Renewable Energy in Industrial Applications – an ... - Unido

BIOMASS
Biomass gasifiers for kilns and furnaces
In India, the use of gasifiers for thermal
applications in SMEs offers favourable economic
and financial outcomes across a wide range of
different unit capacities and for different
feedstocks such as rice husk and other
agricultural residues. Where gasifiers replace
liquid-fuel use, small (~30 kW) or medium (~100
kW) sized gasifiers have payback periods of the
order of only 6 months, assuming a biomass
supply price of less than 2 USD/GJ (USD 27/t
biomass) (Table 2). However biomass
gasification is still in a stage of variation and
there has been no dominant design yet (Kirkels
and Verbong, 2010). In most markets it is unable
to compete with other technologies, and
technology standardization is needed to ensure
proper operation.
C. BIOMASS AS PETROCHEMICAL
FEEDSTOCK
Carbon is also needed for the production of
materials in the petrochemical sector, where it
comprises around 75% of the total feedstock.
Olefins (mainly ethylene, propylene and
butadiene) are typically produced through the
steam cracking of various petrochemical
Table 3
Production capacity for bio-based plastics in 2009
feedstocks such as ethane, liquid petroleum gas,
naphtha and gas oil. Naphtha is the main
feedstock for the production of aromatics such as
benzene, toluene and xylenes through reforming.
The main alternative feedstock to fossil fuels is
likely to be biomass. But waste products, such
as recycled plastics, can also substitute for some
fossil fuel feedstock. Alternatively, organic
materials such as cellulose fibers, coconut fibers,
starch plastics, fibre boards and paper foams can
be produced which can directly substitute for
petrochemical products in end use applications,
as described in Annex 3. It is also possible to
produce textile materials (mainly viscose and
acetate) from wood pulp and as by-products
from cotton processing.
The production of ethylene from bioethanol is
technically relatively straightforward and some
companies are already doing it on a large scale.
For example, Braskem is currently producing
200 000 t of bio ethylene from sugar cane
ethanol, to be polymerised into high density
polyethylene (HDPE) and linear low density
polyethylene (LLDPE). The current production of
other petrochemical products from bio feedstocks
is set out in Table 3.
[kt/yr]
Cellulose plastics (of which at least 1/3 fully bio-based) 4 000
Partially bio-based thermosets 1 000
Partially bio-based starch plastics 323
Polylactic acid (PLA) 229
Ethylene from bio-based ethanol 200
Polyhydroxyalkanoates (PHA) 80
PUR from bio-based polyol 13
Partially bio-based PTT 10
Bio-based monomers 10
Bio-based Polyamide (PA) 5
Total 5 870
* fully bio-based unless otherwise stated Source: Shen et al, 2009
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