LCA study of discarded small electrical and electronic equipment
The objective of the study was to describe, using an objective, transparent and internationally recognised procedure, the environmental impacts connected with the take-back, transport and treatment of small waste electrical and electronic equipment (WEEE), classified as small electrical appliances, laptops, printers and mobile phones, up to the stage of replacement of the primary raw material or fuels. A functional unit (the basis to which the inputs and outputs are related), consisting in management of 1 kg of taken-back small electrical and electronic equipment (or 100 mobile telephones, 1 laptop and 1 printer), was established within the inventory analysis, where a detailed material balance of selected representative items of electrical appliances was then used as the basis for further calculations.
Both positive and negative inputs into and outputs from the environment were described and calculated within the inventory analysis of the taken-back electrical and electronic equipment for all specified processes of the company (collection, transport and treatment of waste electrical and electronic equipment). Similar to the previous study, transport distances from the collection sites to the treatment operators were determined and the environmental impact of the transport was calculated. Subsequently, a description of the treatment facilities was provided and the overall requirements for inputs (electricity, water, spare parts, etc.) were calculated using the specific consumption. These requirements were related to a functional unit. This procedure was also applied to the subsequent processing of the individual fractions created in the actual disassembly of the equipment. The treatment process was monitored up to the final recycling or disposal stage.
Data on the quantity of electrical and electronic equipment taken back (items, tonnes) was obtained from all collection channels – collection yards, collection points in companies and institutions, retailers and repair shops, collection points in schools.
The LCA study clearly confirmed the environmental benefits of the WEEE take-back system under evaluation. Savings are closely related in particular to material recovery of fractions rich in precious metals (Ag, Au and Pd). A positive balance is also achieved for copper, iron, aluminium and brass recycling. Burning of plastics presented in fractions that are rich in precious metals contributes to a reduction of the quantity of fuel required for smelting of metals. Basic data on the resulting savings are given in the table below.
Benefits for the environment in take-back of selected electrical and electronic equipment
|Category||Total||Notebook||Printer||Mobile phone||Small EEE|
|Energy savings (MWh)||93,896||0.103||0.037||0.475||0.024|
|Drinking water savings (l)||358,547,200||392||186||2,340||92.6|
|Crude oil savings (l)||6,670,682||6.809||1.912||29.264||1.723|
|Reduction in waste production (kg)||74,342,400||91.5||36||563||19.2|
|Reduction in greenhouse gas
emissions (kg CO2)
Similar to the LCA study of discarded TV sets and PC monitors, ASEKOL decided to apply the LCA study results to its system of environmental accounts distributed to ASEKOL’s clients and collection sites. Each partner thus receives an individual accounting in order to monitor its own contribution to the environment as determined on the basis of the assessment results.
For example, the following are achieved through take-back of 100 mobile telephones:
- electricity savings in the amount of 0.475 MWh. The same amount of electricity is used e.g., by a 60 W light bulb burning continuously for 11 months or is generated by a strong man working hard without any breaks for 20 months, 8 hours a day.
- crude oil savings. For example the need to extract 29.26 litres of crude oil is eliminated. The same quantity of crude oil is used, for example, to travel 222 km in a passenger vehicle with normal consumption.
- primary raw materials savings. For example, it becomes unnecessary to extract 2.4 kg of bauxite (rock serving as the raw material for the production of aluminium) or 3.7 kg of limestone.
- saving of 2300 l of drinking water while not creating the same quantity of adulterated wastewater. The same quantity is used, e.g., in taking 31 showers.
- reduction of greenhouse gases, as 122 kg of CO2 equiv. are not produced. The same amount of CO2 is produced by a passenger vehicle travelling twice from Prague to Ostrava, or a train travelling 117 times from Prague to Paris.