Green Analysis of Paper and Plastic Packaging Materials

The scientific and technological revolution has brought rapid development to the productive forces of the society, created enormous material wealth for mankind, and brought crisis to the ecological environment and resources. Similarly, the packaging industry and the serious problems in environmental pollution and resource consumption (such as: thinning of the ozone layer, acid rain, sharp decline in forests, drinking water pollution, toxic waste discharge, and urban garbage pollution) all have direct or indirect consequences. relationship. According to statistics, China's annual urban solid waste is about 75 million tons, of which about 1/3 is packaging waste. In the context of the deterioration of the world's environment, lack of resources, and energy shortages, a green wave centered on protecting the environment and conserving resources has been set off. "Green Packaging" emerged as a new scientific concept. The development of "green packaging" is the inevitable choice for China's packaging industry to meet the global economic globalization, break through the international green trade barriers and promote the implementation of sustainable development strategy after joining the WTO.

In order to achieve the best environmental performance of green packaging, it is necessary to achieve "five greens" in the course of its life cycle, namely, green materials, green design, green processing, green circulation, and green processing. Packaging's consumption of resources and energy, design of container structure and choice of production methods are all related to packaging materials. Therefore, packaging materials become the key to decide whether packaging is “green”, and it is extremely important to strengthen the green analysis of packaging materials. significance.

Green Packaging Concept Analysis

With the rise of the green wave, the advancement of science and technology, the development of society, and the deepening of people’s understanding of green packaging, green packaging continues to pay for new meaning. Initially, many countries are enforcing standards and decrees to force the recycling of packaging waste. Specific methods include landfill, incineration, recycling, recycling, and composting. Subsequently, Europe first proposed the principle of packaging “3R, 1D” that is compatible with the environment, namely: Reduce (reduction of packaging); Reuse (recycling); Recycle (recycling): Recover (get new value) ); Degradable (degradation of packaging materials). In the late 1990s, the "LCA" theory was put forward again. LCA (Life Cycle Analysis/Assessment) is Life Cycle Analysis/Assessment. The definition of packaging life cycle analysis method can be described as: according to certain target requirements (reducing environmental pollution or saving natural resources), from the entire life cycle of packaging products, namely the extraction of raw materials, production and processing, transportation, sales, use, disposal and recycling The entire process of final processing is a method of quantitative analysis and analysis.

According to China's national standard GB4122-83, it can be seen that packaging refers to the technical measures imposed on the product in order to achieve a specific function. China adopted the metaphor of environmental protection in 1993 and proposed the name of green packaging. Although there is no unified definition at present, according to the above analysis, green packaging can be defined as: moderate packaging that can be recycled, reused, or degraded, and that does not pose a hazard to the ecological environment and human health throughout the product lifecycle.

Green Analysis of Packaging Materials

1. Understanding of green packaging materials

At present, there is a phenomenon in the society: Some consumers and non-professional media reporters often judge whether or not the material is conducive to environmental protection based on their own common sense, and they often use rumours. Among them, some people think in one-sidedly that: plastic incineration will produce harmful gases, so it is not environmentally friendly; paper packaging incineration does not generate harmful substances, so it is environmentally friendly. What is even worse is that all paper packaging is labeled as "environmental protection," and plastic packaging is placed on the opposite side of green packaging, and even that polyethylene is toxic, should be fully implemented by paper and plastic. Some people still think in one-sidedly that packages that are made of easily-degradable materials or that are easily handled by waste are “green packaging”, and do not ask whether the packaging production causes environmental pollution and waste of resources, and whether the packaging can be reused after use. . In fact, the impact of packaging on the environment should be considered from the entire life cycle of the product. If the improper production and recycling of paper packaging do not meet the requirements of green packaging, plastic packaging should be promoted if it is harmless, ecological, and energy-saving. Plastics have the advantage that other packaging materials cannot be replaced, and a total ban on plastics will cause greater pollution. China's forest resources are limited, and the pollution caused by pupil paper is also difficult to control. Therefore, the full implementation of paper-based plastic molding is neither realistic nor environmentally friendly.

2. Greening paper packaging materials

â—ŽEnvironmental protection of paper packaging

During the “Ninth Five-Year Plan” period in China, paper packaging accounted for 28% of the total output value of the packaging industry, ranking first, reaching 12.3 million tons. At present, there are packaging papers, pulp molded products, edible paper products, corrugated boxes, and honeycomb paperboards in the packaging of paper products. The environmental protection of paper packaging includes: non-toxic, odorless, breathable, not only polluting the inner packaging, but also maintaining the respiration of the inner packaged goods, achieving better storage conditions; being easy to recycle, natural decomposition, and not polluting the environment; production Raw materials come from renewable wood and plant stems. According to the life cycle theory, paper packaging has the following problems in terms of environmental protection in the production process and recycling: (1) Environmental pollution in the production process: high energy consumption, high water consumption, and discharge due to the effects of chemicals Black effluent, which pollutes rivers and farmland, also emits odor odors that cause air pollution. (2) The use of solvent-based adhesives in the production of cartons and boxes or even the use of toxic and harmful silicates. (3) The recycling rate of discarded paper packages is low and the use of resources is poor (see Table 1).

