Anaerobic Digestion and the Path Towards

Zero Waste

Paul RelisSenior Vice PresidentCR&R Incorporated

July 14,2009

The AD Context in California

In 2007 approximately 38 million tons of municipal solid waste (MSW) was disposed of in California landfills. (35 million tons as of 2008)

MSW landfills are the second largest anthropogenic source of methane and are an important source of greenhouse gas (CHG) emissions.

To an increasing extent landfill gas is being captured and converted to energy, thus reducing greenhouse gas emissions.

Co-Locating AD Plants at MRF/Transfer Stations

But another and even more effective way of capturing methane gas is to intercept waste that would otherwise go to a landfill and process it in an AD facility co-located at a MRF/Transfer Station.

An AD Case Study for California

CR&R, a recycling and waste services company serving about 2.5 million customers in Southern California has teamed up with ArrowBio, developers of an innovative wet MRF and AD process.

The Arrow system has been vetted by Los Angeles City and County, as part of a two-year assessment of alternative technologies.

AD Plant Case StudyCity of Los Angels RFP Process

The City of Los Angeles is in the final stages of selecting one or more alternative technologies to contract with over a twenty-year timeframe.

The ArrowBio AD technology has been highly rated.

The City of Los Angeles has long-range goal to reduce dependency on landfill, produce green energy and green jobs for the City.

AD Case StudyCounty of Los Angeles

CR&R and Arrow Ecology’s AD technology has also been selected by LA County after a two-year evaluation of technologies, both AD and thermal, from around the world.

The County is working with CR&R and Arrow to develop an AD project over the next two years.

AD Benefits

Major GHG reductionsRecovery of renewable energy, soil products and recyclables-bumping diversion rates approaching 90%.The technology integrates recycling with renewable energy and GHG reduction objectivesEconomic development through the design, construction and operation of AD plants in California

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System Benefits

Intercepts and converts biodegradable waste Intercepts and converts biodegradable waste to green energy before it is placed in landfillsto green energy before it is placed in landfills

Recovers more recyclablesRecovers more recyclables

Biogas is cleaner than landfill gas with a Biogas is cleaner than landfill gas with a methane content of 65-70%methane content of 65-70%

Modular and scalableModular and scalable

Reduced transportation impactsReduced transportation impacts

Dry sorting and plastic bag opening

Dry sorting and plastic bag opening

MAIN VAT

LIGHT FRACTION FLOW

HEAVY FRACTION FLOW

Ferrous metals

Second stageSecond stage

Non-Ferrous metals

Glass

Stones, Sand

First stage Hydro-Mechanical Separation

First stage Hydro-Mechanical Separation

Process FlowProcess Flow

PET HDPE

Textile, Leather

LDPE

SECONDARY VAT

Un-Sorted or Sorted MSW INPUT

Landfill

Second stage Biological anaerobic digestion

Second stage Biological anaerobic digestion

Bulky & negative items

First stageHydro-Mechanical Separation

First stageHydro-Mechanical Separation

Process Flow

Second stageBiological anaerobic digestion

Second stageBiological anaerobic digestion

Acitogenic Reactors

Methanogenic Reactor & Digesters

First Class Soil Amendment Biogas -> CNG

Biodegradable material from first

stage

Biodegradable material from first

stage

Energy Value of 50,000 tons of MSWEnergy Value of 50,000 tons of MSWUsing ArrowBio wet MRF and AD Using ArrowBio wet MRF and AD

ProcessProcessProduction of 100 % green energy -Production of 100 % green energy -biomethane. According to CARB this fuel has biomethane. According to CARB this fuel has an emissions impact that is about 6X lower an emissions impact that is about 6X lower than fossil-fuel derived natural gas.than fossil-fuel derived natural gas.

Produces an estimated equivalent of 760,000 Produces an estimated equivalent of 760,000 gallons/year – enough to power 80 heavy gallons/year – enough to power 80 heavy duty trucks (transportation option)duty trucks (transportation option)

Or about 1.3 megawatts of electricityOr about 1.3 megawatts of electricity

More than 99.5 % methane recoveryMore than 99.5 % methane recovery

– Global Warming Potential (GWP) of CHGlobal Warming Potential (GWP) of CH44 is is

21 times higher than CO21 times higher than CO22

Upgraded biogas exceeds Sempra and Upgraded biogas exceeds Sempra and

PG&E quality requirementsPG&E quality requirements

Pure and green COPure and green CO2 2 – a commercial value – – a commercial value –

can be capturedcan be captured

Biogas Upgrade Plant

Aerial View of Proposed 150 TPD Facility at the Project Site

100 Truck LNG Fleet Serving South Orange County

and Green Fuel Potential for California

The GHG emission reductions from converting 10,000,000 tons of biodegradable solid waste to biomethane derived fuel is 2,400,000 tons/year.

Converting 10,000,000 tons of biodegradable solid waste per year to biomethane could fuel approximately 16,000 heavy duty trucks per year.

Conclusions

Bridge funding through programs like AB 118 and the South Coast Air Quality Management District’s technology grant programs and/or early implementer contracts like the one under consideration by the City of Los Angeles are essential to building an AD infrastructure in California.

More public education and awareness of the benefits of AD is needed.

The path towards zero waste will require

advanced technology in addition to continued efforts to promote reycling, composting and waste prevention.