Källsortering: teori, metod och implementering
The primary interest of public sanitation is to maintain a hygienic and tidy city environment. The modern consumer society is based on a large production of goods and products with destruction of waste as a final step. The present sanitation system is a necessary link in the system serving the consumer society. It follows that the collection and destruction of household waste promotes the need for new products and as such leads to an increase in consumption. It is anticipated that this system will collapse in a long-sighted sustainable society. Future systems for the treatment of residual materials should be encompassed in closed cycles of materials in society and added to those providing waste generation.
The present alternative for steering residual materials is source separation. That the Swedish population is prepared for an increased responsibility in recycling residual materials has been shown in studies in Göteborg, north west Skåne and Borås. However, strong motivation and a sufficiently comfortable collection system are necessary as shown by the significant correlation between ease of use and increased collection amount. Owner households successfully source separated paper, glass and biodegradable material without a need for help. However, source separation in apartments in Borås was greatly improved by offering simple under-the-sink technology as an aid. This study showed that collected household wastes from owner households decreased from 14 kg to 4 kg per household and week (75%) while in apartments the decrease was from 6.3 to 2.3 kg (65%) after the commencement of source separation. Guidelines for the implementation of source separation are proposed.
A full assessment of the success of source separation requires the application of several approaches to allow a holistic picture. Degree of recycling and purity are central approaches because they are comparable between experiments and areas involved. Absolute amounts measured as "Material Recovery Rate" are unique to each sampling area and difficult to compare. A holistic approach to the assessment of source separation will include investigations of availability to users, participation rate, resource conservation, environmental consequence analysis and environmental economics.
Although good collection results are obtained it cannot be expected that source separation will be the panacea in the construction of a long term sustainable society. Source separation as a technology and a social movement is a necessity in the treatment of residuals and should be incorporated in a new resource-saving technology. However, source separation technology is constantly subject to incorporation in modern waste disposal. Recycling without a change in the system for production and consumption has no long-term effect on the use of resources or environmental protection. On the other hand, a combination of source separation with a new outlook for production and consumption can raise source separation to a key concept in a closed cycle society.