甘比亞生質燃料棒生產潛力之研究

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國立臺灣大學生物資源暨農學院農業經濟學系

碩士論文

Graduate Institute of Agricultural Economics College of Bio-Resources and Agriculture

National Taiwan University Master Thesis

甘比亞生質燃料棒生產潛力之研究

A study of biomass briquettes potential in the Gambia.

Ibrahim Colley 柯里指導教授 : 徐世勳

指導教授:蘇忠楨

Advisor: Dr. Shih-Hsun Hsu, National Taiwan University Co Advisor: Dr. Jung-Jeng Su , National Taiwan University

中華民國 103 年 6 月

June 2014

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ACKNOWLEDGEMENTS

I am grateful to ALLAH THE ALMIGHT, for given me the strength and courage to complete my program.

I specially wish to express my sincere and warmest gratitude to Taiwan International Cooperation Development Fund (ICDF) for providing me the scholarship to pursue MSc degree in Agricultural Economics.

I wish to express my profound gratitude and appreciation to my untiring and open hearted supervisor, Dr. Shih-Hsun Hsu, Dr. Jung-Jeng Su and Dr. Pio-Po Lee for the successful completion of this thesis.

I also wish to express my heartfelt thanks to staff of the Department of Agricultural Economics of the National Taiwan University for the support during the program.

Final thanks to my dad and late mother for having the foresight of taken me to school, and I will always remember you people. More so my late mum may the blessing of Allah Almighty continues to shower on you, Amen.

Ibrahim Colley Department of Agricultural Economics, National Taiwan University, June 2014

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DEDICATION

This piece of work is dedicated to my beloved wife Mariama Makalo and kids Muhammad Sheriff Colley, Amatul Malik Teeda Colley, Umar Ahmad Colley and Abubakr-As-Siddiq Colley who was born while I was away, I cherish their patient and understand during my absent

from them.

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A Study of Biomass Briquette Production potential in The Gambia, Taiwan New Bonafide Company as the best practice model for the Gambia to follow using SWOT analysis.

The need for alternative sources of energy becomes a fast necessity against the backdrop of decreasing trends of availability of fuel wood and charcoal for cooking in the country and also high price of petroleum products. The world economy is dominated by technologies that rely on fossil fuel energy (petroleum, coal, and natural gas) to produce fuels, power, chemical and materials. While the use of conventional energy like oil, coal and electricity has grown enormously in the last half century. This heavy dependence on imported oil leads to economic and social uncertainties.

Biomass have the ability to substituted for fuel and the conversion technologies are well developed which can transformed biomass to solid and liquid for heating, cooking and electricity generation.

In the Gambia there is ample availability of biomass for efficient energy conversion and production of briquettes is both economic and financial viable and there’s no legislative barriers for the conversion biomass into briquette, currently the non participation of private individual or companies in the sector prevent it from reaching its full potential.

Keywords: Biomass; Briquettes; Bio-energy; Densification; pellets.

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CHAPTER 1: INTRODUCTION

1.1: Motivation of the Study

Currently there is huge and growing demand to find alternative cleaner energy sources that meet new legislation requirements to reduce emission from fossil fuels in the Gambia. Agro- waste and timber milling waste as sources of energy in The Gambia shows great potential. The process of briquetting is the physical transformation of loose raw material mostly made of agro waste like peanut shells, rice husk and straw, maize stalks /cobs, cotton stalks, saw dust to name but not a complete list, into high density fuel briquettes through a compacting process. The resultant form change increases the calorific value (combustion efficiency) of the product as compared to loose material.

Biomass briquettes have the potential as a household domestic energy and a substitute for fossil fuel consumption due to the facts that it could also be used in thermal electricity generation as it is happening in developed nations. The utilization of briquettes for in the boiler for co-firing will reduce our dependence on imported fossil fuel and also created domestic energy source for the power generation.

Biomass briquette production and trade will contribute to the national economy by providing incomes, tax revenue and employment whereby a large number of people can be employed in the various phases of the biomass briquette value chain, including: collection of agro-waste and wood saw dust for preparation of briquettes, packaging and transportation.

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In additions a huge quantity of agro-waste residues which goes either rotten or mostly set on fire, because they are considered to be useless, or worthless item and or as a nuisance, can be transformed into a very useful form of cleaner sources of energy.

Briquette production can also significantly reduce pressure on the already fragile Gambian forest, as evident shows that ample agro- residues and timber milling product are available in the country which can be transformed into briquettes.

Furthermore, the heating and boiling capability of biomass briquettes are more efficiency than fuel wood and charcoal. Briquettes are considered to produce less ash and are smoked free during burning. Therefore it is imperative to say, the development and marketing of an efficient cooking stove for utilization of briquettes is deem a necessity.

The use of fuel wood as an energy source can also contribute to the accumulation of Co2, the main greenhouse gas, both because burning fuel wood produces Co₂, and because deforestation destroys an important Co2 sink. The use of such unprocessed bio-fuels results in several hard ships and injury’s especially for women and children, time spent on fuel collection, health impact suffered from air pollution, with an increased in burden of cleaning utensils, walls, floors and clothes, and ecological changes are severe negative consequences.

It is important to note that, lucrative investment in briquette productions will also chart ways for us not to depend on one sources of energy or foreign supply of fuel wood and charcoal into the country, as it could have a serious implication during trade stand-off from a foreign supplier.

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Marketing of briquettes to the international market will earn foreign currency for the investors or government which will also stabilize the rate of inflation in the country.

Biomass briquettes can offer a Sustainable supply of fuel for the energy demand.

And above all it is clear that it can save money, even make money, if people switch to sustainable alternative fuels.

1.2: Energy Sub-Sector

One of the determinants of social-economic development is the availability of reliable and affordable sources of energy since these have direct positive impacts on quality of life and poverty. A review of The Gambia energy sector reveals that the country’s energy resource base is limited and the supply system is unreliable. The main source of energy used in the country is fuel wood, followed by petroleum products, electricity and renewable energy. In the energy sector, fuel wood obtained from biomass represents over 80% of the total primary need of the country (GOTG, 2007)

The Government of the Gambia envisions a diversified energy system that is reliable, efficient, affordable and environmentally-friendly and pursed improvement in electricity, renewable energy and petroleum supplies.

