Introduction and organic waste situation

update July 2010

1 Biowaste production and treatment
Municipal solid waste
In the year 2008, a total of 5.65 Mio t of urban waste were collected in Switzerland (652 kg per capita). This figure does not include either construction waste, or industrial waste, or sewage sludge (see below).

Table 1. Municipal solid waste in Switzerland (2008)

Some 2.83 Mio t. of MSW were incinerated while less than 2,000 t were directly landfilled.
Separately collected biowaste amounted to 930,000 t or 16.5% of the total.
In 2001 and 2002, a study of the composition of unsorted municipal waste was conducted in 33 localities of different size and characteristics, representing some 750,000 inhabitants (10% of the Swiss population) . The result of this analysis, which does not include bulky waste, is shown in fig 1.
Figure 1. Average composition of the unsorted MSW from 33 Swiss communities (2002)

It appears that 27% of the unsorted municipal waste is biologically treatable, not including paper and cardboard. Extrapolating this result, one can assume that approximately 450,000 t/a of biowaste are still available in MSW for diversion.

Sewage sludge
An estimate of 0.210 Mio t (dry matter) of digested sewage sludge are produced each year in Switzerland. This sludge has been digested or stabilised at the sewage treatment plants themselves, losing some 20 to 30% of its weight.

There is one main disposal channel: incineration. Landfilling of sludge has been banned since the 1 January 2000. The use of sludge in agriculture has been questioned, in particular because of the inorganic and organic pollutants, including traces of drugs and hormones. The demand for sewage sludge as fertiliser has thus steadily decreased, all the more since a potential risk of contamination with BSE has been shown to exist, due to the wastewater from slaughterhouses. Even though the strict security measures that have been enforced, i.e. the separation of solids from the wastewater flow, render this risk negligible, the principal distributors have banned the use of sewage sludge for the production of their labeled meat and dairy products. Organic farming has long banned the use of sewage sludge. The use of sewage sludge in agriculture is banned in Switzerland. In the mean term all sewage sludge will have to be incinerated.

Table 2. Amounts of sewage sludge produced and disposal routes

In 2008, 210,000 tonnes of digested sewage sludge (dry matter) were produced in Switzerland. Only about 1% of the total were disposed of in agriculture in 2008.

Other biowaste
An estimated 45,000 t/a of industrial and commercial wastes are co-digested in agricultural biogas plants, while some 20,000 t/a of industrial and catering wastes are co-digested with sewage sludge in wastewater treatment plants.

2 Legal framework for the biowaste stream

The constitutional article relating to the protection of the environment was accepted by popular vote in 1971 (Article 24, para. 7). This article states that the Confederation must legislate to prevent damage or nuisance to mankind or the natural environment.

This constitutional basis was then translated into the Environmental Protection Act (Umweltschutzgesetz, USG), which came into force in 1984. Among its basic principles, this law introduces the "polluter pays principle", and that of limiting nuisances at the source. It is essentially a framework, which requires specific implementation ordinances relating to each of the dispositions it contains.
The relevant principles and goals of the federal government pertaining to waste management were laid down in the Guidelines on Swiss Waste Management (1986) and in the Waste Concept for Switzerland (1992):

Waste should as far as possible be avoided at source. This can be achieved by means of low-waste production methods, the production of long-life goods and the optimization of packaging.

Both in manufacturing processes and in products, pollutants are to be avoided or reduced as far as possible, in order to facilitate subsequent waste treatment or recycling steps.

Waste is to be recycled wherever this appears to be environmentally beneficial and economically feasible.
Residual wastes are to be treated in an environmentally sound manner. In the long term, only materials of final storage quality should be disposed of in landfills.

The main ordinance pertaining to waste management is the "Ordinance on the Treatment of Waste" of December 10, 1990 (Technische Verordnung über Abfälle, TVA). Article 6 prescribes the separate collection of the recyclable fractions of MSW. Article 7 states that home composting must be encouraged by the cantonal authorities. Biowaste that cannot be privately disposed of must be collected separately and recycled in centralised facilities.

The TVA prescribes measures for the construction and operation of composting facilities that treat more than 100 t of compostable materials per year (Art. 43 to 45). These measures concern the protection of groundwater, the proper control of the materials accepted and the analysis of the quality of the compost produced (nutrients and content in heavy metals).

These guidelines and prescriptions have resulted in the development of incineration as the main treatment mode for MSW. Already in the ‘90s, Switzerland incinerated over 80% of its unsorted municipal waste. However, in parallel, high levels of separate collections for a large number of materials had also been reached, due to a long history of such collections, in particular for glass, paper and metals. Over 45% of municipal waste is now collected separately and recycled.

