biomass sources, characteristics , classification [compatibility mode]

Dr. S. Suresh lecture note at the MANIT

Bhopal on “Bioenergy Engineering"

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BIOMASS SOURCES, CHARACTERISTICS

AND CLASSIFICATION

Dr. S. Suresh

Assistant Professor,

Department of Chemical Engineering, MANIT, Bhopal-

462 007, MP, India

Email: [email protected]



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�Biomass encompasses among others, vegetation, energy crops, as well as biosolids, animal, forestry

and agricultural residues, the organic fraction of municipal waste and certain types of industrial wastes.

�Its appeal is due to its potential worldwide availability, its conversion efficiency and its ability to be

produced and consumed on a CO2-neutral basis.

�The production of second-generation biofuels obtained by waste biomass is actively supported

globally to avoid the direct and side effects that stem from the energetic utilization of energy crops

(OECD/FAO, 2007), and further support effectively waste management policies.

�Waste-to-energy plants offer both generation of clean electric power and environmentally safe waste

management and disposal.

�Many research efforts document the current and potential role of biomass in the future global energy

supply (Yamamoto et al., 2001; Parikka, 2004; Suresh et al., 2011). Theoretically, the total bio-energy

contribution (combined in descending order of theoretical potential by agricultural, forest, animal

residues and organic wastes) could be as high as 1100 EJ, exceeding the current global energy use of 410

EJ (Hoogwijk et al., 2003). Berndes et al. (2003) further reinforce this potential of biomass in the future

global energy supply by analysing and synthesizing earlier studies on the subject. However, a careful

analysis of all the related literature reveals that there is no consensus regarding the biomass potential

among the researchers, but rather their assessments differ strongly.

�One of the most critical bottlenecks in increased biomass utilization for energy production is the cost

of its logistics operations. The rising demand for biomass and the increased complexity of the often

multi-level involved supply systems outline the need for comprehensive waste biomass supply chain

management approaches.

�The requirements with respect to biomass supply in terms of quality and quantity can differ

substantially depending on the energy demand trends, the energy production technology, the end-use of

the power generated and, the cost-efficiency and complexity of its logistics operations.

Dr. S. Suresh lecture note at the MANIT Bhopal on "Bioenergy Engineering"



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Waste biomass supply chains (WBSCs) for energy production are comprised in general of

four general system components: (i) biomass harvesting/collection (from single or several

locations) and pre-treatment, (ii) storage (in one or more intermediate locations), (iii)

transport (using a single or multiple echelons) and (iv) energy conversion (Fig. 1).

WBSCs possess several distinctive characteristics that differentiate them from traditional

supply chains. Firstly, agricultural biomass types are usually characterized by seasonal

availability, thus dictating the need of storing large amounts of biomass for lengthy time

periods, which in turn leads to high inventory holding costs during the year-round operation

of a power plant. Moreover, weather related variability and competing uses of waste biomass

in a dynamically changing market have to be considered when determining the flows of the

material supply network.

The complexity of biomass supply chains is even higher for perishable products, as

perishability constrains severely both the acceptable transportation lead times and the length

of storage time. Furthermore, most forms of biomass tend to have a relatively low energy

density per unit of mass compared with fossil fuels. This often makes handling, storage and

transportation more costly per unit of energy carried. In addition, WBSCs need to be robust

and flexible enough to adapt to unpredictable changes in market conditions, as the demand of

the produced energy depends on the type of the conversion facility and/or the price of

competitive fuel substitutes.




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Fig. 1. Graphical representation of a waste biomass supply chain




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BIOMASS ENERGY PRODUCTION TECHNOLOGIES

A thorough understanding of the technologies available for biomass energy production is a critical input

to the strategic design of any biomass supply chain network. Conversion of waste biomass and organic

substrates into energy encompasses a wide range of different types and sources of biomass, conversion

options, enduse applications and infrastructure requirements (Karagiannidis et al., 2009). Many of the

processes are suitable for either the direct conversion of biomass or the conversion of intermediate types

of biomass. Factors that influence the choice of a conversion process include the type and quantity of

biomass feedstock and the desired form of the produced energy, i.e. end-use requirements,

environmental standards, economic conditions and other project-specific factors (Hulteberg and

Karlsson, 2009).

Biomass can be converted into useful products or exploitable energy via three main process categories

(Fig. 2): (a) thermochemical, (b) bio-chemical and (c) physicochemical processes.

Thermochemical conversion processes convert biomass into a solid, liquid or gaseous fuel (e.g.

gasification, pyrolysis and charcoal production), (Balat et al., 2009). Bio-chemical conversion is based

on biological processes. The most significant options are: alcohol production from biomass containing

sugar, starch and/or celluloses, and biogas production from crops or organic waste material (e.g. animal

manure). Finally, physicochemical conversion processes provide liquid fuels (e.g. biodiesel) through

physical (e.g. pressing) and chemical (e.g. transesterification) processing of dedicated energy crops. In

this context, Fig 2 presents the alternative biomass feedstock and the energy carrier for the presented

conversion technologies.

It is important to obtain a strategic view about the ramifications and various parameters of all these

technological options on waste biomass supply chains; this would facilitate the identification of optimal

configurations for bio-energy supply systems, networks, and of other meaningful improvement options

(Wonglimpiyarat, 2010).




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Fig. 2. Overview of renewable energy production from organic substrates (Iakovou et al. 2004; Suresh et al., 2011)




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SUMMARY AND CONCLUSION

�Logistics and supply chain management are areas of critical importance

for the successful energetic utilization of waste biomass.

�Stakeholders involved in both the design and the execution of such

WBSCs need to address systemically an array of decisions spanning all

levels of the natural hierarchical decision-making process.

�For example, generic system components along with the unique

characteristics of waste biomass supply chains (WBSCs) that differentiate

them from traditional supply chains.

�The natural hierarchy of the decision-making process for the design and

planning of WBSCs based on industrial practice and needs and existing

research.

�Then, we provided a taxonomy of all related research efforts as these are

mapped on the levels of the hierarchy.

Here, identifying gaps in the existing research and thus opportunities for

additional research.




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biomass sources, characteristics , classification [compatibility mode]

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