Renewable energy sources consist of solar energy, wind energy and biomass. These energy forms, in particular solar and wind belong to the modern sector. Currently the solar energy is in the market and a number of companies are operating in the solar energy sub-sector.

They include Gam Solar, VM The Gambia Limited, Gambia Electrical Company, SWEGAM and Dabakh Malick Energy Centre. On biomass briquette energy sources only one company is

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operating in the briquettes energy sector, which cannot even supply of the population in the urban area and are only manufacturing groundnut shells as briquettes.

1.3: Importance of the Different Energy Sub-Sectors in the Gambia

Table 1.1, shows the percentage shares of each type of energy in the household energy basket. The importance of the different energy types, in a descending order, based on their shares of the household energy balance are fuel wood (firewood & charcoal), petroleum (kerosene &

LPG), electricity (thermal) and renewable energy. Fuel wood tops the list in terms of both quantity and value. The rural households consume more fuel wood than the urban household.

However, whereas the rural households consume more firewood than the urban households, the latter consume more charcoal.

Both households consume more fuel wood than electricity. The urban households spend more on electricity whereas the reverse is true for the rural households. Electricity attracts the highest value. Report of the charcoal sector review, (2005) about 60 percent of total fuel wood consumption comes as import from Senegal.

Table 1.1: Percentage Contribution of the Different Energy Sub-sector to the National Household Energy Balance in 2004.

Source Percentage (%) Contribution mix

Fuel Wood 96.96

Petroleum 1.60

Electricity 0.88

Renewable 0.56

Source: Household Energy Consumption Survey 2004

1.4: Energy and Biomass from Agriculture: an important Policy issue for the Gambia

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The Gambia should now establish policy goals and targets to develop bio-energy production from agriculture. The following six points are the foundation why the Gambia should enter into biomass briquette production.

Energy Security: with recent concerns rose over the reliability of fuel supplies and the raising price, the country need to seek for an alternative energy security for domestic energy supplies by expanding biomass briquettes production.

Environmental Effectiveness: the expansion of bio-energy and biomaterial production are seen to help toward achieving other government environment objectives, such as improving air quality e.g. to reducing smoke particulates and also inhalation of hazardous smoke emanating for burning of waste.

Rural Development: the increase in biomass briquettes production will offers the potential to expand market opportunities for agriculture, while providing a raw material to stimulate rural and regional industrial development and employment.

Economic Efficiency: bio-energy production offers the opportunities to use agricultural wastes and reduce costs of their disposal, but also, through using less non-renewable products, lowering costs of non-recyclable and hazardous wastes. With the creation of a recycling society, there is a determination by many governments to improve economic efficiency of energy and raw material use in household and industry.

Market Innovation: agricultural biomass is also associated with the development of a bio-economy as an engine of growth and market innovation. This can offer possibilities in developing local solutions to energy needs and industrial development, but also the opportunity for export potential based on new and emerging bio-based technologies

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Climate Change: with many countries committed to reduce greenhouse gas (GHG) emissions under the Kyoto Protocol of the UN Framework Convention on Climate Change, bio- energy provides a source of renewable energy associated with low carbon dioxide emission levels compared to the use of fossil fuels. In addition, there are possible future business opportunities from carbon credits (such as bio-energy) and carbon sinks through international carbon markets.

1.5: Objective of the Study

To estimate the sustainable supply of agricultural residues for biomass briquetting production in the Gambia.

To identify the potentials of producing briquettes from agro-residues that are grown in the country and in addition to the ample availability of forest wood residues such as saw dust.

To examine the financial and economic viability of producing biomass briquettes at a lower cost, compared to fuel wood and charcoal

To determine the efficiency of biomass briquettes as a good sources of heating and boiling

1.6: Organization of the Thesis

The thesis is organized into six chapters. Chapter I presents introduction which covers country profile, brief discussion on country’s energy sector and biomass, motivation, aim and objectives of the research and the methodology, Chapter II provides a General overview of Economic and Business of biomass briquette production and consumption industry globally.

Chapter III reviews Biomass Briquette Technology and uses in different countries. Chapter IV

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Methodology and a case study on briquette production in Taiwan with Reference to the New Bonafide Machinery Company (NBM). Chapter V provides an Analysis of Feasibility study on biomass briquette production in the Gambia and Chapter VI summarize our Conclusions and Recommendations.

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CHAPTER 2: BACKGROUND OVERVIEW OF THE ECONOMICS AND BUSINESS OF BIOMASS BRIQUETTE PRODUCTION AND

CONSUMPTION

2.1: General Overview of Economics and Business of Biomass Briquette Production and Consumption

Energy is key in economic growth of a country. The global energy use is rising very rapidly, and the world will continue to see energy demand skyrocket. The creation of biomass energy dates back to first time fire was lit. Modern energy projects go far beyond the primitive resources of simply lighting and sustaining a fire. Benefiting from computer aided design and latest incineration technologies, this system are used to heat whole communities, and meet utility-scale electrical demand. To that end, both investors and governments have been exploring solutions, such as efficiency measures and renewable energy generation as a way to satiate that exploding demand. The use of biomass residues and wastes for chemical and energy production was first seriously investigated during the oil embargo of the 1970s, Nandini Shekhar,(2010).

Many of the developing countries produce huge quantities of agro residues but they are used inefficiently causing extensive pollution to the environment which is truly visible in the third world counties. The major residues are rice husk, coffee husk, jute sticks, bagasse, groundnut shells, oil palm, maize stalk, cotton stalks and even saw dust.

Traditional biomass fired cooking stoves have two major draw problems, ie., low efficiency and indoor air pollution created by pollutants (which have been linked to different health problems) released inside the kitchen. The biggest improved cook stove (ICS) programs of the world are being undertaken in China where 177 million stoves have been installed so far covering 76 percent of the rural households (Junfeng et al. 2000) and in India where about where about 333.8 million improved cook stoves were installed by 2001(MNES, 2002).

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Biomass energy currently plays a major role in meeting the present energy needs of developing countries. A number of authors (Beyea et al., 1991), have also expressed the view that biomass has the potential to meet the additional modern energy demands of urban and industrial sectors, thereby making a significant contribution to the economic advancement of developing countries. Biomass can also offer an immediate solution for the reduction of the Co2 content in the atmosphere. In addition to its positive global effect by comparison with other sources of energy, it presents no risk of major accidents, as nuclear and oil energy do.