The 1996 revision of the TVA banned the landfilling of all combustible material after the 1 January 2000, i.e. MSW, construction waste or sewage sludge. The amount of urban waste going directly to landfill is negligible (less than 1%).
In Switzerland the recycling of a waste fraction must not only be proven to be environmentally beneficial to be implemented, it must also be economically sustainable. Advanced disposal fees have thus been introduced on many products (PET beverage containers, batteries, glass bottles, electrical and electronic appliances) to finance the collection and recycling schemes. This is not possible for biowaste however. Economic sustainability of biowaste treatment can only be achieved if a real market can develop for its products.

In consequence, efforts are at present directed towards changing the image of compost and digestate, from a waste product to a valuable resource. Encouraged by the federal authorities, the Association of Swiss Composting and Methanisation Plants (ASCP) has developed quality guidelines, an inspectorate and a label, aimed at guaranteeing high standards of quality, both for the process management and its products (see chap. 5).

Limit values

Heavy Metals, organic pollutants and impurities
The limit values for heavy metals are defined in the Ordinance on Chemical Risk Reduction (Chemikalien-Risikoreduktions-Verordnung, ChemRRV; RS 814.81 ). They are listed in Table 3.
Table 3. Heavy metal limit values for compost and digestate from biowaste (ChemRRV, Annex 2.6)

Table 4. The following guidelines apply to compost and digestates (ChemRRV, Annex 2.6)

Table 5. Limit values for impurities in compost (ChemRRV, Annex 2.6)

Sanitation
The sanitation requirements for compost and solid and liquid digestate are laid out in the FDEA Fertiliser Book Ordinance (Düngerbuchverordnung, DüBV; RS 916.171.1), which states in Annex 1, part 6, nos 2010, 2030 and 2040: the production and application of farm manure, compost and digestate (both solid and liquid) must ensure that no undesired organisms, such as pathogens or seeds of alien plants are propagated.

Table 6a. Sanitation requirements for compost (ASAP Quality guidelines)

Table 6b: Sanitation requirements for digestate from biowaste (ASAP guidelines)

Should a process not fulfill the abovementioned prescriptions, the effective sanitation and the sanitary innocuousness of the product must be proven in another way, in particular, by analogy with the German Biowaste Directive (BioAbfV, 2007, Anhang 2), by means of a procedure verification (determination of the minimal and average retention time) and a product verification (detection of indicator organisms, such as salmonella, Plasmodiophora Brassicae and tomato seeds and, in the case of compost Tobacco Mosaic Virus). If the results remain under certain defined limit values, than the process can be deemed to comply with the sanitation requirements.

Prescriptions relating to compost application
According to the Ordinance on Chemical Risk Reduction, annex 2.6, n° 3.2.2, the authorised quantity that can be used over a three-year period is a maximum of 25 tonnes per hectare for compost and digestates (in relation to dry matter) or 200m3 per hectare for pressing liquor, provided that these quantities do not exceed the nitrogen and phosphorus requirements of the plants. It is prohibited to use, over 10 years, more than 100 tonnes per hectare of compost and digestates (in relation to dry matter) as soil improvement agent or as substrates, for the protection of soils against erosion, for their re-cultivation or for artificial potting soil.

3 Origin of the biowaste
About 55% the biowaste treated in the large plants (> 100 t/yr) originated from public collections. One third is delivered by the private sector (mainly gardeners) and the remaining 16% came from the industry.

4 Treatment of biowaste
In 2008, most of the 930,000 t biowaste collected were treated by the over 100 large plants with capacities over 1,000 t/yr. About 40% were composted in open-air windrows, up by 50,000 t from 2006 (fig 3). 16% of the waste was treated in closed or covered plants, 7% by field-side composting. Some 35% were anaerobically digested, most in the existing Kompogas plants.
An estimated (not inventoried) 300,000 t of biowaste is treated by home or community composting, or in plants with a capacity below 100 t/yr.
Figure 3. Treatment of municipal biowaste in Switzerland (2006).

Sewage sludge is digested in some 290 wastewater treatment plants equipped for AD, generally with some form of energy recovery, 25 of these plants co-digest with other waste. Some 20 agricultural biogas plants also co-digest other biowaste.

Table 7. Recycling of biogenic waste (2006)

Source: FOEN
Mechanical Biological Treatment

There are no MBT plants in Switzerland.

5 Quality assurance system
5.1 Quality Guideline, 2010 edition. Link to the text of the Guideline (in German or French).
What does a quality guideline bring?
The biowaste treatment sector needs to have its products recognised and used in agriculture. Their application must also be encouraged and further developed in horticulture and greenhouses.

For a long time now great efforts have been made to produce good quality composts, and been met with increasing success. In order to better reflect this positive evolution, the biowaste treatment sector has now drawn up a new Quality Guideline, outlining the specifications to which such good quality products should conform in the future. This will provide security to the users of such products, ensuring that the positive properties they require are fully expressed and that harmful properties, such as weed seeds, phytopathogènes or insufficiently mature material, will be eliminated. Furthermore, the information concerning the various types of products will be clearer and more coherent throughout the sector, ensuring users pick the correct product for the application intended.

