2011 International Conference on Alternative Energy in Developing Countries and Emerging Economies
- 55 -
Fig. 4. Elemental sulfur(yellowish particles)
accumulation on the biofiltrated media
C. Methane content
CH
4
isan energy gas containing in biogas which should
be above50-60 percent for general uses and substitutable
for conventional LPG.Our results showed that the outlet
CH
4
increased by 4.4 percent (CH
4
82.3±2.1 percent)
from the inlet biogas at 77.9±2.1 percent at the highest
efficiency of H
2
S removal (96.8 percent). O
2
supplied by
liquid recirculationdid not dilute the CH
4
concentration.
IV. C
ONCLUSIONS
H
2
S
was
effectively
removed
by
acidic
biofiltrationunder a range of pH 4 to 0.5. Longer EBRT
could improve the efficiency of H
2
S removal and sulfuric
acid productions. The liquid recirculation rate at 4.7
m
3
/m
2
/hgave the highest H
2
S removalefficiency, whereas
the sulfuric acid production efficiency favored
highaerated-liquid recirculation rate. The outlet H
2
Swas
lower 500 ppm withthe highest efficiency of H
2
S removal
of96.8 percent, andsulfuric acid production of 0.26
gH
2
SO
4
-S/gH
2
S-S.Thus, acidic
biofiltrationhas a
potential for the biogascleanup for concentrated latex
industry.
A
CKNOWLEDGMENT
This work was financially supported by Prince of
Songkla University Graduate Studies Grant and annual
research budget of Prince of Songkla University contract
no. ENG530040S, Thailand.The authors would like to
thank Chalong Latex Industry Co., Ltd., Songkhla,
Thailand for research facilities and the biogas.
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