Figure 2.1: 2011 fuel shares of world total primary energy supply Source: IEA, key world energy statistics, 2011

The dynamic of price rise in commercial fuels (oil, kerosene, coal), has forced even the urban poor to use fuel wood for cooking in developing countries. (IEA, 2006).

Fuel wood still serves as the major sources of energy in the rural areas and business of fuel wood collection is the livelihood most resorted to for millions of people, fuel wood collection is an indicator of severe rural distress, ecological degradation and failure of agriculture to sustain the rural economy.

Hydro Coal/Peat Oil

Natural gas Nuclear Biofuel/waste Others 5.80

%

20.90%

10.20 % 2.30 %

27.20 %

32.80 %

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Biomass briquettes may hold the answer for emerging and developing countries, as well as countries which are more established.

Table 2.1: People (in millions) relying on traditional biomass

Countries 2004 2015 2030

Sub Saharan Africa 575 627 720

North Africa 4 5 5

India 740 777 782

China 480 453 394

Indonesia 156 171 180

Rest of Africa 489 521 561

Brazil 23 26 27

Rest of Latin America 60 60 58

TOTAL 2528 2640 2727

Source: International Energy Agency, 2006

For example in Asia nations, India, Malaysia and Vietnam, Nepal, Thailand and Philippines are doing very well in biomass briquettes production, in India (Maninder et al., 2012), the potential of biomass briquetting in India was estimated at 61,000 MW, while the estimated employment generation by the industry is about 15.52 million and the farmers earn about $ 6 per ton of the farm residues. A comparison of coal and briquettes reveals that, briquette has superior qualities as well as environmental benefits in comparison with coal. As shown in Table 2.2.

Table 2.2: Comparison of coal and biomass characteristics Fuel Density g/cm3 Calorific value

Kcal/Kg

Ash content %

Coal 1.3 3,800-5,300 20-40

Biomass briquettes from

Saw dust 1.1 4,600 0.7

Groundnut shell 1.05 4,750 2.0

Rice husk 1.3 3,700 18.0

Saw dust cotton 1.12 4,300 8.0

Source: Maninder et al., 2012

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In Malaysia, the briquette industry was started with wood wastes, mainly in the form of saw dust. Most of the local saw dust briquettes or charcoal briquettes are exported for oversea markets. The products are rarely used in the local markets as it could not compete with availability of cheap fuels such as wood, charcoal and kerosene.

2.2: Global market for biomass production and consumption

In 2012, global production and transport (by road, rail, and ship) of pellets exceeded 22 million tones. (See Figure 2.2). It suitable for co-firing in coal-fired power plants and the option of automatic control options in small heat plants. About two-third of pellets production is used in small heat plants and one-third in large power plants. (Ren 21, 2013).

Figure 2.2: Wood pellet global production, by country or region, 2000-2012 Sources: REN 21, 2013

Germany is currently the EU’s largest pellet producer, with more than 2 million metric tons of production in the 2013. Sweden and Austria are each expected to produce a relative 1.25 million metric tons and 950,000 metric tons of wood pellets in 2013. Portugal, France, Italy and Poland are also ranked among Europe’s top wood pellet producing nations. Overall production

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capacity use in Europe has held steady at near 62 percent since 2010. That trend is expected to continue into 2014. (Erin Voegele, 2013).

The U.S. was the main supplier of wood pellets in the 2012, with 1.764 million metric tons delivered. Canada supplied 1.346 million metric tons of pellets to Europe. Russia, Ukraine, Croatia and Belarus supplied a relative 637,000 metric tons, 217,000 metric tons, 136,000 metric tons and 112,000 metric tons of wood pellets to Europe. Martin Junginger et al (2014)

The EU is by far the biggest pellet consumer worldwide, burning some 15 million tons in 2012. According to the latest available figures from Aebiom, the European biomass energy association, biomass accounted for 8.4 percent of the total final energy consumption in Europe in 2011, while in some Baltic countries, such as Estonia, Latvia, Finland and Sweden, the figure is above 25 percent. The trade group adds that EU pellet consumption for heating has grown by more than one million tons per year since 2010. (David appleyard, 2014).

Around 8.2 million tons of pellets were traded internationally in 2012. More than 3.2 million tones (40%) of pellets were shipped from North America to Europe, an increase of nearly 50% over 2011. This increase in demand was due to rising consumption in UK, where large volumes are required to supply the 750 MW Tilbury bio-power station and a 4 GW coal-fired power plant ( half of which is being converted to combust 7.5 million tons of pellets annually).

Denmark and the Netherlands round out the top three consumers, with 2.5 million metric tons and 2 million metric tons of consumption expected this year. Sweden, Germany and Belgium also consume large volumes of pellets (Ren21, 2013).

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While pellet consumption in the U.K., the Netherlands and Belgium is dominated by large-scale power plants, demand in Denmark and Sweden also results from household and medium-scale district heating consumption. Pellets consumed in Germany, Austria, Italy and France are mainly used in small-scale residential and industrial boilers for heating purposes.

( Sikkema et al. 2011; E. Voegele, 2013).

Pellets consumption is growing in other region as well. in South Korea, eight new pellets plant were under construction as of early 2013. There are also plans to import an additional 2 million tones. The demand for fuel briquettes is huge and increasing every year. The annual demand is increasing by more than 11% each year. If such a small country has such a steadily increasing demand, the global scenario needs no explanation. (Altprofit., 2013). Production in Asia largest consuming nations is low which is South Korea and Japan, Countries likes Chain, Thailand, Indonesia, Vietnam and Malaysia are also using plenty of biomass (piers even, 2013)

In underdeveloped African countries, the demand for briquette is even higher than the global scenario. For example, in Uganda, over 93% of domestic fuel is in the form of briquettes and wood charcoal. And some east African nations like Tanzania, Kenya, and also in west African nations like Ghana, Sierra Leone, Mali, Niger, Nigeria and Liberia which have an agreement with the Swedish utility company vottenfall AB to supply them one million tons of wood chips sourced from Liberia rubber plantation annually, (Task 40., 2011), nevertheless, there is no statistical data to support the consumption in tons are not available.