â—Ž Measures to be taken to green paper packaging

1 China's Paper Industry Pollution and Countermeasures

Papermaking raw materials are generally wood pulp, straw pulp, wheat straw pulp or mixed pulp. Among them, the waste liquid produced by the straw pulp and wheat straw pulp during the pulping process has relatively serious environmental pollution, and the wood pulp is relatively light. China's paper industry has been mainly using wheat straw fiber as the main raw material for pulping. Each year it discharges 5 billion tons of toxic waste liquid, accounting for 1/6 of the national wastewater discharge, of which organic pollutants account for about 1/4. In addition, waste gas and solid waste are also produced. To this end, the following five measures should be taken: (1) reduce or close the inability to establish small paper-making enterprises that recycle and control pollution systems, and develop large-scale paper-making enterprises: (2) Accelerate technological transformation and actively introduce advanced foreign technology (3) Implement the integrated development strategy of forestry, pulp and paper, and gradually realize the material base of large-scale papermaking enterprises (4) Make full use of the residues left by forest processing, and strengthen the collection and utilization of domestic waste paper, and establish domestic waste paper; Market system for recycling and supply: (5) Make full use of foreign timber and wood pulp resources, and encourage the import of logs, wood chips, wood pulp and waste paper.

2 promote the use of green adhesive

Due to its basicity and strong corrosiveness, scoroders have some damage to the skin and the packaged goods, and it absorbs CO2 to generate NaHCO3, which makes the package yellow, absorbs moisture and becomes light and brittle. Current green adhesive technologies include: water-dispersible adhesives, modified starch adhesives, solvent-free adhesives, polyvinyl acetate emulsion (PVAC) adhesives, and hot melt adhesives.

3 Actively develop new environmentally-friendly paper packaging products At present, new environmentally friendly materials for buffer packaging include honeycomb paperboard, pulp molded products and corrugated paperboard. In recent years, a series of green packaging products have been developed using natural plant materials such as reeds, rice straw, corn stalks, bagasse, starch, clam shells, and bamboo. Among them, "eco-foam" made from starch and plant fibers as raw materials can replace foam plastics.

3, green plastic packaging materials

â—Ž Environmental protection of plastic packaging

The adverse effects of plastic packaging on environmental protection include: plastics, their additives, and additives are all polymer materials. They are chemically stable, generally cannot be degraded by themselves, and are not easily eroded by bacteria. Therefore, plastics are difficult to rot and difficult to decompose after being discarded. Permanent rubbish, coupled with the fact that people are thrown away, has brought serious "white pollution" to the environment. Some plastic packaging also contains chlorine, fluorine and other harmful elements.

The environmental protection of plastic packaging includes: First of all, energy saving, such as the power consumption of a certain volume container, glass is 2.40 KW·h, paper is 0.20 KW·h, iron is 0.70 KW·h, and aluminum is 3.00 KW· h, while plastic is only 0.11 KW·h. The second is less consumption of resources, such as the comprehensive analysis and evaluation of the production process of PE plastic bags and paper bags by the Japanese and German environmental authorities: in terms of resource consumption, based on the production of 50,000 bags, the plastic bag needs PE1000kg, and the paper bag consumes 2500kg of paper. 5,000 tons of wood for energy conversion and water consumption; 1 for plastic bags, 2 for paper bag production, 12 for water consumption, 1 for plastic bags, and 3.4 for paper waste. The waste gas is 1.7 and the waste water is 55. Third, packaging wastes such as polyethylene and polypropylene can be burned to generate electricity. Since they are all large molecules of C and H, the gas generated after incineration has little effect on the environment.

â—Ž Measures to be taken to green plastic packaging

According to statistics, at the end of the 1990s, the demand for flexible packaging materials in the United States was 2,038 kt, accounting for 71.3% of the total demand for flexible packaging, and 70% in Europe, and continued to grow at a rate of 4% each year. Such a large amount of consumption has not caused such "white pollution" as our country is serious. According to the experience of developed countries, solving the problems of plastic packaging and the environment should begin with both technical and social forces.

1 In terms of technology, there are four main ways to follow the "3R, 1D" principle: (1) Reduction. Improve the design of packaging structure, reduce the amount of waste; use high-strength and lightweight materials to save material resource consumption; adopt co-extrusion and foam technology to reduce the amount of materials; oppose over-packaging and promote proper packaging; limit the use of disposable packaging. (2) Recycling and reuse. Bottled containers such as beverage packaging containers and detergents, latex paints, etc. can be collected and reused by law. (3) recycling and regeneration. Materials recycling technology (including direct regeneration and modified regeneration), pyrolysis recovery monomer or chemical technology, oil recovery fuel technology, incineration recovery heat energy technology, and composting technology can be used. (4) Research and development of degradable plastics and new environmentally friendly materials.

2 In society, the emphasis is on governance and there is no need to prohibit production and use. On the one hand, policies that encourage the improvement of products and the development of new alternative products should be formulated in a timely manner. On the other hand, governments at all levels should formulate detailed and clear regulations and policies on disposal and recycling according to local conditions. They can also follow the model of the "Green Point Company" in Germany. Heavy investment encourages research on recycling. At the same time, we will conduct effective education on environmental protection and environmental protection laws for the citizens, vigorously raise the people's awareness of environmental protection and advocate green consumption.

Due to the requirement of breaking through the international green trade barriers and the rise of domestic environmental protection undertakings and government support, China's green packaging industry is also rapidly developing. The use of environmentally-friendly packaging materials is increasing, market share is gradually increasing, and the market for the green packaging industry is continuously expanding. However, compared with developed countries, China's green packaging industry is still lagging far behind, and the pace of development is not fast enough and unbalanced. There are still some problems, such as insufficient investment in capital, technology, and talent, and more "slogans" than actual ones. The phenomenon of action and so on. China is a country with a population of 1.3 billion people and relatively insufficient resources. Vigorously developing green packaging not only has important strategic significance, but also