materials will increase significantly in the future, and recycling may occur. The price of plastics is inverted; fourth, carbon tariffs and packaging taxes in Europe and the United States will also force my country to significantly increase the plastic recycling rate.
Recycled plastic has a huge impact on carbon neutrality. According to calculations, in the entire life cycle, on average, every ton of plastic recycled physically will reduce carbon dioxide emissions by 4.16 tons compared with non-recycled plastics. On average, every ton of plastic recycled chemically will reduce carbon dioxide emissions by 1.87 tons compared with non-recycled plastics. In 2030, my country’s physical recycling of plastics will reduce carbon emissions by 120 million tons, and physical recycling + chemical recycling (including the treatment of deposited waste plastics) will reduce carbon emissions by 180 million tons.
However, my country’s plastic recycling industry is still facing many problems. First, the sources of waste plastics are scattered, the shapes of waste plastic products vary greatly, and the types of materials are diverse, making it difficult and costly to recycle waste plastics in my country. Second, the waste plastic recycling industry has a low threshold and is mostly workshop-style enterprises. The sorting method is mainly manual sorting and lacks automated fine sorting technology and industrial equipment. As of 2020, there are 26,000 plastic recycling companies in China, which are small in scale, widely distributed, and generally weak in profitability. The characteristics of the industry structure have led to problems in the supervision of my country’s plastic recycling industry and the huge investment in regulatory resources. Third, industry fragmentation has also led to intensified vicious competition. Enterprises pay more attention to product price advantages and cutting production costs, but despise technological upgrading. The overall development of the industry is slow. The main way to use waste plastic is to make recycled plastic. After manual screening and classification, and then through processes such as crushing, melting, granulation, and modification, waste plastics are made into recycled plastic particles that can be used. Due to the complex sources of recycled plastics and many impurities, product quality stability is extremely poor. There is an urgent need to strengthen technical research and improve the stability of recycled plastics. Chemical recovery methods are currently unable to be commercialized due to factors such as the high cost of equipment and catalysts. Continuing to study low-cost processes is a key research and development direction.
There are many constraints on the development of degradable plastics
Degradable plastics, also known as environmentally degradable plastics, refer to a type of plastic that can eventually be completely degraded into carbon dioxide, methane, water and mineralized inorganic salts of their contained elements, as well as new biomass, under various conditions in nature. Limited by degradation conditions, application fields, research and development, etc., the degradable plastics currently mentioned in the industry mainly refer to biodegradable plastics. The current mainstream degradable plastics are PBAT, PLA, etc. Biodegradable plastics generally require 90 to 180 days to be completely degraded under industrial composting conditions, and due to the particularity of the materials, they generally need to be separately classified and recycled. Current research focuses on controllable degradable plastics, plastics that degrade under specified times or conditions.
Express delivery, takeout, disposable plastic bags, and mulch films are the main application areas of degradable plastics in the future. According to my country’s “Opinions on Further Strengthening the Control of Plastic Pollution”, express delivery, takeout, and disposable plastic bags should use biodegradable plastics in 2025, and the use of biodegradable plastics in mulch films is encouraged. However, the above-mentioned fields have increased the use of plastics and degradable plastic substitutes, such as using paper and non-woven fabrics to replace packaging plastics, and mulching films have strengthened recycling. Therefore, the penetration rate of biodegradable plastics is well below 100%. According to estimates, by 2025, the demand for degradable plastics in the above fields will be approximately 3 million to 4 million tons.
Biodegradable plastics have limited impact on carbon neutrality. The carbon emissions of PBST are only slightly lower than that of PP, with a carbon emission of 6.2 tons/ton, which is higher than the carbon emissions of traditional plastic recycling. PLA is a bio-based degradable plastic. Although its carbon emissions are low, it is not zero carbon emissions, and bio-based materials consume a lot of energy in the process of planting, fermentation, separation and purification.
Post time: Aug-06-2024