In considering a global forecast for bio-energy in the coming years, a recent study from the International Renewable Energy Agency (IRENA) and the German Biomass Research Centre (DBFZ) “Biomass Potential in Africa,” is perhaps instructive.

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The analysis drily observes: “Due to the large range in results presented by the reviewed studies, no definite figures regarding the availability of biomass in Africa can be provided.”

As much in Africa as anywhere else, with resources, demand, markets and technology, like nature itself, bio-energy really is world of possibilities. (David Appleyard, 2014)

NB: Modern renewable energy can substitute for fossil and nuclear fuels in four distinct markets: power generation, heating and cooling, transport fuels, and rural/off-grid energy services.

2.3: Uses of Biomass Briquettes

Until in the middle 19^th century, biomass dominated the global energy supply with a seventy percent shared (Grubler and Nakicenovic, 1988) and fuel wood are the most prominent.

When it come to the rapid increase in fossil fuel use, the share decline steadily through substitution by coal in 19^th century and later by refinery oil and gas, during 20^th century.

During 1974 to date global biomass consumption of energy grew annually by over 2 percent. Biomass resources contribute about 12 percent of global energy, and about 38 percent energy in developing countries. The biomass briquettes are mostly used for cooking, heating, barbequing and camping in the countries such as U.S.A, EU, Australia, Japan, Korea and Taiwan.

But of recent they are now use for thermal power electricity generation in the developed nations.

In the developing countries, biomass briquettes are mainly for household usage only for cooking and heating. Considering the facts that, biomass is the fourth largest source of energy worldwide and provide basic energy requirement for cooking and heating of rural households in developing

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countries. For large commercial scale it can be used as fuel in producing steam, district heating and electricity generation (A.B. Nasrin et al. 2008). Figure 2.3 below shows the usage.

Figure: 2.3: Biomass to energy pathways Sources: REN 21(2013)

2.4: Biomass Power Generation in developed nations.

Biomass is now used for power generation in developed nation exclusively or through co- firing with coal in coal plant. New wood fired plant in UK and France will see biomass capacity in these countries grow 50% by 2013; new biomass power plants have also been built currently in Scandinavia, Germany, Austria, Japan, South Korea and China. Scandinavia countries will continue to have the biggest use of biomass, due to their relatively large quantity of timber resources. A further 130 new plant are being built all over Europe and UK, which take the total plant in Europe to 1050 biomass plants and biomass generating capacity to 10,000 MW by 2013.

In USA 222 Biomass plants already established and the total capacity 7,475.20 in million and additional 660 coal power plant which can co-fire with biomass. (Treena Hein 2014).

In Asia, the demand for biomass for power generation is on the increase, in South Korea the short term development of biomass demand growth from 200,000 tones pellets equivalent to 1.8-2.0 million tons by 2015, and 5 million tons by 2020 which will account for 10% of energy

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power supply. In Japan an expect increase from 1,5 million tons in 2012 to 3.0-3.5 million tons in 2015 because of the Fukushima Nuclear disaster Japan is eyeing all renewable energy to dilute it heavy reliance on nuclear power. Countries like China, Thailand, Indonesia, Vietnam and Malaysia uses plenty of biomass, but Japan and South Korea look set to dominate the sector in Asia, while in Taiwan the market is showing movement. (Piers even, 2013).

In Africa it development have not yet reached the stage of power generation, it’s mostly in the form of cooking and heating.

2.5: Biomass Advantages Compared to Renewable Energy

A comparative analysis was done to know the difference on the economic advantages of different renewable for power generation, it proved that biomass have advantages over the solar and wind energy sources. The cost of biomass power is already been decreasing. According to (US DOE, 2007), it is expected that biomass power facilities will show a decrease trend during the next years. But considering evidence, we see that most costs of installed facilities are already decreasing. On a global scale, the wind, solar and hydro industries are worth more than $1 billion annually, and developing countries continue to embrace the waste-based technologies of biogas and biomass power. While cost has typically been the biggest development hindrance, that is slowly starting to change. The International Renewable Energy Agency points out those recent years have seen dramatic cost reductions as a result of research and development and accelerated deployment. Table 2.3, below illustrates the advantageous of biomass over the other renewable energy sources, looking at the different categories of comparison.

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Table: 2.3: Biomass of advantages compared to renewable energy

Power General Solar Cell Wind Biomass

Total Investment (million US$)

1,830 12,700 6,300

Facility Scale (KW/year) 1,000,000 10,000,000 10,000,000

Yearly Operation Rate (%) 12 20 70

Yearly Electricity Generation (million KWH)

1,100 17,500 61,300

Unit Investment (US$) 1.66 0.72 0.10

Source: “21 century by biomass energy”, Sakai Masayasu, 2012.

2.6: Cost Comparison of Energy Sources.

The cost comparison of energy source reveals that in their raw form they are both free and practically infinite, the equipment needed to collect, process, and transport the energy to the users are neither one. Currently, the RE costs are generally higher than that of fossil-based and nuclear energy. In addition to this, unlike well-established conventional designs, the advancement in different RE technologies still requires substantial investments. The economists often use so-called levelized energy costs (LEC) when comparing different technologies.

The LEC represents the total cost to build and operate a new power plant over its life divided to equal annual payments and amortized over expected annual electricity generation. It reflects all the costs including initial capital, return on investment, continuous operation, fuel, and maintenance, as well as the time required to build a plant and its expected lifetime. Table 2.4 compares the US average levelized electricity cost in dollars per kilowatt-hour for both non- renewable and alternative fuels in new power plants, based on US EIA statistics and analysis from Annual Energy Outlook, 2013.

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Power Plant Type Cost $/kW-hr

Coal $0.10-0.14

Natural Gas $0.07-0.13

Nuclear $0.11

Wind $0.09-0.22

Solar PV $0.14

Solar Thermal $0.26

Geothermal $0.09

Biomass $0.11

Hydro $0.09

Source: US DOE (2013)

Note that the numbers for each source are given for a different capacity factor, which complicates direct comparison. Notwithstanding, I believe these figures are useful in comparing different power generation methods. Also note that the values shown in the table do not include any government or state incentives. In other words, they represent the actual cost to the society.

We can see that so far coal and natural gas are the most economic fuels. However, in future the price of coal-based electricity can nearly double due to government imposed cost on CO2

emissions. Photovoltaic systems can be three times more expensive than fossil-based ones.

