Carbon storage in engineered wood products in landfills

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Claire Harrell
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1 Carbon storage in engineered wood products in landfills Presented by Fabiano Ximenes, NSW DPI, 2013

2 Talk Outline - Background to project - Landfills in Australia - Excavations - Experimental work - Implications to industry

3 Project background - Previous projects: long-term C storage in solid wood -Funding: FWPA / Laminex / DAFF 1) Long-term C storage in engineered wood products and paper from landfills; 2) Long-term C storage in engineered wood products and paper in anaerobic reactors in the laboratory

4 Why is it important? - Greenhouse credentials of wood products (Carbon trading) - Life Cycle Assessments - More accurate estimates of national greenhouse emissions

5 Landfill types Municipal solid waste landfills C&D landfills C&I landfills Bioereactor landfills

Landfills Past: shallow, no compaction, aerobic Sanitary landfills: 20-30 s

6 Landfills Past: shallow, no compaction, aerobic Sanitary landfills: s Engineered landfills: s Modern landfills: large, deep, compaction, anaerobic

7 Landfills

8 Wood waste disposal Current options: Recycle/reuse; landfill Wood waste to landfills in Australia: Mt / year; paper : 1.3 Mt / year Eventually most recycled products either decay or placed in landfills Alternative: Incineration for energy recovery (Europe model) *Fossil-fuel displacement benefits

9 Decomposition in landfills Decay of organics: 50:50 CO 2 and CH 4 Oxidation factor: 0.1 (default) probably higher Best-practice landfills: 75-90% CH 4 recovery Methane generation: 0-30 years

10 Decay of wood in landfills Wood is made up primarily of cellulose, hemicellulose and lignin Wood type Cellulose (%) Hemicellulose (%) Lignin (%) Softwood Hardwood

11 Decay of wood in landfills Wood is made up primarily of cellulose, hemicellulose and lignin Lignin is degraded under aerobic conditions

12 Wood degradation (Aerobic) Undegraded wood Bacterial attack Severe fungal attack From: MSc thesis: Preservation of wood using oxy-aluminium compounds. Ximenes 2000

13 Decay of wood in landfills Wood is made up primarily of cellulose, hemicellulose and lignin Lignin is degraded under aerobic conditions If landfill is under anaerobic conditions, then lignin (and some of the cellulose and hemicellulose) will not degrade

14 Methodology - Excavations Identification of sites (worst case scenario) Site characterization Target products Chemical composition: Cellulose / Hemicellulose / Lignin / Ash Comparison with matching controls

15 To understand garbage you have to touch it, to feel it, to sort it, to smell it Rathje and Murphy, 2001 Excavation at Lucas Heights

16 Excavation at Meadowbank

17 20 years in landfill

18 29 years in landfill

19 46 years in landfill

20 44 years in landfill

21 Ximenes et al 2008 Analysed range of solid wood samples from two landfills in Sydney No significant loss of carbon in one landfill (samples buried for years) Approx. 18% loss of carbon from samples buried in another landfill (46 years)

5 m in depth) The ph ranged from 5.6 to 7.4.

22 Cairns - Portsmith Sampling (0.5 m intervals), until the bottom of the cells ( m in depth) The ph ranged from 5.6 to 7.4. The temperature of the waste was slightly higher than the ambient temperature Samples buried for years

23 Brisbane - Fitzgibbon Sampling (0.5 m intervals), until the bottom of the cells ( m in depth). The ph ranged from 6.4 to 6.8. The temperature of the waste was slightly higher than the ambient temperature. Samples buried for 18 years

24 Brisbane - Fitzgibbon Table 1. Mean ph and temperature of waste buried at Roghan Rd. landfill Cell Depth of cell (m) ph (Mean, SD) Temperature ( C; Mean, SD) (0.3) 25.8 (0.4) (1.0) 26.4 (0.6) (0.3) 27.0 (2.0) (0.2) 25.4 (0.8) Combined 6.7 (0.6) 26.2 (1.3)

25 Brandown (Kemps Creek) Sampling (0.5 m intervals), until the bottom of the cells (7.0 m in depth). The ph ranged from 6.8 to 7.0. The temperature of the waste increased slightly with depth. Samples buried for years

Depth of cell (m) ph (Mean, SD) Temperature ( C; Mean, SD) 1 7.0 7.