The information pertaining to the plant inspectorate is available on the website www.compospect.ch. The plant inspectorate audits just over 200 plants throughout Switzerland (table 6). About half of the cantons have signed an agreement to have all their plants inspected. Elsewhere in Switzerland the plants are audited on a voluntary basis. The nationwide scheme is an extension of the auditing concept developed by the canton of Zurich in the 1990s.
Table 8. Plants inspected in 2009, by type of process

5.2 Branch inspectorate of Swiss composting and AD plants

Main aspects of the branch inspectorate
Principles
- simple, efficient
- promotes the self-responsibility of the composting and AD plants
- must not unduly burden the composting and AD plants
Plant audit

Frequency: once a year.
Independance: the inspector commissioned by the ARGE is neutral and independent.

Data transmission: all the data pertaining to a plant are treated confidentially by the inspector. They may only be transmitted to the competent federal, cantonal and communal authorities or to the operator of the plant concerned. If the plant is audited on a voluntary basis, the plant operator decides individually whether the data are to be transmitted to the cantonal authorities. The inspector nevertheless has the right and the duty to signal any deficiency to the cantonal supervisory authority.

Under Art. 47 of the Environmental Protection Act, the competent authorities may publish the results of plant audits, after consulting the parties concerned, if these are of general interest. Trade and business secrecy must be preserved in all cases.

Inspection report: the inspector transmits his report to the cantonal authority, the plant inspected and if required to the communal authority.
Procedure if a deficiency is identified: the inspector signals any deficiencies to the cantonal authority in his audit reports. The cantonal authority decides on the remedial measures that must be taken.
Annual report: The results of all the inspections carried are synthesized in an annual report published by the ARGE.

6 Application and Markets
The processing of the 930,000 t of biowaste yielded some 500,000 t of compost and digestate in 2008. The outlet for about 70% of this amount is agriculture. Professional gardeners and substrate producers used 11%, and hobby gardening 6%.
Figure 4. Origin of the biowaste and use of compost in Switzerland (2008)

 

Fig. 5: Evolution of gate fee (CHF/t) and price of compost (CHF/m3) in the canton Zurich in from 1191 to 2009.

The gate fee (with 7.6% VAT) rose regularly until 2005, mostly because of investments for technical equipment including for anaerobic digestion, since then it has been decreasing. The price of compost for horticulture has not changed much, while the price in agriculture has become negative (costs for transport and spreading are not considered as composting costs). This shows some needs of future work to increase the value of the product in the eyes of the public and users.

7 Contacts and sources of country information
Federal Office for the Environment (FOEN), CH-3003 Bern: www.environment-switzerland.ch
FOEN, Raw Materials from Waste, environment magazine 3/09, www.environment.switzerland.ch/Mag2009-3
Swiss waste statistics (available in German or French): Hügi M., Gerber P. et al. 2008: Abfallwirtschaftsbericht 2008. Zahlen und Entwicklungen der schweizerischen Abfallwirtschaft 2005–2007. Umwelt-Zustand Nr. 0830, FOEN, Bern. 119 p, www.environment-switzerland.ch/uz-0830-d
www.environment-switzerland.ch/uz-0830-f
Swiss federal office of energy (SFOE), CH-3003 Bern: www.energie.ch / www.energieforschung.ch
VKS-ASIC-ASAP-ASCP (Association of Swiss Compost and Methanisation Plants): Verband Kompost- und Vergärwerke Schweiz, Oberdorfstrasse 40, CH-3053 Münchenbuchsee, tel. +41 31 858 22 24, fax. +41 31 858 22 21, info@kompostverband.ch, www.kompostverband.ch (in German and French)
KOMPOSTFORUM Schweiz, Paul Pfaffen, Zypressenstrasse 76, 8004 Zürich, tel. +41 43 205 28 82, fax +41 43 205 28 81, forum@kompost.ch, www.kompost.ch (in German)
BIOGAS FORUM: c/o Dr. A. Wellinger, Nova Energie GmbH, Châtelstrasse 21, CH-8355 Aadorf, arthur.wellinger@novaenergie.ch, www.biogas.ch (in German)
BiomassEnergie: Zollikerstrasse 65, CH-8702 Zollikon, biomasse@ebp.ch, tel. +41 44 395 11 11, fax +41 44 395 12 34,  www.biomassenergie.ch (in German and French)
Inspectorate: www.compospect.ch (in German and French)

Training: Educompost c/o UMWEKO GmbH, Weinbergstr. 46, 2540 Grenchen  +41 32 653 29 21 info@educompost.ch; www.educompost.ch (in German and French)

SAEFL 2004; A survey of the composition of household waste 2001/02. Environmental Series no. 356.Swiss Agency for the Environment, Forests and Landscape, Bern.

see English version on www.admin.ch/ch/e/rs/c814_81.html

Ordinance of 23 June 2004 on the Disposal of Animal By-Products (Verordnung vom 23. Juni 2004 über die Entsorgung von tierischen Nebenprodukten, RS 916.441.22)