Practices And Technologies For The Maximum Reduction Of Household Waste

Transcription

1 Practices And Technologies For The Maximum Reduction Of Household Waste Authors: Ludwig Sahm, Stephan Weissenbacher SSI Schäfer, Fritz Schäfer GmbH, Germany, Sewage, waste air and refuse are just some of the many waste by-products of modern industrial society, reflecting the technological age in which we live, and they are potentially dangerous to the individual and society in general. Nowadays, pollution is not simply an offence or subject of local or national interest. The continued contamination of air, soil and water knows no boundaries. Technical measures and environmental controls to protect air, soil and water from harmful pollution have been developed. Therefore, it is important to put the knowledge and experience of the technical experts to use. In Germany, the contribution of recycling to greenhouse gas reduction is considerable. Twenty years ago the waste management sector polluted the climate with almost 38 m tonnes of climate-damaging gas (CO 2, methane etc.). Today, with recycling activities and the ban on landfilling untreated waste materials (since 2005) it relieves the climate by 18 m tonnes annually which equals to the annual output of 7.7 m vehicles or almost 20 % of the cars registered in Germany. So coming to the carbon footprint of the German waste management industry the saving of CO 2 is higher than the emission. The new study Climate protection potentials in the waste management sector, jointly produced by the Federal Environment Ministry, Federal Environment Agency and Federation of the German Waste, Water and Raw Materials Management Industry anlayses the potential usage of residual solid waste, paper, plastics, biowaste, glass and used wood for recycling and generating energy.

2 Overall result of greenhouse gas standard assessment for Germany* 2006 actual 2020 T 2020 A 2020 AT 1,000t 1,000t 1,000t 1,000t CO 2 -eq/a CO 2 - eq/a CO 2 -eq/a CO 2 -eq/a Disposal of residual waste -2,344-6,009-1,435-3,861 Utilisation of separately collected recyclable materials -8,926-11,589-11,356-15,308 Used wood utilisation -6,503-7,897-6,834-8,299 Total -17,773-25,496-19,625-27,468 * 2020 T, 2020 A and 2020 AT present different future scenarios. Details on the assumptions on which these are based are given on page 14 of the study ( This means that the separate collection and recycling of waste does not only save natural resources, but also protects the climate. Increasing environmental awareness, stimulated by the demands of an ecology under increasing stress, together with ever-diminishing waste disposal resources call for effective measures to significantly reduce the large volume of waste which our modern society produces. The preconditions for this, however, are clear political decisions at both governmental and local level. Since 1979 SSI Schaefer has been focusing on the separate collection of recyclables with colour-coded bins as well as on the recycling possibilities of these materials. Concentrating on the subject "recycling" it was important to us to develop a cost-effective and ecologically friendly collection system which can be implemented without involving enormous technical and financial resources, which allowed the collection of the maximum volume of high quality recyclable materials, thus minimising the remaining waste volume, and which at the same time offered a high standard of hygiene and was user-friendly. Apart from technical requirements, the most important basis for separate collection is the public's environmental awareness, active involvement, and the back-up of the necessary laws and regulations.

3 The bins required for the separate collection of recyclables and residual waste are purchased by municipalities or private contractors and distributed to residents. The costs for this are included in the total waste management costs including collection and disposal. The European Community has been concentrating on the subject of waste reduction for a long time. The Governments of several member states have already taken definite steps in the form of laws to reduce packaging materials and to reclaim recyclables which far exceed the European targets as well as the ban on uncontrolled landfilling like in Germany (since 2005). The priorities in a sustainable waste management should be as shown in the following waste hierarchy: For reasons of environmental protection it is important 1) to avoid waste generation where possible, 2) to keep those materials which can not be avoided at a minimum, 3) to reuse materials 4) to recycle waste materials which can not be avoided or reused 5) to gain energy from waste (waste to energy) 6) and the very last option to dispose of waste materials in a controlled way by landfilling (gas collection) or incineration, if the first five options are not possible Diagram No. 1 shows the components of waste (e.g. in Asian countries).