2.7: PRICE OF BRIQUETTE.

Table 2.5, below shows the price of biomass briquettes at the global level in different countries: the difference in price is not only the country specific but the products; the price of wood briquettes is high on the market than rice straw, husk, and bagasse etc, because wood product produce little ash compared to other straw, husk, and bagasse. Countries in the Scandinavian region are trying to have a common purchasing price for briquettes at a range of

£125 per tones and some other EU countries. The briquette price in Canadian market is too high.

Table: 2.5: price of briquettes

COUNTRY PRICE PER TONNE

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Malaysia, kuala lumpur, sabah, and perak $75-$140

Nepal Chitwan $160

Serbia $89

Nigeria Lagos $70-$90

USA, Wisconsin, Washington, Colorado $64-$160

Ghana Accra $75

Vietnam Ho Chi Minh $75-$145

Tanzania $250

China Hunan $170

Canada $250-$350

Scandinavia €125

India Rupee 5000-8000

Taiwan, Taichung, Keelong $120-145

Japan $150-160

Sources: Biomass Briquette system LLC (2010)

NB: It’s important to note that prices in Europe, America, Canada and Africa and Asia differ considerable, it appears that no single price prevail in all the nations.

2.8: Biomass Densification in Africa.

According to Karekezi (2002), recent years have seen an upsurge of interest in biomass briquetting. There are large-scale functioning briquetting plants in Ethiopia, Kenya, Malawi, Uganda, Sudan, Zambia, Zimbabwe, and Tanzania (OSCAL, 2002). Biomass briquettes have found limited application in certain other countries as well, e.g. Cameroon, Eritrea, Ghana, Rwanda, Senegal, etc. however, briquetting experience in Africa appears to be limited to certain pockets in most countries.

The main raw material commonly used for briquetted in Africa include coffee husk, groundnut shell, saw dust, bagasse and cotton stalks etc.

Practically all types of densification machines have been tried in Africa; these include imported screw presses for briquetting saw dust in Eritrea, Malawi, Tanzania, and Ghana, piston presses used for briquetting coffee husk in Kenya and groundnut shell in Sudan, and pellet

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presses for densification of groundnut shells in Zimbabwe and Senegal and sunflower husk in Zambia. ABC Hansen A/S, a group of companies headquartered in Denmark, appears to have established nineteen briquetting plants in several African countries, e.g. Burkina Faso (1), Ethiopia (7), Eritrea (1), Gambia (1), Kenya (2), Nigeria (1), Rwanda (1), Sudan (4), Zambia, Zimbabwe; it appears that more than half of these are still in operation.

Besides, conventional binder less briquetting, low-pressure cold briquetting using binder has also been tried in some places. The carbonization-briquetting process has been tried for cotton stalk in Sudan and coffee husks in Kenya. Briquetting of bagasse using molasses as binder has been reported to have had limited success in Sudan. Low-pressure binder less briquetting process of Legacy Foundation has been attempted in some African countries, notably Kenya and Malawi and most East and Southern African countries (Stanley, 2002).

In the African Great Lakes region, work on biomass briquettes production has been spearheaded by a number of NGOs with GVEP (Global Village Energy Partnership) taking a lead in promoting briquette products and briquette entrepreneurs in the three great lakes countries; namely Kenya, Uganda, Tanzania. This has been achieved by a five year EU and Dutch government sponsored project called DEEP EA (Developing Energy Enterprises Project East Africa). The main feed stock for the briquettes in east Africa has mainly been charcoal dust although alternatives like saw dust, bagasse, coffee husk and rice husks have also been used.

2.9: Raw materials for biomass Densification in different regions.

The most common raw material for heated-die screw-press briquetting machines are saw dust and rice husk. Some other raw materials, e.g., coffee husk, tamarind seeds, tobacco stems,

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coir pith and spice waste have also been used in India (vempaty, 2002). Saw dust is practically the only raw material used for producing briquettes, which are subsequently carbonized; it is the dominant raw material in Malaysia, Philippines, Thailand, and Korea. On the other hand, rice husk is the only raw material used in Bangladesh, Vietnam etc.

Piston press briquetting machines use a wide range of pulverized raw materials; in India, these include saw dust, ground nut shell, coffee husk, sugar cane bagasse, cotton stalks, sun flower stalks, spent coffee waste etc. peanut shell and cotton stalks appear be to the most important raw material in Africa.

The raw material mostly used in developed countries is saw dust and wood wastes.

2.10: Benefits from biomass briquettes production

Below are some points of indication in regards to benefits from biomass briquettes production.

Health

Thousands of people are exposed to indoor air pollution from toxic fumes of cooking fuels and kerosene lanterns, resulting in chronic eye disease, respiratory disease and lung conditions. Biomass briquettes have the capability to supply high quality, more efficient and cleaner forms of energy for cooking so as to reduce the incidence of associated deaths and diseases.

Pollution

Briquettes are immeasurably cleaner than the other sources alternatives fuel. Eg coal, because it does not contain any sulphur. Dust pollution associated with direct combustion of

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loose biomass can be avoided by switching over to Briquettes. Moreover the chance of fly ash is minimized when Bio Coal Briquettes are burnt.

Efficiency

Uniform physical dimensions & combustion characteristics, results in more efficient energy conversion. Briquettes burn in a controlled manner, slow and efficiently because of lower moisture content, higher bulk density, and lower ash content. More and more, utility Industries are using biomass briquettes to supplement or replace coal as a solid fuel source.

Reducing pressure on the forestry cover

A large area of the forest is been cut for fuel wood for cooking, which have lead to drastically deterioration of the environment of it natural vegetation and also endanger the survival of animals in the forest land, biomass briquettes productions from the agricultural residues can significantly address the pressure on the forest wood fuel or charcoal for cooking.

Cost

The purchase price of biomass briquettes is less than, petrol, diesel, and Coal , and fire wood.

Quality & Clean Fuel

Biomass Briquettes has consistent quality & it is very clean to handle.

Economic benefits

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Economic activity associated with biomass briquettes production can supports deals in the business and create employment opportunities, which could significantly benefit rural economies.