26 Brandown (Kemps Creek) Table 2. Mean ph and temperature of waste buried at Brandown landfill Cell Depth of cell (m) ph (Mean, SD) Temperature ( C; Mean, SD) (0.5) 23.6 (3.8) (0.2) 20.5 (0.5) (0.7) 22.3 (3.1) Combined 7.0 (0.7) 22.7 (3.3)

27 To understand garbage you have to touch it, to feel it, to sort it, to smell it Rathje and Murphy, 2001 Excavation in Brisbane

28 Excavation in Brisbane

29 Excavation in Kemps Creek

30 Excavation in Kemps Creek

31 16 years in landfill

35 18 years in landfill

36 14 years in landfill 14 years in landfill

37 Plywood - Cairns

38 Brisbane Kemps Creek

39 Brisbane Cairns

40 Kemps Creek

41 Brisbane Cairns

42 Kemps Creek

43 Excavations Moisture content Table. Moisture content of engineered wood products recovered from Sydney, Brisbane and Cairns according to product type Site Moisture content (%) Mean (SD, N) Particleboard MDF Plywood / Veneer Kemps Creek 37 (8.8, 29) 44.7 (10.0, 19) 38.9 (10.1, 12) Brisbane 45 (10.0, 21) 47.9 (9.7,20) 41.4 (10.0,10) Cairns (4.2, 6) 56.9 (3.0, 4)

44 Excavation Fibre analysis Table. Chemical composition analysis of engineered wood product samples recovered from Portsmith landfill, Cairns. Ash Normalised Composite wood (%, SD) product type N Sample type Holocel. Lignin MDF 9 Landfill 62.2 (1.7) 37.8 (1.7) 4.8 (1.5) 1 Control Plywood 8 Landfill 59.4 (6.9) 40.6 (6.9) 5.3 (3.3) 1 Control Particleboard 2 Landfill Control * Standard deviation provided for landfill engineered wood product types with at least 3 samples. Range provided for landfill engineered wood product types with 2 samples only

45 Excavation Fibre analysis Table. Chemical composition analysis of engineered wood product samples recovered from Roghan Rd. landfill, Brisbane. Normalised Composite wood product type N Sample type Holocel. Lignin Ash (%,SD) MDF 21 Landfill 65 (1.7) 35 (1.7) 6.8 (5.4) 1 Control Particleboard 25 Landfill 64.1 (4.7) 35.9 (4.7) 9.4 (9.2) 4 Control 66.9 (0.3) 33.1 (0.3) 0.5 (0.01) Plywood 5 Landfill 62.9 (5.0) 37.1 (5.0) 4.1 (2.3) 1 Control Veneer 6 Landfill 63.4 (5.4) 36.6 (5.4) 4.6 (1.8) 1 Control * Standard deviation provided for landfill engineered wood product types with at least 3 samples.

46 Excavation Fibre analysis Table. Chemical composition analysis of engineered wood product samples recovered from Brandown landfill, Sydney. Normalised Ash Composite wood Sample (%,SD) product type N type Holocel. Lignin MDF 19 Landfill 63.4 (4.8) 36.6 (4.8) 4.1 (3.2) 1 Control Particleboard 28 Landfill 64.6 (2.4) 35.4 (2.4) 5.1 (6.7) 4 Control 66.9 (0.3) 33.1 (0.3) 0.5 (0.01) Veneer 6 Landfill 64.9 (1.5) 35.1 (1.5) 5.0 (2.3) 1 Control * Standard deviation provided for landfill engineered wood product types with at least 3 samples.