4 Ferrous Other Inorganic Glass Aluminium Bulky Yard Waste Wood Biowaste Rubber and Leather Textiles Plastics Paper Diagram 1 Biowaste 56,29% Paper 8,23% Plastics 13,04% Textiles 1,29% Rubber and Leather 0,41% Wood 1,84% Yard Waste 6,90% Glass 1,55% Ferrous 2,07% Other Inorganic 6,41% Aluminium 0,30% Bulky Waste 1,29% Efficient Waste Reduction e.g. in Asia with the separate collection of organic waste:

5 If the volume and weight of waste are to be reduced effectively, we will have to tackle the problem, starting with the biggest components, i. e. with organic waste and then with paper/cardboard, glass, metals, textiles and plastics (dry recyclables). According to the above mentioned study the most significant CO 2 savings in Germany are achieved with the recycling of paper and cardboard (at present almost 6 m tonnes of CO 2 equivalents annually which can still be increased considerably), used wood (6.5 m tonnes), followed by lightweight packagings (2.3 m tonnes) and the recovery of energy from residual waste (e. g. incineration). Apart from the appropriate collection system the quality of the public information campaign to advise the residents of the recycling scheme is also decisive for the collection quota. As initially mentioned, such a success, however, requires clear political decisions at local level. For an effective reduction it is thus important to introduce an integrated waste management scheme which is compatible and flexible, as already being used in many European cities. For example, all container types and sizes produced by SSI Schäfer can be emptied with the SAME vehicle However, there has to be enough bin capacity to accomodate the remaining waste, otherwise experience shows that the residual waste is thrown into the recycling bin by residents and contaminates the recyclable material, reducing its marketability. Hence, in many cities and councils in Germany, for example, the residents are supplied with a grey 240 l bin for residual waste, a brown 120 l or 240 l "Compostainer" for the

6 collection of biodegradable waste, a 240 litre blue bin for paper and a 240 litre yellow bin for lightweight packagings. These bins are emptied on an alternating collection cycles, which results in considerable cost savings. In addition to these household bins, bank type containers/depot containers for glass can be sited at central locations. Thus a recycling quota of more than 70 % may be achieved. Alternating Collection Cycle in Germany l Grey Bin (Residual Waste) 4 weeks l Blue Bin (Paper/Cardboard) l Yellow Bin (Plastics / Packaging) 4 weeks 4 weeks l Intensively ventilated brown Bin (bio) 2 weeks l Depot Containers (Glass) 2-4 weeks Residual Waste Waste Paper Plastics, Packaging Organic Waste This flexible system offering various bin and container capacities can be used in both rural and densly populated urban areas of big cities. Regional structure and population density

7 are very important parameters for a waste management system, since the proportion of the material fractions vary from one area to the other. From practical operation all over the world we know that both big cities and small councils have achieved excellent results with the Schäfer collection systems. In our experience an effective information campaign and a partnership between the waste management organizations and the residents in making clear the need for reduction result in a high degree of public acceptance and active participation. This acceptance and active cooperation of the residents are usually much higher than expected by our local politicians. This is the reason why in most cases we started introducing the system on a trial basis. But positive public response and the decision to continue the system follow quickly after only a very short time. Separate collection at source only makes sense if the reclaimed materials can be effectively fed back into the economy, i. e. if there is a market for these reusable materials. We know that the industry is technically able to run production with increased use of reclaimed materials, such as waste paper or glass, and thus to create a market for them. Up to now there have been no marketing problems with metals and textiles. New technologies and methods have been developed for the effective recycling of postconsumer plastics. In agriculture and horticulture, for cemetries and public parks etc. there is a big demand for soil improvers/compost. Besides, the use of compost helps to reduce the exploitation of peat soil and thus keeps the destruction of upland moors to a minimum. For ecological reasons, and also because the organic fraction is the largest component of the domestic waste volume, the separate collection of this material and its subsequent composting is being implemented in many European countries. In Germany, for example, 10 m tonnes of organic waste p. a. are collected separately. Experience and case studies have shown that it is possible to reduce the waste volume by more than 50 %.

8 Even if there is sufficient landfill space available, it does not mean that natural resources are too. Recycling does not only reduce the waste volume, but also helps to conserve natural resources. At current rates of consumption some of us will be able to watch certain natural resources being exhausted, like oil or gas. The significance of recycling becomes clear, when you consider that for example one tonne of recycled paper saves 1,700 kgs of timber and 109,000 litres of water. Besides, recycling paper consumes 61 % less water and 70 % less energy than using natural resources. Resource depletion, however, is only one problem we are facing, the other is environmental pollution. According to scientific estimates landfills have a potential to produce leachate contaminating the groundwater and methane gas contributing to the stratospheric ozone depletion for as long as 100 years. If one considers all these effects which untreated waste materials potentially have on our environment and health, does it then not seem to be very irresponsible to doubt the economic sense of recycling, not to act due to the apparent lack of markets for the material, just to fulfill the Government target of recycling a certain percentage of the total waste stream and to landfill or incinerate the remaining recyclables including organic materials with a clear conscience? Certainly, the avoidance of waste has top priority, but since this does not result in any significant reduction of the waste volume, we have to focus on the separate collection and recycling and keep landfilling and incineration to a minimum. References

9 Federation of the German Waste, Water and Raw Materials Management Industry, Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Umweltbundesamt: Study on Recycling stops greenhouse gases