Biomass energy crops can be a profitable alternative for farmers, which will complement, not compete with, existing crops and provide an additional source of income for the agricultural industry. Biomass energy crops may be grown on currently underutilized agricultural land. In addition to rural jobs, expanded biomass power deployment can create high skill, high value job opportunities for utility, power equipment, and agricultural equipment industries.

Environmental benefit

Biomass fuels produce virtually no sulfur emissions, and help mitigate acid rain, Biomass fuels "recycle" atmospheric carbon, minimizing global warming impacts since zero "net" carbon dioxide is emitted during biomass combustion, i.e. the amount of carbon dioxide emitted is equal to the amount absorbed from the atmosphere during the biomass growth phase. biomass wastes mitigates the need to create new landfills and extends the life of existing landfills, produces less ash than coal, and The biomass ash can also be used as a soil amendment in farm land.

Reduction in Injury and bruises

Biomass briquettes will considerably reduce the injuries and bruises occur during collecting of fuel wood in the forest.

Reduction on child labor

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Briquettes production will may it possible to reduce the number children, who go to forest for collecting fire wood for family use, and it will help the children to spend more time studying them these hazardous work.

Serve as pesticides

The remaining products after burning can serve as pesticides against insects attached to field crops.

It can motivate high production

Briquettes production can motivate farmers to produce and even diversify their agricultural production. The residues that were considered as waste can also provide some additional income for the farmers.

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CHAPTER 3: Biomass Briquette Technology and Uses in Different Countries.

3.1: biomass and bio-energy

Biomass: is any organic materials, i.e. decomposing, matter derived from plants or animals available on a renewable basis. Biomass includes all kinds of vegetative and organic waste. Good examples of biomass are (i) Agricultural waste left behind in the fields after harvesting (ii) plant material left in the forest after collection of timber (iii) bagasse in the sugar industry (iv) rice husk in rice mills (v) saw dust from timber milling machine wood (vi) groundnut shell (vii) municipal solid waste (MSW) (viii) energy crop that are separately cultivated for their fuel content Ghosh, K.P., 2002.

Bio-energy: is energy derived from the conversion of biomass where biomass may be used directly as solid fuel, or processed into liquids OECD, 2004.

(International Energy Association, IEA, 2009, biomass-based energy accounted for roughly 10%

of world total primary energy supply in 2009. Most of this is consumed in developing countries for cooking and heating using very inefficient open fires or simple cook stoves with considerable impact on health (smoke pollution) and environment (deforestation). Modern bio-energy supply on the other hand is comparably small, but has been growing steadily in the last decade. A total of 280 TWh of bio-energy electricity, i.e. 1.5% of world electricity generation, was generated globally in 2010, and 8 EJ of bio-energy for heat were used in the industry sector.

Analysis in the IEA Technology Roadmap: Bio-energy for heat and power suggests, that in order to achieve significant emission reductions in the energy sector, sustainably produced bio-energy will play an increasing role in the future with demand increasing three-fold to 2050.

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While several technologies for generating bio-energy heat and power already exist, there is a need to extend the use of the most efficient technologies available today, and to complete the development and deployment of a number of new technology options. Co-firing biomass with coal will be an important option to achieve short-term emission reductions, and make use of standing assets. In addition, new dedicated bio-energy plants will become increasingly important to meet growing demand for bio-energy electricity and heat.

While in favorable circumstances producing energy from biomass can be cost competitive today. In many cases, economic incentives are currently needed to off-set cost differences between bio-energy and fossil fuel-generated electricity and heat. Such support is justified by the environmental, energy security and socio-economic advantages associated with sustainable bio-energy, but should be introduced as transitional measure leading to cost competitiveness in the medium term. Support measures should be backed by a strong policy frame work which balances the need for energy with other important objectives such greenhouse-gas (GHG) reduction, food security and biodiversity, and socio-economic development.

3.2: Biomass Power Generation Technologies

There can be many advantages of using biomass instead of fossil fuels for power generation, including lower greenhouse gas (GHG) emission, energy cost saving, improved security of supply and demand, waste management/reduction opportunities and local economic development opportunities. However, whether these benefits are realized, and to what extent, depends critically of the sources and the nature of the biomass feedstock.

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Thermo- chemical conversion processes of biomass feedstock

Thermo-chemical process

Combustion process: the cycle used is the conventional rankine cycle with biomass being burned (oxidised) in a high pressure boiler to generate steam. The net power cycle efficiencies that can be achieved are about 23% to 25%. The exhaust of the steam turbine can either be fully condensed to produce power or used partly or fully for another useful heating activity. In addition to exclusive use of biomass combustion to power a steam turbine, biomass can be co-fired with coal in a coal power plant. (EPRI., 2012)

Direct co-firing is the process of adding a percentage of biomass to the fuel mix in a coal- fired power plant. It can be co-fired up to 5-10% of biomass (in energy terms) and 50-80% with extensive pre-treatment of feedstock (i.e. torrefaction) with only minor changes in the handing equipment. For percentages about 10% or if biomass and coal are being separately in different boilers, known as parallel co-firing, the changes in mills, burners and dryers are needed, EPRI.,2012.

Gasification process: is achieved by the partial combustion of the biomass in a low oxygen environment, leading to the release of gaseous product (producer gas or syngas). So- called “allothermal” or indirect gasification is also possible. The gasifier can either be of a “fixed bed”, “fluidized bed” or “entrained flow” configuration. The resulting gas is a mixture of carbon monoxide, water, CO2, char, tar and hydrogen, and it can be used in combustion turbines, micro- turbines, fuel cells or gas turbines. When used in turbines and fuel cells, higher electrical efficiencies can be achieved than those achieved in a steam turbine. It is possible to co-fire a

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power plant either directly (i.e Biomass and coal are gasified together) or indirectly (i.e gasifying coal and biomass separately for use in gas turbines), EPRI. 2012.

Pyrolsis process: pyrolsis is a subset of gasification systems. In pyrolsis, the partial combustion is stopped at a lower temperature (450°c to 600°c) resulting in the creation of liquid bio-oil, as well as gaseous and solid products. The pyrolsis oil can then be used as fuel to generate electricity, EPRI, 2012.

3.3: How Briquetting Work.

There are two approaches to briquetting; both require the loose biomass to be ground to a coarse powder like sawdust.

