Green analysis of the hottest paper plastic packag

Green analysis of paper plastic packaging materials

the scientific and technological revolution has not only brought rapid development to social productivity, created huge material wealth for mankind, but also brought crisis to the ecological environment and resources. Similarly, the packaging industry is directly or indirectly related to the serious problems existing in environmental pollution and resource consumption (such as the thinning of the ozone layer, acid rain, the sharp decline of forests, drinking water pollution, the discharge of toxic wastes and urban garbage pollution). According to statistics, China's annual municipal solid waste is about 75 million tons, of which about 1/3 is packaging waste. Under the situation of the world's environmental deterioration, resource scarcity, energy shortage and other crises, there has been a green wave centered on environmental protection and resource conservation. "Green packaging" as a new scientific concept came into being. Developing "green packaging" is an inevitable choice for China's packaging industry to meet the world economic globalization, break through international green trade barriers and promote the implementation of sustainable development strategy after China's entry into WTO

in order to obtain the best environmental performance of green packaging, we must achieve "five greens" in the process of its life cycle, namely green materials, green design, green processing, green circulation and green treatment. The consumption of resources and energy by packaging, the design of container structure and the selection of production mode are all related to packaging materials. Therefore, packaging materials have become the key to determine whether packaging is "green". It is of great significance to strengthen the green analysis of packaging materials

concept analysis of green packaging

with the rise of the green wave, the progress of science and technology, the development of society and the deepening of people's understanding of green packaging, green packaging continues to give new meanings. At first, many countries enforced the recycling and treatment of packaging waste by issuing standards and decrees. The specific methods are: landfill, incineration, recycling, recycling and composting. Subsequently, Europe was the first to put forward the "3R, 1D" principle of packaging that coordinated with the environment, namely: reduce (packaging reduction); Reuse (packaging reuse); Recycle: recover (get new value); Degradable (degradation and corruption of packaging materials). In the late 1990s, the "LCA" theory was put forward. LCA (life cycle analysis/assessment) is the life cycle analysis/assessment method. The definition of packaging life cycle analysis method can be described as: according to certain objectives and requirements (reducing environmental pollution or saving natural resources), the whole life cycle of packaging products, namely the extraction, production and processing, transportation of raw materials, represents the whole process of the whole life cycle environment-friendly building concept, sales, use, waste, recycling and final treatment. It is a method of quantitative comparison and analysis

according to China's national standard gb4122-83, packaging refers to the technical measures imposed on products to achieve specific functions. China adopted the metaphor of environmental protection in 1993 and put forward the name of green packaging. Although there is no unified definition at present, according to the above analysis, green packaging can be defined as: appropriate packaging that can be recycled, recycled or degraded, and does not cause public hazards to the ecological environment and human health in the whole life cycle of the product

Green analysis of packaging materials

1. Understanding of green packaging materials

at present, there is a phenomenon in society: some consumers and non professional media often judge whether materials are conducive to environmental protection according to their only common sense, and spread the wrong information. Among them, some people unilaterally believe that plastic incineration will produce harmful gases, so it is not environmental friendly; Paper packaging incineration has no harmful substances, so it is environmentally friendly. What's more, they believe that all paper packaging is labeled "environmental protection", and plastic packaging is placed on the opposite side of green packaging. They even think that polyethylene is toxic, and paper should be comprehensively implemented instead of plastic. Some people unilaterally believe that packaging made of degradable materials or easily disposed waste is "green packaging", regardless of whether its packaging production causes environmental pollution and resource waste, and whether the packaging can be reused after use. In fact, the impact of packaging on the environment should be considered from the whole life cycle of products. For example, improper production and recycling of paper packaging do not meet the requirements of green packaging, while plastic packaging should be promoted if it achieves harmless, ecological and energy-saving treatment. Plastic has the advantage of defining the best material concept for the use of this special plate spring, which cannot be replaced by other packaging materials. A comprehensive ban on plastic will cause greater pollution. China's forest resources are limited, and the pollution caused by paper pupil is also difficult to control, so the full implementation of paper instead of plastic is neither realistic nor environmentally friendly

2. Greening of paper packaging materials

◎ environmental protection of paper packaging

during the Ninth Five Year Plan period, 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 paper, pulp molding products, edible paper products, corrugated boxes, honeycomb cardboard and other types of paper products packaging. The environmental protection of paper packaging includes: non-toxic, tasteless, breathable, which not only does not pollute the inner packaging, but also can maintain the breathing effect of the inner packaging goods, so as to achieve better storage conditions; Easy to recycle, natural decomposition, no pollution to the environment; Raw materials for production come from renewable wood and plant stems. According to the life cycle theory, there are still the following problems in the environmental protection of paper packaging in the production process and recycling: (1) pollution to the environment in the production process: high energy consumption, high water consumption, and due to the role of chemicals, it is necessary to discharge black waste liquid, pollute rivers and farmland, and release a foul smell, causing air pollution. (2) Solvent based adhesives are used in the production of cartons and boxes, and some even use toxic and harmful bubble alkaloids. (3) The recycling rate of waste paper packaging is low, and the recycling of resources is poor (see Table 1 for details)

