In the context of "3060 carbon peak carbon neutrality", more and more "low-carbon products" and "green technologies" enter the market, but how to evaluate whether a product and technology is really low-carbon green is a key issue. According to the 3R principle (reduce,reuse,recycle), the reduction and recycling of product materials is the key to reduce the environmental impact of products. However, it is still a difficult problem to accurately evaluate the environmental-economic benefits and the contribution of resource recovery enterprises.
Environmental Product Certification EPD(Environmental Product Declaration, also known as Type III Environmental Product Declaration) is a comprehensive disclosure of environmental impact information on the entire life cycle of a product that is verified by a third party, scientifically, comparable, and internationally recognized. EPD can help buyers and consumers better understand the sustainability and environmental impact of products. More enterprises will carry out EPD product certification to attract consumers, and buyers, consumers and designers will be more willing to choose EPD certified products under the condition of increasing green awareness.
According to the recycled material reuse into the production stage of the location of the
can be divided into:
Closed loop recovery, semi-closed loop recovery and open loop recovery
Closed-loop recovery of
in closed-loop recycling, the recycled material is returned to the production system of the same type of product, and the form of the material does not change.
(For example: in the recycling process of plastic bottles, plastic bottles are still used as production materials into the production system of plastic bottles after recycling, and the form and properties of the materials have not changed)
Semi-closed loop recovery of
in semi-closed loop recycling, the recycled material will enter the production system of another product, and the properties of the material itself will not change.
(For example: construction steel will not return to the production system of construction steel after recycling, but will enter the production system of ship steel or other steel to completely replace the primary material. The properties of the material itself do not change. Steel is still steel, but it enters the production system of another product)
Open Loop Recovery
in open-loop recycling, the recycled material enters the production system of another product. Open-loop recycling is also called downgraded recycling.
(For example: plastic packaging-plastic board, plastic packaging cannot return to the production system of plastic packaging after recycling, and enters the production system of plastic board. However, because its material properties have changed and cannot completely replace the primary material, the properties of the material have been degraded and belong to open-loop recycling.)
the harvest phase will create allocation problems, allocation of what?
01 Burden Burden
refers to the energy consumption, emissions and pollution generated by the recycling process.
02 Revenue
Revenue Refers to recycled materials/products after recycling.
these recycled materials are put on the market again to produce the corresponding value, that is, the use of these materials is equivalent to reducing the input of raw materials. The value of these deductions, whether economic or environmental, will be disputed. The key question is how is the distribution between the upstream system where the recycling takes place and the downstream system where the recycled material is used? The most common models of distribution in recycling are:
-
Cut-off procedure (Cut-off)
-
System expansion
-
Economic Allocation Method (Economic allocation)
-
oriented input oriented
-
output-oriented oriented/ Substitution
-
Value Correction Substitution (Value-corrected substitution)
-
Multiple recovery method (Multiple recycling method)
01. Cut-off method
in the cut-off method, all environmental impacts caused by the production of a product are directly allocated to the product itself. This method does not need to consider other product life cycle data.
Recycled and primary materials enter the production stage at the same time, reducing the environmental impact of the material. In this process, the recovery content is important. This may be a way to reduce the environmental impact of the system, because the impact of recycled materials is often less than that of primary materials. Increasing the collection rate is also beneficial because it reduces the impact of waste disposal.
System expansion method
ISO14044 tend to avoid allocation by expanding the system, which effectively forms a closed system. The system of another product is added to the original system and incorporated into the boundary of the whole system model, which improves the integrity of the system.
taking aluminum products as an example, starting from the mining of raw materials, the life cycle system of an aluminum product is expanded to the entire aluminum product that can use recycled materials. Because aluminum recycling does not result in a change in inherent properties, recycling can be viewed as a closed loop cycle system.
03. Economic allocation method
Due to the problem of economic distribution in recycling, recycling materials in production changes production costs. The economic allocation method is mainly used when the output is not fully available or the market is distorted, for example, the cost of the recovery process may be determined by regulations or class classification costs.