High Pressure Briquetting: high pressure briquetting uses a power-driven press to raise the pressure of dry powdered biomass to about 1500 bar (150 Mpa). According to D. Fulford et al (2014)This compression heats the biomass to a temperature of about 120°C, which melts the lignin in the woody biomass material. The press forces the hot material through a die at a controlled rate, as the pressure decrease, the lignin cools down and re-solidifies the briquette and then binding the biomass powder into uniform, solid briquettes. This high pressure machines are produced in a wide range of sizes, for example a range capable of processing 30kg/hour to 2000kg/hour. Piston press, screw press and roller press are examples of high pressure briquetting machines.

Low Pressure Briquetting: can be used for materials with low amount of lignin, such as paper and charcoal dust. In this process, the powdered biomass is mixed with water to form a paste and then binder with starch or clay material. A briquetting press is used to push the paste into a mould or through an extruder, or it can simply by shaped by hand, the briquettes thus

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produced are left to dry, so that the binder sets and holds the biomass powder together. Low pressure briquetting machines are often hand operated, using a level that drives a piston to compress the paste. According to D. Fulford et al (2014)

3.4: Biomass Briquetting Technologies

The utilization of agricultural and forestry residues is usually cumber sum due to uneven and troublesome of their characteristics. But these have been overcome by means of densification, i.e. through compaction of the residues into products of high density and well define regular shape. Densification of biomass can be categorized into two main types: briquettes and pellets. Briquettes are of relatively large size (typically 5-6 cm in diameter and 30-40 cm in length) while pellets are small in size (about 1 cm in diameter and 2-4 cm in length), S.C.

Bhattacharya, 2008.

Biomass densification represents a set of technologies for the conversion of biomass residues into a convenient fuel. The technology is also known as briquetting or agglomeration. Depending on the types of equipment used, it could be categorized into five main types: Maninder et al;

2012.

1. Piston press densification 2. Screw press densification 3. Roll press densification 4. Pelletizing

5. Low pressure or manual presses.

Piston press densification: there are two types of piston press (1) the die and punch technology; and (2) hydraulic press. In the die and punch technology, which is also known as ram and die technology, biomass is punched into a die by a reciprocating ram with a very high pressure thereby compressing the mass to obtain a compacted product. The standard size of the

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briquette produced using this machine is 60 mm, diameter. The power required by a machine of capacity 700kg/hr is 25 kW. The hydraulic press process consist of first compacting the biomass in the vertical direction and then again in the horizontal direction. The standard briquette weight is 5 kg and its dimensions are: 450 mm x 160 mm x 80 mm. the power required is 37 kW for 1800 kg/h of briquetting. The technology can accept raw material with moisture content up to 22%. The process of oil hydraulics allows a speed of 7 cycles/minute (cpm) against 270 cpm for the die and punch process. The slowness of operation helps to reduce the wear rate of the parts.

The ram moves approximately 270 times per minute in this process.

Screw press: the compaction ratio of screw presses ranges from 2.5:1 to 6:1 or even more. In this process, the biomass is extruded continuously by one or more screws through a taper die which is heated externally to reduce the friction. Here also, due to the application of high pressures, the temperature rises fluidizing the lignin present in the biomass which acts as a binder.

The outer surface of the briquettes obtained through this process is carbonized and has a hole in the centre which promotes better combustion. Standard size of the briquette is 60 mm diameter.

Roller press: in a briquetting roller press, the feedstock falls in between two rollers, rotating in opposite directions and is compacted into pillow-shaped briquettes. Briquetting biomass usually requires a binder. This type of machine is used for briquetting carbonized biomass to produce charcoal briquettes.

Pelletizing: pelletizing is closely related to briquetting excepted that it uses smaller dies (approximately 30 mm) so that the smaller products are called pellets. The pelletizer has a number of die arranged as holes bored on a thick steel disk or ring and the material is forced into the dies by means of two or three rollers. The two main types of pellet presses are: flat/disk and

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ring types. Other types of pelletizing machines include the punch press and the cog-wheel pelletizer. Pelletizers produce cylindrical briquettes between 5 mm and 3 mm in diameter and of variable length. They have good mechanical strength and combustion characteristics. Pellets are suitable as a fuel for industrial applications where automatic feeding is required. Typically pelletizers can produce up to 1000 kg of pellets per hour but initially require high capital investment and have high energy input requirements.

Manual press and low pressure briquetting: there are different types of manual presses used for briquetting biomass feed stocks. They are specifically designed for the purpose or adapted from existing implements used for other purposes. Manual clay brick making presses are a good example. They are used both for raw biomass feedstock or charcoal. The main advantages of low-pressure briquetting are low capital costs, low operating costs and low levels of skill required to operate the technology. Low-pressure techniques are particularly suitable for briquetting green plant waste such as coir or bagasse (sugar-cane residue). The wet material is shaped under low pressure in simple block presses or extrusion presses. The resulting briquette has a higher density than the original material but still requires drying before it can be used. The dried briquette has little mechanical strength and crumbles easily. The use of a binder is imperative.

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Below is the portrait of different briquetting machines that are used for biomass densification.

Figure: 3.1: roller, screw press, piston press, pelletising machine

Sources: www.alibaba.com Ashen foundation http://www.ashen.org/briquettes

Figure: 3.2: manual press

Sources: Legacy foundation and engineers without borders

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The picture below shows the different briquette types produce from different technologies.

Figure3.3: shows the products of different machines.

Source: www. Google.com.

3.5: Economic analysis of briquetting technologies

Table 3.1, highlight high compaction technology or binderless technology consist of piston and screw press and are becoming more important commercially. In the screw extruder press, the biomass is extruded continuously by a screw through a heated taper die. In the piston press the wear of the contacts parts e.g, the ram and die is less compared to the wear of the screw and die in screw extruder press. The power consumption in the former is less than that of the latter. The briquette quality and production procedure screw press is definitely superior to the piston press. The piston presses are two type, the mechanical and hydraulic press. The mechanical are typically large scale installation 200kg/h to 1800kg/h and hydraulic presses are 50kg/h to 200kg/h and 400kg/h to 1500kg/h. the screw presses are usually available with capacity from 75kg/h to 250kg/h.