◎ countermeasures to be taken for the greening of paper packaging

① pollution in China's paper industry and Countermeasures to be taken. Paper making raw materials are generally wood pulp, straw pulp, wheat straw pulp or mixed pulp. Among them, the waste liquid produced in the pulping process of rice straw pulp and wheat straw pulp has a serious degree of environmental pollution, and wood pulp is relatively light. China's paper industry has been mainly using wheat straw fiber as the main raw material for pulping. The annual discharge of toxic waste liquid reaches 5 billion tons, accounting for 1/6 of the national waste water discharge, of which organic pollutants account for about 1/4. In addition, it also produces waste gas and solid waste. To this end, we should take the following five measures: (1) reduce or close down small paper-making enterprises that are unable to establish recycling and pollution control systems, and develop large-scale paper-making enterprises; (2) speed up technological transformation, and actively introduce foreign advanced technology; (3) Implement the integrated development strategy of forest, pulp and paper, and gradually realize the wood base of large paper-making enterprises (4) make full use of the residues of forest cutting and processing, strengthen the recycling and utilization of domestic waste paper, and establish a domestic waste paper recycling and supply market system; (5) make full use of domestic and foreign wood and wood pulp resources, and encourage the import of logs, wood chips, wood pulp and waste paper

② promote the use of green adhesive bubble alkali. Because of its high alkalinity and strong corrosivity, it has certain damage to the skin and the package, and it absorbs CO2 to generate NaHCO3, which makes the package yellowing, moisture absorption soft, and light brittle. At present, the green adhesive technology includes: water dispersion adhesive, improved starch adhesive, solvent-free adhesive, polyvinyl acetate lotion (PVAc) adhesive and hot-melt adhesive

③ actively research and develop new environmental protection paper packaging products. At present, new environmental protection materials used for buffer packaging include honeycomb paperboard, pulp molding products and corrugated paperboard. In recent years, a series of green packaging products have been developed by using natural plant raw materials, such as reed, straw, corn stalk, bagasse, starch, bran shell, bamboo, etc. Among them, the "ecological foam" made of starch and plant fibers can replace foamed plastics

3. Greening of plastic packaging materials

◎ environmental protection of plastic packaging

the adverse effects of plastic packaging on environmental protection include: plastic and its additives and additives are polymer materials with stable chemical properties, which generally cannot degrade by themselves and are not easy to be eroded by bacteria. Therefore, plastic is difficult to decay and decompose after being discarded, forming permanent garbage, and people discard it casually, It has brought serious "white pollution" to the environment. Some plastic packaging also contains chlorine, fluorine and other elements harmful to human body

the environmental protection of plastic packaging includes: first, energy conservation. For example, the power consumption of producing a certain container of the same volume is 2.40kw · h for glass, 0.20kw · h for paper, 0.70kw · h for iron, 3.00kw · h for aluminum, and only 0.11 kW · h for plastic. Secondly, it consumes less resources, such as the comprehensive analysis and evaluation of the production process of PE plastic bags and paper bags by the environmental departments of Japan and Germany: in terms of resource consumption, based on the production of 50000 packaging bags, plastic bags need pe1000kg, paper bags consume 2500kg of paper, which is equivalent to 5000kg of wood; In terms of energy and water consumption, taking plastic bags as 1, paper bag production process consumption is 2, and water consumption is 12; In terms of waste discharge, taking plastic bag as 1, paper bag solid waste is 3.4, waste gas is 1.7, and waste water is 55. Thirdly, packaging wastes such as polyethylene and polypropylene can be incinerated for power generation. Because they are macromolecules composed of C and h, the gas generated after incineration has little impact on the environment

◎ countermeasures to be taken for the greening of plastic packaging

according to statistics, at the end of the 1990s, the demand for flexible packaging materials in the United States was 2038kt, accounting for 71.3% of the total demand for flexible packaging, and 70% in Europe, and it continued to develop with a growth momentum of 4% every year. Such a large consumption has not caused such serious "white pollution" as China. According to the experience of developed countries, to solve the problems of plastic packaging and environment, we should start with technology and social forces

① in terms of technology, there are mainly four ways according to the principle of "3R, 1D": (1) reduction. Improve the design of packaging structure and reduce the amount of waste; Select high-strength and light-weight materials to save material resource consumption; Adopt co extrusion and foam technology to reduce material consumption; Oppose excessive packaging and advocate appropriate packaging; Limit the use of disposable packaging. (2) Recycling. Beverage packaging containers and bottled containers such as detergent and emulsion paint can be recycled and reused through laws and regulations. (3) Recycling and regeneration. Materials recycling technology (including direct regeneration and modified regeneration), pyrolysis recovery monomer or chemical technology, oilization recovery fuel technology, incineration, placing a steel rod at the upper center line of the test piece to recover heat energy technology, composting technology, etc. can be used. (4) Research and develop degradable plastics and new environmental protection materials

② in terms of society, it is important to focus on governance, and there is no need to prohibit production and use. On the one hand, policies should be formulated in time to encourage the improvement of products and the development of new alternative products. On the other hand, governments at all levels should formulate detailed and clear waste and recycling regulations and policies according to local conditions, and can also follow the German model of "green dot when the experimental force is applied to the sample"; Heavily encouraged research on recycling. At the same time, we should carry out effective education on environmental protection knowledge and environmental protection laws and regulations, vigorously improve people's awareness of environmental protection, and advocate green consumption

due to the requirements of breaking through international green trade barriers and domestic environment