Environmental Engineering Reference
In-Depth Information
f. Nutrient availability and fertilization regime
g. Pesticide dosing regime
h. Location (including distance from polluting sites as cities, highways, etc.)
3. Age, harvesting season, harvesting collection technology, pickup of extraneous
material (e.g., dust, dirt, soil), transport, handling, and storage
4. Blending strategies
In the following sections, more details concerning the molecular structure and minor
composing elements are dealt with. Biomass in general is composed of mainly organic
matter but in conjunction with a smaller fraction of inorganic compounds containing a
variety of intimately associated phases or minerals with different origins. These have
formed by natural processes, both authigenic (formed in biomass) and detrital (formed
outside biomass but fixed in/on biomass), as well as by anthropogenic (formed in or
outside biomass and fixed in/on biomass) processes. In this respect, one can discrimi-
nate between presyngenesis, syngenesis, epigenesis, and postepigenesis (see Figure 2.2).
The phase composition can be summarized as follows (Vassilev et al., 2010):
1. Organic matter
a. Solid, noncrystalline
—
structural constituents, e.g., (hemi)cellulose, lignin,
and extractives
b. Solid, crystalline
—
organic (combined with inorganic) minerals such as
Ca
-
Mg
-
K
-
Na oxalates
Syngenetic:
during plant growth
Formation by biogenic processes of
growing plants
(
e.g., photosynthesis
)
Authigenic
Epigenetic
Formation after plant death
Natural
Pre-existing, inely dispersed
mineral grains (<1 μm) introduced
in plant by water suspensions
during syngenesis (endocytose)
Presyngenetic
Detrital
Pre-existing, ine-grained particles
(10-100 μm) introduced by water
and wind on plant surfaces, ixed
in pores, voids and cracks
Biomass
Presyngenetic
Syngenetic
Epigenetic
Natural and/or industrial
components (e.g., dust) introduced
during collection, handling,
transport, and further processing
Anthropo-
genic
Techno-
genic
Postsyngenetic
Process
Place
Time
Mechanism
FIGURE 2.2
Origin of phases in biomass, classified based on process, place, time, and
mechanism of formation (based on the table presented by Vassilev et al., 2010).
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