the region of halton biosolids management into the future
DESCRIPTION
The Region of Halton Biosolids Management into the Future. Regional Municipality of Halton Ontario, Canada. Current Status. Ability to remove solids from WWTP’s “on demand” is critical to maintain effluent quality Production in 2001 318,848 m 3 liquid biosolids - PowerPoint PPT PresentationTRANSCRIPT
The Region of HaltonThe Region of Halton
Biosolids Management into the Biosolids Management into the FutureFuture
Regional Municipality of HaltonOntario, Canada
Current StatusCurrent Status• Ability to remove solids from WWTP’s “on demand” is critical to maintain effluent quality• Production in 2001
• 318,848 m3 liquid biosolids• 8,216 m3 dewatered cake
• Liquid biosolids applied to land within Halton• Dewatered cake stored and applied to land within and outside Halton• Program operations under contract by Terractec Environmental Ltd.
Limitations of Current StrategyLimitations of Current Strategy• Insufficient land within Halton to apply 100% of biosolids currently produced• Available agricultural land expected to decrease marginally in the future• Biosolids quantities estimated to increase by 60% over next 20 years• Storage time at BMC estimated to decrease to less than regulation minimum 6 months by 2008• Inability to access farmland during wet weather can result in inadequate storage at the BMC
Biosolids Projections
0
50000
100000
150000
200000
250000
Pro
ject
ed B
ioso
lid
s P
rod
uct
ion
(m3 /y
)
20012021
Acton
Georgetown
Milton
Mid-Halton
Oak SW
Oak SE
Skyway
Required vs. Available Land
0
500
1000
1500
2000
2500
3000
2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
Year
Land
(ha)
Available land in Halton
Land required for liquid biosolids (excluding Skyway)
Total land required for liquid + Skyway cake
Considerations for Future BiosolidsConsiderations for Future Biosolids ManagementManagement
• Continue land application to the extent that can be supported by land within the Region
• highly successful program• continuing demand from farmers• Regional investment in infrastructure
• Diversify biosolids management program to include one of the following options:
• non-competing nutrient end use• non-nutrient end use
Non-Competing Nutrient End UseNon-Competing Nutrient End Use• Ontario Compost Guidelines – compost from biosolids does not meet criteria for unrestricted utilization – not an option• MOEE/OMAF Guidelines – pathogen free biosolids (US EPA Class A) not recognized at this time, crop restrictions in Ontario – not an option• Ag Canada Fertilizer Act – biosolids marketed as fertilizer under the Act must meet certain requirements including metal content but no site or crop restrictions – potential option
Non-Competing Nutrient End Use Non-Competing Nutrient End Use (cont’d)(cont’d)
• Halton biosolids meet metal requirements in Agriculture Canada Fertilizer Act and US EPA limits for “Exceptional Quality” biosolids• Alkaline stabilization and drying/pelletization are producing products in Ontario that are being marketed, under the Fertilizer Act, for higher value end uses
Non-Nutrient End UseNon-Nutrient End Use
• Thermal destruction of organic material leaving inert ash for disposal• Potential energy recovery from combustion of the organics in biosolids• Fluidized bed combustion considered state-of-the-art incineration technology based on:
• energy efficiency• air emission control
Existing Management Options
Biosolids Management Centre Storage Liquid to LandDigested Biosolids
Mobile Dewatering
Dewatering Cake to Land
Cake to Halton Landfill
Cake to Private Landfill
Diversification Options
Contingency
Diversification OptionsDewatered Cake
Temporary Storage
Incineration Ash to Landfill
Alkaline Stabilization Product to Market
Land Application Landfill Cover Disposal in Landfill
Thermal Drying Product to Market
Land Application Landfill Cover Disposal in Landfill
Contingency
Contingency
Alkaline StabilizationAlkaline Stabilization
• Beneficial use option• Inactivation of pathogens to produce Class “A” biosolids
• addition of alkaline mixture such as lime or cement kiln dust• elevate pH > 12 for 72 hours• maintain temperature > 52oC for 12 hours• dry to > 50% solids
Alkaline Stabilization (cont’d)Alkaline Stabilization (cont’d)
• Product • fertilizer value• acts as liming agent for low pH soil • improves soil structure
• No site or crop restrictions on use• Operating facilities approved in Ontario• Product marketed under Fertilizer Act• Experience with marketing product in Ontario
Thermal Drying/PelletizationThermal Drying/Pelletization
• Beneficial use option• Inactivation of pathogens to produce Class “A” biosolids
• temperature of biosolids > 80oC• moisture reduced to < 10%
• Product• used directly as a fertilizer• component for the manufacture of commercial fertilizer
Thermal Drying/Pelletization (cont’d)Thermal Drying/Pelletization (cont’d)
• No site or crop restrictions on use• Operating facilities approved in Ontario• Product marketed under Fertilizer Act• Experience with marketing product in Ontario
IncinerationIncineration
• Complete destruction of pathogens, viruses and organics
• high temperature combustion >800ºC• Heat recovery possible for in-plant use• Autogenous combustion at 28% solids
• no additional fuel required• Majority of metals immobilized in ash• Minimal volume of residue for ultimate disposal• Can meet stringent air emission criteria
Sites Visited by Halton Team
• Incineration– London
• Alkaline Stabilization– Sarnia– Leamington– Syracuse
• Drying/pelletization– Windsor– Smiths Falls– Toronto
Technology Rating CriteriaEnvironmental Sustainability Reliability Cost
Odours Changes in legislation
Proven technology
Capital
Air emissions Public opinion Complexity O&M
Surface/ground water
Ability to expand
Dependence on weather
Soil Competition Waste on demand
Public exposure Contingency
Ease of permitting
Rating of Acceptable Technologies
Incineration Alkaline Stabilization
Thermal Drying
Environmental 2.5 2.83 2.83
Sustainability 1.5 2.25 1.75
Reliability 2.6 2.8 2.6
Cost 2 2.5 2.5
Total Score 8.6 10.38 9.68
Preliminary Identification of Preliminary Identification of Recommended SolutionRecommended Solution
Diversify Halton’s biosolids management program to address land availability limitations by:• Building an alkaline stabilization facility to process the excess biosolids • Developing a program to market the resulting product to end users outside the existing land application program
Implementation PlanImplementation Plan• Public consultation process to present recommended solution to public and seek input• Confirm preferred solution• Submit “Notice of Completion” to review agencies and public• Submit recommendation to Council for approval• Select site for facility• Complete pre-engineering and tender documents• Call for tenders on the project• Award contract• Initiate construction