47 Results - Excavation Table. Carbon storage in engineered wood products recovered from MSW landfills in Cairns and Brisbane, and engineered wood products recovered from a C&D landfill in Sydney Carbon storage (%) Product type Cairns Sydney Brisbane MDF Particleboard Plywood 90.6 NA 99.5 Veneer NA

Excavation - issues Possibility of decay while the products where in service (before disposal); Possibility of decay taking place in the aerobic stages of the landfill life; Possibility of loss of

48 Excavation - issues Possibility of decay while the products where in service (before disposal); Possibility of decay taking place in the aerobic stages of the landfill life; Possibility of loss of carbon due to decay of a chemical nature in landfills; Difficulties in finding suitable controls for comparisons with landfill samples Difficulties in finding enough controls to enable meaningful statistical comparisons

49 Lab-Scale Reactors To determine carbon storage / loss for products under controlled, optimised anaerobic decay conditions Products included (Laminex): Particleboard (Trade Essentials): 1.8 kg MDF (Trade Essentials Craftwood): 1.8 kg HPL (Laminex Redback): 2.2 kg

50 Methodology - Laboratory Reactors filled with composite wood products and seed material (anaerobic conditions) Moisture, temperature, ph, nutrients optimum Monitoring release of CH 4 and CO 2 (gas chromatography) Mass balance after gas release is finished Carbon storage / loss determined

(Veolia bioreactor landfill, Goulburn) Regular monitoring of

51 Lab-Scale Reactors Conditions to maximize decomposition Temperature: 39 C Leachate neutralization and recirculation (Veolia bioreactor landfill, Goulburn) Regular monitoring of nutrients: target concentrations NH 3 -N: 100 mg of N/L PO 4 -P: 5-10 mg of P/L

52 Lab-Scale Reactors

53 Particleboard / MDF samples: before and after Particleboard MDF

54 Results - Laboratory ph

55 Results - Laboratory Reactor 1 Gas Composition Particleboard Reactor 2

56 Results - Laboratory Reactor 3 Gas Composition MDF Reactor 4

57 Results - Laboratory Table. Carbon storage and carbon loss (range) from engineered wood products in bioreactors Product type Carbon storage (%) Carbon loss (%) Particleboard MDF High-pressure laminate 100 0

58 Research Outputs: Summary Field - High levels of C storage in engineered wood products after up to 20 years Lab - 0% carbon loss from MDF and particleboard * * Results confirmed in an independent study in the US (Wang et al 2011)

59 Carbon Storage in Australia's Forest Plantations, Wood Products in Service and in Landfill Mt C 88 Mt C 94.6 Mt C Plantations Wood in service Wood in landfills

60 Implications for Industry cont. - Demonstration of long-term carbon storage: carbon credits * Additional carbon revenue (additional carbon to trade) * Increasing value of thinnings / incentive for plantation expansion MORE $ FOR C

61 Implications for Industry - Use of engineered wood products has a significant beneficial GHG impact - Any of the current end-of-life options: Recycling Energy Landfill POSITIVE GHG OUTCOME

62 Implications for Industry - Improved outcomes in LCAs of engineered wood products - Improved outcomes in building rating schemes WOOD PRODUCTS MORE COMPETITIVE IN BUILDING RATING SCHEMES

63 Summary - Excavations of engineered wood products in a range of climatic zones: high C storage after up to 18 years - Laboratory reactors: no C loss under controlled, optimised, anaerobic decay conditions - Engineered wood products in Australia: longterm storage of C

64 Wang et al 2011 Aim: characterize the anaerobic biodegradability of major wood products in municipal waste in the USA Experimental set-up: 8 L bioreactors Carbon loss from solid wood: 0 7.8% Carbon loss from Particleboard, MDF and plywood: %

65 Current work - Consolidation of data from more recent excavations - Consolidation of data from experimental work in the US (paper products) and in Australia (paper products and composite wood products) - Bioreactor experiments with range of Australian solid wood types ongoing

66 Key references Ximenes, F.A.; Gardner, W.D.; Cowie, A. The decomposition of wood products in landfills in Sydney, Australia. Waste Manag. 2008, 28, Wang, X.; Padgett, J.M.; De la Cruz, F.B.; Barlaz, M.A. Wood biodegradation in laboratory scale landfills. Environ. Sci. Technol. 2011, 45,

67 THANK YOU!

Carbon Storage in Engineered Wood Products in Landfills

` PROCESSING PROJECT NUMBER: PRB180-0910 SEPTEMBER 2013 Carbon Storage in Engineered Wood Products in Landfills This report can also be viewed on the FWPA website www.fwpa.com.au FWPA Level 4, 10-16 Queen