Small-Scale Solar-Biopower Generation For Rural Central America

Project support from:US Department of State, Western Hemisphere Affairs Energy & Climate Partnership of the Americas (ECPA)

Dana Kirk, Ph.D., P.E.Michigan State UniversityBiosystems and Agricultural Engineeringkirkdana@anr.msu.edu

Project Partners

PI – Ajit Srivastava, MSU BAECo PI – Wei Liao, MSU BAECo PI – Dawn Reinhold, MSU BAEEducational coordinator – Luke Reese, MSU BAE Project manager – Dana Kirk, MSU BAEFrancisco Aguilar – UCR AEDaniel Baudrit – UCR AEAlberto Miranda – UCR AELorena Lorio – UCR Micro Lidieth Uribe – UCR Micro

Core Project Team

1. Optimize local thermophilic anaerobic microbial consortia

2. Implement a solar-biopower generation system

3. Evaluate the technical and economic performance

4. Establish an outreach program in Central America

Project Objectives

Facts of solar energy

From: http://www.global-greenhouse-warming.com/solar.html

Advantages Theoretical: 1.76 x 105 TW

striking Earth, Practical: 600 TW

It is the cleanest energy source on the Earth.

Solar energy reaching the earth is abundant.

Disadvantages Sun does not shine

consistently. Solar energy is a diffuse

source. It is difficult to collect,

covert, and store solar energy.

Central America

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Facts of Biogas Energy from Wastes

Advantages A biological process Reducing greenhouse

gas emission Enhancing nutrient

management

Completely Stirred Tank Reactor (CSTR)

Anaerobic Sequence Batch Reactor (ASBR)

Plug-flow digester

Disadvantages Low efficiency of organic

matter degradation Difficulty of power

generation for small-medium operations

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Agricultural residues available in Costa Rica

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Residues Total amount (metric ton dry matter per year)

Current treatment practices

2006 Projection 2012 Cattle manure 1,530,000 1,679,900 Only 20% of producers treat wastes, dried

and compostedSwine manure 95,000 110,000 0.68% for production of energy and rest in

agriculture, fertilizer (45.5%) food animal (53.1%) or other uses (0.7%).

Banana residues 158,000 132,000 Not used as energy source,100% discarded or composted organic

Coffee residues (pulp) 251,000 (husk) 25,000

(pulp) 262,000(husk) 26,300

Pulp is used for composting, and husk is used for combustion

Sugarcane bagasse

1,290,000 1,518,200 95.3% dried and used as combustion, 4.7% non energetic

Pineapple residues

6,351,000 8,452,000 Combusted and soil improvement

More than 600 MW electricity per year could be potentially generated from this amount of waste streams through anaerobic digestion technology.

Integrating wastes utilization with solar and biological technologies will create a novel self-sustainable clean energy generations system for small-medium scale operations

Fertilizers

Reduced GHG

Animal Manure

Other Organic Wastes

BioenergySolar

Energy

AnaerobicDigestion

Post-treatment

Clean Water

Solar-biopower concept

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Benefits of system integrationOvercome the disadvantages of individual

technologies Unsteady energy flow for solar power generation Low efficiency of mesophilic anaerobic digestion on

degradation of organic matter Higher energy requirement of thermophilic aerobic

digestion

Provide sufficient and stable energy for small-medium sized rural community Solar energy utilization Improved efficiency of anaerobic digestion on

degradation of organic matter Biogas energy as chemical storage – steady energy flow

Solar-biopower concept

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Mass balance

Predicted mass balance for the integrated solar-bio system on 1,000 kg of mixed sludge and food wastes

Generating 66 kWh electricity per day Producing 5 gasoline gallon equivalent (GGE) renewable fuel

per day

Mixture of feedstocks:Total amount: 1,000 kg/dayTotal solid: 10% COD: 90 g/kg

Thermophilic CSTRReaction temp.: 50°CRetention time: 15 daysCOD reduction: 50%Total solid reduction:40%

Biogas production from anaerobic treatmentMethane: 18,000 L/day

Liquid effluentAmount: 595 kg/dayTotal solid: 10 g/kg effluentCOD: 45 g/kg effluent

Generator

Solid residue accumulated from the CSTRAmount: 360 kg/day wet solidDry matter: 15%

Boiler

To wetland

BioenergyAmount: 684 MJ/day

a. The calculation of mass balance was based on the expected results that will be achieved by this project. b. A kg COD destroyed produces 350 L methane gas.

Solar-biopower system

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Post-treatment

Solar unit

Power unit

Bioreactor

Construction site

Solar Bio-Reactor SiteFabio Baudrit Experiment

Station

16 – 2 m2 flat-plate solar collector with support22 m3 anaerobic digester 50 m3 gas bag 2 – 10 kW electric generators 4 – 144 m2 wetland/sand filter cells

Major system components

Solar Bio-Reactor Sand Filter / Wetland

Solar thermal system

Solar collectors, hot water tank (white),

& hot water storage (green)

Anaerobic digester

Official ribbon (digester in background clad in tin)

Poly tank anaerobic digester

Field engineering

Feedstock & digestate handling

Feedstock grinder, auger & mix tank (pump not shown)

Digestate solid-liquid separator

Biogas storage

Biogas sampling

Gas bag, foam interceptor, & scrubber

Full gas bag, May 2, 2013

Sand filter 1 Vertical wetland (sand filter 2)

Surface wetland 1

Surface wetland 2

Sand filter & wetlands

Feedstock: Beef manure (950+ kg/d) Food waste Chicken litter (20 kg/d)

Temperature: Currently 45oC±2oC Target 50oC±1oC

Biogas production: ≈20 m3/dBiogas quality: 60+% CH4Volatile solids destruction: 39% to 44%

Solar-biopower system performance

Original waste stream

The effluent from solar-bioreactor

The water from the 1st cell of post-treatment

The water from the 2nd cell of post-treatment

Organic waste

Reclaimed water

Anaerobic digester

Sand filter No. 1

Sand filter No.

2

May 2013

Water reclamation

Pilot system Biogas production at 70% of goal Biogas quality and solids destruction have achieved

goals Install biogas flow meter Connect electrical generators to the experiment

station power Begin sand filter/wetland research

Bioenergy support lab at UCR – capable of carrying out BMP’s and other analysis

Utilization of local manufacturing – coffee equipment & solar panels

Study abroad “Ecological Engineering in the Tropics” completed in December of 2012

Outcomes to date

Finalize microbial consortia papersContinue to operate pilot system until Sept.

2014Operate portable unit at second location –

wastewater or food processorComplete economic and policy evaluation2013 study abroad planned for DecemberExpand bioenergy capabilities to address

commercial needs

Next steps

August 13, 2013 – MSU Waste to Resource Field Day Highlights:

South Campus Anaerobic Digester (500 kW from 130 cows)

Research digester, compost facility, student organic farm, recycling center, power plant, ADREC

For more information go to :http://events.anr.msu.edu/adrec/

October 15 to 17 – Anaerobic Digester Operator Training (East Lansing, MI) Highlights

System commissioning Maintaining biological health Safety Operational troubleshooting

For information contact kirkdana@anr.msu.edu

Other announcements

Questions?

Dana M Kirk, Ph.D., P.E.Biosystems and Agricultural Engineering

Anaerobic Digestion Research and Education CenterE: kirkdana@anr.msu.edu

P: 517.432.6530