Screw press Piston press Pellets

Roller press Manual or low pressure

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Table 3.1: Economic comparison between piston press and screw press technology Piston press Screw press Optimum moisture content of raw

material

10-15% 8-9%

Wear of contact parts Low in case of ram and die High in case of screw

Output from the machine In strokes continuous

Power consumption 50 kWh/ton 60 kWh/ton

Density of briquette 1-1.2gm/cm 1-1.4gm/cm

Maintenance high Low

Combustion performance of briquettes

Not so good Very good

Carbonization of charcoal Not possible Make good charcoal

Suitability in gasifiers Not suitable Suitable

homogeneity Non-homogeneous homogeneous

Capacity 150-2000kg per/hr 75-250kg per/hr

Capital cost Us$ 20-30,000 Us$ 1,350

Sources: FAO, 1996 and EEP, 2013

3.6: Densification technologies in different countries.

Two common types of briquetting presses employed in developing countries are heated- die screw press and piston press. It appears that heated-die screw press technology was invented in Japan in mid-1940s. the technology has spread to most of its neighbouring and nearby countries, particularly Korea, China, Taiwan, Vietnam, Thailand, Malaysia, Philippines, Bangladesh, etc. where heated-die screw-press briquetting machines are used almost exclusively.

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Also, the design of screw-press briquetting machines appears to have evolved and been adapted to suit local conditions in different countries.

The piston press technology is the dominant technology in India, Brazil, and Africa.

While these are locally made in India and Brazil, the African machine appears to be mostly imported. Compared to piston-press machines, heated-die screw press machines have smaller capacity but produce stronger and denser briquettes. Screw press technology is therefore more suitable if the briquettes are to be carbonized to obtain briquetted charcoal.

Besides, conventional binder less briquetting, low-pressure cold briquetting using binder has also been tried in some places. Most worthy among these is the carbonization-briquetting process; in which biomass is first carbonized and the resulting charcoal is briquetted using a suitable binder. The process has been tried for cotton stalks in Sudan and coffee husks in Kenya;

limited use of this technique has been reported in India and Nepal. Briquetting of bagasse using molasses as binder has been reported to have had limited success in Sudan.

Another low-pressure binderless briquetting process involves mixing pulverized chopped and decomposed biomass with water into a pulp. The pulp is pressed inside a perforated pipe to get 4-inch diameter cakes, which are sun-dried to get briquettes, Stanley, 2002. The basic press is made on site and the product is normally of lower density compared with conventional briquettes.

A non-profit organization, Legacy Foundation, is currently involved in dissemination of the technology.

Briquette made from a mixture of pulverized coal, biomass and slaked lime has been introduced by a Japanese company in two Asian countries, China and Indonesia. The briquettes, called coal-biomass briquettes are produced by using a roll-press. It is claimed that the use of the

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desulfurizing agent (slaked lime) and biomass results in cleaner combustion of the briquettes in stove and less of ash compared with coal or coal briquettes Kobayashi, 2002.

Densification technology employed in developed countries, capacity of these plants is much larger, being in the range 1-30 tons per hour.

3.7: Biomass briquetting processes.

There are two main types of briquettes carbonized and non-carbonized, produced by the application of two different processing techniques. Carbonized briquettes are made from biomass sources that have been processed through partial pyrolsis (which drives off volatile compound and moistures leaving a higher concentration of carbon per unit). Hereafter, they are mixed with binders, cast into appropriate shapes through pressing and finally dried. Un-carbonized briquettes are processed directly from biomass sources through various casting and pressing processes, which is known as solidification, EEP, 2013. Depending upon the type of biomass, three processes are generally required involving the following steps. FAO, 1996.

1. Sieving – Drying – Preheating – Densification – Cooling – Packing.

2. Sieving – Crushing – Preheating – Densification – Cooling – Packing.

3. Drying – Crushing – Preheating – Densification – Cooling – Packing.

Step 1, is used for saw dust, Step 2, is used for agro and mill residues which are normally dry.

Eg coffee husk, rice husk, groundnut shell etc. and Step 3, is used for materials like bagasse, mustard, coir path and other cereal stalks.

Converting residues into a densified form has the following advantages

1. The process increase the net calorific value per unit volume

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3. The process helps to solve the problem of residue disposal 4. The fuel produced is uniform in size, shape and quality.

3.8: Pretreatment Technologies to Improve Quality Attributes.

Pretreatment improved both the physical and chemical properties, thereby making the material easy to densify and transport.

1. Grinding: biomass is ground to a certain particle size. This grinding partially breaks down the lignin, increases the specific area of the materials, and contributes to better binding, Peleg, 1977.

2. Preheating: is widely used as it results in a higher quality product. Most briquette producers use preheating to form more stable and dense pellets or briquettes, Bhattacharya, 1993.

3. Stream conditioning and Explosion: an efficient method of pretreatment for both herbaceous and woody biomass, either for densification or ethanol production. The compressed hot water or steam is commonly used in this process. During steam explosion, which is a high-temperature, short-time process, the material is introduced into a rector and heated under pressure at elevated temperatures. This process produces significant physical, chemical, and structural changes in the biomass and makes more lignin sites available for binding during pelletization, Lin and Wyman, 2005.

4. Torrefaction: a method of changing the properties of biomass materials by slowly heating it in an inter-environment to a maximum temperature of 300 degree, Felfli et al.

1998. The process is also called mild pyrolysis as most of the smoke-producing

甘比亞生質燃料棒生產潛力之研究

碩士論文

Graduate Institute of Agricultural Economics College of Bio-Resources and Agriculture

National Taiwan University Master Thesis

甘比亞生質燃料棒生產潛力之研究

A study of biomass briquettes potential in the Gambia.

Ibrahim Colley 柯里 指導教授 : 徐世勳

指導教授:蘇忠楨

Advisor: Dr. Shih-Hsun Hsu, National Taiwan University Co Advisor: Dr. Jung-Jeng Su , National Taiwan University

中華民國 103 年 6 月

June 2014

Table of contents

CHAPTER 1: INTRODUCTION

CHAPTER 2: BACKGROUND OVERVIEW OF THE ECONOMICS AND BUSINESS OF BIOMASS BRIQUETTE PRODUCTION AND

CONSUMPTION

CHAPTER 3: Biomass Briquette Technology and Uses in Different Countries.

Ibrahim Colley 柯里指導教授 : 徐世勳