Developing an Organics Management Program

Transcription

1 Developing an Organics Management Program Presented by Konrad Fichtner, P. Eng. Compost Council of Canada Workshop Vancouver, BC February 8, 2011

2 Where does Organics Management Fit in? Recycling Organic Treatment Thermal Treatment Landfill Landfill 2/14/11 Page 2

3 Getting the Ball Rolling You have decided to expand your diversion programs Organics have been selected as the low hanging fruit Composting, anaerobic digestion (AD) or both are being considered What is the process going forward? 2/14/11 Page 3

4 What Is Our Feedstock? Which organics to extract? From what sources and how much? How to collect? How much are we going to get of what? You can t think about technology until you know what you have. 2/14/11 Page 4

5 Which Organics to Extract? Organics are the largest portion of the residual waste stream Yard and garden Kitchen Contaminated paper Clean wood Biosolids Which are left to collect? Which are already managed/diverted? 2/14/11 Page 5

6 Sources of Organics Residential waste stream Kitchen scraps Yard and garden ICI Multi-family Restaurants Grocery stores Food processing Other WWTP Biosolids? 2/14/11 Page 6

7 Residual Waste Stream Sources DLC 37% Residential 21% ICI 42% 2/14/11 Page 7

8 Organics in the Waste Stream 2/14/11 Page 8

9 Collection Options Residential Residential collection Determine frequency of collection Select types of containers Consider automated or semi-automated collection vehicles Organics are heavy Look at split packer trucks to reduce truck traffic and emissions If collection is contracted out Allow haulers to bid on collection of recyclables, waste and organics in one contract 2/14/11 Page 9

10 Example of Efficient Collection Arrangement 2/14/11 Page 10

11 Collection Options ICI - Multifamily Considerable planning and consultation needed Extra space required for additional bins Staff training needed Education for multi family residents Hygiene issues Contract changes or new contracts with haulers Are transfer stations or modification to transfer stations needed? How to motivate ICI to participate? 2/14/11 Page 11

12 Technology Selection Technology depends on type and volume of organics Food waste usually requires in-vessel composting or AD Yard and garden materials can be windrowed Yard and garden may be needed as amendment for food organics Seasonal variation needs to be considered Technology also depends on location Sensitivity of local receptors to odours Availability of land Markets for end product are very important. Overall economics are vital 2/14/11 Page 12

13 Technology Options Composting Anaerobic Digestion (AD) Usually followed by composting of digestate Alternative, emerging Torrefaction Conversion to liquid fuels 2/14/11 Page 13

14 Composting Process Organics separated from waste stream Carbon/ nitrogen levels adjusted Moisture level and particle size adjusted Material piled or loaded into containers Ongoing aeration Decomposition occurs

15 Composting Technologies Static piles (not suitable for SSO) Turned windrows (less suitable for SSO) Aerated static piles Covered aerated static piles In-vessel systems: Bays, beds and tunnels Containerized systems 2/14/11 Page 15

16 Turned Windrows

17 Covered Aerated Static Pile (GORE)

18 Covered Aerated Static Pile (Ag-Bag)

19 In-Vessel Technology Examples Right: Edmonton Compost Facility, aeration hall Left: Transform Compost System

20 In-Vessel Technology Examples Below: Wright compost system Above: Modular container composting

21 In-Vessel Technology Examples (Christiansen)

22 In-Vessel Technology Examples Right: ICC Left: HotRot

23 Anaerobic Digestion Converts organic matter into biogas, which is 50~60% methane More complex than composting Best for well segregated organics (common for biosolids, manures) Solid residue (digestate) requires composting Generally more expensive than composting per tonne of waste, but recovery of some energy Smaller footprint than composting 2/14/11 Page 23

24 Anaerobic Process Organics separated from waste stream Pulping and decontamination of feedstock Material fed into reactor Biogas recovered from reactor Digestate removed from reactor Energy recovery Liquid fraction recycled Solids dewatered Aerobic composting

25 Different Types of Anaerobic Digestion Mesophilic Reactor at 37-41oC Longer residence time in reactor (larger footprint) More stable system Thermophilic Reactor at 50-55oC Gas production is faster Greater pathogen reduction Class A biosolids More energy intensive (net basis)

26 Different Types of Anaerobic Digestion Wet Requires hydropulping Good removal of plastic contaminants Contaminants in reactor cause problems Dry Uses less energy and water Contaminants in reactor are not as problematic

27 Different Types of Anaerobic Digestion One Stage Longer track record One reactor Simpler design/construction Two (Multi) Stage 2 or more reactors (specialized for acid phase and methane phase) More robust

28 Typical Kitchen Scraps as Collected 2/14/11 Page 28

29 Tipping Floor at Organics Facility 2/14/11 Page 29

30 Grit Removal and Hydropulper (BTA wet system) 2/14/11 Page 30

31 Anaerobic Digestion Hydropulper at BTA facility in Newmarket, Ontario Mesophilic digester at BTA facility in Newmarket, Ontario

32 Other technologies Torrefaction Low temperature roasting of organics to create bio-coal Can be used to replace fossil coal in cement kilns and power plants Early development stages No commercial facilities in North America Good promise for future where renewable energy has priority Liquid fuels Conversion to gas (type of gasification) Conversion of gas to liquid fuels Chemistry is known Practical applications are being tested 2/14/11 Page 32

33 Technology Selection Deciding factors: Costs versus revenues Location and size of site Local energy policy GHG credits available Maturity of technology 2/14/11 Page 33

34 How to Make the Selection Engineering study Local, or Regional Private sector competition Requires precise request for proposal Vendors need accurate data to work with Be prepared to commit feedstock supply for the long term Make specification performance based Environmental Financial Social Consider P3 2/14/11 Page 34

35 Conduct Basic Research and Studies Market study Project volume of organics Quality and categories of organics Determine where feedstock would come from What can be guaranteed to a proponent? Conduct preliminary feasibility Avoid cost surprises when proposals received Better knowledge, better bargaining power What services can the municipality offer: Site? Product sales? Permitting assistance? 2/14/11 Page 35

36 Costs Capital costs vary widely depending on selected technology Open air composting lowest cost option In vessel composting and AD have similar costs Expect range from $60 to $600 per tonne of installed annual capacity Operating costs for compost systems range from $20 to $60 per tonne. AD systems generally cost more to operate, but also have extra revenue from energy sales. Little North American data, only two plants in Canada Factor in additional collection costs 2/14/11 Page 36

37 Facility Ownership Municipality, or regional district owned Hi degree of control over feedstock, technology and cost Privately owned? Privately owned facilities will require long term contracts for organic feedstock Public Private Partnership? Depends on degree of control desired and available funding 2/14/11 Page 37

38 REALITY CHECK Can we afford this? Are we saving money or adding a financial burden? Include savings from lower landfill and waste to energy costs Will our residents and business pay? How much waste are we diverting from landfill and what is the net cost per tonne? How much CO2 are we avoiding? 2/14/11 Page 38

39 Enabling Legislation Feedstock supply to organic system operators must be ensured Some regions ban certain organic wastes to force it into composting Collection contracts may require materials to be taken to a certain facility Flow control is theoretically possible, but may be challenged in the courts 2/14/11 Page 39

40 Final Analysis the Triple Bottom Line What are the economic benefits/costs of the proposed initiative? Landfill space saved Revenues vs. costs Impact on tipping fee What are the environmental benefits? Additional source of renewable energy Reduced landfill leachate and gas GHG sequestration or avoidance Soil amendment What are the social benefits? Jobs Reduced trucking and landfilling 2/14/11 Page 40

41 Thank You