A new idea of LCA for the hottest evaluation of pa

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The development of packaging materials is closely related to the development of human civilization and technological progress. With the development of modern industry, a number of industrialized products have become commonly used packaging materials. As early as the 19th century, industrialized products (such as paper, cardboard, metal plates, glass, etc.) have been used to make boxes, cans, bottles, bags and other packaging. With the development of synthetic material industry in the 20th century, plastics are widely used in packaging. However, the extensive use of industrial materials such as plastics has caused serious pollution and threatened people's health. The more developed countries and regions have, the higher the per capita consumption of packaging materials and the greater the amount of packaging waste. According to incomplete statistics, the current per capita consumption of packaging materials in the world is 145kg/year, of which plastic accounts for about 10% - 15%. The quality of general national packaging waste (PSW) accounts for about 1/5 ~ 1/3 of the quality of municipal solid waste (MSW). If it goes on like this, it will lead to very serious environmental pollution and waste of resources, especially the "white pollution" brought by plastic packaging waste that cannot be completely degraded for a long time, which brings great harm to the environment and the invisible protection of experimental equipment

with people's deepening understanding of the world environmental crisis and resource crisis, a global wave of environmental protection has been set off. In 1987, the United Nations Environment and development what is the servo valve of microcomputer screen hydraulic universal testing machine? The Committee issued a declaration entitled "our common future", formally proposing that the way of life and production of mankind should be adjusted to be more friendly and harmless to the environment. The control of environmental pollution should not be placed only after the pollution, but also in the adjustment of lifestyle and production process. This principle prompted people to pay attention to the whole process of product manufacturing, use, recycling and waste in the late 1980s, and the environmental performance evaluation of products should be comprehensively evaluated from the whole life process of products, that is, the whole process of "cradle to grave", which produced LCA

lca definition and structure

lca (life cycle analysis), namely "life cycle analysis method". The international organization for standardization defines LCA as a method of summarizing and evaluating the environmental impact and potential impact of all inputs and outputs of a product (or service) system during its entire life cycle. This method points out that the environmental performance of packaging products (packaging materials, packaging technology) cannot be evaluated only from the impact of packaging waste on the environment, but must be evaluated from the whole life cycle of packaging products, that is, the whole process of raw material extraction, production and processing, transportation, sales, use, reuse or recycling, until the final treatment, using quantitative comparison to evaluate the environmental performance of packaging products. This analysis method can be used for comparative analysis to evaluate who has the best environmental performance among several packaging products; It can also be used as the whole process analysis of a product to seek the impact of each link in the whole process on the environment, so as to adjust our industrial policy, technical policy, production process and material selection

the basic structure of LCA can be summarized into four organically linked parts: defining objectives and determining scope, inventory analysis, impact evaluation and improvement evaluation. The basic relationship is shown in Figure 1

Figure 1 basic structure of LCA

defining objectives and determining scope is the first step of LCA, which directly affects the whole. Therefore, it is also customary to σ B is called the strength limit (UTS), an evaluation procedure and the final research conclusion. Defining the goal is to clearly state the goal and reason of this LCA and its possible application areas. The determination of the research scope should ensure that it can meet the research purpose, including defining the studied system, determining the system boundary, explaining the data requirements, pointing out the main assumptions and limitations, etc

inventory analysis is an objective quantitative process based on data for the energy and raw material requirements of a product, process and activity in its whole life cycle and the discharge to the environment (wastewater, exhaust gas, solid waste and other environmental releases)

impact assessment is a quantitative or qualitative characterization evaluation of the degree of environmental impact identified in the inventory analysis stage, that is, to determine the material and energy exchange of the product system and its impact on the external environment. This evaluation should consider the impact on the ecosystem, human health and other aspects. Improvement evaluation is a systematic evaluation of the needs and opportunities to reduce energy consumption, raw material use and environmental release throughout the life cycle of products, processes or activities. This analysis includes quantitative and qualitative improvement measures, such as changing product structure, updating and selecting raw materials, changing manufacturing processes and consumption patterns, and waste management

Application of LCA

at present, LCA technology has attracted international attention, and this analytical method has been used to evaluate packaging materials in some developed countries (such as Japan, the United States, Germany, etc.). Packaging materials are closely related to the environment from raw material selection, material processing, manufacturing to waste treatment, recycling, utilization and other stages. Through LCA technology, these impacts can be quantitatively evaluated, and corresponding improvement measures can be formulated, which can effectively reduce the degree of environmental harm of packaging materials. Haruo Sasaki, the Japanese Packaging Association, pointed out in the "development prospects of packaging industry in the era of environmental awareness" that it is entirely possible to promote the application of LCA technology. It is meaningless to argue with the traditional conservative ideas or old knowledge held by everyone. In other words, the application of packaging materials should be determined by LCA research. This is particularly important for enterprises that have established environmental awareness

in order to protect the environment, the effect of packaging materials on the environment must be minimized. Therefore, packaging designers should choose and use packaging materials that are harmless to the environment or the least harmful to the environment. The selection of materials shall be based on the principle of reducing dosage and damage to the environment. Recyclable or degradable materials shall be selected as far as possible, and they shall have appropriate physical and chemical properties, mechanical properties and reliable protective properties in the process of use

from the perspective of environmental protection and sustainable development, what is good packaging? What is a good packaging waste treatment plan? LCA packaging countermeasures can be embodied as four "R" principles. Among them, reduce is the top priority, and reuse, recycle and recover have their own advantages

reduce: under the condition of ensuring the main functions of packaging, the primary consideration of packaging is to reduce the consumption of packaging materials as much as possible. According to the research, the best package for the environment is the one with the lightest weight; When the recyclability of packaging conflicts with weight reduction, weight reduction is more beneficial to the environment

reuse: it refers to the reuse of all or part of the packaging, such as the reuse of beer bottles

recycle: recycle packaging materials for reprocessing for use in different fields, such as cans or recycling of waste paper. Recycling and re granulation of waste plastics also belong to recycle

recover (obtain new value, conversion): for example, obtain the energy of waste conversion through incineration

with regard to the current domestic packaging waste pollution, visual pollution can be eliminated by improving the garbage collection and treatment system and management; However, it is necessary to be cautious to force the selection and implementation of a certain packaging material and the method of collection and treatment (including recycling), and the LCA analysis should be done in combination with the actual situation

give an example

is the choice of reusable glass bottles or disposable metal cans for beverages? People often only see the moment when they are discarded after consumption, so it is easy to judge that glass bottles must be better than cans for the environment - but consumption and abandonment are only one of these packaging containers in the whole life cycle. What should we pay attention to? Let's go and have a look! The impact on the environment should be considered in all links, from the mining and processing of their respective raw materials into containers, to the packaging of food, and then the transportation and distribution of packaged food to consumers, and even how to store it in consumers' homes. Therefore, LCA method needs to solve: which one of quartz (glass bottle raw material) and bauxite (cans raw material) mining is more destructive to the environment? Which one consumes the most energy, glass smelting or bauxite electrolysis, and how do they affect the environment? How to evaluate the impact of the energy consumed in the air return transportation on sustainability when the weight of glass bottles exceeds that of cans? Glass bottled milk needs to be refrigerated from the factory to the home. How to evaluate the impact of the energy consumed on the greenhouse effect and the CFC gas emitted from refrigeration on ozone? And so on. Through the comprehensive analysis of LCA above, it is concluded whether to choose reusable glass bottles or disposable metal cans

reprinted from: China's packaging industry

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