Anaerobic digestion of slaughterhouse waste in Sweden Åke Nordberg JTI - Swedish Institute of Agricultural and Environmental Engineering

Anaerobic digestion of animal by-products: a sustainable treatment alternative Biogas

Presentation out-line Regulations for anaerobic digestion (AD) of animal by-products (ABP) Potential biogas substrates from slaughtered animals AD of slaughterhouse waste in Sweden

Regulation (EC) No 1774/2002, applicable from 1st of May 2003 in all member states Category Material Category 1 Specified Risk Material representing an increased risk for public health, animals and environment. Not designated for AD Category 2 – without preliminary treatment Manure, digestive tract content, milk, colostrum Category 2 – after sterilisation with steam pressure and marking (with smell) Fallen animals, slaughtered but not intended for human consumption (everything not included in Category 1 and 3) Category 3 – approved according to Article 15 (pasteurisation) Material originating from animals fit for slaughter but not intended for human consumption. ABP from food production Category 3 – approved according to national legislation Catering waste (except from international transport)

Pig slaughtering facility Manure Cat. 2 – no required treatment Anaerobic Digester (According to article 15) Digestive tract content Digestive tract Cat. 3 - pasteurisation Pasteurisation <12 mm ≥60 min ≥70 °C Bones, slaughter by-products Parts of slaughtered animals Blood Sterilisation ≥ 133 °C ≥ 3 bar ≥ 20 min Cat. 2 - sterilisation Fallen animals Screenings and flotation sludge >6 mm (< 6 mm not covered by ABP-regulation) End product Salmonella: 0 CFU in 25 g (5 samples) Enterobacteriaceae: 3 samples < 10 CFU/g, 2 samples < 300 CFU/g Placing on the market, trade, application to land (not pasture)

Bovine slaughtering facility Manure Cat. 2 – no required treatment Anaerobic Digester (According to article 15) Rumen content Rumen Cat. 3 - pasteurisation Pasteurisation <12 mm ≥60 min ≥70 °C Bones, slaughter by-products Parts of slaughtered animals Blood* (no SRM in blood stream) SRM; vertebral column and skull, intestines Sterilisation/ Incineration Not intended for AD Cat. 1 Screenings and flotation sludge >6 mm End product Salmonella: 0 CFU in 25 g (5 samples) Enterobacteriaceae: 3 samples < 10 CFU/g, 2 samples < 300 CFU/g Placing on the market, trade, application to land (not pasture) (< 6 mm not covered by ABP-regulation)

Calculated methane potential from slaughter of cattle and pigs divided into different waste categories (% of total methane potential) and the total amount (MJ or kWh per animal). Rumen, stomach and intestinal content (Cat. 2) Cat. 3 (excl. blood) Blood (cat. 3) Cat. 2 Cat. 1 (SRM) Total % of tot MJ/ animal kWh/ Cattle 9 62 5 3 21 1300 361 Pig 6 82 8 4 - 140 39

Potential value of gas and organic fertiliser from slaughterhouse Euro/ton Fertiliser Meat and bone fraction 65 18 Blood 10 4 Digestive tract +content 11 2 Sludge 22 5 Raw biogas: 3.3 Eurocent/kWh N: 0.76 Euro/kg P: 1.20 Euro/kg K: 0.33 Euro/kg

Slaughterhouse waste in Sweden- legislation background 1988 (SFS 1988:537) Meat meal from carcasses not allowed in animal fodder 1991 (LSFS 1990:51) Use of low-risk animal by-products in ruminant fodder prohibited in 1991

Existing biogas plants approved for ABP co-digestion Luleå Skövde Borås

Swedish co-digestion plants treating animal by-products Temperature Digestate Gas utilisation Helsingborg Mesophilic Slurry organic fertiliser Heat, electricity, vehicle fuel Kalmar Thermophilic Vehicle fuel Kristianstad Heat, vehicle fuel Laholm Upgraded gas to grid Linköping Uppsala Vänersborg Solid digestate Skövde Borås Luleå Heat, electricity

Summary of capacity and treated waste in Swedish biogas plants* 2003 Treatment capacity 300 000 m3 100 % Used capacity 220 000 m3 73 % Planned increase of treatment capacity 125 000 m3 +42 % Manure 68 000 m3 30% Source-sorted household waste 12 000 m3 5 % Source-sorted from restaurants, shops etc 2 200 m3 1 % Slaughterhouse waste 101 000 m3 45 % Waste from other food industry 27 000 m3 12 % Other organic waste 6 000 m3 3 % Water 7 500 m3 Total amount of substrate 223 700 m3 *10 ABP-approved biogas plants (Major part treated in 7 plants)

Concluding remarks Animal by-products are suitable for anaerobic digestion giving high gas yields and a nutrient rich organic fertilizer AD of slaughterhouse waste within the legislative framework 1774/2002 offers a safe and sustainable waste management solution Governmental subsidies for facilitating investments in AD of slaughterhouse waste is well invested money from a sustainable point of view