For example, in an open-loop recycling system for waste products, the materials used in the collection and disassembly process produce 100 yuan, and the reprocessing into a new product system produces a value of 150 yuan, which brings the total output value to 250 yuan.
Since the value of the materials used accounts for 40% of the total output value (100/250), 40% of the environmental burden of the process is allocated to the system that provides the materials used, and the remaining 60% is allocated to the system that subsequently uses recycled materials.
in the semi-closed loop scheme shown in the figure above, the recycled material is returned to the original product system. We assume that there is 1 reflux in the 5kg material used. According to the economic distribution, 40% of the collection and disassembly process is allocated to the original product system. However, 20% of the remaining 60% (5kg is 1kg), that is, 12%, is then added back to the original system. A total of 40% + 12% = 52% of the collection and disassembly process is assigned to the original product system. This method of economic allocation can be seen as a modification of the cut-off approach.
04. Oriented input method
the input-oriented method is the same as the cut-off method, which only considers the cost of raw materials and waste in the production system of the product, and the output of recycled materials does not belong to the product system.
05. Output-oriented/Substitution.
the output-oriented/alternative approach is to reprocess waste into recycled materials to replace raw materials at the end of the life cycle, and is suitable for semi-closed-loop recycling where the inherent properties of recycled materials and raw materials are the same or similar. In the closed loop, the recycled material completely replaces the raw material.
06. Value Amendment Substitution
the value correction substitution method solves the different properties of recycled materials and raw materials, and sets the ratio of raw material value and recycled material value (P prim /P sec) as the inherent property of recycled materials, which is applied in open-loop and semi-closed-loop recovery. For example, in the table below, the value of primary materials (primary materials) is 100 per cent, the value of secondary materials (recycled materials) is 90 per cent, and multiplied by the quantity of materials, the difference between the corrected value of inputs and outputs is the environmental impact of the entire product system.
the advantage of the value correction method is that it can deal with changes in the inherent properties of recycled materials and is most suitable for materials with a good recycling market. When the market is disturbed by external factors, the price of recycled materials may not fully reflect their quality, thus misestimating the environmental impact they avoid.
Multiple recovery methods
-
RR:Recovery Rate Recovery Rate
-
Y:Yield of recovery process recovery phase
-
Xpr:Impact of primary production Primary Products
-
Xre:Impact of secondary production secondary products
-
n:number of life cycles
-
Qini:Initial amount of primary product Initial Quantity of Primary Product
-
Qcum:Cumulative amount of primary product Primary Product
as n increases, Qcum will gradually approach Qini/(1-RR). This means that if the recovery rate is 0.8, the cumulative steel volume of 1 ton of raw steel is 5 tons. The environmental impact of a product can be expressed in the following equation:
as the number of continuous life cycles increases, the environmental impact will continue to decrease because the impact of recycled materials is smaller than that of virgin materials. After several life cycles, the impact reaches an almost constant value.
The multiple recovery method can also be applied to open-loop or semi-closed-loop recovery, and other metals and materials where the inherent properties of the material have not changed or only slightly changed.
There is no LCA in the best or worst distribution method, we need to choose the most suitable distribution method in practice to minimize the environmental impact of the product. Different allocation models may produce different assessment results, and LCA studies need to include the impact results of other allocation models in the sensitivity analysis.
Whether in the environmental product certification EPD mentioned at the beginning of the article or in the ISO14067 product carbon footprint certification PCF(Product Carbon Footprint) released in 2018, the life cycle assessment LCA is a key part. The LCA recovery and distribution model provides a more scientific method for accounting the environmental footprint of resource recovery behavior, and can also more accurately assess the costs and benefits of recycled products. At the same time, it provides a reference for the development of economic incentive policies for various stakeholders.
The above is the introduction of Ankejie's testing and certification on recycled materials. It is for reference only. Some materials come from the Internet and do not represent the views of Ankejie's testing technology and are responsible for its authenticity. If you are involved in the content of the work, copyright and other issues, please contact us within 30 days, we will delete the content in the first time!
