2011 International Conference on Alternative Energy in Developing Countries and Emerging Economies
- 100 -
Punjab is the most advanced state of India, where
thermal and hydel are only two conventional sources
for power generation. During 2009-10 the gross
power generation from hydro electric power plants
was 2559MUs and from thermal power plants was
8994.369MUs
respectively [10]. As at present the
state does not have any major hydro potential, so
thermal generation is mainly concerned. Punjab is
geographically located far away from the coal mines.
While exploring other sources of energy, it was
noticed that some falls were available on canals in
Punjab, where mini hydro plants can be constructed.
Further the state has million hectares of well-irrigated
& fertile land, which produces million ton of crop
residues. It was felt that agro residue (biomass) based
power can provide specific advantages to Punjab and
it is the beginning era for setting up biomass based
power generation units in Punjab. Table 1 shows the
non-conventional energy projects commissioned and
under execution in Punjab.
TABLE
I
N
ON CONVENTIONAL ENERGY PROJECTS IN PUNJAB
Source:MNES
B. Data Collection
Punjab Energy development agency has conducted
a survey in 36 tehsils of Punjab [5] to assess the total
biomass availability, nature of available biomass,
potential of power production and proposed location
and rating of biomass based power plant in that
tehsil. The same is used herewith in the present study.
Overall it is estimated that Punjab state has potential
of 1500MW to generate from agro residue [4]. To
harness this potential some of the plants have already
being sanctioned and some are being sanctioned. The
energy content of one tone of crop residue is nearly
equal to the heat energy content of 0.55 tones of air
dry fuel wood [11]. Sixty one percent of crop residue
in country is produced from straws, remaining 39%
includes sugarcane 23% stalks 11% husk and cobs
are 5% [12]. The samples selected for the present
study covers almost all the agro residues in the state.
The present pattern of disposal of biomass has also
been shown as Figure 1.
Fig. 1. Biomass utilization scenario in Punjab state (India).
C. Data Analysis
Samples of above mentioned agro residue have
been collected across the state and names are
mentioned as per Table 2. The proximate and
ultimate analysis of the collected samples has been
conducted at fuel testing laboratory of National
Fertilizers limited, Bathinda.
D. Thermo Chemical Conversion Process
Thermo-chemical conversion process is the
biomass conversion process at elevated temperature
under varied atmospheric conditions [13] and can be
represented as per chemical reaction no. 2
CH
x
O
y
+n (0.21 O
2
+0.79 N
2
) heat
CO+H
2
+CO
2
+H
2
O+C
x
H
y
+Chars+Tars+Heat (2)
The product formation in the above reaction
depends upon the quantity of air used. It is very
important to define the equivalence ratio (ER) to
understand the reaction mechanism. The equivalence
ratio is the ratio of actual air used in the reaction to
the stoichiometric air required. In the above reaction
if the ER is zero i.e. the reaction takes place in the
absence of air with some external heat supply, the
end products are solid fuel (char) and liquid fuel (tar)
and gases. The process is called pyrolysis. If ER is
greater than and equal to one, the process is called
combustion and the end product is flue gas at high
temperature and sensible heat of flue gas is useful
end product. and if ER varies between zero and less
than one, the process is called gasification. The end
product is gaseous fuel called producer gas. The
process is performed in the reactor called as gasifier.
Various conversion process and schematic power
production from residue are shown as Figure 2.
