biogas workshop - may 4th v2

8/6/2019 Biogas Workshop - May 4th v2

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Rosalie Forest Eco Lodge

ECOFEST 2009

Introduction to Biogas, May 4th

, 2009

Presented by

Vincent Martineau

Jessica Worley


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Who We Are

Vincent Martineau, B.Eng Bioresource

Focused on sustainable technologies, water management and landdevelopment.

Jessica Worley, B.Eng Civil and Applied Mechanics

Specialty in geoenvironmental engineering and water resource

management.

Obtained biogas experience in Barbados during the Fall of 2007

Design and Construction of a BiOdigester

NativeSun NRG & Bellairs Research Institute


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Overview

Goals & Objectives

Anaerobic Digestion

Biodigesters

Biogas

Design Specifications

Recommendations

Source: www.knowledgepublications.com

Source: www.knowledgepublications.com


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Goal

Design and construction of a biodigester to producebiogas

Objectives

Create a source of fuel for cooking;

Provide a fertilizer from the digested waste;and

Improve health conditions by isolating wastesin a sealed container to reduce airbornepathogens from raw manure.


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What is a Biodigester?

A device that mimics the natural decay process of organic matter

Biogas is produced from anaerobic decay (decay that occurs withoutoxygen)


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Biogas: Green Energy

50-70% methane;

30-40% carbon dioxide;

Insignificant amounts of oxygen and hydrogensulfide (H2S).

Biogas burns without soot or ash being produced

Methane is a combustible gas

Biogas will be used to generate energy for thecooking needs here at Rosalie Forest Eco Lodge

(plascoenergygroup)


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History of Biogas

One of the oldest forms of renewable energy

Marco Polo mentioned the use of the technology.Probably goes back 2000-3000 years ago in ancientChinese literature

The earliest evidence of use in Assyria (10thcentury BC)


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History of Biogas

Jan Baptita Van Helmont determined in1630 that flammable gases could evolve

from decaying organic matter.

Anaerobic digestion first described byBenjamin Franklin 1764.

Count Alessandro Volta in 1776 found acorrelation between amount of decaying

organic matter and amount of flammablegas produced.

In 1808, Sir Humphrey Davy determinedthat methane was present in the decayprocess.


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History of Biogas Contd

First digestion plant was built in 1859 in Bombay, India for a lepercolony

Exeter, England, in 1895: biogas used to power street lamps

1920s and 30s interest in anaerobic digestion increased

Interest in Biogas has been cyclical


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Examples of Digesters Around the World

Costa Rica


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Digesters Around the World (contd)

India (ART

I)


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United States Princeton, MinnesotaPrinceton, Minnesota


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KVIC Digester(used in India and China)


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PrototypeWork log of what we did


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Design Advantages

Reduction in scum accumulationTemperature Control

Ease of operation

Durable

Small footprint

Low cost


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What Type of Waste Produces Biogas?

Any organic waste can produce biogas

Human, manure, fruit and vegetable waste

What Type ofWaste Does NOT Produces Biogas?

Fiber rich waste such as wood, leaves, etc. are difficult to digest

Heavy metals

Inorganic materials in high concentration (Nitrate, Sodium, Sulphate,Sodium, Potassium, Calcium, Magnesium, etc)


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How Much Biogas Can I Get From My Waste?

Amount of biogas depends on the waste itself and design of thedigester.

Some digesters can yield 20 liters of biogas per kilogram of waste up to

800 liters per kilogram.

Factors: waste quality, digester design, temperature, system operation,presence of oxygen.


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How Much Energy is in Biogas?

Average fuel value of methane = 1000 BTU/ft3

Average fuel value of propane = 2500 BTU/ft3

1 BTU/ft3 = 37.2589 KJ/m3


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How Much Energy is in Biogas?

Therefore, using the SI system, Fuel Value units:

FV methane = 1000 * 37.2589 KJ/m3 = 37258.9 KJ/m3

FV propane = 2500 * 37.2589 KJ/m3 = 93147.3 KJ/m3

FV propane / FV methane = 2.5

When both fuels are burned completely, propane produces 2.5 timesmore energy per unit of volume.


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How Much Biogas Do I Need?

For Example: We want 40 lbs of propane-equivalent per week.

Biogas is 50-70% methane, 30-50% CO2 and 5-15% N2, H2, etc.

40 lbs propane * 2.5 = 100 lbs of methane

100 lbs of methane / 60% = 166.67 lbs of biogas


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Specifications

Input: 1 kg of donkey manure, 1 kg of food waste and 15 liters of water

Volume of tank: 55 US gal (~208.2 litres, ~0.208 cubic meter)

Assuming:

Total Solids (TS) ~15%

Volatile Solids (VS) ~70%

Hydraulic Retention Time: 10 days


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How to calculate Organic Loading Rate (OLR)

OLR = kg VS added / day / m3 reactor

OLR = Manure * TS% * VS% / Volume

Organic Loading Rate: 2.02 kg VS added / day / m3 reactor


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How much money did we just save?

Methane production estimated at XXX m3/day (equivalent to XXX kg ofpropane/day)

Economic gain of about XXX $/year if fully used

Low Cost of construction: ~250 $EC


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Obstacles

Economic: Keeping itinexpensive

Time

Equipment: Limited

Weather: When it rains, itpours!

Problem Solving

Recycled materials

Have friends around

Borrow and buy

Work in-between theshowers!


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Implementation Plan

Research of existing technology and systems

Inventory of resources

Budget

Design

Construction

Testing

Cook!


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www.journeytoforever.org

www.anaerobic-digestion.com/index.php

www.biogas.psu.edu

www.arti-india.org/content/view/12/28

www.ruralcostarica.com/biogas.html

http://www.fao.org/docrep/t0541e/T0541E00.htm#Contents

Resources


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biogas workshop - may 4th v2

Documents